- Made CRYPTO_MDEBUG even less used in crypto.h, giving
MemCheck_start() and MemCheck_stop() only one possible definition.
- Made the values of the debug function pointers in mem.c dependent
on the existence of the CRYPTO_MDEBUG macro, and made the rest of
the code understand the NULL case.
That's it. With this code, the old behvior of the debug functionality
is restored, but you can still opt to have it on, even when the
library wasn't compiled with a defined CRYPTO_MDEBUG.
With this change, the following is provided and present at all times
(meaning CRYPTO_MDEBUG is no longer required to get this functionality):
- hooks to provide your own allocation and deallocation routines.
They have to have the same interface as malloc(), realloc() and
free(). They are registered by calling CRYPTO_set_mem_functions()
with the function pointers.
- hooks to provide your own memory debugging routines. The have to
have the same interface as as the CRYPTO_dbg_*() routines. They
are registered by calling CRYPTO_set_mem_debug_functions() with
the function pointers.
I moved everything that was already built into OpenSSL and did memory
debugging to a separate file (mem_dbg.c), to make it clear what is
what.
With this, the relevance of the CRYPTO_MDEBUG has changed. The only
thing in crypto/crypto.h that it affects is the definition of the
MemCheck_start and MemCheck_stop macros.
1. Added code to the memory leak detecting code to give the user the
possibility to add information, thereby forming a traceback.
2. Make the memory leak detecting code multithread-safe.
The idea is that we're actually dealing with two separate critical
sections, one containing the hash tables with the information, the
other containing the current memory checking mode. Those should not
be handled with the same lock, especially since their handling overlap.
Hence, the added second lock.