From 9d431639effb4e33169110031a689fd1e9d435cf Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Tue, 18 Jul 2023 20:44:01 +0200 Subject: 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 --- lib/sqfs/src/io/dir_rec.c | 253 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 253 insertions(+) create mode 100644 lib/sqfs/src/io/dir_rec.c (limited to 'lib/sqfs/src/io') diff --git a/lib/sqfs/src/io/dir_rec.c b/lib/sqfs/src/io/dir_rec.c new file mode 100644 index 0000000..a5d53af --- /dev/null +++ b/lib/sqfs/src/io/dir_rec.c @@ -0,0 +1,253 @@ +/* SPDX-License-Identifier: LGPL-3.0-or-later */ +/* + * dir_rec.c + * + * Copyright (C) 2023 David Oberhollenzer + */ +#define SQFS_BUILDING_DLL +#include "config.h" + +#include "util/util.h" +#include "sqfs/dir_entry.h" +#include "sqfs/error.h" +#include "sqfs/io.h" + +#include +#include + +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; + + int state; + dir_stack_t *top; + + dir_stack_t *next_top; +} 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 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; + char *dst; + void *new; + + for (dir_stack_t *sit = it->top; sit != NULL; sit = sit->next) { + if (sit->name[0] != '\0') + plen += strlen(sit->name) + 1; + } + + if (plen == 0) + return ent; + + new = realloc(ent, sizeof(*ent) + plen + slen); + if (new == NULL) { + free(ent); + return NULL; + } + + ent = new; + memmove(ent->name + plen, ent->name, slen); + dst = ent->name + plen; + + for (dir_stack_t *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); + } + } + + return ent; +} + +/*****************************************************************************/ + +static void destroy(sqfs_object_t *obj) +{ + dir_tree_iterator_t *it = (dir_tree_iterator_t *)obj; + + while (it->top != NULL) + pop(it); + + if (it->next_top != NULL) { + sqfs_drop(it->next_top->dir); + free(it->next_top); + } + + 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_entry_t *ent = NULL; + int ret; + + *out = NULL; + if (it->state != 0) + return it->state; + + if (it->next_top != NULL) { + it->next_top->next = it->top; + it->top = it->next_top; + it->next_top = NULL; + } + + 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; + } + + if (!strcmp(ent->name, ".") || !strcmp(ent->name, "..")) { + free(ent); + ent = NULL; + continue; + } + + break; + } + + ent = expand_path(it, ent); + if (ent == NULL) { + it->state = SQFS_ERROR_ALLOC; + return it->state; + } + + if (S_ISDIR(ent->mode)) { + sqfs_dir_iterator_t *sub = NULL; + 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; + + it->next_top = alloc_flex(sizeof(*(it->next_top)), 1, + strlen(name) + 1); + if (it->next_top == NULL) { + sqfs_drop(sub); + goto fail; + } + + strcpy(it->next_top->name, name); + it->next_top->dir = sub; + } + + *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; + + *out = NULL; + if (it->top == NULL) + return SQFS_ERROR_NO_ENTRY; + + return it->top->dir->read_link(it->top->dir, 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; + + *out = NULL; + if (it->top == NULL) + return SQFS_ERROR_NO_ENTRY; + + return it->top->dir->open_subdir(it->top->dir, out); +} + +static void ignore_subdir(sqfs_dir_iterator_t *base) +{ + dir_tree_iterator_t *it = (dir_tree_iterator_t *)base; + + if (it->next_top != NULL) { + sqfs_drop(it->next_top->dir); + free(it->next_top); + it->next_top = NULL; + } +} + +static int open_file_ro(sqfs_dir_iterator_t *base, sqfs_istream_t **out) +{ + dir_tree_iterator_t *it = (dir_tree_iterator_t *)base; + + *out = NULL; + if (it->top == NULL) + return SQFS_ERROR_NO_ENTRY; + + return it->top->dir->open_file_ro(it->top->dir, out); +} + +static int read_xattr(sqfs_dir_iterator_t *base, sqfs_xattr_t **out) +{ + dir_tree_iterator_t *it = (dir_tree_iterator_t *)base; + + *out = NULL; + if (it->top == NULL) + return SQFS_ERROR_NO_ENTRY; + + return it->top->dir->read_xattr(it->top->dir, out); +} + +int sqfs_dir_iterator_create_recursive(sqfs_dir_iterator_t **out, + sqfs_dir_iterator_t *base) +{ + dir_tree_iterator_t *it = calloc(1, sizeof(*it)); + + *out = NULL; + if (it == NULL) + return SQFS_ERROR_ALLOC; + + it->next_top = calloc(1, sizeof(*(it->next_top)) + 1); + if (it->next_top == NULL) { + free(it); + return SQFS_ERROR_ALLOC; + } + it->next_top->dir = sqfs_grab(base); + + sqfs_object_init(it, destroy, NULL); + ((sqfs_dir_iterator_t *)it)->next = next; + ((sqfs_dir_iterator_t *)it)->read_link = read_link; + ((sqfs_dir_iterator_t *)it)->open_subdir = open_subdir; + ((sqfs_dir_iterator_t *)it)->ignore_subdir = ignore_subdir; + ((sqfs_dir_iterator_t *)it)->open_file_ro = open_file_ro; + ((sqfs_dir_iterator_t *)it)->read_xattr = read_xattr; + + *out = (sqfs_dir_iterator_t *)it; + return 0; +} -- cgit v1.2.3