fixed bug in gunzip

Author: arvidn

ChangeLog

@@ -46,6 +46,7 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* fixed bug in gunzip
 	* fix to use proxy settings when adding .torrent file from URL
 	* fix resume file issue related to daylight savings time on windows
 	* improve error checking in lazy_bdecode

src/gzip.cpp

@@ -150,6 +150,9 @@ namespace libtorrent
 		// if needed
 		boost::uint32_t destlen = 4096;
 		int ret = 0;
+		boost::uint32_t srclen = size - header_len;
+		in += header_len;
+
 		do
 		{
 			TORRENT_TRY {
@@ -158,15 +161,13 @@ namespace libtorrent
 				error = "out of memory";
 				return true;
 			}
-   
-			boost::uint32_t srclen = size - header_len;
-			in += header_len;
+
 			ret = puff((unsigned char*)&buffer[0], &destlen, (unsigned char*)in, &srclen);
-   
+
 			// if the destination buffer wasn't large enough, double its
 			// size and try again. Unless it's already at its max, in which
 			// case we fail
-			if (ret == -1)
+			if (ret == 1) // 1:  output space exhausted before completing inflate
 			{
 				if (destlen == maximum_size)
 				{
@@ -177,9 +178,14 @@ namespace libtorrent
 				destlen *= 2;
 				if (destlen > maximum_size)
 					destlen = maximum_size;
-				continue;
 			}
-		} while (false);
+		} while (ret == 1);
+
+		if (ret != 0)
+		{
+			error = "error while inflating data";
+			return true;
+		}
 
 		if (destlen > buffer.size())
 		{
@@ -189,11 +195,6 @@ namespace libtorrent
 
 		buffer.resize(destlen);
 
-		if (ret != 0)
-		{
-			error = "error while inflating data";
-			return true;
-		}
 		return false;
 	}
 

test/Jamfile

@@ -88,6 +88,7 @@ feature launcher : none valgrind : composite ;
 feature.compose <launcher>valgrind : <testing.launcher>"valgrind --tool=memcheck -v --num-callers=20 --read-var-info=yes --track-origins=yes --error-exitcode=222 --suppressions=valgrind_suppressions.txt" <valgrind>on ;
 
 test-suite libtorrent : 	
+	[ run test_gzip.cpp ]
 	[ run test_bitfield.cpp ]
 	[ run test_torrent_info.cpp ]
 	[ run test_time.cpp ]

test/Makefile.am

@@ -99,7 +99,8 @@ EXTRA_DIST = Jamfile \
   cb.xml \
   mn.xml \
   pb.xml \
-  upnp.xml
+  upnp.xml \
+  zeroes.gz
 
 EXTRA_PROGRAMS = $(test_programs)
 

test/test_gzip.cpp

@@ -0,0 +1,64 @@
+/*
+
+Copyright (c) 2014, Arvid Norberg
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in
+      the documentation and/or other materials provided with the distribution.
+    * Neither the name of the author nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#include "libtorrent/file.hpp"
+#include "test.hpp"
+#include "libtorrent/gzip.hpp"
+#include "setup_transfer.hpp" // for load_file
+#include "file.hpp" // for combine_path
+
+using namespace libtorrent;
+
+int test_main()
+{
+	std::vector<char> zipped;
+	error_code ec;
+	int r = load_file(combine_path("..", "zeroes.gz"), zipped, ec, 1000000);
+	if (ec) fprintf(stderr, "failed to open file: (%d) %s\n", ec.value()
+		, ec.message().c_str());
+	TEST_CHECK(!ec);
+
+	std::vector<char> inflated;
+	std::string error;
+	bool ret = inflate_gzip(&zipped[0], zipped.size(), inflated, 1000000, error);
+
+	if (ret != 0) {
+		fprintf(stderr, "failed to unzip\n");
+	}
+	TEST_CHECK(ret == 0);
+	TEST_CHECK(inflated.size() > 0);
+	for (int i = 0; i < inflated.size(); ++i)
+		TEST_EQUAL(inflated[i], 0);
+
+	return 0;
+}
+