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-rw-r--r--serve/deliver.c716
-rw-r--r--serve/deliver.h60
-rw-r--r--serve/message-json.c281
-rw-r--r--serve/message-json.h26
-rw-r--r--serve/serve.c1820
5 files changed, 2903 insertions, 0 deletions
diff --git a/serve/deliver.c b/serve/deliver.c
new file mode 100644
index 0000000..0d3da64
--- /dev/null
+++ b/serve/deliver.c
@@ -0,0 +1,716 @@
+#define _POSIX_C_SOURCE 200809L
+#include "deliver.h"
+#include "message-json.h"
+#include "module-text.h"
+#include <errno.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <openssl/ssl.h>
+#include <openssl/x509v3.h>
+#include <arpa/inet.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+
+enum { TIMEOUT_S = 10, FIRST_PAUSE_MS = 100, LONGEST_PAUSE_MS = 10000, GROUPS = PURE_MODULE_NAME / 2, BATCH_MOST = 256,
+ ANSWER_MOST = 1 << 20 };
+enum { DELIVERED, AGAIN, REFUSED_BY_PEER, TLS_FAILED, ANSWER_UNREAD };
+
+typedef struct { char *body; size_t size; uint64_t seq; unsigned char *sent; size_t sent_size; } Pending;
+/* An answer made into its input's message: a table of the fields' starts and
+ * sizes (u32le), then the payload from its prefix on. */
+typedef struct { uint64_t seq; unsigned char *bytes; size_t size, table; } Answer;
+
+struct PureWire {
+ const PureModule *module;
+ uint32_t output;
+ char host[256], port[8], path[1024], source[PURE_SOURCE + 1];
+ pthread_mutex_t lock;
+ pthread_cond_t changed;
+ Pending *queue; /* the sends to deliver, in order, from head */
+ size_t head, count, capacity;
+ uint64_t queued, delivered, attempts, deliveries;
+ unsigned batch; /* how many a request may carry, as the receiver said (X-Pure-Batch); 0: one */
+ bool stopping, started, stuck;
+ pthread_t thread;
+ void (*notify)(void *);
+ void *context;
+ int fd; /* the connection kept for the next send, or -1; changed under the lock */
+ bool tls; /* https: the connection is TLS */
+ SSL *ssl; /* its TLS session */
+ int answer_input; /* the input answers become events of, or -1 */
+ Answer *answers; /* made, for the owner to take in order */
+ size_t answer_head, answer_count, answer_capacity;
+ Answer taken; /* the one the owner took last, kept until it takes the next */
+ uint32_t placed[2 * PURE_MODULE_FIELDS];
+};
+
+/* ---- TLS: one client context, verifying the receiver's certificate against
+ * the system's CAs or the file pure_wire_trust named, and its name. */
+static pthread_once_t tls_once = PTHREAD_ONCE_INIT;
+static SSL_CTX *tls_context;
+static const char *tls_ca;
+
+void pure_wire_trust(const char *ca_file) { tls_ca = ca_file; }
+
+static void make_tls_context(void) {
+ SSL_CTX *context = SSL_CTX_new(TLS_client_method());
+ if (!context) return;
+ if (!SSL_CTX_set_min_proto_version(context, TLS1_2_VERSION) ||
+ !(tls_ca ? SSL_CTX_load_verify_locations(context, tls_ca, NULL) : SSL_CTX_set_default_verify_paths(context))) {
+ SSL_CTX_free(context);
+ return;
+ }
+ SSL_CTX_set_verify(context, SSL_VERIFY_PEER, NULL);
+ SSL_CTX_set_mode(context, SSL_MODE_AUTO_RETRY);
+ tls_context = context;
+}
+
+/* ---- A send as JSON: its fields in order, a group's fields as an object. */
+
+typedef struct { char *bytes; size_t size, capacity; bool failed; } Text;
+
+static void put(Text *t, const void *bytes, size_t size) {
+ if (t->failed) return;
+ if (size > t->capacity - t->size) {
+ size_t capacity = t->capacity ? t->capacity : 256;
+ while (size > capacity - t->size) capacity *= 2;
+ char *grown = realloc(t->bytes, capacity);
+ if (!grown) { t->failed = true; return; }
+ t->bytes = grown;
+ t->capacity = capacity;
+ }
+ memcpy(t->bytes + t->size, bytes, size);
+ t->size += size;
+}
+
+static void put_string(Text *t, const unsigned char *bytes, size_t size) {
+ put(t, "\"", 1);
+ size_t run = 0;
+ for (size_t i = 0; i < size; ++i) {
+ unsigned char b = bytes[i];
+ if (b != '"' && b != '\\' && b >= 0x20) continue;
+ put(t, bytes + run, i - run);
+ char escaped[8];
+ if (b == '"' || b == '\\') put(t, (char[]){'\\', (char)b}, 2);
+ else put(t, escaped, (size_t)snprintf(escaped, sizeof(escaped), "\\u%04x", b));
+ run = i + 1;
+ }
+ put(t, bytes + run, size - run);
+ put(t, "\"", 1);
+}
+
+static uint32_t read_u32(const unsigned char *p) { return p[0] | p[1] << 8 | (uint32_t)p[2] << 16 | (uint32_t)p[3] << 24; }
+
+/* The group a field is in: the length of its name before the last dot (0: none). */
+static size_t group_of(const char *name) {
+ const char *dot = strrchr(name, '.');
+ return dot ? (size_t)(dot - name) : 0;
+}
+
+/* Whether the group path open (length open_size) holds the group of name (length size). */
+static bool holds(const char *open, size_t open_size, const char *name, size_t size) {
+ return open_size <= size && !memcmp(open, name, open_size) && (open_size == size || !open_size || name[open_size] == '.');
+}
+
+static bool encode(const PureWire *w, PureSpan payload, Text *t) {
+ const PureModule *m = w->module;
+ const PureInputShape *shape = &m->input[w->output];
+ if (payload.size < shape->prefix) return false;
+ char open[PURE_MODULE_NAME] = "";
+ size_t open_size = 0, at = shape->prefix;
+ unsigned depth = 0;
+ bool first[GROUPS + 1] = {true};
+ put(t, "{", 1);
+ for (uint32_t f = 0; f < shape->field_count; ++f) {
+ const PureField *field = &m->field[shape->field_start + f];
+ size_t group = group_of(field->name);
+ while (depth && !holds(open, open_size, field->name, group)) {
+ put(t, "}", 1);
+ --depth;
+ open_size = group_of(open) < open_size ? group_of(open) : 0;
+ open[open_size] = 0;
+ }
+ while (open_size < group) {
+ size_t start = open_size ? open_size + 1 : 0, end = start;
+ while (end < group && field->name[end] != '.') ++end;
+ if (!first[depth]) put(t, ",", 1);
+ first[depth] = false;
+ put_string(t, (const unsigned char *)field->name + start, end - start);
+ put(t, ":{", 2);
+ first[++depth] = true;
+ memcpy(open, field->name, end);
+ open[open_size = end] = 0;
+ }
+ if (!first[depth]) put(t, ",", 1);
+ first[depth] = false;
+ const char *key = field->name + (group ? group + 1 : 0);
+ put_string(t, (const unsigned char *)key, strlen(key));
+ put(t, ":", 1);
+ char digits[32];
+ if (field->type == PURE_FIELD_U32) {
+ put(t, digits, (size_t)snprintf(digits, sizeof(digits), "%u", (unsigned)read_u32(payload.data + field->offset)));
+ } else if (field->type == PURE_FIELD_NUMBER) {
+ uint64_t bits = read_u32(payload.data + field->offset) | (uint64_t)read_u32(payload.data + field->offset + 4) << 32;
+ double value;
+ memcpy(&value, &bits, sizeof(value));
+ put(t, digits, pure_format_number(value, digits));
+ } else {
+ size_t size = field->offset == PURE_FIELD_REST ? payload.size - at : read_u32(payload.data + field->offset);
+ if (size > payload.size - at) return false;
+ PureSpan value = {payload.data + at, size};
+ if (!pure_utf8_valid(value)) return false; /* bytes that are not text have no JSON form */
+ put_string(t, value.data, size);
+ at += size;
+ }
+ }
+ while (depth--) put(t, "}", 1);
+ put(t, "}", 1);
+ return !t->failed;
+}
+
+/* ---- The wire. */
+
+PureWire *pure_wire_open(const PureModule *m, const char *output, const char *url, const char *source,
+ char *error, size_t size) {
+ int index = pure_module_input(m, output);
+ if (index < 0 || m->input[index].kind != PURE_KIND_OUTPUT) {
+ snprintf(error, size, "no output '%s'", output);
+ return NULL;
+ }
+ /* A group's fields are together, so each group is one object. */
+ const PureInputShape *shape = &m->input[index];
+ for (uint32_t f = 1; f < shape->field_count; ++f) {
+ const char *name = m->field[shape->field_start + f].name;
+ for (uint32_t e = 0; e + 1 < f; ++e) {
+ const char *earlier = m->field[shape->field_start + e].name, *between = m->field[shape->field_start + f - 1].name;
+ size_t shared = 0;
+ while (earlier[shared] && earlier[shared] == name[shared]) ++shared;
+ while (shared && earlier[shared - 1] != '.') --shared; /* the groups both are in */
+ if (shared && strncmp(between, name, shared)) {
+ snprintf(error, size, "the fields of output '%s' in one group are not together", output);
+ return NULL;
+ }
+ }
+ }
+ size_t length = strlen(source);
+ if (!length || length > PURE_SOURCE) {
+ snprintf(error, size, "a source name has 1 to %d bytes", PURE_SOURCE);
+ return NULL;
+ }
+ bool tls = !strncmp(url, "https://", 8);
+ if (!tls && strncmp(url, "http://", 7)) {
+ snprintf(error, size, "a URL is http[s]://host[:port]/path");
+ return NULL;
+ }
+ if (tls) {
+ pthread_once(&tls_once, make_tls_context);
+ if (!tls_context) {
+ snprintf(error, size, "no TLS context: %s cannot be read", tls_ca ? tls_ca : "the system's CAs");
+ return NULL;
+ }
+ }
+ const char *host = url + (tls ? 8 : 7), *slash = strchr(host, '/'), *colon = memchr(host, ':', slash ? (size_t)(slash - host) : strlen(host));
+ const char *host_end = colon ? colon : slash ? slash : host + strlen(host);
+ const char *port = colon ? colon + 1 : tls ? "443" : "80";
+ size_t port_size = colon ? (size_t)((slash ? slash : host + strlen(host)) - port) : strlen(port);
+ if (host_end == host || (size_t)(host_end - host) >= 256 || !port_size || port_size >= 8 ||
+ (slash && strlen(slash) >= 1024)) {
+ snprintf(error, size, "a URL is http://host[:port]/path");
+ return NULL;
+ }
+ PureWire *w = calloc(1, sizeof(*w));
+ if (!w) { snprintf(error, size, "out of memory"); return NULL; }
+ w->module = m;
+ w->output = (uint32_t)index;
+ memcpy(w->host, host, (size_t)(host_end - host));
+ memcpy(w->port, port, port_size);
+ snprintf(w->path, sizeof(w->path), "%s", slash ? slash : "/");
+ memcpy(w->source, source, length + 1);
+ w->fd = -1;
+ w->tls = tls;
+ w->answer_input = -1;
+ pthread_mutex_init(&w->lock, NULL);
+ pthread_cond_init(&w->changed, NULL);
+ return w;
+}
+
+uint32_t pure_wire_output(const PureWire *w) { return w->output; }
+
+bool pure_wire_reply(PureWire *w, uint32_t input, char *error, size_t size) {
+ const PureModule *m = w->module;
+ if (input >= m->inputs || m->input[input].kind != PURE_KIND_MESSAGE || m->input[input].keyed) {
+ snprintf(error, size, "an answer goes to a message input without a key");
+ return false;
+ }
+ w->answer_input = (int)input;
+ return true;
+}
+
+bool pure_wire_answer(PureWire *w, PureWireAnswer *out) {
+ free(w->taken.bytes);
+ w->taken = (Answer){0};
+ pthread_mutex_lock(&w->lock);
+ bool some = w->answer_count > 0;
+ if (some) {
+ w->taken = w->answers[w->answer_head++];
+ --w->answer_count;
+ w->delivered = w->taken.seq; /* trimmed after the owner applies it */
+ }
+ pthread_mutex_unlock(&w->lock);
+ if (!some) return false;
+ const PureInputShape *in = &w->module->input[w->answer_input];
+ for (size_t i = 0; i < 2 * (size_t)in->field_count; ++i) w->placed[i] = read_u32(w->taken.bytes + 4 * i);
+ *out = (PureWireAnswer){(uint32_t)w->answer_input, w->taken.seq,
+ {w->taken.bytes + w->taken.table, w->taken.size - w->taken.table}, w->placed, w->source};
+ return true;
+}
+uint64_t pure_wire_queued(const PureWire *w) { return w->queued; }
+
+uint64_t pure_wire_delivered(PureWire *w) {
+ pthread_mutex_lock(&w->lock);
+ uint64_t delivered = w->delivered;
+ pthread_mutex_unlock(&w->lock);
+ return delivered;
+}
+
+void pure_wire_counts(PureWire *w, uint64_t *delivered, uint64_t *attempts) {
+ pthread_mutex_lock(&w->lock);
+ *delivered = w->deliveries;
+ *attempts = w->attempts;
+ pthread_mutex_unlock(&w->lock);
+}
+
+bool pure_wire_queue(PureWire *w, uint64_t seq, PureSpan payload) {
+ if (w->stuck) return false;
+ Text t = {0};
+ if (!encode(w, payload, &t)) {
+ free(t.bytes);
+ w->stuck = true;
+ fprintf(stderr, "{\"wire\":\"%s\",\"seq\":%llu,\"error\":\"no JSON form: its bytes are not text\"}\n", w->source,
+ (unsigned long long)seq);
+ return false;
+ }
+ pthread_mutex_lock(&w->lock);
+ if (w->head + w->count == w->capacity) {
+ if (w->head) {
+ memmove(w->queue, w->queue + w->head, w->count * sizeof(*w->queue));
+ w->head = 0;
+ } else {
+ size_t capacity = w->capacity ? 2 * w->capacity : 16;
+ Pending *grown = realloc(w->queue, capacity * sizeof(*grown));
+ if (!grown) {
+ pthread_mutex_unlock(&w->lock);
+ free(t.bytes);
+ return false; /* it stays in the outbox: queued after the next save */
+ }
+ w->queue = grown;
+ w->capacity = capacity;
+ }
+ }
+ unsigned char *sent = NULL;
+ if (w->answer_input >= 0 && !(sent = malloc(payload.size ? payload.size : 1))) {
+ pthread_mutex_unlock(&w->lock);
+ free(t.bytes);
+ return false;
+ }
+ if (sent && payload.size) memcpy(sent, payload.data, payload.size);
+ w->queue[w->head + w->count++] = (Pending){t.bytes, t.size, seq, sent, payload.size};
+ w->queued = seq;
+ pthread_cond_signal(&w->changed);
+ pthread_mutex_unlock(&w->lock);
+ return true;
+}
+
+/* ---- HTTP/1.1, one request at a time on a kept connection. */
+
+typedef struct { PureWire *wire; char bytes[4096]; size_t at, end; } Reader;
+
+static bool fill(Reader *r) {
+ if (r->at == r->end) r->at = r->end = 0;
+ if (r->end == sizeof(r->bytes)) return false;
+ PureWire *w = r->wire;
+ ssize_t n;
+ if (w->ssl) n = SSL_read(w->ssl, r->bytes + r->end, (int)(sizeof(r->bytes) - r->end));
+ else do n = recv(w->fd, r->bytes + r->end, sizeof(r->bytes) - r->end, 0); while (n < 0 && errno == EINTR);
+ if (n <= 0) return false;
+#ifdef TCP_QUICKACK
+ /* Acknowledge at once: a server that writes an answer in pieces holds the
+ * next piece until the first is acknowledged (Nagle), which a delayed
+ * acknowledgement would stall for 40 ms. The flag does not stay set. */
+ int one = 1;
+ setsockopt(w->fd, IPPROTO_TCP, TCP_QUICKACK, &one, sizeof(one));
+#endif
+ r->end += (size_t)n;
+ return true;
+}
+
+/* A line without its CRLF, in line (at most size - 1 bytes). */
+static bool read_line(Reader *r, char *line, size_t size) {
+ for (;;) {
+ char *end = memchr(r->bytes + r->at, '\n', r->end - r->at);
+ if (end) {
+ size_t length = (size_t)(end - (r->bytes + r->at));
+ if (length && end[-1] == '\r') --length;
+ if (length >= size) return false;
+ memcpy(line, r->bytes + r->at, length);
+ line[length] = 0;
+ r->at = (size_t)(end - r->bytes) + 1;
+ return true;
+ }
+ if (r->at) {
+ memmove(r->bytes, r->bytes + r->at, r->end - r->at);
+ r->end -= r->at;
+ r->at = 0;
+ }
+ if (!fill(r)) return false;
+ }
+}
+
+/* size bytes of the body: kept in into (up to ANSWER_MOST), or skipped when it is NULL. */
+static bool take(Reader *r, uint64_t size, Text *into) {
+ if (into && size > ANSWER_MOST - into->size) return false;
+ while (size) {
+ if (r->at == r->end && !fill(r)) return false;
+ size_t n = r->end - r->at < size ? r->end - r->at : (size_t)size;
+ if (into) put(into, r->bytes + r->at, n);
+ r->at += n;
+ size -= n;
+ }
+ return !into || !into->failed;
+}
+
+static bool send_all(PureWire *w, const char *bytes, size_t size) {
+ while (size) {
+ ssize_t n = w->ssl ? SSL_write(w->ssl, bytes, (int)(size < INT32_MAX ? size : INT32_MAX)) :
+ send(w->fd, bytes, size, MSG_NOSIGNAL);
+ if (n < 0 && !w->ssl && errno == EINTR) continue;
+ if (n <= 0) return false;
+ bytes += n;
+ size -= (size_t)n;
+ }
+ return true;
+}
+
+/* TLS over a connected socket: the receiver's certificate must name the host
+ * (a DNS name, or an IP address written as one). */
+static SSL *start_tls(const PureWire *w, int fd) {
+ SSL *ssl = SSL_new(tls_context);
+ if (!ssl) return NULL;
+ unsigned char address[16];
+ bool literal = inet_pton(AF_INET, w->host, address) == 1 || inet_pton(AF_INET6, w->host, address) == 1;
+ bool named = literal ? X509_VERIFY_PARAM_set1_ip_asc(SSL_get0_param(ssl), w->host) == 1 :
+ SSL_set_tlsext_host_name(ssl, w->host) == 1 && SSL_set1_host(ssl, w->host) == 1;
+ if (!named || SSL_set_fd(ssl, fd) != 1 || SSL_connect(ssl) != 1 || SSL_get_verify_result(ssl) != X509_V_OK) {
+ SSL_free(ssl);
+ return NULL;
+ }
+ return ssl;
+}
+
+static int connect_to(const PureWire *w) {
+ struct addrinfo hints = {.ai_family = AF_UNSPEC, .ai_socktype = SOCK_STREAM}, *list;
+ if (getaddrinfo(w->host, w->port, &hints, &list)) return -1;
+ int fd = -1;
+ for (struct addrinfo *a = list; a && fd < 0; a = a->ai_next) {
+ fd = socket(a->ai_family, a->ai_socktype | SOCK_CLOEXEC, a->ai_protocol);
+ if (fd < 0) continue;
+ struct timeval limit = {TIMEOUT_S, 0};
+ int one = 1;
+ setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &limit, sizeof(limit));
+ setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &limit, sizeof(limit));
+ setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
+ if (connect(fd, a->ai_addr, a->ai_addrlen)) {
+ close(fd);
+ fd = -1;
+ }
+ }
+ freeaddrinfo(list);
+ return fd;
+}
+
+static void drop_connection(PureWire *w) {
+ pthread_mutex_lock(&w->lock);
+ if (w->ssl) SSL_free(w->ssl);
+ if (w->fd >= 0) close(w->fd);
+ w->ssl = NULL;
+ w->fd = -1;
+ pthread_mutex_unlock(&w->lock);
+}
+
+/* A fault a Pure receiver answers when its app refused the message. */
+static bool refusal(const char *error) {
+ static const char *const faults[] = {"divide", "non_finite", "clamp", "limit", "not_found", "encoding", "exists"};
+ for (size_t i = 0; i < sizeof(faults) / sizeof(*faults); ++i) if (!strcmp(error, faults[i])) return true;
+ return false;
+}
+
+/* The answer to one request: its status, whether a Pure receiver refused it,
+ * and whether the connection may carry the next. */
+static bool read_answer(PureWire *w, int *status, bool *refused, bool *keep, unsigned *batch, Text *body) {
+ Reader r = {.wire = w};
+ char line[1024];
+ if (!read_line(&r, line, sizeof(line)) || strncmp(line, "HTTP/1.", 7) || strlen(line) < 12) return false;
+ *status = atoi(line + 9);
+ *keep = line[7] == '1';
+ *refused = false;
+ uint64_t length = 0;
+ bool sized = false, chunked = false;
+ while (read_line(&r, line, sizeof(line))) {
+ if (!*line) {
+ if (chunked) {
+ for (;;) {
+ uint64_t chunk;
+ if (!read_line(&r, line, sizeof(line))) return false;
+ chunk = strtoull(line, NULL, 16);
+ if (!chunk) break;
+ if (!take(&r, chunk, body) || !read_line(&r, line, sizeof(line))) return false;
+ }
+ while (read_line(&r, line, sizeof(line)) && *line) {}
+ return true;
+ }
+ if (*status == 204 || *status == 304 || *status < 200) return true;
+ if (sized) return take(&r, length, body);
+ *keep = false; /* the body runs to the close */
+ while (fill(&r)) {
+ if (body && !take(&r, r.end - r.at, body)) return false;
+ r.at = r.end;
+ }
+ return true;
+ }
+ char *value = strchr(line, ':');
+ if (!value) return false;
+ *value++ = 0;
+ while (*value == ' ' || *value == '\t') ++value;
+ if (!strcasecmp(line, "Content-Length")) { length = strtoull(value, NULL, 10); sized = true; }
+ else if (!strcasecmp(line, "Transfer-Encoding")) chunked = !strcasecmp(value, "chunked");
+ else if (!strcasecmp(line, "Connection")) *keep = strcasecmp(value, "close") != 0 && *keep;
+ else if (!strcasecmp(line, "X-Pure-Error")) *refused = refusal(value);
+ else if (!strcasecmp(line, "X-Pure-Batch")) *batch = (unsigned)strtoul(value, NULL, 10);
+ }
+ return false;
+}
+
+static void write_u32(unsigned char *p, uint32_t v) { for (unsigned i = 0; i < 4; ++i) p[i] = (unsigned char)(v >> (8 * i)); }
+
+/* The answer (status, body) to the send p as a message of the answer input:
+ * fields from the body's JSON object by name, others skipped; a field the
+ * body lacks from the send's field of that name and type; a u32 field named
+ * http_status from the status. False when a field has none of these. */
+static bool form_answer(const PureWire *w, int status, const Text *body, const Pending *p, Answer *out) {
+ const PureModule *m = w->module;
+ const PureInputShape *in = &m->input[w->answer_input], *sent = &m->input[w->output];
+ size_t table = 8 * (size_t)in->field_count, total = table + in->prefix + body->size + p->sent_size;
+ unsigned char *bytes = calloc(1, total ? total : 1);
+ if (!bytes) return false;
+ unsigned char *prefix = bytes + table, *text = prefix + in->prefix, *copy = text + body->size;
+ if (body->size) memcpy(text, body->bytes, body->size);
+ if (p->sent_size) memcpy(copy, p->sent, p->sent_size);
+ PureJsonMessage message = {.module = m, .shape = in, .payload = prefix, .table = bytes, .lenient = true};
+ size_t at = pure_json_space(text, 0, body->size);
+ if (at < body->size && text[at] == '{' && pure_json_message(&message, text, body->size, &at)) {
+ free(bytes);
+ return false;
+ }
+ for (uint32_t f = 0; f < in->field_count; ++f) {
+ if (message.seen[f]) continue;
+ const PureField *field = &m->field[in->field_start + f];
+ if (field->type == PURE_FIELD_U32 && !strcmp(field->name, "http_status")) {
+ write_u32(prefix + field->offset, (uint32_t)status);
+ continue;
+ }
+ /* The send's field of the same name and type, and where its bytes are. */
+ size_t start = sent->prefix, length = 0;
+ const PureField *from = NULL;
+ for (uint32_t g = 0; g < sent->field_count && !from; ++g) {
+ const PureField *other = &m->field[sent->field_start + g];
+ bool variable = other->type == PURE_FIELD_BYTES || other->type == PURE_FIELD_TEXT;
+ if (variable) length = other->offset == PURE_FIELD_REST ? p->sent_size - start : read_u32(p->sent + other->offset);
+ if (!strcmp(other->name, field->name) && other->type == field->type) from = other;
+ else if (variable) start += length;
+ }
+ bool variable = field->type == PURE_FIELD_BYTES || field->type == PURE_FIELD_TEXT;
+ if (!from || (variable && (start > p->sent_size || length > p->sent_size - start))) {
+ free(bytes);
+ return false;
+ }
+ if (field->type == PURE_FIELD_U32 || field->type == PURE_FIELD_NUMBER)
+ memcpy(prefix + field->offset, p->sent + from->offset, field->type == PURE_FIELD_U32 ? 4 : 8);
+ else {
+ write_u32(bytes + 8 * f, (uint32_t)(copy + start - prefix));
+ write_u32(bytes + 8 * f + 4, (uint32_t)length);
+ }
+ }
+ *out = (Answer){p->seq, bytes, total, table};
+ return true;
+}
+
+/* One request for count sends from p (numbered in a row): one object, or
+ * an array of them for a receiver that takes batches. A final answer to a
+ * send whose answers are wired is made into *answer. */
+static int post(PureWire *w, const Pending *p, unsigned count, Answer *answer) {
+ size_t body = count > 1 ? count + 1 : 0;
+ for (unsigned i = 0; i < count; ++i) body += p[i].size;
+ char head[2048], batch[32] = "";
+ if (count > 1) snprintf(batch, sizeof(batch), "X-Pure-Count: %u\r\n", count);
+ int size = snprintf(head, sizeof(head),
+ "POST %s HTTP/1.1\r\nHost: %s:%s\r\nContent-Type: application/json\r\nContent-Length: %zu\r\n"
+ "X-Pure-Source: %s\r\nX-Pure-Sequence: %llu\r\n%sIdempotency-Key: %s-%llu\r\n\r\n",
+ w->path, w->host, w->port, body, w->source, (unsigned long long)p->seq, batch, w->source,
+ (unsigned long long)p->seq);
+ /* A kept connection the peer closed is tried once more on a new one. */
+ for (int attempt = 0; attempt < 2; ++attempt) {
+ bool fresh = w->fd < 0;
+ if (fresh) {
+ int fd = connect_to(w);
+ if (fd < 0) return AGAIN;
+ pthread_mutex_lock(&w->lock);
+ w->fd = fd;
+ bool stopping = w->stopping;
+ pthread_mutex_unlock(&w->lock);
+ if (stopping) return AGAIN;
+ SSL *ssl = w->tls ? start_tls(w, fd) : NULL;
+ if (w->tls && !ssl) {
+ drop_connection(w);
+ return TLS_FAILED;
+ }
+ pthread_mutex_lock(&w->lock);
+ w->ssl = ssl;
+ pthread_mutex_unlock(&w->lock);
+ }
+ int status;
+ bool refused, keep, sent = send_all(w, head, (size_t)size);
+ unsigned batch_size = 0;
+ Text body = {0};
+ for (unsigned i = 0; sent && i < count; ++i)
+ sent = (!i || count == 1 || send_all(w, ",", 1)) && (i || count == 1 || send_all(w, "[", 1)) &&
+ send_all(w, p[i].body, p[i].size);
+ if (sent && count > 1) sent = send_all(w, "]", 1);
+ if (!sent || !read_answer(w, &status, &refused, &keep, &batch_size, w->answer_input >= 0 ? &body : NULL)) {
+ free(body.bytes);
+ drop_connection(w);
+ if (fresh) return AGAIN;
+ continue;
+ }
+ if (!keep) drop_connection(w);
+ if (batch_size && w->answer_input < 0) w->batch = batch_size;
+ if (status == 408 || status == 429 || status >= 500) {
+ free(body.bytes);
+ return AGAIN;
+ }
+ if (w->answer_input >= 0 && status >= 200 && status < 500) { /* a final answer: the app hears it */
+ bool formed = form_answer(w, status, &body, p, answer);
+ free(body.bytes);
+ return formed ? DELIVERED : ANSWER_UNREAD;
+ }
+ free(body.bytes);
+ if ((status >= 200 && status < 300) || (status >= 400 && status < 500 && refused)) return DELIVERED;
+ return REFUSED_BY_PEER;
+ }
+ return AGAIN;
+}
+
+static void *deliver(void *context) {
+ PureWire *w = context;
+ long pause_ms = 0;
+ uint64_t reported = 0;
+ pthread_mutex_lock(&w->lock);
+ for (;;) {
+ while (!w->stopping && !w->count) pthread_cond_wait(&w->changed, &w->lock);
+ if (w->stopping) break;
+ /* As many as the receiver takes at once; their bodies stay put while
+ * the queue only grows behind them. */
+ unsigned count = w->batch > 1 ? (unsigned)(w->count < w->batch ? w->count : w->batch) : 1;
+ Pending next[BATCH_MOST];
+ if (count > BATCH_MOST) count = BATCH_MOST;
+ memcpy(next, w->queue + w->head, count * sizeof(*next));
+ ++w->attempts;
+ pthread_mutex_unlock(&w->lock);
+ Answer answer = {0};
+ int outcome = post(w, next, count, &answer);
+ pthread_mutex_lock(&w->lock);
+ if (outcome == DELIVERED && answer.bytes) { /* for the owner, who then counts it delivered */
+ if (w->answer_head + w->answer_count == w->answer_capacity) {
+ if (w->answer_head) {
+ memmove(w->answers, w->answers + w->answer_head, w->answer_count * sizeof(*w->answers));
+ w->answer_head = 0;
+ } else {
+ size_t capacity = w->answer_capacity ? 2 * w->answer_capacity : 16;
+ Answer *grown = realloc(w->answers, capacity * sizeof(*grown));
+ if (!grown) { free(answer.bytes); outcome = AGAIN; }
+ else { w->answers = grown; w->answer_capacity = capacity; }
+ }
+ }
+ if (outcome == DELIVERED) w->answers[w->answer_head + w->answer_count++] = answer;
+ }
+ if (outcome == DELIVERED) {
+ for (unsigned i = 0; i < count; ++i) {
+ free(w->queue[w->head + i].body);
+ free(w->queue[w->head + i].sent);
+ }
+ w->head += count;
+ w->count -= count;
+ if (!answer.bytes) w->delivered = next[count - 1].seq;
+ w->deliveries += count;
+ pause_ms = 0;
+ pthread_mutex_unlock(&w->lock);
+ if (w->notify) w->notify(w->context);
+ pthread_mutex_lock(&w->lock);
+ continue;
+ }
+ if (outcome != AGAIN && reported != next[0].seq) {
+ fprintf(stderr, "{\"wire\":\"%s\",\"seq\":%llu,\"error\":\"%s\"}\n", w->source,
+ (unsigned long long)next[0].seq, outcome == TLS_FAILED ? "the receiver's certificate is not trusted; trying again" :
+ outcome == ANSWER_UNREAD ? "its answer does not make the answer input's message; trying again" :
+ "the receiver does not take it; trying again");
+ reported = next[0].seq;
+ }
+ pause_ms = outcome != AGAIN ? LONGEST_PAUSE_MS : pause_ms ? 2 * pause_ms : FIRST_PAUSE_MS;
+ if (pause_ms > LONGEST_PAUSE_MS) pause_ms = LONGEST_PAUSE_MS;
+ struct timespec until;
+ clock_gettime(CLOCK_REALTIME, &until);
+ until.tv_sec += pause_ms / 1000;
+ until.tv_nsec += (pause_ms % 1000) * 1000000;
+ if (until.tv_nsec >= 1000000000) { ++until.tv_sec; until.tv_nsec -= 1000000000; }
+ while (!w->stopping && pthread_cond_timedwait(&w->changed, &w->lock, &until) == 0) {}
+ }
+ pthread_mutex_unlock(&w->lock);
+ return NULL;
+}
+
+bool pure_wire_start(PureWire *w, void (*notify)(void *), void *context) {
+ w->notify = notify;
+ w->context = context;
+ w->started = pthread_create(&w->thread, NULL, deliver, w) == 0;
+ return w->started;
+}
+
+void pure_wire_close(PureWire *w) {
+ if (!w) return;
+ pthread_mutex_lock(&w->lock);
+ w->stopping = true;
+ if (w->fd >= 0) shutdown(w->fd, SHUT_RDWR); /* a send or an answer waited for ends now */
+ pthread_cond_broadcast(&w->changed);
+ pthread_mutex_unlock(&w->lock);
+ if (w->started) pthread_join(w->thread, NULL);
+ if (w->ssl) SSL_free(w->ssl);
+ if (w->fd >= 0) close(w->fd);
+ for (size_t i = 0; i < w->count; ++i) {
+ free(w->queue[w->head + i].body);
+ free(w->queue[w->head + i].sent);
+ }
+ for (size_t i = 0; i < w->answer_count; ++i) free(w->answers[w->answer_head + i].bytes);
+ free(w->answers);
+ free(w->taken.bytes);
+ free(w->queue);
+ pthread_cond_destroy(&w->changed);
+ pthread_mutex_destroy(&w->lock);
+ free(w);
+}
diff --git a/serve/deliver.h b/serve/deliver.h
new file mode 100644
index 0000000..2d1da29
--- /dev/null
+++ b/serve/deliver.h
@@ -0,0 +1,60 @@
+#ifndef PURE_DELIVER_H
+#define PURE_DELIVER_H
+#include "module.h"
+
+/* Delivering an app's saved sends over HTTP (docs/research/083-delivery-over-http.md).
+ * A wire takes one output's sends in order: each goes as a JSON object of
+ * its fields (groups as objects inside) by POST to a URL, with the headers
+ * X-Pure-Source (the sender's name for the output), X-Pure-Sequence and
+ * Idempotency-Key, one at a time, again and again until it is delivered:
+ * a 2xx answer, or a Pure receiver's refusal (a 4xx with X-Pure-Error
+ * naming a fault: it heard the message and refused it). 408, 429, 5xx and
+ * no answer are tried again after a pause (0.1 s doubling to 10 s); another
+ * 4xx is logged and tried again every 10 s. Nothing is ever dropped: what is
+ * not delivered stays in the app's outbox, and a receiver applies a number
+ * once, so a send delivered twice (its answer lost) is harmless. */
+typedef struct PureWire PureWire;
+
+/* A wire for the output named output of m to url (http[s]://host[:port]/path),
+ * as source; NULL with why in error when it cannot be. An https receiver's
+ * certificate must be trusted (the system's CAs, or the file given to
+ * pure_wire_trust before the first https wire) and name its host. */
+void pure_wire_trust(const char *ca_file);
+PureWire *pure_wire_open(const PureModule *m, const char *output, const char *url, const char *source,
+ char *error, size_t size);
+uint32_t pure_wire_output(const PureWire *);
+/* The owner's side: queue a saved send numbered after the last queued one
+ * (it is encoded now); false when it cannot be (a bytes field that is not
+ * UTF-8 has no JSON form), and the wire then stops at it. */
+bool pure_wire_queue(PureWire *, uint64_t seq, PureSpan payload);
+uint64_t pure_wire_queued(const PureWire *);
+/* The last number delivered; any thread. */
+uint64_t pure_wire_delivered(PureWire *);
+/* Deliver on a thread of the wire's own, calling notify after each delivery. */
+bool pure_wire_start(PureWire *, void (*notify)(void *), void *context);
+/* Stop (a delivery under way is finished or abandoned) and free. */
+void pure_wire_close(PureWire *);
+/* Answers as events: the final answer to each send (a 2xx, or a 4xx but 408
+ * and 429) becomes a message event of input (a message without a key), in
+ * the order sent: its fields come from the answer's JSON object by name
+ * (other members are skipped), a field the answer lacks from the send's
+ * field of that name and type (as a request's id), and a u32 field named
+ * http_status is the answer's status. An answer that makes no message is
+ * logged and the send tried again every 10 s. Answers go one per request. */
+bool pure_wire_reply(PureWire *, uint32_t input, char *error, size_t size);
+/* The owner's side: the next answer in order, or false. Taking it counts
+ * its send delivered (the owner applies the answer, then trims); what out
+ * points to is the wire's until the next call. The answer is applied with
+ * pure_app_deliver from the wire's source with the send's number, so an
+ * answer that comes again after a restart is applied once. */
+typedef struct {
+ uint32_t input;
+ uint64_t seq;
+ PureSpan payload;
+ const uint32_t *placed;
+ const char *source;
+} PureWireAnswer;
+bool pure_wire_answer(PureWire *, PureWireAnswer *out);
+/* Counts for a host's report. */
+void pure_wire_counts(PureWire *, uint64_t *delivered, uint64_t *attempts);
+#endif
diff --git a/serve/message-json.c b/serve/message-json.c
new file mode 100644
index 0000000..66c812d
--- /dev/null
+++ b/serve/message-json.c
@@ -0,0 +1,281 @@
+#include "message-json.h"
+#include "module-text.h"
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static void write_u32(unsigned char *p, uint32_t v) { for (unsigned i = 0; i < 4; ++i) p[i] = (unsigned char)(v >> (8 * i)); }
+
+static bool decimal(const char *text, uint64_t maximum, uint64_t *value) {
+ if (!*text) return false;
+ uint64_t n = 0;
+ for (; *text; ++text) {
+ if (*text < '0' || *text > '9') return false;
+ unsigned digit = (unsigned)(*text - '0');
+ if (n > (maximum - digit) / 10) return false;
+ n = n * 10 + digit;
+ }
+ *value = n;
+ return true;
+}
+
+/* A JSON number's text: -?(0|[1-9][0-9]*)(.[0-9]+)?([eE][+-]?[0-9]+)?, its
+ * length (0 if there is none). An integer has neither part after it. */
+static size_t json_number(const unsigned char *p, size_t size, bool *integer) {
+ size_t i = 0;
+ *integer = true;
+ if (i < size && p[i] == '-') ++i;
+ if (i == size || p[i] < '0' || p[i] > '9') return 0;
+ if (p[i++] != '0') while (i < size && p[i] >= '0' && p[i] <= '9') ++i;
+ if (i < size && p[i] == '.') {
+ *integer = false;
+ if (++i == size || p[i] < '0' || p[i] > '9') return 0;
+ while (i < size && p[i] >= '0' && p[i] <= '9') ++i;
+ }
+ if (i < size && (p[i] == 'e' || p[i] == 'E')) {
+ *integer = false;
+ if (++i < size && (p[i] == '+' || p[i] == '-')) ++i;
+ if (i == size || p[i] < '0' || p[i] > '9') return 0;
+ while (i < size && p[i] >= '0' && p[i] <= '9') ++i;
+ }
+ return i;
+}
+
+/* A fixed field's value from its text (a query value or a JSON number) into
+ * the prefix: a u32 in range, or a finite number. */
+bool pure_json_fixed(const PureField *field, const unsigned char *text, size_t size, unsigned char *prefix) {
+ bool integer;
+ if (!size || json_number(text, size, &integer) != size || size > 40) return false;
+ char digits[48];
+ memcpy(digits, text, size);
+ digits[size] = 0;
+ if (field->type == PURE_FIELD_U32) {
+ uint64_t n;
+ if (!integer || !decimal(digits, UINT32_MAX, &n)) return false;
+ write_u32(prefix + field->offset, (uint32_t)n);
+ return true;
+ }
+ double value = strtod(digits, NULL);
+ if (!isfinite(value)) return false;
+ memcpy(prefix + field->offset, &value, 8);
+ return true;
+}
+
+/* A JSON string's contents (after its opening quote) up to the closing one:
+ * its length, or 0 when it does not close or holds a control byte. */
+static size_t json_string_end(const unsigned char *p, size_t size) {
+ for (size_t i = 0; i < size; ++i) {
+ /* Eight bytes at a time while none is a quote, a backslash or a control byte. */
+ const uint64_t ones = UINT64_C(0x0101010101010101), highs = UINT64_C(0x8080808080808080);
+ for (uint64_t w, q, s; size - i >= 8; i += 8) {
+ memcpy(&w, p + i, 8);
+ q = w ^ (ones * '"');
+ s = w ^ (ones * '\\');
+ if (((q - ones) & ~q & highs) | ((s - ones) & ~s & highs) | ((w - ones * 0x20) & ~w & highs)) break;
+ }
+ if (i == size) break;
+ if (p[i] == '"') return i + 1;
+ if (p[i] < 0x20) return 0;
+ if (p[i] == '\\' && ++i == size) return 0;
+ }
+ return 0;
+}
+
+static int hex_digit(unsigned char c) {
+ return c >= '0' && c <= '9' ? c - '0' : c >= 'a' && c <= 'f' ? c - 'a' + 10 : c >= 'A' && c <= 'F' ? c - 'A' + 10 : -1;
+}
+
+static bool json_code(const unsigned char *p, size_t left, uint32_t *code) {
+ if (left < 4) return false;
+ *code = 0;
+ for (int i = 0; i < 4; ++i) {
+ int d = hex_digit(p[i]);
+ if (d < 0) return false;
+ *code = *code << 4 | (uint32_t)d;
+ }
+ return true;
+}
+
+/* Unescape a JSON string's contents into out (never longer); false for a
+ * bad escape or a lone surrogate. The result is checked as UTF-8 after. */
+static bool json_unescape(const unsigned char *in, size_t size, unsigned char *out, size_t *written) {
+ size_t o = 0;
+ for (size_t i = 0; i < size;) {
+ unsigned char b = in[i++];
+ if (b != '\\') { out[o++] = b; continue; }
+ if (i == size) return false;
+ b = in[i++];
+ const char *plain = strchr("\"\\/bfnrt", b);
+ if (b && plain) { out[o++] = (unsigned char)"\"\\/\b\f\n\r\t"[plain - "\"\\/bfnrt"]; continue; }
+ uint32_t code, low;
+ if (b != 'u' || !json_code(in + i, size - i, &code)) return false;
+ i += 4;
+ if (code >= 0xDC00 && code <= 0xDFFF) return false;
+ if (code >= 0xD800 && code <= 0xDBFF) {
+ if (size - i < 6 || in[i] != '\\' || in[i + 1] != 'u' || !json_code(in + i + 2, size - i - 2, &low) ||
+ low < 0xDC00 || low > 0xDFFF) return false;
+ i += 6;
+ code = 0x10000 + ((code - 0xD800) << 10) + (low - 0xDC00);
+ }
+ if (code < 0x80) out[o++] = (unsigned char)code;
+ else if (code < 0x800) { out[o++] = (unsigned char)(0xC0 | code >> 6); out[o++] = (unsigned char)(0x80 | (code & 0x3F)); }
+ else if (code < 0x10000) {
+ out[o++] = (unsigned char)(0xE0 | code >> 12);
+ out[o++] = (unsigned char)(0x80 | (code >> 6 & 0x3F));
+ out[o++] = (unsigned char)(0x80 | (code & 0x3F));
+ } else {
+ out[o++] = (unsigned char)(0xF0 | code >> 18);
+ out[o++] = (unsigned char)(0x80 | (code >> 12 & 0x3F));
+ out[o++] = (unsigned char)(0x80 | (code >> 6 & 0x3F));
+ out[o++] = (unsigned char)(0x80 | (code & 0x3F));
+ }
+ }
+ *written = o;
+ return true;
+}
+
+size_t pure_json_space(const unsigned char *p, size_t at, size_t size) {
+ while (at < size && (p[at] == ' ' || p[at] == '\t' || p[at] == '\n' || p[at] == '\r')) ++at;
+ return at;
+}
+
+/* Skip any JSON value at json[*at] (at most 64 deep): a member of an
+ * answer that names no field. */
+static bool skip_value(const unsigned char *json, size_t size, size_t *at, unsigned depth) {
+ if (*at == size || depth > 64) return false;
+ unsigned char b = json[*at];
+ bool integer;
+ if (b == '"') {
+ size_t end = json_string_end(json + *at + 1, size - *at - 1);
+ if (!end) return false;
+ *at += 1 + end;
+ return true;
+ }
+ if (b == '{' || b == '[') {
+ unsigned char close = b == '{' ? '}' : ']';
+ *at = pure_json_space(json, *at + 1, size);
+ for (bool first = true; *at < size && json[*at] != close; first = false) {
+ if (!first) {
+ if (json[(*at)++] != ',') return false;
+ *at = pure_json_space(json, *at, size);
+ }
+ if (close == '}') {
+ size_t key_end = *at < size && json[*at] == '"' ? json_string_end(json + *at + 1, size - *at - 1) : 0;
+ if (!key_end) return false;
+ *at = pure_json_space(json, *at + 1 + key_end, size);
+ if (*at == size || json[(*at)++] != ':') return false;
+ *at = pure_json_space(json, *at, size);
+ }
+ if (!skip_value(json, size, at, depth + 1)) return false;
+ *at = pure_json_space(json, *at, size);
+ }
+ if (*at == size) return false;
+ ++*at;
+ return true;
+ }
+ static const char *const words[] = {"true", "false", "null"};
+ for (size_t w = 0; w < 3; ++w)
+ if (size - *at >= strlen(words[w]) && !memcmp(json + *at, words[w], strlen(words[w]))) {
+ *at += strlen(words[w]);
+ return true;
+ }
+ size_t length = json_number(json + *at, size - *at, &integer);
+ *at += length;
+ return length > 0;
+}
+
+/* The field named path.key (key alone at the top), or the field count when
+ * none is; group says whether fields are named inside it instead. */
+static uint32_t field_named(const PureJsonMessage *b, const char *path, size_t path_size, const unsigned char *key,
+ size_t key_size, bool *group) {
+ const PureModule *m = b->module;
+ size_t size = path_size + !!path_size + key_size;
+ *group = false;
+ for (uint32_t f = 0; f < b->shape->field_count; ++f) {
+ const char *name = m->field[b->shape->field_start + f].name;
+ size_t length = strlen(name);
+ if (length < size || memcmp(name, path, path_size) || (path_size && name[path_size] != '.') ||
+ memcmp(name + path_size + !!path_size, key, key_size)) continue;
+ if (length == size) return f;
+ if (name[size] == '.') *group = true;
+ }
+ return b->shape->field_count;
+}
+
+/* An object's members from json[*at] (its opening brace), in the group named
+ * path: a field's value, or a group's object. Strings stay where they are
+ * (an escaped one is unescaped over itself, which never makes it longer).
+ * NULL, or the error to answer. */
+static const char *members(PureJsonMessage *b, unsigned char *json, size_t size, size_t *at, const char *path, size_t path_size,
+ unsigned depth) {
+ const PureModule *m = b->module;
+ if (*at == size || json[(*at)++] != '{') return "json";
+ *at = pure_json_space(json, *at, size);
+ for (bool first = true; *at < size && json[*at] != '}'; first = false) {
+ if (!first) {
+ if (json[(*at)++] != ',') return "json";
+ *at = pure_json_space(json, *at, size);
+ }
+ size_t key_end = *at < size && json[*at] == '"' ? json_string_end(json + *at + 1, size - *at - 1) : 0;
+ if (!key_end) return "json";
+ const unsigned char *key = json + *at + 1;
+ size_t key_size = key_end - 1;
+ *at = pure_json_space(json, *at + 1 + key_end, size);
+ if (*at == size || json[(*at)++] != ':') return "json";
+ *at = pure_json_space(json, *at, size);
+ bool group;
+ uint32_t f = field_named(b, path, path_size, key, key_size, &group);
+ if (f == b->shape->field_count && !group && b->lenient) { /* not the app's: skipped */
+ if (!skip_value(json, size, at, depth)) return "json";
+ *at = pure_json_space(json, *at, size);
+ continue;
+ }
+ if (*at < size && json[*at] == '{') {
+ if (!group) return f < b->shape->field_count ? "json_type" : "json_field";
+ char inner[PURE_MODULE_NAME];
+ size_t inner_size = path_size + !!path_size + key_size;
+ memcpy(inner, path, path_size);
+ if (path_size) inner[path_size] = '.';
+ memcpy(inner + path_size + !!path_size, key, key_size);
+ const char *why = members(b, json, size, at, inner, inner_size, depth + 1);
+ if (why) return why;
+ *at = pure_json_space(json, *at, size);
+ continue;
+ }
+ if (f == b->shape->field_count) return group ? "json_type" : "json_field";
+ if (b->seen[f] || (b->given && b->given[f])) return "json_field";
+ b->seen[f] = true;
+ const PureField *field = &m->field[b->shape->field_start + f];
+ bool variable = field->type == PURE_FIELD_BYTES || field->type == PURE_FIELD_TEXT, integer;
+ if (*at < size && json[*at] == '"') {
+ size_t end = json_string_end(json + *at + 1, size - *at - 1), written;
+ if (!end) return "json";
+ if (!variable) return "json_type";
+ unsigned char *value = json + *at + 1;
+ if (!memchr(value, '\\', end - 1)) written = end - 1;
+ else if (!json_unescape(value, end - 1, value, &written)) return "json";
+ if (field->type == PURE_FIELD_TEXT && !pure_utf8_valid((PureSpan){value, written})) return "json";
+ write_u32(b->table + 8 * f, (uint32_t)(value - b->payload));
+ write_u32(b->table + 8 * f + 4, (uint32_t)written);
+ *at = pure_json_space(json, *at + 1 + end, size);
+ continue;
+ }
+ size_t length = json_number(json + *at, size - *at, &integer);
+ if (!length) {
+ static const char *const words[] = {"true", "false", "null"};
+ for (size_t w = 0; w < 3 && !length; ++w)
+ if (size - *at >= strlen(words[w]) && !memcmp(json + *at, words[w], strlen(words[w]))) return "json_type";
+ return *at < size && json[*at] == '[' ? "json_type" : "json";
+ }
+ if (variable || !pure_json_fixed(field, json + *at, length, b->payload)) return "json_type";
+ *at = pure_json_space(json, *at + length, size);
+ }
+ if (*at == size) return "json";
+ ++*at;
+ return NULL;
+}
+
+const char *pure_json_message(PureJsonMessage *message, unsigned char *json, size_t size, size_t *at) {
+ return members(message, json, size, at, "", 0, 0);
+}
diff --git a/serve/message-json.h b/serve/message-json.h
new file mode 100644
index 0000000..61211d6
--- /dev/null
+++ b/serve/message-json.h
@@ -0,0 +1,26 @@
+#ifndef PURE_MESSAGE_JSON_H
+#define PURE_MESSAGE_JSON_H
+#include "module.h"
+
+/* A message's fields from a JSON object read in place (docs/research/082-json-in-place.md):
+ * a u32 or a number for a fixed field (put into the prefix), a string for
+ * bytes or text (left where it is: an escaped one is unescaped over itself,
+ * which never makes it longer), a group's fields as an object inside. */
+typedef struct {
+ const PureModule *module;
+ const PureInputShape *shape;
+ unsigned char *payload; /* the prefix; a string's start is counted from here */
+ unsigned char *table; /* for each field, its start and size (u32le each) */
+ const bool *given; /* fields given elsewhere (a request's query), or NULL */
+ bool lenient; /* a member naming no field is skipped, value and all (an API's answer) */
+ bool seen[PURE_MODULE_FIELDS];
+} PureJsonMessage;
+
+/* The object at json[*at] (its opening brace), *at moved past it: NULL, or
+ * what is wrong ("json", "json_field": unknown or given twice, "json_type"). */
+const char *pure_json_message(PureJsonMessage *, unsigned char *json, size_t size, size_t *at);
+size_t pure_json_space(const unsigned char *json, size_t at, size_t size);
+/* A fixed field's value from its text (a query value or a JSON number) into
+ * the prefix: a u32 in range, or a finite number. */
+bool pure_json_fixed(const PureField *field, const unsigned char *text, size_t size, unsigned char *prefix);
+#endif
diff --git a/serve/serve.c b/serve/serve.c
new file mode 100644
index 0000000..2ea7adb
--- /dev/null
+++ b/serve/serve.c
@@ -0,0 +1,1820 @@
+#define _GNU_SOURCE
+/* pure-serve: the HTTP host for aup modules (docs/research/075).
+ *
+ * An app's views and inputs are its HTTP interface, with no routes to write:
+ * GET /views/NAME answers a view (a number or text as text/plain, a table as
+ * JSON rows, ?from=N&count=M for a page of them) and POST /inputs/NAME
+ * delivers an event (a text input's text is the body; a key input is
+ * pressed, down then up; a message takes its u32 fields from the query and
+ * its bytes field from the body, and answers what its handler replies, a
+ * field of the message). A failed event answers with its fault.
+ *
+ * A module with keyed messages named show and edit also serves the document
+ * contract of server.c (GET and PUT /objects/KEY, If-Match or If-None-Match:
+ * *, ETag = revision, X-Pure-Error): GET is its show message and PUT its edit
+ * message. HTTP/1.1 connections persist and may pipeline; an epoll thread
+ * accepts, reads and writes without blocking. Requests go through the
+ * runtime core (a work slot per connection, the payload budget, ingress
+ * owned by the core, write replies borrowed from the request). After each
+ * round of events every ready request is applied to the module with
+ * deferred saving, one save stores the burst, and only then are its
+ * requests answered: an answer is durable, and a failed save fails the
+ * whole burst, reads included.
+ *
+ * With --threads N each thread has its own listener on the same port
+ * (SO_REUSEPORT), epoll set and runtime domain; the kernel spreads
+ * connections over them. A module of keyed documents alone runs one app per
+ * thread: they share nothing but the store, whose commits take turns and
+ * whose revisions settle concurrent edits of a key. States have one owner:
+ * for a module with them, one more thread owns the app, and the connection
+ * threads hand it their ready requests and answer what it hands back. Its
+ * bursts take the requests of every thread, one save each. */
+#include "deliver.h"
+#include "message-json.h"
+#include "module-store.h"
+#include "module-text.h"
+#include "runtime.h"
+#include "store.h"
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <math.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdatomic.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <poll.h>
+#include <sched.h>
+#include <sys/epoll.h>
+#include <sys/eventfd.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+#include <time.h>
+#include <unistd.h>
+
+enum { HEADER_LIMIT = 4096, EVENTS = 256, BATCH = 256 };
+typedef enum { CLOSED, READING_HEAD, READING_BODY, WAITING, WRITING } Phase;
+typedef struct Host Host;
+
+/* What a request names: a document, a view (a table's rows from, count) or
+ * an input. Kept per work slot, so an accepted event runs even if its
+ * connection is gone before the burst. */
+typedef enum { ROUTE_NONE, ROUTE_OBJECT, ROUTE_VIEW, ROUTE_INPUT } RouteKind;
+typedef struct { RouteKind kind; uint32_t target; size_t from, count; } Route;
+
+/* Allocated when accepted and reused after closing: memory follows the
+ * connections that are open, not the configured maximum. */
+typedef struct Connection {
+ Host *host;
+ struct Connection *next; /* on the spare or the closed list */
+ size_t index; /* in the host's table */
+ int fd;
+ Phase phase;
+ bool readable, writable, keep_alive, put, post;
+ uint64_t deadline;
+ char key[65]; /* the document's key, or the view's or input's name */
+ RouteKind route;
+ /* An app input's message: its fixed fields from the query, which fields
+ * were given there, and whether the body is a JSON object of the rest.
+ * Its ingress is [u32le payload size][payload]; with JSON it is [u32le
+ * payload size | PLACED][u32le start and size of each field][payload: the
+ * prefix, then the JSON as it came], its strings read where they are. */
+ unsigned char fields[8 * PURE_MODULE_FIELDS];
+ size_t field_bytes;
+ bool given[PURE_MODULE_FIELDS], json;
+ uint32_t input;
+ unsigned char *ingress;
+ char source[PURE_SOURCE + 1]; /* a delivered message's sender (X-Pure-Source), or empty */
+ uint64_t sequence; /* and its number (X-Pure-Sequence) */
+ unsigned batch; /* how many numbered messages the body holds (X-Pure-Count) */
+ int64_t expected;
+ size_t body_size, received, in_used;
+ unsigned char *body;
+ PureTicket ticket;
+ struct iovec *out, small[4]; /* the answer: its head, then its body's extents */
+ size_t out_count, out_at;
+ char head[320];
+ char in[HEADER_LIMIT]; /* the header being read, then pipelined bytes */
+} Connection;
+
+/* One request applied in a burst, for the connection thread that answers
+ * it. A read answered from the store lends its extents: they point into a
+ * store mapping, which the resource holds and the runtime charges and
+ * releases with the ticket. */
+typedef struct {
+ Host *host;
+ PureTicket ticket;
+ PureInput input;
+ PureResult status;
+ int64_t revision;
+ PureResource resource;
+ PureSpan reply;
+ struct iovec *extents;
+ size_t extent_count;
+ char key[65];
+ RouteKind route;
+ PureFault fault; /* a failed event's */
+ const char *type; /* a view's content type */
+} Applied;
+
+/* The app and its store. A connection thread runs it itself (an app of
+ * documents only), or one owner thread runs it for all connection threads.
+ * The owner publishes a snapshot of the states after each save, and the
+ * connection threads show views from it themselves: reads never wait for
+ * the owner, which may be applying events or waiting for a sync. */
+typedef struct {
+ const PureModule *module;
+ PureStore *store;
+ PureApp app;
+ uint32_t show, edit;
+ uint64_t bursts, burst_events;
+ Applied *applied; /* a round's requests, grown to fit */
+ size_t applied_capacity;
+ bool wrote; /* the last round saved an event or an edit */
+ bool reads_first; /* the owner's: a round's reads before its writes */
+ double next[PURE_MODULE_INPUTS]; /* when each timer ticks next (wall clock, ms) */
+ uint64_t ticks;
+ /* The owner's: the last save's snapshot (NULL: the owner shows views),
+ * taken under the lock, and the app's changes it shows. */
+ bool publishes;
+ pthread_mutex_t published_lock;
+ PureSnapshot *published;
+ uint64_t published_changes, publications;
+ /* The owner's: outputs wired to HTTP receivers, and how far each was trimmed. */
+ PureWire *wires[PURE_MODULE_INPUTS];
+ unsigned wire_count;
+ uint64_t trimmed[PURE_MODULE_INPUTS], answers;
+ bool held[PURE_MODULE_INPUTS]; /* an answer failed to apply: the wire's sends stay until a restart */
+} Executor;
+
+/* A request made ready: its effect, what it names, and the thread that answers it. */
+typedef struct { Host *host; PureEffect effect; Route route; } Job;
+
+/* The owner of an app with states served by several connection threads:
+ * their requests wait here, and it runs them in bursts, one save each
+ * however many threads they came from, handing each thread back its
+ * applied requests to answer. */
+typedef struct {
+ Executor executor;
+ pthread_mutex_t lock;
+ pthread_cond_t waiting;
+ Job *jobs;
+ size_t count, capacity;
+ uint64_t arrivals; /* requests handed to the owner, ever */
+ bool stopping;
+ bool delivered; /* a wire delivered a send: trim it */
+ Host *hosts;
+ unsigned host_count;
+} Owner;
+
+struct Host {
+ const PureModule *module;
+ bool documents; /* the module serves /objects: it has show and edit */
+ Executor local; /* the app, when this thread runs it */
+ Owner *owner; /* or the owner that runs it */
+ PureApp reader; /* shows the owner's snapshot here */
+ Applied *views; /* a round's views shown here, answered together */
+ size_t views_capacity;
+ uint64_t shown; /* views shown from snapshots */
+ Route *routes; /* by work slot */
+ PureRuntime runtime;
+ PureWork *work;
+ Connection **table; /* open connections by index */
+ Connection **by_slot; /* the connection waiting on a work slot */
+ Connection *spare, *closed;
+ Job *jobs; /* a round's requests: at most one per work slot */
+ size_t capacity, active;
+ int epoll, listener;
+ uint64_t timeout_ms;
+ uint64_t accepted, requests, expired;
+ /* What the owner hands back to answer (swapped for answering), and the
+ * eventfd that says so; pending counts requests at the owner. */
+ pthread_mutex_t lock;
+ Applied *done, *answering;
+ size_t done_count, done_capacity, answering_capacity, pending;
+ int wake;
+};
+
+/* Grow an array to hold `need` items; false when memory runs out. */
+static bool grow(void *array, size_t *capacity, size_t need, size_t size) {
+ if (need <= *capacity) return true;
+ size_t next = *capacity ? *capacity : 64;
+ while (next < need) next *= 2;
+ void *grown = realloc(*(void **)array, next * size);
+ if (!grown) return false;
+ *(void **)array = grown;
+ *capacity = next;
+ return true;
+}
+
+static atomic_bool stopping; /* lock-free, so a signal handler may set it */
+static void stop(int signal_number) { (void)signal_number; atomic_store(&stopping, true); }
+
+static uint64_t now_ms(void) {
+ struct timespec t;
+ clock_gettime(CLOCK_MONOTONIC, &t);
+ return (uint64_t)t.tv_sec * 1000 + (uint64_t)t.tv_nsec / 1000000;
+}
+
+/* The time events see: the wall clock, in milliseconds since 1970 (UTC). */
+static double wall_ms(void) {
+ struct timespec t;
+ clock_gettime(CLOCK_REALTIME, &t);
+ return floor((double)t.tv_sec * 1000 + (double)t.tv_nsec / 1e6);
+}
+
+static bool number(const char *text, uint64_t maximum, uint64_t *value) {
+ if (!*text) return false;
+ uint64_t n = 0;
+ for (; *text; ++text) {
+ if (*text < '0' || *text > '9') return false;
+ unsigned digit = (unsigned)(*text - '0');
+ if (n > (maximum - digit) / 10) return false;
+ n = n * 10 + digit;
+ }
+ *value = n;
+ return true;
+}
+
+/* ---- Connections ------------------------------------------------------ */
+
+static void release_ticket(void *owner) {
+ Connection *c = owner;
+ if (c->ticket.runtime && !pure_runtime_release(c->ticket)) abort();
+ c->ticket = (PureTicket){0};
+ c->body = NULL;
+}
+
+/* Everything an answer borrowed goes back with its ticket: the request's
+ * payload, a copied reply or the lent store extents. */
+static void finish_output(Connection *c) {
+ release_ticket(c);
+ if (c->out != c->small) free(c->out);
+ c->out = NULL;
+ c->out_count = c->out_at = 0;
+}
+
+/* Events of this round may still name c: it is reused after the round. */
+static void close_connection(Connection *c) {
+ if (c->phase == CLOSED) return;
+ Host *host = c->host;
+ finish_output(c);
+ close(c->fd); /* also leaves the epoll set */
+ c->phase = CLOSED;
+ host->table[c->index] = NULL;
+ c->next = host->closed;
+ host->closed = c;
+ --host->active;
+}
+
+/* Answer with a body of `count` extents (`size` bytes in all); the ticket
+ * keeps them alive. One writev sends as much as the socket takes. */
+static void respond_typed(Connection *c, int status, const char *reason, const char *error, int64_t revision,
+ const char *type, const struct iovec *extents, size_t count, size_t size) {
+ char tag[48] = "";
+ if (revision > 0) snprintf(tag, sizeof(tag), "ETag: \"%" PRId64 "\"\r\n", revision);
+ /* A delivery's answer tells how many numbered messages one request may carry. */
+ char batch[32] = "";
+ if (*c->source) snprintf(batch, sizeof(batch), "X-Pure-Batch: %d\r\n", BATCH);
+ int length = snprintf(c->head, sizeof(c->head),
+ "HTTP/1.1 %d %s\r\nContent-Length: %zu\r\n%sContent-Type: %s\r\n"
+ "Cache-Control: no-store\r\nX-Pure-Error: %s\r\n%s%s\r\n",
+ status, reason, size, c->keep_alive ? "" : "Connection: close\r\n", type, error, tag, batch);
+ c->out = count < sizeof(c->small) / sizeof(*c->small) ? c->small : malloc((count + 1) * sizeof(*c->out));
+ c->phase = WRITING;
+ if (!c->out) { c->keep_alive = false; c->out = c->small; count = 0; } /* cannot send it: the close tells */
+ c->out[0] = (struct iovec){c->head, (size_t)length};
+ if (count) memcpy(c->out + 1, extents, count * sizeof(*extents));
+ c->out_count = count + 1;
+ c->out_at = 0;
+}
+
+static void respond_extents(Connection *c, int status, const char *reason, const char *error, int64_t revision,
+ const struct iovec *extents, size_t count, size_t size) {
+ respond_typed(c, status, reason, error, revision, "application/octet-stream", extents, count, size);
+}
+
+static void respond(Connection *c, int status, const char *reason, const char *error, int64_t revision,
+ PureSpan body) {
+ struct iovec extent = {(void *)body.data, body.size};
+ respond_extents(c, status, reason, error, revision, &extent, body.size ? 1 : 0, body.size);
+}
+
+/* A request refused before it has a ticket; a body it came with is not read. */
+static void reject(Connection *c, int status, const char *reason, const char *error) {
+ if (c->body_size) c->keep_alive = false;
+ respond(c, status, reason, error, 0, (PureSpan){0});
+}
+
+/* A request the host cannot read further: answer and close. */
+static void refuse(Connection *c, int status, const char *reason, const char *error) {
+ release_ticket(c);
+ c->keep_alive = false;
+ respond(c, status, reason, error, 0, (PureSpan){0});
+}
+
+static void answer(Connection *c, PureOutcome result) {
+ switch (result.status) {
+ case PURE_OK: respond(c, 200, "OK", "none", result.revision, result.body); return;
+ case PURE_CONFLICT: respond(c, 412, "Precondition Failed", "conflict", result.revision, (PureSpan){0}); return;
+ case PURE_NOT_FOUND: respond(c, 404, "Not Found", "not_found", 0, (PureSpan){0}); break;
+ case PURE_BUSY: respond(c, 503, "Service Unavailable", "store_busy", 0, (PureSpan){0}); break;
+ case PURE_BUDGET: respond(c, 503, "Service Unavailable", "payload_budget", 0, (PureSpan){0}); break;
+ case PURE_ALLOCATION: respond(c, 503, "Service Unavailable", "allocation", 0, (PureSpan){0}); break;
+ case PURE_CLOSED: respond(c, 503, "Service Unavailable", "stopped", 0, (PureSpan){0}); break;
+ case PURE_DENIED: respond(c, 403, "Forbidden", "denied", 0, (PureSpan){0}); break;
+ case PURE_LIMIT: respond(c, 413, "Content Too Large", "limit", 0, (PureSpan){0}); break;
+ case PURE_UNCERTAIN: respond(c, 500, "Internal Server Error", "durability_unknown", 0, (PureSpan){0}); break;
+ default: respond(c, 500, "Internal Server Error", "storage", 0, (PureSpan){0}); break;
+ }
+ /* A failed request carries no body: the payload can go now. */
+ if (!result.body.size) release_ticket(c);
+}
+
+static const char *const fault_names[] = {"none", "divide", "non_finite", "clamp", "limit", "not_found", "encoding",
+ "exists"};
+
+/* An app route's answer: a view's value, or what an event replied. A failed
+ * event names its fault: 404 not_found, 409 exists, 422 for the others;
+ * a view without a value is 404 no_value. */
+static void answer_app(Connection *c, PureOutcome result, bool view, PureFault fault, const char *type) {
+ const char *named = fault != PURE_FAULT_NONE ? fault_names[fault] : NULL;
+ if (result.status == PURE_OK) {
+ struct iovec extent = {(void *)result.body.data, result.body.size};
+ respond_typed(c, 200, "OK", "none", 0, type ? type : "application/octet-stream", &extent,
+ result.body.size ? 1 : 0, result.body.size);
+ } else if (result.status == PURE_NOT_FOUND) {
+ respond(c, 404, "Not Found", view ? "no_value" : named ? named : "not_found", 0, (PureSpan){0});
+ } else if (result.status == PURE_CONFLICT) {
+ respond(c, 409, "Conflict", named ? named : "conflict", 0, (PureSpan){0});
+ } else if (named && (result.status == PURE_LIMIT || result.status == PURE_INVALID)) {
+ respond(c, 422, "Unprocessable Content", named, 0, (PureSpan){0});
+ } else if (result.status == PURE_INVALID) {
+ respond(c, 400, "Bad Request", "invalid", 0, (PureSpan){0}); /* such as a text that is not UTF-8 */
+ } else {
+ answer(c, result);
+ return;
+ }
+ if (!result.body.size) release_ticket(c);
+}
+
+/* Parse one request head of `size` bytes (through the blank line): the same
+ * bounded HTTP/1.1 subset as server.c, plus Connection, POST and the app
+ * routes. A query stays in head for start_request; an unknown path is
+ * answered 404 once its head is read. */
+static bool parse_head(Connection *c, char *head, size_t size, char **query) {
+ for (size_t i = 0; i < size; ++i) {
+ unsigned char b = (unsigned char)head[i];
+ if ((b < 32 && b != '\r' && b != '\n' && b != '\t') || b == 127) return false;
+ }
+ head[size - 2] = 0; /* keep the last CRLF of the last header */
+ char *line = head, *next = strstr(line, "\r\n");
+ if (!next) return false;
+ *next = 0;
+ char *path = strchr(line, ' ');
+ if (!path) return false;
+ *path++ = 0;
+ c->put = !strcmp(line, "PUT");
+ c->post = !strcmp(line, "POST");
+ if (!c->put && !c->post && strcmp(line, "GET")) return false;
+ char *version = strchr(path, ' ');
+ if (!version) return false;
+ *version++ = 0;
+ if (strcmp(version, "HTTP/1.1")) return false;
+ if ((*query = strchr(path, '?'))) *(*query)++ = 0;
+ static const struct { const char *prefix; RouteKind kind; } routes[] = {
+ {"/objects/", ROUTE_OBJECT}, {"/views/", ROUTE_VIEW}, {"/inputs/", ROUTE_INPUT}};
+ const char *key = "";
+ c->route = ROUTE_NONE;
+ for (size_t i = 0; i < sizeof(routes) / sizeof(*routes) && c->route == ROUTE_NONE; ++i)
+ if (!strncmp(path, routes[i].prefix, strlen(routes[i].prefix))) {
+ c->route = routes[i].kind;
+ key = path + strlen(routes[i].prefix);
+ }
+ size_t key_size = strlen(key);
+ if (c->route != ROUTE_NONE && (!key_size || key_size > 64)) return false;
+ for (size_t i = 0; i < key_size; ++i) {
+ char b = key[i];
+ if (!((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || (b >= '0' && b <= '9') || b == '-' || b == '_'))
+ return false;
+ }
+ memcpy(c->key, key, key_size + 1);
+ /* Each route has its method: documents GET and PUT, views GET, inputs POST. */
+ if ((c->route == ROUTE_OBJECT && (c->post || *query)) || (c->route == ROUTE_VIEW && (c->put || c->post)) ||
+ (c->route == ROUTE_INPUT && !c->post)) return false;
+ bool length_seen = false, condition_seen = false, host_seen = false;
+ c->source[0] = 0;
+ c->sequence = 0;
+ c->batch = 1;
+ bool counted = false;
+ c->body_size = 0;
+ c->json = false;
+ c->expected = -1;
+ c->keep_alive = true;
+ line = next + 2;
+ while (*line) {
+ next = strstr(line, "\r\n");
+ if (!next) return false;
+ *next = 0;
+ char *value = strchr(line, ':');
+ if (!value || value == line) return false;
+ *value++ = 0;
+ for (char *p = line; *p; ++p)
+ if (!((*p >= 'a' && *p <= 'z') || (*p >= 'A' && *p <= 'Z') || (*p >= '0' && *p <= '9') || *p == '-'))
+ return false;
+ while (*value == ' ' || *value == '\t') ++value;
+ char *tail = value + strlen(value);
+ while (tail > value && (tail[-1] == ' ' || tail[-1] == '\t')) *--tail = 0;
+ uint64_t n;
+ if (!strcasecmp(line, "Content-Length")) {
+ if (length_seen || !number(value, SIZE_MAX, &n)) return false;
+ length_seen = true;
+ c->body_size = (size_t)n;
+ } else if (!strcasecmp(line, "Host")) {
+ if (host_seen || !*value) return false;
+ host_seen = true;
+ } else if (!strcasecmp(line, "If-Match")) {
+ if (condition_seen || tail - value < 3 || *value != '"' || tail[-1] != '"') return false;
+ tail[-1] = 0;
+ if (!number(value + 1, INT64_MAX, &n) || !n) return false;
+ c->expected = (int64_t)n;
+ condition_seen = true;
+ } else if (!strcasecmp(line, "If-None-Match")) {
+ if (condition_seen || strcmp(value, "*")) return false;
+ c->expected = 0;
+ condition_seen = true;
+ } else if (!strcasecmp(line, "Content-Type")) {
+ c->json = !strncasecmp(value, "application/json", 16);
+ } else if (!strcasecmp(line, "Connection")) {
+ if (!strcasecmp(value, "close")) c->keep_alive = false;
+ else if (strcasecmp(value, "keep-alive")) return false;
+ } else if (!strcasecmp(line, "X-Pure-Source")) {
+ /* A message delivered from another app's output: applied once per number. */
+ size_t length = strlen(value);
+ if (*c->source || !length || length > PURE_SOURCE) return false;
+ for (size_t i = 0; i < length; ++i) if (value[i] <= ' ' || value[i] > '~') return false;
+ memcpy(c->source, value, length + 1);
+ } else if (!strcasecmp(line, "X-Pure-Sequence")) {
+ if (c->sequence || !number(value, UINT64_MAX, &n) || !n) return false;
+ c->sequence = n;
+ } else if (!strcasecmp(line, "X-Pure-Count")) {
+ /* Numbered messages from X-Pure-Sequence on, as a JSON array. */
+ if (counted || !number(value, BATCH, &n) || !n) return false;
+ c->batch = (unsigned)n;
+ counted = true;
+ } else if (!strcasecmp(line, "Transfer-Encoding") || !strcasecmp(line, "Expect")) return false;
+ line = next + 2;
+ }
+ if (!*c->source != !c->sequence || (*c->source && c->route != ROUTE_INPUT) || (counted && !*c->source) ||
+ c->sequence > UINT64_MAX - c->batch) return false;
+ if (c->put) return host_seen && length_seen && condition_seen;
+ if (c->post) return host_seen && !condition_seen; /* no Content-Length: no body */
+ return host_seen && !condition_seen && c->body_size == 0;
+}
+
+static void put_u32(unsigned char *p, uint32_t v) { for (unsigned i = 0; i < 4; ++i) p[i] = (unsigned char)(v >> (8 * i)); }
+static void put_u64(unsigned char *p, uint64_t v) { for (unsigned i = 0; i < 8; ++i) p[i] = (unsigned char)(v >> (8 * i)); }
+static uint32_t get_u32(const unsigned char *p) { return p[0] | p[1] << 8 | (uint32_t)p[2] << 16 | (uint32_t)p[3] << 24; }
+static uint64_t get_u64(const unsigned char *p) { return get_u32(p) | (uint64_t)get_u32(p + 4) << 32; }
+
+/* What an app route names in the module, with a message's fixed fields
+ * taken from the query into c->fields. NULL, or the error to answer (404
+ * for a name the module lacks, 400 otherwise). */
+static const char *resolve(const Host *host, Connection *c, char *query, Route *route, int *status) {
+ const PureModule *m = host->module;
+ *status = 404;
+ c->field_bytes = 0;
+ memset(c->given, 0, sizeof(c->given));
+ if (route->kind == ROUTE_NONE || (route->kind == ROUTE_OBJECT && !host->documents)) return "route";
+ if (route->kind == ROUTE_OBJECT) return NULL;
+ int found = route->kind == ROUTE_VIEW ? pure_module_view(m, c->key) : pure_module_input(m, c->key);
+ /* An output is the app's to send and a timer ticks by itself: neither is posted. */
+ if (found >= 0 && route->kind == ROUTE_INPUT &&
+ (m->input[found].kind == PURE_KIND_OUTPUT || m->input[found].kind == PURE_KIND_TIMER)) found = -1;
+ if (found < 0) return route->kind == ROUTE_VIEW ? "no_view" : "no_input";
+ *status = 400;
+ route->target = (uint32_t)found;
+ route->from = 0;
+ route->count = SIZE_MAX;
+ const PureInputShape *shape = route->kind == ROUTE_INPUT ? &m->input[found] : NULL;
+ bool message = shape && shape->kind == PURE_KIND_MESSAGE;
+ if (message && shape->keyed) return "keyed";
+ if (*c->source && !message) return "delivery";
+ if (!host->owner) c->source[0] = 0; /* an app without states or outputs applies it as a message */
+ if (shape) {
+ /* A body is a text input's text, a message's one variable field, or a
+ * JSON object of a message's fields (two variable fields need one). */
+ unsigned variables = 0;
+ for (uint32_t f = 0; message && f < shape->field_count; ++f)
+ variables += m->field[shape->field_start + f].type == PURE_FIELD_BYTES ||
+ m->field[shape->field_start + f].type == PURE_FIELD_TEXT;
+ if (c->json && !message) return "json";
+ if (!c->json && (variables > 1 || (c->body_size && shape->kind == PURE_KIND_KEY) ||
+ (c->body_size && message && !variables))) return variables > 1 ? "json" : "body";
+ c->input = (uint32_t)found;
+ c->field_bytes = message ? shape->prefix : 0;
+ }
+ /* name=value pairs: a table's from and count, a message's fixed fields. */
+ for (char *pair = query; pair && *pair;) {
+ char *end = strchr(pair, '&'), *value = strchr(pair, '=');
+ if (end) *end = 0;
+ if (!value || (end && value > end)) return "query";
+ *value++ = 0;
+ if (route->kind == ROUTE_VIEW) {
+ uint64_t n;
+ bool from = !strcmp(pair, "from");
+ if (!number(value, SIZE_MAX, &n) || m->view_type[found] != PURE_VIEW_TABLE || (!from && strcmp(pair, "count")))
+ return "query";
+ if (from) route->from = (size_t)n;
+ else route->count = (size_t)n;
+ } else {
+ uint32_t f = 0;
+ while (f < (message ? shape->field_count : 0) && strcmp(m->field[shape->field_start + f].name, pair)) ++f;
+ const PureField *field = message && f < shape->field_count ? &m->field[shape->field_start + f] : NULL;
+ if (!field || c->given[f] || (field->type != PURE_FIELD_U32 && field->type != PURE_FIELD_NUMBER) ||
+ !pure_json_fixed(field, (const unsigned char *)value, strlen(value), c->fields)) return "query";
+ c->given[f] = true;
+ }
+ pair = end ? end + 1 : NULL;
+ }
+ for (uint32_t f = 0; message && !c->json && f < shape->field_count; ++f) {
+ uint8_t type = m->field[shape->field_start + f].type;
+ if ((type == PURE_FIELD_U32 || type == PURE_FIELD_NUMBER) && !c->given[f]) return "missing_field";
+ }
+ for (uint32_t f = 0; c->batch > 1 && f < shape->field_count; ++f)
+ if (c->given[f]) return "delivery"; /* a batch's fields are all in its objects */
+ if (c->batch > 1 && !c->json) return "delivery";
+ if (!*c->source) c->batch = 1;
+ return NULL;
+}
+
+/* Parsing a JSON body in place: the payload it is in, the placed fields'
+ * table, and which fields it gave. */
+#define PLACED (UINT32_C(1) << 31)
+/* After the size: a delivered message's number (u64le), how many follow it
+ * (u32le: a batch) and its source (u8 length and the bytes), in DELIVERY
+ * bytes before the tables; then a table for each message, a prefix for each
+ * and the JSON. */
+#define DELIVERED (UINT32_C(1) << 30)
+enum { DELIVERY = 80 };
+/* An app input's JSON body becomes its message: an object with a member for
+ * each field the query did not give (a u32, a number, or a string for bytes
+ * and text), groups as objects inside it, and nothing else. Fixed fields go
+ * into the prefix; strings stay in the body, and the table says where.
+ * NULL, or the error to answer. */
+static const char *convert(Connection *c) {
+ const PureInputShape *shape = &c->host->module->input[c->input];
+ uint32_t delivered = get_u32(c->ingress) & DELIVERED;
+ size_t table = 8 * (size_t)shape->field_count;
+ unsigned char *tables = c->ingress + 4 + (delivered ? DELIVERY : 0), *prefixes = tables + c->batch * table;
+ unsigned char *json = c->body;
+ size_t size = c->body_size, at = pure_json_space(json, 0, size);
+ /* A batch is an array of its messages' objects. */
+ if (c->batch > 1) {
+ if (at == size || json[at++] != '[') return "json";
+ at = pure_json_space(json, at, size);
+ }
+ for (unsigned i = 0; i < c->batch; ++i) {
+ if (i) {
+ if (at == size || json[at++] != ',') return "json";
+ at = pure_json_space(json, at, size);
+ }
+ PureJsonMessage b = {.module = c->host->module, .shape = shape, .table = tables + i * table,
+ .payload = prefixes + i * c->field_bytes, .given = c->given};
+ const char *why = pure_json_message(&b, json, size, &at);
+ if (why) return why;
+ at = pure_json_space(json, at, size);
+ for (uint32_t f = 0; f < shape->field_count; ++f)
+ if (!b.seen[f] && !c->given[f]) return "missing_field";
+ }
+ if (c->batch > 1 && (at == size || json[at++] != ']')) return "json";
+ if (pure_json_space(json, at, size) != size) return "json";
+ put_u32(c->ingress, (uint32_t)(c->batch * c->field_bytes + c->body_size) | PLACED | delivered);
+ return NULL;
+}
+
+/* A request's body is in: an app input's JSON becomes its payload, and the
+ * request is ready, or it is answered 400 and never runs. */
+static void body_done(Connection *c) {
+ const char *why = c->route == ROUTE_INPUT && c->json ? convert(c) : NULL;
+ if (why) {
+ release_ticket(c); /* never made ready: it never runs */
+ respond(c, 400, "Bad Request", why, 0, (PureSpan){0});
+ return;
+ }
+ if (!pure_runtime_ready(c->ticket)) abort();
+ c->phase = WAITING;
+}
+
+/* A whole head is in `in`: admit the request and take any body bytes that
+ * came with it; later bytes stay for the next request. */
+static void start_request(Connection *c, size_t head_size) {
+ Host *host = c->host;
+ char head[HEADER_LIMIT], *query = NULL;
+ memcpy(head, c->in, head_size);
+ size_t extra = c->in_used - head_size;
+ memmove(c->in, c->in + head_size, extra);
+ c->in_used = extra;
+ if (!parse_head(c, head, head_size, &query)) { refuse(c, 400, "Bad Request", "request"); return; }
+ if (c->body_size > PURE_OBJECT_LIMIT) { refuse(c, 413, "Content Too Large", "limit"); return; }
+ ++host->requests;
+ Route route = {.kind = c->route};
+ int status;
+ const char *why = resolve(host, c, query, &route, &status);
+ if (why) { reject(c, status, status == 404 ? "Not Found" : "Bad Request", why); return; }
+ /* A document's PUT carries its body; an input's event its payload's size,
+ * the payload (the fixed fields, then the body), and room for its JSON. */
+ bool write = route.kind == ROUTE_INPUT || c->put;
+ size_t table = route.kind == ROUTE_INPUT && c->json ? 8 * (size_t)host->module->input[c->input].field_count : 0;
+ size_t lead = 4 + (route.kind == ROUTE_INPUT && *c->source ? DELIVERY : 0);
+ /* A batch has a table and a prefix for each of its messages. */
+ size_t input_size = route.kind == ROUTE_INPUT ? lead + c->batch * (table + c->field_bytes) + c->body_size :
+ write ? c->body_size : 0;
+ PureResult admitted = pure_runtime_accept(&host->runtime, write ? PURE_INPUT_WRITE : PURE_INPUT_READ, c->key,
+ route.kind == ROUTE_INPUT ? 0 : c->expected, input_size, &c->ticket);
+ if (admitted != PURE_OK) {
+ c->ticket = (PureTicket){0};
+ /* An unread body would desynchronize the stream. */
+ if (c->body_size) c->keep_alive = false;
+ answer(c, (PureOutcome){.status = admitted});
+ return;
+ }
+ host->by_slot[c->ticket.slot] = c;
+ host->routes[c->ticket.slot] = route;
+ if (!write) { c->phase = WAITING; return; }
+ unsigned char *ingress = c->ingress = pure_runtime_ingress(c->ticket, NULL); /* NULL for no bytes */
+ c->body = ingress;
+ if (route.kind == ROUTE_INPUT) {
+ put_u32(ingress, (uint32_t)(c->batch * c->field_bytes + c->body_size) | (lead > 4 ? DELIVERED : 0));
+ if (lead > 4) {
+ size_t length = strlen(c->source);
+ put_u64(ingress + 4, c->sequence);
+ put_u32(ingress + 12, c->batch);
+ ingress[16] = (unsigned char)length;
+ memcpy(ingress + 17, c->source, length);
+ }
+ if (c->field_bytes) memcpy(ingress + lead + c->batch * table, c->fields, c->field_bytes);
+ c->body = ingress + lead + c->batch * (table + c->field_bytes);
+ }
+ size_t take = c->in_used < c->body_size ? c->in_used : c->body_size;
+ if (take) memcpy(c->body, c->in, take);
+ memmove(c->in, c->in + take, c->in_used - take);
+ c->in_used -= take;
+ c->received = take;
+ c->phase = READING_BODY;
+ if (c->received == c->body_size) body_done(c);
+}
+
+static size_t head_end(const Connection *c) {
+ for (size_t i = 3; i < c->in_used; ++i)
+ if (!memcmp(c->in + i - 3, "\r\n\r\n", 4)) return i + 1;
+ return 0;
+}
+
+/* Advance a connection as far as its socket allows without blocking. */
+static void drive(Connection *c) {
+ for (;;) {
+ if (c->phase == READING_HEAD) {
+ size_t end = head_end(c);
+ if (end) { start_request(c, end); continue; }
+ if (c->in_used == HEADER_LIMIT) { refuse(c, 431, "Request Header Fields Too Large", "headers"); continue; }
+ if (!c->readable) return;
+ ssize_t n = recv(c->fd, c->in + c->in_used, HEADER_LIMIT - c->in_used, 0);
+ if (n > 0) { c->in_used += (size_t)n; c->deadline = now_ms() + c->host->timeout_ms; continue; }
+ if (n < 0 && errno == EAGAIN) { c->readable = false; return; }
+ if (n < 0 && errno == EINTR) continue;
+ close_connection(c);
+ return;
+ }
+ if (c->phase == READING_BODY) {
+ if (!c->readable) return;
+ ssize_t n = recv(c->fd, c->body + c->received, c->body_size - c->received, 0);
+ if (n > 0) {
+ c->received += (size_t)n;
+ c->deadline = now_ms() + c->host->timeout_ms;
+ if (c->received == c->body_size) body_done(c);
+ continue;
+ }
+ if (n < 0 && errno == EAGAIN) { c->readable = false; return; }
+ if (n < 0 && errno == EINTR) continue;
+ close_connection(c);
+ return;
+ }
+ if (c->phase == WRITING) {
+ if (!c->writable) return;
+ size_t left = c->out_count - c->out_at;
+ ssize_t n = writev(c->fd, c->out + c->out_at, (int)(left < IOV_MAX ? left : IOV_MAX));
+ if (n < 0 && errno == EAGAIN) { c->writable = false; return; }
+ if (n < 0 && errno == EINTR) continue;
+ if (n < 0) { close_connection(c); return; }
+ c->deadline = now_ms() + c->host->timeout_ms; /* a slow reader is fine while it reads */
+ for (size_t sent = (size_t)n; c->out_at < c->out_count;) {
+ struct iovec *v = &c->out[c->out_at];
+ if (sent < v->iov_len) {
+ v->iov_base = (char *)v->iov_base + sent;
+ v->iov_len -= sent;
+ break;
+ }
+ sent -= v->iov_len;
+ ++c->out_at;
+ }
+ if (c->out_at < c->out_count) continue;
+ /* Answered: the next request may already be here. */
+ finish_output(c);
+ c->deadline = now_ms() + c->host->timeout_ms;
+ if (!c->keep_alive) { close_connection(c); return; }
+ c->phase = READING_HEAD;
+ continue;
+ }
+ return; /* WAITING: the next burst answers */
+ }
+}
+
+/* ---- Bursts ----------------------------------------------------------- */
+
+static void release_copy(void *allocation, size_t size) {
+ (void)size;
+ free(allocation);
+}
+
+static void release_loan(void *allocation, size_t size) {
+ (void)size;
+ pure_mapping_release(allocation);
+}
+
+static bool allocate_ingress(void *context, size_t size, PureResource *out) {
+ (void)context;
+ void *bytes = malloc(size ? size : 1); /* a key press or an empty text has no payload */
+ if (!bytes) return false;
+ *out = (PureResource){.body = {bytes, size}, .allocation = bytes, .allocation_size = size, .release = release_copy};
+ return true;
+}
+
+typedef struct { unsigned char *bytes; size_t size; const unsigned char *first; size_t spans; } Reply;
+
+static bool measure_reply(void *context, PureSpan span) {
+ Reply *r = context;
+ if (!r->spans++) r->first = span.data;
+ r->size += span.size;
+ return true;
+}
+
+/* A value's extents, if the store mapping holds every one. */
+typedef struct { struct iovec *extents; size_t count, capacity; const PureMapping *mapping; bool held; } Gather;
+
+static bool gather_extents(void *context, PureSpan span) {
+ Gather *g = context;
+ if (!span.size) return true;
+ g->held = g->held && pure_mapping_holds(g->mapping, span) &&
+ grow(&g->extents, &g->capacity, g->count + 1, sizeof(*g->extents));
+ if (g->held) g->extents[g->count++] = (struct iovec){(void *)span.data, span.size};
+ return g->held;
+}
+
+/* A gathered value goes out as the mapping's extents, not copied: the answer
+ * holds the mapping (charged to the budget) until it is sent and its ticket
+ * released. false (and nothing held) when some extent was not stored. */
+static bool lend(Applied *out, PureMapping *mapping, Gather *gather, bool read, size_t size) {
+ if (!read || !gather->held) {
+ free(gather->extents);
+ pure_mapping_release(mapping);
+ return false;
+ }
+ out->extents = gather->extents;
+ out->extent_count = gather->count;
+ out->resource = (PureResource){.body = {NULL, size}, .allocation = mapping, .allocation_size = size,
+ .release = release_loan};
+ return true;
+}
+
+static bool copy_reply(void *context, PureSpan span) {
+ Reply *r = context;
+ if (span.size) memcpy(r->bytes + r->size, span.data, span.size);
+ r->size += span.size;
+ return true;
+}
+
+/* ---- App routes -------------------------------------------------------- */
+
+typedef struct { unsigned char *bytes; size_t size, capacity; bool failed; } Output;
+
+static bool put_bytes(Output *o, const void *bytes, size_t size) {
+ if (o->failed) return false;
+ if (size > o->capacity - o->size) {
+ size_t capacity = o->capacity ? o->capacity : 256;
+ while (capacity - o->size < size) {
+ if (capacity > SIZE_MAX / 2) { o->failed = true; return false; }
+ capacity *= 2;
+ }
+ unsigned char *grown = realloc(o->bytes, capacity);
+ if (!grown) { o->failed = true; return false; }
+ o->bytes = grown;
+ o->capacity = capacity;
+ }
+ if (size) memcpy(o->bytes + o->size, bytes, size);
+ o->size += size;
+ return true;
+}
+
+static bool put_span(void *context, PureSpan span) { return put_bytes(context, span.data, span.size); }
+
+/* A JSON string's contents: quotes, backslashes and control bytes escaped,
+ * other bytes (UTF-8, which Pure keeps valid) as they are. */
+static bool put_json_span(void *context, PureSpan span) {
+ Output *o = context;
+ const unsigned char *p = span.data;
+ size_t plain = 0;
+ for (size_t i = 0; i < span.size; ++i) {
+ unsigned char b = p[i];
+ if (b >= 0x20 && b != '"' && b != '\\') continue;
+ char escape[8];
+ int length = b == '"' || b == '\\' ? snprintf(escape, sizeof(escape), "\\%c", b) :
+ snprintf(escape, sizeof(escape), "\\u%04x", b);
+ put_bytes(o, p + plain, i - plain);
+ put_bytes(o, escape, (size_t)length);
+ plain = i + 1;
+ }
+ return put_bytes(o, p + plain, span.size - plain);
+}
+
+static void put_number(Output *o, double value) {
+ char digits[32];
+ put_bytes(o, digits, pure_format_number(value, digits));
+}
+
+/* A view's value: a number in Pure's shortest form or a text, as text; a
+ * table as {"rows":N,"from":F,"items":[{column: value}...]} for the rows
+ * asked, each cell computed only for them (a cell without a value is null). */
+static PureResult show_view(PureApp *app, const Route *route, size_t available, Applied *answer) {
+ const PureModule *m = app->module;
+ uint32_t view = route->target;
+ PureResource *out = &answer->resource;
+ const char **type = &answer->type;
+ /* Room for a page of short rows at once. */
+ Output o = {0};
+ PureResult status = PURE_OK;
+ double value;
+ if (m->view_type[view] == PURE_VIEW_TABLE && !(o.bytes = malloc(o.capacity = 1024))) return PURE_ALLOCATION;
+ if (m->view_type[view] == PURE_VIEW_NUM) {
+ *type = "text/plain; charset=utf-8";
+ if (pure_app_view(app, view, &value)) put_number(&o, value);
+ else status = PURE_NOT_FOUND;
+ } else if (m->view_type[view] == PURE_VIEW_TEXT) {
+ *type = "text/plain; charset=utf-8";
+ /* A text state shown as it is goes out as its stored extents. */
+ int state = pure_module_text_state(m, view);
+ PureDraft *text = state >= 0 ? app->texts[state] : NULL;
+ PureVersion version = text ? pure_draft_version(text) : (PureVersion){0, 0};
+ if (version.bytes > available) return PURE_BUDGET;
+ PureMapping *mapping = version.bytes ? pure_draft_mapping(text) : NULL;
+ if (mapping) {
+ Gather gather = {NULL, 0, 0, mapping, true};
+ bool read = pure_draft_read_version(text, version, 0, (size_t)version.bytes, gather_extents, &gather) == PURE_OK;
+ if (lend(answer, mapping, &gather, read, (size_t)version.bytes)) return PURE_OK;
+ }
+ status = pure_app_view_text(app, view, put_span, &o);
+ } else {
+ *type = "application/json";
+ size_t rows = pure_app_rows(app, view), from = route->from < rows ? route->from : rows;
+ size_t end = from + (route->count < rows - from ? route->count : rows - from);
+ /* Each column's key, ,"name": (the first row's first without the comma), made once. */
+ struct { uint32_t view; size_t length; char key[PURE_MODULE_NAME + 4]; } columns[PURE_MODULE_VIEWS];
+ unsigned count = 0;
+ for (uint32_t column = 0; column < m->views; ++column)
+ if (m->view_table[column] == view + 1) {
+ columns[count].view = column;
+ columns[count].length = (size_t)snprintf(columns[count].key, sizeof(columns[count].key), ",\"%s\":",
+ m->view_names[column]);
+ ++count;
+ }
+ char head[80];
+ put_bytes(&o, head, (size_t)snprintf(head, sizeof(head), "{\"rows\":%zu,\"from\":%zu,\"items\":[", rows, from));
+ for (size_t row = from; row < end && !o.failed; ++row) {
+ put_bytes(&o, ",{" + (row == from), 2 - (row == from));
+ for (unsigned k = 0; k < count; ++k) {
+ put_bytes(&o, columns[k].key + !k, columns[k].length - !k);
+ if (m->view_type[columns[k].view] == PURE_VIEW_NUM) {
+ if (pure_app_cell(app, columns[k].view, row, &value)) put_number(&o, value);
+ else put_bytes(&o, "null", 4);
+ continue;
+ }
+ size_t mark = o.size;
+ put_bytes(&o, "\"", 1);
+ if (pure_app_cell_text(app, columns[k].view, row, put_json_span, &o) == PURE_OK) put_bytes(&o, "\"", 1);
+ else if (!o.failed) {
+ o.size = mark;
+ put_bytes(&o, "null", 4);
+ }
+ }
+ put_bytes(&o, "}", 1);
+ }
+ put_bytes(&o, "]}", 2);
+ }
+ if (status == PURE_OK && !o.bytes && !(o.bytes = malloc(1))) o.failed = true; /* an empty value has a buffer too */
+ if (status == PURE_OK && o.failed) status = PURE_ALLOCATION;
+ if (status == PURE_OK && o.size > available) status = PURE_BUDGET;
+ if (status != PURE_OK) {
+ free(o.bytes);
+ return status;
+ }
+ *out = (PureResource){.body = {o.bytes, o.size}, .allocation = o.bytes, .allocation_size = o.size,
+ .release = release_copy};
+ return PURE_OK;
+}
+
+/* An input's event: a text, a key pressed (down, then up), or a message
+ * whose reply (a field of it) is borrowed from the request. */
+static PureResult apply_input(PureApp *app, const Route *route, const PureEffect *effect, Applied *out) {
+ const PureInputShape *shape = &app->module->input[route->target];
+ uint32_t header = get_u32(effect->value.data);
+ const unsigned char *delivery = effect->value.data + 4;
+ unsigned batch = header & DELIVERED ? get_u32(delivery + 8) : 1;
+ size_t lead = 4 + (header & DELIVERED ? DELIVERY : 0), table = header & PLACED ? 8 * (size_t)shape->field_count : 0;
+ PureSpan payload = {effect->value.data + lead + batch * table, header & ~(PLACED | DELIVERED)};
+ PureResult status;
+ if (shape->kind == PURE_KIND_TEXT) {
+ status = pure_app_text(app, route->target, payload);
+ } else if (shape->kind == PURE_KIND_KEY) {
+ status = pure_app_input(app, route->target, PURE_EDGE_DOWN);
+ if (status == PURE_OK) status = pure_app_input(app, route->target, PURE_EDGE_UP);
+ } else {
+ uint32_t placed[2 * PURE_MODULE_FIELDS];
+ for (size_t i = 0; table && i < 2 * (size_t)shape->field_count; ++i)
+ placed[i] = get_u32(effect->value.data + lead + 4 * i);
+ if (header & DELIVERED) {
+ char source[PURE_SOURCE + 1];
+ memcpy(source, delivery + 13, delivery[12]);
+ source[delivery[12]] = 0;
+ status = pure_app_deliver(app, route->target, source, get_u64(delivery), payload, table ? placed : NULL);
+ /* The rest of a batch, in order: an app's refusal was heard and the
+ * batch goes on; another failure stops it, to be sent again. */
+ for (unsigned i = 1; i < batch && (status == PURE_OK || app->fault != PURE_FAULT_NONE); ++i) {
+ const unsigned char *at = effect->value.data + lead + i * table;
+ for (size_t k = 0; k < 2 * (size_t)shape->field_count; ++k) placed[k] = get_u32(at + 4 * k);
+ PureSpan next = {payload.data + i * shape->prefix, payload.size - i * shape->prefix};
+ status = pure_app_deliver(app, route->target, source, get_u64(delivery) + i, next, placed);
+ }
+ if (batch > 1 && app->fault != PURE_FAULT_NONE) status = PURE_OK;
+ } else
+ status = table ? pure_app_message_fields(app, route->target, NULL, -1, payload, placed) :
+ pure_app_message(app, route->target, NULL, -1, payload);
+ Reply reply = {0};
+ if (status == PURE_OK) pure_app_reply(app, measure_reply, &reply);
+ out->reply = (PureSpan){reply.size ? reply.first : NULL, reply.size};
+ }
+ out->fault = app->fault;
+ return status;
+}
+
+static void apply_effect(Executor *ex, const Job *job, Applied *out) {
+ PureApp *app = &ex->app;
+ const PureEffect *effect = &job->effect;
+ app->now = wall_ms();
+ *out = (Applied){.host = job->host, .ticket = effect->ticket, .input = effect->input, .route = job->route.kind};
+ memcpy(out->key, effect->key, strlen(effect->key) + 1);
+ if (job->route.kind == ROUTE_VIEW) {
+ out->status = show_view(app, &job->route, effect->available, out);
+ return;
+ }
+ if (job->route.kind == ROUTE_INPUT) {
+ out->status = apply_input(app, &job->route, effect, out);
+ if (out->status == PURE_OK) ++ex->burst_events;
+ return;
+ }
+ bool read = effect->input == PURE_INPUT_READ;
+ out->status = pure_app_message(app, read ? ex->show : ex->edit, effect->key,
+ read ? -1 : effect->expected, read ? (PureSpan){0} : effect->value);
+ out->revision = app->revision;
+ if (out->status != PURE_OK) return;
+ ++ex->burst_events;
+ Reply reply = {0};
+ pure_app_reply(app, measure_reply, &reply);
+ if (!read) {
+ /* Checked at start: an edit replies a field of its request. */
+ out->reply = (PureSpan){reply.size ? reply.first : NULL, reply.size};
+ return;
+ }
+ if (reply.size > effect->available) { out->status = PURE_BUDGET; return; }
+ if (!reply.size) return;
+ /* A stored document is lent, extent by extent, not copied. */
+ PureMapping *mapping = app->document ? pure_draft_mapping(app->document) : NULL;
+ if (mapping) {
+ Gather gather = {NULL, 0, 0, mapping, true};
+ bool read = pure_app_reply(app, gather_extents, &gather) == PURE_OK;
+ if (lend(out, mapping, &gather, read, reply.size)) return;
+ }
+ unsigned char *copy = malloc(reply.size);
+ if (!copy) { out->status = PURE_ALLOCATION; return; }
+ reply = (Reply){.bytes = copy};
+ pure_app_reply(app, copy_reply, &reply);
+ out->resource = (PureResource){.body = {copy, reply.size}, .allocation = copy, .allocation_size = reply.size,
+ .release = release_copy};
+}
+
+/* After a save, before its answers go: from now on views show what it
+ * saved, so a read made after a write's answer sees the write. A failed save
+ * returns the app to the last save's states, which the snapshot still shows. */
+static void publish(Executor *ex) {
+ if (!ex->publishes || (ex->published && ex->published_changes == ex->app.changes)) return;
+ PureSnapshot *made = pure_app_snapshot(&ex->app), *old;
+ pthread_mutex_lock(&ex->published_lock);
+ old = ex->published;
+ ex->published = made;
+ pthread_mutex_unlock(&ex->published_lock);
+ pure_snapshot_release(old);
+ ex->published_changes = ex->app.changes;
+ ++ex->publications;
+}
+
+/* The saved sends of wired outputs not queued yet go to their wires, in
+ * order; a wire that cannot take one takes the rest at a later save. The
+ * outbox is looked at newest first, only as far back as the new sends go,
+ * however many older ones wait for their receivers. */
+typedef struct { uint32_t wire; uint64_t seq; PureSpan payload; } Fresh;
+typedef struct { Executor *executor; Fresh *fresh; size_t count, capacity; unsigned done; bool failed; } Queueing;
+
+static bool find_fresh(void *context, uint32_t output, uint64_t seq, PureSpan payload) {
+ Queueing *q = context;
+ Executor *ex = q->executor;
+ for (unsigned i = 0; i < ex->wire_count; ++i) {
+ if (pure_wire_output(ex->wires[i]) != output || (q->done >> i & 1)) continue;
+ if (seq <= pure_wire_queued(ex->wires[i])) {
+ q->done |= 1u << i; /* older ones were queued before */
+ break;
+ }
+ if (q->count == q->capacity) {
+ size_t capacity = q->capacity ? 2 * q->capacity : 64;
+ Fresh *grown = realloc(q->fresh, capacity * sizeof(*grown));
+ if (!grown) { q->failed = true; return false; }
+ q->fresh = grown;
+ q->capacity = capacity;
+ }
+ q->fresh[q->count++] = (Fresh){i, seq, payload};
+ break;
+ }
+ return q->done != (ex->wire_count >= 32 ? UINT32_MAX : (1u << ex->wire_count) - 1);
+}
+
+static void after_save(Executor *ex) {
+ publish(ex);
+ if (!ex->wire_count) return;
+ Queueing q = {.executor = ex};
+ pure_app_outbox_newest(&ex->app, find_fresh, &q);
+ bool blocked[PURE_MODULE_INPUTS] = {false};
+ for (size_t k = q.failed ? 0 : q.count; k-- > 0;) {
+ const Fresh *f = &q.fresh[k];
+ if (!blocked[f->wire]) blocked[f->wire] = !pure_wire_queue(ex->wires[f->wire], f->seq, f->payload);
+ }
+ free(q.fresh);
+}
+
+/* The answers the wires made become events, in order; then what the wires
+ * delivered leaves the outbox (with the next save). True when an answer was
+ * applied (the caller saves). */
+static bool take_deliveries(Executor *ex) {
+ bool answered = false;
+ for (unsigned i = 0; i < ex->wire_count; ++i) {
+ PureWireAnswer answer;
+ while (pure_wire_answer(ex->wires[i], &answer)) {
+ ex->app.now = wall_ms();
+ PureResult result = pure_app_deliver(&ex->app, answer.input, answer.source, answer.seq, answer.payload,
+ answer.placed);
+ if (result != PURE_OK && ex->app.fault == PURE_FAULT_NONE) {
+ ex->held[i] = true; /* not applied and not refused: sent again after a restart */
+ fprintf(stderr, "{\"wire\":\"%s\",\"seq\":%" PRIu64 ",\"error\":\"its answer was not applied\"}\n",
+ answer.source, answer.seq);
+ }
+ pure_app_finish(&ex->app);
+ answered = true;
+ ++ex->answers;
+ }
+ uint64_t delivered = pure_wire_delivered(ex->wires[i]);
+ if (delivered <= ex->trimmed[i] || ex->held[i]) continue;
+ pure_app_trim(&ex->app, pure_wire_output(ex->wires[i]), delivered);
+ ex->trimmed[i] = delivered;
+ }
+ return answered;
+}
+
+/* One save for a burst: its requests are durable with it or fail with it. */
+static void save_burst(Executor *ex, Applied *applied, size_t count) {
+ if (!count) return;
+ for (size_t i = 0; i < count; ++i)
+ ex->wrote = ex->wrote || (applied[i].status == PURE_OK && applied[i].input == PURE_INPUT_WRITE);
+ PureResult saved = pure_app_save(&ex->app);
+ ++ex->bursts;
+ if (saved == PURE_OK) after_save(ex);
+ for (size_t i = 0; i < count; ++i)
+ if (applied[i].status == PURE_OK) applied[i].status = saved;
+}
+
+/* Run a round's requests in bursts. A burst ends before a document's key
+ * repeats or before its documents would outgrow one save, so every request
+ * is stored by its burst's save or fails with it; views and events of the
+ * app's states join any burst. Each group of answers goes to finish.
+ *
+ * The owner takes a round's reads first and answers them at once: a
+ * round's requests come from different connections (each has one request
+ * at a time), so nothing orders them, and placed before the writes the
+ * reads see only saved states (a round starts from a save). With writes
+ * going on this halves the reads' wait and doubles both rates. A single
+ * thread does not: it waits out each save itself, and reads answered first
+ * come back first, splitting its next writes over more saves (the owner
+ * gathers after a save instead). */
+static void execute(Executor *ex, const Job *jobs, size_t count, void (*finish)(void *, Applied *, size_t),
+ void *context) {
+ if (!count) return;
+ if (!grow(&ex->applied, &ex->applied_capacity, count, sizeof(*ex->applied))) abort();
+ Applied *applied = ex->applied;
+ /* One look at the store per round: a request made after another shard's
+ * answer was sent is read after that answer's commit. */
+ bool pinned = pure_store_pin(ex->store, true) == PURE_OK;
+ size_t reads = 0;
+ for (size_t i = 0; ex->reads_first && i < count; ++i)
+ if (jobs[i].effect.input == PURE_INPUT_READ) apply_effect(ex, &jobs[i], &applied[reads++]);
+ if (reads) finish(context, applied, reads);
+ size_t n = reads, start = reads, keys = 0;
+ for (size_t i = 0; i < count; ++i) {
+ if (ex->reads_first && jobs[i].effect.input == PURE_INPUT_READ) continue;
+ bool document = jobs[i].route.kind == ROUTE_OBJECT, repeated = false;
+ for (size_t k = start; k < n && document && !repeated; ++k)
+ repeated = applied[k].route == ROUTE_OBJECT && !strcmp(applied[k].key, jobs[i].effect.key);
+ if (repeated || (document && keys == PURE_APP_PENDING)) {
+ save_burst(ex, applied + start, n - start);
+ finish(context, applied + start, n - start);
+ start = n;
+ keys = 0;
+ }
+ apply_effect(ex, &jobs[i], &applied[n++]);
+ keys += document;
+ }
+ save_burst(ex, applied + start, n - start);
+ finish(context, applied + start, n - start);
+ if (pinned) pure_store_pin(ex->store, false);
+}
+
+/* Tick every timer that is due, with one save for them (an app with states
+ * only: a timer can change nothing else). The milliseconds until the next
+ * is due, or -1 without timers. Missed ticks are not made up. */
+static long run_timers(Executor *ex) {
+ const PureModule *m = ex->module;
+ if (!m->states) return -1;
+ double now = wall_ms(), soonest = -1;
+ bool ticked = false;
+ for (uint32_t i = 0; i < m->inputs; ++i) {
+ if (m->input[i].kind != PURE_KIND_TIMER) continue;
+ if (!ex->next[i]) ex->next[i] = now + m->input[i].period; /* the first period starts now */
+ if (ex->next[i] <= now) {
+ ex->app.now = now;
+ if (pure_app_tick(&ex->app, i) == PURE_OK) ++ex->ticks;
+ ticked = true;
+ ex->next[i] = now + m->input[i].period;
+ }
+ if (soonest < 0 || ex->next[i] - now < soonest) soonest = ex->next[i] - now;
+ }
+ if (ticked && pure_app_save(&ex->app) == PURE_OK) after_save(ex); /* a failed save undoes the ticks */
+ return soonest < 0 ? -1 : (long)ceil(soonest);
+}
+
+/* On the request's connection thread: complete its ticket and answer it if
+ * its connection still waits for it. */
+static void answer_applied(Host *host, Applied *a) {
+ if (!pure_runtime_complete(a->ticket, a->status, a->input == PURE_INPUT_READ ? &a->resource : NULL,
+ a->status == PURE_OK ? a->reply : (PureSpan){0}, a->revision)) abort();
+ Connection *c = host->by_slot[a->ticket.slot];
+ if (c && c->phase == WAITING && c->ticket.generation == a->ticket.generation) {
+ PureOutcome result;
+ if (!pure_runtime_result(a->ticket, &result)) abort();
+ /* A lent answer's body is its extents (the runtime charged them). */
+ if (result.status == PURE_OK && a->extents)
+ respond_typed(c, 200, "OK", "none", result.revision, a->type ? a->type : "application/octet-stream",
+ a->extents, a->extent_count, result.body.size);
+ else if (a->route != ROUTE_OBJECT) answer_app(c, result, a->route == ROUTE_VIEW, a->fault, a->type);
+ else answer(c, result);
+ drive(c); /* most answers fit the socket buffer at once */
+ }
+ free(a->extents);
+}
+
+static void answer_burst(void *context, Applied *applied, size_t count) {
+ (void)context;
+ for (size_t i = 0; i < count; ++i) answer_applied(applied[i].host, &applied[i]);
+}
+
+/* On the owner: give each connection thread its applied requests, and wake it. */
+static void hand_back(void *context, Applied *applied, size_t count) {
+ Owner *owner = context;
+ for (unsigned h = 0; h < owner->host_count; ++h) {
+ Host *host = &owner->hosts[h];
+ size_t mine = 0;
+ for (size_t i = 0; i < count; ++i) mine += applied[i].host == host;
+ if (!mine) continue;
+ pthread_mutex_lock(&host->lock);
+ if (!grow(&host->done, &host->done_capacity, host->done_count + mine, sizeof(*host->done))) abort();
+ for (size_t i = 0; i < count; ++i)
+ if (applied[i].host == host) host->done[host->done_count++] = applied[i];
+ pthread_mutex_unlock(&host->lock);
+ uint64_t one = 1;
+ if (write(host->wake, &one, sizeof(one)) != sizeof(one)) abort();
+ }
+}
+
+/* On a connection thread: answer what the owner handed back. */
+static void answer_handed(Host *host) {
+ uint64_t signals;
+ if (read(host->wake, &signals, sizeof(signals)) < 0 && errno != EAGAIN) abort();
+ pthread_mutex_lock(&host->lock);
+ Applied *done = host->done;
+ size_t count = host->done_count, capacity = host->done_capacity;
+ host->done = host->answering;
+ host->done_capacity = host->answering_capacity;
+ host->done_count = 0;
+ pthread_mutex_unlock(&host->lock);
+ host->answering = done;
+ host->answering_capacity = capacity;
+ for (size_t i = 0; i < count; ++i) answer_applied(host, &done[i]);
+ host->pending -= count;
+}
+
+/* The owner's newest snapshot, held, shown by this thread's reader; NULL
+ * when there is none. Taken for each round, after the round's answers from
+ * the owner: those were handed back after their saves' snapshots. */
+static PureSnapshot *read_published(Host *host) {
+ Executor *ex = &host->owner->executor;
+ pthread_mutex_lock(&ex->published_lock);
+ PureSnapshot *snapshot = ex->published;
+ if (snapshot) pure_snapshot_hold(snapshot);
+ pthread_mutex_unlock(&ex->published_lock);
+ if (snapshot) pure_app_read(&host->reader, snapshot);
+ return snapshot;
+}
+
+/* Every request made ready since the last round: run here, or handed to the
+ * owner. Views are shown here from the snapshot when there is one, after the
+ * rest went to the owner, which meanwhile applies and saves them. Answering
+ * may make more ready; they form the next round. */
+static void serve_bursts(Host *host) {
+ for (;;) {
+ size_t count = 0;
+ PureEffect effect;
+ while (pure_runtime_take(&host->runtime, &effect) == PURE_TAKE_EFFECT)
+ host->jobs[count++] = (Job){host, effect, host->routes[effect.ticket.slot]};
+ if (!count) return;
+ if (!host->owner) {
+ execute(&host->local, host->jobs, count, answer_burst, NULL);
+ continue;
+ }
+ PureSnapshot *snapshot = NULL;
+ size_t views = 0;
+ for (size_t i = 0; i < count; ++i) views += host->jobs[i].route.kind == ROUTE_VIEW;
+ if (views && !(snapshot = read_published(host))) views = 0; /* the owner shows them */
+ size_t handed = count - views;
+ if (handed) {
+ Owner *owner = host->owner;
+ pthread_mutex_lock(&owner->lock);
+ if (!grow(&owner->jobs, &owner->capacity, owner->count + handed, sizeof(*owner->jobs))) abort();
+ for (size_t i = 0; i < count; ++i)
+ if (!snapshot || host->jobs[i].route.kind != ROUTE_VIEW) owner->jobs[owner->count++] = host->jobs[i];
+ owner->arrivals += handed;
+ pthread_cond_signal(&owner->waiting);
+ pthread_mutex_unlock(&owner->lock);
+ host->pending += handed;
+ }
+ if (!views) return;
+ /* Shown first and answered after, as a burst is. */
+ if (!grow(&host->views, &host->views_capacity, views, sizeof(*host->views))) abort();
+ size_t shown = 0;
+ for (size_t i = 0; i < count; ++i) {
+ const Job *job = &host->jobs[i];
+ if (job->route.kind != ROUTE_VIEW) continue;
+ Applied *a = &host->views[shown++];
+ *a = (Applied){.host = host, .ticket = job->effect.ticket, .input = job->effect.input, .route = ROUTE_VIEW};
+ a->status = show_view(&host->reader, &job->route, job->effect.available, a);
+ }
+ pure_snapshot_release(snapshot); /* what answers lend holds its own mapping */
+ for (size_t i = 0; i < shown; ++i) answer_applied(host, &host->views[i]);
+ host->shown += shown;
+ }
+}
+
+/* The owner's thread: take every waiting request of every connection thread
+ * as one round, until they have all stopped. */
+static struct timespec later(struct timespec t, long nanoseconds) {
+ t.tv_sec += nanoseconds / 1000000000;
+ t.tv_nsec += nanoseconds % 1000000000;
+ if (t.tv_nsec >= 1000000000) { ++t.tv_sec; t.tv_nsec -= 1000000000; }
+ return t;
+}
+
+static bool before(struct timespec a, struct timespec b) {
+ return a.tv_sec < b.tv_sec || (a.tv_sec == b.tv_sec && a.tv_nsec < b.tv_nsec);
+}
+
+static void *run_owner(void *context) {
+ Owner *owner = context;
+ Job *spare = NULL;
+ size_t spare_capacity = 0;
+ bool gather = false;
+ uint64_t answered_at = 0; /* arrivals when the last round's answers were handed back */
+ for (;;) {
+ pthread_mutex_lock(&owner->lock);
+ /* Wait for requests, or until the next timer is due; trim what the
+ * wires delivered meanwhile. */
+ for (;;) {
+ bool delivered = owner->delivered;
+ owner->delivered = false;
+ pthread_mutex_unlock(&owner->lock);
+ long due = run_timers(&owner->executor);
+ bool answered = delivered && take_deliveries(&owner->executor);
+ pthread_mutex_lock(&owner->lock);
+ /* Answers are saved with the next round, or now if none waits. */
+ if (answered && !owner->count && !owner->stopping) {
+ pthread_mutex_unlock(&owner->lock);
+ if (pure_app_save(&owner->executor.app) == PURE_OK) after_save(&owner->executor);
+ pthread_mutex_lock(&owner->lock);
+ }
+ if (owner->count || owner->stopping) break;
+ if (owner->delivered) continue;
+ if (due < 0) {
+ pthread_cond_wait(&owner->waiting, &owner->lock);
+ continue;
+ }
+ struct timespec wake;
+ clock_gettime(CLOCK_REALTIME, &wake);
+ wake = later(wake, due * 1000000L);
+ pthread_cond_timedwait(&owner->waiting, &owner->lock, &wake);
+ }
+ /* After a round that saved, its answers bring requests back from the
+ * connection threads: gather them until none has come for 100 µs (a
+ * millisecond at most), so they share one save as they would on a
+ * single thread, where answering takes that long anyway. The quiet
+ * counts only once a request came after the answers: requests that
+ * waited out the save alone would otherwise start the next round
+ * without the clients just answered, and the clients would settle
+ * into two halves taking turns, each save carrying half of them. */
+ struct timespec now, end;
+ clock_gettime(CLOCK_REALTIME, &now);
+ end = later(now, 1000000);
+ while (gather && owner->count && !owner->stopping && before(now, end)) {
+ size_t seen = owner->count;
+ bool returned = owner->arrivals != answered_at;
+ struct timespec quiet = later(now, 100000);
+ pthread_cond_timedwait(&owner->waiting, &owner->lock, returned && before(quiet, end) ? &quiet : &end);
+ if (returned && owner->count == seen) break;
+ clock_gettime(CLOCK_REALTIME, &now);
+ }
+ if (!owner->count) {
+ pthread_mutex_unlock(&owner->lock);
+ break;
+ }
+ Job *jobs = owner->jobs;
+ size_t count = owner->count, capacity = owner->capacity;
+ owner->jobs = spare;
+ owner->capacity = spare_capacity;
+ owner->count = 0;
+ pthread_mutex_unlock(&owner->lock);
+ owner->executor.wrote = false;
+ execute(&owner->executor, jobs, count, hand_back, owner);
+ gather = owner->executor.wrote;
+ pthread_mutex_lock(&owner->lock);
+ answered_at = owner->arrivals;
+ pthread_mutex_unlock(&owner->lock);
+ spare = jobs;
+ spare_capacity = capacity;
+ }
+ free(spare);
+ return NULL;
+}
+
+/* A write's reply is borrowed from its request, so the handler of an input
+ * served by PUT or POST may reply only a field of its message. */
+static bool replies_borrow(const PureModule *m, uint32_t input) {
+ for (uint32_t h = 0; h < m->handlers; ++h) {
+ if (m->handler[h].event != 1 + 2 * input) continue;
+ const PureBlock *code = &m->handler[h].code;
+ /* A field replied as it is, or a text field as its bytes. */
+ for (uint32_t pc = code->start; pc < code->start + code->length; ++pc) {
+ if (m->code[pc].op != PURE_OP_REPLY) continue;
+ uint32_t from = pc > code->start && m->code[pc - 1].op == PURE_OP_BYTES_FROM ? pc - 1 : pc;
+ if (from == code->start || m->code[from - 1].op != PURE_OP_FIELD) return false;
+ }
+ }
+ return true;
+}
+
+/* ---- Main ------------------------------------------------------------- */
+
+static bool load_module(PureModule *m, const char *path, bool *documents, uint32_t *show_out, uint32_t *edit_out) {
+ char error[160];
+ if (pure_module_read(path, m, error, sizeof(error)) != PURE_OK) {
+ fprintf(stderr, "Module: %s\n", error);
+ return false;
+ }
+ /* Documents are served when the module has show and edit, as keyed messages. */
+ int show = pure_module_input(m, "show"), edit = pure_module_input(m, "edit");
+ *documents = show >= 0 || edit >= 0;
+ if (*documents && (show < 0 || edit < 0 || m->input[show].kind != PURE_KIND_MESSAGE || !m->input[show].keyed ||
+ m->input[edit].kind != PURE_KIND_MESSAGE || !m->input[edit].keyed)) {
+ fputs("Module: documents need keyed messages named show and edit\n", stderr);
+ return false;
+ }
+ for (uint32_t i = 0; i < m->inputs; ++i) {
+ bool served = (*documents && i == (uint32_t)edit) || (m->input[i].kind == PURE_KIND_MESSAGE && !m->input[i].keyed);
+ if (served && !replies_borrow(m, i)) {
+ fprintf(stderr, "Module: %s may reply only a field of its message\n", m->input_names[i]);
+ return false;
+ }
+ }
+ *show_out = (uint32_t)(show >= 0 ? show : 0);
+ *edit_out = (uint32_t)(edit >= 0 ? edit : 0);
+ return true;
+}
+
+static void accept_all(Host *host) {
+ for (;;) {
+ int fd = accept4(host->listener, NULL, NULL, SOCK_NONBLOCK | SOCK_CLOEXEC);
+ if (fd < 0) return;
+ if (host->active == host->capacity) { close(fd); continue; } /* full: the peer sees the close */
+ Connection *c = host->spare;
+ if (c) host->spare = c->next;
+ else if (!(c = malloc(sizeof(*c)))) { close(fd); continue; }
+ size_t index = 0;
+ while (host->table[index]) ++index; /* a free index exists: active < capacity */
+ int one = 1;
+ setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
+ c->host = host;
+ c->index = index;
+ c->fd = fd;
+ c->phase = READING_HEAD;
+ c->readable = c->writable = c->keep_alive = true;
+ c->deadline = now_ms() + host->timeout_ms;
+ c->ticket = (PureTicket){0};
+ c->out = NULL;
+ c->out_count = c->out_at = 0;
+ c->body = NULL;
+ c->in_used = 0;
+ struct epoll_event event = {.events = EPOLLIN | EPOLLOUT | EPOLLRDHUP | EPOLLET, .data.ptr = c};
+ if (epoll_ctl(host->epoll, EPOLL_CTL_ADD, fd, &event)) {
+ close(fd);
+ c->next = host->spare;
+ host->spare = c;
+ continue;
+ }
+ host->table[index] = c;
+ ++host->active;
+ ++host->accepted;
+ drive(c);
+ }
+}
+
+static bool start_executor(Executor *ex, const PureModule *module, uint32_t show, uint32_t edit, const char *store) {
+ ex->module = module;
+ ex->show = show;
+ ex->edit = edit;
+ if (pure_store_open(store, &ex->store) != PURE_OK) { fputs("Cannot open the store\n", stderr); return false; }
+ if (pure_app_start(&ex->app, module, pure_store_data(ex->store)) != PURE_OK || !pure_app_defer(&ex->app, true)) {
+ fputs("Cannot start the module on the store\n", stderr);
+ return false;
+ }
+ return true;
+}
+
+static void stop_executor(Executor *ex) {
+ pure_snapshot_release(ex->published);
+ pure_app_stop(&ex->app);
+ pure_store_close(ex->store);
+ free(ex->applied);
+}
+
+/* One connection thread: its own listener on the shared port, epoll set,
+ * runtime domain and, unless an owner runs the app for all of them, app and
+ * store handle. */
+static bool start_shard(Host *host, const PureModule *module, bool documents, uint32_t show, uint32_t edit,
+ const char *store, size_t budget, unsigned *port) {
+ host->module = module;
+ host->documents = documents;
+ host->wake = -1;
+ if (!host->owner && !start_executor(&host->local, module, show, edit, store)) return false;
+ host->work = calloc(host->capacity, sizeof(*host->work));
+ host->table = calloc(host->capacity, sizeof(*host->table));
+ host->by_slot = calloc(host->capacity, sizeof(*host->by_slot));
+ host->jobs = calloc(host->capacity, sizeof(*host->jobs));
+ host->routes = calloc(host->capacity, sizeof(*host->routes));
+ if (!host->work || !host->table || !host->by_slot || !host->jobs || !host->routes) {
+ fputs("Cannot allocate connections\n", stderr);
+ return false;
+ }
+ if (!pure_runtime_init(&host->runtime, host->work, host->capacity, host, (PureHost){.allocate = allocate_ingress},
+ budget) ||
+ !pure_runtime_enable_async(&host->runtime)) return false;
+ host->listener = socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
+ int one = 1;
+ setsockopt(host->listener, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ setsockopt(host->listener, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one));
+ struct sockaddr_in address = {.sin_family = AF_INET, .sin_port = htons((uint16_t)*port),
+ .sin_addr.s_addr = htonl(INADDR_LOOPBACK)};
+ socklen_t address_size = sizeof(address);
+ if (host->listener < 0 || bind(host->listener, (struct sockaddr *)&address, sizeof(address)) ||
+ listen(host->listener, 4096) || getsockname(host->listener, (struct sockaddr *)&address, &address_size)) {
+ perror("listen");
+ return false;
+ }
+ *port = ntohs(address.sin_port); /* the first shard picks it, the others join it */
+ host->epoll = epoll_create1(EPOLL_CLOEXEC);
+ struct epoll_event listen_event = {.events = EPOLLIN, .data.ptr = NULL};
+ if (host->epoll < 0 || epoll_ctl(host->epoll, EPOLL_CTL_ADD, host->listener, &listen_event)) {
+ perror("epoll");
+ return false;
+ }
+ /* The owner says it handed requests back through an eventfd. */
+ if (host->owner) {
+ struct epoll_event wake_event = {.events = EPOLLIN, .data.ptr = &host->wake};
+ if (pthread_mutex_init(&host->lock, NULL) || (host->wake = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC)) < 0 ||
+ epoll_ctl(host->epoll, EPOLL_CTL_ADD, host->wake, &wake_event)) {
+ perror("eventfd");
+ return false;
+ }
+ }
+ return true;
+}
+
+static void *run_shard(void *context) {
+ Host *host = context;
+ struct epoll_event events[EVENTS];
+ uint64_t next_sweep = now_ms() + 1000;
+ while (!atomic_load(&stopping)) {
+ /* A thread that runs the app ticks its timers on time. */
+ long due = host->owner ? -1 : run_timers(&host->local);
+ int ready = epoll_wait(host->epoll, events, EVENTS, due >= 0 && due < 1000 ? (int)due : 1000);
+ for (int e = 0; e < ready; ++e) {
+ Connection *c = events[e].data.ptr;
+ if (!c) { accept_all(host); continue; }
+ if (events[e].data.ptr == &host->wake) { answer_handed(host); continue; }
+ if (c->phase == CLOSED) continue;
+ if (events[e].events & EPOLLERR) { close_connection(c); continue; }
+ if (events[e].events & (EPOLLIN | EPOLLRDHUP | EPOLLHUP)) c->readable = true;
+ if (events[e].events & EPOLLOUT) c->writable = true;
+ drive(c);
+ }
+ serve_bursts(host);
+ uint64_t now = now_ms();
+ if (now >= next_sweep) {
+ next_sweep = now + 1000;
+ for (size_t i = 0; i < host->capacity; ++i) {
+ Connection *c = host->table[i];
+ if (c && c->phase != WAITING && now >= c->deadline) { ++host->expired; close_connection(c); }
+ }
+ }
+ /* The round is over: closed connections can be reused. */
+ while (host->closed) {
+ Connection *c = host->closed;
+ host->closed = c->next;
+ c->next = host->spare;
+ host->spare = c;
+ }
+ }
+ pure_runtime_stop(&host->runtime);
+ serve_bursts(host);
+ /* What the owner still runs is answered before the connections close. */
+ while (host->pending) {
+ struct pollfd wake = {host->wake, POLLIN, 0};
+ if (poll(&wake, 1, -1) > 0) answer_handed(host);
+ }
+ for (size_t i = 0; i < host->capacity; ++i) if (host->table[i]) close_connection(host->table[i]);
+ return NULL;
+}
+
+static void stop_shard(Host *host) {
+ if (!host->owner) stop_executor(&host->local);
+ pure_app_stop(&host->reader);
+ if (host->listener >= 0) close(host->listener);
+ if (host->epoll >= 0) close(host->epoll);
+ if (host->wake >= 0) close(host->wake);
+ while (host->closed) {
+ Connection *c = host->closed;
+ host->closed = c->next;
+ c->next = host->spare;
+ host->spare = c;
+ }
+ for (Connection *c = host->spare, *next; c; c = next) { next = c->next; free(c); }
+ free(host->work);
+ free(host->table);
+ free(host->by_slot);
+ free(host->jobs);
+ free(host->routes);
+ free(host->done);
+ free(host->answering);
+ free(host->views);
+}
+
+/* A wire delivered a send: the owner trims it. */
+static void wire_delivered(void *context) {
+ Owner *owner = context;
+ pthread_mutex_lock(&owner->lock);
+ owner->delivered = true;
+ pthread_cond_signal(&owner->waiting);
+ pthread_mutex_unlock(&owner->lock);
+}
+
+/* --send OUTPUT=URL: that output's saved sends go to url, from NAME.OUTPUT. */
+static bool open_wires(Executor *ex, const PureModule *m, const char *const *sends, unsigned count, const char *name) {
+ for (unsigned i = 0; i < count; ++i) {
+ const char *equals = strchr(sends[i], '=');
+ char output[PURE_MODULE_NAME], source[PURE_SOURCE + 2], error[160];
+ size_t length = equals ? (size_t)(equals - sends[i]) : 0;
+ if (!length || length >= sizeof(output)) {
+ fprintf(stderr, "--send takes OUTPUT=URL, not %s\n", sends[i]);
+ return false;
+ }
+ memcpy(output, sends[i], length);
+ output[length] = 0;
+ int written = snprintf(source, sizeof(source), "%s.%s", name, output);
+ PureWire *wire = written > 0 && written <= PURE_SOURCE ? pure_wire_open(m, output, equals + 1, source, error, sizeof(error)) : NULL;
+ if (!wire) {
+ fprintf(stderr, "--send %s: %s\n", sends[i], written > PURE_SOURCE ? "the name and output are longer than 64 bytes" : error);
+ return false;
+ }
+ for (unsigned k = 0; k < ex->wire_count; ++k)
+ if (pure_wire_output(ex->wires[k]) == pure_wire_output(wire)) {
+ fprintf(stderr, "--send %s: the output is wired already\n", sends[i]);
+ pure_wire_close(wire);
+ return false;
+ }
+ ex->wires[ex->wire_count++] = wire;
+ }
+ return true;
+}
+
+/* --reply OUTPUT=INPUT: the answers to that output's sends become INPUT's events. */
+static bool wire_replies(Executor *ex, const PureModule *m, const char *const *replies, unsigned count) {
+ for (unsigned i = 0; i < count; ++i) {
+ const char *equals = strchr(replies[i], '=');
+ char output[PURE_MODULE_NAME], error[160] = "";
+ size_t length = equals ? (size_t)(equals - replies[i]) : 0;
+ int input = equals ? pure_module_input(m, equals + 1) : -1;
+ PureWire *wire = NULL;
+ if (length && length < sizeof(output)) {
+ memcpy(output, replies[i], length);
+ output[length] = 0;
+ int index = pure_module_input(m, output);
+ for (unsigned k = 0; k < ex->wire_count && index >= 0; ++k)
+ if (pure_wire_output(ex->wires[k]) == (uint32_t)index) wire = ex->wires[k];
+ }
+ if (!wire || input < 0 || !pure_wire_reply(wire, (uint32_t)input, error, sizeof(error))) {
+ fprintf(stderr, "--reply %s: %s\n", replies[i], !wire ? "takes OUTPUT=INPUT of an output given --send" :
+ input < 0 ? "no such input" : error);
+ return false;
+ }
+ }
+ return true;
+}
+
+/* --threads auto: a connection thread for each CPU this process may run on,
+ * less the one the owner of an app with states takes. */
+static unsigned auto_threads(bool owner) {
+ cpu_set_t set;
+ long cpus = sched_getaffinity(0, sizeof(set), &set) ? sysconf(_SC_NPROCESSORS_ONLN) : CPU_COUNT(&set);
+ if (cpus < 1) cpus = 1;
+ if (owner && cpus > 1) --cpus;
+ return cpus > 256 ? 256 : (unsigned)cpus;
+}
+
+int main(int argc, char **argv) {
+ static PureModule module;
+ static Owner owner;
+ const char *module_path = NULL, *store = NULL, *name = NULL, *sends[PURE_MODULE_INPUTS], *replies[PURE_MODULE_INPUTS];
+ unsigned send_count = 0, reply_count = 0;
+ unsigned port = 8767, threads = 1;
+ size_t budget = 64u << 20, capacity = 1024;
+ uint64_t timeout_ms = 10000;
+ for (int i = 1; i < argc; i += 2) {
+ uint64_t value;
+ if (i + 1 == argc) goto usage;
+ if (!strcmp(argv[i], "--module")) module_path = argv[i + 1];
+ else if (!strcmp(argv[i], "--store")) store = argv[i + 1];
+ else if (!strcmp(argv[i], "--send") && send_count < PURE_MODULE_INPUTS) sends[send_count++] = argv[i + 1];
+ else if (!strcmp(argv[i], "--name")) name = argv[i + 1];
+ else if (!strcmp(argv[i], "--send-ca")) pure_wire_trust(argv[i + 1]);
+ else if (!strcmp(argv[i], "--reply") && reply_count < PURE_MODULE_INPUTS) replies[reply_count++] = argv[i + 1];
+ else if (!strcmp(argv[i], "--port") && number(argv[i + 1], 65535, &value)) port = (unsigned)value;
+ else if (!strcmp(argv[i], "--budget") && number(argv[i + 1], SIZE_MAX, &value) && value) budget = (size_t)value;
+ else if (!strcmp(argv[i], "--connections") && number(argv[i + 1], 1u << 20, &value) && value) capacity = (size_t)value;
+ else if (!strcmp(argv[i], "--threads") && !strcmp(argv[i + 1], "auto")) threads = 0;
+ else if (!strcmp(argv[i], "--threads") && number(argv[i + 1], 256, &value) && value) threads = (unsigned)value;
+ else if (!strcmp(argv[i], "--timeout-ms") && number(argv[i + 1], 3600000, &value) && value) timeout_ms = value;
+ else goto usage;
+ }
+ uint32_t show, edit;
+ bool documents;
+ if (!module_path || !store || !load_module(&module, module_path, &documents, &show, &edit)) goto usage;
+ if (!threads) threads = auto_threads(module.states);
+ if (pure_store_init(store) != PURE_OK) { fputs("Cannot initialize the store directory\n", stderr); return 1; }
+ signal(SIGPIPE, SIG_IGN);
+ struct sigaction stop_action = {.sa_handler = stop};
+ sigemptyset(&stop_action.sa_mask);
+ sigaction(SIGINT, &stop_action, NULL);
+ sigaction(SIGTERM, &stop_action, NULL);
+ Host *hosts = calloc(threads, sizeof(*hosts));
+ pthread_t *thread = calloc(threads, sizeof(*thread)), owner_thread;
+ if (!hosts || !thread) return 1;
+ /* States (and outputs, whose sends are the app's state) have one owner on
+ * a thread of its own, whose snapshots the connection threads read. */
+ bool outputs = false;
+ for (uint32_t i = 0; i < module.inputs; ++i) outputs = outputs || module.input[i].kind == PURE_KIND_OUTPUT;
+ bool owned = module.states || outputs;
+ /* The sender's name: --name, or the module file's name without .pmod. */
+ char stem[PURE_SOURCE + 1];
+ if (!name) {
+ const char *base = strrchr(module_path, '/') ? strrchr(module_path, '/') + 1 : module_path;
+ size_t length = strlen(base);
+ if (length > 5 && !strcmp(base + length - 5, ".pmod")) length -= 5;
+ snprintf(stem, sizeof(stem), "%.*s", (int)length, base);
+ name = stem;
+ }
+ if (owned) {
+ if (!start_executor(&owner.executor, &module, show, edit, store) || pthread_mutex_init(&owner.lock, NULL) ||
+ pthread_cond_init(&owner.waiting, NULL) || pthread_mutex_init(&owner.executor.published_lock, NULL))
+ return 1;
+ owner.executor.reads_first = true;
+ owner.executor.publishes = true;
+ if (!open_wires(&owner.executor, &module, sends, send_count, name) ||
+ !wire_replies(&owner.executor, &module, replies, reply_count)) return 2;
+ after_save(&owner.executor); /* the snapshot, and the sends stored before */
+ for (unsigned i = 0; i < owner.executor.wire_count; ++i)
+ if (!pure_wire_start(owner.executor.wires[i], wire_delivered, &owner)) { fputs("Cannot start a wire\n", stderr); return 1; }
+ owner.hosts = hosts;
+ owner.host_count = threads;
+ }
+ for (unsigned i = 0; i < threads; ++i) {
+ hosts[i].capacity = capacity;
+ hosts[i].timeout_ms = timeout_ms;
+ hosts[i].listener = hosts[i].epoll = -1;
+ hosts[i].owner = owned ? &owner : NULL;
+ if (!start_shard(&hosts[i], &module, documents, show, edit, store, budget, &port)) return 1;
+ }
+ if (owned && pthread_create(&owner_thread, NULL, run_owner, &owner)) { fputs("Cannot start the owner\n", stderr); return 1; }
+ printf("{\"port\":%u,\"threads\":%u}\n", port, threads);
+ fflush(stdout);
+ for (unsigned i = 1; i < threads; ++i)
+ if (pthread_create(&thread[i], NULL, run_shard, &hosts[i])) { fputs("Cannot start a thread\n", stderr); return 1; }
+ run_shard(&hosts[0]);
+ for (unsigned i = 1; i < threads; ++i) pthread_join(thread[i], NULL);
+ if (owned) {
+ pthread_mutex_lock(&owner.lock);
+ owner.stopping = true;
+ pthread_cond_signal(&owner.waiting);
+ pthread_mutex_unlock(&owner.lock);
+ pthread_join(owner_thread, NULL);
+ }
+ size_t active = 0, retained = 0;
+ uint64_t accepted = 0, requests = 0, bursts = owner.executor.bursts, events = owner.executor.burst_events, expired = 0,
+ ticks = owner.executor.ticks, shown = 0;
+ for (unsigned i = 0; i < threads; ++i) {
+ shown += hosts[i].shown;
+ active += hosts[i].active;
+ retained += hosts[i].runtime.retained;
+ accepted += hosts[i].accepted;
+ requests += hosts[i].requests;
+ bursts += hosts[i].local.bursts;
+ events += hosts[i].local.burst_events;
+ ticks += hosts[i].local.ticks;
+ expired += hosts[i].expired;
+ stop_shard(&hosts[i]);
+ }
+ uint64_t delivered = 0, attempts = 0;
+ for (unsigned i = 0; i < owner.executor.wire_count; ++i) {
+ uint64_t d, a;
+ pure_wire_counts(owner.executor.wires[i], &d, &a);
+ delivered += d;
+ attempts += a;
+ pure_wire_close(owner.executor.wires[i]); /* what was not delivered stays in the outbox */
+ }
+ if (owned) {
+ stop_executor(&owner.executor);
+ free(owner.jobs);
+ }
+ unsigned long groups, grouped;
+ pure_store_group_counts(&groups, &grouped);
+ fprintf(stderr, "{\"active\":%zu,\"retained_payload_bytes\":%zu,\"accepted\":%" PRIu64 ",\"requests\":%" PRIu64
+ ",\"bursts\":%" PRIu64 ",\"burst_events\":%" PRIu64 ",\"ticks\":%" PRIu64 ",\"expired\":%" PRIu64
+ ",\"threads\":%u,\"owner\":%s,\"snapshots\":%" PRIu64 ",\"views_from_snapshots\":%" PRIu64
+ ",\"delivered\":%" PRIu64 ",\"delivery_attempts\":%" PRIu64 ",\"answers\":%" PRIu64
+ ",\"commit_groups\":%lu,\"grouped_commits\":%lu}\n",
+ active, retained, accepted, requests, bursts, events, ticks, expired, threads, owned ? "true" : "false",
+ owner.executor.publications, shown, delivered, attempts, owner.executor.answers, groups, grouped);
+ free(hosts);
+ free(thread);
+ return 0;
+usage:
+ fputs("pure-serve --module FILE.pmod --store DIRECTORY [--port 8767] [--threads 1|N|auto] [--budget BYTES] "
+ "[--connections 1024] [--timeout-ms 10000] [--send OUTPUT=http[s]://host:port/path ...] [--name NAME] "
+ "[--send-ca FILE] [--reply OUTPUT=INPUT ...]\n", stderr);
+ return 2;
+}