Function cbm_gitignore_merge

src/discover/gitignore.c:419–457

char *(*cbm_gitignore_merge_dup_hook_for_test)(const char *) = NULL;

bool cbm_gitignore_merge(cbm_gitignore_t *dst, const cbm_gitignore_t *src) {
    if (!dst) {
        return false;
    }
    if (!src || src->count == 0) {
        return true; /* nothing to merge */
    }
    int needed = dst->count + src->count;
    if (needed > dst->capacity) {
        gi_pattern_t *grown = realloc(dst->patterns, (size_t)needed * sizeof(gi_pattern_t));
        if (!grown) {
            return false; /* dst left unchanged */
        }
        dst->patterns = grown;
        dst->capacity = needed;
    }
    int start_count = dst->count;
    for (int i = 0; i < src->count; i++) {
        char *pat = cbm_gitignore_merge_dup_hook_for_test
                        ? cbm_gitignore_merge_dup_hook_for_test(src->patterns[i].pattern)
                        : strdup(src->patterns[i].pattern);
        if (!pat) {
            /* Roll back partial copies so dst is unchanged on failure (atomic
             * merge). A silent partial merge could drop the very exclude
             * pattern the caller relied on while keeping others. */
            for (int j = start_count; j < dst->count; j++) {
                free(dst->patterns[j].pattern);
            }
            dst->count = start_count;
            return false;
        }
        dst->patterns[dst->count].pattern = pat;
        dst->patterns[dst->count].negated = src->patterns[i].negated;
        dst->patterns[dst->count].dir_only = src->patterns[i].dir_only;
        dst->patterns[dst->count].rooted = src->patterns[i].rooted;
        dst->count++;
    }
    return true;
}