bzip2/lzma: library support for gzip, bzip2 and lzma decompression
Impact: Replaces inflate.c with a wrapper around zlib_inflate; new library code This is the first part of the bzip2/lzma patch The bzip patch is based on an idea by Christian Ludwig, includes support for compressing the kernel with bzip2 or lzma rather than gzip. Both compressors give smaller sizes than gzip. Lzma's decompresses faster than bzip2. It also supports ramdisks and initramfs' compressed using these two compressors. The functionality has been successfully used for a couple of years by the udpcast project This version applies to "tip" kernel 2.6.28 This part contains: - changed inflate.c to accomodate rest of patch - implementation of bzip2 compression (not used at this stage yet) - implementation of lzma compression (not used at this stage yet) - Makefile routines to support bzip2 and lzma kernel compression Signed-off-by: Alain Knaff <alain@knaff.lu> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Alain Knaff
committed by
H. Peter Anvin
H. Peter Anvin
parent
7d3b56ba37
commit
bc22c17e12
167
lib/decompress_inflate.c
Normal file
167
lib/decompress_inflate.c
Normal file
@@ -0,0 +1,167 @@
|
||||
#ifdef STATIC
|
||||
/* Pre-boot environment: included */
|
||||
|
||||
/* prevent inclusion of _LINUX_KERNEL_H in pre-boot environment: lots
|
||||
* errors about console_printk etc... on ARM */
|
||||
#define _LINUX_KERNEL_H
|
||||
|
||||
#include "zlib_inflate/inftrees.c"
|
||||
#include "zlib_inflate/inffast.c"
|
||||
#include "zlib_inflate/inflate.c"
|
||||
|
||||
#else /* STATIC */
|
||||
/* initramfs et al: linked */
|
||||
|
||||
#include <linux/zutil.h>
|
||||
|
||||
#include "zlib_inflate/inftrees.h"
|
||||
#include "zlib_inflate/inffast.h"
|
||||
#include "zlib_inflate/inflate.h"
|
||||
|
||||
#include "zlib_inflate/infutil.h"
|
||||
|
||||
#endif /* STATIC */
|
||||
|
||||
#include <linux/decompress/mm.h>
|
||||
|
||||
#define INBUF_LEN (16*1024)
|
||||
|
||||
/* Included from initramfs et al code */
|
||||
STATIC int INIT gunzip(unsigned char *buf, int len,
|
||||
int(*fill)(void*, unsigned int),
|
||||
int(*flush)(void*, unsigned int),
|
||||
unsigned char *out_buf,
|
||||
int *pos,
|
||||
void(*error_fn)(char *x)) {
|
||||
u8 *zbuf;
|
||||
struct z_stream_s *strm;
|
||||
int rc;
|
||||
size_t out_len;
|
||||
|
||||
set_error_fn(error_fn);
|
||||
rc = -1;
|
||||
if (flush) {
|
||||
out_len = 0x8100; /* 32 K */
|
||||
out_buf = malloc(out_len);
|
||||
} else {
|
||||
out_len = 0x7fffffff; /* no limit */
|
||||
}
|
||||
if (!out_buf) {
|
||||
error("Out of memory while allocating output buffer");
|
||||
goto gunzip_nomem1;
|
||||
}
|
||||
|
||||
if (buf)
|
||||
zbuf = buf;
|
||||
else {
|
||||
zbuf = malloc(INBUF_LEN);
|
||||
len = 0;
|
||||
}
|
||||
if (!zbuf) {
|
||||
error("Out of memory while allocating input buffer");
|
||||
goto gunzip_nomem2;
|
||||
}
|
||||
|
||||
strm = malloc(sizeof(*strm));
|
||||
if (strm == NULL) {
|
||||
error("Out of memory while allocating z_stream");
|
||||
goto gunzip_nomem3;
|
||||
}
|
||||
|
||||
strm->workspace = malloc(flush ? zlib_inflate_workspacesize() :
|
||||
sizeof(struct inflate_state));
|
||||
if (strm->workspace == NULL) {
|
||||
error("Out of memory while allocating workspace");
|
||||
goto gunzip_nomem4;
|
||||
}
|
||||
|
||||
if (len == 0)
|
||||
len = fill(zbuf, INBUF_LEN);
|
||||
|
||||
/* verify the gzip header */
|
||||
if (len < 10 ||
|
||||
zbuf[0] != 0x1f || zbuf[1] != 0x8b || zbuf[2] != 0x08) {
|
||||
if (pos)
|
||||
*pos = 0;
|
||||
error("Not a gzip file");
|
||||
goto gunzip_5;
|
||||
}
|
||||
|
||||
/* skip over gzip header (1f,8b,08... 10 bytes total +
|
||||
* possible asciz filename)
|
||||
*/
|
||||
strm->next_in = zbuf + 10;
|
||||
/* skip over asciz filename */
|
||||
if (zbuf[3] & 0x8) {
|
||||
while (strm->next_in[0])
|
||||
strm->next_in++;
|
||||
strm->next_in++;
|
||||
}
|
||||
strm->avail_in = len - 10;
|
||||
|
||||
strm->next_out = out_buf;
|
||||
strm->avail_out = out_len;
|
||||
|
||||
rc = zlib_inflateInit2(strm, -MAX_WBITS);
|
||||
|
||||
if (!flush) {
|
||||
WS(strm)->inflate_state.wsize = 0;
|
||||
WS(strm)->inflate_state.window = NULL;
|
||||
}
|
||||
|
||||
while (rc == Z_OK) {
|
||||
if (strm->avail_in == 0) {
|
||||
/* TODO: handle case where both pos and fill are set */
|
||||
len = fill(zbuf, INBUF_LEN);
|
||||
if (len < 0) {
|
||||
rc = -1;
|
||||
error("read error");
|
||||
break;
|
||||
}
|
||||
strm->next_in = zbuf;
|
||||
strm->avail_in = len;
|
||||
}
|
||||
rc = zlib_inflate(strm, 0);
|
||||
|
||||
/* Write any data generated */
|
||||
if (flush && strm->next_out > out_buf) {
|
||||
int l = strm->next_out - out_buf;
|
||||
if (l != flush(out_buf, l)) {
|
||||
rc = -1;
|
||||
error("write error");
|
||||
break;
|
||||
}
|
||||
strm->next_out = out_buf;
|
||||
strm->avail_out = out_len;
|
||||
}
|
||||
|
||||
/* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
|
||||
if (rc == Z_STREAM_END) {
|
||||
rc = 0;
|
||||
break;
|
||||
} else if (rc != Z_OK) {
|
||||
error("uncompression error");
|
||||
rc = -1;
|
||||
}
|
||||
}
|
||||
|
||||
zlib_inflateEnd(strm);
|
||||
if (pos)
|
||||
/* add + 8 to skip over trailer */
|
||||
*pos = strm->next_in - zbuf+8;
|
||||
|
||||
gunzip_5:
|
||||
free(strm->workspace);
|
||||
gunzip_nomem4:
|
||||
free(strm);
|
||||
gunzip_nomem3:
|
||||
if (!buf)
|
||||
free(zbuf);
|
||||
gunzip_nomem2:
|
||||
if (flush)
|
||||
free(out_buf);
|
||||
gunzip_nomem1:
|
||||
return rc; /* returns Z_OK (0) if successful */
|
||||
}
|
||||
|
||||
#define decompress gunzip
|
||||
Reference in New Issue
Block a user