From a405fc138596f552581d2011fd6de02d5c8186c4 Mon Sep 17 00:00:00 2001 From: RincewindsHat <12514511+RincewindsHat@users.noreply.github.com> Date: Wed, 17 Nov 2021 01:05:54 +0100 Subject: Sync with the latest Gnulib code (1a268176f) --- gl/m4/lseek.m4 | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 gl/m4/lseek.m4 (limited to 'gl/m4/lseek.m4') diff --git a/gl/m4/lseek.m4 b/gl/m4/lseek.m4 new file mode 100644 index 00000000..faab09b7 --- /dev/null +++ b/gl/m4/lseek.m4 @@ -0,0 +1,78 @@ +# lseek.m4 serial 12 +dnl Copyright (C) 2007, 2009-2021 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_LSEEK], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + + AC_REQUIRE([AC_CANONICAL_HOST]) + AC_REQUIRE([AC_PROG_CC]) + AC_CHECK_HEADERS_ONCE([unistd.h]) + AC_CACHE_CHECK([whether lseek detects pipes], [gl_cv_func_lseek_pipe], + [case "$host_os" in + mingw*) + dnl Native Windows. + dnl The result of lseek (fd, (off_t)0, SEEK_CUR) or + dnl SetFilePointer(handle, 0, NULL, FILE_CURRENT) + dnl for a pipe depends on the environment: In a Cygwin 1.5 + dnl environment it succeeds (wrong); in a Cygwin 1.7 environment + dnl it fails with a wrong errno value. + gl_cv_func_lseek_pipe=no + ;; + *) + if test $cross_compiling = no; then + AC_LINK_IFELSE([AC_LANG_PROGRAM([[ +#include /* for off_t */ +#include /* for SEEK_CUR */ +#if HAVE_UNISTD_H +# include +#else /* on Windows with MSVC */ +# include +#endif +]GL_MDA_DEFINES], +[[ + /* Exit with success only if stdin is seekable. */ + return lseek (0, (off_t)0, SEEK_CUR) < 0; +]])], + [if test -s conftest$ac_exeext \ + && ./conftest$ac_exeext < conftest.$ac_ext \ + && test 1 = "`echo hi \ + | { ./conftest$ac_exeext; echo $?; cat >/dev/null; }`"; then + gl_cv_func_lseek_pipe=yes + else + gl_cv_func_lseek_pipe=no + fi + ], + [gl_cv_func_lseek_pipe=no]) + else + AC_COMPILE_IFELSE( + [AC_LANG_SOURCE([[ +#if defined __BEOS__ +/* BeOS mistakenly return 0 when trying to seek on pipes. */ + Choke me. +#endif]])], + [gl_cv_func_lseek_pipe=yes], [gl_cv_func_lseek_pipe=no]) + fi + ;; + esac + ]) + if test "$gl_cv_func_lseek_pipe" = no; then + REPLACE_LSEEK=1 + AC_DEFINE([LSEEK_PIPE_BROKEN], [1], + [Define to 1 if lseek does not detect pipes.]) + fi + + AC_REQUIRE([gl_SYS_TYPES_H]) + if test $WINDOWS_64_BIT_OFF_T = 1; then + REPLACE_LSEEK=1 + fi + + dnl macOS SEEK_DATA is incompatible with other platforms. + case $host_os in + darwin*) + REPLACE_LSEEK=1;; + esac +]) -- cgit v1.2.3-74-g34f1