# strerror_r.m4 serial 18 dnl Copyright (C) 2002, 2007-2017 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. AC_DEFUN([gl_FUNC_STRERROR_R], [ AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS]) AC_REQUIRE([gl_FUNC_STRERROR_R_WORKS]) dnl Persuade Solaris to declare strerror_r(). AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) dnl Some systems don't declare strerror_r() if _THREAD_SAFE and _REENTRANT dnl are not defined. AC_CHECK_DECL([strerror_r], [HAVE_DECL_STRERROR_R=1], [HAVE_DECL_STRERROR_R=0]) AC_DEFINE_UNQUOTED([HAVE_DECL_STRERROR_R_ORIG], [$HAVE_DECL_STRERROR_R], [Define to 1 if you have the declaration of 'strerror_r' in the system include files, or to 0 otherwise.]) if test $ac_cv_func_strerror_r = yes; then if test "$ERRNO_H:$REPLACE_STRERROR_0" = :0; then if test $gl_cv_func_strerror_r_posix_signature = yes; then case "$gl_cv_func_strerror_r_works" in dnl The system's strerror_r has bugs. Replace it. *no) REPLACE_STRERROR_R=1 ;; esac else dnl The system's strerror_r() has a wrong signature. Replace it. REPLACE_STRERROR_R=1 fi else dnl The system's strerror_r() cannot know about the new errno values we dnl add to , or any fix for strerror(0). Replace it. REPLACE_STRERROR_R=1 fi fi # Overwrite the findings of AC_FUNC_STRERROR_R (for code that uses that). AC_REQUIRE([AC_FUNC_STRERROR_R]) ]) # If this module is in use, we unconditionally want POSIX semantics; so # replace autoconf's macro with a version that does not probe AC_DEFUN([AC_FUNC_STRERROR_R], [ AC_DEFINE([HAVE_DECL_STRERROR_R], [1], [Define to 1, since you should have the declaration of strerror_r.]) AC_DEFINE([HAVE_STRERROR_R], [1], [Define to 1, since you should have the function strerror_r.]) AC_DEFINE([STRERROR_R_CHAR_P], [0], [Define to 0, since strerror_r should not return char *.]) ]) # Prerequisites of lib/strerror_r.c. AC_DEFUN([gl_PREREQ_STRERROR_R], [ dnl glibc >= 2.3.4 and cygwin 1.7.9 have a function __xpg_strerror_r. AC_CHECK_FUNCS_ONCE([__xpg_strerror_r]) AC_CHECK_FUNCS_ONCE([catgets]) AC_CHECK_FUNCS_ONCE([snprintf]) ]) # Detect if strerror_r works, but without affecting whether a replacement # strerror_r will be used. AC_DEFUN([gl_FUNC_STRERROR_R_WORKS], [ AC_REQUIRE([gl_HEADER_ERRNO_H]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles AC_REQUIRE([gl_FUNC_STRERROR_0]) AC_CHECK_FUNC([strerror_r]) if test $ac_cv_func_strerror_r = yes; then if test "$ERRNO_H:$REPLACE_STRERROR_0" = :0; then dnl The POSIX prototype is: int strerror_r (int, char *, size_t); dnl glibc, Cygwin: char *strerror_r (int, char *, size_t); dnl AIX 5.1, OSF/1 5.1: int strerror_r (int, char *, int); AC_CACHE_CHECK([for strerror_r with POSIX signature], [gl_cv_func_strerror_r_posix_signature], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[#include int strerror_r (int, char *, size_t); ]], [])], [gl_cv_func_strerror_r_posix_signature=yes], [gl_cv_func_strerror_r_posix_signature=no]) ]) if test $gl_cv_func_strerror_r_posix_signature = yes; then dnl AIX 6.1 strerror_r fails by returning -1, not an error number. dnl HP-UX 11.31 strerror_r always fails when the buffer length argument dnl is less than 80. dnl FreeBSD 8.s strerror_r claims failure on 0 dnl Mac OS X 10.5 strerror_r treats 0 like -1 dnl Solaris 10 strerror_r corrupts errno on failure AC_CACHE_CHECK([whether strerror_r works], [gl_cv_func_strerror_r_works], [AC_RUN_IFELSE( [AC_LANG_PROGRAM( [[#include #include ]], [[int result = 0; char buf[79]; if (strerror_r (EACCES, buf, 0) < 0) result |= 1; errno = 0; if (strerror_r (EACCES, buf, sizeof buf) != 0) result |= 2; strcpy (buf, "Unknown"); if (strerror_r (0, buf, sizeof buf) != 0) result |= 4; if (errno) result |= 8; if (strstr (buf, "nknown") || strstr (buf, "ndefined")) result |= 0x10; errno = 0; *buf = 0; if (strerror_r (-3, buf, sizeof buf) < 0) result |= 0x20; if (errno) result |= 0x40; if (!*buf) result |= 0x80; return result; ]])], [gl_cv_func_strerror_r_works=yes], [gl_cv_func_strerror_r_works=no], [ changequote(,)dnl case "$host_os" in # Guess no on AIX. aix*) gl_cv_func_strerror_r_works="guessing no";; # Guess no on HP-UX. hpux*) gl_cv_func_strerror_r_works="guessing no";; # Guess no on BSD variants. *bsd*) gl_cv_func_strerror_r_works="guessing no";; # Guess yes otherwise. *) gl_cv_func_strerror_r_works="guessing yes";; esac changequote([,])dnl ]) ]) else dnl The system's strerror() has a wrong signature. dnl glibc >= 2.3.4 and cygwin 1.7.9 have a function __xpg_strerror_r. AC_CHECK_FUNCS_ONCE([__xpg_strerror_r]) dnl In glibc < 2.14, __xpg_strerror_r does not populate buf on failure. dnl In cygwin < 1.7.10, __xpg_strerror_r clobbers strerror's buffer. if test $ac_cv_func___xpg_strerror_r = yes; then AC_CACHE_CHECK([whether __xpg_strerror_r works], [gl_cv_func_strerror_r_works], [AC_RUN_IFELSE( [AC_LANG_PROGRAM( [[#include #include extern #ifdef __cplusplus "C" #endif int __xpg_strerror_r(int, char *, size_t); ]], [[int result = 0; char buf[256] = "^"; char copy[256]; char *str = strerror (-1); strcpy (copy, str); if (__xpg_strerror_r (-2, buf, 1) == 0) result |= 1; if (*buf) result |= 2; __xpg_strerror_r (-2, buf, 256); if (strcmp (str, copy)) result |= 4; return result; ]])], [gl_cv_func_strerror_r_works=yes], [gl_cv_func_strerror_r_works=no], [dnl Guess no on all platforms that have __xpg_strerror_r, dnl at least until fixed glibc and cygwin are more common. gl_cv_func_strerror_r_works="guessing no" ]) ]) fi fi fi fi ])