signals.cdl

eCos1.31版

# ====================================================================
#
#      signals.cdl
#
#      C library signal related configuration data
#
# ====================================================================
#####COPYRIGHTBEGIN####
#                                                                          
# -------------------------------------------                              
# The contents of this file are subject to the Red Hat eCos Public License 
# Version 1.1 (the "License"); you may not use this file except in         
# compliance with the License.  You may obtain a copy of the License at    
# http://www.redhat.com/                                                   
#                                                                          
# Software distributed under the License is distributed on an "AS IS"      
# basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the 
# License for the specific language governing rights and limitations under 
# the License.                                                             
#                                                                          
# The Original Code is eCos - Embedded Configurable Operating System,      
# released September 30, 1998.                                             
#                                                                          
# The Initial Developer of the Original Code is Red Hat.                   
# Portions created by Red Hat are                                          
# Copyright (C) 1998, 1999, 2000 Red Hat, Inc.                             
# All Rights Reserved.                                                     
# -------------------------------------------                              
#                                                                          
#####COPYRIGHTEND####
# ====================================================================
######DESCRIPTIONBEGIN####
#
# Author(s):      jskov
# Original data:  jlarmour
# Contributors:
# Date:           1999-07-06
#
#####DESCRIPTIONEND####
#
# ====================================================================


cdl_option CYGSEM_LIBC_SIGNALS_THREAD_SAFE {
    display       "Thread safe signals"
    requires      CYGPKG_KERNEL
    default_value 1
    description   "
        Because signal handlers are global, and not
        thread-specific (as mandated by POSIX 1003.1)
        it is possible for multiple threads to clash
        and corrupt data if setting the same signal
        handler at the same time. With this option
        enabled, a kernel mutex will be used to protect
        the shared data."
}

cdl_component CYGSEM_LIBC_SIGNALS_HWEXCEPTIONS {
    display       "Hardware exceptions cause signals"
    flavor        bool
    requires      CYGSEM_KERNEL_EXCEPTIONS_GLOBAL
    requires      CYGSEM_KERNEL_EXCEPTIONS_DECODE
    default_value 0
    description   "
        This causes hardware exceptions like
        arithmetic exceptions (e.g. divide by zero)
        or bad memory accesses to be passed through as
        signals. It is thus possible for a program to
        handle these exceptions in a generic way using
        the appropriate signal handlers. The details of
        exactly which exceptions are passed through
        under what circumstances depend on the
        underlying HAL implementation. Consequently it
        must be remembered that signal handlers cannot
        be guaranteed to be invoked in the expected
        circumstances if you do not know about the
        underlying HAL implementation - it is possible
        that the architecture is unable to detect that
        exception."

    cdl_option CYGSEM_LIBC_SIGNALS_CHAIN_HWEXCEPTIONS {
        display       "Chain old exception handlers"
        requires      !CYGPKG_HAL_I386_LINUX
        default_value 1
        description   "
            When hardware exceptions are generated, it
            is possible to chain into the old kernel exception
            handler before calling any registered signal
            handler. If this is not required, disable this
            option and only the signal handler will be
            called when this exception occurs. Disabling
            this option will also save some space and code
            usage."
    }
}

cdl_component CYGPKG_LIBC_SIGNALS_INLINE {
    display       "Inline versions of functions"
    flavor        none
    description   "
        Some functions can be made inline instead of
        being function calls. These can be set here."

    cdl_option CYGIMP_LIBC_SIGNALS_RAISE_INLINE {
        display       "raise()"
        default_value 1
        description   "
            Enabling this option makes raise() an inline function."
    }

    cdl_option CYGIMP_LIBC_SIGNALS_SIGNAL_INLINE {
        display       "signal()"
        default_value 1
        description   "
            Enabling this option makes signal() an inline function."
    }
}

cdl_component CYGPKG_LIBC_SIGNALS_ERROR_HANDLING {
    display       "Error handling"
    flavor        none 
    description   "
        You may or may not want errno to be set by
        certain functions. Not using errno could save
        both space, code, and avoid worrying about
        interactions between multiple threads when
        setting it."

    cdl_option CYGSEM_LIBC_SIGNALS_BAD_SIGNAL_FATAL {
        display       "Bad signal fatal"
        requires      CYGDBG_USE_ASSERTS
        default_value 0
        description   "
            Enabling this option will cause an assertion
            failure if the signal handling code is
            passed a bad signal. Otherwise an error will
            be returned, or in the case of a
            hardware-generated exception it will be silently
            ignored."
    }

    cdl_option CYGSEM_LIBC_SIGNALS_RAISE_SETS_ERRNO {
        display       "raise() sets errno"
        default_value 1
        description   "
            You may or may not want errno to be set by
            raise() on error conditions. Not using errno
            could save both space, code, and avoid worrying
            about interactions between multiple threads when
            setting it. Strictly ISO C does not mandate
            that errno be set by raise()."
    }

    cdl_option CYGSEM_LIBC_SIGNALS_SIGNAL_SETS_ERRNO {
        display       "signal() sets errno"
        default_value 1
        description   "
            You may or may not want errno to be set by
            signal() on error conditions. Not using errno
            could save both space, code, and avoid worrying
            about interactions between multiple threads when
            setting it. Strictly ISO C mandates
            that errno be set by signal()."
    }
}

cdl_component CYGPKG_LIBC_SIGNALS_TRACING {
    display       "Tracing"
    flavor        none
    description   "
        These options control the trace output for the C
        library internal signal implementation."

    cdl_option CYGNUM_LIBC_SIGNALS_RAISE_TRACE_LEVEL {
        display       "Default trace level for raise()"
        flavor        data
        legal_values  0 to 1
        default_value 0
        description   "
            This gives the default tracing level for the
            raise() function. Higher numbers are more
            verbose."
    }

    cdl_option CYGNUM_LIBC_SIGNALS_HWHANDLER_TRACE_LEVEL {
        display       "Default hardware exception handler trace level"
        flavor        data
        legal_values  0 to 1
        default_value 0
        description   "
            This gives the default tracing level for the
            hardware exception handler function (if enabled).
            Higher numbers are more verbose."
    }
}