diff options
Diffstat (limited to 'cpukit/posix/src/psignal.c')
| -rw-r--r-- | cpukit/posix/src/psignal.c | 1347 |
1 files changed, 1347 insertions, 0 deletions
diff --git a/cpukit/posix/src/psignal.c b/cpukit/posix/src/psignal.c new file mode 100644 index 0000000000..289c9f02d5 --- /dev/null +++ b/cpukit/posix/src/psignal.c @@ -0,0 +1,1347 @@ +/* + * $Id$ + */ + +#include <assert.h> +#include <errno.h> +#include <pthread.h> +#include <signal.h> + +#include <rtems/system.h> +#include <rtems/score/isr.h> +#include <rtems/score/thread.h> +#include <rtems/score/tqdata.h> +#include <rtems/score/wkspace.h> +#include <rtems/posix/seterr.h> +#include <rtems/posix/threadsup.h> +#include <rtems/posix/pthread.h> +#include <rtems/posix/time.h> + +/* + * Currently 32 signals numbered 1-32 are defined + */ + +#define SIGNAL_EMPTY_MASK 0x00000000 +#define SIGNAL_ALL_MASK 0xffffffff + +#define signo_to_mask( _sig ) (1 << ((_sig) - 1)) + +#define is_valid_signo( _sig ) \ + ((_sig) >= 1 && (_sig) <= 32 ) + +/*** PROCESS WIDE STUFF ****/ + +sigset_t _POSIX_signals_Pending; + +void _POSIX_signals_Abormal_termination_handler( int signo ) +{ + exit( 1 ); +} + +#define _POSIX_signals_Stop_handler NULL +#define _POSIX_signals_Continue_handler NULL + +#define SIGACTION_TERMINATE \ + { 0, SIGNAL_ALL_MASK, {_POSIX_signals_Abormal_termination_handler} } +#define SIGACTION_IGNORE \ + { 0, SIGNAL_ALL_MASK, {SIG_IGN} } +#define SIGACTION_STOP \ + { 0, SIGNAL_ALL_MASK, {_POSIX_signals_Stop_handler} } +#define SIGACTION_CONTINUE \ + { 0, SIGNAL_ALL_MASK, {_POSIX_signals_Continue_handler} } + +#define SIG_ARRAY_MAX (SIGRTMAX + 1) +struct sigaction _POSIX_signals_Default_vectors[ SIG_ARRAY_MAX ] = { + /* NO SIGNAL 0 */ SIGACTION_IGNORE, + /* SIGHUP 1 */ SIGACTION_TERMINATE, + /* SIGINT 2 */ SIGACTION_TERMINATE, + /* SIGQUIT 3 */ SIGACTION_TERMINATE, + /* SIGILL 4 */ SIGACTION_TERMINATE, + /* SIGTRAP 5 */ SIGACTION_TERMINATE, + /* SIGIOT 6 */ SIGACTION_TERMINATE, + /* SIGABRT 6 SIGACTION_TERMINATE, -- alias for SIGIOT */ + /* SIGEMT 7 */ SIGACTION_TERMINATE, + /* SIGFPE 8 */ SIGACTION_TERMINATE, + /* SIGKILL 9 */ SIGACTION_TERMINATE, + /* SIGBUS 10 */ SIGACTION_TERMINATE, + /* SIGSEGV 11 */ SIGACTION_TERMINATE, + /* SIGSYS 12 */ SIGACTION_TERMINATE, + /* SIGPIPE 13 */ SIGACTION_TERMINATE, + /* SIGALRM 14 */ SIGACTION_TERMINATE, + /* SIGTERM 15 */ SIGACTION_TERMINATE, + /* SIGUSR1 16 */ SIGACTION_TERMINATE, + /* SIGUSR2 17 */ SIGACTION_TERMINATE, + /* SIGRTMIN 18 */ SIGACTION_IGNORE, + /* SIGRT 19 */ SIGACTION_IGNORE, + /* SIGRT 20 */ SIGACTION_IGNORE, + /* SIGRT 21 */ SIGACTION_IGNORE, + /* SIGRT 22 */ SIGACTION_IGNORE, + /* SIGRT 23 */ SIGACTION_IGNORE, + /* SIGRT 24 */ SIGACTION_IGNORE, + /* SIGRT 25 */ SIGACTION_IGNORE, + /* SIGRT 26 */ SIGACTION_IGNORE, + /* SIGRT 27 */ SIGACTION_IGNORE, + /* SIGRT 28 */ SIGACTION_IGNORE, + /* SIGRT 29 */ SIGACTION_IGNORE, + /* SIGRT 30 */ SIGACTION_IGNORE, + /* SIGRT 31 */ SIGACTION_IGNORE, + /* SIGRTMAX 32 */ SIGACTION_IGNORE +}; + +struct sigaction _POSIX_signals_Vectors[ SIG_ARRAY_MAX ]; + +Watchdog_Control _POSIX_signals_Alarm_timer; + +Thread_queue_Control _POSIX_signals_Wait_queue; + +typedef struct { + Chain_Node Node; + siginfo_t Info; +} POSIX_signals_Siginfo_node; + +Chain_Control _POSIX_signals_Inactive_siginfo; +Chain_Control _POSIX_signals_Siginfo[ SIG_ARRAY_MAX ]; + +/*PAGE + * + * XXX - move these + */ + +#define _States_Is_interruptible_signal( _states ) \ + ( ((_states) & \ + (STATES_WAITING_FOR_SIGNAL|STATES_INTERRUPTIBLE_BY_SIGNAL)) == \ + (STATES_WAITING_FOR_SIGNAL|STATES_INTERRUPTIBLE_BY_SIGNAL)) + +/*PAGE + * + * _POSIX_signals_Unblock_thread + */ + +/* XXX this routine could probably be cleaned up */ +boolean _POSIX_signals_Unblock_thread( + Thread_Control *the_thread, + int signo, + siginfo_t *info +) +{ + POSIX_API_Control *api; + sigset_t mask; + siginfo_t *the_info = NULL; + + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + + mask = signo_to_mask( signo ); + + /* + * Is the thread is specifically waiting for a signal? + */ + + if ( _States_Is_interruptible_signal( the_thread->current_state ) ) { + + if ( (the_thread->Wait.option & mask) || (~api->signals_blocked & mask) ) { + the_thread->Wait.return_code = EINTR; + + the_info = (siginfo_t *) the_thread->Wait.return_argument; + + if ( !info ) { + the_info->si_signo = signo; + the_info->si_code = SI_USER; + the_info->si_value.sival_int = 0; + } else { + *the_info = *info; + } + + _Thread_queue_Extract_with_proxy( the_thread ); + return TRUE; + } + + /* + * This should only be reached via pthread_kill(). + */ + + return FALSE; + } + + if ( ~api->signals_blocked & mask ) { + the_thread->do_post_task_switch_extension = TRUE; + + if ( the_thread->current_state & STATES_INTERRUPTIBLE_BY_SIGNAL ) { + the_thread->Wait.return_code = EINTR; + if ( _States_Is_waiting_on_thread_queue(the_thread->current_state) ) + _Thread_queue_Extract_with_proxy( the_thread ); + else if ( _States_Is_delaying(the_thread->current_state)){ + if ( _Watchdog_Is_active( &the_thread->Timer ) ) + (void) _Watchdog_Remove( &the_thread->Timer ); + _Thread_Unblock( the_thread ); + } + } + } + return FALSE; + +} + +/*PAGE + * + * _POSIX_signals_Set_process_signals + */ + +void _POSIX_signals_Set_process_signals( + sigset_t mask +) +{ + ISR_Level level; + + _ISR_Disable( level ); + if ( !_POSIX_signals_Pending ) + _Thread_Do_post_task_switch_extension++; + _POSIX_signals_Pending |= mask; + _ISR_Enable( level ); +} + +/*PAGE + * + * _POSIX_signals_Clear_process_signals + */ + +void _POSIX_signals_Clear_process_signals( + sigset_t mask +) +{ + ISR_Level level; + + _ISR_Disable( level ); + _POSIX_signals_Pending &= ~mask; + if ( !_POSIX_signals_Pending ) + _Thread_Do_post_task_switch_extension--; + _ISR_Enable( level ); +} + +/*PAGE + * + * _POSIX_signals_Clear_signals + */ + +boolean _POSIX_signals_Clear_signals( + POSIX_API_Control *api, + int signo, + siginfo_t *info, + boolean is_global, + boolean check_blocked +) +{ + sigset_t mask; + sigset_t signals_blocked; + ISR_Level level; + boolean do_callout; + POSIX_signals_Siginfo_node *psiginfo; + + mask = signo_to_mask( signo ); + + do_callout = FALSE; + + /* set blocked signals based on if checking for them, SIGNAL_ALL_MASK + * insures that no signals are blocked and all are checked. + */ + + if ( check_blocked ) + signals_blocked = ~api->signals_blocked; + else + signals_blocked = SIGNAL_ALL_MASK; + + /* XXX this is not right for siginfo type signals yet */ + /* XXX since they can't be cleared the same way */ + + _ISR_Disable( level ); + if ( is_global ) { + if ( mask & (_POSIX_signals_Pending & signals_blocked) ) { + if ( _POSIX_signals_Vectors[ signo ].sa_flags == SA_SIGINFO ) { + psiginfo = (POSIX_signals_Siginfo_node *) + _Chain_Get_unprotected( &_POSIX_signals_Siginfo[ signo ] ); + if ( _Chain_Is_empty( &_POSIX_signals_Siginfo[ signo ] ) ) + _POSIX_signals_Clear_process_signals( mask ); + if ( psiginfo ) { + *info = psiginfo->Info; + _Chain_Append_unprotected( + &_POSIX_signals_Inactive_siginfo, + &psiginfo->Node + ); + } else + do_callout = FALSE; + } else + _POSIX_signals_Clear_process_signals( mask ); + do_callout = TRUE; + } + } else { + if ( mask & (api->signals_pending & signals_blocked) ) { + api->signals_pending &= ~mask; + do_callout = TRUE; + } + } + _ISR_Enable( level ); + return do_callout; +} + + +/*PAGE + * + * _POSIX_signals_Check_signal + */ + +boolean _POSIX_signals_Check_signal( + POSIX_API_Control *api, + int signo, + boolean is_global +) +{ + siginfo_t siginfo_struct; + sigset_t saved_signals_blocked; + + if ( ! _POSIX_signals_Clear_signals( api, signo, &siginfo_struct, + is_global, TRUE ) ) + return FALSE; + + /* + * Since we made a union of these, only one test is necessary but this is + * safer. + */ + + assert( _POSIX_signals_Vectors[ signo ].sa_handler || + _POSIX_signals_Vectors[ signo ].sa_sigaction ); + + /* + * Just to prevent sending a signal which is currently being ignored. + */ + + if ( _POSIX_signals_Vectors[ signo ].sa_handler == SIG_IGN ) + return FALSE; + + /* + * Block the signals requested in sa_mask + */ + + saved_signals_blocked = api->signals_blocked; + api->signals_blocked |= _POSIX_signals_Vectors[ signo ].sa_mask; + + switch ( _POSIX_signals_Vectors[ signo ].sa_flags ) { + case SA_SIGINFO: + assert( is_global ); + + (*_POSIX_signals_Vectors[ signo ].sa_sigaction)( + signo, + &siginfo_struct, + NULL /* context is undefined per 1003.1b-1993, p. 66 */ + ); + break; + default: + (*_POSIX_signals_Vectors[ signo ].sa_handler)( signo ); + break; + } + + /* + * Restore the previous set of blocked signals + */ + + api->signals_blocked = saved_signals_blocked; + + return TRUE; +} + +void _POSIX_signals_Post_switch_extension( + Thread_Control *the_thread +) +{ + POSIX_API_Control *api; + int signo; + ISR_Level level; + + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + + /* + * If we invoke any user code, there is the possibility that + * a new signal has been posted that we should process so we + * restart the loop if a signal handler was invoked. + * + * The first thing done is to check there are any signals to be + * processed at all. No point in doing this loop otherwise. + */ + +restart: + _ISR_Disable( level ); + if ( !(~api->signals_blocked & + (api->signals_pending | _POSIX_signals_Pending)) ) { + _ISR_Enable( level ); + return; + } + _ISR_Enable( level ); + + for ( signo = SIGRTMIN ; signo <= SIGRTMAX ; signo++ ) { + + if ( _POSIX_signals_Check_signal( api, signo, FALSE ) ) + goto restart; + + if ( _POSIX_signals_Check_signal( api, signo, TRUE ) ) + goto restart; + + } + +/* XXX - add __SIGFIRSTNOTRT or something like that to newlib siginfo.h */ + + for ( signo = SIGHUP ; signo <= __SIGLASTNOTRT ; signo++ ) { + + if ( _POSIX_signals_Check_signal( api, signo, FALSE ) ) + goto restart; + + if ( _POSIX_signals_Check_signal( api, signo, TRUE ) ) + goto restart; + + } + +} + +/*PAGE + * + * _POSIX_signals_Alarm_TSR + */ + +void _POSIX_signals_Alarm_TSR( + Objects_Id id, + void *argument +) +{ + int status; + + status = kill( getpid(), SIGALRM ); + /* XXX can't print from an ISR, should this be fatal? */ + assert( !status ); +} + +/*PAGE + * + * _POSIX_signals_Manager_Initialization + */ + +void _POSIX_signals_Manager_Initialization( + int maximum_queued_signals +) +{ + unsigned32 signo; + + /* + * Insure we have the same number of vectors and default vector entries + */ + + assert( + sizeof(_POSIX_signals_Vectors) == sizeof(_POSIX_signals_Default_vectors) + ); + + memcpy( + _POSIX_signals_Vectors, + _POSIX_signals_Default_vectors, + sizeof( _POSIX_signals_Vectors ) + ); + + /* + * Initialize the set of pending signals for the entire process + */ + + sigemptyset( &_POSIX_signals_Pending ); + + /* + * Initialize the timer used to implement alarm(). + */ + + _Watchdog_Initialize( + &_POSIX_signals_Alarm_timer, + _POSIX_signals_Alarm_TSR, + 0, + NULL + ); + + /* + * Initialize the queue we use to block for signals + */ + + _Thread_queue_Initialize( + &_POSIX_signals_Wait_queue, + OBJECTS_NO_CLASS, + THREAD_QUEUE_DISCIPLINE_PRIORITY, + STATES_WAITING_FOR_SIGNAL | STATES_INTERRUPTIBLE_BY_SIGNAL, + NULL, + EAGAIN + ); + + /* XXX status codes */ + + /* + * Allocate the siginfo pools. + */ + + for ( signo=1 ; signo<= SIGRTMAX ; signo++ ) + _Chain_Initialize_empty( &_POSIX_signals_Siginfo[ signo ] ); + + _Chain_Initialize( + &_POSIX_signals_Inactive_siginfo, + _Workspace_Allocate_or_fatal_error( + maximum_queued_signals * sizeof( POSIX_signals_Siginfo_node ) + ), + maximum_queued_signals, + sizeof( POSIX_signals_Siginfo_node ) + ); +} + +/* + * 3.3.3 Manipulate Signal Sets, P1003.1b-1993, p. 69 + */ + +int sigemptyset( + sigset_t *set +) +{ + if ( !set ) + set_errno_and_return_minus_one( EINVAL ); + + *set = 0; + return 0; +} + +/* + * 3.3.3 Manipulate Signal Sets, P1003.1b-1993, p. 69 + */ + +int sigfillset( + sigset_t *set +) +{ + if ( !set ) + set_errno_and_return_minus_one( EINVAL ); + + *set = SIGNAL_ALL_MASK; + return 0; +} + +/* + * 3.3.3 Manipulate Signal Sets, P1003.1b-1993, p. 69 + */ + +int sigaddset( + sigset_t *set, + int signo +) +{ + if ( !set ) + set_errno_and_return_minus_one( EINVAL ); + + if ( !signo ) + return 0; + + if ( !is_valid_signo(signo) ) + set_errno_and_return_minus_one( EINVAL ); + + *set |= signo_to_mask(signo); + return 0; +} + +/* + * 3.3.3 Manipulate Signal Sets, P1003.1b-1993, p. 69 + */ + +int sigdelset( + sigset_t *set, + int signo +) +{ + if ( !set ) + set_errno_and_return_minus_one( EINVAL ); + + if ( !signo ) + return 0; + + if ( !is_valid_signo(signo) ) + set_errno_and_return_minus_one( EINVAL ); + + *set &= ~signo_to_mask(signo); + return 0; +} + +/* + * 3.3.3 Manipulate Signal Sets, P1003.1b-1993, p. 69 + */ + +int sigismember( + const sigset_t *set, + int signo +) +{ + if ( !set ) + set_errno_and_return_minus_one( EINVAL ); + + if ( !signo ) + return 0; + + if ( !is_valid_signo(signo) ) + set_errno_and_return_minus_one( EINVAL ); + + if ( *set & signo_to_mask(signo) ) + return 1; + + return 0; +} + +/* + * 3.3.4 Examine and Change Signal Action, P1003.1b-1993, p. 70 + */ + +int sigaction( + int sig, + const struct sigaction *act, + struct sigaction *oact +) +{ + ISR_Level level; + + if ( oact ) + *oact = _POSIX_signals_Vectors[ sig ]; + + if ( !sig ) + return 0; + + if ( !is_valid_signo(sig) ) + set_errno_and_return_minus_one( EINVAL ); + + /* + * Some signals cannot be ignored (P1003.1b-1993, pp. 70-72 and references. + * + * NOTE: Solaris documentation claims to "silently enforce" this which + * contradicts the POSIX specification. + */ + + if ( sig == SIGKILL ) + set_errno_and_return_minus_one( EINVAL ); + + /* + * Evaluate the new action structure and set the global signal vector + * appropriately. + */ + + if ( act ) { + + /* + * Unless the user is installing the default signal actions, then + * we can just copy the provided sigaction structure into the vectors. + */ + + _ISR_Disable( level ); + if ( act->sa_handler == SIG_DFL ) { + _POSIX_signals_Vectors[ sig ] = _POSIX_signals_Default_vectors[ sig ]; + } else { + _POSIX_signals_Clear_process_signals( signo_to_mask(sig) ); + _POSIX_signals_Vectors[ sig ] = *act; + } + _ISR_Enable( level ); + } + + /* + * No need to evaluate or dispatch because: + * + * + If we were ignoring the signal before, none could be pending + * now (signals not posted when SIG_IGN). + * + If we are now ignoring a signal that was previously pending, + * we clear the pending signal indicator. + */ + + return 0; +} + +/* + * 3.3.5 Examine and Change Blocked Signals, P1003.1b-1993, p. 73 + * + * NOTE: P1003.1c/D10, p. 37 adds pthread_sigmask(). + * + */ + +int sigprocmask( + int how, + const sigset_t *set, + sigset_t *oset +) +{ + /* + * P1003.1c/Draft 10, p. 38 maps sigprocmask to pthread_sigmask. + */ + + return pthread_sigmask( how, set, oset ); +} + +/* + * 3.3.5 Examine and Change Blocked Signals, P1003.1b-1993, p. 73 + * + * NOTE: P1003.1c/D10, p. 37 adds pthread_sigmask(). + */ + +int pthread_sigmask( + int how, + const sigset_t *set, + sigset_t *oset +) +{ + POSIX_API_Control *api; + + if ( !set && !oset ) + set_errno_and_return_minus_one( EINVAL ); + + api = _Thread_Executing->API_Extensions[ THREAD_API_POSIX ]; + + if ( oset ) + *oset = api->signals_blocked; + + if ( !set ) + return 0; + + switch ( how ) { + case SIG_BLOCK: + api->signals_blocked |= *set; + break; + case SIG_UNBLOCK: + api->signals_blocked &= ~*set; + break; + case SIG_SETMASK: + api->signals_blocked = *set; + break; + default: + set_errno_and_return_minus_one( EINVAL ); + } + + /* XXX are there critical section problems here? */ + + /* XXX evaluate the new set */ + + if ( ~api->signals_blocked & + (api->signals_pending | _POSIX_signals_Pending) ) { + _Thread_Executing->do_post_task_switch_extension = TRUE; + _Thread_Dispatch(); + } + + return 0; +} + +/* + * 3.3.6 Examine Pending Signals, P1003.1b-1993, p. 75 + */ + +int sigpending( + sigset_t *set +) +{ + POSIX_API_Control *api; + + if ( !set ) + set_errno_and_return_minus_one( EINVAL ); + + api = _Thread_Executing->API_Extensions[ THREAD_API_POSIX ]; + + *set = api->signals_pending | _POSIX_signals_Pending; + + return 0; +} + +/* + * 3.3.7 Wait for a Signal, P1003.1b-1993, p. 75 + */ + +int sigsuspend( + const sigset_t *sigmask +) +{ + sigset_t saved_signals_blocked; + sigset_t all_signals; + int status; + POSIX_API_Control *api; + + api = _Thread_Executing->API_Extensions[ THREAD_API_POSIX ]; + + status = sigprocmask( SIG_BLOCK, sigmask, &saved_signals_blocked ); + + (void) sigfillset( &all_signals ); + + status = sigtimedwait( &all_signals, NULL, NULL ); + + (void) sigprocmask( SIG_SETMASK, &saved_signals_blocked, NULL ); + + return status; +} + +/* + * 3.3.8 Synchronously Accept a Signal, P1003.1b-1993, p. 76 + * + * NOTE: P1003.1c/D10, p. 39 adds sigwait(). + */ + +int sigwaitinfo( + const sigset_t *set, + siginfo_t *info +) +{ + return sigtimedwait( set, info, NULL ); +} + +/* + * 3.3.8 Synchronously Accept a Signal, P1003.1b-1993, p. 76 + * + * NOTE: P1003.1c/D10, p. 39 adds sigwait(). + */ + +int _POSIX_signals_Get_highest( + sigset_t set +) +{ + int signo; + + for ( signo = SIGRTMIN ; signo <= SIGRTMAX ; signo++ ) { + if ( set & signo_to_mask( signo ) ) + return signo; + } + +/* XXX - add __SIGFIRSTNOTRT or something like that to newlib siginfo.h */ + + for ( signo = SIGHUP ; signo <= __SIGLASTNOTRT ; signo++ ) { + if ( set & signo_to_mask( signo ) ) + return signo; + } + + return 0; +} + +int sigtimedwait( + const sigset_t *set, + siginfo_t *info, + const struct timespec *timeout +) +{ + Thread_Control *the_thread; + POSIX_API_Control *api; + Watchdog_Interval interval; + siginfo_t signal_information; + siginfo_t *the_info; + int signo; + + the_info = ( info ) ? info : &signal_information; + + the_thread = _Thread_Executing; + + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + + /* + * What if they are already pending? + */ + + /* API signals pending? */ + + if ( *set & api->signals_pending ) { + /* XXX real info later */ + the_info->si_signo = _POSIX_signals_Get_highest( api->signals_pending ); + _POSIX_signals_Clear_signals( api, the_info->si_signo, the_info, + FALSE, FALSE ); + the_info->si_code = SI_USER; + the_info->si_value.sival_int = 0; + return the_info->si_signo; + } + + /* Process pending signals? */ + + if ( *set & _POSIX_signals_Pending) { + signo = _POSIX_signals_Get_highest( _POSIX_signals_Pending ); + _POSIX_signals_Clear_signals( api, signo, the_info, TRUE, FALSE ); + + if ( !info ) { + the_info->si_signo = signo; + the_info->si_code = SI_USER; + the_info->si_value.sival_int = 0; + } + } + + interval = 0; + if ( timeout ) { + + if (timeout->tv_nsec < 0 || timeout->tv_nsec >= TOD_NANOSECONDS_PER_SECOND) + set_errno_and_return_minus_one( EINVAL ); + + interval = _POSIX_Timespec_to_interval( timeout ); + } + + the_info->si_signo = -1; + + _Thread_Disable_dispatch(); + the_thread->Wait.queue = &_POSIX_signals_Wait_queue; + the_thread->Wait.return_code = EINTR; + the_thread->Wait.option = *set; + the_thread->Wait.return_argument = (void *) the_info; + _Thread_queue_Enter_critical_section( &_POSIX_signals_Wait_queue ); + _Thread_queue_Enqueue( &_POSIX_signals_Wait_queue, interval ); + _Thread_Enable_dispatch(); + + errno = _Thread_Executing->Wait.return_code; + return the_info->si_signo; +} + +/* + * 3.3.8 Synchronously Accept a Signal, P1003.1b-1993, p. 76 + * + * NOTE: P1003.1c/D10, p. 39 adds sigwait(). + */ + +int sigwait( + const sigset_t *set, + int *sig +) +{ + int status; + + status = sigtimedwait( set, NULL, NULL ); + + if ( status != -1 ) { + if ( sig ) + *sig = status; + return 0; + } + + return errno; +} + +/*PAGE + * + * 3.3.2 Send a Signal to a Process, P1003.1b-1993, p. 68 + * + * NOTE: Behavior of kill() depends on _POSIX_SAVED_IDS. + */ + +#define _POSIX_signals_Is_interested( _api, _mask ) \ + ( ~(_api)->signals_blocked & (_mask) ) + +int killinfo( + pid_t pid, + int sig, + const union sigval *value +) +{ + sigset_t mask; + POSIX_API_Control *api; + unsigned32 the_class; + unsigned32 index; + unsigned32 maximum; + Objects_Information *the_info; + Objects_Control **object_table; + Thread_Control *the_thread; + Thread_Control *interested_thread; + Priority_Control interested_priority; + Chain_Control *the_chain; + Chain_Node *the_node; + siginfo_t siginfo_struct; + siginfo_t *siginfo; + POSIX_signals_Siginfo_node *psiginfo; + + /* + * Only supported for the "calling process" (i.e. this node). + */ + + if( pid != getpid() ) + set_errno_and_return_minus_one( ESRCH ); + + /* + * Validate the signal passed if not 0. + */ + + if ( sig && !is_valid_signo(sig) ) + set_errno_and_return_minus_one( EINVAL ); + + /* + * If the signal is being ignored, then we are out of here. + */ + + if ( !sig || _POSIX_signals_Vectors[ sig ].sa_handler == SIG_IGN ) + return 0; + + /* + * P1003.1c/Draft 10, p. 33 says that certain signals should always + * be directed to the executing thread such as those caused by hardware + * faults. + */ + + switch ( sig ) { + case SIGFPE: + case SIGILL: + case SIGSEGV: + return pthread_kill( pthread_self(), sig ); + default: + break; + } + + mask = signo_to_mask( sig ); + + /* + * Build up a siginfo structure + */ + + siginfo = &siginfo_struct; + siginfo->si_signo = sig; + siginfo->si_code = SI_USER; + if ( !value ) { + siginfo->si_value.sival_int = 0; + } else { + siginfo->si_value = *value; + } + + _Thread_Disable_dispatch(); + + /* + * Is the currently executing thread interested? If so then it will + * get it an execute it as soon as the dispatcher executes. + */ + + the_thread = _Thread_Executing; + + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + if ( _POSIX_signals_Is_interested( api, mask ) ) { + goto process_it; + } + + /* + * Is an interested thread waiting for this signal (sigwait())? + */ + + /* XXX violation of visibility -- need to define thread queue support */ + + for( index=0 ; + index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ; + index++ ) { + + the_chain = &_POSIX_signals_Wait_queue.Queues.Priority[ index ]; + + for ( the_node = the_chain->first ; + !_Chain_Is_tail( the_chain, the_node ) ; + the_node = the_node->next ) { + + the_thread = (Thread_Control *)the_node; + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + + if ((the_thread->Wait.option & mask) || (~api->signals_blocked & mask)) { + goto process_it; + } + + } + } + + /* + * Is any other thread interested? The highest priority interested + * thread is selected. In the event of a tie, then the following + * additional criteria is used: + * + * + ready thread over blocked + * + blocked on call interruptible by signal (can return EINTR) + * + blocked on call not interruptible by signal + * + * This looks at every thread in the system regardless of the creating API. + * + * NOTES: + * + * + rtems internal threads do not receive signals. + */ + + interested_thread = NULL; + interested_priority = PRIORITY_MAXIMUM + 1; + + for ( the_class = OBJECTS_CLASSES_FIRST_THREAD_CLASS; + the_class <= OBJECTS_CLASSES_LAST_THREAD_CLASS; + the_class++ ) { + + if ( the_class == OBJECTS_INTERNAL_THREADS ) + continue; + + the_info = _Objects_Information_table[ the_class ]; + + if ( !the_info ) /* manager not installed */ + continue; + + maximum = the_info->maximum; + object_table = the_info->local_table; + + assert( object_table ); /* always at least 1 entry */ + + for ( index = 1 ; index <= maximum ; index++ ) { + the_thread = (Thread_Control *) object_table[ index ]; + + if ( !the_thread ) + continue; + + /* + * If this thread is of lower priority than the interested thread, + * go on to the next thread. + */ + + if ( the_thread->current_priority > interested_priority ) + continue; + + /* + * If this thread is not interested, then go on to the next thread. + */ + + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + + if ( !api || !_POSIX_signals_Is_interested( api, mask ) ) + continue; + + /* + * Now we know the thread under connsideration is interested. + * If the thread under consideration is of higher priority, then + * it becomes the interested thread. + */ + + if ( the_thread->current_priority < interested_priority ) { + interested_thread = the_thread; + interested_priority = the_thread->current_priority; + continue; + } + + /* + * Now the thread and the interested thread have the same priority. + * If the interested thread is ready, then we don't need to send it + * to a blocked thread. + */ + + if ( _States_Is_ready( interested_thread->current_state ) ) + continue; + + /* + * Now the interested thread is blocked. + * If the thread we are considering is not, the it becomes the + * interested thread. + */ + + if ( _States_Is_ready( the_thread->current_state ) ) { + interested_thread = the_thread; + interested_priority = the_thread->current_priority; + continue; + } + + /* + * Now we know both threads are blocked. + * If the interested thread is interruptible, then just use it. + */ + + /* XXX need a new states macro */ + if ( interested_thread->current_state & STATES_INTERRUPTIBLE_BY_SIGNAL ) + continue; + + /* + * Now both threads are blocked and the interested thread is not + * interruptible. + * If the thread under consideration is interruptible by a signal, + * then it becomes the interested thread. + */ + + /* XXX need a new states macro */ + if ( the_thread->current_state & STATES_INTERRUPTIBLE_BY_SIGNAL ) { + interested_thread = the_thread; + interested_priority = the_thread->current_priority; + } + } + } + + if ( interested_thread ) { + the_thread = interested_thread; + goto process_it; + } + + /* + * OK so no threads were interested right now. It will be left on the + * global pending until a thread receives it. The global set of threads + * can change interest in this signal in one of the following ways: + * + * + a thread is created with the signal unblocked, + * + pthread_sigmask() unblocks the signal, + * + sigprocmask() unblocks the signal, OR + * + sigaction() which changes the handler to SIG_IGN. + */ + + the_thread = NULL; + goto post_process_signal; + + /* + * We found a thread which was interested, so now we mark that this + * thread needs to do the post context switch extension so it can + * evaluate the signals pending. + */ + +process_it: + + the_thread->do_post_task_switch_extension = TRUE; + + /* + * Returns TRUE if the signal was synchronously given to a thread + * blocked waiting for the signal. + */ + + if ( _POSIX_signals_Unblock_thread( the_thread, sig, siginfo ) ) { + _Thread_Enable_dispatch(); + return 0; + } + +post_process_signal: + + /* + * We may have woken up a thread but we definitely need to post the + * signal to the process wide information set. + */ + + _POSIX_signals_Set_process_signals( mask ); + + if ( _POSIX_signals_Vectors[ sig ].sa_flags == SA_SIGINFO ) { + + psiginfo = (POSIX_signals_Siginfo_node *) + _Chain_Get( &_POSIX_signals_Inactive_siginfo ); + if ( !psiginfo ) + set_errno_and_return_minus_one( EAGAIN ); + + psiginfo->Info = *siginfo; + + _Chain_Append( &_POSIX_signals_Siginfo[ sig ], &psiginfo->Node ); + } + + _Thread_Enable_dispatch(); + return 0; +} + +/*PAGE + * + * 3.3.2 Send a Signal to a Process, P1003.1b-1993, p. 68 + * + * NOTE: Behavior of kill() depends on _POSIX_SAVED_IDS. + */ + +int kill( + pid_t pid, + int sig +) +{ + return killinfo( pid, sig, NULL ); +} + +/* + * 3.3.9 Queue a Signal to a Process, P1003.1b-1993, p. 78 + */ + +int sigqueue( + pid_t pid, + int signo, + const union sigval value +) +{ + return killinfo( pid, signo, &value ); +} + +/* + * 3.3.10 Send a Signal to a Thread, P1003.1c/D10, p. 43 + */ + +int pthread_kill( + pthread_t thread, + int sig +) +{ + POSIX_API_Control *api; + Thread_Control *the_thread; + Objects_Locations location; + + if ( sig && !is_valid_signo(sig) ) + set_errno_and_return_minus_one( EINVAL ); + + if ( _POSIX_signals_Vectors[ sig ].sa_flags == SA_SIGINFO ) + set_errno_and_return_minus_one( ENOSYS ); + + /* + * RTEMS does not support sending a siginfo signal to a specific thread. + */ + + the_thread = _POSIX_Threads_Get( thread, &location ); + switch ( location ) { + case OBJECTS_ERROR: + case OBJECTS_REMOTE: + set_errno_and_return_minus_one( ESRCH ); + case OBJECTS_LOCAL: + /* + * If sig == 0 then just validate arguments + */ + + api = the_thread->API_Extensions[ THREAD_API_POSIX ]; + + if ( sig ) { + + if ( _POSIX_signals_Vectors[ sig ].sa_handler == SIG_IGN ) { + _Thread_Enable_dispatch(); + return 0; + } + + /* XXX critical section */ + + api->signals_pending |= signo_to_mask( sig ); + + (void) _POSIX_signals_Unblock_thread( the_thread, sig, NULL ); + + the_thread->do_post_task_switch_extension = TRUE; + + if ( _ISR_Is_in_progress() && _Thread_Is_executing( the_thread ) ) + _ISR_Signals_to_thread_executing = TRUE; + } + _Thread_Enable_dispatch(); + return 0; + } + + return POSIX_BOTTOM_REACHED(); +} + +/* + * 3.4.1 Schedule Alarm, P1003.1b-1993, p. 79 + */ + +Watchdog_Control _POSIX_signals_Alarm_timer; + +unsigned int alarm( + unsigned int seconds +) +{ + unsigned int remaining = 0; + Watchdog_Control *the_timer; + + the_timer = &_POSIX_signals_Alarm_timer; + + switch ( _Watchdog_Remove( the_timer ) ) { + case WATCHDOG_INACTIVE: + case WATCHDOG_BEING_INSERTED: + break; + + case WATCHDOG_ACTIVE: + case WATCHDOG_REMOVE_IT: + remaining = the_timer->initial - + (the_timer->stop_time - the_timer->start_time); + break; + } + + _Watchdog_Insert_seconds( the_timer, seconds ); + + return remaining; +} + +/* + * 3.4.2 Suspend Process Execution, P1003.1b-1993, p. 81 + */ + +int pause( void ) +{ + sigset_t all_signals; + int status; + + (void) sigfillset( &all_signals ); + + status = sigtimedwait( &all_signals, NULL, NULL ); + + return status; +} |