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Diffstat (limited to 'serve/serve.c')
| -rw-r--r-- | serve/serve.c | 1820 |
1 files changed, 1820 insertions, 0 deletions
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; +} |