OpenSolaris_b135/lib/libinstzones/common/zones_args.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Module: zones_args.c
* Group: libinstzones
* Description: Private functions used by zones library functions to manipulate
* argument lists
*
* Public Methods:
*
* _z_add_arg - add new argument to argument array for use in exec() calls
* _z_free_args - free all storage contained in an argument array previously
* _z_get_argc - return (int) argc count from argument array
* _z_get_argv - return (char **)argv pointer from argument array
* _z_new_args - create a new argument array for use in exec() calls
*/
/*
* System includes
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/param.h>
#include <string.h>
#include <strings.h>
#include <stdarg.h>
#include <limits.h>
#include <errno.h>
#include <stropts.h>
#include <libintl.h>
#include <locale.h>
#include <assert.h>
/*
* local includes
*/
#include "instzones_lib.h"
#include "zones_strings.h"
/*
* Private structures
*/
/*
* Library Function Prototypes
*/
/*
* Local Function Prototypes
*/
/*
* Global internal (private) declarations
*/
/*
* *****************************************************************************
* global external (public) functions
* *****************************************************************************
*/
/*
* Name: _z_add_arg
* Description: add new argument to argument array for use in exec() calls
* Arguments: a_args - [RO, *RW] - (argArray_t *)
* Pointer to argument array (previously allocated via
* a call to _z_new_args) to add the argument to
* a_format - [RO, *RO] - (char *)
* Pointer to "printf(3C)" style format argument
* ... - [RO, *RO] - (varies)
* Arguments as appropriate for format argument specified
* Returns: boolean_t
* B_TRUE - success
* B_FALSE - failure
* Examples:
* - to add an argument that specifies a file descriptor:
* int fd;
* _z_add_arg(aa, "/proc/self/fd/%d", fd);
* - to add a flag or other known text:
* _z_add_arg(aa, "-s")
* - to add random text:
* char *random_text;
* _z_add_arg(aa, "%s", random_text);
*/
/*PRINTFLIKE2*/
boolean_t
_z_add_arg(argArray_t *a_args, char *a_format, ...)
{
char *rstr = NULL;
char bfr[MAX_CANON];
size_t vres = 0;
va_list ap;
/* entry assertions */
assert(a_args != NULL);
assert(a_format != NULL);
assert(*a_format != '\0');
/*
* double argument array if array is full
*/
if (a_args->_aaNumArgs >= a_args->_aaMaxArgs) {
int newMax;
char **newArgs;
newMax = a_args->_aaMaxArgs * 2;
newArgs = (char **)_z_realloc(a_args->_aaArgs,
(newMax+1) * sizeof (char *));
a_args->_aaArgs = newArgs;
a_args->_aaMaxArgs = newMax;
}
/*
* determine size of argument to add to list
*/
va_start(ap, a_format);
vres = vsnprintf(bfr, sizeof (bfr), a_format, ap);
va_end(ap);
/*
* use the expanded argument if it will fit in the built in buffer,
* otherwise, allocate space to hold the argument
*/
if (vres < sizeof (bfr)) {
/* duplicate text already generated in buffer */
rstr = _z_strdup(bfr);
} else {
/* allocate new space for argument to add */
rstr = (char *)_z_malloc(vres+2);
/* generate argument to add */
va_start(ap, a_format);
vres = vsnprintf(rstr, vres+1, a_format, ap);
va_end(ap);
}
/* add argument to the end of the argument array */
a_args->_aaArgs[a_args->_aaNumArgs++] = rstr;
a_args->_aaArgs[a_args->_aaNumArgs] = NULL;
/* successful - return */
return (B_TRUE);
}
/*
* Name: _z_free_args
* Description: free all storage contained in an argument array previously
* allocated by a call to _z_new_args
* Arguments: a_args - [RO, *RW] - (argArray_t *)
* Pointer to argument array (previously allocated via
* a call to _z_new_args) to free
* Returns: void
* NOTE: preserves errno (usually called right after e_execCmd*())
*/
void
_z_free_args(argArray_t *a_args)
{
int i;
int lerrno = errno;
/* entry assertions */
assert(a_args != NULL);
assert(a_args->_aaArgs != NULL);
/* free all arguments in the argument array */
for (i = (a_args->_aaNumArgs-1); i >= 0; i--) {
assert(a_args->_aaArgs[i] != NULL);
(void) free(a_args->_aaArgs[i]);
}
/* free argument array */
(void) free(a_args->_aaArgs);
/* free argument array structure */
(void) free(a_args);
/* restore errno */
errno = lerrno;
}
/*
* Name: _z_get_argc
* Description: return (int) argc count from argument array
* Arguments: a_args - [RO, *RW] - (argArray_t *)
* Pointer to argument array (previously allocated via
* a call to _z_new_args) to return argc count for
* Returns: int
* Count of the number of arguments in the argument array
* suitable for use in an exec*() call
*/
int
_z_get_argc(argArray_t *a_args)
{
return (a_args->_aaNumArgs);
}
/*
* Name: _z_get_argv
* Description: return (char **)argv pointer from argument array
* Arguments: a_args - [RO, *RW] - (argArray_t *)
* Pointer to argument array (previously allocated via
* a call to _z_new_args) to return argv pointer for
* Returns: char **
* Pointer to (char **)argv pointer suitable for use
* in an exec*() call
* NOTE: the actual character array is always terminated with a NULL
*/
char **
_z_get_argv(argArray_t *a_args)
{
return (a_args->_aaArgs);
}
/*
* Name: _z_new_args
* Description: create a new argument array for use in exec() calls
* Arguments: initialCount - [RO, *RO] - (int)
* Initial number of elements to populate the
* argument array with - use best guess
* Returns: argArray_t *
* Pointer to argument array that can be used in other
* functions that accept it as an argument
* == (argArray_t *)NULL - error
* NOTE: you must call _z_free_args() when the returned argument array is
* no longer needed so that all storage used can be freed up.
*/
argArray_t *
_z_new_args(int initialCount)
{
argArray_t *aa;
/* entry assertions */
assert(initialCount >= 0);
/* if no guess on size, then assume 1 */
if (initialCount == 0) {
initialCount = 1;
}
/* allocate new argument array structure */
aa = (argArray_t *)_z_calloc(sizeof (argArray_t));
/* allocate initial argument array */
aa->_aaArgs = (char **)_z_calloc((initialCount+1) * sizeof (char *));
/* initialize argument indexes */
aa->_aaNumArgs = 0;
aa->_aaMaxArgs = initialCount;
/* successful - return pointer to argument array created */
return (aa);
}