mirror of
https://gcc.gnu.org/git/gcc.git
synced 2024-12-05 01:34:12 +08:00
367 lines
9.4 KiB
C
367 lines
9.4 KiB
C
/* inflate.c -- zlib interface to inflate modules
|
|
* Copyright (C) 1995-1998 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
#include "zutil.h"
|
|
#include "infblock.h"
|
|
|
|
struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
|
|
|
|
typedef enum {
|
|
METHOD, /* waiting for method byte */
|
|
FLAG, /* waiting for flag byte */
|
|
DICT4, /* four dictionary check bytes to go */
|
|
DICT3, /* three dictionary check bytes to go */
|
|
DICT2, /* two dictionary check bytes to go */
|
|
DICT1, /* one dictionary check byte to go */
|
|
DICT0, /* waiting for inflateSetDictionary */
|
|
BLOCKS, /* decompressing blocks */
|
|
CHECK4, /* four check bytes to go */
|
|
CHECK3, /* three check bytes to go */
|
|
CHECK2, /* two check bytes to go */
|
|
CHECK1, /* one check byte to go */
|
|
DONE, /* finished check, done */
|
|
BAD} /* got an error--stay here */
|
|
inflate_mode;
|
|
|
|
/* inflate private state */
|
|
struct internal_state {
|
|
|
|
/* mode */
|
|
inflate_mode mode; /* current inflate mode */
|
|
|
|
/* mode dependent information */
|
|
union {
|
|
uInt method; /* if FLAGS, method byte */
|
|
struct {
|
|
uLong was; /* computed check value */
|
|
uLong need; /* stream check value */
|
|
} check; /* if CHECK, check values to compare */
|
|
uInt marker; /* if BAD, inflateSync's marker bytes count */
|
|
} sub; /* submode */
|
|
|
|
/* mode independent information */
|
|
int nowrap; /* flag for no wrapper */
|
|
uInt wbits; /* log2(window size) (8..15, defaults to 15) */
|
|
inflate_blocks_statef
|
|
*blocks; /* current inflate_blocks state */
|
|
|
|
};
|
|
|
|
|
|
int ZEXPORT inflateReset(z)
|
|
z_streamp z;
|
|
{
|
|
if (z == Z_NULL || z->state == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
z->total_in = z->total_out = 0;
|
|
z->msg = Z_NULL;
|
|
z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
|
|
inflate_blocks_reset(z->state->blocks, z, Z_NULL);
|
|
Tracev((stderr, "inflate: reset\n"));
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
int ZEXPORT inflateEnd(z)
|
|
z_streamp z;
|
|
{
|
|
if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
if (z->state->blocks != Z_NULL)
|
|
inflate_blocks_free(z->state->blocks, z);
|
|
ZFREE(z, z->state);
|
|
z->state = Z_NULL;
|
|
Tracev((stderr, "inflate: end\n"));
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
int ZEXPORT inflateInit2_(z, w, version, stream_size)
|
|
z_streamp z;
|
|
int w;
|
|
const char *version;
|
|
int stream_size;
|
|
{
|
|
if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
|
|
stream_size != sizeof(z_stream))
|
|
return Z_VERSION_ERROR;
|
|
|
|
/* initialize state */
|
|
if (z == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
z->msg = Z_NULL;
|
|
if (z->zalloc == Z_NULL)
|
|
{
|
|
z->zalloc = zcalloc;
|
|
z->opaque = (voidpf)0;
|
|
}
|
|
if (z->zfree == Z_NULL) z->zfree = zcfree;
|
|
if ((z->state = (struct internal_state FAR *)
|
|
ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
|
|
return Z_MEM_ERROR;
|
|
z->state->blocks = Z_NULL;
|
|
|
|
/* handle undocumented nowrap option (no zlib header or check) */
|
|
z->state->nowrap = 0;
|
|
if (w < 0)
|
|
{
|
|
w = - w;
|
|
z->state->nowrap = 1;
|
|
}
|
|
|
|
/* set window size */
|
|
if (w < 8 || w > 15)
|
|
{
|
|
inflateEnd(z);
|
|
return Z_STREAM_ERROR;
|
|
}
|
|
z->state->wbits = (uInt)w;
|
|
|
|
/* create inflate_blocks state */
|
|
if ((z->state->blocks =
|
|
inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
|
|
== Z_NULL)
|
|
{
|
|
inflateEnd(z);
|
|
return Z_MEM_ERROR;
|
|
}
|
|
Tracev((stderr, "inflate: allocated\n"));
|
|
|
|
/* reset state */
|
|
inflateReset(z);
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
int ZEXPORT inflateInit_(z, version, stream_size)
|
|
z_streamp z;
|
|
const char *version;
|
|
int stream_size;
|
|
{
|
|
return inflateInit2_(z, DEF_WBITS, version, stream_size);
|
|
}
|
|
|
|
|
|
#define NEEDBYTE {if(z->avail_in==0)return r;r=f;}
|
|
#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
|
|
|
|
int ZEXPORT inflate(z, f)
|
|
z_streamp z;
|
|
int f;
|
|
{
|
|
int r;
|
|
uInt b;
|
|
|
|
if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
f = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
|
|
r = Z_BUF_ERROR;
|
|
while (1) switch (z->state->mode)
|
|
{
|
|
case METHOD:
|
|
NEEDBYTE
|
|
if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = (char*)"unknown compression method";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = (char*)"invalid window size";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
z->state->mode = FLAG;
|
|
case FLAG:
|
|
NEEDBYTE
|
|
b = NEXTBYTE;
|
|
if (((z->state->sub.method << 8) + b) % 31)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = (char*)"incorrect header check";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
Tracev((stderr, "inflate: zlib header ok\n"));
|
|
if (!(b & PRESET_DICT))
|
|
{
|
|
z->state->mode = BLOCKS;
|
|
break;
|
|
}
|
|
z->state->mode = DICT4;
|
|
case DICT4:
|
|
NEEDBYTE
|
|
z->state->sub.check.need = (uLong)NEXTBYTE << 24;
|
|
z->state->mode = DICT3;
|
|
case DICT3:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE << 16;
|
|
z->state->mode = DICT2;
|
|
case DICT2:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE << 8;
|
|
z->state->mode = DICT1;
|
|
case DICT1:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE;
|
|
z->adler = z->state->sub.check.need;
|
|
z->state->mode = DICT0;
|
|
return Z_NEED_DICT;
|
|
case DICT0:
|
|
z->state->mode = BAD;
|
|
z->msg = (char*)"need dictionary";
|
|
z->state->sub.marker = 0; /* can try inflateSync */
|
|
return Z_STREAM_ERROR;
|
|
case BLOCKS:
|
|
r = inflate_blocks(z->state->blocks, z, r);
|
|
if (r == Z_DATA_ERROR)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->state->sub.marker = 0; /* can try inflateSync */
|
|
break;
|
|
}
|
|
if (r == Z_OK)
|
|
r = f;
|
|
if (r != Z_STREAM_END)
|
|
return r;
|
|
r = f;
|
|
inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
|
|
if (z->state->nowrap)
|
|
{
|
|
z->state->mode = DONE;
|
|
break;
|
|
}
|
|
z->state->mode = CHECK4;
|
|
case CHECK4:
|
|
NEEDBYTE
|
|
z->state->sub.check.need = (uLong)NEXTBYTE << 24;
|
|
z->state->mode = CHECK3;
|
|
case CHECK3:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE << 16;
|
|
z->state->mode = CHECK2;
|
|
case CHECK2:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE << 8;
|
|
z->state->mode = CHECK1;
|
|
case CHECK1:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE;
|
|
|
|
if (z->state->sub.check.was != z->state->sub.check.need)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = (char*)"incorrect data check";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
Tracev((stderr, "inflate: zlib check ok\n"));
|
|
z->state->mode = DONE;
|
|
case DONE:
|
|
return Z_STREAM_END;
|
|
case BAD:
|
|
return Z_DATA_ERROR;
|
|
default:
|
|
return Z_STREAM_ERROR;
|
|
}
|
|
#ifdef NEED_DUMMY_RETURN
|
|
return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
|
|
#endif
|
|
}
|
|
|
|
|
|
int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
|
|
z_streamp z;
|
|
const Bytef *dictionary;
|
|
uInt dictLength;
|
|
{
|
|
uInt length = dictLength;
|
|
|
|
if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
|
|
return Z_STREAM_ERROR;
|
|
|
|
if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
|
|
z->adler = 1L;
|
|
|
|
if (length >= ((uInt)1<<z->state->wbits))
|
|
{
|
|
length = (1<<z->state->wbits)-1;
|
|
dictionary += dictLength - length;
|
|
}
|
|
inflate_set_dictionary(z->state->blocks, dictionary, length);
|
|
z->state->mode = BLOCKS;
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
int ZEXPORT inflateSync(z)
|
|
z_streamp z;
|
|
{
|
|
uInt n; /* number of bytes to look at */
|
|
Bytef *p; /* pointer to bytes */
|
|
uInt m; /* number of marker bytes found in a row */
|
|
uLong r, w; /* temporaries to save total_in and total_out */
|
|
|
|
/* set up */
|
|
if (z == Z_NULL || z->state == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
if (z->state->mode != BAD)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->state->sub.marker = 0;
|
|
}
|
|
if ((n = z->avail_in) == 0)
|
|
return Z_BUF_ERROR;
|
|
p = z->next_in;
|
|
m = z->state->sub.marker;
|
|
|
|
/* search */
|
|
while (n && m < 4)
|
|
{
|
|
static const Byte mark[4] = {0, 0, 0xff, 0xff};
|
|
if (*p == mark[m])
|
|
m++;
|
|
else if (*p)
|
|
m = 0;
|
|
else
|
|
m = 4 - m;
|
|
p++, n--;
|
|
}
|
|
|
|
/* restore */
|
|
z->total_in += p - z->next_in;
|
|
z->next_in = p;
|
|
z->avail_in = n;
|
|
z->state->sub.marker = m;
|
|
|
|
/* return no joy or set up to restart on a new block */
|
|
if (m != 4)
|
|
return Z_DATA_ERROR;
|
|
r = z->total_in; w = z->total_out;
|
|
inflateReset(z);
|
|
z->total_in = r; z->total_out = w;
|
|
z->state->mode = BLOCKS;
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
/* Returns true if inflate is currently at the end of a block generated
|
|
* by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
|
|
* implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
|
|
* but removes the length bytes of the resulting empty stored block. When
|
|
* decompressing, PPP checks that at the end of input packet, inflate is
|
|
* waiting for these length bytes.
|
|
*/
|
|
int ZEXPORT inflateSyncPoint(z)
|
|
z_streamp z;
|
|
{
|
|
if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
return inflate_blocks_sync_point(z->state->blocks);
|
|
}
|