diff options
Diffstat (limited to 'gnulib/import/m4/threadlib.m4')
| -rw-r--r-- | gnulib/import/m4/threadlib.m4 | 407 |
1 files changed, 277 insertions, 130 deletions
diff --git a/gnulib/import/m4/threadlib.m4 b/gnulib/import/m4/threadlib.m4 index 96c74c1..94441f6 100644 --- a/gnulib/import/m4/threadlib.m4 +++ b/gnulib/import/m4/threadlib.m4 @@ -1,5 +1,5 @@ -# threadlib.m4 serial 24 -dnl Copyright (C) 2005-2019 Free Software Foundation, Inc. +# threadlib.m4 serial 27 +dnl Copyright (C) 2005-2020 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. @@ -8,46 +8,48 @@ dnl From Bruno Haible. AC_PREREQ([2.60]) -dnl gl_PTHREADLIB -dnl ------------- -dnl Tests for the libraries needs for using the POSIX threads API. -dnl Sets the variable LIBPTHREAD to the linker options for use in a Makefile. -dnl Sets the variable LIBPMULTITHREAD, for programs that really need -dnl multithread functionality. The difference between LIBPTHREAD and -dnl LIBPMULTITHREAD is that on platforms supporting weak symbols, typically -dnl LIBPTHREAD is empty whereas LIBPMULTITHREAD is not. -dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for -dnl multithread-safe programs. -dnl Defines the C macro HAVE_PTHREAD_API if (at least parts of) the POSIX -dnl threads API is available. +dnl The general structure of the multithreading modules in gnulib is that we +dnl have three set of modules: +dnl +dnl * POSIX API: +dnl pthread, which combines +dnl pthread-h +dnl pthread-thread +dnl pthread-once +dnl pthread-mutex +dnl pthread-rwlock +dnl pthread-cond +dnl pthread-tss +dnl pthread-spin +dnl sched_yield +dnl +dnl * ISO C API: +dnl threads, which combines +dnl threads-h +dnl thrd +dnl mtx +dnl cnd +dnl tss +dnl +dnl * Gnulib API, with an implementation that can be chosen at configure +dnl time through the option --enable-threads=... +dnl thread +dnl lock +dnl cond +dnl tls +dnl yield +dnl +dnl They are independent, except for the fact that +dnl - the implementation of the ISO C API may use the POSIX (or some other +dnl platform dependent) API, +dnl - the implementation of the Gnulib API may use the POSIX or ISO C or +dnl some other platform dependent API, depending on the --enable-threads +dnl option. +dnl +dnl This file contains macros for all of these APIs! -dnl gl_THREADLIB -dnl ------------ -dnl Tests for a multithreading library to be used. -dnl If the configure.ac contains a definition of the gl_THREADLIB_DEFAULT_NO -dnl (it must be placed before the invocation of gl_THREADLIB_EARLY!), then the -dnl default is 'no', otherwise it is system dependent. In both cases, the user -dnl can change the choice through the options --enable-threads=choice or -dnl --disable-threads. -dnl Defines at most one of the macros USE_ISOC_THREADS, USE_POSIX_THREADS, -dnl USE_ISOC_AND_POSIX_THREADS, USE_WINDOWS_THREADS. -dnl The choice --enable-threads=isoc+posix is available only on platforms that -dnl have both the ISO C and the POSIX threads APIs. It has the effect of using -dnl the ISO C API for most things and the POSIX API only for creating and -dnl controlling threads (because there is no equivalent to pthread_atfork in -dnl the ISO C API). -dnl Sets the variables LIBTHREAD and LTLIBTHREAD to the linker options for use -dnl in a Makefile (LIBTHREAD for use without libtool, LTLIBTHREAD for use with -dnl libtool). -dnl Sets the variables LIBMULTITHREAD and LTLIBMULTITHREAD similarly, for -dnl programs that really need multithread functionality. The difference -dnl between LIBTHREAD and LIBMULTITHREAD is that on platforms supporting weak -dnl symbols, typically LIBTHREAD is empty whereas LIBMULTITHREAD is not. -dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for -dnl multithread-safe programs. -dnl Since support for GNU pth was removed, $LTLIBTHREAD and $LIBTHREAD have the -dnl same value, and similarly $LTLIBMULTITHREAD and $LIBMULTITHREAD have the -dnl same value. Only system libraries are needed. +dnl ============================================================================ +dnl Macros for all thread APIs AC_DEFUN([gl_ANYTHREADLIB_EARLY], [ @@ -75,77 +77,11 @@ AC_DEFUN([gl_ANYTHREADLIB_EARLY], fi ]) -AC_DEFUN([gl_THREADLIB_EARLY], -[ - AC_REQUIRE([gl_THREADLIB_EARLY_BODY]) -]) - -dnl The guts of gl_THREADLIB_EARLY. Needs to be expanded only once. - -AC_DEFUN([gl_THREADLIB_EARLY_BODY], -[ - dnl Ordering constraints: This macro modifies CPPFLAGS in a way that - dnl influences the result of the autoconf tests that test for *_unlocked - dnl declarations, on AIX 5 at least. Therefore it must come early. - AC_BEFORE([$0], [gl_FUNC_GLIBC_UNLOCKED_IO])dnl - AC_BEFORE([$0], [gl_ARGP])dnl - - AC_REQUIRE([AC_CANONICAL_HOST]) - dnl _GNU_SOURCE is needed for pthread_rwlock_t on glibc systems. - AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) - dnl Check for multithreading. - m4_ifdef([gl_THREADLIB_DEFAULT_NO], - [m4_divert_text([DEFAULTS], [gl_use_threads_default=no])], - [m4_divert_text([DEFAULTS], [gl_use_threads_default=])]) - m4_divert_text([DEFAULTS], [gl_use_winpthreads_default=]) - AC_ARG_ENABLE([threads], -AC_HELP_STRING([--enable-threads={isoc|posix|isoc+posix|windows}], [specify multithreading API])m4_ifdef([gl_THREADLIB_DEFAULT_NO], [], [ -AC_HELP_STRING([--disable-threads], [build without multithread safety])]), - [gl_use_threads=$enableval], - [if test -n "$gl_use_threads_default"; then - gl_use_threads="$gl_use_threads_default" - else -changequote(,)dnl - case "$host_os" in - dnl Disable multithreading by default on OSF/1, because it interferes - dnl with fork()/exec(): When msgexec is linked with -lpthread, its - dnl child process gets an endless segmentation fault inside execvp(). - osf*) gl_use_threads=no ;; - dnl Disable multithreading by default on Cygwin 1.5.x, because it has - dnl bugs that lead to endless loops or crashes. See - dnl <https://cygwin.com/ml/cygwin/2009-08/msg00283.html>. - cygwin*) - case `uname -r` in - 1.[0-5].*) gl_use_threads=no ;; - *) gl_use_threads=yes ;; - esac - ;; - dnl Obey gl_AVOID_WINPTHREAD on mingw. - mingw*) - case "$gl_use_winpthreads_default" in - yes) gl_use_threads=posix ;; - no) gl_use_threads=windows ;; - *) gl_use_threads=yes ;; - esac - ;; - *) gl_use_threads=yes ;; - esac -changequote([,])dnl - fi - ]) - if test "$gl_use_threads" = yes \ - || test "$gl_use_threads" = isoc \ - || test "$gl_use_threads" = posix \ - || test "$gl_use_threads" = isoc+posix; then - # For using <threads.h> or <pthread.h>: - gl_ANYTHREADLIB_EARLY - fi -]) - dnl Checks whether the compiler and linker support weak declarations of symbols. AC_DEFUN([gl_WEAK_SYMBOLS], [ + AC_REQUIRE([AC_CANONICAL_HOST]) AC_CACHE_CHECK([whether imported symbols can be declared weak], [gl_cv_have_weak], [gl_cv_have_weak=no @@ -184,6 +120,30 @@ int main () case " $LDFLAGS " in *" -static "*) gl_cv_have_weak=no ;; esac + dnl Test for a bug in FreeBSD 11: A link error occurs when using a weak + dnl symbol and linking against a shared library that has a dependency on + dnl the shared library that defines the symbol. + case "$gl_cv_have_weak" in + *yes) + case "$host_os" in + freebsd* | dragonfly*) + : > conftest1.c + $CC $CPPFLAGS $CFLAGS $LDFLAGS -fPIC -shared -o libempty.so conftest1.c -lpthread >&AS_MESSAGE_LOG_FD 2>&1 + cat <<EOF > conftest2.c +#include <pthread.h> +#pragma weak pthread_mutexattr_gettype +int main () +{ + return (pthread_mutexattr_gettype != NULL); +} +EOF + $CC $CPPFLAGS $CFLAGS $LDFLAGS -o conftest conftest2.c libempty.so >&AS_MESSAGE_LOG_FD 2>&1 \ + || gl_cv_have_weak=no + rm -f conftest1.c libempty.so conftest2.c conftest + ;; + esac + ;; + esac ]) case "$gl_cv_have_weak" in *yes) @@ -193,12 +153,30 @@ int main () esac ]) +dnl ============================================================================ +dnl Macros for the POSIX API + +dnl gl_PTHREADLIB +dnl ------------- +dnl Tests for the libraries needs for using the POSIX threads API. +dnl Sets the variable LIBPTHREAD to the linker options for use in a Makefile. +dnl Sets the variable LIBPMULTITHREAD, for programs that really need +dnl multithread functionality. The difference between LIBPTHREAD and +dnl LIBPMULTITHREAD is that on platforms supporting weak symbols, typically +dnl LIBPTHREAD is empty whereas LIBPMULTITHREAD is not. +dnl Sets the variable LIB_SCHED_YIELD to the linker options needed to use the +dnl sched_yield() function. +dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for +dnl multithread-safe programs. +dnl Defines the C macro HAVE_PTHREAD_API if (at least parts of) the POSIX +dnl threads API is available. + dnl The guts of gl_PTHREADLIB. Needs to be expanded only once. AC_DEFUN([gl_PTHREADLIB_BODY], [ AC_REQUIRE([gl_ANYTHREADLIB_EARLY]) - if test -z "$gl_threadlib_body_done"; then + if test -z "$gl_pthreadlib_body_done"; then gl_pthread_api=no LIBPTHREAD= LIBPMULTITHREAD= @@ -277,7 +255,189 @@ AC_DEFUN([gl_PTHREADLIB_BODY], AC_DEFINE([HAVE_PTHREAD_API], [1], [Define if you have the <pthread.h> header and the POSIX threads API.]) fi - gl_threadlib_body_done=done + + dnl On some systems, sched_yield is in librt, rather than in libpthread. + AC_LINK_IFELSE( + [AC_LANG_PROGRAM( + [[#include <sched.h>]], + [[sched_yield ();]])], + [LIB_SCHED_YIELD= + ], + [dnl Solaris 7...10 has sched_yield in librt, not in libpthread or libc. + AC_CHECK_LIB([rt], [sched_yield], [LIB_SCHED_YIELD=-lrt], + [dnl Solaris 2.5.1, 2.6 has sched_yield in libposix4, not librt. + AC_CHECK_LIB([posix4], [sched_yield], [LIB_SCHED_YIELD=-lposix4])]) + ]) + AC_SUBST([LIB_SCHED_YIELD]) + + gl_pthreadlib_body_done=done + fi +]) + +AC_DEFUN([gl_PTHREADLIB], +[ + AC_REQUIRE([gl_ANYTHREADLIB_EARLY]) + gl_PTHREADLIB_BODY +]) + +dnl ============================================================================ +dnl Macros for the ISO C API + +dnl gl_STDTHREADLIB +dnl --------------- +dnl Tests for the libraries needs for using the ISO C threads API. +dnl Sets the variable LIBSTDTHREAD to the linker options for use in a Makefile. +dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for +dnl multithread-safe programs. +dnl Defines the C macro HAVE_THREADS_H if (at least parts of) the ISO C threads +dnl API is available. + +dnl The guts of gl_STDTHREADLIB. Needs to be expanded only once. + +AC_DEFUN([gl_STDTHREADLIB_BODY], +[ + AC_REQUIRE([gl_ANYTHREADLIB_EARLY]) + AC_REQUIRE([AC_CANONICAL_HOST]) + if test -z "$gl_stdthreadlib_body_done"; then + AC_CHECK_HEADERS_ONCE([threads.h]) + + case "$host_os" in + mingw*) + LIBSTDTHREAD= + ;; + *) + gl_PTHREADLIB_BODY + if test $ac_cv_header_threads_h = yes; then + dnl glibc >= 2.29 has thrd_create in libpthread. + dnl FreeBSD >= 10 has thrd_create in libstdthreads; this library depends + dnl on libpthread (for the symbol 'pthread_mutexattr_gettype'). + dnl AIX >= 7.1 and Solaris >= 11.4 have thrd_create in libc. + AC_CHECK_FUNCS([thrd_create]) + if test $ac_cv_func_thrd_create = yes; then + LIBSTDTHREAD= + else + AC_CHECK_LIB([stdthreads], [thrd_create], [ + LIBSTDTHREAD='-lstdthreads -lpthread' + ], [ + dnl Guess that thrd_create is in libpthread. + LIBSTDTHREAD="$LIBPMULTITHREAD" + ]) + fi + else + dnl Libraries needed by thrd.c, mtx.c, cnd.c, tss.c. + LIBSTDTHREAD="$LIBPMULTITHREAD $LIB_SCHED_YIELD" + fi + ;; + esac + AC_SUBST([LIBSTDTHREAD]) + + AC_MSG_CHECKING([whether ISO C threads API is available]) + AC_MSG_RESULT([$ac_cv_header_threads_h]) + gl_stdthreadlib_body_done=done + fi +]) + +AC_DEFUN([gl_STDTHREADLIB], +[ + AC_REQUIRE([gl_ANYTHREADLIB_EARLY]) + gl_STDTHREADLIB_BODY +]) + +dnl ============================================================================ +dnl Macros for the Gnulib API + +dnl gl_THREADLIB +dnl ------------ +dnl Tests for a multithreading library to be used. +dnl If the configure.ac contains a definition of the gl_THREADLIB_DEFAULT_NO +dnl (it must be placed before the invocation of gl_THREADLIB_EARLY!), then the +dnl default is 'no', otherwise it is system dependent. In both cases, the user +dnl can change the choice through the options --enable-threads=choice or +dnl --disable-threads. +dnl Defines at most one of the macros USE_ISOC_THREADS, USE_POSIX_THREADS, +dnl USE_ISOC_AND_POSIX_THREADS, USE_WINDOWS_THREADS. +dnl The choice --enable-threads=isoc+posix is available only on platforms that +dnl have both the ISO C and the POSIX threads APIs. It has the effect of using +dnl the ISO C API for most things and the POSIX API only for creating and +dnl controlling threads (because there is no equivalent to pthread_atfork in +dnl the ISO C API). +dnl Sets the variables LIBTHREAD and LTLIBTHREAD to the linker options for use +dnl in a Makefile (LIBTHREAD for use without libtool, LTLIBTHREAD for use with +dnl libtool). +dnl Sets the variables LIBMULTITHREAD and LTLIBMULTITHREAD similarly, for +dnl programs that really need multithread functionality. The difference +dnl between LIBTHREAD and LIBMULTITHREAD is that on platforms supporting weak +dnl symbols, typically LIBTHREAD is empty whereas LIBMULTITHREAD is not. +dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for +dnl multithread-safe programs. +dnl Since support for GNU pth was removed, $LTLIBTHREAD and $LIBTHREAD have the +dnl same value, and similarly $LTLIBMULTITHREAD and $LIBMULTITHREAD have the +dnl same value. Only system libraries are needed. + +AC_DEFUN([gl_THREADLIB_EARLY], +[ + AC_REQUIRE([gl_THREADLIB_EARLY_BODY]) +]) + +dnl The guts of gl_THREADLIB_EARLY. Needs to be expanded only once. + +AC_DEFUN([gl_THREADLIB_EARLY_BODY], +[ + dnl Ordering constraints: This macro modifies CPPFLAGS in a way that + dnl influences the result of the autoconf tests that test for *_unlocked + dnl declarations, on AIX 5 at least. Therefore it must come early. + AC_BEFORE([$0], [gl_FUNC_GLIBC_UNLOCKED_IO])dnl + AC_BEFORE([$0], [gl_ARGP])dnl + + AC_REQUIRE([AC_CANONICAL_HOST]) + dnl _GNU_SOURCE is needed for pthread_rwlock_t on glibc systems. + AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) + dnl Check for multithreading. + m4_ifdef([gl_THREADLIB_DEFAULT_NO], + [m4_divert_text([DEFAULTS], [gl_use_threads_default=no])], + [m4_divert_text([DEFAULTS], [gl_use_threads_default=])]) + m4_divert_text([DEFAULTS], [gl_use_winpthreads_default=]) + AC_ARG_ENABLE([threads], +AC_HELP_STRING([--enable-threads={isoc|posix|isoc+posix|windows}], [specify multithreading API])m4_ifdef([gl_THREADLIB_DEFAULT_NO], [], [ +AC_HELP_STRING([--disable-threads], [build without multithread safety])]), + [gl_use_threads=$enableval], + [if test -n "$gl_use_threads_default"; then + gl_use_threads="$gl_use_threads_default" + else +changequote(,)dnl + case "$host_os" in + dnl Disable multithreading by default on OSF/1, because it interferes + dnl with fork()/exec(): When msgexec is linked with -lpthread, its + dnl child process gets an endless segmentation fault inside execvp(). + osf*) gl_use_threads=no ;; + dnl Disable multithreading by default on Cygwin 1.5.x, because it has + dnl bugs that lead to endless loops or crashes. See + dnl <https://cygwin.com/ml/cygwin/2009-08/msg00283.html>. + cygwin*) + case `uname -r` in + 1.[0-5].*) gl_use_threads=no ;; + *) gl_use_threads=yes ;; + esac + ;; + dnl Obey gl_AVOID_WINPTHREAD on mingw. + mingw*) + case "$gl_use_winpthreads_default" in + yes) gl_use_threads=posix ;; + no) gl_use_threads=windows ;; + *) gl_use_threads=yes ;; + esac + ;; + *) gl_use_threads=yes ;; + esac +changequote([,])dnl + fi + ]) + if test "$gl_use_threads" = yes \ + || test "$gl_use_threads" = isoc \ + || test "$gl_use_threads" = posix \ + || test "$gl_use_threads" = isoc+posix; then + # For using <threads.h> or <pthread.h>: + gl_ANYTHREADLIB_EARLY fi ]) @@ -303,20 +463,7 @@ AC_DEFUN([gl_THREADLIB_BODY], fi if test "$gl_use_threads" = isoc || test "$gl_use_threads" = isoc+posix; then AC_CHECK_HEADERS_ONCE([threads.h]) - if test $ac_cv_header_threads_h = yes; then - gl_have_isoc_threads= - # Test whether both mtx_lock and cnd_timedwait exist in libc. - AC_LINK_IFELSE( - [AC_LANG_PROGRAM( - [[#include <threads.h> - #include <stddef.h> - mtx_t m; - cnd_t c; - ]], - [[mtx_lock (&m); - cnd_timedwait (&c, &m, NULL);]])], - [gl_have_isoc_threads=yes]) - fi + gl_have_isoc_threads="$ac_cv_header_threads_h" fi if test "$gl_use_threads" = yes \ || test "$gl_use_threads" = posix \ @@ -346,6 +493,9 @@ AC_DEFUN([gl_THREADLIB_BODY], fi if test $gl_threads_api = none; then if test "$gl_use_threads" = isoc && test "$gl_have_isoc_threads" = yes; then + gl_STDTHREADLIB_BODY + LIBTHREAD=$LIBSTDTHREAD LTLIBTHREAD=$LIBSTDTHREAD + LIBMULTITHREAD=$LIBSTDTHREAD LTLIBMULTITHREAD=$LIBSTDTHREAD gl_threads_api=isoc AC_DEFINE([USE_ISOC_THREADS], [1], [Define if the ISO C multithreading library can be used.]) @@ -375,12 +525,6 @@ AC_DEFUN([gl_THREADLIB_BODY], AC_SUBST([LTLIBMULTITHREAD]) ]) -AC_DEFUN([gl_PTHREADLIB], -[ - AC_REQUIRE([gl_ANYTHREADLIB_EARLY]) - gl_PTHREADLIB_BODY -]) - AC_DEFUN([gl_THREADLIB], [ AC_REQUIRE([gl_THREADLIB_EARLY]) @@ -411,6 +555,9 @@ AC_DEFUN([gl_AVOID_WINPTHREAD], [ ]) +dnl ============================================================================ + + dnl Survey of platforms: dnl dnl Platform Available Compiler Supports test-lock |