Merge further fixes to Zlib encoder from 1.1 branch
git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4623 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/rdr/ZlibOutStream.cxx b/common/rdr/ZlibOutStream.cxx
index c86a5a5..f04536f 100644
--- a/common/rdr/ZlibOutStream.cxx
+++ b/common/rdr/ZlibOutStream.cxx
@@ -29,7 +29,8 @@
ZlibOutStream::ZlibOutStream(OutStream* os, int bufSize_, int compressLevel)
: underlying(os), compressionLevel(compressLevel), newLevel(compressLevel),
- bufSize(bufSize_ ? bufSize_ : DEFAULT_BUF_SIZE), offset(0)
+ bufSize(bufSize_ ? bufSize_ : DEFAULT_BUF_SIZE), offset(0),
+ newBehavior(false)
{
zs = new z_stream;
zs->zalloc = Z_NULL;
@@ -41,6 +42,8 @@
}
ptr = start = new U8[bufSize];
end = start + bufSize;
+ const char *version = zlibVersion();
+ if (strcmp(version, "1.2.3") > 0) newBehavior = true;
}
ZlibOutStream::~ZlibOutStream()
@@ -79,6 +82,9 @@
// fprintf(stderr,"zos flush: avail_in %d\n",zs->avail_in);
+ if (!underlying)
+ throw Exception("ZlibOutStream: underlying OutStream has not been set");
+
while (zs->avail_in != 0) {
do {
@@ -112,6 +118,9 @@
if (itemSize > bufSize)
throw Exception("ZlibOutStream overrun: max itemSize exceeded");
+ if (!underlying)
+ throw Exception("ZlibOutStream: underlying OutStream has not been set");
+
while (end - ptr < itemSize) {
zs->next_in = start;
zs->avail_in = ptr - start;
@@ -124,11 +133,11 @@
// fprintf(stderr,"zos overrun: calling deflate, avail_in %d, avail_out %d\n",
// zs->avail_in,zs->avail_out);
- checkCompressionLevel();
- if (zs->avail_in != 0) {
- int rc = deflate(zs, 0);
- if (rc != Z_OK) throw Exception("ZlibOutStream: deflate failed");
- }
+ checkCompressionLevel();
+ if (zs->avail_in != 0) {
+ int rc = deflate(zs, 0);
+ if (rc != Z_OK) throw Exception("ZlibOutStream: deflate failed");
+ }
// fprintf(stderr,"zos overrun: after deflate: %d bytes\n",
// zs->next_out-underlying->getptr());
@@ -160,6 +169,17 @@
void ZlibOutStream::checkCompressionLevel()
{
if (newLevel != compressionLevel) {
+
+ // This is a horrible hack, but after many hours of trying, I couldn't find
+ // a better way to make this class work properly with both Zlib 1.2.3 and
+ // 1.2.5. 1.2.3 does a Z_PARTIAL_FLUSH in the body of deflateParams() if
+ // the compression level has changed, and 1.2.5 does a Z_BLOCK flush.
+
+ if (newBehavior) {
+ int rc = deflate(zs, Z_SYNC_FLUSH);
+ if (rc != Z_OK) throw Exception("ZlibOutStream: deflate failed");
+ }
+
if (deflateParams (zs, newLevel, Z_DEFAULT_STRATEGY) != Z_OK) {
throw Exception("ZlibOutStream: deflateParams failed");
}