git/sigchain.h

#ifndef SIGCHAIN_H
#define SIGCHAIN_H

typedef void (*sigchain_fun)(int);

int sigchain_push(int sig, sigchain_fun f);
int sigchain_pop(int sig);

#endif /* SIGCHAIN_H */
chain kill signals for cleanup functions If a piece of code wanted to do some cleanup before exiting (e.g., cleaning up a lockfile or a tempfile), our usual strategy was to install a signal handler that did something like this: do_cleanup(); /* actual work / signal(signo, SIG_DFL); / restore previous behavior / raise(signo); / deliver signal, killing ourselves */ For a single handler, this works fine. However, if we want to clean up two _different_ things, we run into a problem. The most recently installed handler will run, but when it removes itself as a handler, it doesn't put back the first handler. This patch introduces sigchain, a tiny library for handling a stack of signal handlers. You sigchain_push each handler, and use sigchain_pop to restore whoever was before you in the stack. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com> 2009-01-22 14:02:35 +08:00			`#ifndef SIGCHAIN_H`
			`#define SIGCHAIN_H`

			`typedef void (*sigchain_fun)(int);`

			`int sigchain_push(int sig, sigchain_fun f);`
			`int sigchain_pop(int sig);`

			`#endif /* SIGCHAIN_H */`