From 5741c45acf9b0ce22ff0dbf56322fe0ff16cfcfc Mon Sep 17 00:00:00 2001 From: Neil Schemenauer Date: Fri, 8 Feb 2019 10:48:46 -0800 Subject: bpo-35903: Use autoconfig to probe for shm_open() and shm_unlink(). (#11765) Use autoconfig to probe for shm_open() and shm_unlink(). Set SHM_NEEDS_LIBRT if we must link with librt to get the shm_* functions. Change setup.py to use the autoconfig defines. These changes should make it more likely that _multiprocessing/posixshmem.c gets built correctly on different platforms. --- configure | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ configure.ac | 24 ++++++++++++++ pyconfig.h.in | 12 +++++++ setup.py | 7 ++-- 4 files changed, 142 insertions(+), 3 deletions(-) diff --git a/configure b/configure index ebd9f90..b78a7b2 100755 --- a/configure +++ b/configure @@ -16862,6 +16862,108 @@ $as_echo "#define HAVE_GETRANDOM 1" >>confdefs.h fi +# checks for POSIX shared memory, used by Modules/_multiprocessing/posixshmem.c +# shm_* may only be available if linking against librt +save_LIBS="$LIBS" +save_includes_default="$ac_includes_default" +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing shm_open" >&5 +$as_echo_n "checking for library containing shm_open... " >&6; } +if ${ac_cv_search_shm_open+:} false; then : + $as_echo_n "(cached) " >&6 +else + ac_func_search_save_LIBS=$LIBS +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +/* Override any GCC internal prototype to avoid an error. + Use char because int might match the return type of a GCC + builtin and then its argument prototype would still apply. */ +#ifdef __cplusplus +extern "C" +#endif +char shm_open (); +int +main () +{ +return shm_open (); + ; + return 0; +} +_ACEOF +for ac_lib in '' rt; do + if test -z "$ac_lib"; then + ac_res="none required" + else + ac_res=-l$ac_lib + LIBS="-l$ac_lib $ac_func_search_save_LIBS" + fi + if ac_fn_c_try_link "$LINENO"; then : + ac_cv_search_shm_open=$ac_res +fi +rm -f core conftest.err conftest.$ac_objext \ + conftest$ac_exeext + if ${ac_cv_search_shm_open+:} false; then : + break +fi +done +if ${ac_cv_search_shm_open+:} false; then : + +else + ac_cv_search_shm_open=no +fi +rm conftest.$ac_ext +LIBS=$ac_func_search_save_LIBS +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_shm_open" >&5 +$as_echo "$ac_cv_search_shm_open" >&6; } +ac_res=$ac_cv_search_shm_open +if test "$ac_res" != no; then : + test "$ac_res" = "none required" || LIBS="$ac_res $LIBS" + +fi + +if test "$ac_cv_search_shm_open" = "-lrt"; then + +$as_echo "#define SHM_NEEDS_LIBRT 1" >>confdefs.h + +fi +for ac_header in sys/mman.h +do : + ac_fn_c_check_header_mongrel "$LINENO" "sys/mman.h" "ac_cv_header_sys_mman_h" "$ac_includes_default" +if test "x$ac_cv_header_sys_mman_h" = xyes; then : + cat >>confdefs.h <<_ACEOF +#define HAVE_SYS_MMAN_H 1 +_ACEOF + +fi + +done + +# temporarily override ac_includes_default for AC_CHECK_FUNCS below +ac_includes_default="\ +${ac_includes_default} +#ifndef __cplusplus +# ifdef HAVE_SYS_MMAN_H +# include +# endif +#endif +" +for ac_func in shm_open shm_unlink +do : + as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh` +ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var" +if eval test \"x\$"$as_ac_var"\" = x"yes"; then : + cat >>confdefs.h <<_ACEOF +#define `$as_echo "HAVE_$ac_func" | $as_tr_cpp` 1 +_ACEOF + +fi +done + +# we don't want to link with librt always, restore LIBS +LIBS="$save_LIBS" +ac_includes_default="$save_includes_default" + # Check for usable OpenSSL found=false diff --git a/configure.ac b/configure.ac index 721edb0..eeedfed 100644 --- a/configure.ac +++ b/configure.ac @@ -5443,6 +5443,30 @@ if test "$have_getrandom" = yes; then [Define to 1 if the getrandom() function is available]) fi +# checks for POSIX shared memory, used by Modules/_multiprocessing/posixshmem.c +# shm_* may only be available if linking against librt +save_LIBS="$LIBS" +save_includes_default="$ac_includes_default" +AC_SEARCH_LIBS(shm_open, rt) +if test "$ac_cv_search_shm_open" = "-lrt"; then + AC_DEFINE(SHM_NEEDS_LIBRT, 1, + [Define to 1 if you must link with -lrt for shm_open().]) +fi +AC_CHECK_HEADERS(sys/mman.h) +# temporarily override ac_includes_default for AC_CHECK_FUNCS below +ac_includes_default="\ +${ac_includes_default} +#ifndef __cplusplus +# ifdef HAVE_SYS_MMAN_H +# include +# endif +#endif +" +AC_CHECK_FUNCS([shm_open shm_unlink]) +# we don't want to link with librt always, restore LIBS +LIBS="$save_LIBS" +ac_includes_default="$save_includes_default" + # Check for usable OpenSSL AX_CHECK_OPENSSL([have_openssl=yes],[have_openssl=no]) diff --git a/pyconfig.h.in b/pyconfig.h.in index a2a5623..ab9e9e1 100644 --- a/pyconfig.h.in +++ b/pyconfig.h.in @@ -144,6 +144,18 @@ /* Define to 1 if you have the `copysign' function. */ #undef HAVE_COPYSIGN +/* Define to 1 if you must link with -lrt for shm_open(). */ +#undef SHM_NEEDS_LIBRT + +/* Define to 1 if you have the header file. */ +#undef HAVE_SYS_MMAN_H + +/* Define to 1 if you have the shm_open syscall */ +#undef HAVE_SHM_OPEN + +/* Define to 1 if you have the shm_unlink syscall */ +#undef HAVE_SHM_UNLINK + /* Define to 1 if you have the header file. */ #undef HAVE_CRYPT_H diff --git a/setup.py b/setup.py index d54bbe0..4a01a8f 100644 --- a/setup.py +++ b/setup.py @@ -1592,12 +1592,13 @@ class PyBuildExt(build_ext): if (sysconfig.get_config_var('HAVE_SEM_OPEN') and not sysconfig.get_config_var('POSIX_SEMAPHORES_NOT_ENABLED')): multiprocessing_srcs.append('_multiprocessing/semaphore.c') - if (self.compiler.find_library_file(lib_dirs, 'rt') or - host_platform != 'cygwin'): + if (sysconfig.get_config_var('HAVE_SHM_OPEN') and + sysconfig.get_config_var('HAVE_SHM_UNLINK')): posixshmem_srcs = [ '_multiprocessing/posixshmem.c', ] libs = [] - if self.compiler.find_library_file(lib_dirs, 'rt'): + if sysconfig.get_config_var('SHM_NEEDS_LIBRT'): + # need to link with librt to get shm_open() libs.append('rt') exts.append( Extension('_posixshmem', posixshmem_srcs, define_macros={}, -- cgit v0.12