diff options
Diffstat (limited to 'extras/extract_one.c')
| -rw-r--r-- | extras/extract_one.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/extras/extract_one.c b/extras/extract_one.c new file mode 100644 index 0000000..4f5b547 --- /dev/null +++ b/extras/extract_one.c @@ -0,0 +1,184 @@ +/* SPDX-License-Identifier: 0BSD */ +/* + * extract_one.c + * + * Copyright (C) 2021 Luca Boccassi <luca.boccassi@microsoft.com> + */ + +#include "sqfs/compressor.h" +#include "sqfs/data_reader.h" +#include "sqfs/dir_reader.h" +#include "sqfs/error.h" +#include "sqfs/id_table.h" +#include "sqfs/io.h" +#include "sqfs/inode.h" +#include "sqfs/super.h" +#include "sqfs/xattr_reader.h" + +#include <string.h> +#include <stdlib.h> +#include <errno.h> +#include <stdio.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> + +int main(int argc, char **argv) +{ + sqfs_xattr_reader_t *xattr = NULL; + sqfs_data_reader_t *data = NULL; + sqfs_dir_reader_t *dirrd = NULL; + sqfs_compressor_t *cmp = NULL; + sqfs_id_table_t *idtbl = NULL; + sqfs_tree_node_t *n = NULL; + sqfs_file_t *file = NULL; + sqfs_u8 *p, *output = NULL; + sqfs_compressor_config_t cfg; + sqfs_super_t super; + sqfs_u64 file_size; + int status = EXIT_FAILURE, ret; + + if (argc != 3) { + fputs("Usage: extract_one <squashfs-file> <source-file-path>\n", stderr); + return EXIT_FAILURE; + } + + file = sqfs_open_file(argv[1], SQFS_FILE_OPEN_READ_ONLY); + if (file == NULL) { + perror(argv[1]); + return EXIT_FAILURE; + } + + ret = sqfs_super_read(&super, file); + if (ret) { + fprintf(stderr, "%s: error reading super block.\n", argv[1]); + goto out_file; + } + + sqfs_compressor_config_init(&cfg, super.compression_id, + super.block_size, + SQFS_COMP_FLAG_UNCOMPRESS); + + ret = sqfs_compressor_create(&cfg, &cmp); + if (ret != 0) { + fprintf(stderr, "%s: error creating compressor: %d.\n", argv[1], ret); + goto out_file; + } + + if (!(super.flags & SQFS_FLAG_NO_XATTRS)) { + xattr = sqfs_xattr_reader_create(0); + if (xattr == NULL) { + fprintf(stderr, "%s: error creating xattr reader: %d.\n", argv[1], SQFS_ERROR_ALLOC); + goto out_cmp; + } + + ret = sqfs_xattr_reader_load(xattr, &super, file, cmp); + if (ret) { + fprintf(stderr, "%s: error loading xattr reader: %d.\n", argv[1], ret); + goto out_xattr; + } + } + + idtbl = sqfs_id_table_create(0); + if (idtbl == NULL) { + fprintf(stderr, "%s: error creating ID table: %d.\n", argv[1], ret); + goto out_xattr; + } + + ret = sqfs_id_table_read(idtbl, file, &super, cmp); + if (ret) { + fprintf(stderr, "%s: error loading ID table: %d.\n", argv[1], ret); + goto out_idtbl; + } + + dirrd = sqfs_dir_reader_create(&super, cmp, file, 0); + if (dirrd == NULL) { + fprintf(stderr, "%s: error creating dir reader: %d.\n", argv[1], SQFS_ERROR_ALLOC); + goto out_idtbl; + } + + data = sqfs_data_reader_create(file, super.block_size, cmp, 0); + if (data == NULL) { + fprintf(stderr, "%s: error creating data reader: %d.\n", argv[1], SQFS_ERROR_ALLOC); + goto out_dirrd; + } + + ret = sqfs_data_reader_load_fragment_table(data, &super); + if (ret) { + fprintf(stderr, "%s: error loading fragment table: %d.\n", argv[1], ret); + goto out_data; + } + + ret = sqfs_dir_reader_get_full_hierarchy(dirrd, idtbl, argv[2], 0, &n); + if (ret) { + fprintf(stderr, "%s: error reading filesystem hierarchy: %d.\n", argv[1], ret); + goto out_data; + } + + if (!S_ISREG(n->inode->base.mode)) { + fprintf(stderr, "/%s is not a file\n", argv[2]); + goto out_tree; + } + + sqfs_inode_get_file_size(n->inode, &file_size); + + output = p = malloc(file_size); + if (output == NULL) { + fprintf(stderr, "malloc failed: %d\n", errno); + goto out_tree; + } + + for (size_t i = 0; i < sqfs_inode_get_file_block_count(n->inode); ++i) { + size_t chunk_size, read = (file_size < super.block_size) ? file_size : super.block_size; + sqfs_u8 *chunk; + + ret = sqfs_data_reader_get_block(data, n->inode, i, &chunk_size, &chunk); + if (ret) { + fprintf(stderr, "reading data block: %d\n", ret); + goto out_tree; + } + + memcpy(p, chunk, chunk_size); + p += chunk_size; + free(chunk); + + file_size -= read; + } + + if (file_size > 0) { + size_t chunk_size; + sqfs_u8 *chunk; + + ret = sqfs_data_reader_get_fragment(data, n->inode, &chunk_size, &chunk); + if (ret) { + fprintf(stderr, "reading fragment block: %d\n", ret); + goto out_tree; + } + + memcpy(p, chunk, chunk_size); + free(chunk); + } + + /* for example simplicity, assume this is a text file */ + fprintf(stdout, "%s\n", (char *)output); + + status = EXIT_SUCCESS; +out_tree: + sqfs_dir_tree_destroy(n); +out_data: + sqfs_destroy(data); +out_dirrd: + sqfs_destroy(dirrd); +out_idtbl: + sqfs_destroy(idtbl); +out_xattr: + if (xattr != NULL) + sqfs_destroy(xattr); +out_cmp: + sqfs_destroy(cmp); +out_file: + sqfs_destroy(file); + free(output); + + return status; +} |