git

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#include "git-compat-util.h"
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#include "dir.h"
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#include "iterator.h"
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#include "dir-iterator.h"
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#include "string-list.h"
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struct dir_iterator_level {
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	DIR *dir;
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	/*
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	 * The directory entries of the current level. This list will only be
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	 * populated when the iterator is ordered. In that case, `dir` will be
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	 * set to `NULL`.
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	 */
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	struct string_list entries;
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	size_t entries_idx;
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	/*
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	 * The length of the directory part of path at this level
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	 * (including a trailing '/'):
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	 */
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	size_t prefix_len;
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};
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/*
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 * The full data structure used to manage the internal directory
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 * iteration state. It includes members that are not part of the
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 * public interface.
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 */
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struct dir_iterator_int {
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	struct dir_iterator base;
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	/*
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	 * The number of levels currently on the stack. After the first
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	 * call to dir_iterator_begin(), if it succeeds to open the
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	 * first level's dir, this will always be at least 1. Then,
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	 * when it comes to zero the iteration is ended and this
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	 * struct is freed.
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	 */
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	size_t levels_nr;
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	/* The number of levels that have been allocated on the stack */
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	size_t levels_alloc;
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	/*
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	 * A stack of levels. levels[0] is the uppermost directory
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	 * that will be included in this iteration.
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	 */
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	struct dir_iterator_level *levels;
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	/* Combination of flags for this dir-iterator */
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	unsigned int flags;
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};
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static int next_directory_entry(DIR *dir, const char *path,
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				struct dirent **out)
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{
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	struct dirent *de;
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repeat:
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	errno = 0;
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	de = readdir(dir);
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	if (!de) {
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		if (errno) {
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			warning_errno("error reading directory '%s'",
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				      path);
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			return -1;
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		}
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		return 1;
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	}
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	if (is_dot_or_dotdot(de->d_name))
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		goto repeat;
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	*out = de;
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	return 0;
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}
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/*
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 * Push a level in the iter stack and initialize it with information from
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 * the directory pointed by iter->base->path. It is assumed that this
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 * strbuf points to a valid directory path. Return 0 on success and -1
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 * otherwise, setting errno accordingly and leaving the stack unchanged.
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 */
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static int push_level(struct dir_iterator_int *iter)
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{
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	struct dir_iterator_level *level;
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	ALLOC_GROW(iter->levels, iter->levels_nr + 1, iter->levels_alloc);
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	level = &iter->levels[iter->levels_nr++];
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	if (!is_dir_sep(iter->base.path.buf[iter->base.path.len - 1]))
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		strbuf_addch(&iter->base.path, '/');
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	level->prefix_len = iter->base.path.len;
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	level->dir = opendir(iter->base.path.buf);
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	if (!level->dir) {
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		int saved_errno = errno;
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		if (errno != ENOENT) {
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			warning_errno("error opening directory '%s'",
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				      iter->base.path.buf);
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		}
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		iter->levels_nr--;
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		errno = saved_errno;
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		return -1;
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	}
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	string_list_init_dup(&level->entries);
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	level->entries_idx = 0;
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	/*
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	 * When the iterator is sorted we read and sort all directory entries
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	 * directly.
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	 */
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	if (iter->flags & DIR_ITERATOR_SORTED) {
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		struct dirent *de;
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		while (1) {
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			int ret = next_directory_entry(level->dir, iter->base.path.buf, &de);
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			if (ret < 0) {
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				if (errno != ENOENT &&
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				    iter->flags & DIR_ITERATOR_PEDANTIC)
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					return -1;
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				continue;
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			} else if (ret > 0) {
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				break;
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			}
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			string_list_append(&level->entries, de->d_name);
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		}
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		string_list_sort(&level->entries);
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		closedir(level->dir);
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		level->dir = NULL;
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	}
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	return 0;
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}
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/*
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 * Pop the top level on the iter stack, releasing any resources associated
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 * with it. Return the new value of iter->levels_nr.
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 */
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static int pop_level(struct dir_iterator_int *iter)
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{
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	struct dir_iterator_level *level =
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		&iter->levels[iter->levels_nr - 1];
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	if (level->dir && closedir(level->dir))
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		warning_errno("error closing directory '%s'",
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			      iter->base.path.buf);
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	level->dir = NULL;
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	string_list_clear(&level->entries, 0);
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	return --iter->levels_nr;
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}
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/*
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 * Populate iter->base with the necessary information on the next iteration
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 * entry, represented by the given name. Return 0 on success and -1
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 * otherwise, setting errno accordingly.
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 */
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static int prepare_next_entry_data(struct dir_iterator_int *iter,
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				   const char *name)
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{
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	int err, saved_errno;
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	strbuf_addstr(&iter->base.path, name);
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	/*
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	 * We have to reset these because the path strbuf might have
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	 * been realloc()ed at the previous strbuf_addstr().
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	 */
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	iter->base.relative_path = iter->base.path.buf +
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				   iter->levels[0].prefix_len;
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	iter->base.basename = iter->base.path.buf +
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			      iter->levels[iter->levels_nr - 1].prefix_len;
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	err = lstat(iter->base.path.buf, &iter->base.st);
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	saved_errno = errno;
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	if (err && errno != ENOENT)
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		warning_errno("failed to stat '%s'", iter->base.path.buf);
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	errno = saved_errno;
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	return err;
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}
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int dir_iterator_advance(struct dir_iterator *dir_iterator)
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{
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	struct dir_iterator_int *iter =
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		(struct dir_iterator_int *)dir_iterator;
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	if (S_ISDIR(iter->base.st.st_mode) && push_level(iter)) {
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		if (errno != ENOENT && iter->flags & DIR_ITERATOR_PEDANTIC)
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			goto error_out;
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		if (iter->levels_nr == 0)
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			goto error_out;
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	}
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	/* Loop until we find an entry that we can give back to the caller. */
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	while (1) {
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		struct dirent *de;
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		struct dir_iterator_level *level =
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			&iter->levels[iter->levels_nr - 1];
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		const char *name;
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		strbuf_setlen(&iter->base.path, level->prefix_len);
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		if (level->dir) {
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			int ret = next_directory_entry(level->dir, iter->base.path.buf, &de);
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			if (ret < 0) {
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				if (iter->flags & DIR_ITERATOR_PEDANTIC)
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					goto error_out;
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				continue;
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			} else if (ret > 0) {
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				if (pop_level(iter) == 0)
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					return dir_iterator_abort(dir_iterator);
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				continue;
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			}
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			name = de->d_name;
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		} else {
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			if (level->entries_idx >= level->entries.nr) {
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				if (pop_level(iter) == 0)
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					return dir_iterator_abort(dir_iterator);
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				continue;
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			}
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			name = level->entries.items[level->entries_idx++].string;
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		}
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		if (prepare_next_entry_data(iter, name)) {
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			if (errno != ENOENT && iter->flags & DIR_ITERATOR_PEDANTIC)
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				goto error_out;
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			continue;
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		}
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		return ITER_OK;
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	}
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error_out:
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	dir_iterator_abort(dir_iterator);
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	return ITER_ERROR;
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}
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int dir_iterator_abort(struct dir_iterator *dir_iterator)
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{
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	struct dir_iterator_int *iter = (struct dir_iterator_int *)dir_iterator;
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	for (; iter->levels_nr; iter->levels_nr--) {
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		struct dir_iterator_level *level =
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			&iter->levels[iter->levels_nr - 1];
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		if (level->dir && closedir(level->dir)) {
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			int saved_errno = errno;
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			strbuf_setlen(&iter->base.path, level->prefix_len);
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			errno = saved_errno;
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			warning_errno("error closing directory '%s'",
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				      iter->base.path.buf);
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		}
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		string_list_clear(&level->entries, 0);
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	}
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	free(iter->levels);
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	strbuf_release(&iter->base.path);
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	free(iter);
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	return ITER_DONE;
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}
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struct dir_iterator *dir_iterator_begin(const char *path, unsigned int flags)
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{
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	struct dir_iterator_int *iter = xcalloc(1, sizeof(*iter));
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	struct dir_iterator *dir_iterator = &iter->base;
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	int saved_errno, err;
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	strbuf_init(&iter->base.path, PATH_MAX);
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	strbuf_addstr(&iter->base.path, path);
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	ALLOC_GROW(iter->levels, 10, iter->levels_alloc);
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	iter->levels_nr = 0;
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	iter->flags = flags;
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	/*
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	 * Note: lstat already checks for NULL or empty strings and
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	 * nonexistent paths.
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	 */
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	err = lstat(iter->base.path.buf, &iter->base.st);
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291
	if (err < 0) {
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		saved_errno = errno;
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		goto error_out;
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	}
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	if (!S_ISDIR(iter->base.st.st_mode)) {
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		saved_errno = ENOTDIR;
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		goto error_out;
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	}
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301
	return dir_iterator;
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error_out:
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	dir_iterator_abort(dir_iterator);
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	errno = saved_errno;
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	return NULL;
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}
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