/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* url-util.c : utility functions to parse URLs */
/*
* This code is adapted form gzillaurl.c (http://www.gzilla.com)
* Copyright (C) Raph Levien <raph@acm.org>
*
* Modifications by Bertrand Guiheneuf <Bertrand.Guiheneuf@inria.fr>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*/
#include <ctype.h> /* for isalpha */
#include <stdlib.h> /* for atoi */
#include "url-util.h"
/**
* g_url_is_absolute:
* @url:
*
*
*
* Return value:
**/
gboolean
g_url_is_absolute (const char *url)
{
gint i;
for (i = 0; url[i] != '\0'; i++) {
if (url[i] == ':')
return TRUE;
else if (!isalpha (url[i]))
return FALSE;
}
return FALSE;
}
/**
* g_url_match_method:
* @url:
* @method:
*
*
*
* Return value: TRUE if the method matches
**/
gboolean
g_url_match_method (const char *url, const char *method)
{
gint i;
for (i = 0; method[i] != '\0'; i++)
if (url[i] != method[i]) return FALSE;
return (url[i] == ':');
}
/**
* g_url_add_slash:
* @url:
* @size_url:
*
* Add the trailing slash if necessary. Return FALSE if there isn't room
*
* Return value:
**/
gboolean
g_url_add_slash (char *url, gint size_url)
{
char hostname[256];
gint port;
char *tail;
if (g_url_match_method (url, "http") ||
g_url_match_method (url, "ftp")) {
tail = g_url_parse (url, hostname, sizeof(hostname), &port);
if (tail == NULL)
return TRUE;
if (tail[0] == '\0') {
if (strlen (url) + 1 == size_url)
return FALSE;
tail[0] = '/';
tail[1] = '\0';
}
}
return TRUE;
}
/**
* g_url_relative:
* @base_url:
* @relative_url:
* @new_url:
* @size_new_url:
*
*
*
* Return value:
**/
gboolean
g_url_relative (const char *base_url,
const char *relative_url,
char *new_url,
gint size_new_url)
{
gint i, j, k;
gint num_dotdot;
if (base_url == NULL || g_url_is_absolute (relative_url)) {
if (strlen (relative_url) >= size_new_url)
return FALSE;
strcpy (new_url, relative_url);
return g_url_add_slash (new_url, size_new_url);
}
/* Assure that we have enough room for at least the base URL. */
if (strlen (base_url) >= size_new_url)
return FALSE;
/* Copy http://hostname:port/ from base_url to new_url */
i = 0;
if (g_url_match_method (base_url, "http") ||
g_url_match_method (base_url, "ftp")) {
while (base_url[i] != '\0' && base_url[i] != ':')
new_url[i] = base_url[i++];
if (base_url[i] != '\0')
new_url[i] = base_url[i++];
if (base_url[i] != '\0')
new_url[i] = base_url[i++];
if (base_url[i] != '\0')
new_url[i] = base_url[i++];
while (base_url[i] != '\0' && base_url[i] != '/')
new_url[i] = base_url[i++];
} else {
while (base_url[i] != '\0' && base_url[i] != ':')
new_url[i] = base_url[i++];
if (base_url[i] != '\0')
new_url[i] = base_url[i++];
}
if (relative_url[0] == '/') {
if (i + strlen (relative_url) >= size_new_url)
return FALSE;
strcpy (new_url + i, relative_url);
return g_url_add_slash (new_url, size_new_url);
}
/* At this point, i points to the first slash following the hostname
(and port) in base_url. */
/* Now, figure how many ..'s to follow. */
num_dotdot = 0;
j = 0;
while (relative_url[j] != '\0') {
if (relative_url[j] == '.' &&
relative_url[j + 1] == '/') {
j += 2;
} else if (relative_url[j] == '.' &&
relative_url[j + 1] == '.' &&
relative_url[j + 2] == '/') {
j += 3;
num_dotdot++;
} else {
break;
}
}
/* Find num_dotdot+1 slashes back from the end, point k there. */
for (k = strlen (base_url); k > i && num_dotdot >= 0; k--)
if (base_url[k - 1] == '/')
num_dotdot--;
if (k + 1 + strlen (relative_url) - j >= size_new_url)
return FALSE;
while (i < k)
new_url[i] = base_url[i++];
if (relative_url[0] == '#')
while (base_url[i] != '\0')
new_url[i] = base_url[i++];
else if (base_url[i] == '/' || base_url[i] == '\0')
new_url[i++] = '/';
strcpy (new_url + i, relative_url + j);
return g_url_add_slash (new_url, size_new_url);
}
/* Parse the url, packing the hostname and port into the arguments, and
returning the suffix. Return NULL in case of failure. */
/**
* g_url_parse:
* @url:
* @hostname:
* @hostname_size:
* @port:
*
*
*
* Return value:
**/
char *
g_url_parse (char *url,
char *hostname,
gint hostname_size,
int *port)
{
gint i, j;
for (i = 0; url[i] != '\0' && url[i] != ':'; i++);
if (url[i] != ':' || url[i + 1] != '/' || url[i + 2] != '/') return NULL;
i += 3;
for (j = i; url[j] != '\0' && url[j] != ':' && url[j] != '/'; j++);
if (j - i >= hostname_size) return NULL;
memcpy (hostname, url + i, j - i);
hostname[j - i] = '\0';
if (url[j] == ':') {
*port = atoi (url + j + 1);
for (j++; url[j] != '\0' && url[j] != '/'; j++);
}
return url + j;
}
#ifndef UNIT_TEST
/* Parse "http://a/b#c" into "http://a/b" and "#c" (storing both as
newly allocated strings into *p_head and *p_tail, respectively.
Note: this routine allocates new strings for the subcomponents, so
that there's no arbitrary restriction on sizes. That's the way I want
all the URL functions to work eventually.
*/
void
g_url_parse_hash (char **p_head, char **p_tail, const char *url)
{
gint i;
/* todo: I haven't checked this for standards compliance. What's it
supposed to do when there are two hashes? */
for (i = 0; url[i] != '\0' && url[i] != '#'; i++);
*p_tail = g_strdup (url + i);
*p_head = g_new (char, i + 1);
memcpy (*p_head, url, i);
(*p_head)[i] = '\0';
}
#endif
#ifdef UNIT_TEST
/* Unit test as follows:
gcc -g -I/usr/local/include/gtk -DUNIT_TEST camelurl.c -o camelurl
./camelurl base_url relative_url
*/
int
main (int argc, char **argv)
{
char buf[80];
char hostname[80];
char *tail;
int port;
if (argc == 3) {
if (g_url_relative (argv[1], argv[2], buf, sizeof(buf))) {
printf ("%s\n", buf);
port = 80;
tail = g_url_parse (buf, hostname, sizeof (hostname), &port);
if (tail != NULL) {
printf ("hostname = %s, port = %d, tail = %s\n", hostname, port, tail);
}
} else {
printf ("buffer overflow!\n");
}
} else {
printf ("Usage: %s base_url relative_url\n", argv[0]);
}
return 0;
}
#endif
