signal.inl

ecos实时嵌入式操作系统

#ifndef CYGONCE_LIBC_SIGNALS_SIGNAL_INL
#define CYGONCE_LIBC_SIGNALS_SIGNAL_INL
//========================================================================
//
//      signal.inl
//
//      Inline functions for implementation of ISO C and POSIX signals
//
//========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos 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 or (at your option) any later version.
//
// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):     jlarmour
// Contributors:  
// Date:          2000-04-18
// Purpose:       Implements required inline functions of ISO C and
//                POSIX 1003.1 signals
// Description:   
// Usage:         Do not include this file directly, instead use <signal.h>
//
//####DESCRIPTIONEND####
//
//========================================================================

// CONFIGURATION

#include <pkgconf/libc_signals.h>  // libc signals configuration

// INCLUDES

#include <signal.h>                // Header for this file, just in case
#include <cyg/infra/cyg_ass.h>     // Assertion infrastructure
#include <cyg/infra/cyg_trac.h>    // Tracing infrastructure

// GLOBALS

extern __sighandler_t cyg_libc_signal_handlers[];
#ifdef CYGDBG_USE_TRACING
extern cyg_uint8 cyg_libc_signals_raise_trace_level;
#endif

// DEFINES

// The following are overriden by the libc implementation to get a non-inline
// version to prevent duplication of code
#ifndef CYGPRI_LIBC_SIGNALS_RAISE_INLINE
# define CYGPRI_LIBC_SIGNALS_RAISE_INLINE extern __inline__
#endif

#ifndef CYGPRI_LIBC_SIGNALS_SIGNAL_INLINE
# define CYGPRI_LIBC_SIGNALS_SIGNAL_INLINE extern __inline__
#endif

// FUNCTION PROTOTYPES

#ifdef __cplusplus
extern "C" {
#endif

// Default signal handler - SIG_DFL
extern void cyg_libc_signals_default_handler(int __sig);

#ifdef CYGSEM_LIBC_SIGNALS_THREAD_SAFE
extern cyg_bool cyg_libc_signals_lock_do_lock(void);
extern void cyg_libc_signals_lock_do_unlock(void);
#endif

// INLINE FUNCTIONS

/////////////////////////////
// cyg_libc_signals_lock() //
/////////////////////////////

static inline cyg_bool
cyg_libc_signals_lock(void)
{
#ifdef CYGSEM_LIBC_SIGNALS_THREAD_SAFE
    return cyg_libc_signals_lock_do_lock();
#else
    return true;
#endif
} // cyg_libc_signals_lock()

///////////////////////////////
// cyg_libc_signals_unlock() //
///////////////////////////////

static inline void
cyg_libc_signals_unlock(void)
{
#ifdef CYGSEM_LIBC_SIGNALS_THREAD_SAFE
    cyg_libc_signals_lock_do_unlock();
#else
    return;
#endif
} // cyg_libc_signals_unlock()

// ISO C functions

//////////////////////////////
// signal() - ISO C 7.7.1   //
//////////////////////////////


#ifdef CYGIMP_LIBC_SIGNALS_SIGNAL_INLINE

#ifdef CYGSEM_LIBC_SIGNALS_SIGNAL_SETS_ERRNO
# include <errno.h>                 // errno
#endif

CYGPRI_LIBC_SIGNALS_SIGNAL_INLINE __sighandler_t
signal(int __sig, __sighandler_t __handler)
{
    __sighandler_t __old_handler;
    CYG_REPORT_FUNCNAMETYPE( "__signal", "returning %08x" );
    
    CYG_REPORT_FUNCARG2( "signal number = %d, requested handler is at %08x",
                         __sig, __handler );

    // check valid signal - raise should not raise the null signal either
    if ( (__sig >= CYGNUM_LIBC_SIGNALS) || (__sig <= 0) ) {

#ifdef CYGSEM_LIBC_SIGNALS_BAD_SIGNAL_FATAL
        CYG_FAIL("__signal() passed bad signal number");
#else
# ifdef CYGSEM_LIBC_SIGNALS_SIGNAL_SETS_ERRNO
        errno = EINVAL;
# endif
        return SIG_ERR;
#endif
    }

    // paranoia
    CYG_CHECK_DATA_PTR( cyg_libc_signal_handlers,
                        "signal handler array is invalid!" );
    if ( (__handler != SIG_IGN) && (__handler != SIG_DFL) )
        CYG_CHECK_FUNC_PTR( __handler, "__signal() passed invalid handler");
    
    if (!cyg_libc_signals_lock()) {
#ifdef CYGSEM_LIBC_SIGNALS_SIGNAL_SETS_ERRNO
        errno = EINTR;
#endif
        return SIG_ERR;
    } // if

    __old_handler = cyg_libc_signal_handlers[__sig];
    cyg_libc_signal_handlers[__sig] = __handler;
    
    cyg_libc_signals_unlock();

    CYG_REPORT_RETVAL( __old_handler );
   
    return __old_handler;
} // signal()
#endif // ifdef CYGIMP_LIBC_SIGNALS_SIGNAL_INLINE


///////////////////////////
// raise() - ISO C 7.7.2 //
///////////////////////////

#ifdef CYGIMP_LIBC_SIGNALS_RAISE_INLINE

#ifdef CYGSEM_LIBC_SIGNALS_RAISE_SETS_ERRNO
# include <errno.h>                 // errno
#endif

CYGPRI_LIBC_SIGNALS_RAISE_INLINE int
raise(int __sig)
{
    int __ret=0;
    __sighandler_t __sigfun;
    
    CYG_REPORT_FUNCNAMETYPE( "__raise", "returning %d" );
    
    CYG_REPORT_FUNCARG1( "signal number = %d", __sig );

    // check valid signal - raise should not raise the null signal either
    if ( (__sig >= CYGNUM_LIBC_SIGNALS) || (__sig <= 0) ) {

#ifdef CYGSEM_LIBC_SIGNALS_BAD_SIGNAL_FATAL
        CYG_FAIL("__raise() passed bad signal number");
#else
# ifdef CYGSEM_LIBC_SIGNALS_RAISE_SETS_ERRNO
        errno = EINVAL;
# endif
        return -1;
#endif
    }

    // paranoia
    CYG_CHECK_DATA_PTR( cyg_libc_signal_handlers,
                        "signal handler array is invalid!" );
    
    if (!cyg_libc_signals_lock()) {
#ifdef CYGSEM_LIBC_SIGNALS_RAISE_SETS_ERRNO
        errno = EINTR;
#endif
        return -1;
    } // if

    __sigfun = cyg_libc_signal_handlers[__sig];

    if ( __sigfun == SIG_DFL ) {
        CYG_TRACE0(cyg_libc_signals_raise_trace_level,
                   "signal handler returned is SIG_DFL");
        cyg_libc_signals_unlock();
        cyg_libc_signals_default_handler(__sig);
    } else if ( __sigfun == SIG_IGN ) {
        CYG_TRACE0(cyg_libc_signals_raise_trace_level,
                   "signal handler returned is SIG_IGN");
        cyg_libc_signals_unlock();
    } else {
        CYG_TRACE1(cyg_libc_signals_raise_trace_level,
                   "signal handler returned is at %08x", __sigfun);
        // call the signal handler directly
        cyg_libc_signal_handlers[__sig] = SIG_DFL;

        cyg_libc_signals_unlock();
        CYG_CHECK_FUNC_PTR( __sigfun, "returned signal handler invalid!");

        (*__sigfun)(__sig);
    }

    CYG_REPORT_RETVAL( __ret );

    return __ret;
} // raise()
#endif // ifdef CYGIMP_LIBC_SIGNALS_RAISE_INLINE


#ifdef __cplusplus
} // extern "C"
#endif 

#endif // CYGONCE_LIBC_SIGNALS_SIGNAL_INL multiple inclusion protection

// EOF signal.inl