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authorDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2022-04-04 17:45:01 +0200
committerDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2022-04-05 20:19:56 +0200
commit94c3fdc66b9aa8130b20a644f399fc021d0a823c (patch)
tree5a841462555e39f78b6ab863a7d695d257daa6a7 /lib/sqfs/dir_reader
parent916c8f6e26140cf3c03e58726b57dc4f86e18316 (diff)
libsqfs: move dir reader code to sub directory, add internal header
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Diffstat (limited to 'lib/sqfs/dir_reader')
-rw-r--r--lib/sqfs/dir_reader/dir_reader.c232
-rw-r--r--lib/sqfs/dir_reader/find_by_path.c82
-rw-r--r--lib/sqfs/dir_reader/internal.h42
-rw-r--r--lib/sqfs/dir_reader/read_tree.c292
4 files changed, 648 insertions, 0 deletions
diff --git a/lib/sqfs/dir_reader/dir_reader.c b/lib/sqfs/dir_reader/dir_reader.c
new file mode 100644
index 0000000..969b71d
--- /dev/null
+++ b/lib/sqfs/dir_reader/dir_reader.c
@@ -0,0 +1,232 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * fs_reader.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+static void dir_reader_destroy(sqfs_object_t *obj)
+{
+ sqfs_dir_reader_t *rd = (sqfs_dir_reader_t *)obj;
+
+ sqfs_destroy(rd->meta_inode);
+ sqfs_destroy(rd->meta_dir);
+ free(rd);
+}
+
+static sqfs_object_t *dir_reader_copy(const sqfs_object_t *obj)
+{
+ const sqfs_dir_reader_t *rd = (const sqfs_dir_reader_t *)obj;
+ sqfs_dir_reader_t *copy = malloc(sizeof(*copy));
+
+ if (copy == NULL)
+ return NULL;
+
+ memcpy(copy, rd, sizeof(*copy));
+
+ copy->meta_inode = sqfs_copy(rd->meta_inode);
+ if (copy->meta_inode == NULL)
+ goto fail_mino;
+
+ copy->meta_dir = sqfs_copy(rd->meta_dir);
+ if (copy->meta_dir == NULL)
+ goto fail_mdir;
+
+ return (sqfs_object_t *)copy;
+fail_mdir:
+ sqfs_destroy(copy->meta_inode);
+fail_mino:
+ free(copy);
+ return NULL;
+}
+
+sqfs_dir_reader_t *sqfs_dir_reader_create(const sqfs_super_t *super,
+ sqfs_compressor_t *cmp,
+ sqfs_file_t *file,
+ sqfs_u32 flags)
+{
+ sqfs_dir_reader_t *rd;
+ sqfs_u64 start, limit;
+
+ if (flags != 0)
+ return NULL;
+
+ rd = calloc(1, sizeof(*rd));
+ if (rd == NULL)
+ return NULL;
+
+ start = super->inode_table_start;
+ limit = super->directory_table_start;
+
+ rd->meta_inode = sqfs_meta_reader_create(file, cmp, start, limit);
+
+ if (rd->meta_inode == NULL) {
+ free(rd);
+ return NULL;
+ }
+
+ start = super->directory_table_start;
+ limit = super->id_table_start;
+
+ if (super->fragment_table_start < limit)
+ limit = super->fragment_table_start;
+
+ if (super->export_table_start < limit)
+ limit = super->export_table_start;
+
+ rd->meta_dir = sqfs_meta_reader_create(file, cmp, start, limit);
+
+ if (rd->meta_dir == NULL) {
+ sqfs_destroy(rd->meta_inode);
+ free(rd);
+ return NULL;
+ }
+
+ ((sqfs_object_t *)rd)->destroy = dir_reader_destroy;
+ ((sqfs_object_t *)rd)->copy = dir_reader_copy;
+ rd->super = super;
+ return rd;
+}
+
+int sqfs_dir_reader_open_dir(sqfs_dir_reader_t *rd,
+ const sqfs_inode_generic_t *inode,
+ sqfs_u32 flags)
+{
+ sqfs_u64 block_start;
+ size_t size, offset;
+
+ if (flags != 0)
+ return SQFS_ERROR_UNSUPPORTED;
+
+ if (inode->base.type == SQFS_INODE_DIR) {
+ size = inode->data.dir.size;
+ offset = inode->data.dir.offset;
+ block_start = inode->data.dir.start_block;
+ } else if (inode->base.type == SQFS_INODE_EXT_DIR) {
+ size = inode->data.dir_ext.size;
+ offset = inode->data.dir_ext.offset;
+ block_start = inode->data.dir_ext.start_block;
+ } else {
+ return SQFS_ERROR_NOT_DIR;
+ }
+
+ memset(&rd->hdr, 0, sizeof(rd->hdr));
+ rd->size = size;
+ rd->entries = 0;
+
+ block_start += rd->super->directory_table_start;
+
+ rd->dir_block_start = block_start;
+ rd->dir_offset = offset;
+ rd->start_size = size;
+
+ if (rd->size <= sizeof(rd->hdr))
+ return 0;
+
+ return sqfs_meta_reader_seek(rd->meta_dir, block_start, offset);
+}
+
+int sqfs_dir_reader_read(sqfs_dir_reader_t *rd, sqfs_dir_entry_t **out)
+{
+ sqfs_dir_entry_t *ent;
+ size_t count;
+ int err;
+
+ if (!rd->entries) {
+ if (rd->size <= sizeof(rd->hdr))
+ return 1;
+
+ err = sqfs_meta_reader_read_dir_header(rd->meta_dir, &rd->hdr);
+ if (err)
+ return err;
+
+ rd->size -= sizeof(rd->hdr);
+ rd->entries = rd->hdr.count + 1;
+ }
+
+ if (rd->size <= sizeof(*ent)) {
+ rd->size = 0;
+ rd->entries = 0;
+ return 1;
+ }
+
+ err = sqfs_meta_reader_read_dir_ent(rd->meta_dir, &ent);
+ if (err)
+ return err;
+
+ count = sizeof(*ent) + strlen((const char *)ent->name);
+
+ if (count > rd->size) {
+ rd->size = 0;
+ rd->entries = 0;
+ } else {
+ rd->size -= count;
+ rd->entries -= 1;
+ }
+
+ rd->inode_offset = ent->offset;
+ *out = ent;
+ return 0;
+}
+
+int sqfs_dir_reader_rewind(sqfs_dir_reader_t *rd)
+{
+ memset(&rd->hdr, 0, sizeof(rd->hdr));
+ rd->size = rd->start_size;
+ rd->entries = 0;
+
+ if (rd->size <= sizeof(rd->hdr))
+ return 0;
+
+ return sqfs_meta_reader_seek(rd->meta_dir, rd->dir_block_start,
+ rd->dir_offset);
+}
+
+int sqfs_dir_reader_find(sqfs_dir_reader_t *rd, const char *name)
+{
+ sqfs_dir_entry_t *ent;
+ int ret;
+
+ if (rd->size != rd->start_size) {
+ ret = sqfs_dir_reader_rewind(rd);
+ if (ret)
+ return ret;
+ }
+
+ do {
+ ret = sqfs_dir_reader_read(rd, &ent);
+ if (ret < 0)
+ return ret;
+ if (ret > 0)
+ return SQFS_ERROR_NO_ENTRY;
+
+ ret = strcmp((const char *)ent->name, name);
+ free(ent);
+ } while (ret < 0);
+
+ return ret == 0 ? 0 : SQFS_ERROR_NO_ENTRY;
+}
+
+int sqfs_dir_reader_get_inode(sqfs_dir_reader_t *rd,
+ sqfs_inode_generic_t **inode)
+{
+ sqfs_u64 block_start;
+
+ block_start = rd->hdr.start_block;
+
+ return sqfs_meta_reader_read_inode(rd->meta_inode, rd->super,
+ block_start, rd->inode_offset,
+ inode);
+}
+
+int sqfs_dir_reader_get_root_inode(sqfs_dir_reader_t *rd,
+ sqfs_inode_generic_t **inode)
+{
+ sqfs_u64 block_start = rd->super->root_inode_ref >> 16;
+ sqfs_u16 offset = rd->super->root_inode_ref & 0xFFFF;
+
+ return sqfs_meta_reader_read_inode(rd->meta_inode, rd->super,
+ block_start, offset, inode);
+}
diff --git a/lib/sqfs/dir_reader/find_by_path.c b/lib/sqfs/dir_reader/find_by_path.c
new file mode 100644
index 0000000..0cd800f
--- /dev/null
+++ b/lib/sqfs/dir_reader/find_by_path.c
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * find_by_path.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+int sqfs_dir_reader_find_by_path(sqfs_dir_reader_t *rd,
+ const sqfs_inode_generic_t *start,
+ const char *path, sqfs_inode_generic_t **out)
+{
+ sqfs_inode_generic_t *inode;
+ sqfs_dir_entry_t *ent;
+ const char *ptr;
+ int ret = 0;
+
+ if (start == NULL) {
+ ret = sqfs_dir_reader_get_root_inode(rd, &inode);
+ } else {
+ inode = alloc_flex(sizeof(*inode), 1,
+ start->payload_bytes_used);
+ if (inode == NULL) {
+ ret = SQFS_ERROR_ALLOC;
+ } else {
+ memcpy(inode, start,
+ sizeof(*start) + start->payload_bytes_used);
+ }
+ }
+
+ if (ret)
+ return ret;
+
+ while (*path != '\0') {
+ if (*path == '/') {
+ while (*path == '/')
+ ++path;
+ continue;
+ }
+
+ ret = sqfs_dir_reader_open_dir(rd, inode, 0);
+ free(inode);
+ if (ret)
+ return ret;
+
+ ptr = strchr(path, '/');
+ if (ptr == NULL) {
+
+ if (ptr == NULL) {
+ for (ptr = path; *ptr != '\0'; ++ptr)
+ ;
+ }
+ }
+
+ do {
+ ret = sqfs_dir_reader_read(rd, &ent);
+ if (ret < 0)
+ return ret;
+
+ if (ret == 0) {
+ ret = strncmp((const char *)ent->name,
+ path, ptr - path);
+ if (ret == 0)
+ ret = ent->name[ptr - path];
+ free(ent);
+ }
+ } while (ret < 0);
+
+ if (ret > 0)
+ return SQFS_ERROR_NO_ENTRY;
+
+ ret = sqfs_dir_reader_get_inode(rd, &inode);
+ if (ret)
+ return ret;
+
+ path = ptr;
+ }
+
+ *out = inode;
+ return 0;
+}
diff --git a/lib/sqfs/dir_reader/internal.h b/lib/sqfs/dir_reader/internal.h
new file mode 100644
index 0000000..ff162ff
--- /dev/null
+++ b/lib/sqfs/dir_reader/internal.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * internal.h
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#ifndef DIR_READER_INTERNAL_H
+#define DIR_READER_INTERNAL_H
+
+#include "config.h"
+
+#include "sqfs/meta_reader.h"
+#include "sqfs/dir_reader.h"
+#include "sqfs/compressor.h"
+#include "sqfs/id_table.h"
+#include "sqfs/super.h"
+#include "sqfs/inode.h"
+#include "sqfs/error.h"
+#include "sqfs/dir.h"
+#include "util.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+struct sqfs_dir_reader_t {
+ sqfs_object_t base;
+
+ sqfs_meta_reader_t *meta_dir;
+ sqfs_meta_reader_t *meta_inode;
+ const sqfs_super_t *super;
+
+ sqfs_dir_header_t hdr;
+ sqfs_u64 dir_block_start;
+ size_t entries;
+ size_t size;
+
+ size_t start_size;
+ sqfs_u16 dir_offset;
+ sqfs_u16 inode_offset;
+};
+
+#endif /* DIR_READER_INTERNAL_H */
diff --git a/lib/sqfs/dir_reader/read_tree.c b/lib/sqfs/dir_reader/read_tree.c
new file mode 100644
index 0000000..d173ef7
--- /dev/null
+++ b/lib/sqfs/dir_reader/read_tree.c
@@ -0,0 +1,292 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * read_tree.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+static int should_skip(int type, unsigned int flags)
+{
+ switch (type) {
+ case SQFS_INODE_BDEV:
+ case SQFS_INODE_CDEV:
+ case SQFS_INODE_EXT_CDEV:
+ case SQFS_INODE_EXT_BDEV:
+ return (flags & SQFS_TREE_NO_DEVICES);
+ case SQFS_INODE_SLINK:
+ case SQFS_INODE_EXT_SLINK:
+ return (flags & SQFS_TREE_NO_SLINKS);
+ case SQFS_INODE_SOCKET:
+ case SQFS_INODE_EXT_SOCKET:
+ return(flags & SQFS_TREE_NO_SOCKETS);
+ case SQFS_INODE_FIFO:
+ case SQFS_INODE_EXT_FIFO:
+ return (flags & SQFS_TREE_NO_FIFO);
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static bool would_be_own_parent(sqfs_tree_node_t *parent, sqfs_tree_node_t *n)
+{
+ sqfs_u32 inum = n->inode->base.inode_number;
+
+ while (parent != NULL) {
+ if (parent->inode->base.inode_number == inum)
+ return true;
+
+ parent = parent->parent;
+ }
+
+ return false;
+}
+
+static sqfs_tree_node_t *create_node(sqfs_inode_generic_t *inode,
+ const char *name)
+{
+ sqfs_tree_node_t *n;
+
+ n = alloc_flex(sizeof(*n), 1, strlen(name) + 1);
+ if (n == NULL)
+ return NULL;
+
+ n->inode = inode;
+ strcpy((char *)n->name, name);
+ return n;
+}
+
+static int fill_dir(sqfs_dir_reader_t *dr, sqfs_tree_node_t *root,
+ unsigned int flags)
+{
+ sqfs_tree_node_t *n, *prev, **tail;
+ sqfs_inode_generic_t *inode;
+ sqfs_dir_entry_t *ent;
+ int err;
+
+ tail = &root->children;
+
+ for (;;) {
+ err = sqfs_dir_reader_read(dr, &ent);
+ if (err > 0)
+ break;
+ if (err < 0)
+ return err;
+
+ if (should_skip(ent->type, flags)) {
+ free(ent);
+ continue;
+ }
+
+ err = sqfs_dir_reader_get_inode(dr, &inode);
+ if (err) {
+ free(ent);
+ return err;
+ }
+
+ n = create_node(inode, (const char *)ent->name);
+ free(ent);
+
+ if (n == NULL) {
+ free(inode);
+ return SQFS_ERROR_ALLOC;
+ }
+
+ if (would_be_own_parent(root, n)) {
+ free(n);
+ free(inode);
+ return SQFS_ERROR_LINK_LOOP;
+ }
+
+ *tail = n;
+ tail = &n->next;
+ n->parent = root;
+ }
+
+ n = root->children;
+ prev = NULL;
+
+ while (n != NULL) {
+ if (n->inode->base.type == SQFS_INODE_DIR ||
+ n->inode->base.type == SQFS_INODE_EXT_DIR) {
+ if (!(flags & SQFS_TREE_NO_RECURSE)) {
+ err = sqfs_dir_reader_open_dir(dr, n->inode, 0);
+ if (err)
+ return err;
+
+ err = fill_dir(dr, n, flags);
+ if (err)
+ return err;
+ }
+
+ if (n->children == NULL &&
+ (flags & SQFS_TREE_NO_EMPTY)) {
+ free(n->inode);
+ if (prev == NULL) {
+ root->children = root->children->next;
+ free(n);
+ n = root->children;
+ } else {
+ prev->next = n->next;
+ free(n);
+ n = prev->next;
+ }
+ continue;
+ }
+ }
+
+ prev = n;
+ n = n->next;
+ }
+
+ return 0;
+}
+
+static int resolve_ids(sqfs_tree_node_t *root, const sqfs_id_table_t *idtbl)
+{
+ sqfs_tree_node_t *it;
+ int err;
+
+ for (it = root->children; it != NULL; it = it->next)
+ resolve_ids(it, idtbl);
+
+ err = sqfs_id_table_index_to_id(idtbl, root->inode->base.uid_idx,
+ &root->uid);
+ if (err)
+ return err;
+
+ return sqfs_id_table_index_to_id(idtbl, root->inode->base.gid_idx,
+ &root->gid);
+}
+
+void sqfs_dir_tree_destroy(sqfs_tree_node_t *root)
+{
+ sqfs_tree_node_t *it;
+
+ if (!root)
+ return;
+
+ while (root->children != NULL) {
+ it = root->children;
+ root->children = it->next;
+
+ sqfs_dir_tree_destroy(it);
+ }
+
+ free(root->inode);
+ free(root);
+}
+
+int sqfs_dir_reader_get_full_hierarchy(sqfs_dir_reader_t *rd,
+ const sqfs_id_table_t *idtbl,
+ const char *path, unsigned int flags,
+ sqfs_tree_node_t **out)
+{
+ sqfs_tree_node_t *root, *tail, *new;
+ sqfs_inode_generic_t *inode;
+ sqfs_dir_entry_t *ent;
+ const char *ptr;
+ int ret;
+
+ if (flags & ~SQFS_TREE_ALL_FLAGS)
+ return SQFS_ERROR_UNSUPPORTED;
+
+ ret = sqfs_dir_reader_get_root_inode(rd, &inode);
+ if (ret)
+ return ret;
+
+ root = tail = create_node(inode, "");
+ if (root == NULL) {
+ free(inode);
+ return SQFS_ERROR_ALLOC;
+ }
+ inode = NULL;
+
+ while (path != NULL && *path != '\0') {
+ if (*path == '/') {
+ while (*path == '/')
+ ++path;
+ continue;
+ }
+
+ ret = sqfs_dir_reader_open_dir(rd, tail->inode, 0);
+ if (ret)
+ goto fail;
+
+ ptr = strchr(path, '/');
+ if (ptr == NULL) {
+
+ if (ptr == NULL) {
+ for (ptr = path; *ptr != '\0'; ++ptr)
+ ;
+ }
+ }
+
+ for (;;) {
+ ret = sqfs_dir_reader_read(rd, &ent);
+ if (ret < 0)
+ goto fail;
+ if (ret > 0) {
+ ret = SQFS_ERROR_NO_ENTRY;
+ goto fail;
+ }
+
+ ret = strncmp((const char *)ent->name,
+ path, ptr - path);
+ if (ret == 0 && ent->name[ptr - path] == '\0')
+ break;
+ free(ent);
+ }
+
+ ret = sqfs_dir_reader_get_inode(rd, &inode);
+ if (ret) {
+ free(ent);
+ goto fail;
+ }
+
+ new = create_node(inode, (const char *)ent->name);
+ free(ent);
+
+ if (new == NULL) {
+ free(inode);
+ ret = SQFS_ERROR_ALLOC;
+ goto fail;
+ }
+
+ inode = NULL;
+ path = ptr;
+
+ if (flags & SQFS_TREE_STORE_PARENTS) {
+ tail->children = new;
+ new->parent = tail;
+ tail = new;
+ } else {
+ sqfs_dir_tree_destroy(root);
+ root = tail = new;
+ }
+ }
+
+ if (tail->inode->base.type == SQFS_INODE_DIR ||
+ tail->inode->base.type == SQFS_INODE_EXT_DIR) {
+ ret = sqfs_dir_reader_open_dir(rd, tail->inode, 0);
+ if (ret)
+ goto fail;
+
+ ret = fill_dir(rd, tail, flags);
+ if (ret)
+ goto fail;
+ }
+
+ ret = resolve_ids(root, idtbl);
+ if (ret)
+ goto fail;
+
+ *out = root;
+ return 0;
+fail:
+ sqfs_dir_tree_destroy(root);
+ return ret;
+}