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

Age	Commit message (Collapse)	Author	Lines
2020-04-30	fix undefined behavior from signed overflow in strstr and memmem	Rich Felker	-4/+4
	unsigned char promotes to int, which can overflow when shifted left by 24 bits or more. this has been reported multiple times but then forgotten. it's expected to be benign UB, but can trap when built with explicit overflow catching (ubsan or similar). fix it now. note that promotion to uint32_t is safe and portable even outside of the assumptions usually made in musl, since either uint32_t has rank at least unsigned int, so that no further default promotions happen, or int is wide enough that the shift can't overflow. this is a desirable property to have in case someone wants to reuse the code elsewhere.
2018-11-08	optimize two-way strstr and memmem bad character shift	Rich Felker	-1/+1
	first, the condition (mem && k < p) is redundant, because mem being nonzero implies the needle is periodic with period exactly p, in which case any byte that appears in the needle must appear in the last p bytes of the needle, bounding the shift (k) by p. second, the whole point of replacing the shift k by mem (=l-p) is to prevent shifting by less than mem when discarding the memory on shift, in which case linear time could not be guaranteed. but as written, the check also replaced shifts greater than mem by mem, reducing the benefit of the shift. there is no possible benefit to this reduction of the shift; since mem is being cleared, the full shift is valid and more optimal. so only replace the shift by mem when it would be less than mem.
2018-11-02	remove commented-out debug printf from strstr	Rich Felker	-1/+0
	this was leftover from before the initial commit.
2018-11-02	fix spuriously slow check in twoway strstr/memmem cores	Rich Felker	-1/+1
	mem0 && mem && ... is redundant since mem can only be nonzero when mem0 is nonzero.
2014-04-18	fix false negatives with periodic needles in strstr, wcsstr, and memmem	Rich Felker	-1/+1
	in cases where the memorized match range from the right factor exceeded the length of the left factor, it was wrongly treated as a mismatch rather than a match. issue reported by Yves Bastide.
2013-12-12	include cleanups: remove unused headers and add feature test macros	Szabolcs Nagy	-1/+0

2012-08-11	remove unused but buggy code from strstr.c	Rich Felker	-10/+0

2011-03-25	fix all implicit conversion between signed/unsigned pointers	Rich Felker	-5/+5
	sadly the C language does not specify any such implicit conversion, so this is not a matter of just fixing warnings (as gcc treats it) but actual errors. i would like to revisit a number of these changes and possibly revise the types used to reduce the number of casts required.
2011-02-12	initial check-in, version 0.5.0v0.5.0	Rich Felker	-0/+166