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-rw-r--r--gst/matroska/lzo.c288
1 files changed, 288 insertions, 0 deletions
diff --git a/gst/matroska/lzo.c b/gst/matroska/lzo.c
new file mode 100644
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--- /dev/null
+++ b/gst/matroska/lzo.c
@@ -0,0 +1,288 @@
+/*
+ * LZO 1x decompression
+ * Copyright (c) 2006 Reimar Doeffinger
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <gst/gst.h>
+#include <stdlib.h>
+#include <string.h>
+#include "_stdint.h"
+#include "lzo.h"
+
+/*! define if we may write up to 12 bytes beyond the output buffer */
+/* #define OUTBUF_PADDED 1 */
+/*! define if we may read up to 8 bytes beyond the input buffer */
+/* #define INBUF_PADDED 1 */
+typedef struct LZOContext
+{
+ const uint8_t *in, *in_end;
+ uint8_t *out_start, *out, *out_end;
+ int error;
+} LZOContext;
+
+/**
+ * \brief read one byte from input buffer, avoiding overrun
+ * \return byte read
+ */
+static inline int
+get_byte (LZOContext * c)
+{
+ if (c->in < c->in_end)
+ return *c->in++;
+ c->error |= LZO_INPUT_DEPLETED;
+ return 1;
+}
+
+#ifdef INBUF_PADDED
+#define GETB(c) (*(c).in++)
+#else
+#define GETB(c) get_byte(&(c))
+#endif
+
+/**
+ * \brief decode a length value in the coding used by lzo
+ * \param x previous byte value
+ * \param mask bits used from x
+ * \return decoded length value
+ */
+static inline int
+get_len (LZOContext * c, int x, int mask)
+{
+ int cnt = x & mask;
+ if (!cnt) {
+ while (!(x = get_byte (c)))
+ cnt += 255;
+ cnt += mask + x;
+ }
+ return cnt;
+}
+
+/*#define UNALIGNED_LOADSTORE */
+#define BUILTIN_MEMCPY
+#ifdef UNALIGNED_LOADSTORE
+#define COPY2(d, s) *(uint16_t *)(d) = *(uint16_t *)(s);
+#define COPY4(d, s) *(uint32_t *)(d) = *(uint32_t *)(s);
+#elif defined(BUILTIN_MEMCPY)
+#define COPY2(d, s) memcpy(d, s, 2);
+#define COPY4(d, s) memcpy(d, s, 4);
+#else
+#define COPY2(d, s) (d)[0] = (s)[0]; (d)[1] = (s)[1];
+#define COPY4(d, s) (d)[0] = (s)[0]; (d)[1] = (s)[1]; (d)[2] = (s)[2]; (d)[3] = (s)[3];
+#endif
+
+/**
+ * \brief copy bytes from input to output buffer with checking
+ * \param cnt number of bytes to copy, must be >= 0
+ */
+static inline void
+copy (LZOContext * c, int cnt)
+{
+ register const uint8_t *src = c->in;
+ register uint8_t *dst = c->out;
+ if (cnt > c->in_end - src) {
+ cnt = MAX (c->in_end - src, 0);
+ c->error |= LZO_INPUT_DEPLETED;
+ }
+ if (cnt > c->out_end - dst) {
+ cnt = MAX (c->out_end - dst, 0);
+ c->error |= LZO_OUTPUT_FULL;
+ }
+#if defined(INBUF_PADDED) && defined(OUTBUF_PADDED)
+ COPY4 (dst, src);
+ src += 4;
+ dst += 4;
+ cnt -= 4;
+ if (cnt > 0)
+#endif
+ memcpy (dst, src, cnt);
+ c->in = src + cnt;
+ c->out = dst + cnt;
+}
+
+/**
+ * \brief copy previously decoded bytes to current position
+ * \param back how many bytes back we start
+ * \param cnt number of bytes to copy, must be >= 0
+ *
+ * cnt > back is valid, this will copy the bytes we just copied,
+ * thus creating a repeating pattern with a period length of back.
+ */
+static inline void
+copy_backptr (LZOContext * c, int back, int cnt)
+{
+ register const uint8_t *src = &c->out[-back];
+ register uint8_t *dst = c->out;
+ if (src < c->out_start || src > dst) {
+ c->error |= LZO_INVALID_BACKPTR;
+ return;
+ }
+ if (cnt > c->out_end - dst) {
+ cnt = MAX (c->out_end - dst, 0);
+ c->error |= LZO_OUTPUT_FULL;
+ }
+ if (back == 1) {
+ memset (dst, *src, cnt);
+ dst += cnt;
+ } else {
+#ifdef OUTBUF_PADDED
+ COPY2 (dst, src);
+ COPY2 (dst + 2, src + 2);
+ src += 4;
+ dst += 4;
+ cnt -= 4;
+ if (cnt > 0) {
+ COPY2 (dst, src);
+ COPY2 (dst + 2, src + 2);
+ COPY2 (dst + 4, src + 4);
+ COPY2 (dst + 6, src + 6);
+ src += 8;
+ dst += 8;
+ cnt -= 8;
+ }
+#endif
+ if (cnt > 0) {
+ int blocklen = back;
+ while (cnt > blocklen) {
+ memcpy (dst, src, blocklen);
+ dst += blocklen;
+ cnt -= blocklen;
+ blocklen <<= 1;
+ }
+ memcpy (dst, src, cnt);
+ }
+ dst += cnt;
+ }
+ c->out = dst;
+}
+
+/**
+ * \brief decode LZO 1x compressed data
+ * \param out output buffer
+ * \param outlen size of output buffer, number of bytes left are returned here
+ * \param in input buffer
+ * \param inlen size of input buffer, number of bytes left are returned here
+ * \return 0 on success, otherwise error flags, see lzo.h
+ *
+ * make sure all buffers are appropriately padded, in must provide
+ * LZO_INPUT_PADDING, out must provide LZO_OUTPUT_PADDING additional bytes
+ */
+int
+lzo1x_decode (void *out, int *outlen, const void *in, int *inlen)
+{
+ int state = 0;
+ int x;
+ LZOContext c;
+ c.in = in;
+ c.in_end = (const uint8_t *) in + *inlen;
+ c.out = c.out_start = out;
+ c.out_end = (uint8_t *) out + *outlen;
+ c.error = 0;
+ x = GETB (c);
+ if (x > 17) {
+ copy (&c, x - 17);
+ x = GETB (c);
+ if (x < 16)
+ c.error |= LZO_ERROR;
+ }
+ if (c.in > c.in_end)
+ c.error |= LZO_INPUT_DEPLETED;
+ while (!c.error) {
+ int cnt, back;
+ if (x > 15) {
+ if (x > 63) {
+ cnt = (x >> 5) - 1;
+ back = (GETB (c) << 3) + ((x >> 2) & 7) + 1;
+ } else if (x > 31) {
+ cnt = get_len (&c, x, 31);
+ x = GETB (c);
+ back = (GETB (c) << 6) + (x >> 2) + 1;
+ } else {
+ cnt = get_len (&c, x, 7);
+ back = (1 << 14) + ((x & 8) << 11);
+ x = GETB (c);
+ back += (GETB (c) << 6) + (x >> 2);
+ if (back == (1 << 14)) {
+ if (cnt != 1)
+ c.error |= LZO_ERROR;
+ break;
+ }
+ }
+ } else if (!state) {
+ cnt = get_len (&c, x, 15);
+ copy (&c, cnt + 3);
+ x = GETB (c);
+ if (x > 15)
+ continue;
+ cnt = 1;
+ back = (1 << 11) + (GETB (c) << 2) + (x >> 2) + 1;
+ } else {
+ cnt = 0;
+ back = (GETB (c) << 2) + (x >> 2) + 1;
+ }
+ copy_backptr (&c, back, cnt + 2);
+ state = cnt = x & 3;
+ copy (&c, cnt);
+ x = GETB (c);
+ }
+ *inlen = c.in_end - c.in;
+ if (c.in > c.in_end)
+ *inlen = 0;
+ *outlen = c.out_end - c.out;
+ return c.error;
+}
+
+#ifdef TEST
+#include <stdio.h>
+#include <lzo/lzo1x.h>
+#include "log.h"
+#define MAXSZ (10*1024*1024)
+int
+main (int argc, char *argv[])
+{
+ FILE *in = fopen (argv[1], "rb");
+ uint8_t *orig = av_malloc (MAXSZ + 16);
+ uint8_t *comp = av_malloc (2 * MAXSZ + 16);
+ uint8_t *decomp = av_malloc (MAXSZ + 16);
+ size_t s = fread (orig, 1, MAXSZ, in);
+ lzo_uint clen = 0;
+ long tmp[LZO1X_MEM_COMPRESS];
+ int inlen, outlen;
+ int i;
+ av_log_level = AV_LOG_DEBUG;
+ lzo1x_999_compress (orig, s, comp, &clen, tmp);
+ for (i = 0; i < 300; i++) {
+ START_TIMER inlen = clen;
+ outlen = MAXSZ;
+#ifdef LIBLZO
+ if (lzo1x_decompress_safe (comp, inlen, decomp, &outlen, NULL))
+#elif defined(LIBLZO_UNSAFE)
+ if (lzo1x_decompress (comp, inlen, decomp, &outlen, NULL))
+#else
+ if (lzo1x_decode (decomp, &outlen, comp, &inlen))
+#endif
+ av_log (NULL, AV_LOG_ERROR, "decompression error\n");
+ STOP_TIMER ("lzod")
+ }
+ if (memcmp (orig, decomp, s))
+ av_log (NULL, AV_LOG_ERROR, "decompression incorrect\n");
+ else
+ av_log (NULL, AV_LOG_ERROR, "decompression ok\n");
+ return 0;
+}
+#endif
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