Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
c23c2a0f | 2 | #include <fcntl.h> |
e92ce12e | 3 | #include <stdio.h> |
8520a98d | 4 | #include <string.h> |
e92ce12e NK |
5 | #include <unistd.h> |
6 | #include <sys/stat.h> | |
7 | #include <sys/mman.h> | |
8 | #include <zlib.h> | |
8b42b7e5 | 9 | #include <linux/compiler.h> |
fb71c86c | 10 | #include <internal/lib.h> |
e92ce12e | 11 | |
611f0afe | 12 | #include "util/compress.h" |
e92ce12e NK |
13 | |
14 | #define CHUNK_SIZE 16384 | |
15 | ||
16 | int gzip_decompress_to_file(const char *input, int output_fd) | |
17 | { | |
18 | int ret = Z_STREAM_ERROR; | |
19 | int input_fd; | |
20 | void *ptr; | |
21 | int len; | |
22 | struct stat stbuf; | |
23 | unsigned char buf[CHUNK_SIZE]; | |
24 | z_stream zs = { | |
25 | .zalloc = Z_NULL, | |
26 | .zfree = Z_NULL, | |
27 | .opaque = Z_NULL, | |
28 | .avail_in = 0, | |
29 | .next_in = Z_NULL, | |
30 | }; | |
31 | ||
32 | input_fd = open(input, O_RDONLY); | |
33 | if (input_fd < 0) | |
34 | return -1; | |
35 | ||
36 | if (fstat(input_fd, &stbuf) < 0) | |
37 | goto out_close; | |
38 | ||
39 | ptr = mmap(NULL, stbuf.st_size, PROT_READ, MAP_PRIVATE, input_fd, 0); | |
40 | if (ptr == MAP_FAILED) | |
41 | goto out_close; | |
42 | ||
43 | if (inflateInit2(&zs, 16 + MAX_WBITS) != Z_OK) | |
44 | goto out_unmap; | |
45 | ||
46 | zs.next_in = ptr; | |
47 | zs.avail_in = stbuf.st_size; | |
48 | ||
49 | do { | |
50 | zs.next_out = buf; | |
51 | zs.avail_out = CHUNK_SIZE; | |
52 | ||
53 | ret = inflate(&zs, Z_NO_FLUSH); | |
54 | switch (ret) { | |
55 | case Z_NEED_DICT: | |
56 | ret = Z_DATA_ERROR; | |
57 | /* fall through */ | |
58 | case Z_DATA_ERROR: | |
59 | case Z_MEM_ERROR: | |
60 | goto out; | |
61 | default: | |
62 | break; | |
63 | } | |
64 | ||
65 | len = CHUNK_SIZE - zs.avail_out; | |
66 | if (writen(output_fd, buf, len) != len) { | |
67 | ret = Z_DATA_ERROR; | |
68 | goto out; | |
69 | } | |
70 | ||
71 | } while (ret != Z_STREAM_END); | |
72 | ||
73 | out: | |
74 | inflateEnd(&zs); | |
75 | out_unmap: | |
76 | munmap(ptr, stbuf.st_size); | |
77 | out_close: | |
78 | close(input_fd); | |
79 | ||
80 | return ret == Z_STREAM_END ? 0 : -1; | |
81 | } | |
8b42b7e5 | 82 | |
88c74dc7 | 83 | bool gzip_is_compressed(const char *input) |
8b42b7e5 | 84 | { |
88c74dc7 JO |
85 | int fd = open(input, O_RDONLY); |
86 | const uint8_t magic[2] = { 0x1f, 0x8b }; | |
87 | char buf[2] = { 0 }; | |
88 | ssize_t rc; | |
89 | ||
90 | if (fd < 0) | |
91 | return -1; | |
92 | ||
93 | rc = read(fd, buf, sizeof(buf)); | |
94 | close(fd); | |
95 | return rc == sizeof(buf) ? | |
96 | memcmp(buf, magic, sizeof(buf)) == 0 : false; | |
8b42b7e5 | 97 | } |