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-rw-r--r--libavcodec/Makefile1
-rw-r--r--libavcodec/cscd.c14
-rw-r--r--libavcodec/lzo.c167
-rw-r--r--libavcodec/lzo.h11
4 files changed, 182 insertions, 11 deletions
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 6063dc1a92..db27a14d8e 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -169,6 +169,7 @@ ifeq ($(CONFIG_TSCC_DECODER),yes)
endif
ifeq ($(CONFIG_CSCD_DECODER),yes)
OBJS+= cscd.o
+ OBJS+= lzo.o
endif
ifeq ($(CONFIG_ULTI_DECODER),yes)
OBJS+= ulti.o
diff --git a/libavcodec/cscd.c b/libavcodec/cscd.c
index fdc336d4dc..3e64123515 100644
--- a/libavcodec/cscd.c
+++ b/libavcodec/cscd.c
@@ -25,9 +25,7 @@
#ifdef CONFIG_ZLIB
#include <zlib.h>
#endif
-#ifdef CONFIG_LZO
-#include <lzo1x.h>
-#endif
+#include "lzo.h"
typedef struct {
AVFrame pic;
@@ -158,16 +156,10 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
// decompress data
switch ((buf[0] >> 1) & 7) {
case 0: { // lzo compression
-#ifdef CONFIG_LZO
- unsigned int dlen = c->decomp_size;
- if (lzo1x_decompress_safe(&buf[2], buf_size - 2,
- c->decomp_buf, &dlen, NULL) != LZO_E_OK)
+ int outlen = c->decomp_size, inlen = buf_size - 2;
+ if (lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen))
av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
break;
-#else
- av_log(avctx, AV_LOG_ERROR, "compiled without lzo (GPL) support\n");
- return -1;
-#endif
}
case 1: { // zlib compression
#ifdef CONFIG_ZLIB
diff --git a/libavcodec/lzo.c b/libavcodec/lzo.c
new file mode 100644
index 0000000000..a123abb497
--- /dev/null
+++ b/libavcodec/lzo.c
@@ -0,0 +1,167 @@
+/*
+ * LZO 1x decompression
+ * Copyright (c) 2006 Reimar Doeffinger
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "common.h"
+#include "lzo.h"
+
+typedef struct LZOContext {
+ uint8_t *in, *in_end;
+ uint8_t *out, *out_end;
+ int out_size;
+ 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;
+}
+
+/**
+ * \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;
+}
+
+/**
+ * \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) {
+ if (c->in + cnt > c->in_end) {
+ cnt = c->in_end - c->in;
+ c->error |= LZO_INPUT_DEPLETED;
+ }
+ if (c->out + cnt > c->out_end) {
+ cnt = c->out_end - c->out;
+ c->error |= LZO_OUTPUT_FULL;
+ }
+ do {
+ *c->out++ = *c->in++;
+ } while (--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.
+ */
+static inline void copy_backptr(LZOContext *c, int back, int cnt) {
+ if (c->out - back < c->out_end - c->out_size) {
+ c->error |= LZO_INVALID_BACKPTR;
+ return;
+ }
+ if (c->out + cnt > c->out_end) {
+ cnt = c->out_end - c->out;
+ c->error |= LZO_OUTPUT_FULL;
+ }
+ do {
+ *c->out++ = c->out[-back];
+ } while (--cnt);
+}
+
+/**
+ * \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
+ */
+int lzo1x_decode(void *out, int *outlen, void *in, int *inlen) {
+ enum {COPY, BACKPTR} state = COPY;
+ int x;
+ LZOContext c;
+ c.in = in;
+ c.in_end = in + *inlen;
+ c.out = out;
+ c.out_end = out + * outlen;
+ c.out_size = *outlen;
+ c.error = 0;
+ x = get_byte(&c);
+ if (x > 17) {
+ copy(&c, x - 17);
+ x = get_byte(&c);
+ if (x < 16) c.error |= LZO_ERROR;
+ }
+ while (!c.error) {
+ int cnt, back;
+ if (x >> 4) {
+ state = BACKPTR;
+ if (x >> 6) {
+ cnt = (x >> 5) - 1;
+ back = (get_byte(&c) << 3) + ((x >> 2) & 7) + 1;
+ } else if (x >> 5) {
+ cnt = get_len(&c, x, 31);
+ x = get_byte(&c);
+ back = (get_byte(&c) << 6) + (x >> 2) + 1;
+ } else {
+ cnt = get_len(&c, x, 7);
+ back = (1 << 14) + ((x & 8) << 11);
+ x = get_byte(&c);
+ back += (get_byte(&c) << 6) + (x >> 2);
+ if (back == (1 << 14)) {
+ if (cnt != 1)
+ c.error |= LZO_ERROR;
+ break;
+ }
+ }
+ } else
+ switch (state) {
+ case COPY:
+ cnt = get_len(&c, x, 15);
+ copy(&c, cnt + 3);
+ x = get_byte(&c);
+ if (x >> 4)
+ continue;
+ cnt = 1;
+ back = (1 << 11) + (get_byte(&c) << 2) + (x >> 2) + 1;
+ break;
+ case BACKPTR:
+ cnt = 0;
+ back = (get_byte(&c) << 2) + (x >> 2) + 1;
+ break;
+ }
+ copy_backptr(&c, back, cnt + 2);
+ cnt = x & 3;
+ if (cnt)
+ copy(&c, cnt);
+ else
+ state = (state == COPY) ? BACKPTR : COPY;
+ x = get_byte(&c);
+ }
+ *inlen = c.in_end - c.in;
+ *outlen = c.out_end - c.out;
+ return c.error;
+}
diff --git a/libavcodec/lzo.h b/libavcodec/lzo.h
new file mode 100644
index 0000000000..3c1388e191
--- /dev/null
+++ b/libavcodec/lzo.h
@@ -0,0 +1,11 @@
+#ifndef _LZO_H
+#define LZO_H
+
+#define LZO_INPUT_DEPLETED 1
+#define LZO_OUTPUT_FULL 2
+#define LZO_INVALID_BACKPTR 4
+#define LZO_ERROR 8
+
+int lzo1x_decode(void *out, int *outlen, void *in, int *inlen);
+
+#endif
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