From 9cc85a4f52147fcdaa4c52a62bcc87bdb267d0a9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Wed, 29 Mar 2023 11:21:38 +0200 Subject: Use 'posix_spawn_file_actions_addclosefrom_np' where available. * configure.ac: Check for 'posix_spawn_file_actions_addclosefrom_np'. * libguile/posix.c (HAVE_ADDCLOSEFROM): New macro. (close_inherited_fds): Wrap in #ifdef HAVE_ADDCLOSEFROM. (do_spawn) [HAVE_ADDCLOSEFROM]: Use 'posix_spawn_file_actions_addclosefrom_np'. --- configure.ac | 4 +++- libguile/posix.c | 14 ++++++++++++++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/configure.ac b/configure.ac index d5ce1c4ac..4a93be979 100644 --- a/configure.ac +++ b/configure.ac @@ -515,6 +515,7 @@ AC_CHECK_HEADERS([crt_externs.h]) # sched_getaffinity, sched_setaffinity - GNU extensions (glibc) # sendfile - non-POSIX, found in glibc # pipe2 - non-POSIX, found in glibc (GNU/Linux and GNU/Hurd) +# posix_spawn_file_actions_addclosefrom_np - glibc >= 2.34 # AC_CHECK_FUNCS([DINFINITY DQNAN cexp chsize clog clog10 ctermid \ fesetround ftime ftruncate fchown fchownat fchmod fchdir readlinkat \ @@ -528,7 +529,8 @@ AC_CHECK_FUNCS([DINFINITY DQNAN cexp chsize clog clog10 ctermid \ index bcopy rindex truncate isblank _NSGetEnviron \ strcoll_l strtod_l strtol_l newlocale uselocale utimensat \ fstatat futimens openat \ - sched_getaffinity sched_setaffinity sendfile pipe2]) + sched_getaffinity sched_setaffinity sendfile pipe2 + posix_spawn_file_actions_addclosefrom_np]) # The newlib C library uses _NL_ prefixed locale langinfo constants. AC_CHECK_DECLS([_NL_NUMERIC_GROUPING], [], [], [[#include ]]) diff --git a/libguile/posix.c b/libguile/posix.c index b5830c43b..3adc743c4 100644 --- a/libguile/posix.c +++ b/libguile/posix.c @@ -1322,6 +1322,12 @@ SCM_DEFINE (scm_fork, "primitive-fork", 0, 0, 0, #undef FUNC_NAME #endif /* HAVE_FORK */ +#ifdef HAVE_POSIX_SPAWN_FILE_ACTIONS_ADDCLOSEFROM_NP +# define HAVE_ADDCLOSEFROM 1 +#endif + +#ifndef HAVE_ADDCLOSEFROM + static void close_inherited_fds (posix_spawn_file_actions_t *actions, int max_fd) { @@ -1346,6 +1352,8 @@ close_inherited_fds (posix_spawn_file_actions_t *actions, int max_fd) } } +#endif + static pid_t do_spawn (char *exec_file, char **exec_argv, char **exec_env, int in, int out, int err, int spawnp) @@ -1389,7 +1397,13 @@ do_spawn (char *exec_file, char **exec_argv, char **exec_env, posix_spawn_file_actions_adddup2 (&actions, fd_slot[1], 1); posix_spawn_file_actions_adddup2 (&actions, fd_slot[2], 2); +#ifdef HAVE_ADDCLOSEFROM + /* This function appears in glibc 2.34. It's both free from race + conditions and more efficient than the alternative. */ + posix_spawn_file_actions_addclosefrom_np (&actions, 3); +#else close_inherited_fds (&actions, max_fd); +#endif int res = -1; if (spawnp) -- cgit v1.2.1