| # strerror.m4 serial 21 |
| dnl Copyright (C) 2002, 2007-2021 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], |
| [ |
| AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS]) |
| AC_REQUIRE([gl_HEADER_ERRNO_H]) |
| AC_REQUIRE([gl_FUNC_STRERROR_0]) |
| AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles |
| m4_ifdef([gl_FUNC_STRERROR_R_WORKS], [ |
| AC_REQUIRE([gl_FUNC_STRERROR_R_WORKS]) |
| ]) |
| if test "$ERRNO_H:$REPLACE_STRERROR_0" = :0; then |
| AC_CACHE_CHECK([for working strerror function], |
| [gl_cv_func_working_strerror], |
| [AC_RUN_IFELSE( |
| [AC_LANG_PROGRAM( |
| [[#include <string.h> |
| ]], |
| [[if (!*strerror (-2)) return 1;]])], |
| [gl_cv_func_working_strerror=yes], |
| [gl_cv_func_working_strerror=no], |
| [case "$host_os" in |
| # Guess yes on glibc systems. |
| *-gnu* | gnu*) gl_cv_func_working_strerror="guessing yes" ;; |
| # Guess yes on musl systems. |
| *-musl*) gl_cv_func_working_strerror="guessing yes" ;; |
| # If we don't know, obey --enable-cross-guesses. |
| *) gl_cv_func_working_strerror="$gl_cross_guess_normal" ;; |
| esac |
| ]) |
| ]) |
| case "$gl_cv_func_working_strerror" in |
| *yes) ;; |
| *) |
| dnl The system's strerror() fails to return a string for out-of-range |
| dnl integers. Replace it. |
| REPLACE_STRERROR=1 |
| ;; |
| esac |
| m4_ifdef([gl_FUNC_STRERROR_R_WORKS], [ |
| dnl If the system's strerror_r or __xpg_strerror_r clobbers strerror's |
| dnl buffer, we must replace strerror. |
| case "$gl_cv_func_strerror_r_works" in |
| *no) REPLACE_STRERROR=1 ;; |
| esac |
| ]) |
| else |
| dnl The system's strerror() cannot know about the new errno values we add |
| dnl to <errno.h>, or any fix for strerror(0). Replace it. |
| REPLACE_STRERROR=1 |
| fi |
| ]) |
| |
| dnl Detect if strerror(0) passes (that is, does not set errno, and does not |
| dnl return a string that matches strerror(-1)). |
| AC_DEFUN([gl_FUNC_STRERROR_0], |
| [ |
| AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles |
| REPLACE_STRERROR_0=0 |
| AC_CACHE_CHECK([whether strerror(0) succeeds], |
| [gl_cv_func_strerror_0_works], |
| [AC_RUN_IFELSE( |
| [AC_LANG_PROGRAM( |
| [[#include <string.h> |
| #include <errno.h> |
| ]], |
| [[int result = 0; |
| char *str; |
| errno = 0; |
| str = strerror (0); |
| if (!*str) result |= 1; |
| if (errno) result |= 2; |
| if (strstr (str, "nknown") || strstr (str, "ndefined")) |
| result |= 4; |
| return result;]])], |
| [gl_cv_func_strerror_0_works=yes], |
| [gl_cv_func_strerror_0_works=no], |
| [case "$host_os" in |
| # Guess yes on glibc systems. |
| *-gnu* | gnu*) gl_cv_func_strerror_0_works="guessing yes" ;; |
| # Guess yes on musl systems. |
| *-musl*) gl_cv_func_strerror_0_works="guessing yes" ;; |
| # Guess yes on native Windows. |
| mingw*) gl_cv_func_strerror_0_works="guessing yes" ;; |
| # If we don't know, obey --enable-cross-guesses. |
| *) gl_cv_func_strerror_0_works="$gl_cross_guess_normal" ;; |
| esac |
| ]) |
| ]) |
| case "$gl_cv_func_strerror_0_works" in |
| *yes) ;; |
| *) |
| REPLACE_STRERROR_0=1 |
| AC_DEFINE([REPLACE_STRERROR_0], [1], [Define to 1 if strerror(0) |
| does not return a message implying success.]) |
| ;; |
| esac |
| ]) |