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zlib 0.9

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This commit is contained in:
Mark Adler
2011-09-09 23:06:52 -07:00
parent 4ca984fb44
commit 64b2e89203
23 changed files with 783 additions and 200 deletions
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inflate.c
+139 -83
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@@ -15,38 +15,63 @@ struct internal_state {
enum {
METHOD, /* waiting for method byte */
FLAG, /* waiting for flag byte */
START, /* make new blocks state */
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 */
INF_ERROR}/* got an error--stay here */
BAD} /* got an error--stay here */
mode; /* current inflate mode */
/* mode dependent information */
union {
uInt method; /* if FLAGS, method byte */
struct inflate_blocks_state
*blocks; /* if BLOCKS, current state */
struct {
uLong was; /* computed check value */
uLong need; /* stream check value */
} check; /* if CHECK, check values to compare */
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) */
struct inflate_blocks_state
*blocks; /* current inflate_blocks state */
};
int inflateInit(z)
int inflateReset(z)
z_stream *z;
{
return inflateInit2(z, WBITS);
uLong c;
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, &c);
Trace((stderr, "inflate: reset\n"));
return Z_OK;
}
int inflateEnd(z)
z_stream *z;
{
uLong c;
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, &c);
ZFREE(z, z->state);
z->state = Z_NULL;
Trace((stderr, "inflate: end\n"));
return Z_OK;
}
@@ -59,12 +84,10 @@ int w;
return Z_STREAM_ERROR;
if (z->zalloc == Z_NULL) z->zalloc = zcalloc;
if (z->zfree == Z_NULL) z->zfree = zcfree;
z->total_in = z->total_out = 0;
z->msg = Z_NULL;
if ((z->state = (struct internal_state *)
ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
return Z_MEM_ERROR;
z->state->mode = METHOD;
z->state->blocks = Z_NULL;
/* handle undocumented nowrap option (no zlib header or check) */
z->state->nowrap = 0;
@@ -72,7 +95,6 @@ int w;
{
w = - w;
z->state->nowrap = 1;
z->state->mode = START;
}
/* set window size */
@@ -81,20 +103,40 @@ int w;
inflateEnd(z);
return Z_STREAM_ERROR;
}
z->state->wbits = w;
z->state->wbits = (uInt)w;
/* create inflate_blocks state */
if ((z->state->blocks =
inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w))
== Z_NULL)
{
inflateEnd(z);
return Z_MEM_ERROR;
}
Trace((stderr, "inflate: allocated\n"));
/* reset state */
inflateReset(z);
return Z_OK;
}
int inflateInit(z)
z_stream *z;
{
return inflateInit2(z, DEF_WBITS);
}
#define NEEDBYTE {if(z->avail_in==0)return r;r=Z_OK;}
#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
int inflate(z, f)
z_stream *z;
int f;
{
int r = f; /* to avoid warning about unused f */
int r = f; /* to avoid warning about unused f */
uInt b;
uLong c;
if (z == Z_NULL || z->next_in == Z_NULL)
return Z_STREAM_ERROR;
@@ -102,77 +144,86 @@ int f;
while (1) switch (z->state->mode)
{
case METHOD:
if (z->avail_in == 0) return r; r = Z_OK;
NEEDBYTE
if (((z->state->sub.method = NEXTBYTE) & 0xf != DEFLATED))
{
z->state->mode = INF_ERROR;
z->state->mode = BAD;
z->msg = "unknown compression method";
return Z_DATA_ERROR;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
{
z->state->mode = INF_ERROR;
z->state->mode = BAD;
z->msg = "invalid window size";
return Z_DATA_ERROR;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
z->state->mode = FLAG;
case FLAG:
if (z->avail_in == 0) return r; r = Z_OK;
NEEDBYTE
if ((b = NEXTBYTE) & 0x20)
{
z->state->mode = INF_ERROR;
z->state->mode = BAD;
z->msg = "invalid reserved bit";
return Z_DATA_ERROR;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
if (((z->state->sub.method << 8) + b) % 31)
{
z->state->mode = INF_ERROR;
z->state->mode = BAD;
z->msg = "incorrect header check";
return Z_DATA_ERROR;
}
z->state->mode = START;
case START:
if ((z->state->sub.blocks = inflate_blocks_new(z,
z->state->nowrap ? Z_NULL : adler32,
1<< z->state->wbits)) == Z_NULL)
return Z_MEM_ERROR;
z->state->mode = BLOCKS;
case BLOCKS:
if ((r = inflate_blocks(z->state->sub.blocks, z, r)) != Z_STREAM_END)
return r;
inflate_blocks_free(z->state->sub.blocks, z, &c);
if (z->state->nowrap)
{
z->state->mode = DONE;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
Trace((stderr, "inflate: zlib header ok\n"));
z->state->mode = BLOCKS;
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_STREAM_END)
return r;
r = Z_OK;
inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
if (z->state->nowrap)
{
z->state->mode = DONE;
break;
}
z->state->sub.check.was = c;
z->state->mode = CHECK4;
case CHECK4:
if (z->avail_in == 0) return r; r = Z_OK;
NEEDBYTE
z->state->sub.check.need = (uLong)NEXTBYTE << 24;
z->state->mode = CHECK3;
case CHECK3:
if (z->avail_in == 0) return r; r = Z_OK;
NEEDBYTE
z->state->sub.check.need += (uLong)NEXTBYTE << 16;
z->state->mode = CHECK2;
case CHECK2:
if (z->avail_in == 0) return r; r = Z_OK;
NEEDBYTE
z->state->sub.check.need += (uLong)NEXTBYTE << 8;
z->state->mode = CHECK1;
case CHECK1:
if (z->avail_in == 0) return r; r = Z_OK;
NEEDBYTE
z->state->sub.check.need += (uLong)NEXTBYTE;
if (z->state->sub.check.was != z->state->sub.check.need)
{
z->state->mode = INF_ERROR;
z->state->mode = BAD;
z->msg = "incorrect data check";
return Z_DATA_ERROR;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
Trace((stderr, "inflate: zlib check ok\n"));
z->state->mode = DONE;
case DONE:
return Z_STREAM_END;
case INF_ERROR:
case BAD:
return Z_DATA_ERROR;
default:
return Z_STREAM_ERROR;
@@ -180,41 +231,46 @@ int f;
}
int inflateEnd(z)
z_stream *z;
{
uLong c;
if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
return Z_STREAM_ERROR;
if (z->state->mode == BLOCKS)
inflate_blocks_free(z->state->sub.blocks, z, &c);
ZFREE(z, z->state);
z->state = Z_NULL;
return Z_OK;
}
/* inflateSync not implemented yet--this just consumes input */
int inflateSync(z)
z_stream *z;
{
if (z == Z_NULL) return Z_STREAM_ERROR;
if (z->avail_in == 0) return Z_BUF_ERROR;
do {
z->total_in++;
} while (--z->avail_in);
return Z_DATA_ERROR;
}
/* inflateReset not fully implemented yet--this frees and reallocates */
int inflateReset(z)
z_stream *z;
{
int r;
if ((r = inflateEnd(z)) != Z_OK)
return r;
return inflateInit(z);
uInt n; /* number of bytes to look at */
Byte *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->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)
{
if (*p == (m < 2 ? 0 : 0xff))
m++;
else if (*p || m > 2)
m = 0;
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;
}