2002-10-13 18:34:33 +08:00
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$Id$
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\___|\___/|_| \_\_____|
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How To Track Down Suspected Memory Leaks in libcurl
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===================================================
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2002-10-29 05:05:14 +08:00
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Single-threaded
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Please note that this memory leak system is not adjusted to work in more
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than one thread. If you want/need to use it in a multi-threaded app. Please
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adjust accordingly.
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2002-10-13 18:34:33 +08:00
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Build
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2003-07-22 18:00:37 +08:00
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Rebuild libcurl with -DCURLDEBUG (usually, rerunning configure with
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2002-10-13 18:34:33 +08:00
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--enable-debug fixes this). 'make clean' first, then 'make' so that all
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files actually are rebuilt properly. It will also make sense to build
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libcurl with the debug option (usually -g to the compiler) so that debugging
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it will be easier if you actually do find a leak in the library.
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This will create a library that has memory debugging enabled.
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Modify Your Application
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Add a line in your application code:
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2006-10-30 07:00:52 +08:00
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curl_memdebug("dump");
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2002-10-13 18:34:33 +08:00
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This will make the malloc debug system output a full trace of all resource
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using functions to the given file name. Make sure you rebuild your program
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and that you link with the same libcurl you built for this purpose as
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described above.
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Run Your Application
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Run your program as usual. Watch the specified memory trace file grow.
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Make your program exit and use the proper libcurl cleanup functions etc. So
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that all non-leaks are returned/freed properly.
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Analyze the Flow
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2006-10-30 07:00:52 +08:00
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Use the tests/memanalyze.pl perl script to analyze the dump file:
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2002-10-13 18:34:33 +08:00
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2006-10-30 07:00:52 +08:00
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tests/memanalyze.pl dump
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2002-10-13 18:34:33 +08:00
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This now outputs a report on what resources that were allocated but never
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freed etc. This report is very fine for posting to the list!
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If this doesn't produce any output, no leak was detected in libcurl. Then
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the leak is mostly likely to be in your code.
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