| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | #include <errno.h> |
| 3 | #include <lzma.h> |
| 4 | #include <stdio.h> |
| 5 | #include <linux/compiler.h> |
| 6 | #include <sys/types.h> |
| 7 | #include <sys/stat.h> |
| 8 | #include <fcntl.h> |
| 9 | #include "compress.h" |
| 10 | #include "debug.h" |
| 11 | #include <string.h> |
| 12 | #include <unistd.h> |
| 13 | #include <internal/lib.h> |
| 14 | |
| 15 | #define BUFSIZE 8192 |
| 16 | |
| 17 | static const char *lzma_strerror(lzma_ret ret) |
| 18 | { |
| 19 | switch ((int) ret) { |
| 20 | case LZMA_MEM_ERROR: |
| 21 | return "Memory allocation failed"; |
| 22 | case LZMA_OPTIONS_ERROR: |
| 23 | return "Unsupported decompressor flags"; |
| 24 | case LZMA_FORMAT_ERROR: |
| 25 | return "The input is not in the .xz format"; |
| 26 | case LZMA_DATA_ERROR: |
| 27 | return "Compressed file is corrupt"; |
| 28 | case LZMA_BUF_ERROR: |
| 29 | return "Compressed file is truncated or otherwise corrupt"; |
| 30 | default: |
| 31 | return "Unknown error, possibly a bug"; |
| 32 | } |
| 33 | } |
| 34 | |
| 35 | int lzma_decompress_to_file(const char *input, int output_fd) |
| 36 | { |
| 37 | lzma_action action = LZMA_RUN; |
| 38 | lzma_stream strm = LZMA_STREAM_INIT; |
| 39 | lzma_ret ret; |
| 40 | int err = -1; |
| 41 | |
| 42 | u8 buf_in[BUFSIZE]; |
| 43 | u8 buf_out[BUFSIZE]; |
| 44 | FILE *infile; |
| 45 | |
| 46 | infile = fopen(input, "rb"); |
| 47 | if (!infile) { |
| 48 | pr_err("lzma: fopen failed on %s: '%s'\n", |
| 49 | input, strerror(errno)); |
| 50 | return -1; |
| 51 | } |
| 52 | |
| 53 | ret = lzma_stream_decoder(&strm, UINT64_MAX, LZMA_CONCATENATED); |
| 54 | if (ret != LZMA_OK) { |
| 55 | pr_err("lzma: lzma_stream_decoder failed %s (%d)\n", |
| 56 | lzma_strerror(ret), ret); |
| 57 | goto err_fclose; |
| 58 | } |
| 59 | |
| 60 | strm.next_in = NULL; |
| 61 | strm.avail_in = 0; |
| 62 | strm.next_out = buf_out; |
| 63 | strm.avail_out = sizeof(buf_out); |
| 64 | |
| 65 | while (1) { |
| 66 | if (strm.avail_in == 0 && !feof(infile)) { |
| 67 | strm.next_in = buf_in; |
| 68 | strm.avail_in = fread(buf_in, 1, sizeof(buf_in), infile); |
| 69 | |
| 70 | if (ferror(infile)) { |
| 71 | pr_err("lzma: read error: %s\n", strerror(errno)); |
| 72 | goto err_lzma_end; |
| 73 | } |
| 74 | |
| 75 | if (feof(infile)) |
| 76 | action = LZMA_FINISH; |
| 77 | } |
| 78 | |
| 79 | ret = lzma_code(&strm, action); |
| 80 | |
| 81 | if (strm.avail_out == 0 || ret == LZMA_STREAM_END) { |
| 82 | ssize_t write_size = sizeof(buf_out) - strm.avail_out; |
| 83 | |
| 84 | if (writen(output_fd, buf_out, write_size) != write_size) { |
| 85 | pr_err("lzma: write error: %s\n", strerror(errno)); |
| 86 | goto err_lzma_end; |
| 87 | } |
| 88 | |
| 89 | strm.next_out = buf_out; |
| 90 | strm.avail_out = sizeof(buf_out); |
| 91 | } |
| 92 | |
| 93 | if (ret != LZMA_OK) { |
| 94 | if (ret == LZMA_STREAM_END) |
| 95 | break; |
| 96 | |
| 97 | pr_err("lzma: failed %s\n", lzma_strerror(ret)); |
| 98 | goto err_lzma_end; |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | err = 0; |
| 103 | err_lzma_end: |
| 104 | lzma_end(&strm); |
| 105 | err_fclose: |
| 106 | fclose(infile); |
| 107 | return err; |
| 108 | } |
| 109 | |
| 110 | bool lzma_is_compressed(const char *input) |
| 111 | { |
| 112 | int fd = open(input, O_RDONLY); |
| 113 | const uint8_t magic[6] = { 0xFD, '7', 'z', 'X', 'Z', 0x00 }; |
| 114 | char buf[6] = { 0 }; |
| 115 | ssize_t rc; |
| 116 | |
| 117 | if (fd < 0) |
| 118 | return -1; |
| 119 | |
| 120 | rc = read(fd, buf, sizeof(buf)); |
| 121 | close(fd); |
| 122 | return rc == sizeof(buf) ? |
| 123 | memcmp(buf, magic, sizeof(buf)) == 0 : false; |
| 124 | } |