diff options
| -rw-r--r-- | src/CMakeLists.txt | 29 | ||||
| -rw-r--r-- | src/sig-monitor.c | 259 | ||||
| -rw-r--r-- | src/sig-monitor.h | 2 |
3 files changed, 206 insertions, 84 deletions
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt index 2985db4b..1d5da5e8 100644 --- a/src/CMakeLists.txt +++ b/src/CMakeLists.txt @@ -24,6 +24,35 @@ ADD_DEFINITIONS(-DBINDING_INSTALL_DIR="${binding_install_dir}") # Always add INFER_EXTENSION (more details in afb-hreq.c) ADD_DEFINITIONS(-DINFER_EXTENSION) +############################################################################ +# TODO: improve below setting +set(USE_SIG_MONITOR_DUMPSTACK ON CACHE BOOL "activate dump stack on error") +set(USE_SIG_MONITOR_SIGNALS ON CACHE BOOL "activate handling of signals") +set(USE_SIG_MONITOR_FOR_CALL ON CACHE BOOL "activate monitoring of calls") +set(USE_SIG_MONITOR_TIMERS ON CACHE BOOL "activate monitoring of call expiration") + +if(USE_SIG_MONITOR_DUMPSTACK) + add_definitions(-DUSE_SIG_MONITOR_DUMPSTACK=1) +else() + add_definitions(-DUSE_SIG_MONITOR_DUMPSTACK=0) +endif() +if(USE_SIG_MONITOR_SIGNALS) + add_definitions(-DUSE_SIG_MONITOR_SIGNALS=1) +else() + add_definitions(-DUSE_SIG_MONITOR_SIGNALS=0) +endif() +if(USE_SIG_MONITOR_FOR_CALL) + add_definitions(-DUSE_SIG_MONITOR_FOR_CALL=1) +else() + add_definitions(-DUSE_SIG_MONITOR_FOR_CALL=0) +endif() +if(USE_SIG_MONITOR_TIMERS) + add_definitions(-DUSE_SIG_MONITOR_TIMERS=1) +else() + add_definitions(-DUSE_SIG_MONITOR_TIMERS=0) +endif() +############################################################################ + SET(AFB_LIB_SOURCES afb-api.c afb-api-so.c diff --git a/src/sig-monitor.c b/src/sig-monitor.c index 4bb69fe5..954dcf8b 100644 --- a/src/sig-monitor.c +++ b/src/sig-monitor.c @@ -17,34 +17,59 @@ #define _GNU_SOURCE +/******************************************************************************* +* sig-monitor is under the control of several compilation flags +*******************************************************************************/ + +/* controls whether to dump stack or not */ +#if !defined(USE_SIG_MONITOR_DUMPSTACK) +# define USE_SIG_MONITOR_DUMPSTACK 1 +#endif + +/* control whether to monitor signals */ +#if !defined(USE_SIG_MONITOR_SIGNALS) +# define USE_SIG_MONITOR_SIGNALS 1 +#endif + +/* controls whether to monitor calls */ +#if !defined(USE_SIG_MONITOR_FOR_CALL) +# define USE_SIG_MONITOR_FOR_CALL 1 +#endif + +/* control whether to monitor timers */ +#if !defined(USE_SIG_MONITOR_TIMERS) +# define USE_SIG_MONITOR_TIMERS 1 +#endif + +#if !USE_SIG_MONITOR_SIGNALS +# undef USE_SIG_MONITOR_FOR_CALL +# define USE_SIG_MONITOR_FOR_CALL 0 +#endif + +#if !USE_SIG_MONITOR_FOR_CALL +# undef USE_SIG_MONITOR_TIMERS +# define USE_SIG_MONITOR_TIMERS 0 +#endif + +/******************************************************************************/ + #include <stdlib.h> #include <stdio.h> -#include <signal.h> #include <string.h> -#include <setjmp.h> -#include <time.h> #include <unistd.h> -#include <sys/syscall.h> -#include <execinfo.h> #include "sig-monitor.h" + #include "verbose.h" -#define SIG_FOR_TIMER SIGVTALRM +/******************************************************************************/ +#if !USE_SIG_MONITOR_DUMPSTACK -/* local handler */ -static _Thread_local sigjmp_buf *error_handler; -static _Thread_local int in_safe_dumpstack; +static inline void dumpstack(int crop, int signum) {} -/* local timers */ -static _Thread_local int thread_timer_set; -static _Thread_local timer_t thread_timerid; +#else -/* internal signal lists */ -static int sigerr[] = { SIG_FOR_TIMER, SIGSEGV, SIGFPE, SIGILL, SIGBUS, 0 }; -static int sigterm[] = { SIGINT, SIGABRT, SIGTERM, 0 }; -static int exiting = 0; -static int enabled = 0; +#include <execinfo.h> /* * Dumps the current stack @@ -82,23 +107,28 @@ static void dumpstack(int crop, int signum) } } -static void safe_dumpstack_cb(int signum, void *closure) -{ - int *args = closure; - if (signum) - ERROR("Can't provide backtrace: raised signal %s", strsignal(signum)); - else - dumpstack(args[0], args[1]); -} +#endif +/******************************************************************************/ +#if !USE_SIG_MONITOR_TIMERS -static void safe_dumpstack(int crop, int signum) -{ - int args[2] = { crop + 3, signum }; +static inline int timeout_create() { return 0; } +static inline int timeout_arm(int timeout) { return 0; } +static inline void timeout_disarm() {} +static inline void timeout_delete() {} - in_safe_dumpstack = 1; - sig_monitor(0, safe_dumpstack_cb, args); - in_safe_dumpstack = 0; -} +#define SIG_FOR_TIMER 0 + +#else + +#include <time.h> +#include <sys/syscall.h> +#include <signal.h> + +#define SIG_FOR_TIMER SIGVTALRM + +/* local per thread timers */ +static _Thread_local int thread_timer_set; +static _Thread_local timer_t thread_timerid; /* * Creates a timer for the current thread @@ -166,9 +196,67 @@ static inline void timeout_delete() thread_timer_set = 0; } } +#endif +/******************************************************************************/ +#if !USE_SIG_MONITOR_FOR_CALL + +static inline void monitor_raise(int signum) {} + +#else + +#include <setjmp.h> + +/* local handler */ +static _Thread_local sigjmp_buf *error_handler; + +static void monitor(int timeout, void (*function)(int sig, void*), void *arg) +{ + volatile int signum, signum2; + sigjmp_buf jmpbuf, *older; + + older = error_handler; + signum = setjmp(jmpbuf); + if (signum == 0) { + error_handler = &jmpbuf; + if (timeout) { + timeout_create(); + timeout_arm(timeout); + } + function(0, arg); + } else { + signum2 = setjmp(jmpbuf); + if (signum2 == 0) + function(signum, arg); + } + if (timeout) + timeout_disarm(); + error_handler = older; +} + +static inline void monitor_raise(int signum) +{ + if (error_handler != NULL) + longjmp(*error_handler, signum); +} +#endif +/******************************************************************************/ +#if !USE_SIG_MONITOR_SIGNALS + +static inline int enable_signal_handling() { return 0; } + +#else + +#include <signal.h> + +/* internal signal lists */ +static int sigerr[] = { SIGSEGV, SIGFPE, SIGILL, SIGBUS, SIG_FOR_TIMER, 0 }; +static int sigterm[] = { SIGINT, SIGABRT, SIGTERM, 0 }; + +static int exiting = 0; +static int enabled = 0; /* install the handlers */ -static int install(void (*handler)(int), int *signals) +static int set_signals_handler(void (*handler)(int), int *signals) { int result = 1; struct sigaction sa; @@ -200,12 +288,40 @@ static void on_rescue_exit(int signum) */ static void safe_exit(int code) { - install(on_rescue_exit, sigerr); - install(on_rescue_exit, sigterm); + set_signals_handler(on_rescue_exit, sigerr); + set_signals_handler(on_rescue_exit, sigterm); exiting = code; exit(code); } +#if !USE_SIG_MONITOR_DUMPSTACK + +static inline void safe_dumpstack(int crop, int signum) {} +#define in_safe_dumpstack (0) + +#else + +static _Thread_local int in_safe_dumpstack; + +static void safe_dumpstack_cb(int signum, void *closure) +{ + int *args = closure; + if (signum) + ERROR("Can't provide backtrace: raised signal %s", strsignal(signum)); + else + dumpstack(args[0], args[1]); +} + +static void safe_dumpstack(int crop, int signum) +{ + int args[2] = { crop + 3, signum }; + + in_safe_dumpstack = 1; + sig_monitor(0, safe_dumpstack_cb, args); + in_safe_dumpstack = 0; +} +#endif + /* Handles signals that terminate the process */ static void on_signal_terminate (int signum) { @@ -220,42 +336,43 @@ static void on_signal_terminate (int signum) /* Handles monitored signals that can be continued */ static void on_signal_error(int signum) { - if (in_safe_dumpstack) - longjmp(*error_handler, signum); - - ERROR("ALERT! signal %d received: %s", signum, strsignal(signum)); - if (error_handler == NULL && signum == SIG_FOR_TIMER) - return; - - safe_dumpstack(3, signum); + if (!in_safe_dumpstack) { + ERROR("ALERT! signal %d received: %s", signum, strsignal(signum)); - // unlock signal to allow a new signal to come - if (error_handler != NULL) - longjmp(*error_handler, signum); + safe_dumpstack(3, signum); + } + monitor_raise(signum); - ERROR("Unmonitored signal %d received: %s", signum, strsignal(signum)); - safe_exit(2); + if (signum != SIG_FOR_TIMER) { + ERROR("Unmonitored signal %d received: %s", signum, strsignal(signum)); + safe_exit(2); + } } -void sig_monitor_disable() +/* +static void disable_signal_handling() { + set_signals_handler(SIG_DFL, sigerr); + set_signals_handler(SIG_DFL, sigterm); enabled = 0; - install(SIG_DFL, sigerr); - install(SIG_DFL, sigterm); } +*/ -int sig_monitor_enable() +static int enable_signal_handling() { - enabled = install(on_signal_error, sigerr) && install(on_signal_terminate, sigterm); - if (enabled) - return 0; - sig_monitor_disable(); - return -1; + if (!set_signals_handler(on_signal_error, sigerr) + || !set_signals_handler(on_signal_terminate, sigterm)) { + return -1; + } + enabled = 1; + return 0; } +#endif +/******************************************************************************/ int sig_monitor_init(int enable) { - return enable ? sig_monitor_enable() : (sig_monitor_disable(), 0); + return enable ? enable_signal_handling() : 0; } int sig_monitor_init_timeouts() @@ -268,35 +385,13 @@ void sig_monitor_clean_timeouts() timeout_delete(); } -static void monitor(int timeout, void (*function)(int sig, void*), void *arg) -{ - volatile int signum, signum2; - sigjmp_buf jmpbuf, *older; - - older = error_handler; - signum = setjmp(jmpbuf); - if (signum == 0) { - error_handler = &jmpbuf; - if (timeout) { - timeout_create(); - timeout_arm(timeout); - } - function(0, arg); - } else { - signum2 = setjmp(jmpbuf); - if (signum2 == 0) - function(signum, arg); - } - if (timeout) - timeout_disarm(); - error_handler = older; -} - void sig_monitor(int timeout, void (*function)(int sig, void*), void *arg) { +#if USE_SIG_MONITOR_SIGNALS && USE_SIG_MONITOR_FOR_CALL if (enabled) monitor(timeout, function, arg); else +#endif function(0, arg); } diff --git a/src/sig-monitor.h b/src/sig-monitor.h index 9e3792f5..09f648fb 100644 --- a/src/sig-monitor.h +++ b/src/sig-monitor.h @@ -20,8 +20,6 @@ extern int sig_monitor_init(int enable); extern void sig_monitor_clean_timeouts(); extern int sig_monitor_init_timeouts(); -extern void sig_monitor_disable(); -extern int sig_monitor_enable(); extern void sig_monitor(int timeout, void (*function)(int sig, void*), void *arg); |