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git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - lib/decompress_inflate.c
2 /* Pre-boot environment: included */
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
8 #include "zlib_inflate/inftrees.c"
9 #include "zlib_inflate/inffast.c"
10 #include "zlib_inflate/inflate.c"
13 /* initramfs et al: linked */
15 #include <linux/zutil.h>
17 #include "zlib_inflate/inftrees.h"
18 #include "zlib_inflate/inffast.h"
19 #include "zlib_inflate/inflate.h"
21 #include "zlib_inflate/infutil.h"
22 #include <linux/slab.h>
26 #include <linux/decompress/mm.h>
28 #define GZIP_IOBUF_SIZE (16*1024)
30 static int nofill(void *buffer
, unsigned int len
)
35 /* Included from initramfs et al code */
36 STATIC
int INIT
gunzip(unsigned char *buf
, int len
,
37 int(*fill
)(void*, unsigned int),
38 int(*flush
)(void*, unsigned int),
39 unsigned char *out_buf
,
41 void(*error_fn
)(char *x
)) {
43 struct z_stream_s
*strm
;
47 set_error_fn(error_fn
);
50 out_len
= 0x8000; /* 32 K */
51 out_buf
= malloc(out_len
);
53 out_len
= 0x7fffffff; /* no limit */
56 error("Out of memory while allocating output buffer");
63 zbuf
= malloc(GZIP_IOBUF_SIZE
);
67 error("Out of memory while allocating input buffer");
71 strm
= malloc(sizeof(*strm
));
73 error("Out of memory while allocating z_stream");
77 strm
->workspace
= malloc(flush
? zlib_inflate_workspacesize() :
78 sizeof(struct inflate_state
));
79 if (strm
->workspace
== NULL
) {
80 error("Out of memory while allocating workspace");
88 len
= fill(zbuf
, GZIP_IOBUF_SIZE
);
90 /* verify the gzip header */
92 zbuf
[0] != 0x1f || zbuf
[1] != 0x8b || zbuf
[2] != 0x08) {
95 error("Not a gzip file");
99 /* skip over gzip header (1f,8b,08... 10 bytes total +
100 * possible asciz filename)
102 strm
->next_in
= zbuf
+ 10;
103 /* skip over asciz filename */
105 while (strm
->next_in
[0])
109 strm
->avail_in
= len
- (strm
->next_in
- zbuf
);
111 strm
->next_out
= out_buf
;
112 strm
->avail_out
= out_len
;
114 rc
= zlib_inflateInit2(strm
, -MAX_WBITS
);
117 WS(strm
)->inflate_state
.wsize
= 0;
118 WS(strm
)->inflate_state
.window
= NULL
;
122 if (strm
->avail_in
== 0) {
123 /* TODO: handle case where both pos and fill are set */
124 len
= fill(zbuf
, GZIP_IOBUF_SIZE
);
130 strm
->next_in
= zbuf
;
131 strm
->avail_in
= len
;
133 rc
= zlib_inflate(strm
, 0);
135 /* Write any data generated */
136 if (flush
&& strm
->next_out
> out_buf
) {
137 int l
= strm
->next_out
- out_buf
;
138 if (l
!= flush(out_buf
, l
)) {
140 error("write error");
143 strm
->next_out
= out_buf
;
144 strm
->avail_out
= out_len
;
147 /* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
148 if (rc
== Z_STREAM_END
) {
151 } else if (rc
!= Z_OK
) {
152 error("uncompression error");
157 zlib_inflateEnd(strm
);
159 /* add + 8 to skip over trailer */
160 *pos
= strm
->next_in
- zbuf
+8;
163 free(strm
->workspace
);
173 return rc
; /* returns Z_OK (0) if successful */
176 #define decompress gunzip