Commit | Line | Data |
---|---|---|
e92ce12e NK |
1 | #include <stdio.h> |
2 | #include <unistd.h> | |
3 | #include <sys/stat.h> | |
4 | #include <sys/mman.h> | |
5 | #include <zlib.h> | |
6 | ||
7 | #include "util/util.h" | |
8 | #include "util/debug.h" | |
9 | ||
10 | ||
11 | #define CHUNK_SIZE 16384 | |
12 | ||
13 | int gzip_decompress_to_file(const char *input, int output_fd) | |
14 | { | |
15 | int ret = Z_STREAM_ERROR; | |
16 | int input_fd; | |
17 | void *ptr; | |
18 | int len; | |
19 | struct stat stbuf; | |
20 | unsigned char buf[CHUNK_SIZE]; | |
21 | z_stream zs = { | |
22 | .zalloc = Z_NULL, | |
23 | .zfree = Z_NULL, | |
24 | .opaque = Z_NULL, | |
25 | .avail_in = 0, | |
26 | .next_in = Z_NULL, | |
27 | }; | |
28 | ||
29 | input_fd = open(input, O_RDONLY); | |
30 | if (input_fd < 0) | |
31 | return -1; | |
32 | ||
33 | if (fstat(input_fd, &stbuf) < 0) | |
34 | goto out_close; | |
35 | ||
36 | ptr = mmap(NULL, stbuf.st_size, PROT_READ, MAP_PRIVATE, input_fd, 0); | |
37 | if (ptr == MAP_FAILED) | |
38 | goto out_close; | |
39 | ||
40 | if (inflateInit2(&zs, 16 + MAX_WBITS) != Z_OK) | |
41 | goto out_unmap; | |
42 | ||
43 | zs.next_in = ptr; | |
44 | zs.avail_in = stbuf.st_size; | |
45 | ||
46 | do { | |
47 | zs.next_out = buf; | |
48 | zs.avail_out = CHUNK_SIZE; | |
49 | ||
50 | ret = inflate(&zs, Z_NO_FLUSH); | |
51 | switch (ret) { | |
52 | case Z_NEED_DICT: | |
53 | ret = Z_DATA_ERROR; | |
54 | /* fall through */ | |
55 | case Z_DATA_ERROR: | |
56 | case Z_MEM_ERROR: | |
57 | goto out; | |
58 | default: | |
59 | break; | |
60 | } | |
61 | ||
62 | len = CHUNK_SIZE - zs.avail_out; | |
63 | if (writen(output_fd, buf, len) != len) { | |
64 | ret = Z_DATA_ERROR; | |
65 | goto out; | |
66 | } | |
67 | ||
68 | } while (ret != Z_STREAM_END); | |
69 | ||
70 | out: | |
71 | inflateEnd(&zs); | |
72 | out_unmap: | |
73 | munmap(ptr, stbuf.st_size); | |
74 | out_close: | |
75 | close(input_fd); | |
76 | ||
77 | return ret == Z_STREAM_END ? 0 : -1; | |
78 | } |