tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifdef STATIC
2/* Pre-boot environment: included */
3
4/* prevent inclusion of _LINUX_KERNEL_H in pre-boot environment: lots
5 * errors about console_printk etc... on ARM */
6#define _LINUX_KERNEL_H
7
8#include "zlib_inflate/inftrees.c"
9#include "zlib_inflate/inffast.c"
10#include "zlib_inflate/inflate.c"
11
12#else /* STATIC */
13/* initramfs et al: linked */
14
15#include <linux/zutil.h>
16
17#include "zlib_inflate/inftrees.h"
18#include "zlib_inflate/inffast.h"
19#include "zlib_inflate/inflate.h"
20
21#include "zlib_inflate/infutil.h"
22#include <linux/decompress/inflate.h>
23
24#endif /* STATIC */
25
26#include <linux/decompress/mm.h>
27
28#define GZIP_IOBUF_SIZE (16*1024)
29
30static long INIT nofill(void *buffer, unsigned long len)
31{
32 return -1;
33}
34
35/* Included from initramfs et al code */
36STATIC int INIT gunzip(unsigned char *buf, long len,
37 long (*fill)(void*, unsigned long),
38 long (*flush)(void*, unsigned long),
39 unsigned char *out_buf,
40 long *pos,
41 void(*error)(char *x)) {
42 u8 *zbuf;
43 struct z_stream_s *strm;
44 int rc;
45 size_t out_len;
46
47 rc = -1;
48 if (flush) {
49 out_len = 0x8000; /* 32 K */
50 out_buf = malloc(out_len);
51 } else {
52 out_len = ((size_t)~0) - (size_t)out_buf; /* no limit */
53 }
54 if (!out_buf) {
55 error("Out of memory while allocating output buffer");
56 goto gunzip_nomem1;
57 }
58
59 if (buf)
60 zbuf = buf;
61 else {
62 zbuf = malloc(GZIP_IOBUF_SIZE);
63 len = 0;
64 }
65 if (!zbuf) {
66 error("Out of memory while allocating input buffer");
67 goto gunzip_nomem2;
68 }
69
70 strm = malloc(sizeof(*strm));
71 if (strm == NULL) {
72 error("Out of memory while allocating z_stream");
73 goto gunzip_nomem3;
74 }
75
76 strm->workspace = malloc(flush ? zlib_inflate_workspacesize() :
77 sizeof(struct inflate_state));
78 if (strm->workspace == NULL) {
79 error("Out of memory while allocating workspace");
80 goto gunzip_nomem4;
81 }
82
83 if (!fill)
84 fill = nofill;
85
86 if (len == 0)
87 len = fill(zbuf, GZIP_IOBUF_SIZE);
88
89 /* verify the gzip header */
90 if (len < 10 ||
91 zbuf[0] != 0x1f || zbuf[1] != 0x8b || zbuf[2] != 0x08) {
92 if (pos)
93 *pos = 0;
94 error("Not a gzip file");
95 goto gunzip_5;
96 }
97
98 /* skip over gzip header (1f,8b,08... 10 bytes total +
99 * possible asciz filename)
100 */
101 strm->next_in = zbuf + 10;
102 strm->avail_in = len - 10;
103 /* skip over asciz filename */
104 if (zbuf[3] & 0x8) {
105 do {
106 /*
107 * If the filename doesn't fit into the buffer,
108 * the file is very probably corrupt. Don't try
109 * to read more data.
110 */
111 if (strm->avail_in == 0) {
112 error("header error");
113 goto gunzip_5;
114 }
115 --strm->avail_in;
116 } while (*strm->next_in++);
117 }
118
119 strm->next_out = out_buf;
120 strm->avail_out = out_len;
121
122 rc = zlib_inflateInit2(strm, -MAX_WBITS);
123
124 if (!flush) {
125 WS(strm)->inflate_state.wsize = 0;
126 WS(strm)->inflate_state.window = NULL;
127 }
128
129 while (rc == Z_OK) {
130 if (strm->avail_in == 0) {
131 /* TODO: handle case where both pos and fill are set */
132 len = fill(zbuf, GZIP_IOBUF_SIZE);
133 if (len < 0) {
134 rc = -1;
135 error("read error");
136 break;
137 }
138 strm->next_in = zbuf;
139 strm->avail_in = len;
140 }
141 rc = zlib_inflate(strm, 0);
142
143 /* Write any data generated */
144 if (flush && strm->next_out > out_buf) {
145 long l = strm->next_out - out_buf;
146 if (l != flush(out_buf, l)) {
147 rc = -1;
148 error("write error");
149 break;
150 }
151 strm->next_out = out_buf;
152 strm->avail_out = out_len;
153 }
154
155 /* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
156 if (rc == Z_STREAM_END) {
157 rc = 0;
158 break;
159 } else if (rc != Z_OK) {
160 error("uncompression error");
161 rc = -1;
162 }
163 }
164
165 zlib_inflateEnd(strm);
166 if (pos)
167 /* add + 8 to skip over trailer */
168 *pos = strm->next_in - zbuf+8;
169
170gunzip_5:
171 free(strm->workspace);
172gunzip_nomem4:
173 free(strm);
174gunzip_nomem3:
175 if (!buf)
176 free(zbuf);
177gunzip_nomem2:
178 if (flush)
179 free(out_buf);
180gunzip_nomem1:
181 return rc; /* returns Z_OK (0) if successful */
182}
183
184#define decompress gunzip