Imported Upstream version 93u+upstream

1 files changed, 296 insertions, 0 deletions

diff --git a/src/lib/libast/comp/spawnveg.c b/src/lib/libast/comp/spawnveg.c
new file mode 100644
index 0000000..6117e3a
--- /dev/null
+++ b/src/lib/libast/comp/spawnveg.c
@@ -0,0 +1,296 @@
+/***********************************************************************
+*                                                                      *
+*               This software is part of the ast package               *
+*          Copyright (c) 1985-2012 AT&T Intellectual Property          *
+*                      and is licensed under the                       *
+*                 Eclipse Public License, Version 1.0                  *
+*                    by AT&T Intellectual Property                     *
+*                                                                      *
+*                A copy of the License is available at                 *
+*          http://www.eclipse.org/org/documents/epl-v10.html           *
+*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
+*                                                                      *
+*              Information and Software Systems Research               *
+*                            AT&T Research                             *
+*                           Florham Park NJ                            *
+*                                                                      *
+*                 Glenn Fowler <gsf@research.att.com>                  *
+*                  David Korn <dgk@research.att.com>                   *
+*                   Phong Vo <kpv@research.att.com>                    *
+*                                                                      *
+***********************************************************************/
+#pragma prototyped
+
+/*
+ * spawnveg -- spawnve with process group or session control
+ *
+ *	pgid	<0	setsid()	[session group leader]
+ *		 0	nothing		[retain session and process group]
+ *		 1	setpgid(0,0)	[process group leader]
+ *		>1	setpgid(0,pgid)	[join process group]
+ */
+
+#include <ast.h>
+
+#if _lib_spawnveg
+
+NoN(spawnveg)
+
+#else
+
+#if _lib_posix_spawn > 1	/* reports underlying exec() errors */
+
+#include <spawn.h>
+#include <error.h>
+#include <wait.h>
+
+pid_t
+spawnveg(const char* path, char* const argv[], char* const envv[], pid_t pgid)
+{
+	int			err;
+	pid_t			pid;
+	posix_spawnattr_t	attr;
+
+	if (err = posix_spawnattr_init(&attr))
+		goto nope;
+	if (pgid)
+	{
+		if (pgid <= 1)
+			pgid = 0;
+		if (err = posix_spawnattr_setpgroup(&attr, pgid))
+			goto bad;
+		if (err = posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETPGROUP))
+			goto bad;
+	}
+	if (err = posix_spawn(&pid, path, NiL, &attr, argv, envv ? envv : environ))
+		goto bad;
+	posix_spawnattr_destroy(&attr);
+#if _lib_posix_spawn < 2
+	if (waitpid(pid, &err, WNOHANG|WNOWAIT) == pid && EXIT_STATUS(err) == 127)
+	{
+		while (waitpid(pid, NiL, 0) == -1 && errno == EINTR);
+		if (!access(path, X_OK))
+			errno = ENOEXEC;
+		pid = -1;
+	}
+#endif
+	return pid;
+ bad:
+	posix_spawnattr_destroy(&attr);
+ nope:
+	errno = err;
+	return -1;
+}
+
+#else
+
+#if _lib_spawn_mode
+
+#include <process.h>
+
+#ifndef P_NOWAIT
+#define P_NOWAIT	_P_NOWAIT
+#endif
+#ifndef P_DETACH
+#define P_DETACH	_P_DETACH
+#endif
+
+pid_t
+spawnveg(const char* path, char* const argv[], char* const envv[], pid_t pgid)
+{
+	return spawnve(pgid ? P_DETACH : P_NOWAIT, path, argv, envv ? envv : environ);
+}
+
+#else
+
+#if _lib_spawn && _hdr_spawn && _mem_pgroup_inheritance
+
+#include <spawn.h>
+
+/*
+ * open-edition/mvs/zos fork+exec+(setpgid)
+ */
+
+pid_t
+spawnveg(const char* path, char* const argv[], char* const envv[], pid_t pgid)
+{
+	struct inheritance	inherit;
+
+	inherit.flags = 0;
+	if (pgid)
+	{
+		inherit.flags |= SPAWN_SETGROUP;
+		inherit.pgroup = (pgid > 1) ? pgid : SPAWN_NEWPGROUP;
+	}
+	return spawn(path, 0, (int*)0, &inherit, (const char**)argv, (const char**)envv);
+}
+
+#else
+
+#include <error.h>
+#include <wait.h>
+#include <sig.h>
+#include <ast_tty.h>
+#include <ast_vfork.h>
+
+#ifndef ENOSYS
+#define ENOSYS	EINVAL
+#endif
+
+#if _lib_spawnve && _hdr_process
+#include <process.h>
+#if defined(P_NOWAIT) || defined(_P_NOWAIT)
+#undef	_lib_spawnve
+#endif
+#endif
+
+#if !_lib_vfork
+#undef	_real_vfork
+#endif
+
+/*
+ * fork+exec+(setsid|setpgid)
+ */
+
+pid_t
+spawnveg(const char* path, char* const argv[], char* const envv[], pid_t pgid)
+{
+#if _lib_fork || _lib_vfork
+	int			n;
+	int			m;
+	pid_t			pid;
+	pid_t			rid;
+#if _real_vfork
+	volatile int		exec_errno;
+	volatile int* volatile	exec_errno_ptr;
+#else
+	int			err[2];
+#endif
+#endif
+
+#if 0
+	if (access(path, X_OK))
+		return -1;
+#endif
+	if (!envv)
+		envv = environ;
+#if _lib_spawnve
+#if _lib_fork || _lib_vfork
+	if (!pgid)
+#endif
+		return spawnve(path, argv, envv);
+#endif
+#if _lib_fork || _lib_vfork
+	n = errno;
+#if _real_vfork
+	exec_errno = 0;
+	exec_errno_ptr = &exec_errno;
+#else
+	if (pipe(err) < 0)
+		err[0] = -1;
+	else
+	{
+		fcntl(err[0], F_SETFD, FD_CLOEXEC);
+		fcntl(err[1], F_SETFD, FD_CLOEXEC);
+	}
+#endif
+	sigcritical(SIG_REG_EXEC|SIG_REG_PROC);
+#if _lib_vfork
+	pid = vfork();
+#else
+	pid = fork();
+#endif
+	if (pid == -1)
+		n = errno;
+	else if (!pid)
+	{
+		sigcritical(0);
+		if (pgid == -1)
+			setsid();
+		else if (pgid)
+		{
+			m = 0;
+			if (pgid == 1 || pgid == -2 && (m = 1))
+				pgid = getpid();
+			if (setpgid(0, pgid) < 0 && errno == EPERM)
+				setpgid(pgid, 0);
+#if _lib_tcgetpgrp
+			if (m)
+				tcsetpgrp(2, pgid);
+#else
+#ifdef TIOCSPGRP
+			if (m)
+				ioctl(2, TIOCSPGRP, &pgid);
+#endif
+#endif
+		}
+		execve(path, argv, envv);
+#if _real_vfork
+		*exec_errno_ptr = errno;
+#else
+		if (err[0] != -1)
+		{
+			m = errno;
+			write(err[1], &m, sizeof(m));
+		}
+#endif
+		_exit(errno == ENOENT ? EXIT_NOTFOUND : EXIT_NOEXEC);
+	}
+	rid = pid;
+#if _real_vfork
+	if (pid != -1 && (m = *exec_errno_ptr))
+	{
+		while (waitpid(pid, NiL, 0) == -1 && errno == EINTR);
+		rid = pid = -1;
+		n = m;
+	}
+#else
+	if (err[0] != -1)
+	{
+		close(err[1]);
+		if (pid != -1)
+		{
+			m = 0;
+			while (read(err[0], &m, sizeof(m)) == -1)
+				if (errno != EINTR)
+				{
+					m = errno;
+					break;
+				}
+			if (m)
+			{
+				while (waitpid(pid, &n, 0) && errno == EINTR);
+				rid = pid = -1;
+				n = m;
+			}
+		}
+		close(err[0]);
+	}
+#endif
+	sigcritical(0);
+	if (pid != -1 && pgid > 0)
+	{
+		/*
+		 * parent and child are in a race here
+		 */
+
+		if (pgid == 1)
+			pgid = pid;
+		if (setpgid(pid, pgid) < 0 && pid != pgid && errno == EPERM)
+			setpgid(pid, pid);
+	}
+	errno = n;
+	return rid;
+#else
+	errno = ENOSYS;
+	return -1;
+#endif
+}
+
+#endif
+
+#endif
+
+#endif
+
+#endif