binutils-gdb/libiberty/pex-unix.c
Nick Clifton e2a2633945 Synchronize sourceware version of the libiberty sources with the master gcc versions.
This brings in the following commits:

commit c73cc6fe6207b2863afa31a3be8ad87b70d3df0a
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Tue Dec 5 23:32:19 2023 +0100

    libiberty: Fix build with GCC < 7

    Tobias reported on IRC that the linker fails to build with GCC 4.8.5.
    In configure I've tried to use everything actually used in the sha1.c
    x86 hw implementation, but unfortunately I forgot about implicit function
    declarations.  GCC before 7 did have <cpuid.h> header and bit_SHA define
    and __get_cpuid function defined inline, but it didn't define
    __get_cpuid_count, which compiled fine (and the configure test is
    intentionally compile time only) due to implicit function declaration,
    but then failed to link when linking the linker, because
    __get_cpuid_count wasn't defined anywhere.

    The following patch fixes that by using what autoconf uses in AC_CHECK_DECL
    to make sure the functions are declared.

commit 691858d279335eeeeed3afafdf872b1c5f8f4201
Author: Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
Date:   Tue Dec 5 11:04:06 2023 +0100

    libiberty: Fix pex_unix_wait return type

    The recent warning patches broke Solaris bootstrap:

    /vol/gcc/src/hg/master/local/libiberty/pex-unix.c:326:3: error: initialization of 'pid_t (*)(struct pex_obj *, pid_t,  int *, struct pex_time *, int,  const char **, int *)' {aka 'long int (*)(struct pex_obj *, long int,  int *, struct pex_time *, int,  const char **, int *)'} from incompatible pointer type 'int (*)(struct pex_obj *, pid_t,  int *, struct pex_time *, int,  const char **, int *)' {aka 'int (*)(struct pex_obj *, long int,  int *, struct pex_time *, int,  const char **, int *)'} [-Wincompatible-pointer-types]
      326 |   pex_unix_wait,
          |   ^~~~~~~~~~~~~
    /vol/gcc/src/hg/master/local/libiberty/pex-unix.c:326:3: note: (near initialization for 'funcs.wait')

    While pex_funcs.wait expects a function returning pid_t, pex_unix_wait
    currently returns int.  However, on Solaris pid_t is long for 32-bit,
    but int for 64-bit.

    This patches fixes this by having pex_unix_wait return pid_t as
    expected, and like every other variant already does.

    Bootstrapped without regressions on i386-pc-solaris2.11,
    sparc-sun-solaris2.11, x86_64-pc-linux-gnu, and
    x86_64-apple-darwin23.1.0.

commit c3f281a0c1ca50e4df5049923aa2f5d1c3c39ff6
Author: Jason Merrill <jason@redhat.com>
Date:   Mon Sep 25 10:15:02 2023 +0100

    c++: mangle function template constraints

    Per https://github.com/itanium-cxx-abi/cxx-abi/issues/24 and
    https://github.com/itanium-cxx-abi/cxx-abi/pull/166

    We need to mangle constraints to be able to distinguish between function
    templates that only differ in constraints.  From the latter link, we want to
    use the template parameter mangling previously specified for lambdas to also
    make explicit the form of a template parameter where the argument is not a
    "natural" fit for it, such as when the parameter is constrained or deduced.

    I'm concerned about how the latter link changes the mangling for some C++98
    and C++11 patterns, so I've limited template_parm_natural_p to avoid two
    cases found by running the testsuite with -Wabi forced on:

    template <class T, T V> T f() { return V; }
    int main() { return f<int,42>(); }

    template <int i> int max() { return i; }
    template <int i, int j, int... rest> int max()
    {
      int sub = max<j, rest...>();
      return i > sub ? i : sub;
    }
    int main() {  return max<1,2,3>(); }

    A third C++11 pattern is changed by this patch:

    template <template <typename...> class TT, typename... Ts> TT<Ts...> f();
    template <typename> struct A { };
    int main() { f<A,int>(); }

    I aim to resolve these with the ABI committee before GCC 14.1.

    We also need to resolve https://github.com/itanium-cxx-abi/cxx-abi/issues/38
    (mangling references to dependent template-ids where the name is fully
    resolved) as references to concepts in std:: will consistently run into this
    area.  This is why mangle-concepts1.C only refers to concepts in the global
    namespace so far.

    The library changes are to avoid trying to mangle builtins, which fails.

    Demangler support and test coverage is not complete yet.

commit f2c52c0dfde581461959b0e2b423ad106aadf179
Author: Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
Date:   Thu Nov 30 10:06:23 2023 +0100

    libiberty: Disable hwcaps for sha1.o

    This patch

    commit bf4f40cc3195eb7b900bf5535cdba1ee51fdbb8e
    Author: Jakub Jelinek <jakub@redhat.com>
    Date:   Tue Nov 28 13:14:05 2023 +0100

        libiberty: Use x86 HW optimized sha1

    broke Solaris/x86 bootstrap with the native as:

    libtool: compile:  /var/gcc/regression/master/11.4-gcc/build/./gcc/gccgo -B/var/gcc/regression/master/11.4-gcc/build/./gcc/ -B/vol/gcc/i386-pc-solaris2.11/bin/ -B/vol/gcc/i386-pc-solaris2.11/lib/ -isystem /vol/gcc/i386-pc-solaris2.11/include -isystem /vol/gcc/i386-pc-solaris2.11/sys-include -fchecking=1 -minline-all-stringops -O2 -g -I . -c -fgo-pkgpath=internal/goarch /vol/gcc/src/hg/master/local/libgo/go/internal/goarch/goarch.go zgoarch.go
    ld.so.1: go1: fatal: /var/gcc/regression/master/11.4-gcc/build/gcc/go1: hardware capability (CA_SUNW_HW_2) unsupported: 0x4000000  [ SHA1 ]
    gccgo: fatal error: Killed signal terminated program go1

    As is already done in a couple of other similar cases, this patches
    disables hwcaps support for libiberty.

    Initially, this didn't work because config/hwcaps.m4 uses target_os, but
    didn't ensure it is defined.

    Tested on i386-pc-solaris2.11 with as and gas.

commit bf4f40cc3195eb7b900bf5535cdba1ee51fdbb8e
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Tue Nov 28 13:14:05 2023 +0100

    libiberty: Use x86 HW optimized sha1

    Nick has approved this patch (+ small ld change to use it for --build-id=),
    so I'm commiting it to GCC as master as well.

    If anyone from ARM would be willing to implement it similarly with
    vsha1{cq,mq,pq,h,su0q,su1q}_u32 intrinsics, it could be a useful linker
    speedup on those hosts as well, the intent in sha1.c was that
    sha1_hw_process_bytes, sha1_hw_process_block functions
    would be defined whenever
    defined (HAVE_X86_SHA1_HW_SUPPORT) || defined (HAVE_WHATEVERELSE_SHA1_HW_SUPPORT)
    but the body of sha1_hw_process_block and sha1_choose_process_bytes
    would then have #elif defined (HAVE_WHATEVERELSE_SHA1_HW_SUPPORT) for
    the other arch support, similarly for any target attributes on
    sha1_hw_process_block if needed.

commit 01bc30b222a9d2ff0269325d9e367f8f1fcef942
Author: Mark Wielaard <mjw@redhat.com>
Date:   Wed Nov 15 20:27:08 2023 +0100

    Regenerate libiberty/aclocal.m4 with aclocal 1.15.1

    There is a new buildbot check that all autotool files are generated
    with the correct versions (automake 1.15.1 and autoconf 2.69).
    https://builder.sourceware.org/buildbot/#/builders/gcc-autoregen

    Correct one file that was generated with the wrong version.

commit 879cf9ff45d94065d89e24b71c6b27c7076ac518
Author: Brendan Shanks <bshanks@codeweavers.com>
Date:   Thu Nov 9 21:01:07 2023 -0700

    [PATCH v3] 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.

commit 810bcc00156cefce7ad40fc9d8de6e43c3a04450
Author: Jason Merrill <jason@redhat.com>
Date:   Thu Aug 17 11:36:23 2023 -0400

    c++: constrained hidden friends [PR109751]

    r13-4035 avoided a problem with overloading of constrained hidden friends by
    checking satisfaction, but checking satisfaction early is inconsistent with
    the usual late checking and can lead to hard errors, so let's not do that
    after all.

    We were wrongly treating the different instantiations of the same friend
    template as the same function because maybe_substitute_reqs_for was failing
    to actually substitute in the case of a non-template friend.  But we don't
    actually need to do the substitution anyway, because [temp.friend] says that
    such a friend can't be the same as any other declaration.

    After fixing that, instead of a redefinition error we got an ambiguous
    overload error, fixed by allowing constrained hidden friends to coexist
    until overload resolution, at which point they probably won't be in the same
    ADL overload set anyway.

    And we avoid mangling collisions by following the proposed mangling for
    these friends as a member function with an extra 'F' before the name.  I
    demangle this by just adding [friend] to the name of the function because
    it's not feasible to reconstruct the actual scope of the function since the
    mangling ABI doesn't distinguish between class and namespace scopes.

            PR c++/109751
2024-01-09 12:34:00 +00:00

1000 lines
24 KiB
C

/* Utilities to execute a program in a subprocess (possibly linked by pipes
with other subprocesses), and wait for it. Generic Unix version
(also used for UWIN and VMS).
Copyright (C) 1996-2024 Free Software Foundation, Inc.
This file is part of the libiberty library.
Libiberty is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
Libiberty is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with libiberty; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
Boston, MA 02110-1301, USA. */
#include "config.h"
#include "libiberty.h"
#include "pex-common.h"
#include "environ.h"
#include <stdio.h>
#include <signal.h>
#include <errno.h>
#ifdef NEED_DECLARATION_ERRNO
extern int errno;
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifdef HAVE_GETRUSAGE
#include <sys/time.h>
#include <sys/resource.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_PROCESS_H
#include <process.h>
#endif
#ifdef HAVE_SPAWN_H
#include <spawn.h>
#endif
#ifdef vfork /* Autoconf may define this to fork for us. */
# define VFORK_STRING "fork"
#else
# define VFORK_STRING "vfork"
#endif
#ifdef HAVE_VFORK_H
#include <vfork.h>
#endif
#if defined(VMS) && defined (__LONG_POINTERS)
#ifndef __CHAR_PTR32
typedef char * __char_ptr32
__attribute__ ((mode (SI)));
#endif
typedef __char_ptr32 *__char_ptr_char_ptr32
__attribute__ ((mode (SI)));
/* Return a 32 bit pointer to an array of 32 bit pointers
given a 64 bit pointer to an array of 64 bit pointers. */
static __char_ptr_char_ptr32
to_ptr32 (char **ptr64)
{
int argc;
__char_ptr_char_ptr32 short_argv;
/* Count number of arguments. */
for (argc = 0; ptr64[argc] != NULL; argc++)
;
/* Reallocate argv with 32 bit pointers. */
short_argv = (__char_ptr_char_ptr32) decc$malloc
(sizeof (__char_ptr32) * (argc + 1));
for (argc = 0; ptr64[argc] != NULL; argc++)
short_argv[argc] = (__char_ptr32) decc$strdup (ptr64[argc]);
short_argv[argc] = (__char_ptr32) 0;
return short_argv;
}
#else
#define to_ptr32(argv) argv
#endif
/* File mode to use for private and world-readable files. */
#if defined (S_IRUSR) && defined (S_IWUSR) && defined (S_IRGRP) && defined (S_IWGRP) && defined (S_IROTH) && defined (S_IWOTH)
#define PUBLIC_MODE \
(S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)
#else
#define PUBLIC_MODE 0666
#endif
/* Get the exit status of a particular process, and optionally get the
time that it took. This is simple if we have wait4, slightly
harder if we have waitpid, and is a pain if we only have wait. */
static pid_t pex_wait (struct pex_obj *, pid_t, int *, struct pex_time *);
#ifdef HAVE_WAIT4
static pid_t
pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status,
struct pex_time *time)
{
pid_t ret;
struct rusage r;
#ifdef HAVE_WAITPID
if (time == NULL)
return waitpid (pid, status, 0);
#endif
ret = wait4 (pid, status, 0, &r);
if (time != NULL)
{
time->user_seconds = r.ru_utime.tv_sec;
time->user_microseconds= r.ru_utime.tv_usec;
time->system_seconds = r.ru_stime.tv_sec;
time->system_microseconds= r.ru_stime.tv_usec;
}
return ret;
}
#else /* ! defined (HAVE_WAIT4) */
#ifdef HAVE_WAITPID
#ifndef HAVE_GETRUSAGE
static pid_t
pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status,
struct pex_time *time)
{
if (time != NULL)
memset (time, 0, sizeof (struct pex_time));
return waitpid (pid, status, 0);
}
#else /* defined (HAVE_GETRUSAGE) */
static pid_t
pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status,
struct pex_time *time)
{
struct rusage r1, r2;
pid_t ret;
if (time == NULL)
return waitpid (pid, status, 0);
getrusage (RUSAGE_CHILDREN, &r1);
ret = waitpid (pid, status, 0);
if (ret < 0)
return ret;
getrusage (RUSAGE_CHILDREN, &r2);
time->user_seconds = r2.ru_utime.tv_sec - r1.ru_utime.tv_sec;
time->user_microseconds = r2.ru_utime.tv_usec - r1.ru_utime.tv_usec;
if (r2.ru_utime.tv_usec < r1.ru_utime.tv_usec)
{
--time->user_seconds;
time->user_microseconds += 1000000;
}
time->system_seconds = r2.ru_stime.tv_sec - r1.ru_stime.tv_sec;
time->system_microseconds = r2.ru_stime.tv_usec - r1.ru_stime.tv_usec;
if (r2.ru_stime.tv_usec < r1.ru_stime.tv_usec)
{
--time->system_seconds;
time->system_microseconds += 1000000;
}
return ret;
}
#endif /* defined (HAVE_GETRUSAGE) */
#else /* ! defined (HAVE_WAITPID) */
struct status_list
{
struct status_list *next;
pid_t pid;
int status;
struct pex_time time;
};
static pid_t
pex_wait (struct pex_obj *obj, pid_t pid, int *status, struct pex_time *time)
{
struct status_list **pp;
for (pp = (struct status_list **) &obj->sysdep;
*pp != NULL;
pp = &(*pp)->next)
{
if ((*pp)->pid == pid)
{
struct status_list *p;
p = *pp;
*status = p->status;
if (time != NULL)
*time = p->time;
*pp = p->next;
free (p);
return pid;
}
}
while (1)
{
pid_t cpid;
struct status_list *psl;
struct pex_time pt;
#ifdef HAVE_GETRUSAGE
struct rusage r1, r2;
#endif
if (time != NULL)
{
#ifdef HAVE_GETRUSAGE
getrusage (RUSAGE_CHILDREN, &r1);
#else
memset (&pt, 0, sizeof (struct pex_time));
#endif
}
cpid = wait (status);
#ifdef HAVE_GETRUSAGE
if (time != NULL && cpid >= 0)
{
getrusage (RUSAGE_CHILDREN, &r2);
pt.user_seconds = r2.ru_utime.tv_sec - r1.ru_utime.tv_sec;
pt.user_microseconds = r2.ru_utime.tv_usec - r1.ru_utime.tv_usec;
if (pt.user_microseconds < 0)
{
--pt.user_seconds;
pt.user_microseconds += 1000000;
}
pt.system_seconds = r2.ru_stime.tv_sec - r1.ru_stime.tv_sec;
pt.system_microseconds = r2.ru_stime.tv_usec - r1.ru_stime.tv_usec;
if (pt.system_microseconds < 0)
{
--pt.system_seconds;
pt.system_microseconds += 1000000;
}
}
#endif
if (cpid < 0 || cpid == pid)
{
if (time != NULL)
*time = pt;
return cpid;
}
psl = XNEW (struct status_list);
psl->pid = cpid;
psl->status = *status;
if (time != NULL)
psl->time = pt;
psl->next = (struct status_list *) obj->sysdep;
obj->sysdep = (void *) psl;
}
}
#endif /* ! defined (HAVE_WAITPID) */
#endif /* ! defined (HAVE_WAIT4) */
static int pex_unix_open_read (struct pex_obj *, const char *, int);
static int pex_unix_open_write (struct pex_obj *, const char *, int, int);
static pid_t pex_unix_exec_child (struct pex_obj *, int, const char *,
char * const *, char * const *,
int, int, int, int,
const char **, int *);
static int pex_unix_close (struct pex_obj *, int);
static pid_t pex_unix_wait (struct pex_obj *, pid_t, int *, struct pex_time *,
int, const char **, int *);
static int pex_unix_pipe (struct pex_obj *, int *, int);
static FILE *pex_unix_fdopenr (struct pex_obj *, int, int);
static FILE *pex_unix_fdopenw (struct pex_obj *, int, int);
static void pex_unix_cleanup (struct pex_obj *);
/* The list of functions we pass to the common routines. */
const struct pex_funcs funcs =
{
pex_unix_open_read,
pex_unix_open_write,
pex_unix_exec_child,
pex_unix_close,
pex_unix_wait,
pex_unix_pipe,
pex_unix_fdopenr,
pex_unix_fdopenw,
pex_unix_cleanup
};
/* Return a newly initialized pex_obj structure. */
struct pex_obj *
pex_init (int flags, const char *pname, const char *tempbase)
{
return pex_init_common (flags, pname, tempbase, &funcs);
}
/* Open a file for reading. */
static int
pex_unix_open_read (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name,
int binary ATTRIBUTE_UNUSED)
{
return open (name, O_RDONLY);
}
/* Open a file for writing. */
static int
pex_unix_open_write (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name,
int binary ATTRIBUTE_UNUSED, int append)
{
/* Note that we can't use O_EXCL here because gcc may have already
created the temporary file via make_temp_file. */
return open (name, O_WRONLY | O_CREAT
| (append ? O_APPEND : O_TRUNC), PUBLIC_MODE);
}
/* Close a file. */
static int
pex_unix_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd)
{
return close (fd);
}
/* Execute a child. */
#if defined(HAVE_SPAWNVE) && defined(HAVE_SPAWNVPE)
/* Implementation of pex->exec_child using the Cygwin spawn operation. */
/* Subroutine of pex_unix_exec_child. Move OLD_FD to a new file descriptor
to be stored in *PNEW_FD, save the flags in *PFLAGS, and arrange for the
saved copy to be close-on-exec. Move CHILD_FD into OLD_FD. If CHILD_FD
is -1, OLD_FD is to be closed. Return -1 on error. */
static int
save_and_install_fd(int *pnew_fd, int *pflags, int old_fd, int child_fd)
{
int new_fd, flags;
flags = fcntl (old_fd, F_GETFD);
/* If we could not retrieve the flags, then OLD_FD was not open. */
if (flags < 0)
{
new_fd = -1, flags = 0;
if (child_fd >= 0 && dup2 (child_fd, old_fd) < 0)
return -1;
}
/* If we wish to close OLD_FD, just mark it CLOEXEC. */
else if (child_fd == -1)
{
new_fd = old_fd;
if ((flags & FD_CLOEXEC) == 0 && fcntl (old_fd, F_SETFD, FD_CLOEXEC) < 0)
return -1;
}
/* Otherwise we need to save a copy of OLD_FD before installing CHILD_FD. */
else
{
#ifdef F_DUPFD_CLOEXEC
new_fd = fcntl (old_fd, F_DUPFD_CLOEXEC, 3);
if (new_fd < 0)
return -1;
#else
/* Prefer F_DUPFD over dup in order to avoid getting a new fd
in the range 0-2, right where a new stderr fd might get put. */
new_fd = fcntl (old_fd, F_DUPFD, 3);
if (new_fd < 0)
return -1;
if (fcntl (new_fd, F_SETFD, FD_CLOEXEC) < 0)
return -1;
#endif
if (dup2 (child_fd, old_fd) < 0)
return -1;
}
*pflags = flags;
if (pnew_fd)
*pnew_fd = new_fd;
else if (new_fd != old_fd)
abort ();
return 0;
}
/* Subroutine of pex_unix_exec_child. Move SAVE_FD back to OLD_FD
restoring FLAGS. If SAVE_FD < 0, OLD_FD is to be closed. */
static int
restore_fd(int old_fd, int save_fd, int flags)
{
/* For SAVE_FD < 0, all we have to do is restore the
"closed-ness" of the original. */
if (save_fd < 0)
return close (old_fd);
/* For SAVE_FD == OLD_FD, all we have to do is restore the
original setting of the CLOEXEC flag. */
if (save_fd == old_fd)
{
if (flags & FD_CLOEXEC)
return 0;
return fcntl (old_fd, F_SETFD, flags);
}
/* Otherwise we have to move the descriptor back, restore the flags,
and close the saved copy. */
#ifdef HAVE_DUP3
if (flags == FD_CLOEXEC)
{
if (dup3 (save_fd, old_fd, O_CLOEXEC) < 0)
return -1;
}
else
#endif
{
if (dup2 (save_fd, old_fd) < 0)
return -1;
if (flags != 0 && fcntl (old_fd, F_SETFD, flags) < 0)
return -1;
}
return close (save_fd);
}
static pid_t
pex_unix_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED,
int flags, const char *executable,
char * const * argv, char * const * env,
int in, int out, int errdes, int toclose,
const char **errmsg, int *err)
{
int fl_in = 0, fl_out = 0, fl_err = 0, fl_tc = 0;
int save_in = -1, save_out = -1, save_err = -1;
int max, retries;
pid_t pid;
if (flags & PEX_STDERR_TO_STDOUT)
errdes = out;
/* We need the three standard file descriptors to be set up as for
the child before we perform the spawn. The file descriptors for
the parent need to be moved and marked for close-on-exec. */
if (in != STDIN_FILE_NO
&& save_and_install_fd (&save_in, &fl_in, STDIN_FILE_NO, in) < 0)
goto error_dup2;
if (out != STDOUT_FILE_NO
&& save_and_install_fd (&save_out, &fl_out, STDOUT_FILE_NO, out) < 0)
goto error_dup2;
if (errdes != STDERR_FILE_NO
&& save_and_install_fd (&save_err, &fl_err, STDERR_FILE_NO, errdes) < 0)
goto error_dup2;
if (toclose >= 0
&& save_and_install_fd (NULL, &fl_tc, toclose, -1) < 0)
goto error_dup2;
/* Now that we've moved the file descriptors for the child into place,
close the originals. Be careful not to close any of the standard
file descriptors that we just set up. */
max = -1;
if (errdes >= 0)
max = STDERR_FILE_NO;
else if (out >= 0)
max = STDOUT_FILE_NO;
else if (in >= 0)
max = STDIN_FILE_NO;
if (in > max)
close (in);
if (out > max)
close (out);
if (errdes > max && errdes != out)
close (errdes);
/* If we were not given an environment, use the global environment. */
if (env == NULL)
env = environ;
/* Launch the program. If we get EAGAIN (normally out of pid's), try
again a few times with increasing backoff times. */
retries = 0;
while (1)
{
typedef const char * const *cc_cp;
if (flags & PEX_SEARCH)
pid = spawnvpe (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env);
else
pid = spawnve (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env);
if (pid > 0)
break;
*err = errno;
*errmsg = "spawn";
if (errno != EAGAIN || ++retries == 4)
return (pid_t) -1;
sleep (1 << retries);
}
/* Success. Restore the parent's file descriptors that we saved above. */
if (toclose >= 0
&& restore_fd (toclose, toclose, fl_tc) < 0)
goto error_dup2;
if (in != STDIN_FILE_NO
&& restore_fd (STDIN_FILE_NO, save_in, fl_in) < 0)
goto error_dup2;
if (out != STDOUT_FILE_NO
&& restore_fd (STDOUT_FILE_NO, save_out, fl_out) < 0)
goto error_dup2;
if (errdes != STDERR_FILE_NO
&& restore_fd (STDERR_FILE_NO, save_err, fl_err) < 0)
goto error_dup2;
return pid;
error_dup2:
*err = errno;
*errmsg = "dup2";
return (pid_t) -1;
}
#elif defined(HAVE_POSIX_SPAWN) && defined(HAVE_POSIX_SPAWNP)
/* Implementation of pex->exec_child using posix_spawn. */
static pid_t
pex_unix_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED,
int flags, const char *executable,
char * const * argv, char * const * env,
int in, int out, int errdes,
int toclose, const char **errmsg, int *err)
{
int ret;
pid_t pid = -1;
posix_spawnattr_t attr;
posix_spawn_file_actions_t actions;
int attr_initialized = 0, actions_initialized = 0;
*err = 0;
ret = posix_spawnattr_init (&attr);
if (ret)
{
*err = ret;
*errmsg = "posix_spawnattr_init";
goto exit;
}
attr_initialized = 1;
/* Use vfork() on glibc <=2.24. */
#ifdef POSIX_SPAWN_USEVFORK
ret = posix_spawnattr_setflags (&attr, POSIX_SPAWN_USEVFORK);
if (ret)
{
*err = ret;
*errmsg = "posix_spawnattr_setflags";
goto exit;
}
#endif
ret = posix_spawn_file_actions_init (&actions);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_init";
goto exit;
}
actions_initialized = 1;
if (in != STDIN_FILE_NO)
{
ret = posix_spawn_file_actions_adddup2 (&actions, in, STDIN_FILE_NO);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_adddup2";
goto exit;
}
ret = posix_spawn_file_actions_addclose (&actions, in);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_addclose";
goto exit;
}
}
if (out != STDOUT_FILE_NO)
{
ret = posix_spawn_file_actions_adddup2 (&actions, out, STDOUT_FILE_NO);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_adddup2";
goto exit;
}
ret = posix_spawn_file_actions_addclose (&actions, out);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_addclose";
goto exit;
}
}
if (errdes != STDERR_FILE_NO)
{
ret = posix_spawn_file_actions_adddup2 (&actions, errdes, STDERR_FILE_NO);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_adddup2";
goto exit;
}
ret = posix_spawn_file_actions_addclose (&actions, errdes);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_addclose";
goto exit;
}
}
if (toclose >= 0)
{
ret = posix_spawn_file_actions_addclose (&actions, toclose);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_addclose";
goto exit;
}
}
if ((flags & PEX_STDERR_TO_STDOUT) != 0)
{
ret = posix_spawn_file_actions_adddup2 (&actions, STDOUT_FILE_NO, STDERR_FILE_NO);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn_file_actions_adddup2";
goto exit;
}
}
if ((flags & PEX_SEARCH) != 0)
{
ret = posix_spawnp (&pid, executable, &actions, &attr, argv, env ? env : environ);
if (ret)
{
*err = ret;
*errmsg = "posix_spawnp";
goto exit;
}
}
else
{
ret = posix_spawn (&pid, executable, &actions, &attr, argv, env ? env : environ);
if (ret)
{
*err = ret;
*errmsg = "posix_spawn";
goto exit;
}
}
exit:
if (actions_initialized)
posix_spawn_file_actions_destroy (&actions);
if (attr_initialized)
posix_spawnattr_destroy (&attr);
if (!*err && in != STDIN_FILE_NO)
if (close (in))
*errmsg = "close", *err = errno, pid = -1;
if (!*err && out != STDOUT_FILE_NO)
if (close (out))
*errmsg = "close", *err = errno, pid = -1;
if (!*err && errdes != STDERR_FILE_NO)
if (close (errdes))
*errmsg = "close", *err = errno, pid = -1;
return pid;
}
#else
/* Implementation of pex->exec_child using standard vfork + exec. */
static pid_t
pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable,
char * const * argv, char * const * env,
int in, int out, int errdes,
int toclose, const char **errmsg, int *err)
{
pid_t pid = -1;
/* Tuple to communicate error from child to parent. We can safely
transfer string literal pointers as both run with identical
address mappings. */
struct fn_err
{
const char *fn;
int err;
};
volatile int do_pipe = 0;
volatile int pipes[2]; /* [0]:reader,[1]:writer. */
#ifdef O_CLOEXEC
do_pipe = 1;
#endif
if (do_pipe)
{
#ifdef HAVE_PIPE2
if (pipe2 ((int *)pipes, O_CLOEXEC))
do_pipe = 0;
#else
if (pipe ((int *)pipes))
do_pipe = 0;
else
{
if (fcntl (pipes[1], F_SETFD, FD_CLOEXEC) == -1)
{
close (pipes[0]);
close (pipes[1]);
do_pipe = 0;
}
}
#endif
}
/* We declare these to be volatile to avoid warnings from gcc about
them being clobbered by vfork. */
volatile int sleep_interval = 1;
volatile int retries;
/* We vfork and then set environ in the child before calling execvp.
This clobbers the parent's environ so we need to restore it.
It would be nice to use one of the exec* functions that takes an
environment as a parameter, but that may have portability
issues. It is marked volatile so the child doesn't consider it a
dead variable and therefore clobber where ever it is stored. */
char **volatile save_environ = environ;
for (retries = 0; retries < 4; ++retries)
{
pid = vfork ();
if (pid >= 0)
break;
sleep (sleep_interval);
sleep_interval *= 2;
}
switch (pid)
{
case -1:
if (do_pipe)
{
close (pipes[0]);
close (pipes[1]);
}
*err = errno;
*errmsg = VFORK_STRING;
return (pid_t) -1;
case 0:
/* Child process. */
{
struct fn_err failed;
failed.fn = NULL;
if (do_pipe)
close (pipes[0]);
if (!failed.fn && in != STDIN_FILE_NO)
{
if (dup2 (in, STDIN_FILE_NO) < 0)
failed.fn = "dup2", failed.err = errno;
else if (close (in) < 0)
failed.fn = "close", failed.err = errno;
}
if (!failed.fn && out != STDOUT_FILE_NO)
{
if (dup2 (out, STDOUT_FILE_NO) < 0)
failed.fn = "dup2", failed.err = errno;
else if (close (out) < 0)
failed.fn = "close", failed.err = errno;
}
if (!failed.fn && errdes != STDERR_FILE_NO)
{
if (dup2 (errdes, STDERR_FILE_NO) < 0)
failed.fn = "dup2", failed.err = errno;
else if (close (errdes) < 0)
failed.fn = "close", failed.err = errno;
}
if (!failed.fn && toclose >= 0)
{
if (close (toclose) < 0)
failed.fn = "close", failed.err = errno;
}
if (!failed.fn && (flags & PEX_STDERR_TO_STDOUT) != 0)
{
if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0)
failed.fn = "dup2", failed.err = errno;
}
if (!failed.fn)
{
if (env)
/* NOTE: In a standard vfork implementation this clobbers
the parent's copy of environ "too" (in reality there's
only one copy). This is ok as we restore it below. */
environ = (char**) env;
if ((flags & PEX_SEARCH) != 0)
{
execvp (executable, to_ptr32 (argv));
failed.fn = "execvp", failed.err = errno;
}
else
{
execv (executable, to_ptr32 (argv));
failed.fn = "execv", failed.err = errno;
}
}
/* Something failed, report an error. We don't use stdio
routines, because we might be here due to a vfork call. */
ssize_t retval = 0;
if (!do_pipe
|| write (pipes[1], &failed, sizeof (failed)) != sizeof (failed))
{
/* The parent will not see our scream above, so write to
stdout. */
#define writeerr(s) (retval |= write (STDERR_FILE_NO, s, strlen (s)))
writeerr (obj->pname);
writeerr (": error trying to exec '");
writeerr (executable);
writeerr ("': ");
writeerr (failed.fn);
writeerr (": ");
writeerr (xstrerror (failed.err));
writeerr ("\n");
#undef writeerr
}
/* Exit with -2 if the error output failed, too. */
_exit (retval < 0 ? -2 : -1);
}
/* NOTREACHED */
return (pid_t) -1;
default:
/* Parent process. */
{
/* Restore environ. Note that the parent either doesn't run
until the child execs/exits (standard vfork behaviour), or
if it does run then vfork is behaving more like fork. In
either case we needn't worry about clobbering the child's
copy of environ. */
environ = save_environ;
struct fn_err failed;
failed.fn = NULL;
if (do_pipe)
{
close (pipes[1]);
ssize_t len = read (pipes[0], &failed, sizeof (failed));
if (len < 0)
failed.fn = NULL;
close (pipes[0]);
}
if (!failed.fn && in != STDIN_FILE_NO)
if (close (in) < 0)
failed.fn = "close", failed.err = errno;
if (!failed.fn && out != STDOUT_FILE_NO)
if (close (out) < 0)
failed.fn = "close", failed.err = errno;
if (!failed.fn && errdes != STDERR_FILE_NO)
if (close (errdes) < 0)
failed.fn = "close", failed.err = errno;
if (failed.fn)
{
*err = failed.err;
*errmsg = failed.fn;
return (pid_t) -1;
}
}
return pid;
}
}
#endif /* SPAWN */
/* Wait for a child process to complete. */
static pid_t
pex_unix_wait (struct pex_obj *obj, pid_t pid, int *status,
struct pex_time *time, int done, const char **errmsg,
int *err)
{
/* If we are cleaning up when the caller didn't retrieve process
status for some reason, encourage the process to go away. */
if (done)
kill (pid, SIGTERM);
if (pex_wait (obj, pid, status, time) < 0)
{
*err = errno;
*errmsg = "wait";
return -1;
}
return 0;
}
/* Create a pipe. */
static int
pex_unix_pipe (struct pex_obj *obj ATTRIBUTE_UNUSED, int *p,
int binary ATTRIBUTE_UNUSED)
{
return pipe (p);
}
/* Get a FILE pointer to read from a file descriptor. */
static FILE *
pex_unix_fdopenr (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd,
int binary ATTRIBUTE_UNUSED)
{
return fdopen (fd, "r");
}
static FILE *
pex_unix_fdopenw (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd,
int binary ATTRIBUTE_UNUSED)
{
if (fcntl (fd, F_SETFD, FD_CLOEXEC) < 0)
return NULL;
return fdopen (fd, "w");
}
static void
pex_unix_cleanup (struct pex_obj *obj ATTRIBUTE_UNUSED)
{
#if !defined (HAVE_WAIT4) && !defined (HAVE_WAITPID)
while (obj->sysdep != NULL)
{
struct status_list *this;
struct status_list *next;
this = (struct status_list *) obj->sysdep;
next = this->next;
free (this);
obj->sysdep = (void *) next;
}
#endif
}