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Diffstat (limited to 'linkers/libiberty/pex-unix.c')
| -rw-r--r-- | linkers/libiberty/pex-unix.c | 788 |
1 files changed, 788 insertions, 0 deletions
diff --git a/linkers/libiberty/pex-unix.c b/linkers/libiberty/pex-unix.c new file mode 100644 index 0000000..80a4770 --- /dev/null +++ b/linkers/libiberty/pex-unix.c @@ -0,0 +1,788 @@ +/* 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, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2009, + 2010 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 <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 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; + + for (argc=0; ptr64[argc]; argc++); + + /* Reallocate argv with 32 bit pointers. */ + short_argv = (__char_ptr_char_ptr32) decc$malloc + (sizeof (__char_ptr32) * (argc + 1)); + + for (argc=0; ptr64[argc]; argc++) + short_argv[argc] = (__char_ptr32) decc$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 ((int) 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 ((int) 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 void pex_child_error (struct pex_obj *, const char *, const char *, int) + ATTRIBUTE_NORETURN; +static int pex_unix_open_read (struct pex_obj *, const char *, int); +static int pex_unix_open_write (struct pex_obj *, const char *, 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 int 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) +{ + /* 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 | O_TRUNC, PUBLIC_MODE); +} + +/* Close a file. */ + +static int +pex_unix_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd) +{ + return close (fd); +} + +/* Report an error from a child process. We don't use stdio routines, + because we might be here due to a vfork call. */ + +static void +pex_child_error (struct pex_obj *obj, const char *executable, + const char *errmsg, int err) +{ + int retval = 0; +#define writeerr(s) retval |= (write (STDERR_FILE_NO, s, strlen (s)) < 0) + writeerr (obj->pname); + writeerr (": error trying to exec '"); + writeerr (executable); + writeerr ("': "); + writeerr (errmsg); + writeerr (": "); + writeerr (xstrerror (err)); + writeerr ("\n"); +#undef writeerr + /* Exit with -2 if the error output failed, too. */ + _exit (retval == 0 ? -1 : -2); +} + +/* Execute a child. */ + +extern char **environ; + +#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; +} + +#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; + + /* We declare these to be volatile to avoid warnings from gcc about + them being clobbered by vfork. */ + volatile int sleep_interval; + 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. */ + char **save_environ = environ; + + sleep_interval = 1; + pid = -1; + for (retries = 0; retries < 4; ++retries) + { + pid = vfork (); + if (pid >= 0) + break; + sleep (sleep_interval); + sleep_interval *= 2; + } + + switch (pid) + { + case -1: + *err = errno; + *errmsg = VFORK_STRING; + return (pid_t) -1; + + case 0: + /* Child process. */ + if (in != STDIN_FILE_NO) + { + if (dup2 (in, STDIN_FILE_NO) < 0) + pex_child_error (obj, executable, "dup2", errno); + if (close (in) < 0) + pex_child_error (obj, executable, "close", errno); + } + if (out != STDOUT_FILE_NO) + { + if (dup2 (out, STDOUT_FILE_NO) < 0) + pex_child_error (obj, executable, "dup2", errno); + if (close (out) < 0) + pex_child_error (obj, executable, "close", errno); + } + if (errdes != STDERR_FILE_NO) + { + if (dup2 (errdes, STDERR_FILE_NO) < 0) + pex_child_error (obj, executable, "dup2", errno); + if (close (errdes) < 0) + pex_child_error (obj, executable, "close", errno); + } + if (toclose >= 0) + { + if (close (toclose) < 0) + pex_child_error (obj, executable, "close", errno); + } + if ((flags & PEX_STDERR_TO_STDOUT) != 0) + { + if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0) + pex_child_error (obj, executable, "dup2", errno); + } + + 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)); + pex_child_error (obj, executable, "execvp", errno); + } + else + { + execv (executable, to_ptr32 (argv)); + pex_child_error (obj, executable, "execv", errno); + } + + /* 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; + + if (in != STDIN_FILE_NO) + { + if (close (in) < 0) + { + *err = errno; + *errmsg = "close"; + return (pid_t) -1; + } + } + if (out != STDOUT_FILE_NO) + { + if (close (out) < 0) + { + *err = errno; + *errmsg = "close"; + return (pid_t) -1; + } + } + if (errdes != STDERR_FILE_NO) + { + if (close (errdes) < 0) + { + *err = errno; + *errmsg = "close"; + return (pid_t) -1; + } + } + + return pid; + } +} +#endif /* SPAWN */ + +/* Wait for a child process to complete. */ + +static int +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 +} |