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

Age	Commit message (Collapse)	Author	Lines
2011-09-27	fix crash in pthread_testcancel if pthread_self has not been called	Rich Felker	-1/+1

2011-08-07	close should not be cancellable after "failing" with EINTR	Rich Felker	-1/+2
	normally we allow cancellation to be acted upon when a syscall fails with EINTR, since there is no useful status to report to the caller in this case, and the signal that caused the interruption was almost surely the cancellation request, anyway. however, unlike all other syscalls, close has actually performed its resource-deallocation function whenever it returns, even when it returned an error. if we allow cancellation at this point, the caller has no way of informing the program that the file descriptor was closed, and the program may later try to close the file descriptor again, possibly closing a different, newly-opened file. the workaround looks ugly (special-casing one syscall), but it's actually the case that close is the one and only syscall (at least among cancellation points) with this ugly property.
2011-08-06	use weak aliases rather than function pointers to simplify some code	Rich Felker	-2/+1

2011-08-02	fix breakage in cancellation due to signal functions overhaul	Rich Felker	-1/+7
	sigaddset was not accepting SIGCANCEL as a valid signal number.
2011-04-18	recheck cancellation disabled flag after syscall returns EINTR	Rich Felker	-1/+1
	we already checked before making the syscall, but it's possible that a signal handler interrupted the blocking syscall and disabled cancellation, and that this is the cause of EINTR. in this case, the old behavior was testably wrong.
2011-04-17	clean up handling of thread/nothread mode, locking	Rich Felker	-1/+1

2011-04-17	fix bugs in cancellable syscall asm	Rich Felker	-1/+2
	x86_64 was just plain wrong in the cancel-flag-already-set path, and crashing. the more subtle error was not clearing the saved stack pointer before returning to c code. this could result in the signal handler misidentifying c code as the pre-syscall part of the asm, and acting on cancellation at the wrong time, and thus resource leak race conditions. also, now __cancel (in the c code) is responsible for clearing the saved sp in the already-cancelled branch. this means we have to use call rather than jmp to ensure the stack pointer in the c will never match what the asm saved.
2011-04-17	don't use pthread_once when there is no danger in race	Rich Felker	-2/+5

2011-04-17	fix some minor issues in cancellation handling patch	Rich Felker	-9/+17
	signals were wrongly left masked, and cancellability state was not switched to disabled, during the execution of cleanup handlers.
2011-04-17	overhaul pthread cancellation	Rich Felker	-0/+70
	this patch improves the correctness, simplicity, and size of cancellation-related code. modulo any small errors, it should now be completely conformant, safe, and resource-leak free. the notion of entering and exiting cancellation-point context has been completely eliminated and replaced with alternative syscall assembly code for cancellable syscalls. the assembly is responsible for setting up execution context information (stack pointer and address of the syscall instruction) which the cancellation signal handler can use to determine whether the interrupted code was in a cancellable state. these changes eliminate race conditions in the previous generation of cancellation handling code (whereby a cancellation request received just prior to the syscall would not be processed, leaving the syscall to block, potentially indefinitely), and remedy an issue where non-cancellable syscalls made from signal handlers became cancellable if the signal handler interrupted a cancellation point. x86_64 asm is untested and may need a second try to get it right.