musl/src/signal/siglongjmp.c

#include <setjmp.h>
#include <signal.h>
#include "syscall.h"
#include "pthread_impl.h"

_Noreturn void siglongjmp(sigjmp_buf buf, int ret)
{
	if (buf->__fl) __restore_sigs(buf->__ss);
	longjmp(buf, ret);
}
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`#include <setjmp.h>`
			`#include <signal.h>`
jmp_buf overhaul fixing several issues on arm, the location of the saved-signal-mask flag and mask were off by one between sigsetjmp and siglongjmp, causing incorrect behavior restoring the signal mask. this is because the siglongjmp code assumed an extra slot was in the non-sig jmp_buf for the flag, but arm did not have this. now, the extra slot is removed for all archs since it was useless. also, arm eabi requires jmp_buf to have 8-byte alignment. we achieve that using long long as the type rather than with non-portable gcc attribute tags. 2012-07-03 20:07:33 -04:00			`#include "syscall.h"`
transition to using functions for internal signal blocking/restoring there are several reasons for this change. one is getting rid of the repetition of the syscall signature all over the place. another is sharing the constant masks without costly GOT accesses in PIC. the main motivation, however, is accurately representing whether we want to block signals that might be handled by the application, or all signals. 2013-04-26 19:48:01 -04:00			`#include "pthread_impl.h"`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00
further use of _Noreturn, for non-plain-C functions note that POSIX does not specify these functions as _Noreturn, because POSIX is aligned with C99, not the new C11 standard. when POSIX is eventually updated to C11, it will almost surely give these functions the _Noreturn attribute. for now, the actual _Noreturn keyword is not used anyway when compiling with a c99 compiler, which is what POSIX requires; the GCC __attribute__ is used instead if it's available, however. in a few places, I've added infinite for loops at the end of _Noreturn functions to silence compiler warnings. presumably __buildin_unreachable could achieve the same thing, but it would only work on newer GCCs and would not be portable. the loops should have near-zero code size cost anyway. like the previous _Noreturn commit, this one is based on patches contributed by philomath. 2012-09-06 23:34:10 -04:00			`_Noreturn void siglongjmp(sigjmp_buf buf, int ret)`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`{`
transition to using functions for internal signal blocking/restoring there are several reasons for this change. one is getting rid of the repetition of the syscall signature all over the place. another is sharing the constant masks without costly GOT accesses in PIC. the main motivation, however, is accurately representing whether we want to block signals that might be handled by the application, or all signals. 2013-04-26 19:48:01 -04:00			`if (buf->__fl) __restore_sigs(buf->__ss);`
change jmp_buf to share an underlying type and struct tag with sigjmp_buf this is necessary to meet the C++ ABI target. alternatives were considered to avoid the size increase for non-sig jmp_buf objects, but they seemed to have worse properties. moreover, the relative size increase is only extreme on x86[_64]; one way of interpreting this is that, if the size increase from this patch makes jmp_buf use too much memory, then the program was already using too much memory when built for non-x86 archs. 2013-07-24 02:17:02 -04:00			`longjmp(buf, ret);`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`}`