1: /* Code to enable profiling at program startup.
    2:    Copyright (C) 1995,1996,1997,2000,2001,2002 Free Software Foundation, Inc.
    3:    This file is part of the GNU C Library.
    4: 
    5:    The GNU C Library is free software; you can redistribute it and/or
    6:    modify it under the terms of the GNU Lesser General Public
    7:    License as published by the Free Software Foundation; either
    8:    version 2.1 of the License, or (at your option) any later version.
    9: 
   10:    The GNU C Library is distributed in the hope that it will be useful,
   11:    but WITHOUT ANY WARRANTY; without even the implied warranty of
   12:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   13:    Lesser General Public License for more details.
   14: 
   15:    You should have received a copy of the GNU Lesser General Public
   16:    License along with the GNU C Library; if not, write to the Free
   17:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   18:    02111-1307 USA.  */
   19: 
   20: #include <sys/types.h>
   21: #include <sys/gmon.h>
   22: #include <stdlib.h>
   23: #include <unistd.h>
   24: #define __ASSEMBLY__
   25: #include <entry.h>
   26: 
   27: /* Beginning and end of our code segment. We cannot declare them
   28:    as the external functions since we want the addresses of those
   29:    labels. Taking the address of a function may have different
   30:    meanings on different platforms. */
   31: #ifdef ENTRY_POINT_DECL
   32: ENTRY_POINT_DECL(extern)
   33: #else
   34: extern void ENTRY_POINT;
   35: #endif
   36: extern void etext;
   37: 
   38: #ifndef TEXT_START
   39: # ifdef ENTRY_POINT_DECL
   40: #  define TEXT_START ENTRY_POINT
   41: # else
   42: #  define TEXT_START &ENTRY_POINT
   43: # endif
   44: #endif
   45: 
   46: #ifndef HAVE_INITFINI
   47: /* This function gets called at startup by the normal constructor
   48:    mechanism.  We link this file together with start.o to produce gcrt1.o,
   49:    so this constructor will be first in the list.  */
   50: 
   51: extern void __gmon_start__ (void) __attribute__ ((constructor));
   52: #else
   53: /* In ELF and COFF, we cannot use the normal constructor mechanism to call
   54:    __gmon_start__ because gcrt1.o appears before crtbegin.o in the link.
   55:    Instead crti.o calls it specially (see initfini.c).  */
   56: extern void __gmon_start__ (void);
   57: #endif
   58: 
   59: void
   60: __gmon_start__ (void)
   61: {
   62: #ifdef HAVE_INITFINI
   63:   /* Protect from being called more than once.  Since crti.o is linked
   64:      into every shared library, each of their init functions will call us.  */
   65:   static int called;
   66: 
   67:   if (called)
   68:     return;
   69: 
   70:   called = 1;
   71: #endif
   72: 
   73:   /* Start keeping profiling records.  */
   74:   __monstartup ((u_long) TEXT_START, (u_long) &etext);
   75: 
   76:   /* Call _mcleanup before exiting; it will write out gmon.out from the
   77:      collected data.  */
   78:   atexit (&_mcleanup);
   79: }