diff options
Diffstat (limited to 'common/signal.c')
| -rw-r--r-- | common/signal.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/common/signal.c b/common/signal.c new file mode 100644 index 000000000..0c79214b2 --- /dev/null +++ b/common/signal.c @@ -0,0 +1,259 @@ +/* signal.c - signal handling + * Copyright (C) 1998, 1999, 2000, 2001, 2002, + * 2005 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, + * USA. + */ + +#include <config.h> +#include <stdio.h> +#include <stdlib.h> +#include <signal.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <assert.h> + +#include "util.h" + + +#ifndef HAVE_DOSISH_SYSTEM +static volatile int caught_fatal_sig; +static volatile int caught_sigusr1; +#endif +static void (*cleanup_fnc)(void); + + +#ifndef HAVE_DOSISH_SYSTEM +static void +init_one_signal (int sig, RETSIGTYPE (*handler)(int), int check_ign ) +{ +# ifdef HAVE_SIGACTION + struct sigaction oact, nact; + + if (check_ign) + { + /* we don't want to change an IGN handler */ + sigaction (sig, NULL, &oact ); + if (oact.sa_handler == SIG_IGN ) + return; + } + + nact.sa_handler = handler; + sigemptyset (&nact.sa_mask); + nact.sa_flags = 0; + sigaction ( sig, &nact, NULL); +# else + RETSIGTYPE (*ohandler)(int); + + ohandler = signal (sig, handler); + if (check_ign && ohandler == SIG_IGN) + { + /* Change it back if it was already set to IGN */ + signal (sig, SIG_IGN); + } +# endif +} +#endif /*!HAVE_DOSISH_SYSTEM*/ + +#ifndef HAVE_DOSISH_SYSTEM +static const char * +get_signal_name( int signum ) +{ + /* Note that we can't use strsignal(), because it is not + reentrant. */ +#if HAVE_DECL_SYS_SIGLIST && defined(NSIG) + return (signum >= 0 && signum < NSIG) ? sys_siglist[signum] : "?"; +#else + return NULL; +#endif +} +#endif /*!HAVE_DOSISH_SYSTEM*/ + +#ifndef HAVE_DOSISH_SYSTEM +static RETSIGTYPE +got_fatal_signal (int sig) +{ + const char *s; + + if (caught_fatal_sig) + raise (sig); + caught_fatal_sig = 1; + + if (cleanup_fnc) + cleanup_fnc (); + /* Better don't translate these messages. */ + write (2, "\n", 1 ); + s = log_get_prefix (NULL); + if (s) + write(2, s, strlen (s)); + write (2, ": signal ", 9 ); + s = get_signal_name(sig); + if (s) + write (2, s, strlen(s) ); + else + { + /* We are in a signal handler so we can't use any kind of printf + even not sprintf. USe a straightforward algorithm. */ + if (sig < 0 || sig >= 100000) + write (2, "?", 1); + else + { + int i, any=0; + + for (i=10000; i; i /= 10) + { + if (sig >= i || ((any || i==1) && !(sig/i))) + { + write (2, "0123456789"+(sig/i), 1); + if ((sig/i)) + any = 1; + sig %= i; + } + } + } + } + write (2, " caught ... exiting\n", 20); + + /* Reset action to default action and raise signal again */ + init_one_signal (sig, SIG_DFL, 0); + /* Fixme: remove_lockfiles ();*/ +#ifdef __riscos__ + close_fds (); +#endif /* __riscos__ */ + raise( sig ); +} +#endif /*!HAVE_DOSISH_SYSTEM*/ + +#ifndef HAVE_DOSISH_SYSTEM +static RETSIGTYPE +got_usr_signal (int sig) +{ + caught_sigusr1 = 1; +} +#endif /*!HAVE_DOSISH_SYSTEM*/ + +void +gnupg_init_signals (int mode, void (*fast_cleanup)(void)) +{ + assert (!mode); + + cleanup_fnc = fast_cleanup; +#ifndef HAVE_DOSISH_SYSTEM + init_one_signal (SIGINT, got_fatal_signal, 1 ); + init_one_signal (SIGHUP, got_fatal_signal, 1 ); + init_one_signal (SIGTERM, got_fatal_signal, 1 ); + init_one_signal (SIGQUIT, got_fatal_signal, 1 ); + init_one_signal (SIGSEGV, got_fatal_signal, 1 ); + init_one_signal (SIGUSR1, got_usr_signal, 0 ); + init_one_signal (SIGPIPE, SIG_IGN, 0 ); +#endif +} + +void +gnupg_pause_on_sigusr (int which) +{ +#ifndef HAVE_DOSISH_SYSTEM +# ifdef HAVE_SIGPROCMASK + sigset_t mask, oldmask; + + assert (which == 1); + sigemptyset( &mask ); + sigaddset( &mask, SIGUSR1 ); + + sigprocmask( SIG_BLOCK, &mask, &oldmask ); + while (!caught_sigusr1) + sigsuspend (&oldmask); + caught_sigusr1 = 0; + sigprocmask (SIG_UNBLOCK, &mask, NULL); +# else + assert (which == 1); + sighold (SIGUSR1); + while (!caught_sigusr1) + sigpause(SIGUSR1); + caught_sigusr1 = 0; + sigrelease(SIGUSR1); +# endif /*!HAVE_SIGPROCMASK*/ +#endif +} + + +static void +do_block( int block ) +{ +#ifndef HAVE_DOSISH_SYSTEM + static int is_blocked; +#ifdef HAVE_SIGPROCMASK + static sigset_t oldmask; + + if (block) + { + sigset_t newmask; + + if (is_blocked) + log_bug ("signals are already blocked\n"); + sigfillset( &newmask ); + sigprocmask( SIG_BLOCK, &newmask, &oldmask ); + is_blocked = 1; + } + else + { + if (!is_blocked) + log_bug("signals are not blocked\n"); + sigprocmask (SIG_SETMASK, &oldmask, NULL); + is_blocked = 0; + } +#else /*!HAVE_SIGPROCMASK*/ + static void (*disposition[MAXSIG])(); + int sig; + + if (block) + { + if (is_blocked) + log_bug("signals are already blocked\n"); + for (sig=1; sig < MAXSIG; sig++) + { + disposition[sig] = sigset (sig, SIG_HOLD); + } + is_blocked = 1; + } + else + { + if (!is_blocked) + log_bug ("signals are not blocked\n"); + for (sig=1; sig < MAXSIG; sig++) { + sigset (sig, disposition[sig]); + } + is_blocked = 0; + } +#endif /*!HAVE_SIGPROCMASK*/ +#endif /*HAVE_DOSISH_SYSTEM*/ +} + + +void +gnupg_block_all_signals () +{ + do_block(1); +} + +void +gnupg_unblock_all_signals () +{ + do_block(0); +} |