diff options
Diffstat (limited to 'm4/getcwd.m4')
| -rw-r--r-- | m4/getcwd.m4 | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/m4/getcwd.m4 b/m4/getcwd.m4 new file mode 100644 index 0000000..ba68c5f --- /dev/null +++ b/m4/getcwd.m4 @@ -0,0 +1,164 @@ +# getcwd.m4 - check for working getcwd that is compatible with glibc + +# Copyright (C) 2001, 2003-2007, 2009-2020 Free Software Foundation, Inc. +# This file is free software; the Free Software Foundation +# gives unlimited permission to copy and/or distribute it, +# with or without modifications, as long as this notice is preserved. + +# Written by Paul Eggert. +# serial 18 + +AC_DEFUN([gl_FUNC_GETCWD_NULL], + [ + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CHECK_HEADERS_ONCE([unistd.h]) + AC_CACHE_CHECK([whether getcwd (NULL, 0) allocates memory for result], + [gl_cv_func_getcwd_null], + [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ +# include <stdlib.h> +# if HAVE_UNISTD_H +# include <unistd.h> +# else /* on Windows with MSVC */ +# include <direct.h> +# endif +# ifndef getcwd + char *getcwd (); +# endif +]], [[ +#if defined _WIN32 && ! defined __CYGWIN__ +/* mingw cwd does not start with '/', but getcwd does allocate. + However, mingw fails to honor non-zero size. */ +#else + if (chdir ("/") != 0) + return 1; + else + { + char *f = getcwd (NULL, 0); + if (! f) + return 2; + if (f[0] != '/') + { free (f); return 3; } + if (f[1] != '\0') + { free (f); return 4; } + free (f); + return 0; + } +#endif + ]])], + [gl_cv_func_getcwd_null=yes], + [gl_cv_func_getcwd_null=no], + [[case "$host_os" in + # Guess yes on glibc systems. + *-gnu* | gnu*) gl_cv_func_getcwd_null="guessing yes";; + # Guess yes on musl systems. + *-musl*) gl_cv_func_getcwd_null="guessing yes";; + # Guess yes on Cygwin. + cygwin*) gl_cv_func_getcwd_null="guessing yes";; + # If we don't know, obey --enable-cross-guesses. + *) gl_cv_func_getcwd_null="$gl_cross_guess_normal";; + esac + ]])]) +]) + +AC_DEFUN([gl_FUNC_GETCWD_SIGNATURE], +[ + AC_CACHE_CHECK([for getcwd with POSIX signature], + [gl_cv_func_getcwd_posix_signature], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM( + [[#include <unistd.h>]], + [[extern + #ifdef __cplusplus + "C" + #endif + char *getcwd (char *, size_t); + ]]) + ], + [gl_cv_func_getcwd_posix_signature=yes], + [gl_cv_func_getcwd_posix_signature=no]) + ]) +]) + +dnl Guarantee that getcwd will malloc with a NULL first argument. Assumes +dnl that either the system getcwd is robust, or that calling code is okay +dnl with spurious failures when run from a directory with an absolute name +dnl larger than 4k bytes. +dnl +dnl Assumes that getcwd exists; if you are worried about obsolete +dnl platforms that lacked getcwd(), then you need to use the GPL module. +AC_DEFUN([gl_FUNC_GETCWD_LGPL], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + AC_REQUIRE([gl_FUNC_GETCWD_NULL]) + AC_REQUIRE([gl_FUNC_GETCWD_SIGNATURE]) + + case $gl_cv_func_getcwd_null,$gl_cv_func_getcwd_posix_signature in + *yes,yes) ;; + *) + dnl Minimal replacement lib/getcwd-lgpl.c. + REPLACE_GETCWD=1 + ;; + esac +]) + +dnl Check for all known getcwd bugs; useful for a program likely to be +dnl executed from an arbitrary location. +AC_DEFUN([gl_FUNC_GETCWD], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + AC_REQUIRE([gl_FUNC_GETCWD_NULL]) + AC_REQUIRE([gl_FUNC_GETCWD_SIGNATURE]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + + gl_abort_bug=no + case "$host_os" in + mingw*) + gl_cv_func_getcwd_path_max=yes + ;; + *) + gl_FUNC_GETCWD_PATH_MAX + case "$gl_cv_func_getcwd_null" in + *yes) + gl_FUNC_GETCWD_ABORT_BUG([gl_abort_bug=yes]) + ;; + esac + ;; + esac + dnl Define HAVE_MINIMALLY_WORKING_GETCWD and HAVE_PARTLY_WORKING_GETCWD + dnl if appropriate. + case "$gl_cv_func_getcwd_path_max" in + *"no" | *"no, it has the AIX bug") ;; + *) + AC_DEFINE([HAVE_MINIMALLY_WORKING_GETCWD], [1], + [Define to 1 if getcwd minimally works, that is, its result can be + trusted when it succeeds.]) + ;; + esac + case "$gl_cv_func_getcwd_path_max" in + *"no, but it is partly working") + AC_DEFINE([HAVE_PARTLY_WORKING_GETCWD], [1], + [Define to 1 if getcwd works, except it sometimes fails when it + shouldn't, setting errno to ERANGE, ENAMETOOLONG, or ENOENT.]) + ;; + *"yes, but with shorter paths") + AC_DEFINE([HAVE_GETCWD_SHORTER], [1], + [Define to 1 if getcwd works, but with shorter paths + than is generally tested with the replacement.]) + ;; + esac + + if { case "$gl_cv_func_getcwd_null" in *yes) false;; *) true;; esac; } \ + || test $gl_cv_func_getcwd_posix_signature != yes \ + || { case "$gl_cv_func_getcwd_path_max" in *yes*) false;; *) true;; esac; } \ + || test $gl_abort_bug = yes; then + REPLACE_GETCWD=1 + fi +]) + +# Prerequisites of lib/getcwd.c, when full replacement is in effect. +AC_DEFUN([gl_PREREQ_GETCWD], +[ + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_REQUIRE([gl_CHECK_TYPE_STRUCT_DIRENT_D_INO]) + : +]) |