summaryrefslogtreecommitdiffstats
path: root/lib/zlib_inflate/inflate.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/zlib_inflate/inflate.c')
-rw-r--r--lib/zlib_inflate/inflate.c1086
1 files changed, 876 insertions, 210 deletions
diff --git a/lib/zlib_inflate/inflate.c b/lib/zlib_inflate/inflate.c
index 31b9e9054bf7..7f922dccf1a5 100644
--- a/lib/zlib_inflate/inflate.c
+++ b/lib/zlib_inflate/inflate.c
@@ -1,89 +1,148 @@
-/* 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
+/* inflate.c -- zlib decompression
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ *
+ * Based on zlib 1.2.3 but modified for the Linux Kernel by
+ * Richard Purdie <richard@openedhand.com>
+ *
+ * Changes mainly for static instead of dynamic memory allocation
+ *
*/
#include <linux/zutil.h>
-#include "infblock.h"
+#include "inftrees.h"
+#include "inflate.h"
+#include "inffast.h"
#include "infutil.h"
int zlib_inflate_workspacesize(void)
{
- return sizeof(struct inflate_workspace);
+ return sizeof(struct inflate_workspace);
}
+int zlib_inflateReset(z_streamp strm)
+{
+ struct inflate_state *state;
+
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ state = (struct inflate_state *)strm->state;
+ strm->total_in = strm->total_out = state->total = 0;
+ strm->msg = NULL;
+ strm->adler = 1; /* to support ill-conceived Java test suite */
+ state->mode = HEAD;
+ state->last = 0;
+ state->havedict = 0;
+ state->dmax = 32768U;
+ state->hold = 0;
+ state->bits = 0;
+ state->lencode = state->distcode = state->next = state->codes;
-int zlib_inflateReset(
- z_streamp z
-)
+ /* Initialise Window */
+ state->wsize = 1U << state->wbits;
+ state->write = 0;
+ state->whave = 0;
+
+ return Z_OK;
+}
+
+#if 0
+int zlib_inflatePrime(z_streamp strm, int bits, int value)
{
- if (z == NULL || z->state == NULL || z->workspace == NULL)
- return Z_STREAM_ERROR;
- z->total_in = z->total_out = 0;
- z->msg = NULL;
- z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
- zlib_inflate_blocks_reset(z->state->blocks, z, NULL);
- return Z_OK;
+ struct inflate_state *state;
+
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ state = (struct inflate_state *)strm->state;
+ if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
+ value &= (1L << bits) - 1;
+ state->hold += value << state->bits;
+ state->bits += bits;
+ return Z_OK;
}
+#endif
+
+int zlib_inflateInit2(z_streamp strm, int windowBits)
+{
+ struct inflate_state *state;
+
+ if (strm == NULL) return Z_STREAM_ERROR;
+ strm->msg = NULL; /* in case we return an error */
+
+ state = &WS(strm)->inflate_state;
+ strm->state = (struct internal_state *)state;
+
+ if (windowBits < 0) {
+ state->wrap = 0;
+ windowBits = -windowBits;
+ }
+ else {
+ state->wrap = (windowBits >> 4) + 1;
+ }
+ if (windowBits < 8 || windowBits > 15) {
+ return Z_STREAM_ERROR;
+ }
+ state->wbits = (unsigned)windowBits;
+ state->window = &WS(strm)->working_window[0];
+ return zlib_inflateReset(strm);
+}
-int zlib_inflateEnd(
- z_streamp z
-)
+/*
+ Return state with length and distance decoding tables and index sizes set to
+ fixed code decoding. This returns fixed tables from inffixed.h.
+ */
+static void zlib_fixedtables(struct inflate_state *state)
{
- if (z == NULL || z->state == NULL || z->workspace == NULL)
- return Z_STREAM_ERROR;
- if (z->state->blocks != NULL)
- zlib_inflate_blocks_free(z->state->blocks, z);
- z->state = NULL;
- return Z_OK;
+# include "inffixed.h"
+ state->lencode = lenfix;
+ state->lenbits = 9;
+ state->distcode = distfix;
+ state->distbits = 5;
}
-int zlib_inflateInit2_(
- z_streamp z,
- int w,
- const char *version,
- int stream_size
-)
+/*
+ Update the window with the last wsize (normally 32K) bytes written before
+ returning. This is only called when a window is already in use, or when
+ output has been written during this inflate call, but the end of the deflate
+ stream has not been reached yet. It is also called to window dictionary data
+ when a dictionary is loaded.
+
+ Providing output buffers larger than 32K to inflate() should provide a speed
+ advantage, since only the last 32K of output is copied to the sliding window
+ upon return from inflate(), and since all distances after the first 32K of
+ output will fall in the output data, making match copies simpler and faster.
+ The advantage may be dependent on the size of the processor's data caches.
+ */
+static void zlib_updatewindow(z_streamp strm, unsigned out)
{
- if (version == NULL || version[0] != ZLIB_VERSION[0] ||
- stream_size != sizeof(z_stream) || z->workspace == NULL)
- return Z_VERSION_ERROR;
-
- /* initialize state */
- z->msg = NULL;
- z->state = &WS(z)->internal_state;
- z->state->blocks = 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)
- {
- zlib_inflateEnd(z);
- return Z_STREAM_ERROR;
- }
- z->state->wbits = (uInt)w;
-
- /* create inflate_blocks state */
- if ((z->state->blocks =
- zlib_inflate_blocks_new(z, z->state->nowrap ? NULL : zlib_adler32, (uInt)1 << w))
- == NULL)
- {
- zlib_inflateEnd(z);
- return Z_MEM_ERROR;
- }
-
- /* reset state */
- zlib_inflateReset(z);
- return Z_OK;
+ struct inflate_state *state;
+ unsigned copy, dist;
+
+ state = (struct inflate_state *)strm->state;
+
+ /* copy state->wsize or less output bytes into the circular window */
+ copy = out - strm->avail_out;
+ if (copy >= state->wsize) {
+ memcpy(state->window, strm->next_out - state->wsize, state->wsize);
+ state->write = 0;
+ state->whave = state->wsize;
+ }
+ else {
+ dist = state->wsize - state->write;
+ if (dist > copy) dist = copy;
+ memcpy(state->window + state->write, strm->next_out - copy, dist);
+ copy -= dist;
+ if (copy) {
+ memcpy(state->window, strm->next_out - copy, copy);
+ state->write = copy;
+ state->whave = state->wsize;
+ }
+ else {
+ state->write += dist;
+ if (state->write == state->wsize) state->write = 0;
+ if (state->whave < state->wsize) state->whave += dist;
+ }
+ }
}
@@ -91,157 +150,764 @@ int zlib_inflateInit2_(
* At the end of a Deflate-compressed PPP packet, we expect to have seen
* a `stored' block type value but not the (zero) length bytes.
*/
-static int zlib_inflate_packet_flush(inflate_blocks_statef *s)
+/*
+ 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.
+ */
+static int zlib_inflateSyncPacket(z_streamp strm)
{
- if (s->mode != LENS)
- return Z_DATA_ERROR;
- s->mode = TYPE;
+ struct inflate_state *state;
+
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ state = (struct inflate_state *)strm->state;
+
+ if (state->mode == STORED && state->bits == 0) {
+ state->mode = TYPE;
+ return Z_OK;
+ }
+ return Z_DATA_ERROR;
+}
+
+/* Macros for inflate(): */
+
+/* check function to use adler32() for zlib or crc32() for gzip */
+#define UPDATE(check, buf, len) zlib_adler32(check, buf, len)
+
+/* Load registers with state in inflate() for speed */
+#define LOAD() \
+ do { \
+ put = strm->next_out; \
+ left = strm->avail_out; \
+ next = strm->next_in; \
+ have = strm->avail_in; \
+ hold = state->hold; \
+ bits = state->bits; \
+ } while (0)
+
+/* Restore state from registers in inflate() */
+#define RESTORE() \
+ do { \
+ strm->next_out = put; \
+ strm->avail_out = left; \
+ strm->next_in = next; \
+ strm->avail_in = have; \
+ state->hold = hold; \
+ state->bits = bits; \
+ } while (0)
+
+/* Clear the input bit accumulator */
+#define INITBITS() \
+ do { \
+ hold = 0; \
+ bits = 0; \
+ } while (0)
+
+/* Get a byte of input into the bit accumulator, or return from inflate()
+ if there is no input available. */
+#define PULLBYTE() \
+ do { \
+ if (have == 0) goto inf_leave; \
+ have--; \
+ hold += (unsigned long)(*next++) << bits; \
+ bits += 8; \
+ } while (0)
+
+/* Assure that there are at least n bits in the bit accumulator. If there is
+ not enough available input to do that, then return from inflate(). */
+#define NEEDBITS(n) \
+ do { \
+ while (bits < (unsigned)(n)) \
+ PULLBYTE(); \
+ } while (0)
+
+/* Return the low n bits of the bit accumulator (n < 16) */
+#define BITS(n) \
+ ((unsigned)hold & ((1U << (n)) - 1))
+
+/* Remove n bits from the bit accumulator */
+#define DROPBITS(n) \
+ do { \
+ hold >>= (n); \
+ bits -= (unsigned)(n); \
+ } while (0)
+
+/* Remove zero to seven bits as needed to go to a byte boundary */
+#define BYTEBITS() \
+ do { \
+ hold >>= bits & 7; \
+ bits -= bits & 7; \
+ } while (0)
+
+/* Reverse the bytes in a 32-bit value */
+#define REVERSE(q) \
+ ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
+ (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
+
+/*
+ inflate() uses a state machine to process as much input data and generate as
+ much output data as possible before returning. The state machine is
+ structured roughly as follows:
+
+ for (;;) switch (state) {
+ ...
+ case STATEn:
+ if (not enough input data or output space to make progress)
+ return;
+ ... make progress ...
+ state = STATEm;
+ break;
+ ...
+ }
+
+ so when inflate() is called again, the same case is attempted again, and
+ if the appropriate resources are provided, the machine proceeds to the
+ next state. The NEEDBITS() macro is usually the way the state evaluates
+ whether it can proceed or should return. NEEDBITS() does the return if
+ the requested bits are not available. The typical use of the BITS macros
+ is:
+
+ NEEDBITS(n);
+ ... do something with BITS(n) ...
+ DROPBITS(n);
+
+ where NEEDBITS(n) either returns from inflate() if there isn't enough
+ input left to load n bits into the accumulator, or it continues. BITS(n)
+ gives the low n bits in the accumulator. When done, DROPBITS(n) drops
+ the low n bits off the accumulator. INITBITS() clears the accumulator
+ and sets the number of available bits to zero. BYTEBITS() discards just
+ enough bits to put the accumulator on a byte boundary. After BYTEBITS()
+ and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
+
+ NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
+ if there is no input available. The decoding of variable length codes uses
+ PULLBYTE() directly in order to pull just enough bytes to decode the next
+ code, and no more.
+
+ Some states loop until they get enough input, making sure that enough
+ state information is maintained to continue the loop where it left off
+ if NEEDBITS() returns in the loop. For example, want, need, and keep
+ would all have to actually be part of the saved state in case NEEDBITS()
+ returns:
+
+ case STATEw:
+ while (want < need) {
+ NEEDBITS(n);
+ keep[want++] = BITS(n);
+ DROPBITS(n);
+ }
+ state = STATEx;
+ case STATEx:
+
+ As shown above, if the next state is also the next case, then the break
+ is omitted.
+
+ A state may also return if there is not enough output space available to
+ complete that state. Those states are copying stored data, writing a
+ literal byte, and copying a matching string.
+
+ When returning, a "goto inf_leave" is used to update the total counters,
+ update the check value, and determine whether any progress has been made
+ during that inflate() call in order to return the proper return code.
+ Progress is defined as a change in either strm->avail_in or strm->avail_out.
+ When there is a window, goto inf_leave will update the window with the last
+ output written. If a goto inf_leave occurs in the middle of decompression
+ and there is no window currently, goto inf_leave will create one and copy
+ output to the window for the next call of inflate().
+
+ In this implementation, the flush parameter of inflate() only affects the
+ return code (per zlib.h). inflate() always writes as much as possible to
+ strm->next_out, given the space available and the provided input--the effect
+ documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers
+ the allocation of and copying into a sliding window until necessary, which
+ provides the effect documented in zlib.h for Z_FINISH when the entire input
+ stream available. So the only thing the flush parameter actually does is:
+ when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it
+ will return Z_BUF_ERROR if it has not reached the end of the stream.
+ */
+
+int zlib_inflate(z_streamp strm, int flush)
+{
+ struct inflate_state *state;
+ unsigned char *next; /* next input */
+ unsigned char *put; /* next output */
+ unsigned have, left; /* available input and output */
+ unsigned long hold; /* bit buffer */
+ unsigned bits; /* bits in bit buffer */
+ unsigned in, out; /* save starting available input and output */
+ unsigned copy; /* number of stored or match bytes to copy */
+ unsigned char *from; /* where to copy match bytes from */
+ code this; /* current decoding table entry */
+ code last; /* parent table entry */
+ unsigned len; /* length to copy for repeats, bits to drop */
+ int ret; /* return code */
+ static const unsigned short order[19] = /* permutation of code lengths */
+ {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+
+ if (strm == NULL || strm->state == NULL || strm->next_out == NULL ||
+ (strm->next_in == NULL && strm->avail_in != 0))
+ return Z_STREAM_ERROR;
+
+ state = (struct inflate_state *)strm->state;
+
+ if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */
+ LOAD();
+ in = have;
+ out = left;
+ ret = Z_OK;
+ for (;;)
+ switch (state->mode) {
+ case HEAD:
+ if (state->wrap == 0) {
+ state->mode = TYPEDO;
+ break;
+ }
+ NEEDBITS(16);
+ if (
+ ((BITS(8) << 8) + (hold >> 8)) % 31) {
+ strm->msg = (char *)"incorrect header check";
+ state->mode = BAD;
+ break;
+ }
+ if (BITS(4) != Z_DEFLATED) {
+ strm->msg = (char *)"unknown compression method";
+ state->mode = BAD;
+ break;
+ }
+ DROPBITS(4);
+ len = BITS(4) + 8;
+ if (len > state->wbits) {
+ strm->msg = (char *)"invalid window size";
+ state->mode = BAD;
+ break;
+ }
+ state->dmax = 1U << len;
+ strm->adler = state->check = zlib_adler32(0L, NULL, 0);
+ state->mode = hold & 0x200 ? DICTID : TYPE;
+ INITBITS();
+ break;
+ case DICTID:
+ NEEDBITS(32);
+ strm->adler = state->check = REVERSE(hold);
+ INITBITS();
+ state->mode = DICT;
+ case DICT:
+ if (state->havedict == 0) {
+ RESTORE();
+ return Z_NEED_DICT;
+ }
+ strm->adler = state->check = zlib_adler32(0L, NULL, 0);
+ state->mode = TYPE;
+ case TYPE:
+ if (flush == Z_BLOCK) goto inf_leave;
+ case TYPEDO:
+ if (state->last) {
+ BYTEBITS();
+ state->mode = CHECK;
+ break;
+ }
+ NEEDBITS(3);
+ state->last = BITS(1);
+ DROPBITS(1);
+ switch (BITS(2)) {
+ case 0: /* stored block */
+ state->mode = STORED;
+ break;
+ case 1: /* fixed block */
+ zlib_fixedtables(state);
+ state->mode = LEN; /* decode codes */
+ break;
+ case 2: /* dynamic block */
+ state->mode = TABLE;
+ break;
+ case 3:
+ strm->msg = (char *)"invalid block type";
+ state->mode = BAD;
+ }
+ DROPBITS(2);
+ break;
+ case STORED:
+ BYTEBITS(); /* go to byte boundary */
+ NEEDBITS(32);
+ if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
+ strm->msg = (char *)"invalid stored block lengths";
+ state->mode = BAD;
+ break;
+ }
+ state->length = (unsigned)hold & 0xffff;
+ INITBITS();
+ state->mode = COPY;
+ case COPY:
+ copy = state->length;
+ if (copy) {
+ if (copy > have) copy = have;
+ if (copy > left) copy = left;
+ if (copy == 0) goto inf_leave;
+ memcpy(put, next, copy);
+ have -= copy;
+ next += copy;
+ left -= copy;
+ put += copy;
+ state->length -= copy;
+ break;
+ }
+ state->mode = TYPE;
+ break;
+ case TABLE:
+ NEEDBITS(14);
+ state->nlen = BITS(5) + 257;
+ DROPBITS(5);
+ state->ndist = BITS(5) + 1;
+ DROPBITS(5);
+ state->ncode = BITS(4) + 4;
+ DROPBITS(4);
+#ifndef PKZIP_BUG_WORKAROUND
+ if (state->nlen > 286 || state->ndist > 30) {
+ strm->msg = (char *)"too many length or distance symbols";
+ state->mode = BAD;
+ break;
+ }
+#endif
+ state->have = 0;
+ state->mode = LENLENS;
+ case LENLENS:
+ while (state->have < state->ncode) {
+ NEEDBITS(3);
+ state->lens[order[state->have++]] = (unsigned short)BITS(3);
+ DROPBITS(3);
+ }
+ while (state->have < 19)
+ state->lens[order[state->have++]] = 0;
+ state->next = state->codes;
+ state->lencode = (code const *)(state->next);
+ state->lenbits = 7;
+ ret = zlib_inflate_table(CODES, state->lens, 19, &(state->next),
+ &(state->lenbits), state->work);
+ if (ret) {
+ strm->msg = (char *)"invalid code lengths set";
+ state->mode = BAD;
+ break;
+ }
+ state->have = 0;
+ state->mode = CODELENS;
+ case CODELENS:
+ while (state->have < state->nlen + state->ndist) {
+ for (;;) {
+ this = state->lencode[BITS(state->lenbits)];
+ if ((unsigned)(this.bits) <= bits) break;
+ PULLBYTE();
+ }
+ if (this.val < 16) {
+ NEEDBITS(this.bits);
+ DROPBITS(this.bits);
+ state->lens[state->have++] = this.val;
+ }
+ else {
+ if (this.val == 16) {
+ NEEDBITS(this.bits + 2);
+ DROPBITS(this.bits);
+ if (state->have == 0) {
+ strm->msg = (char *)"invalid bit length repeat";
+ state->mode = BAD;
+ break;
+ }
+ len = state->lens[state->have - 1];
+ copy = 3 + BITS(2);
+ DROPBITS(2);
+ }
+ else if (this.val == 17) {
+ NEEDBITS(this.bits + 3);
+ DROPBITS(this.bits);
+ len = 0;
+ copy = 3 + BITS(3);
+ DROPBITS(3);
+ }
+ else {
+ NEEDBITS(this.bits + 7);
+ DROPBITS(this.bits);
+ len = 0;
+ copy = 11 + BITS(7);
+ DROPBITS(7);
+ }
+ if (state->have + copy > state->nlen + state->ndist) {
+ strm->msg = (char *)"invalid bit length repeat";
+ state->mode = BAD;
+ break;
+ }
+ while (copy--)
+ state->lens[state->have++] = (unsigned short)len;
+ }
+ }
+
+ /* handle error breaks in while */
+ if (state->mode == BAD) break;
+
+ /* build code tables */
+ state->next = state->codes;
+ state->lencode = (code const *)(state->next);
+ state->lenbits = 9;
+ ret = zlib_inflate_table(LENS, state->lens, state->nlen, &(state->next),
+ &(state->lenbits), state->work);
+ if (ret) {
+ strm->msg = (char *)"invalid literal/lengths set";
+ state->mode = BAD;
+ break;
+ }
+ state->distcode = (code const *)(state->next);
+ state->distbits = 6;
+ ret = zlib_inflate_table(DISTS, state->lens + state->nlen, state->ndist,
+ &(state->next), &(state->distbits), state->work);
+ if (ret) {
+ strm->msg = (char *)"invalid distances set";
+ state->mode = BAD;
+ break;
+ }
+ state->mode = LEN;
+ case LEN:
+ if (have >= 6 && left >= 258) {
+ RESTORE();
+ inflate_fast(strm, out);
+ LOAD();
+ break;
+ }
+ for (;;) {
+ this = state->lencode[BITS(state->lenbits)];
+ if ((unsigned)(this.bits) <= bits) break;
+ PULLBYTE();
+ }
+ if (this.op && (this.op & 0xf0) == 0) {
+ last = this;
+ for (;;) {
+ this = state->lencode[last.val +
+ (BITS(last.bits + last.op) >> last.bits)];
+ if ((unsigned)(last.bits + this.bits) <= bits) break;
+ PULLBYTE();
+ }
+ DROPBITS(last.bits);
+ }
+ DROPBITS(this.bits);
+ state->length = (unsigned)this.val;
+ if ((int)(this.op) == 0) {
+ state->mode = LIT;
+ break;
+ }
+ if (this.op & 32) {
+ state->mode = TYPE;
+ break;
+ }
+ if (this.op & 64) {
+ strm->msg = (char *)"invalid literal/length code";
+ state->mode = BAD;
+ break;
+ }
+ state->extra = (unsigned)(this.op) & 15;
+ state->mode = LENEXT;
+ case LENEXT:
+ if (state->extra) {
+ NEEDBITS(state->extra);
+ state->length += BITS(state->extra);
+ DROPBITS(state->extra);
+ }
+ state->mode = DIST;
+ case DIST:
+ for (;;) {
+ this = state->distcode[BITS(state->distbits)];
+ if ((unsigned)(this.bits) <= bits) break;
+ PULLBYTE();
+ }
+ if ((this.op & 0xf0) == 0) {
+ last = this;
+ for (;;) {
+ this = state->distcode[last.val +
+ (BITS(last.bits + last.op) >> last.bits)];
+ if ((unsigned)(last.bits + this.bits) <= bits) break;
+ PULLBYTE();
+ }
+ DROPBITS(last.bits);
+ }
+ DROPBITS(this.bits);
+ if (this.op & 64) {
+ strm->msg = (char *)"invalid distance code";
+ state->mode = BAD;
+ break;
+ }
+ state->offset = (unsigned)this.val;
+ state->extra = (unsigned)(this.op) & 15;
+ state->mode = DISTEXT;
+ case DISTEXT:
+ if (state->extra) {
+ NEEDBITS(state->extra);
+ state->offset += BITS(state->extra);
+ DROPBITS(state->extra);
+ }
+#ifdef INFLATE_STRICT
+ if (state->offset > state->dmax) {
+ strm->msg = (char *)"invalid distance too far back";
+ state->mode = BAD;
+ break;
+ }
+#endif
+ if (state->offset > state->whave + out - left) {
+ strm->msg = (char *)"invalid distance too far back";
+ state->mode = BAD;
+ break;
+ }
+ state->mode = MATCH;
+ case MATCH:
+ if (left == 0) goto inf_leave;
+ copy = out - left;
+ if (state->offset > copy) { /* copy from window */
+ copy = state->offset - copy;
+ if (copy > state->write) {
+ copy -= state->write;
+ from = state->window + (state->wsize - copy);
+ }
+ else
+ from = state->window + (state->write - copy);
+ if (copy > state->length) copy = state->length;
+ }
+ else { /* copy from output */
+ from = put - state->offset;
+ copy = state->length;
+ }
+ if (copy > left) copy = left;
+ left -= copy;
+ state->length -= copy;
+ do {
+ *put++ = *from++;
+ } while (--copy);
+ if (state->length == 0) state->mode = LEN;
+ break;
+ case LIT:
+ if (left == 0) goto inf_leave;
+ *put++ = (unsigned char)(state->length);
+ left--;
+ state->mode = LEN;
+ break;
+ case CHECK:
+ if (state->wrap) {
+ NEEDBITS(32);
+ out -= left;
+ strm->total_out += out;
+ state->total += out;
+ if (out)
+ strm->adler = state->check =
+ UPDATE(state->check, put - out, out);
+ out = left;
+ if ((
+ REVERSE(hold)) != state->check) {
+ strm->msg = (char *)"incorrect data check";
+ state->mode = BAD;
+ break;
+ }
+ INITBITS();
+ }
+ state->mode = DONE;
+ case DONE:
+ ret = Z_STREAM_END;
+ goto inf_leave;
+ case BAD:
+ ret = Z_DATA_ERROR;
+ goto inf_leave;
+ case MEM:
+ return Z_MEM_ERROR;
+ case SYNC:
+ default:
+ return Z_STREAM_ERROR;
+ }
+
+ /*
+ Return from inflate(), updating the total counts and the check value.
+ If there was no progress during the inflate() call, return a buffer
+ error. Call zlib_updatewindow() to create and/or update the window state.
+ */
+ inf_leave:
+ RESTORE();
+ if (state->wsize || (state->mode < CHECK && out != strm->avail_out))
+ zlib_updatewindow(strm, out);
+
+ in -= strm->avail_in;
+ out -= strm->avail_out;
+ strm->total_in += in;
+ strm->total_out += out;
+ state->total += out;
+ if (state->wrap && out)
+ strm->adler = state->check =
+ UPDATE(state->check, strm->next_out - out, out);
+
+ strm->data_type = state->bits + (state->last ? 64 : 0) +
+ (state->mode == TYPE ? 128 : 0);
+ if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
+ ret = Z_BUF_ERROR;
+
+ if (flush == Z_PACKET_FLUSH && ret == Z_OK &&
+ (strm->avail_out != 0 || strm->avail_in == 0))
+ return zlib_inflateSyncPacket(strm);
+ return ret;
+}
+
+int zlib_inflateEnd(z_streamp strm)
+{
+ if (strm == NULL || strm->state == NULL)
+ return Z_STREAM_ERROR;
return Z_OK;
}
+#if 0
+int zlib_inflateSetDictionary(z_streamp strm, const Byte *dictionary,
+ uInt dictLength)
+{
+ struct inflate_state *state;
+ unsigned long id;
+
+ /* check state */
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ state = (struct inflate_state *)strm->state;
+ if (state->wrap != 0 && state->mode != DICT)
+ return Z_STREAM_ERROR;
+
+ /* check for correct dictionary id */
+ if (state->mode == DICT) {
+ id = zlib_adler32(0L, NULL, 0);
+ id = zlib_adler32(id, dictionary, dictLength);
+ if (id != state->check)
+ return Z_DATA_ERROR;
+ }
+
+ /* copy dictionary to window */
+ zlib_updatewindow(strm, strm->avail_out);
-int zlib_inflateInit_(
- z_streamp z,
- const char *version,
- int stream_size
-)
+ if (dictLength > state->wsize) {
+ memcpy(state->window, dictionary + dictLength - state->wsize,
+ state->wsize);
+ state->whave = state->wsize;
+ }
+ else {
+ memcpy(state->window + state->wsize - dictLength, dictionary,
+ dictLength);
+ state->whave = dictLength;
+ }
+ state->havedict = 1;
+ return Z_OK;
+}
+#endif
+
+#if 0
+/*
+ Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found
+ or when out of input. When called, *have is the number of pattern bytes
+ found in order so far, in 0..3. On return *have is updated to the new
+ state. If on return *have equals four, then the pattern was found and the
+ return value is how many bytes were read including the last byte of the
+ pattern. If *have is less than four, then the pattern has not been found
+ yet and the return value is len. In the latter case, zlib_syncsearch() can be
+ called again with more data and the *have state. *have is initialized to
+ zero for the first call.
+ */
+static unsigned zlib_syncsearch(unsigned *have, unsigned char *buf,
+ unsigned len)
{
- return zlib_inflateInit2_(z, DEF_WBITS, version, stream_size);
+ unsigned got;
+ unsigned next;
+
+ got = *have;
+ next = 0;
+ while (next < len && got < 4) {
+ if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
+ got++;
+ else if (buf[next])
+ got = 0;
+ else
+ got = 4 - got;
+ next++;
+ }
+ *have = got;
+ return next;
}
+#endif
-#undef NEEDBYTE
-#undef NEXTBYTE
-#define NEEDBYTE {if(z->avail_in==0)goto empty;r=trv;}
-#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
+#if 0
+int zlib_inflateSync(z_streamp strm)
+{
+ unsigned len; /* number of bytes to look at or looked at */
+ unsigned long in, out; /* temporary to save total_in and total_out */
+ unsigned char buf[4]; /* to restore bit buffer to byte string */
+ struct inflate_state *state;
+
+ /* check parameters */
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ state = (struct inflate_state *)strm->state;
+ if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
+
+ /* if first time, start search in bit buffer */
+ if (state->mode != SYNC) {
+ state->mode = SYNC;
+ state->hold <<= state->bits & 7;
+ state->bits -= state->bits & 7;
+ len = 0;
+ while (state->bits >= 8) {
+ buf[len++] = (unsigned char)(state->hold);
+ state->hold >>= 8;
+ state->bits -= 8;
+ }
+ state->have = 0;
+ zlib_syncsearch(&(state->have), buf, len);
+ }
+
+ /* search available input */
+ len = zlib_syncsearch(&(state->have), strm->next_in, strm->avail_in);
+ strm->avail_in -= len;
+ strm->next_in += len;
+ strm->total_in += len;
+
+ /* return no joy or set up to restart inflate() on a new block */
+ if (state->have != 4) return Z_DATA_ERROR;
+ in = strm->total_in; out = strm->total_out;
+ zlib_inflateReset(strm);
+ strm->total_in = in; strm->total_out = out;
+ state->mode = TYPE;
+ return Z_OK;
+}
+#endif
-int zlib_inflate(
- z_streamp z,
- int f
-)
+/*
+ * This subroutine adds the data at next_in/avail_in to the output history
+ * without performing any output. The output buffer must be "caught up";
+ * i.e. no pending output but this should always be the case. The state must
+ * be waiting on the start of a block (i.e. mode == TYPE or HEAD). On exit,
+ * the output will also be caught up, and the checksum will have been updated
+ * if need be.
+ */
+int zlib_inflateIncomp(z_stream *z)
{
- int r, trv;
- uInt b;
-
- if (z == NULL || z->state == NULL || z->next_in == NULL)
- return Z_STREAM_ERROR;
- trv = 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 = I_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 = I_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 = I_BAD;
- z->msg = (char*)"incorrect header check";
- z->state->sub.marker = 5; /* can't try inflateSync */
- break;
- }
- 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 = I_BAD;
- z->msg = (char*)"need dictionary";
- z->state->sub.marker = 0; /* can try inflateSync */
- return Z_STREAM_ERROR;
- case BLOCKS:
- r = zlib_inflate_blocks(z->state->blocks, z, r);
- if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
- r = zlib_inflate_packet_flush(z->state->blocks);
- if (r == Z_DATA_ERROR)
- {
- z->state->mode = I_BAD;
- z->state->sub.marker = 0; /* can try inflateSync */
- break;
- }
- if (r == Z_OK)
- r = trv;
- if (r != Z_STREAM_END)
- return r;
- r = trv;
- zlib_inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
- if (z->state->nowrap)
- {
- z->state->mode = I_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 = I_BAD;
- z->msg = (char*)"incorrect data check";
- z->state->sub.marker = 5; /* can't try inflateSync */
- break;
- }
- z->state->mode = I_DONE;
- case I_DONE:
- return Z_STREAM_END;
- case I_BAD:
- return Z_DATA_ERROR;
- default:
- return Z_STREAM_ERROR;
- }
- empty:
- if (f != Z_PACKET_FLUSH)
- return r;
- z->state->mode = I_BAD;
- z->msg = (char *)"need more for packet flush";
- z->state->sub.marker = 0; /* can try inflateSync */
- return Z_DATA_ERROR;
+ struct inflate_state *state = (struct inflate_state *)z->state;
+ Byte *saved_no = z->next_out;
+ uInt saved_ao = z->avail_out;
+
+ if (state->mode != TYPE && state->mode != HEAD)
+ return Z_DATA_ERROR;
+
+ /* Setup some variables to allow misuse of updateWindow */
+ z->avail_out = 0;
+ z->next_out = z->next_in + z->avail_in;
+
+ zlib_updatewindow(z, z->avail_in);
+
+ /* Restore saved variables */
+ z->avail_out = saved_ao;
+ z->next_out = saved_no;
+
+ z->adler = state->check =
+ UPDATE(state->check, z->next_in, z->avail_in);
+
+ z->total_out += z->avail_in;
+ z->total_in += z->avail_in;
+ z->next_in += z->avail_in;
+ state->total += z->avail_in;
+ z->avail_in = 0;
+
+ return Z_OK;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 08:16:16 +0100