Function tf_index_worker_probe

tests/test_main.c:220–303

Fast real-process probes for the async index-supervisor contract. They run * only in a child admitted by the exact build-bound worker grammar. */

/* Fast real-process probes for the async index-supervisor contract. They run
 * only in a child admitted by the exact build-bound worker grammar. */
static void tf_index_worker_probe(const char *args_json, const char *response_out) {
    if (!args_json || !strstr(args_json, "\"__cbm_test_worker\"")) {
        return;
    }
    if (strstr(args_json, "\"clean\"")) {
        FILE *response = response_out ? cbm_fopen(response_out, "wb") : NULL;
        if (response) {
            (void)fputs("{\"probe\":\"clean\"}", response);
            (void)fclose(response);
        }
        (void)fprintf(stderr, "async worker clean probe\n");
        fflush(NULL);
        _Exit(response ? 0 : 1);
    }
    if (strstr(args_json, "\"crash\"")) {
        (void)fprintf(stderr, "async worker crash probe\n");
        fflush(NULL);
        abort();
    }
    if (strstr(args_json, "\"buffered-kill\"")) {
        /* The 0-byte-worker-log repro. tf_maybe_run_index_worker has already
         * put stderr into the FULL buffering a redirected stderr gets from the
         * Windows CRT (see there), so this line only reaches the log if the
         * production worker-log entry made the stream crash-durable.
         *
         * Then die the way the reports die. NOT abort(): Darwin's abort() runs
         * the stdio cleanup handler, so it flushes the very buffer this probe
         * exists to strand — under abort the reverted build still produced a
         * populated log and the repro was silently toothless. SIGKILL cannot be
         * caught, blocked or handled, so no cleanup of any kind runs. It is
         * also literally #1070's death (`signal=9`) and how #1130's hung worker
         * is terminated. */
        cbm_log_info("index.worker.buffered_kill_probe", "phase", "before_kill");
#ifdef _WIN32
        TerminateProcess(GetCurrentProcess(), 9);
#else
        (void)raise(SIGKILL);
#endif
        _Exit(2); /* unreachable: neither primitive returns */
    }
    if (strstr(args_json, "\"oversize\"")) {
        FILE *response = response_out ? cbm_fopen(response_out, "wb") : NULL;
        bool written = false;
        if (response) {
            written =
                fseek(response, (long)CBM_DAEMON_RUNTIME_APPLICATION_PAYLOAD_MAX, SEEK_SET) == 0 &&
                fputc('x', response) != EOF;
            written = fclose(response) == 0 && written;
        }
        (void)fprintf(stderr, "async worker oversized response probe\n");
        fflush(NULL);
        _Exit(written ? 0 : 1);
    }
    if (strstr(args_json, "\"hang-tree\"")) {
        (void)signal(SIGTERM, SIG_IGN);
        long descendant = 0;
#ifndef _WIN32
        pid_t child = fork();