utils.c

WSP is an HTTP to WSP proxy that can be used to forward HTTP requests to WSP, which is used in WAP 1

/*
Copyright (c) 2002-2003 Nicolas Jombart - HSC

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. The name of the author may not be used to endorse or promote products
   derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

/* $Id: utils.c,v 1.14 2004/09/09 11:25:21 jombart Exp $ */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include "wspp.h"

/*
 *  Display usage
 */
void usage(char *name) {
	printf("%s version %s: HTTP to WSP proxy.\n", name, WSPP_VERSION);
	printf("(c) 2003-2004 HSC\n");
	printf("\n");
	printf("Usage : %s <GW ADDR> <GW PORT> <LISTEN PORT>\n", name);
	printf("Default GW port is %d\n", DEFAULT_GW_PORT);
	printf("Default Listen port is %d\n", DEFAULT_LISTEN_PORT);
	printf("\n");
}

/*
 * Returns unsigned variable length integer
 * (null terminate the string)
 */
int uintvar(char *octets, int value) {

int i, j, c = 0;
char enc[6];

	/* No continue bit on the last one */
	enc[5] = value & 0x7f;
	value >>= 7;

	for(i = 4; i >= 0; i--) {
		enc[i] = 0x80 | (value & 0x7f);
		value >>= 7;
	}

	/* cancel 0x80 (==0) octets */
	for(i = 0; i < 6; i++) { if(enc[i] == '\x80') c++; }
	for(i = c, j = 0; i < 6; i++) { octets[j++] = enc[i]; }
	octets[j] = '\0'; /* null terminate */

	return(j);
}

int uintvar_len(int value) {

int i, j, c = 0;
char enc[6];
char octets[6];

	/* No continue bit on the last one */
	enc[5] = value & 0x7f;
	value >>= 7;

	for(i = 4; i >= 0; i--) {
		enc[i] = 0x80 | (value & 0x7f);
		value >>= 7;
	}

	/* cancel 0x80 (==0) octets */
	for(i = 0; i < 6; i++) { if(enc[i] == '\x80') c++; }
	for(i = c, j = 0; i < 6; i++) { octets[j++] = enc[i]; }
	octets[j] = '\0'; /* null terminate */
	return(strlen(octets));
}

/*
 *  Returns value from "Unsigned variable length integers"
 */
int from_uintvar (char *data, int offset, int max_offset)
{
	int value = 0;
	int octet;

	do
	{
		octet = data[offset];
		offset++;
		value <<= 7;
		value += octet & 0x7f;
	}
	while ((max_offset > offset) && (octet & 0x80));
	return value;
}

/*
 * strcat with realloc and make sure end by only one \n
 */
char * restrcat(char *s, const char *append)
{
	char *p;
	char *tmp;

	if(s == NULL) {
		if(append[strlen(append)-1] != '\n') { 
			tmp = (char *) malloc( (strlen(append) + 1) * sizeof(char));
			sprintf(tmp, "%s\n", append);
			s = strdup(tmp);
			free(tmp);
		}
		else {
			s = strdup(append);
		}
	} else {
		p = (char *) realloc(s, (strlen(append) + strlen(s) + 2) * sizeof(char));
		if(p == NULL)
			return(0);
		tmp = strdup(append);
		if(append[strlen(append)-1] == '\n') { 
			tmp[strlen(append) -1] = '\0';
		}
		strcat(p, tmp);
		free(tmp);
		strcat(p, "\n");
		s = p;
	}
	return(s);
}

/*
 * Fill an "Error 500" page
 */
void error500(http *body, int error_code) 
{
	char tmp[64];

	body->code = 500;
	body->headers = NULL;

	body->headers = restrcat(body->headers, HTTP_INTERNAL_ERROR);

	body->headers = restrcat(body->headers, "Content-type: text/html");
	body->headers = restrcat(body->headers, HEADER_VIA);

	body->data_length = strlen(INTERNAL_ERROR_BODY) + 16;
	body->data = malloc(body->data_length * sizeof(char));
	snprintf(body->data, body->data_length, INTERNAL_ERROR_BODY, error_code);

	/* correct length */
	body->data_length = strlen(body->data);
	sprintf(tmp, "Content-Length: %d", strlen(INTERNAL_ERROR_BODY));
	body->headers = restrcat(body->headers, tmp);

}

/*
 * Return encoded date as string
 */
char * extime(char *buffer, int size) {
int 	i;
size_t 	*epoch;
char 	*date;

	date = (char *) malloc(64);
	epoch = (int *) malloc(sizeof(size_t));
	*epoch = 0;

	for(i = 0; i < size; i++) {
		*epoch += buffer[i] & 0xFF;
		if(i < (size -1)) { *epoch <<= 8; }
	}

	date = ctime((const time_t *)epoch);
	return date;
}