musl - musl - an implementation of the standard library for Linux-based systems

Age	Commit message (Collapse)	Author	Lines
2013-07-23	remove redundant check in memalign	Rich Felker	-1/+1
	the case where mem was already aligned is handled earlier in the function now.
2013-07-23	fix heap corruption bug in memalign	Rich Felker	-1/+3
	this bug was caught by the new footer-corruption check in realloc and free. if the block returned by malloc was already aligned to the desired alignment, memalign's logic to split off the misaligned head was incorrect; rather than writing to a point inside the allocated block, it was overwriting the footer of the previous block on the heap with the value 1 (length 0 plus an in-use flag). fortunately, the impact of this bug was fairly low. (this is probably why it was not caught sooner.) due to the way the heap works, malloc will never return a block whose previous block is free. (doing so would be harmful because it would increase fragmentation with no benefit.) the footer is actually not needed for in-use blocks, except that its in-use bit needs to remain set so that it does not get merged with free blocks, so there was no harm in it being set to 1 instead of the correct value. however, there is one case where this bug could have had an impact: in multi-threaded programs, if another thread freed the previous block after memalign's call to malloc returned, but before memalign overwrote the previous block's footer, the resulting block in the free list could be left in a corrupt state. I have not analyzed the impact of this bad state and whether it could lead to more serious malfunction.
2013-07-04	move core memalign code from aligned_alloc to __memalign	Rich Felker	-2/+50
	there are two motivations for this change. one is to avoid gratuitously depending on a C11 symbol for implementing a POSIX function. the other pertains to the documented semantics. C11 does not define any behavior for aligned_alloc when the length argument is not a multiple of the alignment argument. posix_memalign on the other hand places no requirements on the length argument. using __memalign as the implementation of both, rather than trying to implement one in terms of the other when their documented contracts differ, eliminates this confusion.
2012-08-25	implement "low hanging fruit" from C11	Rich Felker	-7/+1
	based on Gregor's patch sent to the list. includes: - stdalign.h - removing gets in C11 mode - adding aligned_alloc and adjusting other functions to use it - adding 'x' flag to fopen for exclusive mode
2011-02-12	initial check-in, version 0.5.0v0.5.0	Rich Felker	-0/+13