1 # perror.m4 serial 6 2 dnl Copyright (C) 2008-2012 Free Software Foundation, Inc. 3 dnl This file is free software; the Free Software Foundation 4 dnl gives unlimited permission to copy and/or distribute it, 5 dnl with or without modifications, as long as this notice is preserved. 6 7 AC_DEFUN([gl_FUNC_PERROR], 8 [ 9 AC_REQUIRE([gl_STDIO_H_DEFAULTS]) 10 AC_REQUIRE([gl_HEADER_ERRNO_H]) 11 AC_REQUIRE([gl_FUNC_STRERROR_R]) 12 AC_REQUIRE([gl_FUNC_STRERROR_0]) 13 dnl We intentionally do not check for the broader REPLACE_STRERROR_R, 14 dnl since on glibc systems, strerror_r is replaced only for signature 15 dnl issues, and perror is just fine. Rather, we only want to 16 dnl replace perror if strerror_r was replaced for a content fix. 17 if test "$ERRNO_H:$REPLACE_STRERROR_0" != :0; then 18 dnl The system's perror() cannot know about the new errno values we add 19 dnl to <errno.h>, or any fix for strerror(0). Replace it. 20 REPLACE_PERROR=1 21 fi 22 case ${gl_cv_func_strerror_r_works-unset} in 23 unset|*yes) 24 AC_CACHE_CHECK([whether perror matches strerror], 25 [gl_cv_func_perror_works], 26 [AC_RUN_IFELSE( 27 [AC_LANG_PROGRAM( 28 [[#include <errno.h> 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 ]], 33 [[char *str = strerror (-1); 34 if (!getenv("CONFTEST_OUTPUT")) return 0; 35 if (!str) str = ""; 36 puts (str); 37 errno = -1; 38 perror (""); 39 return 0; 40 ]])], 41 [if CONFTEST_OUTPUT=1 ./conftest$EXEEXT >conftest.txt1 2>conftest.txt2 \ 42 && cmp conftest.txt1 conftest.txt2 >/dev/null; then 43 gl_cv_func_perror_works=yes 44 else 45 gl_cv_func_perror_works=no 46 fi 47 rm -rf conftest.txt1 conftest.txt2], 48 [gl_cv_func_perror_works=no], 49 [dnl Guess no when cross-compiling. 50 gl_cv_func_perror_works="guessing no" 51 ]) 52 ]) 53 if test "$gl_cv_func_perror_works" != yes; then 54 REPLACE_PERROR=1 55 fi 56 ;; 57 *) 58 dnl The system's perror() probably inherits the bugs in the 59 dnl system's strerror_r(). Replace it. 60 REPLACE_PERROR=1 61 ;; 62 esac 63 ]) 64
