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authorMarc Espie <espie@cvs.openbsd.org>2003-12-28 20:11:51 +0000
committerMarc Espie <espie@cvs.openbsd.org>2003-12-28 20:11:51 +0000
commit9d673bf4b0565979006360485b48e15dc2aa81af (patch)
tree7cb4008c0f6d6870d1214a7ae4c5b69007d7081f /gnu/lib
parentf75db548a29591de5bebc83b27a6aa703451fcc1 (diff)
resurrect pexecute.c for now, since vax and m68k barf on pex-unix.c
Diffstat (limited to 'gnu/lib')
-rw-r--r--gnu/lib/libiberty/Makefile.bsd-wrapper4
-rw-r--r--gnu/lib/libiberty/src/pexecute.c792
2 files changed, 794 insertions, 2 deletions
diff --git a/gnu/lib/libiberty/Makefile.bsd-wrapper b/gnu/lib/libiberty/Makefile.bsd-wrapper
index 81b526c89f6..7a60990f9c6 100644
--- a/gnu/lib/libiberty/Makefile.bsd-wrapper
+++ b/gnu/lib/libiberty/Makefile.bsd-wrapper
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile.bsd-wrapper,v 1.5 2003/12/26 04:14:45 brad Exp $
+# $OpenBSD: Makefile.bsd-wrapper,v 1.6 2003/12/28 20:11:50 espie Exp $
LIB= iberty
CPPFLAGS+= -DHAVE_CONFIG_H -I$(.CURDIR) -I$(.CURDIR)/include -I$(.OBJDIR)
@@ -13,7 +13,7 @@ SRCS= argv.c choose-temp.c concat.c cplus-dem.c cp-demangle.c \
hashtab.c hex.c fibheap.c partition.c \
floatformat.c make-temp-file.c make-relative-prefix.c \
objalloc.c obstack.c oldhashtab.c \
- pex-unix.c safe-ctype.c spaces.c splay-tree.c \
+ pexecute.c safe-ctype.c spaces.c splay-tree.c \
strerror.c strsignal.c \
xatexit.c xexit.c xmalloc.c xmemdup xstrerror.c xstrdup.c \
physmem.c lbasename.c lrealpath.c \
diff --git a/gnu/lib/libiberty/src/pexecute.c b/gnu/lib/libiberty/src/pexecute.c
new file mode 100644
index 00000000000..347c4db1092
--- /dev/null
+++ b/gnu/lib/libiberty/src/pexecute.c
@@ -0,0 +1,792 @@
+/* Utilities to execute a program in a subprocess (possibly linked by pipes
+ with other subprocesses), and wait for it.
+ Copyright (C) 1996-2000 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., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
+
+/* This file exports two functions: pexecute and pwait. */
+
+/* This file lives in at least two places: libiberty and gcc.
+ Don't change one without the other. */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include <errno.h>
+#ifdef NEED_DECLARATION_ERRNO
+extern int errno;
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+
+#include "libiberty.h"
+#include "safe-ctype.h"
+
+/* stdin file number. */
+#define STDIN_FILE_NO 0
+
+/* stdout file number. */
+#define STDOUT_FILE_NO 1
+
+/* value of `pipe': port index for reading. */
+#define READ_PORT 0
+
+/* value of `pipe': port index for writing. */
+#define WRITE_PORT 1
+
+static char *install_error_msg = "installation problem, cannot exec `%s'";
+
+/* pexecute: execute a program.
+
+@deftypefn Extension int pexecute (const char *@var{program}, char * const *@var{argv}, const char *@var{this_pname}, const char *@var{temp_base}, char **@var{errmsg_fmt}, char **@var{errmsg_arg}, int flags)
+
+Executes a program.
+
+@var{program} and @var{argv} are the arguments to
+@code{execv}/@code{execvp}.
+
+@var{this_pname} is name of the calling program (i.e., @code{argv[0]}).
+
+@var{temp_base} is the path name, sans suffix, of a temporary file to
+use if needed. This is currently only needed for MS-DOS ports that
+don't use @code{go32} (do any still exist?). Ports that don't need it
+can pass @code{NULL}.
+
+(@code{@var{flags} & PEXECUTE_SEARCH}) is non-zero if @env{PATH} should be searched
+(??? It's not clear that GCC passes this flag correctly). (@code{@var{flags} &
+PEXECUTE_FIRST}) is nonzero for the first process in chain.
+(@code{@var{flags} & PEXECUTE_FIRST}) is nonzero for the last process
+in chain. The first/last flags could be simplified to only mark the
+last of a chain of processes but that requires the caller to always
+mark the last one (and not give up early if some error occurs).
+It's more robust to require the caller to mark both ends of the chain.
+
+The result is the pid on systems like Unix where we
+@code{fork}/@code{exec} and on systems like WIN32 and OS/2 where we
+use @code{spawn}. It is up to the caller to wait for the child.
+
+The result is the @code{WEXITSTATUS} on systems like MS-DOS where we
+@code{spawn} and wait for the child here.
+
+Upon failure, @var{errmsg_fmt} and @var{errmsg_arg} are set to the
+text of the error message with an optional argument (if not needed,
+@var{errmsg_arg} is set to @code{NULL}), and @minus{}1 is returned.
+@code{errno} is available to the caller to use.
+
+@end deftypefn
+
+@deftypefn Extension int pwait (int @var{pid}, int *@var{status}, int @var{flags})
+
+Waits for a program started by @code{pexecute} to finish.
+
+@var{pid} is the process id of the task to wait for. @var{status} is
+the `status' argument to wait. @var{flags} is currently unused (allows
+future enhancement without breaking upward compatibility). Pass 0 for now.
+
+The result is the pid of the child reaped, or -1 for failure
+(@code{errno} says why).
+
+On systems that don't support waiting for a particular child, @var{pid} is
+ignored. On systems like MS-DOS that don't really multitask @code{pwait}
+is just a mechanism to provide a consistent interface for the caller.
+
+@end deftypefn
+
+@undocumented pfinish
+
+ pfinish: finish generation of script
+
+ pfinish is necessary for systems like MPW where a script is generated that
+ runs the requested programs. */
+
+#ifdef __MSDOS__
+
+/* MSDOS doesn't multitask, but for the sake of a consistent interface
+ the code behaves like it does. pexecute runs the program, tucks the
+ exit code away, and returns a "pid". pwait must be called to fetch the
+ exit code. */
+
+#include <process.h>
+
+/* For communicating information from pexecute to pwait. */
+static int last_pid = 0;
+static int last_status = 0;
+static int last_reaped = 0;
+
+int
+pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags)
+ const char *program;
+ char * const *argv;
+ const char *this_pname;
+ const char *temp_base;
+ char **errmsg_fmt, **errmsg_arg;
+ int flags;
+{
+ int rc;
+
+ last_pid++;
+ if (last_pid < 0)
+ last_pid = 1;
+
+ if ((flags & PEXECUTE_ONE) != PEXECUTE_ONE)
+ abort ();
+
+#ifdef __DJGPP__
+ /* ??? What are the possible return values from spawnv? */
+ rc = (flags & PEXECUTE_SEARCH ? spawnvp : spawnv) (P_WAIT, program, argv);
+#else
+ char *scmd, *rf;
+ FILE *argfile;
+ int i, el = flags & PEXECUTE_SEARCH ? 4 : 0;
+
+ if (temp_base == 0)
+ temp_base = choose_temp_base ();
+ scmd = (char *) xmalloc (strlen (program) + strlen (temp_base) + 6 + el);
+ rf = scmd + strlen(program) + 2 + el;
+ sprintf (scmd, "%s%s @%s.gp", program,
+ (flags & PEXECUTE_SEARCH ? ".exe" : ""), temp_base);
+ argfile = fopen (rf, "w");
+ if (argfile == 0)
+ {
+ int errno_save = errno;
+ free (scmd);
+ errno = errno_save;
+ *errmsg_fmt = "cannot open `%s.gp'";
+ *errmsg_arg = temp_base;
+ return -1;
+ }
+
+ for (i=1; argv[i]; i++)
+ {
+ char *cp;
+ for (cp = argv[i]; *cp; cp++)
+ {
+ if (*cp == '"' || *cp == '\'' || *cp == '\\' || ISSPACE (*cp))
+ fputc ('\\', argfile);
+ fputc (*cp, argfile);
+ }
+ fputc ('\n', argfile);
+ }
+ fclose (argfile);
+
+ rc = system (scmd);
+
+ {
+ int errno_save = errno;
+ remove (rf);
+ free (scmd);
+ errno = errno_save;
+ }
+#endif
+
+ if (rc == -1)
+ {
+ *errmsg_fmt = install_error_msg;
+ *errmsg_arg = (char *)program;
+ return -1;
+ }
+
+ /* Tuck the status away for pwait, and return a "pid". */
+ last_status = rc << 8;
+ return last_pid;
+}
+
+/* Use ECHILD if available, otherwise use EINVAL. */
+#ifdef ECHILD
+#define PWAIT_ERROR ECHILD
+#else
+#define PWAIT_ERROR EINVAL
+#endif
+
+int
+pwait (pid, status, flags)
+ int pid;
+ int *status;
+ int flags;
+{
+ /* On MSDOS each pexecute must be followed by it's associated pwait. */
+ if (pid != last_pid
+ /* Called twice for the same child? */
+ || pid == last_reaped)
+ {
+ errno = PWAIT_ERROR;
+ return -1;
+ }
+ /* ??? Here's an opportunity to canonicalize the values in STATUS.
+ Needed? */
+#ifdef __DJGPP__
+ *status = (last_status >> 8);
+#else
+ *status = last_status;
+#endif
+ last_reaped = last_pid;
+ return last_pid;
+}
+
+#endif /* MSDOS */
+
+#if defined (_WIN32) && ! defined (_UWIN)
+
+#include <process.h>
+
+#ifdef __CYGWIN__
+
+#define fix_argv(argvec) (argvec)
+
+extern int _spawnv ();
+extern int _spawnvp ();
+
+#else /* ! __CYGWIN__ */
+
+/* This is a kludge to get around the Microsoft C spawn functions' propensity
+ to remove the outermost set of double quotes from all arguments. */
+
+static const char * const *
+fix_argv (argvec)
+ char **argvec;
+{
+ int i;
+
+ for (i = 1; argvec[i] != 0; i++)
+ {
+ int len, j;
+ char *temp, *newtemp;
+
+ temp = argvec[i];
+ len = strlen (temp);
+ for (j = 0; j < len; j++)
+ {
+ if (temp[j] == '"')
+ {
+ newtemp = xmalloc (len + 2);
+ strncpy (newtemp, temp, j);
+ newtemp [j] = '\\';
+ strncpy (&newtemp [j+1], &temp [j], len-j);
+ newtemp [len+1] = 0;
+ temp = newtemp;
+ len++;
+ j++;
+ }
+ }
+
+ argvec[i] = temp;
+ }
+
+ for (i = 0; argvec[i] != 0; i++)
+ {
+ if (strpbrk (argvec[i], " \t"))
+ {
+ int len, trailing_backslash;
+ char *temp;
+
+ len = strlen (argvec[i]);
+ trailing_backslash = 0;
+
+ /* There is an added complication when an arg with embedded white
+ space ends in a backslash (such as in the case of -iprefix arg
+ passed to cpp). The resulting quoted strings gets misinterpreted
+ by the command interpreter -- it thinks that the ending quote
+ is escaped by the trailing backslash and things get confused.
+ We handle this case by escaping the trailing backslash, provided
+ it was not escaped in the first place. */
+ if (len > 1
+ && argvec[i][len-1] == '\\'
+ && argvec[i][len-2] != '\\')
+ {
+ trailing_backslash = 1;
+ ++len; /* to escape the final backslash. */
+ }
+
+ len += 2; /* and for the enclosing quotes. */
+
+ temp = xmalloc (len + 1);
+ temp[0] = '"';
+ strcpy (temp + 1, argvec[i]);
+ if (trailing_backslash)
+ temp[len-2] = '\\';
+ temp[len-1] = '"';
+ temp[len] = '\0';
+
+ argvec[i] = temp;
+ }
+ }
+
+ return (const char * const *) argvec;
+}
+#endif /* __CYGWIN__ */
+
+#include <io.h>
+#include <fcntl.h>
+#include <signal.h>
+
+/* mingw32 headers may not define the following. */
+
+#ifndef _P_WAIT
+# define _P_WAIT 0
+# define _P_NOWAIT 1
+# define _P_OVERLAY 2
+# define _P_NOWAITO 3
+# define _P_DETACH 4
+
+# define WAIT_CHILD 0
+# define WAIT_GRANDCHILD 1
+#endif
+
+/* Win32 supports pipes */
+int
+pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags)
+ const char *program;
+ char * const *argv;
+ const char *this_pname;
+ const char *temp_base;
+ char **errmsg_fmt, **errmsg_arg;
+ int flags;
+{
+ int pid;
+ int pdes[2], org_stdin, org_stdout;
+ int input_desc, output_desc;
+ int retries, sleep_interval;
+
+ /* Pipe waiting from last process, to be used as input for the next one.
+ Value is STDIN_FILE_NO if no pipe is waiting
+ (i.e. the next command is the first of a group). */
+ static int last_pipe_input;
+
+ /* If this is the first process, initialize. */
+ if (flags & PEXECUTE_FIRST)
+ last_pipe_input = STDIN_FILE_NO;
+
+ input_desc = last_pipe_input;
+
+ /* If this isn't the last process, make a pipe for its output,
+ and record it as waiting to be the input to the next process. */
+ if (! (flags & PEXECUTE_LAST))
+ {
+ if (_pipe (pdes, 256, O_BINARY) < 0)
+ {
+ *errmsg_fmt = "pipe";
+ *errmsg_arg = NULL;
+ return -1;
+ }
+ output_desc = pdes[WRITE_PORT];
+ last_pipe_input = pdes[READ_PORT];
+ }
+ else
+ {
+ /* Last process. */
+ output_desc = STDOUT_FILE_NO;
+ last_pipe_input = STDIN_FILE_NO;
+ }
+
+ if (input_desc != STDIN_FILE_NO)
+ {
+ org_stdin = dup (STDIN_FILE_NO);
+ dup2 (input_desc, STDIN_FILE_NO);
+ close (input_desc);
+ }
+
+ if (output_desc != STDOUT_FILE_NO)
+ {
+ org_stdout = dup (STDOUT_FILE_NO);
+ dup2 (output_desc, STDOUT_FILE_NO);
+ close (output_desc);
+ }
+
+ pid = (flags & PEXECUTE_SEARCH ? _spawnvp : _spawnv)
+ (_P_NOWAIT, program, fix_argv(argv));
+
+ if (input_desc != STDIN_FILE_NO)
+ {
+ dup2 (org_stdin, STDIN_FILE_NO);
+ close (org_stdin);
+ }
+
+ if (output_desc != STDOUT_FILE_NO)
+ {
+ dup2 (org_stdout, STDOUT_FILE_NO);
+ close (org_stdout);
+ }
+
+ if (pid == -1)
+ {
+ *errmsg_fmt = install_error_msg;
+ *errmsg_arg = program;
+ return -1;
+ }
+
+ return pid;
+}
+
+/* MS CRTDLL doesn't return enough information in status to decide if the
+ child exited due to a signal or not, rather it simply returns an
+ integer with the exit code of the child; eg., if the child exited with
+ an abort() call and didn't have a handler for SIGABRT, it simply returns
+ with status = 3. We fix the status code to conform to the usual WIF*
+ macros. Note that WIFSIGNALED will never be true under CRTDLL. */
+
+int
+pwait (pid, status, flags)
+ int pid;
+ int *status;
+ int flags;
+{
+#ifdef __CYGWIN__
+ return wait (status);
+#else
+ int termstat;
+
+ pid = _cwait (&termstat, pid, WAIT_CHILD);
+
+ /* ??? Here's an opportunity to canonicalize the values in STATUS.
+ Needed? */
+
+ /* cwait returns the child process exit code in termstat.
+ A value of 3 indicates that the child caught a signal, but not
+ which one. Since only SIGABRT, SIGFPE and SIGINT do anything, we
+ report SIGABRT. */
+ if (termstat == 3)
+ *status = SIGABRT;
+ else
+ *status = (((termstat) & 0xff) << 8);
+
+ return pid;
+#endif /* __CYGWIN__ */
+}
+
+#endif /* _WIN32 && ! _UWIN */
+
+#ifdef OS2
+
+/* ??? Does OS2 have process.h? */
+extern int spawnv ();
+extern int spawnvp ();
+
+int
+pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags)
+ const char *program;
+ char * const *argv;
+ const char *this_pname;
+ const char *temp_base;
+ char **errmsg_fmt, **errmsg_arg;
+ int flags;
+{
+ int pid;
+
+ if ((flags & PEXECUTE_ONE) != PEXECUTE_ONE)
+ abort ();
+ /* ??? Presumably 1 == _P_NOWAIT. */
+ pid = (flags & PEXECUTE_SEARCH ? spawnvp : spawnv) (1, program, argv);
+ if (pid == -1)
+ {
+ *errmsg_fmt = install_error_msg;
+ *errmsg_arg = program;
+ return -1;
+ }
+ return pid;
+}
+
+int
+pwait (pid, status, flags)
+ int pid;
+ int *status;
+ int flags;
+{
+ /* ??? Here's an opportunity to canonicalize the values in STATUS.
+ Needed? */
+ int pid = wait (status);
+ return pid;
+}
+
+#endif /* OS2 */
+
+#ifdef MPW
+
+/* MPW pexecute doesn't actually run anything; instead, it writes out
+ script commands that, when run, will do the actual executing.
+
+ For example, in GCC's case, GCC will write out several script commands:
+
+ cpp ...
+ cc1 ...
+ as ...
+ ld ...
+
+ and then exit. None of the above programs will have run yet. The task
+ that called GCC will then execute the script and cause cpp,etc. to run.
+ The caller must invoke pfinish before calling exit. This adds
+ the finishing touches to the generated script. */
+
+static int first_time = 1;
+
+int
+pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags)
+ const char *program;
+ char * const *argv;
+ const char *this_pname;
+ const char *temp_base;
+ char **errmsg_fmt, **errmsg_arg;
+ int flags;
+{
+ char tmpprogram[255];
+ char *cp, *tmpname;
+ int i;
+
+ mpwify_filename (program, tmpprogram);
+ if (first_time)
+ {
+ printf ("Set Failed 0\n");
+ first_time = 0;
+ }
+
+ fputs ("If {Failed} == 0\n", stdout);
+ /* If being verbose, output a copy of the command. It should be
+ accurate enough and escaped enough to be "clickable". */
+ if (flags & PEXECUTE_VERBOSE)
+ {
+ fputs ("\tEcho ", stdout);
+ fputc ('\'', stdout);
+ fputs (tmpprogram, stdout);
+ fputc ('\'', stdout);
+ fputc (' ', stdout);
+ for (i=1; argv[i]; i++)
+ {
+ fputc ('\'', stdout);
+ /* See if we have an argument that needs fixing. */
+ if (strchr(argv[i], '/'))
+ {
+ tmpname = (char *) xmalloc (256);
+ mpwify_filename (argv[i], tmpname);
+ argv[i] = tmpname;
+ }
+ for (cp = argv[i]; *cp; cp++)
+ {
+ /* Write an Option-d escape char in front of special chars. */
+ if (strchr("'+", *cp))
+ fputc ('\266', stdout);
+ fputc (*cp, stdout);
+ }
+ fputc ('\'', stdout);
+ fputc (' ', stdout);
+ }
+ fputs ("\n", stdout);
+ }
+ fputs ("\t", stdout);
+ fputs (tmpprogram, stdout);
+ fputc (' ', stdout);
+
+ for (i=1; argv[i]; i++)
+ {
+ /* See if we have an argument that needs fixing. */
+ if (strchr(argv[i], '/'))
+ {
+ tmpname = (char *) xmalloc (256);
+ mpwify_filename (argv[i], tmpname);
+ argv[i] = tmpname;
+ }
+ if (strchr (argv[i], ' '))
+ fputc ('\'', stdout);
+ for (cp = argv[i]; *cp; cp++)
+ {
+ /* Write an Option-d escape char in front of special chars. */
+ if (strchr("'+", *cp))
+ fputc ('\266', stdout);
+ fputc (*cp, stdout);
+ }
+ if (strchr (argv[i], ' '))
+ fputc ('\'', stdout);
+ fputc (' ', stdout);
+ }
+
+ fputs ("\n", stdout);
+
+ /* Output commands that arrange to clean up and exit if a failure occurs.
+ We have to be careful to collect the status from the program that was
+ run, rather than some other script command. Also, we don't exit
+ immediately, since necessary cleanups are at the end of the script. */
+ fputs ("\tSet TmpStatus {Status}\n", stdout);
+ fputs ("\tIf {TmpStatus} != 0\n", stdout);
+ fputs ("\t\tSet Failed {TmpStatus}\n", stdout);
+ fputs ("\tEnd\n", stdout);
+ fputs ("End\n", stdout);
+
+ /* We're just composing a script, can't fail here. */
+ return 0;
+}
+
+int
+pwait (pid, status, flags)
+ int pid;
+ int *status;
+ int flags;
+{
+ *status = 0;
+ return 0;
+}
+
+/* Write out commands that will exit with the correct error code
+ if something in the script failed. */
+
+void
+pfinish ()
+{
+ printf ("\tExit \"{Failed}\"\n");
+}
+
+#endif /* MPW */
+
+/* include for Unix-like environments but not for Dos-like environments */
+#if ! defined (__MSDOS__) && ! defined (OS2) && ! defined (MPW) \
+ && ! (defined (_WIN32) && ! defined (_UWIN))
+
+extern int execv ();
+extern int execvp ();
+
+int
+pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags)
+ const char *program;
+ char * const *argv;
+ const char *this_pname;
+ const char *temp_base ATTRIBUTE_UNUSED;
+ char **errmsg_fmt, **errmsg_arg;
+ int flags;
+{
+ int (*func)() = (flags & PEXECUTE_SEARCH ? execvp : execv);
+ int pid;
+ int pdes[2];
+ int input_desc, output_desc;
+ int retries, sleep_interval;
+ /* Pipe waiting from last process, to be used as input for the next one.
+ Value is STDIN_FILE_NO if no pipe is waiting
+ (i.e. the next command is the first of a group). */
+ static int last_pipe_input;
+
+ /* If this is the first process, initialize. */
+ if (flags & PEXECUTE_FIRST)
+ last_pipe_input = STDIN_FILE_NO;
+
+ input_desc = last_pipe_input;
+
+ /* If this isn't the last process, make a pipe for its output,
+ and record it as waiting to be the input to the next process. */
+ if (! (flags & PEXECUTE_LAST))
+ {
+ if (pipe (pdes) < 0)
+ {
+ *errmsg_fmt = "pipe";
+ *errmsg_arg = NULL;
+ return -1;
+ }
+ output_desc = pdes[WRITE_PORT];
+ last_pipe_input = pdes[READ_PORT];
+ }
+ else
+ {
+ /* Last process. */
+ output_desc = STDOUT_FILE_NO;
+ last_pipe_input = STDIN_FILE_NO;
+ }
+
+ /* Fork a subprocess; wait and retry if it fails. */
+ sleep_interval = 1;
+ pid = -1;
+ for (retries = 0; retries < 4; retries++)
+ {
+ pid = fork ();
+ if (pid >= 0)
+ break;
+ sleep (sleep_interval);
+ sleep_interval *= 2;
+ }
+
+ switch (pid)
+ {
+ case -1:
+ *errmsg_fmt = "fork";
+ *errmsg_arg = NULL;
+ return -1;
+
+ case 0: /* child */
+ /* Move the input and output pipes into place, if necessary. */
+ if (input_desc != STDIN_FILE_NO)
+ {
+ close (STDIN_FILE_NO);
+ dup (input_desc);
+ close (input_desc);
+ }
+ if (output_desc != STDOUT_FILE_NO)
+ {
+ close (STDOUT_FILE_NO);
+ dup (output_desc);
+ close (output_desc);
+ }
+
+ /* Close the parent's descs that aren't wanted here. */
+ if (last_pipe_input != STDIN_FILE_NO)
+ close (last_pipe_input);
+
+ /* Exec the program. */
+ (*func) (program, argv);
+
+ fprintf (stderr, "%s: ", this_pname);
+ fprintf (stderr, install_error_msg, program);
+ fprintf (stderr, ": %s\n", xstrerror (errno));
+ exit (-1);
+ /* NOTREACHED */
+ return 0;
+
+ default:
+ /* In the parent, after forking.
+ Close the descriptors that we made for this child. */
+ if (input_desc != STDIN_FILE_NO)
+ close (input_desc);
+ if (output_desc != STDOUT_FILE_NO)
+ close (output_desc);
+
+ /* Return child's process number. */
+ return pid;
+ }
+}
+
+int
+pwait (pid, status, flags)
+ int pid;
+ int *status;
+ int flags ATTRIBUTE_UNUSED;
+{
+ /* ??? Here's an opportunity to canonicalize the values in STATUS.
+ Needed? */
+#ifdef VMS
+ pid = waitpid (-1, status, 0);
+#else
+ pid = wait (status);
+#endif
+ return pid;
+}
+
+#endif /* ! __MSDOS__ && ! OS2 && ! MPW && ! (_WIN32 && ! _UWIN) */