directory_iterator: return bool instead of int

This commit changes the return type of sqsh_directory_iterator_next()
from int to bool. The return value is now used to indicate whether
there is more data to read from the directory iterator. The error code
is now stored in a pointer to an int instead of being returned directly.

examples/list_dir_ll.c

@@ -50,7 +50,7 @@ main(int argc, char *argv[]) {
 		return 1;
 	}
 
-	while ((error_code = sqsh_directory_iterator_next(iterator)) > 0) {
+	while (sqsh_directory_iterator_next(iterator, &error_code)) {
 		const char *name = sqsh_directory_iterator_name(iterator);
 		size_t size = sqsh_directory_iterator_name_size(iterator);
 		fwrite(name, size, 1, stdout);

fuzzer/simple.c

@@ -95,7 +95,7 @@ LLVMFuzzerTestOneInput(char *data, size_t size) {
 	if (iter == NULL) {
 		goto out;
 	}
-	while ((rv = sqsh_directory_iterator_next(iter)) > 0) {
+	while (sqsh_directory_iterator_next(iter, &rv)) {
 		if (read_file(iter) < 0)
 			break;
 	}

include/sqsh_directory.h

@@ -63,12 +63,14 @@ sqsh_directory_iterator_new(struct SqshFile *file, int *err);
  * @brief Advances the iterator to the next entry.
  *
  * @param[in,out] iterator The iterator to advance.
+ * @param[out]    err      Pointer to an int where the error code will be
+ * stored.
  *
- * @return amount of bytes available in the current block on success, 0 if the
- * end of the directory has been reached, a negative value on error.
+ * @retval true if the iterator has been advanced
+ * @retval false if the iterator has reached the end of the directory
  */
-SQSH_NO_UNUSED int
-sqsh_directory_iterator_next(struct SqshDirectoryIterator *iterator);
+SQSH_NO_UNUSED bool
+sqsh_directory_iterator_next(struct SqshDirectoryIterator *iterator, int *err);
 
 /**
  * @memberof SqshDirectoryIterator

lib/directory/directory_iterator.c

@@ -158,7 +158,7 @@ sqsh_directory_iterator_lookup(
 		}
 	}
 
-	while (sqsh_directory_iterator_next(iterator) > 0) {
+	while (sqsh_directory_iterator_next(iterator, &rv) > 0) {
 		const size_t entry_name_size =
 				sqsh_directory_iterator_name_size(iterator);
 		const char *entry_name = sqsh_directory_iterator_name(iterator);
@@ -170,7 +170,11 @@ sqsh_directory_iterator_lookup(
 		}
 	}
 
-	return -SQSH_ERROR_NO_SUCH_FILE;
+	if (rv < 0) {
+		return rv;
+	} else {
+		return -SQSH_ERROR_NO_SUCH_FILE;
+	}
 }
 
 int
@@ -301,18 +305,19 @@ process_fragment(struct SqshDirectoryIterator *iterator) {
 	return rv;
 }
 
-int
-sqsh_directory_iterator_next(struct SqshDirectoryIterator *iterator) {
+bool
+sqsh_directory_iterator_next(struct SqshDirectoryIterator *iterator, int *err) {
 	int rv = 0;
 	size_t size;
+	bool has_next = false;
 
 	if (iterator->remaining_size == 0) {
-		return 0;
+		goto out;
 	} else if (iterator->remaining_entries == 0) {
 		/*  New fragment begins */
 		rv = process_fragment(iterator);
 		if (rv < 0) {
-			return rv;
+			goto out;
 		}
 	}
 
@@ -323,19 +328,20 @@ sqsh_directory_iterator_next(struct SqshDirectoryIterator *iterator) {
 	rv = sqsh__metablock_reader_advance(
 			&iterator->metablock, iterator->next_offset, size);
 	if (rv < 0) {
-		return rv;
+		goto out;
 	}
 
 	/*  Make sure next entry has its name populated */
 	if (SQSH_ADD_OVERFLOW(
 				size, sqsh_directory_iterator_name_size(iterator), &size)) {
-		return -SQSH_ERROR_INTEGER_OVERFLOW;
+		rv = -SQSH_ERROR_INTEGER_OVERFLOW;
+		goto out;
 	}
 	/*  May invalidate pointers into directory entries. that's why the */
 	/*  get_entry() call is repeated below. */
 	rv = sqsh__metablock_reader_advance(&iterator->metablock, 0, size);
 	if (rv < 0) {
-		return rv;
+		goto out;
 	}
 
 	iterator->next_offset = size;
@@ -345,9 +351,15 @@ sqsh_directory_iterator_next(struct SqshDirectoryIterator *iterator) {
 	}
 	rv = check_consistency(iterator);
 	if (rv < 0) {
-		return rv;
+		goto out;
+	}
+
+	has_next = true;
+out:
+	if (err != NULL) {
+		*err = rv;
 	}
-	return 1;
+	return has_next;
 }
 
 const char *

lib/easy/directory.c

@@ -82,7 +82,7 @@ sqsh_easy_directory_list(
 		goto out;
 	}
 
-	while ((rv = sqsh_directory_iterator_next(iterator)) > 0) {
+	while (sqsh_directory_iterator_next(iterator, &rv)) {
 		const char *name = sqsh_directory_iterator_name(iterator);
 		size_t name_len = sqsh_directory_iterator_name_size(iterator);
 		size_t index = sqsh__buffer_size(&dir_list_names);

lib/tree/walker.c

@@ -172,13 +172,19 @@ sqsh_tree_walker_up(struct SqshTreeWalker *walker) {
 int
 sqsh_tree_walker_next(struct SqshTreeWalker *walker) {
 	struct SqshDirectoryIterator *iterator = &walker->iterator;
-	int rv = sqsh_directory_iterator_next(iterator);
+	int rv = 0;
 	walker->begin_iterator = false;
+
+	bool has_next = sqsh_directory_iterator_next(iterator, &rv);
 	if (rv < 0) {
 		return rv;
 	}
 
-	return update_inode_from_iterator(walker);
+	if (has_next == false) {
+		return 0;
+	} else {
+		return update_inode_from_iterator(walker);
+	}
 }
 
 enum SqshFileType

test/directory/directory_iterator.c

@@ -69,8 +69,9 @@ iter_invalid_file_name_with_0(void) {
 	rv = sqsh__directory_iterator_init(&iter, &file);
 	assert(rv == 0);
 
-	rv = sqsh_directory_iterator_next(&iter);
+	bool has_next = sqsh_directory_iterator_next(&iter, &rv);
 	assert(rv == -SQSH_ERROR_CORRUPTED_DIRECTORY_ENTRY);
+	assert(has_next == false);
 
 	sqsh__directory_iterator_cleanup(&iter);
 	sqsh__file_cleanup(&file);
@@ -105,8 +106,9 @@ iter_invalid_file_name_with_slash(void) {
 	rv = sqsh__directory_iterator_init(&iter, &file);
 	assert(rv == 0);
 
-	rv = sqsh_directory_iterator_next(&iter);
+	bool has_next = sqsh_directory_iterator_next(&iter, &rv);
 	assert(rv == -SQSH_ERROR_CORRUPTED_DIRECTORY_ENTRY);
+	assert(has_next == false);
 
 	sqsh__directory_iterator_cleanup(&iter);
 	sqsh__file_cleanup(&file);
@@ -150,16 +152,18 @@ iter_two_files(void) {
 	rv = sqsh__directory_iterator_init(&iter, &file);
 	assert(rv == 0);
 
-	rv = sqsh_directory_iterator_next(&iter);
-	assert(rv > 0);
+	bool has_next = sqsh_directory_iterator_next(&iter, &rv);
+	assert(rv == 0);
+	assert(has_next == true);
 
 	const char *name = sqsh_directory_iterator_name(&iter);
 	size_t size = sqsh_directory_iterator_name_size(&iter);
 	assert(size == 1);
 	assert(name[0] == '1');
 
-	rv = sqsh_directory_iterator_next(&iter);
-	assert(rv > 0);
+	has_next = sqsh_directory_iterator_next(&iter, &rv);
+	assert(rv == 0);
+	assert(has_next == true);
 
 	name = sqsh_directory_iterator_name(&iter);
 	size = sqsh_directory_iterator_name_size(&iter);

test/integration.c

@@ -136,30 +136,34 @@ sqsh_ls(void) {
 	assert(iter != NULL);
 	assert(rv == 0);
 
-	rv = sqsh_directory_iterator_next(iter);
-	assert(rv > 0);
+	bool has_next = sqsh_directory_iterator_next(iter, &rv);
+	assert(rv == 0);
+	assert(has_next);
 	name = sqsh_directory_iterator_name_dup(iter);
 	assert(name != NULL);
 	assert(strcmp("a", name) == 0);
 	free(name);
 
-	rv = sqsh_directory_iterator_next(iter);
+	has_next = sqsh_directory_iterator_next(iter, &rv);
 	assert(rv >= 0);
+	assert(has_next == true);
 	name = sqsh_directory_iterator_name_dup(iter);
 	assert(name != NULL);
 	assert(strcmp("b", name) == 0);
 	free(name);
 
-	rv = sqsh_directory_iterator_next(iter);
-	assert(rv >= 0);
+	has_next = sqsh_directory_iterator_next(iter, &rv);
+	assert(rv == 0);
+	assert(has_next == true);
 	name = sqsh_directory_iterator_name_dup(iter);
 	assert(name != NULL);
 	assert(strcmp("large_dir", name) == 0);
 	free(name);
 
-	rv = sqsh_directory_iterator_next(iter);
+	has_next = sqsh_directory_iterator_next(iter, &rv);
 	// End of file list
 	assert(rv == 0);
+	assert(has_next == false);
 
 	rv = sqsh_directory_iterator_free(iter);
 	assert(rv == 0);
@@ -529,7 +533,7 @@ multithreaded_walker(void *arg) {
 	if (sqsh_file_type(file) == SQSH_FILE_TYPE_DIRECTORY) {
 		struct SqshDirectoryIterator *iter =
 				sqsh_directory_iterator_new(file, &rv);
-		while (sqsh_directory_iterator_next(iter) > 0) {
+		while (sqsh_directory_iterator_next(iter, &rv) > 0) {
 			multithreaded_walker(&my_walker);
 		}
 		sqsh_directory_iterator_free(iter);

tools/fs2.c

@@ -140,12 +140,15 @@ fs_readdir(
 	}
 	filler(buf, ".", NULL, 0);
 	filler(buf, "..", NULL, 0);
-	while ((rv = sqsh_directory_iterator_next(iterator)) > 0) {
+	while (sqsh_directory_iterator_next(iterator, &rv)) {
 		rv = fs_readdir_item(buf, iterator, filler);
 		if (rv < 0) {
-			goto out;
+			break;
 		}
 	}
+	if (rv < 0) {
+		goto out;
+	}
 
 out:
 	sqsh_directory_iterator_free(iterator);

tools/fs3.c

@@ -261,11 +261,11 @@ fs_readdir(
 	struct FsDirHandle *handle = get_dir_handle(fi);
 	char buf[size];
 
-	rv = sqsh_directory_iterator_next(handle->iterator);
+	bool has_next = sqsh_directory_iterator_next(handle->iterator, &rv);
 	if (rv < 0) {
 		fuse_reply_err(req, -fs_common_map_err(rv));
 		goto out;
-	} else if (rv == 0) {
+	} else if (has_next == false) {
 		fuse_reply_buf(req, NULL, 0);
 		goto out;
 	}

tools/ls.c

@@ -201,13 +201,16 @@ ls(struct SqshArchive *archive, const char *path, struct SqshFile *file) {
 		goto out;
 	}
 
-	while (sqsh_directory_iterator_next(iter) > 0) {
+	while (sqsh_directory_iterator_next(iter, &rv)) {
 		rv = ls_item(archive, path, iter);
 		if (rv < 0) {
-			rv = EXIT_FAILURE;
-			goto out;
+			break;
 		}
 	}
+	if (rv < 0) {
+		rv = EXIT_FAILURE;
+		goto out;
+	}
 
 out:
 	sqsh_directory_iterator_free(iter);

tools/unpack.c

@@ -138,13 +138,17 @@ extract_directory(
 		goto out;
 	}
 
-	while (sqsh_directory_iterator_next(iter) > 0) {
+	while (sqsh_directory_iterator_next(iter, &rv)) {
 		rv = extract_directory_entry(iter, path_stack);
 		// Don't stop on error, but continue with next entry.
 		/*if (rv < 0) {
 			goto out;
 		}*/
 	}
+	if (rv < 0) {
+		print_err(rv, "sqsh_directory_iterator_next", path_stack);
+		goto out;
+	}
 
 	rv = chdir(cwd);
 	if (rv < 0) {