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_debug("lzma: fopen failed on %s: '%s'\n" , input, strerror(errno)); |
49 | return -1; |
50 | } |
51 | |
52 | ret = lzma_stream_decoder(&strm, UINT64_MAX, LZMA_CONCATENATED); |
53 | if (ret != LZMA_OK) { |
54 | pr_debug("lzma: lzma_stream_decoder failed %s (%d)\n" , lzma_strerror(ret), ret); |
55 | goto err_fclose; |
56 | } |
57 | |
58 | strm.next_in = NULL; |
59 | strm.avail_in = 0; |
60 | strm.next_out = buf_out; |
61 | strm.avail_out = sizeof(buf_out); |
62 | |
63 | while (1) { |
64 | if (strm.avail_in == 0 && !feof(infile)) { |
65 | strm.next_in = buf_in; |
66 | strm.avail_in = fread(buf_in, 1, sizeof(buf_in), infile); |
67 | |
68 | if (ferror(infile)) { |
69 | pr_debug("lzma: read error: %s\n" , strerror(errno)); |
70 | goto err_lzma_end; |
71 | } |
72 | |
73 | if (feof(infile)) |
74 | action = LZMA_FINISH; |
75 | } |
76 | |
77 | ret = lzma_code(&strm, action); |
78 | |
79 | if (strm.avail_out == 0 || ret == LZMA_STREAM_END) { |
80 | ssize_t write_size = sizeof(buf_out) - strm.avail_out; |
81 | |
82 | if (writen(output_fd, buf_out, write_size) != write_size) { |
83 | pr_debug("lzma: write error: %s\n" , strerror(errno)); |
84 | goto err_lzma_end; |
85 | } |
86 | |
87 | strm.next_out = buf_out; |
88 | strm.avail_out = sizeof(buf_out); |
89 | } |
90 | |
91 | if (ret != LZMA_OK) { |
92 | if (ret == LZMA_STREAM_END) |
93 | break; |
94 | |
95 | pr_debug("lzma: failed %s\n" , lzma_strerror(ret)); |
96 | goto err_lzma_end; |
97 | } |
98 | } |
99 | |
100 | err = 0; |
101 | err_lzma_end: |
102 | lzma_end(&strm); |
103 | err_fclose: |
104 | fclose(infile); |
105 | return err; |
106 | } |
107 | |
108 | bool lzma_is_compressed(const char *input) |
109 | { |
110 | int fd = open(input, O_RDONLY); |
111 | const uint8_t magic[6] = { 0xFD, '7', 'z', 'X', 'Z', 0x00 }; |
112 | char buf[6] = { 0 }; |
113 | ssize_t rc; |
114 | |
115 | if (fd < 0) |
116 | return -1; |
117 | |
118 | rc = read(fd, buf, sizeof(buf)); |
119 | close(fd); |
120 | return rc == sizeof(buf) ? |
121 | memcmp(buf, magic, sizeof(buf)) == 0 : false; |
122 | } |
123 | |