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	int err = -1;
33
34	u8 buf_in[BUFSIZE];
35	u8 buf_out[BUFSIZE];
36	FILE *infile;
37
38	infile = fopen(input, "rb");
39	if (!infile) {
40		pr_err("lzma: fopen failed on %s: '%s'\n",
41		       input, strerror(errno));
42		return -1;
43	}
44
45	ret = lzma_stream_decoder(&strm, UINT64_MAX, LZMA_CONCATENATED);
46	if (ret != LZMA_OK) {
47		pr_err("lzma: lzma_stream_decoder failed %s (%d)\n",
48			lzma_strerror(ret), ret);
49		goto err_fclose;
50	}
51
52	strm.next_in   = NULL;
53	strm.avail_in  = 0;
54	strm.next_out  = buf_out;
55	strm.avail_out = sizeof(buf_out);
56
57	while (1) {
58		if (strm.avail_in == 0 && !feof(infile)) {
59			strm.next_in  = buf_in;
60			strm.avail_in = fread(buf_in, 1, sizeof(buf_in), infile);
61
62			if (ferror(infile)) {
63				pr_err("lzma: read error: %s\n", strerror(errno));
64				goto err_fclose;
65			}
66
67			if (feof(infile))
68				action = LZMA_FINISH;
69		}
70
71		ret = lzma_code(&strm, action);
72
73		if (strm.avail_out == 0 || ret == LZMA_STREAM_END) {
74			ssize_t write_size = sizeof(buf_out) - strm.avail_out;
75
76			if (writen(output_fd, buf_out, write_size) != write_size) {
77				pr_err("lzma: write error: %s\n", strerror(errno));
78				goto err_fclose;
79			}
80
81			strm.next_out  = buf_out;
82			strm.avail_out = sizeof(buf_out);
83		}
84
85		if (ret != LZMA_OK) {
86			if (ret == LZMA_STREAM_END)
87				break;
88
89			pr_err("lzma: failed %s\n", lzma_strerror(ret));
90			goto err_fclose;
91		}
92	}
93
94	err = 0;
95err_fclose:
96	fclose(infile);
97	return err;
98}