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sys/posix_spawn.c Libc-763.13 /dev/null
--- Libc/Libc-763.13/sys/posix_spawn.c
+++ /dev/null
@@ -1,1407 +0,0 @@
-/*
- * Copyright (c) 2006-2008 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- * 
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
- */
-
-/*
- * [SPN] Support for _POSIX_SPAWN
- */
-
-#include <sys/types.h> /* for user_size_t */
-#include <spawn.h>
-#include <spawn_private.h>
-#include <sys/spawn_internal.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <limits.h>	/* for OPEN_MAX, PATH_MAX */
-#include <stddef.h>	/* for offsetof() */
-#include <string.h>	/* for strlcpy() */
-#include <paths.h>	/* for _PATH_DEFPATH */
-#include <sys/stat.h>	/* for struct stat */
-#include <mach/port.h>
-#include <mach/exception_types.h>
-
-
-/*
- * posix_spawnattr_init
- *
- * Description:	Initialize a spawn attributes object attr with default values
- *
- * Parameters:	attr			The spawn attributes object to be
- *					initialized
- *
- * Returns:	0			Success
- *		ENOMEM			Insufficient memory exists to
- *					initialize the spawn attributes object.
- *
- * Note:	As an implementation detail, the externally visibily type
- *		posix_spawnattr_t is defined to be a void *, and initialization
- *		involves allocation of a memory object.  Subsequent changes to
- *		the spawn attributes may result in reallocation under the
- *		covers.
- *
- *		Reinitialization of an already initialized spawn attributes
- *		object will result in memory being leaked.  Because spawn
- *		attributes are not required to be used in conjunction with a
- *		static initializer, there is no way to distinguish a spawn
- *		attribute with stack garbage from one that's been initialized.
- *		This is arguably an API design error.
- */
-int
-posix_spawnattr_init(posix_spawnattr_t *attr)
-{
-	_posix_spawnattr_t *psattrp = (_posix_spawnattr_t *)attr;
-	int	err = 0;
-
-	if ((*psattrp = (_posix_spawnattr_t)malloc(sizeof(struct _posix_spawnattr))) == NULL) {
-		err = ENOMEM;
-	} else {
-
-		/*
-		 * The default value of this attribute shall be as if no
-		 * flags were set
-		 */
-		(*psattrp)->psa_flags = 0;
-
-		/*
-		 * The default value of this attribute shall be an empty
-		 * signal set
-		 */
-		(*psattrp)->psa_sigdefault = 0;
-
-		/* The default value of this attribute is unspecified */
-		(*psattrp)->psa_sigmask = 0;
-
-		/* The default value of this attribute shall be zero */
-		(*psattrp)->psa_pgroup = 0;	/* doesn't matter */
-
-		/* Default is no binary preferences, i.e. use normal grading */
-		memset((*psattrp)->psa_binprefs, 0, 
-				sizeof((*psattrp)->psa_binprefs));
-
-		/* Default is no port actions to take */
-		(*psattrp)->psa_ports = NULL;
-
-		/*
-		 * The default value of this attribute shall be an no
-		 * process control on resource starvation
-		 */
-		(*psattrp)->psa_pcontrol = 0;
-	}
-
-	return (err);
-}
-
-
-/*
- * posix_spawnattr_destroy
- *
- * Description:	Destroy a spawn attributes object that was previously
- *		initialized via posix_spawnattr_init() by freeing any
- *		memory associated with it and setting it to an invalid value.
- *
- * Parameters:	attr			The spawn attributes object to be
- *					destroyed.
- *
- * Returns:	0			Success
- *
- * Notes:	The destroyed spawn attribute results in the void * pointer
- *		being set to NULL; subsequent use without reinitialization
- *		will result in explicit program failure (rather than merely
- *		"undefined behaviour").
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by attr is invalid.
- */
-static int posix_spawn_destroyportactions_np(posix_spawnattr_t *);
-
-int
-posix_spawnattr_destroy(posix_spawnattr_t *attr)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	posix_spawn_destroyportactions_np(attr);
-
-	free(psattr);
-	*attr = NULL;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_setflags
- *
- * Description:	Set the spawn flags attribute for the spawn attribute object
- *		referred to by 'attr'.
- *
- * Parameters:	attr			The spawn attributes object whose flags
- *					are to be set
- *		flags			The flags value to set
- *
- * Returns:	0			Success
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by attr is invalid.
- *		EINVAL	The value of the attribute being set is not valid.
- */
-int
-posix_spawnattr_setflags(posix_spawnattr_t *attr, short flags)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	psattr->psa_flags = flags;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_getflags
- *
- * Description:	Retrieve the spawn attributes flag for the spawn attributes
- *		object referenced by 'attr' and place them in the memory
- *		location referenced by 'flagsp'
- *
- * Parameters:	attr			The spawn attributes object whose flags
- *					are to be retrieved
- *		flagsp			A pointer to a short value to receive
- *					the flags
- *
- * Returns:	0			Success
- *
- * Implicit Returns:
- *		*flagps (modified)	The flags value from the spawn
- *					attributes object
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by attr is invalid.
- *		EINVAL	The value of the attribute being set is not valid.
- */
-int
-posix_spawnattr_getflags(const posix_spawnattr_t * __restrict attr,
-	short * __restrict flagsp)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	*flagsp = psattr->psa_flags;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_getsigdefault
- *
- * Description:	Retrieve the set of signals to be set to default according to
- *		the spawn attribute value referenced by 'attr' and place the
- *		result into the memory containing the sigset_t referenced by
- *		'sigdefault'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					signal set for default signals is to
- *					be retrieved
- *		sigdefault		A pointer to the sigset_t to receive
- *					the signal set
- *
- * Returns:	0			Success
- *
- * Implicit Returns:
- *		*sigdefault (modified)	The signal set of signals to default
- *					from the spawn attributes object
- */
-int
-posix_spawnattr_getsigdefault(const posix_spawnattr_t * __restrict attr,
-		sigset_t * __restrict sigdefault)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	*sigdefault = psattr->psa_sigdefault;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_getpgroup
- *
- * Description:	Obtain the value of the spawn process group attribute from the
- *		spawn attributes object referenced by 'attr' and place the
- *		results in the memory location referenced by 'pgroup'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					process group information is to be
- *					retrieved
- *		pgroup			A pointer to the pid_t to receive the
- *					process group
- *
- * Returns:	0			Success
- *
- * Implicit Returns:
- *		*pgroup (modified)	The process group information from the
- *					spawn attributes object
- */
-int
-posix_spawnattr_getpgroup(const posix_spawnattr_t * __restrict attr,
-		pid_t * __restrict pgroup)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	*pgroup = psattr->psa_pgroup;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_getsigmask
- *
- * Description:	Obtain the value of the spawn signal mask attribute from the
- *		spawn attributes object referenced by 'attr' and place the
- *		result into the memory containing the sigset_t referenced by
- *		'sigmask'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					signal set for masked signals is to
- *					be retrieved
- *		sigmask		A pointer to the sigset_t to receive
- *					the signal set
- *
- * Returns:	0			Success
- *
- * Implicit Returns:
- *		*sigmask (modified)	The signal set of signals to mask
- *					from the spawn attributes object
- */
-int
-posix_spawnattr_getsigmask(const posix_spawnattr_t * __restrict attr,
-		sigset_t * __restrict sigmask)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	*sigmask = psattr->psa_sigmask;
-
-	return (0);
-}
-
-/*
- * posix_spawnattr_getbinpref_np
- *
- * Description:	Obtain the value of the spawn binary preferences attribute from 
- * 		the spawn attributes object referenced by 'attr' and place the
- *		result into the memory referenced by 'pref'.
- *
- * Parameters:	attr			The spawn attributes object whose
- *					binary preferences are to be retrieved
- *		count			The size of the cpu_type_t array
- *		pref			An array of cpu types
- *		ocount			The actual number copied
- *
- * Returns:	0			No binary preferences found
- * 		> 0			The number of cpu types (less than 
- * 					count) copied over from 'attr'.
- *
- * Implicit Returns:
- *		*pref (modified)	The binary preferences array 
- *					from the spawn attributes object
- */
-int
-posix_spawnattr_getbinpref_np(const posix_spawnattr_t * __restrict attr,
-		size_t count, cpu_type_t *pref, size_t * __restrict ocount)
-{
-	_posix_spawnattr_t psattr;
-	int i = 0;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	for (i = 0; i < count && i < 4; i++) {
-		pref[i] = psattr->psa_binprefs[i];
-	}
-
-	if (ocount)
-		*ocount = i;
-	return 0;
-}
-
-
-/*
- * posix_spawnattr_getpcontrol_np
- *
- * Description:	Retrieve the  process control property set default according to
- *		the spawn attribute value referenced by 'attr' and place the
- *		result into the memory containing the control  referenced by
- *		'pcontrol'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					signal set for default signals is to
- *					be retrieved
- *		pcontrol		A pointer to an int  to receive
- *					the process control info
- *
- * Returns:	0			Success
- *
- * Implicit Returns:
- *		*pcontrol (modified)	The signal set of signals to default
- *					from the spawn attributes object
- */
-int
-posix_spawnattr_getpcontrol_np(const posix_spawnattr_t * __restrict attr,
-		int * __restrict pcontrol)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	*pcontrol = psattr->psa_pcontrol;
-
-	return (0);
-}
-
-/*
- * posix_spawnattr_setsigdefault
- *
- * Description:	Set the set of signals to be set to default for the spawn
- *		attribute value referenced by 'attr' from the memory
- *		containing the sigset_t referenced by 'sigdefault'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					signal set for default signals is to
- *					be set
- *		sigdefault		A pointer to the sigset_t from which to
- *					obtain the signal set
- *
- * Returns:	0			Success
- */
-int
-posix_spawnattr_setsigdefault(posix_spawnattr_t * __restrict attr,
-		const sigset_t * __restrict sigdefault)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	psattr->psa_sigdefault = *sigdefault;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_setpgroup
- *
- * Description:	Set the value of the spawn process group attribute for the
- *		spawn attributes object referenced by 'attr' from the value
- *		of 'pgroup'
- *
- * Parameters:	attr			The spawn attributes object for which
- *					the process group information is to be
- *					set
- *		pgroup			The process group to set
- *
- * Returns:	0			Success
- */
-int
-posix_spawnattr_setpgroup(posix_spawnattr_t * attr, pid_t pgroup)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	psattr->psa_pgroup = pgroup;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_setsigmask
- *
- * Description:	Set the set of signals to be masked for the spawn attribute
- *		value referenced by 'attr' from the memory containing the
- *		sigset_t referenced by 'sigmask'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					signal set for masked signals is to
- *					be set
- *		sigmask		A pointer to the sigset_t from which to
- *					obtain the signal set
- *
- * Returns:	0			Success
- */
-int
-posix_spawnattr_setsigmask(posix_spawnattr_t * __restrict attr,
-		const sigset_t * __restrict sigmask)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	psattr->psa_sigmask = *sigmask;
-
-	return (0);
-}
-
-
-/*
- * posix_spawnattr_setbinpref_np
- *
- * Description:	Set the universal binary preferences for the spawn attribute
- *		value referenced by 'attr' from the memory containing the
- *		cpu_type_t array referenced by 'pref', size of 'count'
- *
- * Parameters:	attr			The spawn attributes object whose
- * 					binary preferences are to be set
- * 		count			Size of the array pointed to by 'pref'
- * 		pref			cpu_type_t array of binary preferences
- *		ocount			The actual number copied
- *
- * Returns:	0			No preferences copied
- * 		> 0			Number of preferences copied
- *
- * Note:	The posix_spawnattr_t currently only holds four cpu_type_t's. 
- * 		If the caller provides more preferences than this limit, they
- * 		will be ignored, as reflected in the return value.
- */
-int
-posix_spawnattr_setbinpref_np(posix_spawnattr_t * __restrict attr,
-		size_t count, cpu_type_t *pref, size_t * __restrict ocount)
-{
-	_posix_spawnattr_t psattr;
-	int i = 0;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	for (i = 0; i < count && i < 4; i++) {
-		psattr->psa_binprefs[i] = pref[i];
-	}
-
-	/* return number of binprefs copied over */
-	if (ocount)
-		*ocount = i;
-	return 0;
-}
-
-
-/*
- * posix_spawnattr_setpcontrol_np
- *
- * Description:	Set the process control property according to
- *		attribute value referenced by 'attr' from the memory
- *		containing the int value 'pcontrol'
- *
- * Parameters:	attr			The spawn attributes object whose
- *					signal set for default signals is to
- *					be set
- *		pcontrol		An int value of the process control info
- *
- * Returns:	0			Success
- */
-int
-posix_spawnattr_setpcontrol_np(posix_spawnattr_t * __restrict attr,
-		const int pcontrol)
-{
-	_posix_spawnattr_t psattr;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	psattr->psa_pcontrol = pcontrol;
-
-	return (0);
-}
-/*
- * posix_spawn_createportactions_np
- * Description: create a new posix_spawn_port_actions struct and link
- * 	it into the posix_spawnattr.
- */
-static int
-posix_spawn_createportactions_np(posix_spawnattr_t *attr)
-{
-	_posix_spawnattr_t psattr;
-	_posix_spawn_port_actions_t acts;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	acts = (_posix_spawn_port_actions_t)malloc(PS_PORT_ACTIONS_SIZE(2));
-	if (acts == NULL)
-		return ENOMEM;
-	
-	acts->pspa_alloc = 2;
-	acts->pspa_count = 0;
-
-	psattr->psa_ports = acts;
-	return 0;
-}
-
-/*
- * posix_spawn_growportactions_np
- * Description: Enlarge the size of portactions if necessary 
- */
-static int
-posix_spawn_growportactions_np(posix_spawnattr_t *attr)
-{
-	_posix_spawnattr_t psattr;
-	_posix_spawn_port_actions_t acts; 
-	int newnum;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	acts = psattr->psa_ports; 
-	if (acts == NULL)
-		return EINVAL;
-	
-	/* Double number of port actions allocated for */
-	newnum = 2 * acts->pspa_alloc;
-	acts = realloc(acts, PS_PORT_ACTIONS_SIZE(newnum));
-	if (acts == NULL)
-		return ENOMEM;
-	
-	acts->pspa_alloc = newnum;
-	return 0;
-}
-
-/*
- * posix_spawn_destroyportactions_np
- * Description: clean up portactions struct in posix_spawnattr_t attr
- */
-static int
-posix_spawn_destroyportactions_np(posix_spawnattr_t *attr)
-{
-	_posix_spawnattr_t psattr;
-	_posix_spawn_port_actions_t acts; 
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	acts = psattr->psa_ports; 
-	if (acts == NULL)
-		return EINVAL;
-	
-	free(acts);
-	return 0;
-}
-
-
-/*
- * posix_spawnattr_setspecialport_np
- *
- * Description:	Set a new value for a mach special port in the spawned task. 
- *
- * Parameters:	attr			The spawn attributes object for the
- * 					new process
- * 		new_port		The new value for the special port
- * 		which			The particular port to be set
- * 					(see task_set_special_port for details)
- *
- * Returns:	0			Success
- * 		ENOMEM			Couldn't allocate memory
- */
-int    
-posix_spawnattr_setspecialport_np(
-		posix_spawnattr_t *attr,
-		mach_port_t      new_port,
-		int             which)
-{
-	_posix_spawnattr_t psattr;
-	int err = 0;
-	_ps_port_action_t *action;
-	_posix_spawn_port_actions_t ports;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	ports = psattr->psa_ports;
-	/* Have any port actions been created yet? */
-	if (ports == NULL) {
-		err = posix_spawn_createportactions_np(attr);
-		if (err) 
-			return err;
-		ports = psattr->psa_ports;
-	}
-	
-	/* Is there enough room? */
-	if (ports->pspa_alloc == ports->pspa_count) {
-		err = posix_spawn_growportactions_np(attr);
-		if (err)
-			return err;
-	}
-
-	/* Add this action to next spot in array */
-	action = &ports->pspa_actions[ports->pspa_count];
-	action->port_type = PSPA_SPECIAL;
-	action->new_port = new_port;
-	action->which = which;
-	
-	ports->pspa_count++;
-	return err;
-}
-
-/*
- * posix_spawnattr_setexceptionports_np
- *
- * Description:	Set a new port for a set of exception ports in the spawned task.
- *
- * Parameters:	attr			The spawn attributes object for the
- * 					new process
- * 		mask			A bitfield indicating which exceptions
- * 					to associate the port with
- * 		new_port		The new value for the exception port
- * 		behavior		The default behavior for the port
- * 		flavor			The default flavor for the port
- * 					(see task_set_exception_ports)
- *
- * Returns:	0			Success
- */
-int    
-posix_spawnattr_setexceptionports_np(
-		posix_spawnattr_t       *attr,
-		exception_mask_t        mask,
-		mach_port_t              new_port,
-		exception_behavior_t    behavior,
-		thread_state_flavor_t   flavor)
-{
-	_posix_spawnattr_t psattr;
-	int err = 0;
-	_ps_port_action_t *action;
-	_posix_spawn_port_actions_t ports;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	ports = psattr->psa_ports;
-	/* Have any port actions been created yet? */
-	if (ports == NULL) {
-		err = posix_spawn_createportactions_np(attr);
-		if (err) 
-			return err;
-		ports = psattr->psa_ports;
-	}
-	
-	/* Is there enough room? */
-	if (ports->pspa_alloc == ports->pspa_count) {
-		err = posix_spawn_growportactions_np(attr);
-		if (err)
-			return err;
-	}
-
-	/* Add this action to next spot in array */
-	action = &ports->pspa_actions[ports->pspa_count];
-	action->port_type = PSPA_EXCEPTION;
-	action->mask = mask;
-	action->new_port = new_port;
-	action->behavior = behavior;
-	action->flavor = flavor;
-	
-	ports->pspa_count++;
-	return err;
-}
-
-/*
- * posix_spawnattr_setauditsessionport_np
- *
- * Description:	Set the audit session port rights attribute in the spawned task.
- *		This is used to securely set the audit session information for
- *		the new task.
- *
- * Parameters:	attr			The spawn attributes object for the
- * 					new process
- * 		au_sessionport		The audit session send port right
- *
- * Returns:	0			Success
- */
-int    
-posix_spawnattr_setauditsessionport_np(
-		posix_spawnattr_t       *attr,
-		mach_port_t              au_sessionport)
-{
-	_posix_spawnattr_t psattr;
-	int err = 0;
-	_ps_port_action_t *action;
-	_posix_spawn_port_actions_t ports;
-
-	if (attr == NULL || *attr == NULL)
-		return EINVAL;
-
-	psattr = *(_posix_spawnattr_t *)attr;
-	ports = psattr->psa_ports;
-	/* Have any port actions been created yet? */
-	if (ports == NULL) {
-		err = posix_spawn_createportactions_np(attr);
-		if (err) 
-			return err;
-		ports = psattr->psa_ports;
-	}
-	
-	/* Is there enough room? */
-	if (ports->pspa_alloc == ports->pspa_count) {
-		err = posix_spawn_growportactions_np(attr);
-		if (err)
-			return err;
-	}
-
-	/* Add this action to next spot in array */
-	action = &ports->pspa_actions[ports->pspa_count];
-	action->port_type = PSPA_AU_SESSION;
-	action->new_port = au_sessionport;
-	
-	ports->pspa_count++;
-	return err;
-}
-
-
-/*
- * posix_spawn_file_actions_init
- *
- * Description:	Initialize a spawn file actions object attr with default values
- *
- * Parameters:	file_actions		The spawn file actions object to be
- *					initialized
- *
- * Returns:	0			Success
- *		ENOMEM			Insufficient memory exists to
- *					initialize the spawn file actions
- *					object.
- *
- * Note:	As an implementation detail, the externally visibily type
- *		posix_spawn_file_actions_t is defined to be a void *, and
- *		initialization involves allocation of a memory object.
- *		Subsequent changes to the spawn file actions may result in
- *		reallocation under the covers.
- *
- *		Reinitialization of an already initialized spawn file actions
- *		object will result in memory being leaked.  Because spawn
- *		file actions are not required to be used in conjunction with a
- *		static initializer, there is no way to distinguish a spawn
- *		file actions with stack garbage from one that's been
- *		initialized.  This is arguably an API design error.
- */
-int
-posix_spawn_file_actions_init(posix_spawn_file_actions_t *file_actions)
-{
-	_posix_spawn_file_actions_t *psactsp = (_posix_spawn_file_actions_t *)file_actions;
-	int	err = 0;
-
-	if ((*psactsp = (_posix_spawn_file_actions_t)malloc(PSF_ACTIONS_SIZE(PSF_ACTIONS_INIT_COUNT))) == NULL) {
-		err = ENOMEM;
-	} else {
-		(*psactsp)->psfa_act_alloc = PSF_ACTIONS_INIT_COUNT;
-		(*psactsp)->psfa_act_count = 0;
-	}
-
-	return (err);
-}
-
-
-/*
- * posix_spawn_file_actions_destroy
- *
- * Description:	Destroy a spawn file actions object that was previously
- *		initialized via posix_spawn_file_actions_init() by freeing any
- *		memory associated with it and setting it to an invalid value.
- *
- * Parameters:	attr			The spawn file actions object to be
- *					destroyed.
- *
- * Returns:	0			Success
- *
- * Notes:	The destroyed spawn file actions results in the void * pointer
- *		being set to NULL; subsequent use without reinitialization
- *		will result in explicit program failure (rather than merely
- *		"undefined behaviour").
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by file_actions is invalid.
- */
-int
-posix_spawn_file_actions_destroy(posix_spawn_file_actions_t *file_actions)
-{
-	_posix_spawn_file_actions_t psacts;
-
-	if (file_actions == NULL || *file_actions == NULL)
-		return EINVAL;
-
-	psacts = *(_posix_spawn_file_actions_t *)file_actions;
-	free(psacts);
-	*file_actions = NULL;
-
-	return (0);
-}
-
-
-/*
- * _posix_spawn_file_actions_grow
- *
- * Description:	Grow the available list of file actions associated with the
- *		pointer to the structure provided; replace the contents of the
- *		pointer as a side effect.
- *
- * Parameters:	psactsp			Pointer to _posix_spawn_file_actions_t
- *					to grow
- *
- * Returns:	0			Success
- *		ENOMEM			Insufficient memory for operation
- *
- * Notes:	This code is common to all posix_spawn_file_actions_*()
- *		functions, since we use a naieve data structure implementation
- *		at present.  Future optimization will likely change this.
- */
-static int
-_posix_spawn_file_actions_grow(_posix_spawn_file_actions_t *psactsp)
-{
-	int	new_alloc = (*psactsp)->psfa_act_alloc * 2;
-	_posix_spawn_file_actions_t new_psacts;
-
-	/*
-	 * XXX may want to impose an administrative limit here; POSIX does
-	 * XXX not provide for an administrative error return in this case,
-	 * XXX so it's probably acceptable to just fail catastrophically
-	 * XXX instead of implementing one.
-	 */
-	if ((new_psacts = (_posix_spawn_file_actions_t)realloc((*psactsp), PSF_ACTIONS_SIZE(new_alloc))) == NULL) {
-		return (ENOMEM);
-	}
-	new_psacts->psfa_act_alloc = new_alloc;
-	*psactsp = new_psacts;
-
-	return (0);
-}
-
-
-/*
- * posix_spawn_file_actions_addopen
- *
- * Description:	Add an open action to the object referenced by 'file_actions'
- *		that will cause the file named by 'path' to be attempted to be
- *		opened with flags 'oflag' and mode 'mode', and, if successful,
- *		return as descriptor 'filedes' to the spawned process.
- *
- * Parameters:	file_actions		File action object to augment
- *		filedes			fd that open is to use
- *		path			path to file to open
- *		oflag			open file flags
- *		mode			open file mode
- *
- * Returns:	0			Success
- *		EBADF			The value specified by fildes is
- *					negative or greater than or equal to
- *					{OPEN_MAX}.
- *		ENOMEM			Insufficient memory exists to add to
- *					the spawn file actions object.
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by file_actions is invalid.
- */
-int
-posix_spawn_file_actions_addopen(
-		posix_spawn_file_actions_t * __restrict file_actions,
-		int filedes, const char * __restrict path, int oflag,
-		mode_t mode)
-{
-	_posix_spawn_file_actions_t *psactsp;
-	_psfa_action_t *psfileact;
-
-	if (file_actions == NULL || *file_actions == NULL)
-		return EINVAL;
-
-	psactsp = (_posix_spawn_file_actions_t *)file_actions;
-	/* Range check; required by POSIX */
-	if (filedes < 0 || filedes >= OPEN_MAX)
-		return (EBADF);
-
-	/* If we do not have enough slots, grow the structure */
-	if ((*psactsp)->psfa_act_count == (*psactsp)->psfa_act_alloc) {
-		/* need to grow file actions structure */
-		if (_posix_spawn_file_actions_grow(psactsp))
-			return (ENOMEM);
-	}
-
-	/*
-	 * Allocate next available slot and fill it out
-	 */
-	psfileact = &(*psactsp)->psfa_act_acts[(*psactsp)->psfa_act_count++];
-
-	psfileact->psfaa_type = PSFA_OPEN;
-	psfileact->psfaa_filedes = filedes;
-	psfileact->psfaa_openargs.psfao_oflag = oflag;
-	psfileact->psfaa_openargs.psfao_mode = mode;
-	strlcpy(psfileact->psfaa_openargs.psfao_path, path, PATH_MAX);
-
-	return (0);
-}
-
-
-/*
- * posix_spawn_file_actions_addclose
- *
- * Description:	Add a close action to the object referenced by 'file_actions'
- *		that will cause the file referenced by 'filedes' to be
- *		attempted to be closed in the spawned process.
- *
- * Parameters:	file_actions		File action object to augment
- *		filedes			fd to close
- *
- * Returns:	0			Success
- *		EBADF			The value specified by fildes is
- *					negative or greater than or equal to
- *					{OPEN_MAX}.
- *		ENOMEM			Insufficient memory exists to add to
- *					the spawn file actions object.
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by file_actions is invalid.
- */
-int
-posix_spawn_file_actions_addclose(posix_spawn_file_actions_t *file_actions,
-		int filedes)
-{
-	_posix_spawn_file_actions_t *psactsp;
-	_psfa_action_t *psfileact;
-
-	if (file_actions == NULL || *file_actions == NULL)
-		return EINVAL;
-
-	psactsp = (_posix_spawn_file_actions_t *)file_actions;
-	/* Range check; required by POSIX */
-	if (filedes < 0 || filedes >= OPEN_MAX)
-		return (EBADF);
-
-	/* If we do not have enough slots, grow the structure */
-	if ((*psactsp)->psfa_act_count == (*psactsp)->psfa_act_alloc) {
-		/* need to grow file actions structure */
-		if (_posix_spawn_file_actions_grow(psactsp))
-			return (ENOMEM);
-	}
-
-	/*
-	 * Allocate next available slot and fill it out
-	 */
-	psfileact = &(*psactsp)->psfa_act_acts[(*psactsp)->psfa_act_count++];
-
-	psfileact->psfaa_type = PSFA_CLOSE;
-	psfileact->psfaa_filedes = filedes;
-
-	return (0);
-}
-
-
-/*
- * posix_spawn_file_actions_adddup2
- *
- * Description:	Add a dup2 action to the object referenced by 'file_actions'
- *		that will cause the file referenced by 'filedes' to be
- *		attempted to be dup2'ed to the descriptor 'newfiledes' in the
- *		spawned process.
- *
- * Parameters:	file_actions		File action object to augment
- *		filedes			fd to dup2
- *		newfiledes		fd to dup2 it to
- *
- * Returns:	0			Success
- *		EBADF			The value specified by either fildes
- *					or by newfiledes is negative or greater
- *					than or equal to {OPEN_MAX}.
- *		ENOMEM			Insufficient memory exists to add to
- *					the spawn file actions object.
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by file_actions is invalid.
- */
-int
-posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *file_actions,
-		int filedes, int newfiledes)
-{
-	_posix_spawn_file_actions_t *psactsp;
-	_psfa_action_t *psfileact;
-
-	if (file_actions == NULL || *file_actions == NULL)
-		return EINVAL;
-
-	psactsp = (_posix_spawn_file_actions_t *)file_actions;
-	/* Range check; required by POSIX */
-	if (filedes < 0 || filedes >= OPEN_MAX ||
-	    newfiledes < 0 || newfiledes >= OPEN_MAX)
-		return (EBADF);
-
-	/* If we do not have enough slots, grow the structure */
-	if ((*psactsp)->psfa_act_count == (*psactsp)->psfa_act_alloc) {
-		/* need to grow file actions structure */
-		if (_posix_spawn_file_actions_grow(psactsp))
-			return (ENOMEM);
-	}
-
-	/*
-	 * Allocate next available slot and fill it out
-	 */
-	psfileact = &(*psactsp)->psfa_act_acts[(*psactsp)->psfa_act_count++];
-
-	psfileact->psfaa_type = PSFA_DUP2;
-	psfileact->psfaa_filedes = filedes;
-	psfileact->psfaa_openargs.psfao_oflag = newfiledes;
-
-	return (0);
-}
-
-/*
- * posix_spawn_file_actions_addinherit_np
- *
- * Description:	Add the "inherit" action to the object referenced by
- *		'file_actions' that will cause the file referenced by
- *		'filedes' to continue to be available in the spawned
- *		process via the same descriptor.
- *
- *		Inheritance is the normal default behaviour for
- *		file descriptors across exec and spawn; but if the
- *		POSIX_SPAWN_CLOEXEC_DEFAULT flag is set, the usual
- *		default is reversed for the purposes of the spawn
- *		invocation.  Any pre-existing descriptors that
- *		need to be made available to the spawned process can
- *		be marked explicitly as 'inherit' via this interface.
- *		Otherwise they will be automatically closed.
- *
- *		Note that any descriptors created via the other file
- *		actions interfaces are automatically marked as 'inherit'.
- *
- * Parameters:	file_actions		File action object to augment
- *		filedes			fd to inherit.
- *
- * Returns:	0			Success
- *		EBADF			The value specified by fildes is
- *					negative or greater than or equal to
- *					{OPEN_MAX}.
- *		ENOMEM			Insufficient memory exists to add to
- *					the spawn file actions object.
- *
- * NOTIMP:	Allowed failures (checking NOT required):
- *		EINVAL	The value specified by file_actions is invalid.
- */
-int
-posix_spawn_file_actions_addinherit_np(posix_spawn_file_actions_t *file_actions,
-		int filedes)
-{
-	_posix_spawn_file_actions_t *psactsp;
-	_psfa_action_t *psfileact;
-
-	if (file_actions == NULL || *file_actions == NULL)
-		return (EINVAL);
-
-	psactsp = (_posix_spawn_file_actions_t *)file_actions;
-	/* Range check; required by POSIX */
-	if (filedes < 0 || filedes >= OPEN_MAX)
-		return (EBADF);
-
-#if defined(POSIX_SPAWN_CLOEXEC_DEFAULT)	// TODO: delete this check
-	/* If we do not have enough slots, grow the structure */
-	if ((*psactsp)->psfa_act_count == (*psactsp)->psfa_act_alloc) {
-		/* need to grow file actions structure */
-		if (_posix_spawn_file_actions_grow(psactsp))
-			return (ENOMEM);
-	}
-
-	/*
-	 * Allocate next available slot and fill it out
-	 */
-	psfileact = &(*psactsp)->psfa_act_acts[(*psactsp)->psfa_act_count++];
-
-	psfileact->psfaa_type = PSFA_INHERIT;
-	psfileact->psfaa_filedes = filedes;
-#endif
-	return (0);
-}
-
-
-/*
- * posix_spawnp
- *
- * Description:	Create a new process from the process image corresponding to
- *		the supplied 'file' argument and the parent processes path
- *		environment.
- *
- * Parameters:	pid				Pointer to pid_t to receive the
- *						PID of the spawned process, if
- *						successful and 'pid' != NULL
- *		file				Name of image file to spawn
- *		file_actions			spawn file actions object which
- *						describes file actions to be
- *						performed during the spawn
- *		attrp				spawn attributes object which
- *						describes attributes to be
- *						applied during the spawn
- *		argv				argument vector array; NULL
- *						terminated
- *		envp				environment vector array; NULL
- *						terminated
- *
- * Returns:	0				Success
- *		!0				An errno value indicating the
- *						cause of the failure to spawn
- *
- * Notes:	Much of this function is derived from code from execvP() from
- *		exec.c in libc; this common code should be factored out at
- *		some point to prevent code duplication or desynchronization vs.
- *		bug fixes applied to one set of code but not the other.
- */
-int
-posix_spawnp(pid_t * __restrict pid, const char * __restrict file,
-		const posix_spawn_file_actions_t *file_actions,
-		const posix_spawnattr_t * __restrict attrp,
-		char *const argv[ __restrict], char *const envp[ __restrict])
-{
-	const char *env_path;
-	char *bp;
-	char *cur;
-	char *p;
-	char **memp;
-	int lp;
-	int ln;
-	int cnt;
-	int err = 0;
-	int eacces = 0;
-	struct stat sb;
-	char path_buf[PATH_MAX];
-
-	if ((env_path = getenv("PATH")) == NULL)
-		env_path = _PATH_DEFPATH;
-
-	/* If it's an absolute or relative path name, it's easy. */
-	if (index(file, '/')) {
-		bp = (char *)file;
-		cur = NULL;
-		goto retry;
-	}
-	bp = path_buf;
-
-	/* If it's an empty path name, fail in the usual POSIX way. */
-	if (*file == '\0')
-		return (ENOENT);
-
-	if ((cur = alloca(strlen(env_path) + 1)) == NULL)
-		return ENOMEM;
-	strcpy(cur, env_path);
-	while ((p = strsep(&cur, ":")) != NULL) {
-		/*
-		 * It's a SHELL path -- double, leading and trailing colons
-		 * mean the current directory.
-		 */
-		if (*p == '\0') {
-			p = ".";
-			lp = 1;
-		} else {
-			lp = strlen(p);
-		}
-		ln = strlen(file);
-
-		/*
-		 * If the path is too long complain.  This is a possible
-		 * security issue; given a way to make the path too long
-		 * the user may spawn the wrong program.
-		 */
-		if (lp + ln + 2 > sizeof(path_buf)) {
-			err = ENAMETOOLONG;
-			goto done;
-		}
-		bcopy(p, path_buf, lp);
-		path_buf[lp] = '/';
-		bcopy(file, path_buf + lp + 1, ln);
-		path_buf[lp + ln + 1] = '\0';
-
-retry:		err = posix_spawn(pid, bp, file_actions, attrp, argv, envp);
-		switch (err) {
-		case E2BIG:
-		case ENOMEM:
-		case ETXTBSY:
-			goto done;
-		case ELOOP:
-		case ENAMETOOLONG:
-		case ENOENT:
-		case ENOTDIR:
-			break;
-		case ENOEXEC:
-			for (cnt = 0; argv[cnt]; ++cnt)
-				;
-			memp = alloca((cnt + 2) * sizeof(char *));
-			if (memp == NULL) {
-				/* errno = ENOMEM; XXX override ENOEXEC? */
-				goto done;
-			}
-			memp[0] = "sh";
-			memp[1] = bp;
-			bcopy(argv + 1, memp + 2, cnt * sizeof(char *));
-			err = posix_spawn(pid, _PATH_BSHELL, file_actions, attrp, memp, envp);
-			goto done;
-		default:
-			/*
-			 * EACCES may be for an inaccessible directory or
-			 * a non-executable file.  Call stat() to decide
-			 * which.  This also handles ambiguities for EFAULT
-			 * and EIO, and undocumented errors like ESTALE.
-			 * We hope that the race for a stat() is unimportant.
-			 */
-			if (stat(bp, &sb) != 0)
-				break;
-			if (err == EACCES) {
-				eacces = 1;
-				continue;
-			}
-			goto done;
-		}
-	}
-	if (eacces)
-		err = EACCES;
-	else
-		err = ENOENT;
-done:
-	return (err);
-}
-
-
-/*
- * posix_spawn
- *
- * Description:	Create a new process from the process image corresponding to
- *		the supplied 'path' argument.
- *
- * Parameters:	pid				Pointer to pid_t to receive the
- *						PID of the spawned process, if
- *						successful and 'pid' != NULL
- *		path				Path of image file to spawn
- *		file_actions			spawn file actions object which
- *						describes file actions to be
- *						performed during the spawn
- *		attrp				spawn attributes object which
- *						describes attributes to be
- *						applied during the spawn
- *		argv				argument vector array; NULL
- *						terminated
- *		envp				environment vector array; NULL
- *						terminated
- *
- * Returns:	0				Success
- *		!0				An errno value indicating the
- *						cause of the failure to spawn
- *
- * Notes:	Unlike other system calls, the return value of this system
- *		call is expected to either be a 0 or an errno, rather than a
- *		0 or a -1, with the 'errno' variable being set.
- */
-extern int __posix_spawn(pid_t * __restrict, const char * __restrict,
-		struct _posix_spawn_args_desc *,
-		char *const argv[ __restrict], char *const envp[ __restrict]);
-
-int
-posix_spawn(pid_t * __restrict pid, const char * __restrict path,
-		const posix_spawn_file_actions_t *file_actions,
-		const posix_spawnattr_t * __restrict attrp,
-		char *const argv[ __restrict], char *const envp[ __restrict])
-{
-	int saveerrno = errno;
-	int ret;
-	/*
-	 * Only do extra work if we have file actions or attributes to push
-	 * down.  We use a descriptor to push this information down, since we
-	 * want to have size information, which will let us (1) preallocate a
-	 * single chunk of memory for the copyin(), and (2) allow us to do a
-	 * single copyin() per attributes or file actions as a monlithic block.
-	 *
-	 * Note:	A future implementation may attempt to do the same
-	 *		thing for the argv/envp data, which could potentially
-	 *		result in a performance improvement due to increased
-	 *		kernel efficiency, even though it would mean copying
-	 *		the data in user space.
-	 */
-	if ((file_actions != NULL && (*file_actions != NULL) &&	(*(_posix_spawn_file_actions_t *)file_actions)->psfa_act_count > 0) || attrp != NULL) {
-		struct _posix_spawn_args_desc	ad;
-
-		memset(&ad, 0, sizeof(ad));
-		if (attrp != NULL && *attrp != NULL) {
-			_posix_spawnattr_t psattr = *(_posix_spawnattr_t *)attrp;
-			ad.attr_size = sizeof(struct _posix_spawnattr);
-			ad.attrp = psattr;
-
-			if (psattr->psa_ports != NULL) {
-				ad.port_actions = psattr->psa_ports;
-				ad.port_actions_size = PS_PORT_ACTIONS_SIZE(
-						ad.port_actions->pspa_count);
-			}
-		}
-		if (file_actions != NULL && *file_actions != NULL) {
-			_posix_spawn_file_actions_t psactsp =
-				*(_posix_spawn_file_actions_t *)file_actions;
-
-			if (psactsp->psfa_act_count > 0) {
-				ad.file_actions_size = PSF_ACTIONS_SIZE(psactsp->psfa_act_count);
-				ad.file_actions = psactsp;
-			}
-		}
-
-		ret = __posix_spawn(pid, path, &ad, argv, envp);
-	} else
-		ret = __posix_spawn(pid, path, NULL, argv, envp);
-
-	if (ret < 0)
-		ret = errno;
-	errno = saveerrno;
-	return ret;
-}
-