Split recursive directory iterator

The recursive part and the filter part are split up, the recursive
iterator wrapper is moved into libsquashfs and the libio iterator
is modified to use that internally instead of implementig the
recursion step.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 40 insertions, 131 deletions

diff --git a/lib/io/src/dir_tree_iterator.c b/lib/io/src/dir_tree_iterator.c
index 0ec478c..3c25529 100644
--- a/lib/io/src/dir_tree_iterator.c
+++ b/lib/io/src/dir_tree_iterator.c
@@ -13,53 +13,18 @@
 #include <stdlib.h>
 #include <string.h>
 
-typedef struct dir_stack_t {
-	struct dir_stack_t *next;
-	sqfs_dir_iterator_t *dir;
-	char name[];
-} dir_stack_t;
-
 typedef struct {
 	sqfs_dir_iterator_t base;
 
 	dir_tree_cfg_t cfg;
 	int state;
-	dir_stack_t *top;
+	sqfs_dir_iterator_t *rec;
 } dir_tree_iterator_t;
 
-static void pop(dir_tree_iterator_t *it)
-{
-	if (it->top != NULL) {
-		dir_stack_t *ent = it->top;
-		it->top = it->top->next;
-
-		sqfs_drop(ent->dir);
-		free(ent);
-	}
-}
-
-static int push(dir_tree_iterator_t *it, const char *name,
-		sqfs_dir_iterator_t *dir)
-{
-	dir_stack_t *ent = alloc_flex(sizeof(*ent), 1, strlen(name) + 1);
-
-	if (ent == NULL)
-		return SQFS_ERROR_ALLOC;
-
-	strcpy(ent->name, name);
-	ent->dir = sqfs_grab(dir);
-	ent->next = it->top;
-	it->top = ent;
-	return 0;
-}
-
 static bool should_skip(const dir_tree_iterator_t *dir, const sqfs_dir_entry_t *ent)
 {
 	unsigned int type_mask;
 
-	if (!strcmp(ent->name, ".") || !strcmp(ent->name, ".."))
-		return true;
-
 	if ((dir->cfg.flags & DIR_SCAN_ONE_FILESYSTEM)) {
 		if (ent->flags & SQFS_DIR_ENTRY_FLAG_MOUNT_POINT)
 			return true;
@@ -80,20 +45,11 @@ static bool should_skip(const dir_tree_iterator_t *dir, const sqfs_dir_entry_t *
 
 static sqfs_dir_entry_t *expand_path(const dir_tree_iterator_t *it, sqfs_dir_entry_t *ent)
 {
-	size_t slen = strlen(ent->name) + 1, plen = 0;
-	dir_stack_t *sit;
-	char *dst;
-
-	for (sit = it->top; sit != NULL; sit = sit->next) {
-		if (sit->name[0] != '\0')
-			plen += strlen(sit->name) + 1;
-	}
-
-	if (it->cfg.prefix != NULL && it->cfg.prefix[0] != '\0')
-		plen += strlen(it->cfg.prefix) + 1;
-
-	if (plen > 0) {
+	if (it->cfg.prefix != NULL && it->cfg.prefix[0] != '\0') {
+		size_t plen = strlen(it->cfg.prefix) + 1;
+		size_t slen = strlen(ent->name) + 1;
 		void *new = realloc(ent, sizeof(*ent) + plen + slen);
+
 		if (new == NULL) {
 			free(ent);
 			return NULL;
@@ -101,22 +57,9 @@ static sqfs_dir_entry_t *expand_path(const dir_tree_iterator_t *it, sqfs_dir_ent
 
 		ent = new;
 		memmove(ent->name + plen, ent->name, slen);
-		dst = ent->name + plen;
-
-		for (sit = it->top; sit != NULL; sit = sit->next) {
-			size_t len = strlen(sit->name);
-			if (len > 0) {
-				*(--dst) = '/';
-				dst -= len;
-				memcpy(dst, sit->name, len);
-			}
-		}
 
-		if (it->cfg.prefix != NULL && it->cfg.prefix[0] != '\0') {
-			size_t len = strlen(it->cfg.prefix);
-			memcpy(ent->name, it->cfg.prefix, len);
-			ent->name[len] = '/';
-		}
+		memcpy(ent->name, it->cfg.prefix, plen - 1);
+		ent->name[plen - 1] = '/';
 	}
 
 	return ent;
@@ -145,48 +88,36 @@ static void destroy(sqfs_object_t *obj)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)obj;
 
-	while (it->top != NULL)
-		pop(it);
-
+	sqfs_drop(it->rec);
 	free(it);
 }
 
 static int next(sqfs_dir_iterator_t *base, sqfs_dir_entry_t **out)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)base;
-	sqfs_dir_iterator_t *sub;
 	sqfs_dir_entry_t *ent;
 	int ret;
+
+	if (it->state)
+		return it->state;
 retry:
 	*out = NULL;
-	sub = NULL;
 	ent = NULL;
 
-	if (it->state != 0)
-		return it->state;
-
 	for (;;) {
-		if (it->top == NULL) {
-			ret = 1;
-			goto fail;
-		}
-
-		ret = it->top->dir->next(it->top->dir, &ent);
-		if (ret < 0)
-			goto fail;
-
-		if (ret > 0) {
-			pop(it);
-			continue;
+		ret = it->rec->next(it->rec, &ent);
+		if (ret != 0) {
+			it->state = ret;
+			return ret;
 		}
 
-		if (should_skip(it, ent)) {
-			free(ent);
-			ent = NULL;
-			continue;
-		}
+		if (!should_skip(it, ent))
+			break;
 
-		break;
+		if (S_ISDIR(ent->mode))
+			it->rec->ignore_subdir(it->rec);
+		free(ent);
+		ent = NULL;
 	}
 
 	ent = expand_path(it, ent);
@@ -198,19 +129,8 @@ retry:
 	apply_changes(it, ent);
 
 	if (S_ISDIR(ent->mode)) {
-		if (!(it->cfg.flags & DIR_SCAN_NO_RECURSION)) {
-			const char *name = strrchr(ent->name, '/');
-			name = (name == NULL) ? ent->name : (name + 1);
-
-			ret = it->top->dir->open_subdir(it->top->dir, &sub);
-			if (ret != 0)
-				goto fail;
-
-			ret = push(it, name, sub);
-			sqfs_drop(sub);
-			if (ret != 0)
-				goto fail;
-		}
+		if (it->cfg.flags & DIR_SCAN_NO_RECURSION)
+			it->rec->ignore_subdir(it->rec);
 
 		if (it->cfg.flags & DIR_SCAN_NO_DIR) {
 			free(ent);
@@ -237,65 +157,54 @@ retry:
 
 	*out = ent;
 	return it->state;
-fail:
-	free(ent);
-	it->state = ret;
-	return it->state;
 }
 
 static int read_link(sqfs_dir_iterator_t *base, char **out)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)base;
 
-	if (it->top == NULL) {
-		*out = NULL;
-		return SQFS_ERROR_NO_ENTRY;
-	}
+	if (it->state)
+		return it->state;
 
-	return it->top->dir->read_link(it->top->dir, out);
+	return it->rec->read_link(it->rec, out);
 }
 
 static int open_subdir(sqfs_dir_iterator_t *base, sqfs_dir_iterator_t **out)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)base;
 
-	if (it->top == NULL) {
-		*out = NULL;
-		return SQFS_ERROR_NO_ENTRY;
-	}
+	if (it->state)
+		return it->state;
 
-	return it->top->dir->open_subdir(it->top->dir, out);
+	return it->rec->open_subdir(it->rec, out);
 }
 
 static void ignore_subdir(sqfs_dir_iterator_t *base)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)base;
 
-	pop(it);
+	if (it->state == 0)
+		it->rec->ignore_subdir(it->rec);
 }
 
 static int open_file_ro(sqfs_dir_iterator_t *base, sqfs_istream_t **out)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)base;
 
-	if (it->top == NULL) {
-		*out = NULL;
-		return SQFS_ERROR_NO_ENTRY;
-	}
+	if (it->state)
+		return it->state;
 
-	return it->top->dir->open_file_ro(it->top->dir, out);
+	return it->rec->open_file_ro(it->rec, out);
 }
 
 static int read_xattr(sqfs_dir_iterator_t *base, sqfs_xattr_t **out)
 {
 	dir_tree_iterator_t *it = (dir_tree_iterator_t *)base;
 
-	if (it->top == NULL) {
-		*out = NULL;
-		return SQFS_ERROR_NO_ENTRY;
-	}
+	if (it->state)
+		return it->state;
 
-	return it->top->dir->read_xattr(it->top->dir, out);
+	return it->rec->read_xattr(it->rec, out);
 }
 
 sqfs_dir_iterator_t *dir_tree_iterator_create(const char *path,
@@ -318,9 +227,9 @@ sqfs_dir_iterator_t *dir_tree_iterator_create(const char *path,
 		goto fail;
 	}
 
-	ret = push(it, "", dir);
-	dir = sqfs_drop(dir);
-	if (ret != 0) {
+	ret = sqfs_dir_iterator_create_recursive(&it->rec, dir);
+	sqfs_drop(dir);
+	if (ret) {
 		fprintf(stderr, "%s: out of memory\n", path);
 		goto fail;
 	}