diff options
| -rw-r--r-- | bftw.c | 249 |
1 files changed, 172 insertions, 77 deletions
@@ -496,34 +496,159 @@ static int ftwbuf_stat(struct BFTW *ftwbuf, struct stat *sb, int fd, const char return 0; } -int bftw(const char *path, bftw_fn *fn, int nopenfd, int flags, void *ptr) { - int ret = -1, err = 0; +/** + * Holds the current state of the bftw() traversal. + */ +typedef struct { + /** bftw() callback. */ + bftw_fn *fn; + /** bftw() flags. */ + int flags; + /** bftw() callback data. */ + void *ptr; - dircache cache; - dircache_init(&cache, nopenfd); + /** The appropriate errno value, if any. */ + int error; - dircache_entry *current = NULL; + /** The cache of open directories. */ + dircache cache; + /** The current dircache entry. */ + dircache_entry *current; + /** The queue of directories left to explore. */ dirqueue queue; - dirqueue_init(&queue); - - dynstr dynpath; - dynstr_init(&dynpath); + /** The current path being explored. */ + dynstr path; + /** Extra data about the current file. */ struct BFTW ftwbuf; - ftwbuf_init(&ftwbuf, 0, 0); + /** stat() buffer for the current file. */ + struct stat statbuf; +} bftw_state; - struct stat sb; - if (ftwbuf_stat(&ftwbuf, &sb, AT_FDCWD, path) != 0) { - if (!(flags & BFTW_RECOVER)) { - goto fail; +/** + * Initialize the bftw() state. + */ +static void bftw_state_init(bftw_state *state, bftw_fn *fn, int nopenfd, int flags, void *ptr) { + state->fn = fn; + state->flags = flags; + state->ptr = ptr; + + state->error = 0; + + dircache_init(&state->cache, nopenfd); + state->current = NULL; + + dirqueue_init(&state->queue); + + dynstr_init(&state->path); +} + +/** + * Set the current path. + */ +static int bftw_set_path(bftw_state *state, const struct dirent *de, const char *name) { + size_t base = 0; + size_t level = 0; + int fd = AT_FDCWD; + + dircache_entry *current = state->current; + if (current) { + base = current->nameoff + current->namelen; + level = current->depth + 1; + fd = dirfd(current->dir); + } + + if (dynstr_concat(&state->path, base, name) != 0) { + return -1; + } + + ftwbuf_init(&state->ftwbuf, base, level); + + if (de) { + ftwbuf_use_dirent(&state->ftwbuf, de); + } + + if ((state->flags & BFTW_STAT) || state->ftwbuf.typeflag == BFTW_UNKNOWN) { + if (ftwbuf_stat(&state->ftwbuf, &state->statbuf, fd, name) != 0) { + state->error = errno; + ftwbuf_set_error(&state->ftwbuf, state->error); } + } + + return 0; +} + +/** internal action: Abort the traversal. */ +#define BFTW_FAIL (-1) - err = errno; - ftwbuf_set_error(&ftwbuf, err); +/** + * Invoke the callback on the given path. + */ +static int bftw_handle_path(bftw_state *state) { + // Never give the callback BFTW_ERROR unless BFTW_RECOVER is specified + if (state->ftwbuf.typeflag == BFTW_ERROR && !(state->flags & BFTW_RECOVER)) { + return BFTW_FAIL; } - switch (fn(path, &ftwbuf, ptr)) { + int action = state->fn(state->path.str, &state->ftwbuf, state->ptr); + switch (action) { + case BFTW_CONTINUE: + case BFTW_SKIP_SIBLINGS: + case BFTW_SKIP_SUBTREE: + case BFTW_STOP: + return action; + + default: + state->error = EINVAL; + return BFTW_FAIL; + } +} + +/** + * Push a new entry onto the queue. + */ +static int bftw_push(bftw_state *state, const char *name) { + dircache_entry *entry = dircache_add(&state->cache, state->current, name); + if (!entry) { + return -1; + } + + return dirqueue_push(&state->queue, entry); +} + +/** + * Pop an entry off the queue. + */ +static void bftw_pop(bftw_state *state) { + dircache_entry_free(&state->cache, state->current); + state->current = dirqueue_pop(&state->queue); +} + +/** + * Dispose of the bftw() state. + */ +static void bftw_state_free(bftw_state *state) { + while (state->current) { + bftw_pop(state); + } + + dynstr_free(&state->path); +} + +int bftw(const char *path, bftw_fn *fn, int nopenfd, int flags, void *ptr) { + int ret = -1; + + bftw_state state; + bftw_state_init(&state, fn, nopenfd, flags, ptr); + + // Handle 'path' itself first + + if (bftw_set_path(&state, NULL, path) != 0) { + goto fail; + } + + switch (bftw_handle_path(&state)) { case BFTW_CONTINUE: case BFTW_SKIP_SIBLINGS: break; @@ -532,38 +657,34 @@ int bftw(const char *path, bftw_fn *fn, int nopenfd, int flags, void *ptr) { case BFTW_STOP: goto done; - default: - err = EINVAL; + case BFTW_FAIL: goto fail; } - if (err != 0 || ftwbuf.typeflag != BFTW_DIR) { + if (state.ftwbuf.typeflag != BFTW_DIR) { goto done; } - current = dircache_add(&cache, NULL, path); - if (!current) { + // Now start the breadth-first search + + state.current = dircache_add(&state.cache, NULL, path); + if (!state.current) { goto fail; } do { - if (dircache_entry_path(current, &dynpath) != 0) { + if (dircache_entry_path(state.current, &state.path) != 0) { goto fail; } - size_t pathlen = dynpath.length; - DIR *dir = dircache_entry_open(&cache, current, dynpath.str); + DIR *dir = dircache_entry_open(&state.cache, state.current, state.path.str); if (!dir) { - if (!(flags & BFTW_RECOVER)) { - goto fail; - } - - err = errno; + state.error = errno; - ftwbuf_init(&ftwbuf, current->nameoff, current->depth); - ftwbuf_set_error(&ftwbuf, err); + ftwbuf_init(&state.ftwbuf, state.current->nameoff, state.current->depth); + ftwbuf_set_error(&state.ftwbuf, state.error); - switch (fn(dynpath.str, &ftwbuf, ptr)) { + switch (bftw_handle_path(&state)) { case BFTW_CONTINUE: case BFTW_SKIP_SIBLINGS: case BFTW_SKIP_SUBTREE: @@ -572,8 +693,7 @@ int bftw(const char *path, bftw_fn *fn, int nopenfd, int flags, void *ptr) { case BFTW_STOP: goto done; - default: - err = EINVAL; + case BFTW_FAIL: goto fail; } } @@ -584,75 +704,50 @@ int bftw(const char *path, bftw_fn *fn, int nopenfd, int flags, void *ptr) { continue; } - if (dynstr_concat(&dynpath, pathlen, de->d_name) != 0) { + if (bftw_set_path(&state, de, de->d_name) != 0) { goto fail; } - ftwbuf_init(&ftwbuf, pathlen, current->depth + 1); - ftwbuf_use_dirent(&ftwbuf, de); - - if ((flags & BFTW_STAT) || ftwbuf.typeflag == BFTW_UNKNOWN) { - if (ftwbuf_stat(&ftwbuf, &sb, dirfd(dir), de->d_name) != 0) { - if (!(flags & BFTW_RECOVER)) { - goto fail; - } - - err = errno; - ftwbuf_set_error(&ftwbuf, err); - } - } - - switch (fn(dynpath.str, &ftwbuf, ptr)) { + switch (bftw_handle_path(&state)) { case BFTW_CONTINUE: - if (ftwbuf.typeflag == BFTW_DIR) { - dircache_entry *next = dircache_add(&cache, current, de->d_name); - if (!next) { - goto fail; - } - - if (dirqueue_push(&queue, next) != 0) { - goto fail; - } - } break; case BFTW_SKIP_SIBLINGS: goto next; case BFTW_SKIP_SUBTREE: - break; + continue; case BFTW_STOP: goto done; - default: - err = EINVAL; + case BFTW_FAIL: goto fail; } + + if (state.ftwbuf.typeflag == BFTW_DIR) { + if (bftw_push(&state, de->d_name) != 0) { + goto fail; + } + } } next: - dircache_entry_free(&cache, current); - current = dirqueue_pop(&queue); - } while (current); + bftw_pop(&state); + } while (state.current); done: - if (err == 0) { + if (state.error == 0) { ret = 0; } fail: - if (err == 0) { - err = errno; - } - - while (current) { - dircache_entry_free(&cache, current); - current = dirqueue_pop(&queue); + if (state.error == 0) { + state.error = errno; } - dynstr_free(&dynpath); + bftw_state_free(&state); - errno = err; + errno = state.error; return ret; } |