diff options
Diffstat (limited to 'third_party/git/dir-iterator.c')
| -rw-r--r-- | third_party/git/dir-iterator.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/third_party/git/dir-iterator.c b/third_party/git/dir-iterator.c new file mode 100644 index 000000000000..b17e9f970a74 --- /dev/null +++ b/third_party/git/dir-iterator.c @@ -0,0 +1,235 @@ +#include "cache.h" +#include "dir.h" +#include "iterator.h" +#include "dir-iterator.h" + +struct dir_iterator_level { + DIR *dir; + + /* + * The length of the directory part of path at this level + * (including a trailing '/'): + */ + size_t prefix_len; +}; + +/* + * The full data structure used to manage the internal directory + * iteration state. It includes members that are not part of the + * public interface. + */ +struct dir_iterator_int { + struct dir_iterator base; + + /* + * The number of levels currently on the stack. After the first + * call to dir_iterator_begin(), if it succeeds to open the + * first level's dir, this will always be at least 1. Then, + * when it comes to zero the iteration is ended and this + * struct is freed. + */ + size_t levels_nr; + + /* The number of levels that have been allocated on the stack */ + size_t levels_alloc; + + /* + * A stack of levels. levels[0] is the uppermost directory + * that will be included in this iteration. + */ + struct dir_iterator_level *levels; + + /* Combination of flags for this dir-iterator */ + unsigned int flags; +}; + +/* + * Push a level in the iter stack and initialize it with information from + * the directory pointed by iter->base->path. It is assumed that this + * strbuf points to a valid directory path. Return 0 on success and -1 + * otherwise, setting errno accordingly and leaving the stack unchanged. + */ +static int push_level(struct dir_iterator_int *iter) +{ + struct dir_iterator_level *level; + + ALLOC_GROW(iter->levels, iter->levels_nr + 1, iter->levels_alloc); + level = &iter->levels[iter->levels_nr++]; + + if (!is_dir_sep(iter->base.path.buf[iter->base.path.len - 1])) + strbuf_addch(&iter->base.path, '/'); + level->prefix_len = iter->base.path.len; + + level->dir = opendir(iter->base.path.buf); + if (!level->dir) { + int saved_errno = errno; + if (errno != ENOENT) { + warning_errno("error opening directory '%s'", + iter->base.path.buf); + } + iter->levels_nr--; + errno = saved_errno; + return -1; + } + + return 0; +} + +/* + * Pop the top level on the iter stack, releasing any resources associated + * with it. Return the new value of iter->levels_nr. + */ +static int pop_level(struct dir_iterator_int *iter) +{ + struct dir_iterator_level *level = + &iter->levels[iter->levels_nr - 1]; + + if (level->dir && closedir(level->dir)) + warning_errno("error closing directory '%s'", + iter->base.path.buf); + level->dir = NULL; + + return --iter->levels_nr; +} + +/* + * Populate iter->base with the necessary information on the next iteration + * entry, represented by the given dirent de. Return 0 on success and -1 + * otherwise, setting errno accordingly. + */ +static int prepare_next_entry_data(struct dir_iterator_int *iter, + struct dirent *de) +{ + int err, saved_errno; + + strbuf_addstr(&iter->base.path, de->d_name); + /* + * We have to reset these because the path strbuf might have + * been realloc()ed at the previous strbuf_addstr(). + */ + iter->base.relative_path = iter->base.path.buf + + iter->levels[0].prefix_len; + iter->base.basename = iter->base.path.buf + + iter->levels[iter->levels_nr - 1].prefix_len; + + if (iter->flags & DIR_ITERATOR_FOLLOW_SYMLINKS) + err = stat(iter->base.path.buf, &iter->base.st); + else + err = lstat(iter->base.path.buf, &iter->base.st); + + saved_errno = errno; + if (err && errno != ENOENT) + warning_errno("failed to stat '%s'", iter->base.path.buf); + + errno = saved_errno; + return err; +} + +int dir_iterator_advance(struct dir_iterator *dir_iterator) +{ + struct dir_iterator_int *iter = + (struct dir_iterator_int *)dir_iterator; + + if (S_ISDIR(iter->base.st.st_mode) && push_level(iter)) { + if (errno != ENOENT && iter->flags & DIR_ITERATOR_PEDANTIC) + goto error_out; + if (iter->levels_nr == 0) + goto error_out; + } + + /* Loop until we find an entry that we can give back to the caller. */ + while (1) { + struct dirent *de; + struct dir_iterator_level *level = + &iter->levels[iter->levels_nr - 1]; + + strbuf_setlen(&iter->base.path, level->prefix_len); + errno = 0; + de = readdir(level->dir); + + if (!de) { + if (errno) { + warning_errno("error reading directory '%s'", + iter->base.path.buf); + if (iter->flags & DIR_ITERATOR_PEDANTIC) + goto error_out; + } else if (pop_level(iter) == 0) { + return dir_iterator_abort(dir_iterator); + } + continue; + } + + if (is_dot_or_dotdot(de->d_name)) + continue; + + if (prepare_next_entry_data(iter, de)) { + if (errno != ENOENT && iter->flags & DIR_ITERATOR_PEDANTIC) + goto error_out; + continue; + } + + return ITER_OK; + } + +error_out: + dir_iterator_abort(dir_iterator); + return ITER_ERROR; +} + +int dir_iterator_abort(struct dir_iterator *dir_iterator) +{ + struct dir_iterator_int *iter = (struct dir_iterator_int *)dir_iterator; + + for (; iter->levels_nr; iter->levels_nr--) { + struct dir_iterator_level *level = + &iter->levels[iter->levels_nr - 1]; + + if (level->dir && closedir(level->dir)) { + int saved_errno = errno; + strbuf_setlen(&iter->base.path, level->prefix_len); + errno = saved_errno; + warning_errno("error closing directory '%s'", + iter->base.path.buf); + } + } + + free(iter->levels); + strbuf_release(&iter->base.path); + free(iter); + return ITER_DONE; +} + +struct dir_iterator *dir_iterator_begin(const char *path, unsigned int flags) +{ + struct dir_iterator_int *iter = xcalloc(1, sizeof(*iter)); + struct dir_iterator *dir_iterator = &iter->base; + int saved_errno; + + strbuf_init(&iter->base.path, PATH_MAX); + strbuf_addstr(&iter->base.path, path); + + ALLOC_GROW(iter->levels, 10, iter->levels_alloc); + iter->levels_nr = 0; + iter->flags = flags; + + /* + * Note: stat already checks for NULL or empty strings and + * inexistent paths. + */ + if (stat(iter->base.path.buf, &iter->base.st) < 0) { + saved_errno = errno; + goto error_out; + } + + if (!S_ISDIR(iter->base.st.st_mode)) { + saved_errno = ENOTDIR; + goto error_out; + } + + return dir_iterator; + +error_out: + dir_iterator_abort(dir_iterator); + errno = saved_errno; + return NULL; +} |