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authorMike Gabriel <mike.gabriel@das-netzwerkteam.de>2011-11-19 15:59:26 +0100
committerMike Gabriel <mike.gabriel@das-netzwerkteam.de>2011-11-19 15:59:26 +0100
commit5e502cbb195be17d5d742295f4a2e6f0c603a8d7 (patch)
treef9e188b59c7e608bc862dd740ecd459c5a83dfc9 /nxcompext/Z.c
parenta48361b11a5abb5a345dac5ec83a8f56c4d50b74 (diff)
parent88dace9a99687840f3fb341f0316cd94399cae9e (diff)
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Merge branch 'nxcompext'
Diffstat (limited to 'nxcompext/Z.c')
-rw-r--r--nxcompext/Z.c301
1 files changed, 301 insertions, 0 deletions
diff --git a/nxcompext/Z.c b/nxcompext/Z.c
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+/**************************************************************************/
+/* */
+/* Copyright (c) 2001, 2007 NoMachine, http://www.nomachine.com/. */
+/* */
+/* NXCOMPEXT, NX protocol compression and NX extensions to this software */
+/* are copyright of NoMachine. Redistribution and use of the present */
+/* software is allowed according to terms specified in the file LICENSE */
+/* which comes in the source distribution. */
+/* */
+/* Check http://www.nomachine.com/licensing.html for applicability. */
+/* */
+/* NX and NoMachine are trademarks of NoMachine S.r.l. */
+/* */
+/* All rigths reserved. */
+/* */
+/**************************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <zlib.h>
+
+#include "NXlib.h"
+
+#include "Z.h"
+
+#define PANIC
+#define WARNING
+#undef TEST
+#undef DEBUG
+
+#define Z_COMPRESSION_LEVEL 4
+#define Z_COMPRESSION_THRESHOLD 32
+#define Z_COMPRESSION_STRATEGY Z_DEFAULT_STRATEGY
+
+static int zCompressionLevel = Z_COMPRESSION_LEVEL;
+static int zCompressionStrategy = Z_COMPRESSION_STRATEGY;
+
+static z_stream *zStream;
+
+static int zInitialized;
+
+static int ZConfigure(int level, int strategy);
+
+static int ZDeflate(char *dest, unsigned int *destLen,
+ const char *source, unsigned int sourceLen);
+
+char *ZCompressData(const char *plainData, unsigned int plainSize, int threshold,
+ int level, int strategy, unsigned int *compressedSize)
+{
+ char *compressedData;
+
+ /*
+ * Determine the size of the source image
+ * data and make sure there is enough
+ * space in the destination buffer.
+ */
+
+ *compressedSize = plainSize + (plainSize / 1000) + 12 + 1;
+
+ compressedData = Xmalloc(*compressedSize);
+
+ if (compressedData == NULL)
+ {
+ #ifdef PANIC
+ fprintf(stderr, "******ZCompressData: PANIC! Failed to allocate [%d] bytes for the destination.\n",
+ *compressedSize);
+ #endif
+
+ *compressedSize = 0;
+
+ return NULL;
+ }
+
+ if (level == Z_NO_COMPRESSION || plainSize < threshold)
+ {
+ #ifdef TEST
+ fprintf(stderr, "******ZCompressData: Not compressing [%d] bytes with level [%d] and "
+ "threshold [%d].\n", plainSize, level, threshold);
+ #endif
+
+ /*
+ * Tell in the first byte of the buffer
+ * if the remaining data is compressed
+ * or not. This same byte can be used
+ * in future to store some other flag.
+ */
+
+ *compressedData = 0;
+
+ memcpy(compressedData + 1, plainData, plainSize);
+
+ *compressedSize = plainSize + 1;
+
+ return compressedData;
+ }
+ else
+ {
+ int result;
+
+ /*
+ * Reconfigure the stream if needed.
+ */
+
+ if (zCompressionLevel != level ||
+ zCompressionStrategy != strategy)
+ {
+ ZConfigure(level, strategy);
+
+ zCompressionLevel = level;
+ zCompressionStrategy = strategy;
+ }
+
+ result = ZDeflate(compressedData + 1, compressedSize, plainData, plainSize);
+
+ if (result != Z_OK)
+ {
+ #ifdef PANIC
+ fprintf(stderr, "******ZCompressData: PANIC! Failed to compress [%d] bytes with error [%s].\n",
+ plainSize, zError(result));
+ #endif
+
+ Xfree(compressedData);
+
+ *compressedSize = 0;
+
+ return NULL;
+ }
+
+ #ifdef TEST
+ fprintf(stderr, "******ZCompressData: Source data of [%d] bytes compressed to [%d].\n",
+ plainSize, *compressedSize);
+ #endif
+
+ *compressedData = 1;
+
+ *compressedSize = *compressedSize + 1;
+
+ return compressedData;
+ }
+}
+
+int ZConfigure(int level, int strategy)
+{
+ /*
+ * ZLIB wants the avail_out to be
+ * non zero, even if the stream was
+ * already flushed.
+ */
+
+ unsigned char dest[1];
+
+ zStream -> next_out = dest;
+ zStream -> avail_out = 1;
+
+ if (deflateParams(zStream, level, strategy) != Z_OK)
+ {
+ #ifdef PANIC
+ fprintf(stderr, "******ZConfigure: PANIC! Failed to set level to [%d] and strategy to [%d].\n",
+ level, strategy);
+ #endif
+
+ return -1;
+ }
+ #ifdef TEST
+ else
+ {
+ fprintf(stderr, "******ZConfigure: Reconfigured the stream with level [%d] and strategy [%d].\n",
+ level, strategy);
+ }
+ #endif
+
+ return 1;
+}
+
+int ZDeflate(char *dest, unsigned int *destLen, const char *source, unsigned int sourceLen)
+{
+ int saveOut;
+ int result;
+
+ /*
+ * Deal with the possible overflow.
+ */
+
+ if (zStream -> total_out & 0x80000000)
+ {
+ #ifdef TEST
+ fprintf(stderr, "******ZDeflate: Reset Z stream counters with total in [%ld] total out [%ld].\n",
+ zStream -> total_in, zStream -> total_out);
+ #endif
+
+ zStream -> total_in = 0;
+ zStream -> total_out = 0;
+ }
+
+ saveOut = zStream -> total_out;
+
+ zStream -> next_in = (Bytef *) source;
+ zStream -> avail_in = (uInt) sourceLen;
+
+ #ifdef MAXSEG_64K
+
+ /*
+ * Check if the source is greater
+ * than 64K on a 16-bit machine.
+ */
+
+ if ((uLong) zStream -> avail_in != sourceLen) return Z_BUF_ERROR;
+
+ #endif
+
+ zStream -> next_out = (unsigned char *) dest;
+ zStream -> avail_out = (uInt) *destLen;
+
+ if ((uLong) zStream -> avail_out != *destLen) return Z_BUF_ERROR;
+
+ result = deflate(zStream, Z_FINISH);
+
+ if (result != Z_STREAM_END)
+ {
+ deflateReset(zStream);
+
+ return (result == Z_OK ? Z_BUF_ERROR : result);
+ }
+
+ *destLen = zStream -> total_out - saveOut;
+
+ result = deflateReset(zStream);
+
+ return result;
+}
+
+int ZInitEncoder()
+{
+ if (zInitialized == 0)
+ {
+ int result;
+
+ zStream = Xmalloc(sizeof(z_stream));
+
+ if (zStream == NULL)
+ {
+ #ifdef PANIC
+ fprintf(stderr, "******ZInitEncoder: PANIC! Failed to allocate memory for the stream.\n");
+ #endif
+
+ return -1;
+ }
+
+ zStream -> zalloc = (alloc_func) 0;
+ zStream -> zfree = (free_func) 0;
+ zStream -> opaque = (voidpf) 0;
+
+ #ifdef TEST
+ fprintf(stderr, "******ZInitEncoder: Initializing compressor with level [%d] and startegy [%d].\n",
+ zCompressionLevel, zCompressionStrategy);
+ #endif
+
+ result = deflateInit2(zStream, zCompressionLevel, Z_DEFLATED,
+ 15, 9, zCompressionStrategy);
+
+ if (result != Z_OK)
+ {
+ #ifdef PANIC
+ fprintf(stderr, "******ZInitEncoder: Failed to initialize the compressor with error [%s].\n",
+ zError(result));
+ #endif
+
+ return -1;
+ }
+
+ zInitialized = 1;
+ }
+
+ return zInitialized;
+}
+
+int ZResetEncoder()
+{
+ int result;
+
+ if (zInitialized == 1)
+ {
+ result = deflateEnd(zStream);
+
+ if (result != Z_OK)
+ {
+ #ifdef WARNING
+ fprintf(stderr, "******ZResetEncoder: WARNING! Failed to deinitialize the compressor with error [%s].\n",
+ zError(result));
+ #endif
+ }
+
+ Xfree(zStream);
+ }
+
+ zInitialized = 0;
+
+ return 1;
+}