1 files changed, 207 insertions, 0 deletions
diff --git a/research/experiments/004-direct-document-path/document-path.c b/research/experiments/004-direct-document-path/document-path.c
new file mode 100644
index 0000000..b4d6464
--- /dev/null
+++ b/research/experiments/004-direct-document-path/document-path.c
@@ -0,0 +1,207 @@
+#define _POSIX_C_SOURCE 200809L
+/* Two separately linked versions of one durable document workload. The direct
+ * build invokes the same store primitives that the Pure host uses; the Pure
+ * build runs the prepared editor.pure program through its execution core. */
+#include "store.h"
+#ifndef DIRECT_PATH
+#include "runtime.h"
+#include "store-port.h"
+#include "embedded-plan.h"
+#endif
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#ifndef PURE_BENCH_BODY_BYTES
+#define PURE_BENCH_BODY_BYTES 8192
+#endif
+enum { BODY_BYTES = PURE_BENCH_BODY_BYTES };
+static uint64_t digest = UINT64_C(14695981039346656037);
+
+static void fail(const char *message) {
+    fprintf(stderr, "%s\n", message);
+    exit(1);
+}
+
+static void check(int condition, const char *message) {
+    if (!condition) fail(message);
+}
+
+static void hash_body(const unsigned char *body, size_t size, int64_t revision) {
+    for (size_t i = 0; i < size; ++i) {
+        digest ^= body[i];
+        digest *= UINT64_C(1099511628211);
+    }
+    digest ^= (uint64_t)revision;
+    digest *= UINT64_C(1099511628211);
+}
+
+static uint64_t nanoseconds(void) {
+    struct timespec now;
+    if (clock_gettime(CLOCK_MONOTONIC, &now)) fail("clock_gettime failed");
+    return (uint64_t)now.tv_sec * UINT64_C(1000000000) + (uint64_t)now.tv_nsec;
+}
+
+static void pattern(unsigned char *body, unsigned document) {
+    for (size_t i = 0; i < BODY_BYTES; ++i)
+        body[i] = (unsigned char)('a' + (document + i) % 26);
+}
+
+#ifdef DIRECT_PATH
+static void create(const char *store, const char *key, unsigned document,
+                   const unsigned char *expected) {
+    unsigned char *input = malloc(BODY_BYTES);
+    check(input != NULL, "direct input allocation failed");
+    pattern(input, document);
+    check(!memcmp(input, expected, BODY_BYTES), "direct input mismatch");
+    int64_t revision = 0;
+    PureResult status = pure_store_splice(store, key, 0, 0, 0,
+                                          (PureSpan){input, BODY_BYTES}, &revision);
+    check(status == PURE_OK && revision == 1, "direct create failed");
+    free(input);
+}
+
+static void edit_last(const char *store, const char *key, unsigned char replacement) {
+    unsigned char *input = malloc(1);
+    check(input != NULL, "direct edit allocation failed");
+    *input = replacement;
+    int64_t revision = 0;
+    PureResult status = pure_store_splice(store, key, 1, BODY_BYTES - 1, 1,
+                                          (PureSpan){input, 1}, &revision);
+    check(status == PURE_OK && revision == 2, "direct edit failed");
+    free(input);
+}
+
+static void read_checked(const char *store, const char *key,
+                         const unsigned char *expected, int64_t revision) {
+    PureStoredView view = {0};
+    PureResult status = pure_store_select(store, key, 0, 0, true, 0,
+                                          4u * 1024u * 1024u, &view);
+    check(status == PURE_OK && view.revision == revision &&
+          view.body.size == BODY_BYTES && !memcmp(view.body.data, expected, BODY_BYTES),
+          "direct read mismatch");
+    hash_body(view.body.data, view.body.size, revision);
+    pure_store_release(&view);
+}
+#else
+static PureRuntime runtime;
+static PureWork work[1];
+
+static PureOutcome completed(PureTicket ticket) {
+    PureOutcome result;
+    while (!pure_runtime_result(ticket, &result))
+        check(pure_runtime_step(&runtime), "runtime made no progress");
+    return result;
+}
+
+static void write_checked(const char *key, int64_t expected_revision,
+                          size_t offset, size_t remove, size_t insert_size,
+                          unsigned document, unsigned char replacement,
+                          const unsigned char *expected_reply, int64_t revision) {
+    PureTicket ticket;
+    check(pure_runtime_accept(&runtime, PURE_INPUT_WRITE, key, expected_revision,
+                              8 + insert_size, &ticket) == PURE_OK, "runtime write admission failed");
+    size_t size = 0;
+    unsigned char *input = pure_runtime_ingress(ticket, &size);
+    check(input != NULL && size == 8 + insert_size, "runtime input loan failed");
+    for (unsigned i = 0; i < 4; ++i) {
+        input[i] = (unsigned char)(offset >> (8 * i));
+        input[4 + i] = (unsigned char)(remove >> (8 * i));
+    }
+    if (insert_size == BODY_BYTES) pattern(input + 8, document);
+    else input[8] = replacement;
+    check(pure_runtime_ready(ticket), "runtime publication failed");
+    PureOutcome result = completed(ticket);
+    check(result.status == PURE_OK && result.revision == revision &&
+          result.body.size == insert_size &&
+          !memcmp(result.body.data, expected_reply, insert_size),
+          "runtime write result mismatch");
+    check(pure_runtime_release(ticket) && !runtime.active && !runtime.retained,
+          "runtime write resource not released");
+}
+
+static void read_checked(const char *store, const char *key,
+                         const unsigned char *expected, int64_t revision) {
+    (void)store;
+    PureTicket ticket;
+    check(pure_runtime_accept(&runtime, PURE_INPUT_READ, key, 0, 0, &ticket) == PURE_OK,
+          "runtime read admission failed");
+    PureOutcome result = completed(ticket);
+    check(result.status == PURE_OK && result.revision == revision &&
+          result.body.size == BODY_BYTES && !memcmp(result.body.data, expected, BODY_BYTES),
+          "runtime read mismatch");
+    hash_body(result.body.data, result.body.size, revision);
+    check(pure_runtime_release(ticket) && !runtime.active && !runtime.retained,
+          "runtime read resource not released");
+}
+
+static void create(const char *store, const char *key, unsigned document,
+                   const unsigned char *expected) {
+    (void)store;
+    write_checked(key, 0, 0, 0, BODY_BYTES, document, 0, expected, 1);
+}
+
+static void edit_last(const char *store, const char *key, unsigned char replacement) {
+    (void)store;
+    write_checked(key, 1, BODY_BYTES - 1, 1, 1, 0, replacement, &replacement, 2);
+}
+#endif
+
+int main(int argc, char **argv) {
+    if (argc != 3) fail("usage: document-path STORE DOCUMENT_COUNT");
+    char *end = NULL;
+    unsigned long parsed = strtoul(argv[2], &end, 10);
+    check(end && !*end && parsed > 0 && parsed <= 4096,
+          "DOCUMENT_COUNT must be 1..4096");
+    unsigned documents = (unsigned)parsed;
+    check(pure_store_init(argv[1]) == PURE_OK, "store initialization failed");
+    unsigned char *expected = malloc(BODY_BYTES);
+    check(expected != NULL, "expected document allocation failed");
+#ifndef DIRECT_PATH
+    check(pure_embedded_program.splice && pure_embedded_program.write.offset == 8 &&
+          pure_embedded_program.splice_offset.value == 0 &&
+          pure_embedded_program.splice_remove.value == 4 &&
+          pure_embedded_program.reply_input && pure_embedded_program.read.to_end,
+          "prepared editor.pure no longer matches direct baseline");
+    check(pure_runtime_init(&runtime, work, 1, &pure_embedded_program,
+                            pure_store_host(argv[1]), 4u * 1024u * 1024u),
+          "runtime initialization failed");
+#endif
+    uint64_t start = nanoseconds();
+    uint64_t stages[4] = {0};
+    for (unsigned document = 0; document < documents; ++document) {
+        char key[16];
+        snprintf(key, sizeof(key), "doc%04u", document);
+        pattern(expected, document);
+        uint64_t before = nanoseconds();
+        create(argv[1], key, document, expected);
+        stages[0] += nanoseconds() - before;
+        before = nanoseconds();
+        read_checked(argv[1], key, expected, 1);
+        stages[1] += nanoseconds() - before;
+        unsigned char replacement = (unsigned char)('A' + document % 26);
+        before = nanoseconds();
+        edit_last(argv[1], key, replacement);
+        stages[2] += nanoseconds() - before;
+        expected[BODY_BYTES - 1] = replacement;
+        before = nanoseconds();
+        read_checked(argv[1], key, expected, 2);
+        stages[3] += nanoseconds() - before;
+    }
+    uint64_t elapsed = nanoseconds() - start;
+    free(expected);
+    printf("{\"variant\":\"%s\",\"documents\":%u,\"operations\":%u,"
+           "\"body_bytes\":%u,\"elapsed_ns\":%" PRIu64 ","
+           "\"stage_ns\":[%" PRIu64 ",%" PRIu64 ",%" PRIu64 ",%" PRIu64 "],"
+           "\"digest\":\"%016" PRIx64 "\"}\n",
+#ifdef DIRECT_PATH
+           "direct",
+#else
+           "pure",
+#endif
+           documents, documents * 4, (unsigned)BODY_BYTES, elapsed,
+           stages[0], stages[1], stages[2], stages[3], digest);
+    return 0;
+}