libutil: Add a method to the directory iterator to open a sub directory

This is also the reason we need to lug around the original directory
path on Windows.

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

5 files changed, 267 insertions, 20 deletions

diff --git a/bin/gensquashfs/src/fstree_from_dir.c b/bin/gensquashfs/src/fstree_from_dir.c
index 27576ac..85381f9 100644
--- a/bin/gensquashfs/src/fstree_from_dir.c
+++ b/bin/gensquashfs/src/fstree_from_dir.c
@@ -69,15 +69,9 @@ static void discard_node(tree_node_t *root, tree_node_t *n)
 	free(n);
 }
 
-static int scan_dir(fstree_t *fs, tree_node_t *root, const char *path,
+static int scan_dir(fstree_t *fs, tree_node_t *root, dir_iterator_t *dir,
 		    scan_node_callback cb, void *user, unsigned int flags)
 {
-	dir_iterator_t *dir;
-
-	dir = dir_iterator_create(path);
-	if (dir == NULL)
-		return -1;
-
 	for (;;) {
 		dir_entry_t *ent = NULL;
 		tree_node_t *n = NULL;
@@ -87,7 +81,7 @@ static int scan_dir(fstree_t *fs, tree_node_t *root, const char *path,
 		if (ret > 0)
 			break;
 		if (ret < 0)
-			goto fail;
+			return -1;
 
 		if (should_skip(dir, ent, flags)) {
 			free(ent);
@@ -128,7 +122,7 @@ static int scan_dir(fstree_t *fs, tree_node_t *root, const char *path,
 				perror("creating tree node");
 				free(extra);
 				free(ent);
-				goto fail;
+				return -1;
 			}
 
 			ret = (cb == NULL) ? 0 : cb(user, fs, n);
@@ -138,7 +132,7 @@ static int scan_dir(fstree_t *fs, tree_node_t *root, const char *path,
 		free(extra);
 
 		if (ret < 0)
-			goto fail;
+			return -1;
 
 		if (ret > 0) {
 			discard_node(root, n);
@@ -146,18 +140,22 @@ static int scan_dir(fstree_t *fs, tree_node_t *root, const char *path,
 		}
 
 		if (!(flags & DIR_SCAN_NO_RECURSION) && S_ISDIR(n->mode)) {
-			if (fstree_from_subdir(fs, n, path, n->name,
-					       cb, user, flags)) {
-				goto fail;
+			dir_iterator_t *sub;
+
+			ret = dir->open_subdir(dir, &sub);
+			if (ret != 0) {
+				sqfs_perror(n->name, "opening directory", ret);
+				return -1;
 			}
+
+			ret = scan_dir(fs, n, sub, cb, user, flags);
+			sqfs_drop(sub);
+			if (ret)
+				return -1;
 		}
 	}
 
-	sqfs_drop(dir);
 	return 0;
-fail:
-	sqfs_drop(dir);
-	return -1;
 }
 
 int fstree_from_subdir(fstree_t *fs, tree_node_t *root,
@@ -165,6 +163,7 @@ int fstree_from_subdir(fstree_t *fs, tree_node_t *root,
 		       scan_node_callback cb, void *user,
 		       unsigned int flags)
 {
+	dir_iterator_t *dir;
 	size_t plen, slen;
 	char *temp = NULL;
 	int ret;
@@ -195,8 +194,13 @@ int fstree_from_subdir(fstree_t *fs, tree_node_t *root,
 		path = temp;
 	}
 
-	ret = scan_dir(fs, root, path, cb, user, flags);
+	dir = dir_iterator_create(path);
 	free(temp);
+	if (dir == NULL)
+		return -1;
+
+	ret = scan_dir(fs, root, dir, cb, user, flags);
+	sqfs_drop(dir);
 	return ret;
 }
 
diff --git a/include/util/dir_iterator.h b/include/util/dir_iterator.h
index 77849e7..4d7607f 100644
--- a/include/util/dir_iterator.h
+++ b/include/util/dir_iterator.h
@@ -29,6 +29,9 @@ typedef struct dir_iterator_t {
 		    dir_entry_t **out);
 
 	int (*read_link)(struct dir_iterator_t *it, char **out);
+
+	int (*open_subdir)(struct dir_iterator_t *it,
+			   struct dir_iterator_t **out);
 } dir_iterator_t;
 
 dir_iterator_t *dir_iterator_create(const char *path);
diff --git a/lib/util/src/unix_dir_iterator.c b/lib/util/src/unix_dir_iterator.c
index 69a4251..ae878a2 100644
--- a/lib/util/src/unix_dir_iterator.c
+++ b/lib/util/src/unix_dir_iterator.c
@@ -136,6 +136,54 @@ static int dir_next(dir_iterator_t *base, dir_entry_t **out)
 	return it->state;
 }
 
+static int dir_open_subdir(dir_iterator_t *base, dir_iterator_t **out)
+{
+	const unix_dir_iterator_t *it = (const unix_dir_iterator_t *)base;
+	unix_dir_iterator_t *sub = NULL;
+	int fd;
+
+	*out = NULL;
+
+	if (it->state < 0)
+		return it->state;
+
+	if (it->state > 0 || it->ent == NULL)
+		return SQFS_ERROR_NO_ENTRY;
+
+	fd = openat(dirfd(it->dir), it->ent->d_name, O_RDONLY | O_DIRECTORY);
+	if (fd < 0) {
+		if (errno == ENOTDIR)
+			return SQFS_ERROR_NOT_DIR;
+		return SQFS_ERROR_IO;
+	}
+
+	sub = calloc(1, sizeof(*sub));
+	if (sub == NULL)
+		goto fail_alloc;
+
+	sub->dir = fdopendir(fd);
+	if (sub->dir == NULL)
+		goto fail_alloc;
+
+	if (fstat(dirfd(sub->dir), &sub->sb)) {
+		free(sub);
+		return SQFS_ERROR_IO;
+	}
+
+	sqfs_object_init(sub, dir_destroy, NULL);
+	((dir_iterator_t *)sub)->dev = sub->sb.st_dev;
+	((dir_iterator_t *)sub)->next = dir_next;
+	((dir_iterator_t *)sub)->read_link = dir_read_link;
+	((dir_iterator_t *)sub)->open_subdir = dir_open_subdir;
+
+	*out = (dir_iterator_t *)sub;
+	return 0;
+fail_alloc:
+	free(sub);
+	close(fd);
+	return SQFS_ERROR_ALLOC;
+}
+
 dir_iterator_t *dir_iterator_create(const char *path)
 {
 	unix_dir_iterator_t *it = calloc(1, sizeof(*it));
@@ -165,6 +213,7 @@ dir_iterator_t *dir_iterator_create(const char *path)
 	((dir_iterator_t *)it)->dev = it->sb.st_dev;
 	((dir_iterator_t *)it)->next = dir_next;
 	((dir_iterator_t *)it)->read_link = dir_read_link;
+	((dir_iterator_t *)it)->open_subdir = dir_open_subdir;
 
 	return (dir_iterator_t *)it;
 }
diff --git a/lib/util/src/w32_dir_iterator.c b/lib/util/src/w32_dir_iterator.c
index 5400975..f931a26 100644
--- a/lib/util/src/w32_dir_iterator.c
+++ b/lib/util/src/w32_dir_iterator.c
@@ -107,6 +107,51 @@ static void dir_iterator_destroy(sqfs_object_t *obj)
 	free(dir);
 }
 
+static int dir_iterator_open_subdir(dir_iterator_t *it, dir_iterator_t **out)
+{
+	const dir_iterator_win32_t *dir = (const dir_iterator_win32_t *)it;
+	dir_iterator_win32_t *sub = NULL;
+	size_t plen, slen, total;
+
+	*out = NULL;
+
+	if (dir->state != 0)
+		return (dir->state > 0) ? SQFS_ERROR_NO_ENTRY : dir->state;
+
+	if (!(dir->ent.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
+		return SQFS_ERROR_NOT_DIR;
+
+	plen = wcslen(dir->path) - 1;
+	slen = wcslen(dir->ent.cFileName);
+	total = plen + slen + 3;
+
+	sub = alloc_flex(sizeof(*sub), sizeof(WCHAR), total);
+	if (sub == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	memcpy(sub->path, dir->path, plen * sizeof(WCHAR));
+	memcpy(sub->path + plen, dir->ent.cFileName, slen * sizeof(WCHAR));
+	sub->path[plen + slen    ] = '\\';
+	sub->path[plen + slen + 1] = '*';
+	sub->path[plen + slen + 2] = '\0';
+
+	sqfs_object_init(sub, dir_iterator_destroy, NULL);
+	((dir_iterator_t *)sub)->next = dir_iterator_next;
+	((dir_iterator_t *)sub)->read_link = dir_iterator_read_link;
+	((dir_iterator_t *)sub)->open_subdir = dir_iterator_open_subdir;
+	sub->is_first = true;
+	sub->state = 0;
+
+	sub->dirhnd = FindFirstFileW(sub->path, &sub->ent);
+	if (sub->dirhnd == INVALID_HANDLE_VALUE) {
+		free(sub);
+		return SQFS_ERROR_IO;
+	}
+
+	*out = (dir_iterator_t *)sub;
+	return 0;
+}
+
 dir_iterator_t *dir_iterator_create(const char *path)
 {
 	dir_iterator_win32_t *it;
@@ -152,6 +197,7 @@ dir_iterator_t *dir_iterator_create(const char *path)
 
 	((dir_iterator_t *)it)->next = dir_iterator_next;
 	((dir_iterator_t *)it)->read_link = dir_iterator_read_link;
+	((dir_iterator_t *)it)->open_subdir = dir_iterator_open_subdir;
 	it->is_first = true;
 	it->state = 0;
 
diff --git a/lib/util/test/dir_iterator.c b/lib/util/test/dir_iterator.c
index 22b05dc..d209afd 100644
--- a/lib/util/test/dir_iterator.c
+++ b/lib/util/test/dir_iterator.c
@@ -7,6 +7,7 @@
 #include "config.h"
 
 #include "util/dir_iterator.h"
+#include "sqfs/error.h"
 #include "util/test.h"
 #include "compat.h"
 
@@ -20,8 +21,8 @@ static int compare_entries(const void *a, const void *b)
 
 int main(int argc, char **argv)
 {
-	dir_iterator_t *dir;
-	dir_entry_t *ent[6];
+	dir_iterator_t *dir, *suba, *subb, *subc, *sub;
+	dir_entry_t *dent, *ent[6];
 	size_t i;
 	int ret;
 	(void)argc; (void)argv;
@@ -210,5 +211,149 @@ int main(int argc, char **argv)
 	for (i = 0; i < 5; ++i)
 		free(ent[i]);
 
+	/* test sub directory iterators */
+	suba = NULL;
+	subb = NULL;
+	subc = NULL;
+
+	dir = dir_iterator_create(TEST_PATH);
+	TEST_NOT_NULL(dir);
+
+	for (i = 0; i < 5; ++i) {
+		ret = dir->next(dir, &dent);
+		TEST_NOT_NULL(dent);
+		TEST_EQUAL_I(ret, 0);
+
+		if (!strcmp(dent->name, "dira")) {
+			TEST_NULL(suba);
+			ret = dir->open_subdir(dir, &suba);
+			TEST_NOT_NULL(suba);
+			TEST_EQUAL_I(ret, 0);
+		} else if (!strcmp(dent->name, "dirb")) {
+			TEST_NULL(subb);
+			ret = dir->open_subdir(dir, &subb);
+			TEST_NOT_NULL(subb);
+			TEST_EQUAL_I(ret, 0);
+		} else if (!strcmp(dent->name, "dirc")) {
+			TEST_NULL(subc);
+			ret = dir->open_subdir(dir, &subc);
+			TEST_NOT_NULL(subc);
+			TEST_EQUAL_I(ret, 0);
+		}
+
+		free(dent);
+	}
+
+	ret = dir->next(dir, &dent);
+	TEST_NULL(dent);
+	TEST_ASSERT(ret > 0);
+	dir = sqfs_drop(dir);
+
+	TEST_NOT_NULL(suba);
+	TEST_NOT_NULL(subb);
+	TEST_NOT_NULL(subc);
+
+	/* sub iterator a */
+	for (i = 0; i < 5; ++i) {
+		ret = suba->next(suba, &ent[i]);
+		TEST_NOT_NULL(ent[0]);
+		TEST_EQUAL_I(ret, 0);
+
+		if (S_ISREG(ent[i]->mode)) {
+			ret = suba->open_subdir(suba, &sub);
+			TEST_NULL(sub);
+			TEST_EQUAL_I(ret, SQFS_ERROR_NOT_DIR);
+		}
+	}
+
+	ret = suba->next(suba, &dent);
+	TEST_NULL(dent);
+	TEST_ASSERT(ret > 0);
+	suba = sqfs_drop(suba);
+
+	qsort(ent, 5, sizeof(ent[0]), compare_entries);
+
+	TEST_STR_EQUAL(ent[0]->name, ".");
+	TEST_ASSERT(S_ISDIR(ent[0]->mode));
+	TEST_STR_EQUAL(ent[1]->name, "..");
+	TEST_ASSERT(S_ISDIR(ent[1]->mode));
+	TEST_STR_EQUAL(ent[2]->name, "file_a0");
+	TEST_ASSERT(S_ISREG(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "file_a1");
+	TEST_ASSERT(S_ISREG(ent[3]->mode));
+	TEST_STR_EQUAL(ent[4]->name, "file_a2");
+	TEST_ASSERT(S_ISREG(ent[4]->mode));
+
+	for (i = 0; i < 5; ++i)
+		free(ent[i]);
+
+	/* sub iterator b */
+	for (i = 0; i < 5; ++i) {
+		ret = subb->next(subb, &ent[i]);
+		TEST_NOT_NULL(ent[0]);
+		TEST_EQUAL_I(ret, 0);
+
+		if (S_ISREG(ent[i]->mode)) {
+			ret = subb->open_subdir(subb, &sub);
+			TEST_NULL(sub);
+			TEST_EQUAL_I(ret, SQFS_ERROR_NOT_DIR);
+		}
+	}
+
+	ret = subb->next(subb, &dent);
+	TEST_NULL(dent);
+	TEST_ASSERT(ret > 0);
+	subb = sqfs_drop(subb);
+
+	qsort(ent, 5, sizeof(ent[0]), compare_entries);
+
+	TEST_STR_EQUAL(ent[0]->name, ".");
+	TEST_ASSERT(S_ISDIR(ent[0]->mode));
+	TEST_STR_EQUAL(ent[1]->name, "..");
+	TEST_ASSERT(S_ISDIR(ent[1]->mode));
+	TEST_STR_EQUAL(ent[2]->name, "file_b0");
+	TEST_ASSERT(S_ISREG(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "file_b1");
+	TEST_ASSERT(S_ISREG(ent[3]->mode));
+	TEST_STR_EQUAL(ent[4]->name, "file_b2");
+	TEST_ASSERT(S_ISREG(ent[4]->mode));
+
+	for (i = 0; i < 5; ++i)
+		free(ent[i]);
+
+	/* sub iterator c */
+	for (i = 0; i < 5; ++i) {
+		ret = subc->next(subc, &ent[i]);
+		TEST_NOT_NULL(ent[0]);
+		TEST_EQUAL_I(ret, 0);
+
+		if (S_ISREG(ent[i]->mode)) {
+			ret = subc->open_subdir(subc, &sub);
+			TEST_NULL(sub);
+			TEST_EQUAL_I(ret, SQFS_ERROR_NOT_DIR);
+		}
+	}
+
+	ret = subc->next(subc, &dent);
+	TEST_NULL(dent);
+	TEST_ASSERT(ret > 0);
+	subc = sqfs_drop(subc);
+
+	qsort(ent, 5, sizeof(ent[0]), compare_entries);
+
+	TEST_STR_EQUAL(ent[0]->name, ".");
+	TEST_ASSERT(S_ISDIR(ent[0]->mode));
+	TEST_STR_EQUAL(ent[1]->name, "..");
+	TEST_ASSERT(S_ISDIR(ent[1]->mode));
+	TEST_STR_EQUAL(ent[2]->name, "file_c0");
+	TEST_ASSERT(S_ISREG(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "file_c1");
+	TEST_ASSERT(S_ISREG(ent[3]->mode));
+	TEST_STR_EQUAL(ent[4]->name, "file_c2");
+	TEST_ASSERT(S_ISREG(ent[4]->mode));
+
+	for (i = 0; i < 5; ++i)
+		free(ent[i]);
+
 	return EXIT_SUCCESS;
 }