libiberty: Use posix_spawn in pex-unix when available.

Hi,

This patch implements pex_unix_exec_child using posix_spawn when
available.

This should especially benefit recent macOS (where vfork just calls
fork), but should have equivalent or faster performance on all
platforms.
In addition, the implementation is substantially simpler than the
vfork+exec code path.

Tested on x86_64-linux.

v2: Fix error handling (previously the function would be run twice in
case of error), and don't use a macro that changes control flow.

v3: Match file style for error-handling blocks, don't close
in/out/errdes on error, and check close() for errors.

libiberty/
	* configure.ac (AC_CHECK_HEADERS): Add spawn.h.
	(checkfuncs): Add posix_spawn, posix_spawnp.
	(AC_CHECK_FUNCS): Add posix_spawn, posix_spawnp.
	* aclocal.m4, configure, config.in: Rebuild.
	* pex-unix.c [HAVE_POSIX_SPAWN] (pex_unix_exec_child): New function.
This commit is contained in:
Brendan Shanks
2023-11-09 21:01:07 -07:00
committed by Augustin Cavalier
parent 360fe2fd07
commit 7ab022f6e6
5 changed files with 189 additions and 8 deletions

View File

@@ -277,7 +277,7 @@ AC_SUBST_FILE(host_makefile_frag)
# It's OK to check for header files. Although the compiler may not be
# able to link anything, it had better be able to at least compile
# something.
AC_CHECK_HEADERS(sys/file.h sys/param.h limits.h stdlib.h malloc.h string.h unistd.h strings.h sys/time.h time.h sys/resource.h sys/stat.h sys/mman.h fcntl.h alloca.h sys/pstat.h sys/sysmp.h sys/sysinfo.h machine/hal_sysinfo.h sys/table.h sys/sysctl.h sys/systemcfg.h stdint.h stdio_ext.h process.h sys/prctl.h)
AC_CHECK_HEADERS(sys/file.h sys/param.h limits.h stdlib.h malloc.h string.h unistd.h strings.h sys/time.h time.h sys/resource.h sys/stat.h sys/mman.h fcntl.h alloca.h sys/pstat.h sys/sysmp.h sys/sysinfo.h machine/hal_sysinfo.h sys/table.h sys/sysctl.h sys/systemcfg.h stdint.h stdio_ext.h process.h sys/prctl.h spawn.h)
AC_HEADER_SYS_WAIT
AC_HEADER_TIME
@@ -400,7 +400,8 @@ funcs="$funcs setproctitle"
vars="sys_errlist sys_nerr sys_siglist"
checkfuncs="__fsetlocking canonicalize_file_name dup3 getrlimit getrusage \
getsysinfo gettimeofday on_exit pipe2 psignal pstat_getdynamic pstat_getstatic \
getsysinfo gettimeofday on_exit pipe2 posix_spawn posix_spawnp psignal \
pstat_getdynamic pstat_getstatic \
realpath setrlimit spawnve spawnvpe strerror strsignal sysconf sysctl \
sysmp table times wait3 wait4"
@@ -423,7 +424,8 @@ if test "x" = "y"; then
index insque \
memchr memcmp memcpy memmem memmove memset mkstemps \
on_exit \
pipe2 psignal pstat_getdynamic pstat_getstatic putenv \
pipe2 posix_spawn posix_spawnp psignal \
pstat_getdynamic pstat_getstatic putenv \
random realpath rename rindex \
sbrk setenv setproctitle setrlimit sigsetmask snprintf spawnve spawnvpe \
stpcpy stpncpy strcasecmp strchr strdup \