attrib.c

uClinux上的ppp拨号驱动及测试程序

/*
 * Copyright 1997-2000 by Pawel Krawczyk <[e-mail]>
 *
 * See http://www.ceti.com.pl/~kravietz/progs/tacacs.html
 * for details.
 *
 * attrib.c  Procedures for handling internal list of attributes
 *			 for accounting and authorization functions. 
 */

#include <stdlib.h>
#include <string.h>
#include <syslog.h>

#include "tacplus.h"
#include "libtac.h"
#include "xalloc.h"

void tac_add_attrib(struct tac_attrib **attr, char *name, char *value) {
	struct tac_attrib *a;
	u_char l1 = (u_char) strlen(name);
	u_char l2 = (u_char) strlen(value);
	int total_len = l1 + l2 + 1; /* "name" + "=" + "value" */

	if(total_len > 255) {
			syslog(LOG_WARNING, "%s: attribute `%s' total length exceeds 255 characters, skipping", __FUNCTION__, name);
			return;
	}
	
	/* initialize the list if application passed us a null pointer */
	if(*attr == NULL) {
		*attr = (struct tac_attrib *) xcalloc(1, sizeof(struct tac_attrib));
		a = *attr;
	} else {
		/* find the last allocated block */
		a = *attr;
		while(a->next != NULL)
			a = a->next; /* a holds last allocated block */

		a->next = (struct tac_attrib *) xcalloc(1, sizeof(struct tac_attrib)); 
		a = a->next; /* set current block pointer to the new one */
	}

	/* fill the block */
	a->attr_len=total_len;
	a->attr = (char *) xcalloc(1, total_len);
	bcopy(name, a->attr, l1);         /* paste name */
	*(a->attr+l1)='='; 		          /* insert "=" */
	bcopy(value, (a->attr+l1+1), l2); /* paste value */

	a->next = NULL; /* make sure it's null */

}

void tac_free_attrib(struct tac_attrib **attr) {
	struct tac_attrib *a;
	struct tac_attrib *b;

	if(*attr == NULL)
			return;

	a  = b = *attr;
	
	/* find last allocated block */
	do {
			a = b;
			b = a->next;
			free(a->attr);
			free(a);
	} while (b != NULL);

}