1#include <lzma.h>
2#include <stdio.h>
3#include <linux/compiler.h>
4#include "util.h"
5#include "debug.h"
6
7#define BUFSIZE 8192
8
9static const char *lzma_strerror(lzma_ret ret)
10{
11	switch ((int) ret) {
12	case LZMA_MEM_ERROR:
13		return "Memory allocation failed";
14	case LZMA_OPTIONS_ERROR:
15		return "Unsupported decompressor flags";
16	case LZMA_FORMAT_ERROR:
17		return "The input is not in the .xz format";
18	case LZMA_DATA_ERROR:
19		return "Compressed file is corrupt";
20	case LZMA_BUF_ERROR:
21		return "Compressed file is truncated or otherwise corrupt";
22	default:
23		return "Unknown error, possibly a bug";
24	}
25}
26
27int lzma_decompress_to_file(const char *input, int output_fd)
28{
29	lzma_action action = LZMA_RUN;
30	lzma_stream strm   = LZMA_STREAM_INIT;
31	lzma_ret ret;
32
33	u8 buf_in[BUFSIZE];
34	u8 buf_out[BUFSIZE];
35	FILE *infile;
36
37	infile = fopen(input, "rb");
38	if (!infile) {
39		pr_err("lzma: fopen failed on %s: '%s'\n",
40		       input, strerror(errno));
41		return -1;
42	}
43
44	ret = lzma_stream_decoder(&strm, UINT64_MAX, LZMA_CONCATENATED);
45	if (ret != LZMA_OK) {
46		pr_err("lzma: lzma_stream_decoder failed %s (%d)\n",
47			lzma_strerror(ret), ret);
48		return -1;
49	}
50
51	strm.next_in   = NULL;
52	strm.avail_in  = 0;
53	strm.next_out  = buf_out;
54	strm.avail_out = sizeof(buf_out);
55
56	while (1) {
57		if (strm.avail_in == 0 && !feof(infile)) {
58			strm.next_in  = buf_in;
59			strm.avail_in = fread(buf_in, 1, sizeof(buf_in), infile);
60
61			if (ferror(infile)) {
62				pr_err("lzma: read error: %s\n", strerror(errno));
63				return -1;
64			}
65
66			if (feof(infile))
67				action = LZMA_FINISH;
68		}
69
70		ret = lzma_code(&strm, action);
71
72		if (strm.avail_out == 0 || ret == LZMA_STREAM_END) {
73			ssize_t write_size = sizeof(buf_out) - strm.avail_out;
74
75			if (writen(output_fd, buf_out, write_size) != write_size) {
76				pr_err("lzma: write error: %s\n", strerror(errno));
77				return -1;
78			}
79
80			strm.next_out  = buf_out;
81			strm.avail_out = sizeof(buf_out);
82		}
83
84		if (ret != LZMA_OK) {
85			if (ret == LZMA_STREAM_END)
86				return 0;
87
88			pr_err("lzma: failed %s\n", lzma_strerror(ret));
89			return -1;
90		}
91	}
92
93	fclose(infile);
94	return 0;
95}
96