Utility functions to parse URLs. Stolen shamelessly from gzilla

1999-04-23  bertrand <Bertrand.Guiheneuf@inria.fr>

	* camel/url-util.[ch]:
	Utility functions to parse URLs.
	Stolen shamelessly from gzilla (www.gzilla.com)
	written by Raph Levien <raph@acm.org>

	* camel/Makefile.am: added url-util.[ch]
	compilation.

svn path=/trunk/; revision=871

1 files changed, 326 insertions, 0 deletions

diff --git a/camel/url-util.c b/camel/url-util.c
new file mode 100644
index 0000000000..f4b769aad8
--- /dev/null
+++ b/camel/url-util.c
@@ -0,0 +1,326 @@
+/* -*- 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
+
+
+
+
+
+