[project @ 2004-08-09 16:11:58 by jmb]

Rework the interface of the URL handing module to allow for multiple error types.
Modify save_complete URL rewriting appropriately.

svn path=/import/netsurf/; revision=1206

16 files changed, 273 insertions, 197 deletions

diff --git a/content/fetch.c b/content/fetch.c
index 81f5e3a26..cb1353f98 100644
--- a/content/fetch.c
+++ b/content/fetch.c
@@ -227,12 +227,16 @@ struct fetch * fetch_start(char *url, char *referer,
 	CURLcode code;
 	CURLMcode codem;
 	struct curl_slist *slist;
+	url_func_result res;
 
 	fetch = malloc(sizeof (*fetch));
 	if (!fetch)
 		return 0;
 
-	host = url_host(url);
+	res = url_host(url, &host);
+	/* we only fail memory exhaustion */
+	if (res == URL_FUNC_NOMEM)
+		goto failed;
 
 	LOG(("fetch %p, url '%s'", fetch, url));
 
diff --git a/content/fetchcache.c b/content/fetchcache.c
index e22a8ae5b..02ce109b1 100644
--- a/content/fetchcache.c
+++ b/content/fetchcache.c
@@ -206,6 +206,7 @@ void fetchcache_callback(fetch_msg msg, void *p, const char *data,
 	char **params;
 	unsigned int i;
 	union content_msg_data msg_data;
+	url_func_result result;
 
 	switch (msg) {
 		case FETCH_TYPE:
@@ -283,8 +284,8 @@ void fetchcache_callback(fetch_msg msg, void *p, const char *data,
 			c->fetch = 0;
 			/* redirect URLs must be absolute by HTTP/1.1, but many sites send
 			 * relative ones: treat them as relative to requested URL */
-			url = url_join(data, c->url);
-			if (url) {
+			result = url_join(data, c->url, &url);
+			if (result == URL_FUNC_OK) {
 				msg_data.redirect = url;
 				content_broadcast(c, CONTENT_MSG_REDIRECT, msg_data);
 				free(url);
diff --git a/css/css.c b/css/css.c
index c4bbb8025..fa3f6f3bb 100644
--- a/css/css.c
+++ b/css/css.c
@@ -579,6 +579,7 @@ void css_atimport(struct content *c, struct css_node *node)
 	unsigned int i;
 	char **import_url;
 	struct content **import_content;
+	url_func_result res;
 
 	LOG(("@import rule"));
 
@@ -666,8 +667,8 @@ void css_atimport(struct content *c, struct css_node *node)
 		return;
 	}
 
-	url1 = url_join(url, c->url);
-	if (!url1) {
+	res = url_join(url, c->url, &url1);
+	if (res != URL_FUNC_OK) {
 		free(url);
 		return;
 	}
diff --git a/css/ruleset.c b/css/ruleset.c
index f0ab22d1c..90ca00226 100644
--- a/css/ruleset.c
+++ b/css/ruleset.c
@@ -621,6 +621,7 @@ bool parse_uri(const struct css_node *v, char **uri)
 	bool string = false;
 	const char *u;
 	char *t, *url;
+	url_func_result res;
 
 	switch (v->type) {
 		case CSS_NODE_URI:
@@ -650,11 +651,11 @@ bool parse_uri(const struct css_node *v, char **uri)
 			 * content is the parent HTML content
 			 */
 			if (v->stylesheet->type == CONTENT_HTML)
-				*uri = url_join(url, v->stylesheet->data.html.base_url);
+				res = url_join(url, v->stylesheet->data.html.base_url, uri);
 			else
-				*uri = url_join(url, v->stylesheet->url);
+				res = url_join(url, v->stylesheet->url, uri);
 			free(url);
-			if (!*uri)
+			if (res != URL_FUNC_OK)
 				return false;
 			break;
 		case CSS_NODE_STRING:
@@ -663,11 +664,11 @@ bool parse_uri(const struct css_node *v, char **uri)
 				return false;
 
 			if (v->stylesheet->type == CONTENT_HTML)
-				*uri = url_join(url, v->stylesheet->data.html.base_url);
+				res = url_join(url, v->stylesheet->data.html.base_url, uri);
 			else
-				*uri = url_join(url, v->stylesheet->url);
+				res = url_join(url, v->stylesheet->url, uri);
 			free(url);
-			if (!*uri)
+			if (res != URL_FUNC_OK)
 				return false;
 			break;
 		default:
diff --git a/desktop/browser.c b/desktop/browser.c
index 6e797a97e..36b6a9245 100644
--- a/desktop/browser.c
+++ b/desktop/browser.c
@@ -149,11 +149,12 @@ void browser_window_go_post(struct browser_window *bw, const char *url,
 	struct content *c;
 	char *url2;
 	char *hash;
+	url_func_result res;
 
 	LOG(("bw %p, url %s", bw, url));
 
-	url2 = url_normalize(url);
-	if (!url2) {
+	res = url_normalize(url, &url2);
+	if (res != URL_FUNC_OK) {
 		LOG(("failed to normalize url %s", url));
 		return;
 	}
@@ -602,6 +603,7 @@ void browser_window_mouse_click_html(struct browser_window *bw,
 	struct content *content = c;
 	struct content *gadget_content = c;
 	struct form_control *gadget = 0;
+	url_func_result res;
 
 	/* search the box tree for a link, imagemap, or form control */
 	while ((box = box_at_point(box, x, y, &box_x, &box_y, &content))) {
@@ -664,10 +666,10 @@ void browser_window_mouse_click_html(struct browser_window *bw,
 			/* drop through */
 		case GADGET_SUBMIT:
 			if (gadget->form) {
-				url = url_join(gadget->form->action, base_url);
+				res = url_join(gadget->form->action, base_url, &url);
 				snprintf(status_buffer, sizeof status_buffer,
 						messages_get("FormSubmit"),
-						url ? url :
+						(res == URL_FUNC_OK) ? url :
 						gadget->form->action);
 				status = status_buffer;
 				pointer = GUI_POINTER_POINT;
@@ -713,8 +715,8 @@ void browser_window_mouse_click_html(struct browser_window *bw,
 		}
 
 	} else if (href) {
-		url = url_join(href, base_url);
-		if (!url)
+		res = url_join(href, base_url, &url);
+		if (res != URL_FUNC_OK)
 			return;
 
 		if (title) {
@@ -1634,6 +1636,7 @@ void browser_form_submit(struct browser_window *bw, struct form *form,
 {
 	char *data = 0, *url = 0, *url1 = 0, *base;
 	struct form_successful_control *success;
+	url_func_result res;
 
 	assert(form);
 	assert(bw->current_content->type == CONTENT_HTML);
@@ -1659,8 +1662,8 @@ void browser_form_submit(struct browser_window *bw, struct form *form,
 			else {
 				sprintf(url, "%s?%s", form->action, data);
 			}
-			url1 = url_join(url, base);
-			if (!url1)
+			res = url_join(url, base, &url1);
+			if (res != URL_FUNC_OK)
 				break;
 			browser_window_go(bw, url1);
 			break;
@@ -1672,15 +1675,15 @@ void browser_form_submit(struct browser_window *bw, struct form *form,
 				warn_user("NoMemory", 0);
 				return;
 			}
-			url = url_join(form->action, base);
-			if (!url)
+			res = url_join(form->action, base, &url);
+			if (res != URL_FUNC_OK)
 				break;
 			browser_window_go_post(bw, url, data, 0, true);
 			break;
 
 		case method_POST_MULTIPART:
-			url = url_join(form->action, base);
-			if (!url)
+			res = url_join(form->action, base, &url);
+			if (res != URL_FUNC_OK)
 				break;
 			browser_window_go_post(bw, url, 0, success, true);
 			break;
diff --git a/desktop/loginlist.c b/desktop/loginlist.c
index 1baab81ac..3161bbd11 100644
--- a/desktop/loginlist.c
+++ b/desktop/loginlist.c
@@ -31,10 +31,13 @@ static struct login *loginlist = &login;
 void login_list_add(char *host, char* logindets) {
 
   struct login *nli = xcalloc(1, sizeof(*nli));
-  char *temp = url_host(host);
+  char *temp;
   char *i;
+  url_func_result res;
 
-  assert(temp);
+  res = url_host(host, &temp);
+
+  assert(res == URL_FUNC_OK);
 
   /* Go back to the path base ie strip the document name
    * eg. http://www.blah.com/blah/test.htm becomes
@@ -75,6 +78,7 @@ struct login *login_list_get(char *url) {
   char *temp, *host;
   char *i;
   int reached_scheme = 0;
+  url_func_result res;
 
   if (url == NULL)
     return NULL;
@@ -83,8 +87,8 @@ struct login *login_list_get(char *url) {
                         (strncasecmp(url, "https://", 8) != 0))
     return NULL;
 
-  host = url_host(url);
-  if (host == 0 || strlen(host) == 0) return NULL;
+  res = url_host(url, &host);
+  if (res != URL_FUNC_OK || strlen(host) == 0) return NULL;
 
   temp = xstrdup(url);
 
@@ -93,8 +97,8 @@ struct login *login_list_get(char *url) {
    */
   if (strlen(host) > strlen(temp)) {
     xfree(temp);
-    temp = url_host(url);
-    if (temp == 0 || strlen(temp) == 0) {
+    res = url_host(url, &temp);
+    if (res != URL_FUNC_OK || strlen(temp) == 0) {
       xfree(host);
       return NULL;
     }
diff --git a/render/box.c b/render/box.c
index 32d643fb5..5776501b0 100644
--- a/render/box.c
+++ b/render/box.c
@@ -640,6 +640,7 @@ struct css_style * box_get_style(struct content *c,
 	struct css_style style_new;
 	char * s;
 	unsigned int i;
+	url_func_result res;
 
 	memcpy(style, parent_style, sizeof(struct css_style));
 	memcpy(&style_new, &css_blank_style, sizeof(struct css_style));
@@ -658,12 +659,12 @@ struct css_style * box_get_style(struct content *c,
 	if ((s = (char *) xmlGetProp(n, (const xmlChar *) "background"))) {
 		style->background_image.type = CSS_BACKGROUND_IMAGE_URI;
 		/**\todo This will leak memory. */
-		style->background_image.uri = url_join(s, c->data.html.base_url);
+		res = url_join(s, c->data.html.base_url, &style->background_image.uri);
 		/* if url is equivalent to the parent's url,
 		 * we've got infinite inclusion. stop it here.
 		 * also bail if url_join failed.
 		 */
-		if (!style->background_image.uri ||
+		if (res != URL_FUNC_OK ||
 		    strcasecmp(style->background_image.uri, c->data.html.base_url) == 0)
 			style->background_image.type = CSS_BACKGROUND_IMAGE_NONE;
 		xmlFree(s);
@@ -897,6 +898,7 @@ struct box_result box_image(xmlNode *n, struct box_status *status,
 	struct box *box;
 	char *s, *url, *s1, *map;
 	xmlChar *s2;
+	url_func_result res;
 
 	box = box_create(style, status->href, status->title, status->id,
 			status->content->data.html.box_pool);
@@ -926,12 +928,12 @@ struct box_result box_image(xmlNode *n, struct box_status *status,
 
 	/* remove leading and trailing whitespace */
 	s1 = strip(s);
-	url = url_join(s1, status->content->data.html.base_url);
+	res = url_join(s1, status->content->data.html.base_url, &url);
 	/* if url is equivalent to the parent's url,
 	 * we've got infinite inclusion. stop it here.
 	 * also bail if url_join failed.
 	 */
-	if (!url ||
+	if (res != URL_FUNC_OK ||
 	    strcasecmp(url, status->content->data.html.base_url) == 0) {
 		xmlFree(s);
 		return (struct box_result) {box, false, false};
@@ -1224,6 +1226,7 @@ struct box_result box_input(xmlNode *n, struct box_status *status,
 	struct box* box = NULL;
 	struct form_control *gadget = NULL;
 	char *s, *type, *url;
+	url_func_result res;
 
 	type = (char *) xmlGetProp(n, (const xmlChar *) "type");
 
@@ -1356,12 +1359,13 @@ struct box_result box_input(xmlNode *n, struct box_status *status,
 		gadget->box = box;
 		gadget->type = GADGET_IMAGE;
 		if ((s = (char *) xmlGetProp(n, (const xmlChar*) "src"))) {
-			url = url_join(s, status->content->data.html.base_url);
+			res = url_join(s, status->content->data.html.base_url, &url);
 			/* if url is equivalent to the parent's url,
 			 * we've got infinite inclusion. stop it here.
 			 * also bail if url_join failed.
 			 */
-			if (url && strcasecmp(url, status->content->data.html.base_url) != 0)
+			if (res == URL_FUNC_OK &&
+					strcasecmp(url, status->content->data.html.base_url) != 0)
 				html_fetch_object(status->content, url, box,
 						image_types,
 						status->content->available_width,
@@ -2049,6 +2053,7 @@ struct box_result box_object(xmlNode *n, struct box_status *status,
 	struct plugin_params* pp;
 	char *s, *url = NULL, *map;
 	xmlNode *c;
+	url_func_result res;
 
 	box = box_create(style, status->href, 0, status->id,
 			status->content->data.html.box_pool);
@@ -2065,12 +2070,12 @@ struct box_result box_object(xmlNode *n, struct box_status *status,
 
         /* object data */
 	if ((s = (char *) xmlGetProp(n, (const xmlChar *) "data"))) {
-		url = url_join(s, status->content->data.html.base_url);
+		res = url_join(s, status->content->data.html.base_url, &url);
 		/* if url is equivalent to the parent's url,
 		 * we've got infinite inclusion. stop it here.
 		 * also bail if url_join failed.
 		 */
-		if (!url || strcasecmp(url, status->content->data.html.base_url) == 0) {
+		if (res != URL_FUNC_OK || strcasecmp(url, status->content->data.html.base_url) == 0) {
 			free(po);
 			xmlFree(s);
 			return (struct box_result) {box, true, true};
@@ -2193,6 +2198,7 @@ struct box_result box_embed(xmlNode *n, struct box_status *status,
 	struct plugin_params *pp;
 	char *s, *url = NULL;
 	xmlAttr *a;
+	url_func_result res;
 
 	box = box_create(style, status->href, 0, status->id,
 			status->content->data.html.box_pool);
@@ -2209,12 +2215,12 @@ struct box_result box_embed(xmlNode *n, struct box_status *status,
 
 	/* embed src */
 	if ((s = (char *) xmlGetProp(n, (const xmlChar *) "src"))) {
-		url = url_join(s, status->content->data.html.base_url);
+		res = url_join(s, status->content->data.html.base_url, &url);
 		/* if url is equivalent to the parent's url,
 		 * we've got infinite inclusion. stop it here.
 		 * also bail if url_join failed.
 		 */
-		if (!url || strcasecmp(url, status->content->data.html.base_url) == 0) {
+		if (res != URL_FUNC_OK || strcasecmp(url, status->content->data.html.base_url) == 0) {
 			free(po);
 			xmlFree(s);
 			return (struct box_result) {box, false, true};
@@ -2268,6 +2274,7 @@ struct box_result box_applet(xmlNode *n, struct box_status *status,
 	struct plugin_params *pp;
 	char *s, *url = NULL;
 	xmlNode *c;
+	url_func_result res;
 
 	box = box_create(style, status->href, 0, status->id,
 			status->content->data.html.box_pool);
@@ -2284,12 +2291,12 @@ struct box_result box_applet(xmlNode *n, struct box_status *status,
 
 	/* code */
 	if ((s = (char *) xmlGetProp(n, (const xmlChar *) "code"))) {
-		url = url_join(s, status->content->data.html.base_url);
+		res = url_join(s, status->content->data.html.base_url, &url);
 		/* if url is equivalent to the parent's url,
 		 * we've got infinite inclusion. stop it here.
 		 * also bail if url_join failed.
 		 */
-		if (!url || strcasecmp(url, status->content->data.html.base_url) == 0) {
+		if (res != URL_FUNC_OK || strcasecmp(url, status->content->data.html.base_url) == 0) {
 			free(po);
 			xmlFree(s);
 			return (struct box_result) {box, true, false};
@@ -2376,6 +2383,7 @@ struct box_result box_iframe(xmlNode *n, struct box_status *status,
         struct box *box;
 	struct object_params *po;
 	char *s, *url = NULL;
+	url_func_result res;
 
 	box = box_create(style, status->href, 0, status->id,
 			status->content->data.html.box_pool);
@@ -2392,12 +2400,12 @@ struct box_result box_iframe(xmlNode *n, struct box_status *status,
 
 	/* iframe src */
 	if ((s = (char *) xmlGetProp(n, (const xmlChar *) "src"))) {
-		url = url_join(s, status->content->data.html.base_url);
+		res = url_join(s, status->content->data.html.base_url, &url);
 		/* if url is equivalent to the parent's url,
 		 * we've got infinite inclusion. stop it here.
 		 * also bail if url_join failed.
 		 */
-		if (!url || strcasecmp(url, status->content->data.html.base_url) == 0) {
+		if (res != URL_FUNC_OK || strcasecmp(url, status->content->data.html.base_url) == 0) {
 			free(po);
 			xmlFree(s);
 			return (struct box_result) {box, false, true};
@@ -2430,16 +2438,17 @@ bool plugin_decode(struct content* content, char* url, struct box* box,
                   struct object_params* po)
 {
   struct plugin_params * pp;
+  url_func_result res;
 
   /* Check if the codebase attribute is defined.
    * If it is not, set it to the codebase of the current document.
    */
    if(po->codebase == 0)
-           po->codebase = url_join("./", content->data.html.base_url);
+           res = url_join("./", content->data.html.base_url, &po->codebase);
    else
-           po->codebase = url_join(po->codebase, content->data.html.base_url);
+           res = url_join(po->codebase, content->data.html.base_url, &po->codebase);
 
-  if (!po->codebase)
+  if (res != URL_FUNC_OK)
     return false;
 
   /* Set basehref */
@@ -2464,13 +2473,14 @@ bool plugin_decode(struct content* content, char* url, struct box* box,
                                pp = pp->next);
                            if(pp == 0)
                            	   return false;
-                           url = url_join(pp->value, po->basehref);
-                           if (!url)
+                           res = url_join(pp->value, po->basehref, &url);
+                           if (res != URL_FUNC_OK)
                            	   return false;
                            /* munge the codebase */
-                           po->codebase = url_join("./",
-					   content->data.html.base_url);
-                           if (!po->codebase)
+                           res = url_join("./",
+					   content->data.html.base_url,
+					   &po->codebase);
+                           if (res != URL_FUNC_OK)
                            	   return false;
                    }
                    else {
@@ -2479,8 +2489,8 @@ bool plugin_decode(struct content* content, char* url, struct box* box,
                    }
            }
            else {
-                   url = url_join(po->classid, po->codebase);
-                   if (!url)
+                   res = url_join(po->classid, po->codebase, &url);
+                   if (res != URL_FUNC_OK)
                    	   return false;
 
                    /* The java plugin doesn't need the .class extension
@@ -2492,8 +2502,8 @@ bool plugin_decode(struct content* content, char* url, struct box* box,
            }
    }
    else {
-           url = url_join(po->data, po->codebase);
-           if (!url)
+           res = url_join(po->data, po->codebase, &url);
+           if (res != URL_FUNC_OK)
            	return false;
    }
 
@@ -2537,6 +2547,7 @@ struct box_result box_frameset(xmlNode *n, struct box_status *status,
 	struct box_result r;
 	struct box_multi_length *row_height = 0, *col_width = 0;
 	xmlNode *c;
+	url_func_result res;
 
 	box = box_create(style, 0, status->title, status->id,
 			status->content->data.html.box_pool);
@@ -2676,12 +2687,12 @@ struct box_result box_frameset(xmlNode *n, struct box_status *status,
 			}
 
 			s1 = strip(s);
-			url = url_join(s1, status->content->data.html.base_url);
+			res = url_join(s1, status->content->data.html.base_url, &url);
 			/* if url is equivalent to the parent's url,
 			 * we've got infinite inclusion. stop it here.
 			 * also bail if url_join failed.
 			 */
-			if (!url || strcasecmp(url, status->content->data.html.base_url) == 0) {
+			if (res != URL_FUNC_OK || strcasecmp(url, status->content->data.html.base_url) == 0) {
 				xmlFree(s);
 				c = c->next;
 				continue;
diff --git a/render/html.c b/render/html.c
index 7bda3b02a..b19e99c30 100644
--- a/render/html.c
+++ b/render/html.c
@@ -304,8 +304,10 @@ void html_head(struct content *c, xmlNode *head)
 		} else if (strcmp(node->name, "base") == 0) {
 			char *href = (char *) xmlGetProp(node, (const xmlChar *) "href");
 			if (href) {
-				char *url = url_normalize(href);
-				if (url) {
+				char *url;
+				url_func_result res;
+				res = url_normalize(href, &url);
+				if (res == URL_FUNC_OK) {
 					free(c->data.html.base_url);
 					c->data.html.base_url = url;
 				}
@@ -330,6 +332,7 @@ void html_find_stylesheets(struct content *c, xmlNode *head)
 	unsigned int i = STYLESHEET_START;
 	unsigned int last_active = 0;
 	union content_msg_data msg_data;
+	url_func_result res;
 
 	/* stylesheet 0 is the base style sheet,
 	 * stylesheet 1 is the adblocking stylesheet,
@@ -414,9 +417,9 @@ void html_find_stylesheets(struct content *c, xmlNode *head)
 			/* TODO: only the first preferred stylesheets (ie. those with a
 			 * title attribute) should be loaded (see HTML4 14.3) */
 
-			url = url_join(href, c->data.html.base_url);
+			res = url_join(href, c->data.html.base_url, &url);
 			xmlFree(href);
-			if (!url)
+			if (res != URL_FUNC_OK)
 				continue;
 
 			LOG(("linked stylesheet %i '%s'", i, url));
diff --git a/riscos/401login.c b/riscos/401login.c
index 8beaac9be..9edef15a8 100644
--- a/riscos/401login.c
+++ b/riscos/401login.c
@@ -46,10 +46,11 @@ void ro_gui_401login_init(void)
 void gui_401login_open(struct browser_window *bw, struct content *c, char *realm)
 {
 	char *murl, *host;
+	url_func_result res;
 
 	murl = c->url;
-	host = url_host(murl);
-	assert(host);
+	res = url_host(murl, &host);
+	assert(res == URL_FUNC_OK);
 	bwin = bw;
 
 	ro_gui_401login_open(bw->window->window, host, realm, murl);
diff --git a/riscos/download.c b/riscos/download.c
index 2a6d8d583..77aa9a217 100644
--- a/riscos/download.c
+++ b/riscos/download.c
@@ -128,6 +128,7 @@ struct gui_download_window *gui_download_window_create(const char *url,
 	char temp_name[40];
 	struct gui_download_window *dw;
 	os_error *error;
+	url_func_result res;
 
 	dw = malloc(sizeof *dw);
 	if (!dw) {
@@ -188,7 +189,7 @@ struct gui_download_window *gui_download_window_create(const char *url,
 			(osspriteop_id) dw->sprite_name;
 
 	strcpy(dw->path, messages_get("SaveObject"));
-	if ((nice = url_nice(url))) {
+	if ((res = url_nice(url, &nice)) == URL_FUNC_OK) {
 		strcpy(dw->path, nice);
 		free(nice);
 	}
diff --git a/riscos/hotlist.c b/riscos/hotlist.c
index 8a2a57100..de91fbad7 100644
--- a/riscos/hotlist.c
+++ b/riscos/hotlist.c
@@ -906,6 +906,7 @@ struct hotlist_entry *ro_gui_hotlist_create_entry(const char *title,
 		const char *url, int filetype,
 		struct hotlist_entry *folder) {
 	struct hotlist_entry *entry;
+	url_func_result res;
 
 	/*	Check we have a title or a URL
 	*/
@@ -923,7 +924,8 @@ struct hotlist_entry *ro_gui_hotlist_create_entry(const char *title,
 		use the URL instead
 	*/
 	entry->url = 0;
-	if ((url) && ((entry->url = url_normalize(url)) == 0)) {
+	if ((url) && ((res = url_normalize(url, &entry->url)) != URL_FUNC_OK)) {
+		/** \todo use correct error message */
 		warn_user("NoMemory", 0);
 		free(entry->url);
 		free(entry);
@@ -2443,6 +2445,7 @@ void ro_gui_hotlist_dialog_click(wimp_pointer *pointer) {
 	int close_icon, ok_icon;
 	bool folder;
 	bool add;
+	url_func_result res;
 
 	/*	Get our data
 	*/
@@ -2502,8 +2505,9 @@ void ro_gui_hotlist_dialog_click(wimp_pointer *pointer) {
 		if (entry == NULL) return;
 		if (url) {
 			old_value = entry->url;
-			entry->url = url_normalize(url);
-			if (!entry->url) {
+			res = url_normalize(url, &entry->url);
+			if (res != URL_FUNC_OK) {
+				/** \todo use correct error message */
 				warn_user("NoMemory", 0);
 				entry->url = old_value;
 				return;
diff --git a/riscos/save.c b/riscos/save.c
index 14564f727..b73f57a8d 100644
--- a/riscos/save.c
+++ b/riscos/save.c
@@ -84,6 +84,7 @@ void ro_gui_save_open(gui_save_type save_type, struct content *c,
 	const char *name = "";
 	const char *nice;
 	os_error *error;
+	url_func_result res;
 
 	assert(save_type == GUI_SAVE_HOTLIST_EXPORT_HTML || c);
 
@@ -102,7 +103,7 @@ void ro_gui_save_open(gui_save_type save_type, struct content *c,
 	/* filename */
 	name = gui_save_table[save_type].name;
 	if (c) {
-		if ((nice = url_nice(c->url)))
+		if ((res = url_nice(c->url, &nice)) == URL_FUNC_OK)
 			name = nice;
         }
 	ro_gui_set_icon_string(dialog_saveas, ICON_SAVE_PATH, name);
diff --git a/riscos/save_complete.c b/riscos/save_complete.c
index fad990c20..519181188 100644
--- a/riscos/save_complete.c
+++ b/riscos/save_complete.c
@@ -342,6 +342,7 @@ char * rewrite_stylesheet_urls(const char *source, unsigned int size,
 	unsigned int i;
 	unsigned int imports = 0;
 	regmatch_t match[11];
+	url_func_result result;
 
 	/* count number occurences of @import to (over)estimate result size */
 	/* can't use strstr because source is not 0-terminated string */
@@ -399,9 +400,9 @@ char * rewrite_stylesheet_urls(const char *source, unsigned int size,
 			free(res);
 			return 0;
 		}
-		url = url_join(url2, base);
+		result = url_join(url2, base, (char**)&url);
 		free(url2);
-		if (!url) {
+		if (result == URL_FUNC_NOMEM) {
 			free(res);
 			return 0;
 		}
@@ -410,17 +411,25 @@ char * rewrite_stylesheet_urls(const char *source, unsigned int size,
 		memcpy(res + *osize, source + offset, match[0].rm_so);
 		*osize += match[0].rm_so;
 
-		content = save_complete_list_find(url);
-		if (content) {
-			/* replace import */
-			snprintf(buf, sizeof buf, "@import '%x'",
-					(unsigned int) content);
-			memcpy(res + *osize, buf, strlen(buf));
-			*osize += strlen(buf);
-		} else {
+		if (result == URL_FUNC_OK) {
+			content = save_complete_list_find(url);
+			if (content) {
+				/* replace import */
+				snprintf(buf, sizeof buf, "@import '%x'",
+						(unsigned int) content);
+				memcpy(res + *osize, buf, strlen(buf));
+				*osize += strlen(buf);
+			} else {
+				/* copy import */
+				memcpy(res + *osize, source + offset + match[0].rm_so,
+					match[0].rm_eo - match[0].rm_so);
+				*osize += match[0].rm_eo - match[0].rm_so;
+			}
+		}
+		else {
 			/* copy import */
 			memcpy(res + *osize, source + offset + match[0].rm_so,
-					match[0].rm_eo - match[0].rm_so);
+				match[0].rm_eo - match[0].rm_so);
 			*osize += match[0].rm_eo - match[0].rm_so;
 		}
 
@@ -570,6 +579,7 @@ bool rewrite_url(xmlNode *n, const char *attr, const char *base)
 	char *url, *data;
 	char rel[20];
 	struct content *content;
+	url_func_result res;
 
 	if (!xmlHasProp(n, (const xmlChar *) attr))
 		return true;
@@ -578,25 +588,29 @@ bool rewrite_url(xmlNode *n, const char *attr, const char *base)
 	if (!data)
 		return false;
 
-	url = url_join(data, base);
+	res = url_join(data, base, &url);
 	xmlFree(data);
-	if (!url)
+	if (res == URL_FUNC_NOMEM)
 		return false;
-
-	content = save_complete_list_find(url);
-	if (content) {
-		/* found a match */
-		free(url);
-		snprintf(rel, sizeof rel, "%x", (unsigned int) content);
-		if (!xmlSetProp(n, (const xmlChar *) attr, (xmlChar *) rel))
-			return false;
-	} else {
-		/* no match found */
-		if (!xmlSetProp(n, (const xmlChar *) attr, (xmlChar *) url)) {
+	else if (res == URL_FUNC_OK) {
+		content = save_complete_list_find(url);
+		if (content) {
+			/* found a match */
+			free(url);
+			snprintf(rel, sizeof rel, "%x",
+						(unsigned int) content);
+			if (!xmlSetProp(n, (const xmlChar *) attr,
+							(xmlChar *) rel))
+				return false;
+		} else {
+			/* no match found */
+			if (!xmlSetProp(n, (const xmlChar *) attr,
+							(xmlChar *) url)) {
+				free(url);
+				return false;
+			}
 			free(url);
-			return false;
 		}
-		free(url);
 	}
 
 	return true;
diff --git a/riscos/window.c b/riscos/window.c
index ab945cb0d..a0715738d 100644
--- a/riscos/window.c
+++ b/riscos/window.c
@@ -1235,6 +1235,7 @@ bool ro_gui_window_keypress(struct gui_window *g, int key, bool toolbar)
 	char *url;
 	os_error *error;
 	wimp_pointer pointer;
+	url_func_result res;
 
 	error = xwimp_get_pointer_info(&pointer);
 	if (error) {
@@ -1361,8 +1362,8 @@ bool ro_gui_window_keypress(struct gui_window *g, int key, bool toolbar)
 		case wimp_KEY_RETURN:
 			if (!toolbar)
 				break;
-			url = url_normalize(g->url);
-			if (url) {
+			res = url_normalize(g->url, &url);
+			if (res == URL_FUNC_OK) {
 				gui_window_set_url(g, url);
 				browser_window_go(g->bw, url);
 				free(url);
diff --git a/utils/url.c b/utils/url.c
index 09c2816bf..b1da7ce28 100644
--- a/utils/url.c
+++ b/utils/url.c
@@ -57,20 +57,21 @@ void url_init(void)
  * replaced with "/". Characters are unescaped if safe.
  */
 
-char *url_normalize(const char *url)
+url_func_result url_normalize(const char *url, char **result)
 {
 	char c;
-	char *res = 0;
 	int m;
 	int i;
 	int len;
 	bool http = false;
 	regmatch_t match[10];
 
+	(*result) = 0;
+
 	m = regexec(&url_re, url, 10, match, 0);
 	if (m) {
 		LOG(("url '%s' failed to match regex", url));
-		return 0;
+		return URL_FUNC_FAILED;
 	}
 
 	len = strlen(url);
@@ -78,27 +79,27 @@ char *url_normalize(const char *url)
 	if (match[1].rm_so == -1) {
 		/* scheme missing: add http:// and reparse */
 		LOG(("scheme missing: using http"));
-		res = malloc(strlen(url) + 13);
-		if (!res) {
+		(*result) = malloc(strlen(url) + 13);
+		if (!(*result)) {
 			LOG(("malloc failed"));
-			return 0;
+			return URL_FUNC_NOMEM;
 		}
-		strcpy(res, "http://");
-		strcpy(res + 7, url);
-		m = regexec(&url_re, res, 10, match, 0);
+		strcpy((*result), "http://");
+		strcpy((*result) + 7, url);
+		m = regexec(&url_re, (*result), 10, match, 0);
 		if (m) {
-			LOG(("url '%s' failed to match regex", res));
-			free(res);
-			return 0;
+			LOG(("url '%s' failed to match regex", (*result)));
+			free((*result));
+			return URL_FUNC_FAILED;
 		}
 		len += 7;
 	} else {
-		res = malloc(len + 6);
-		if (!res) {
+		(*result) = malloc(len + 6);
+		if (!(*result)) {
 			LOG(("strdup failed"));
-			return 0;
+			return URL_FUNC_FAILED;
 		}
-		strcpy(res, url);
+		strcpy((*result), url);
 	}
 
 	/*for (unsigned int i = 0; i != 10; i++) {
@@ -113,55 +114,59 @@ char *url_normalize(const char *url)
 	/* make scheme lower-case */
 	if (match[2].rm_so != -1) {
 		for (i = match[2].rm_so; i != match[2].rm_eo; i++)
-			res[i] = tolower(res[i]);
-		if (match[2].rm_eo == 4 && res[0] == 'h' && res[1] == 't' &&
-				res[2] == 't' && res[3] == 'p')
+			(*result)[i] = tolower((*result)[i]);
+		if (match[2].rm_eo == 4 && (*result)[0] == 'h' &&
+				(*result)[1] == 't' && (*result)[2] == 't' &&
+				(*result)[3] == 'p')
 			http = true;
 	}
 
 	/* make empty path into "/" */
 	if (match[5].rm_so != -1 && match[5].rm_so == match[5].rm_eo) {
-		memmove(res + match[5].rm_so + 1, res + match[5].rm_so,
+		memmove((*result) + match[5].rm_so + 1,
+				(*result) + match[5].rm_so,
 				len - match[5].rm_so + 1);
-		res[match[5].rm_so] = '/';
+		(*result)[match[5].rm_so] = '/';
 		len++;
 	}
 
 	/* make host lower-case */
 	if (match[4].rm_so != -1) {
 		for (i = match[4].rm_so; i != match[4].rm_eo; i++) {
-			if (res[i] == ':') {
-				if (http && res[i + 1] == '8' &&
-						res[i + 2] == '0' &&
+			if ((*result)[i] == ':') {
+				if (http && (*result)[i + 1] == '8' &&
+						(*result)[i + 2] == '0' &&
 						i + 3 == match[4].rm_eo) {
-					memmove(res + i, res + i + 3,
+					memmove((*result) + i,
+							(*result) + i + 3,
 							len - match[4].rm_eo);
 					len -= 3;
-					res[len] = '\0';
+					(*result)[len] = '\0';
 				} else if (i + 1 == match[4].rm_eo) {
-					memmove(res + i, res + i + 1,
+					memmove((*result) + i,
+							(*result) + i + 1,
 							len - match[4].rm_eo);
 					len--;
-					res[len] = '\0';
+					(*result)[len] = '\0';
 				}
 				break;
 			}
-			res[i] = tolower(res[i]);
+			(*result)[i] = tolower((*result)[i]);
 		}
 	}
 
 	/* unescape non-"reserved" escaped characters */
 	for (i = 0; i != len; i++) {
-		if (res[i] != '%')
+		if ((*result)[i] != '%')
 			continue;
-		c = tolower(res[i + 1]);
+		c = tolower((*result)[i + 1]);
 		if ('0' <= c && c <= '9')
 			m = 16 * (c - '0');
 		else if ('a' <= c && c <= 'f')
 			m = 16 * (c - 'a' + 10);
 		else
 			continue;
-		c = tolower(res[i + 2]);
+		c = tolower((*result)[i + 2]);
 		if ('0' <= c && c <= '9')
 			m += c - '0';
 		else if ('a' <= c && c <= 'f')
@@ -175,12 +180,12 @@ char *url_normalize(const char *url)
 			continue;
 		}
 
-		res[i] = m;
-		memmove(res + i + 1, res + i + 3, len - i - 2);
+		(*result)[i] = m;
+		memmove((*result) + i + 1, (*result) + i + 3, len - i - 2);
 		len -= 2;
 	}
 
-	return res;
+	return URL_FUNC_OK;
 }
 
 
@@ -192,12 +197,11 @@ char *url_normalize(const char *url)
  * \return  an absolute URL, allocated on the heap, or 0 on failure
  */
 
-char *url_join(const char *rel, const char *base)
+url_func_result url_join(const char *rel, const char *base, char **result)
 {
 	int m;
 	int i, j;
 	char *buf = 0;
-	char *res;
 	const char *scheme = 0, *authority = 0, *path = 0, *query = 0,
 			*fragment = 0;
 	int scheme_len = 0, authority_len = 0, path_len = 0, query_len = 0,
@@ -206,11 +210,13 @@ char *url_join(const char *rel, const char *base)
 	regmatch_t rel_match[10];
 	regmatch_t up_match[3];
 
+	(*result) = 0;
+
 	/* see RFC 2396 section 5.2 */
 	m = regexec(&url_re, base, 10, base_match, 0);
 	if (m) {
 		LOG(("base url '%s' failed to match regex", base));
-		return 0;
+		return URL_FUNC_FAILED;
 	}
 	/*for (unsigned int i = 0; i != 10; i++) {
 		if (base_match[i].rm_so == -1)
@@ -221,7 +227,7 @@ char *url_join(const char *rel, const char *base)
 	}*/
 	if (base_match[2].rm_so == -1) {
 		LOG(("base url '%s' is not absolute", base));
-		return 0;
+		return URL_FUNC_FAILED;
 	}
 	scheme = base + base_match[2].rm_so;
 	scheme_len = base_match[2].rm_eo - base_match[2].rm_so;
@@ -236,7 +242,7 @@ char *url_join(const char *rel, const char *base)
 	m = regexec(&url_re, rel, 10, rel_match, 0);
 	if (m) {
 		LOG(("relative url '%s' failed to match regex", rel));
-		return 0;
+		return URL_FUNC_FAILED;
 	}
 
 	/* 2) */
@@ -292,7 +298,7 @@ char *url_join(const char *rel, const char *base)
 	buf = malloc(path_len + rel_match[5].rm_eo + 10);
 	if (!buf) {
 		LOG(("malloc failed"));
-		return 0;
+		return URL_FUNC_NOMEM;
 	}
 	/* a) */
 	strncpy(buf, path, path_len);
@@ -334,44 +340,44 @@ char *url_join(const char *rel, const char *base)
         path = buf;
 
 step7:	/* 7) */
-	res = malloc(scheme_len + 1 + 2 + authority_len + path_len + 1 + 1 +
+	(*result) = malloc(scheme_len + 1 + 2 + authority_len + path_len + 1 + 1 +
 			query_len + 1 + fragment_len + 1);
-	if (!res) {
+	if (!(*result)) {
 		LOG(("malloc failed"));
 		free(buf);
-		return 0;
+		return URL_FUNC_NOMEM;
 	}
 
-	strncpy(res, scheme, scheme_len);
-	res[scheme_len] = ':';
+	strncpy((*result), scheme, scheme_len);
+	(*result)[scheme_len] = ':';
 	i = scheme_len + 1;
 	if (authority) {
-		res[i++] = '/';
-		res[i++] = '/';
-		strncpy(res + i, authority, authority_len);
+		(*result)[i++] = '/';
+		(*result)[i++] = '/';
+		strncpy((*result) + i, authority, authority_len);
 		i += authority_len;
 	}
 	if (path_len) {
-		strncpy(res + i, path, path_len);
+		strncpy((*result) + i, path, path_len);
 		i += path_len;
 	} else {
-		res[i++] = '/';
+		(*result)[i++] = '/';
 	}
 	if (query) {
-		res[i++] = '?';
-		strncpy(res + i, query, query_len);
+		(*result)[i++] = '?';
+		strncpy((*result) + i, query, query_len);
 		i += query_len;
 	}
 	if (fragment) {
-		res[i++] = '#';
-		strncpy(res + i, fragment, fragment_len);
+		(*result)[i++] = '#';
+		strncpy((*result) + i, fragment, fragment_len);
 		i += fragment_len;
 	}
-	res[i] = 0;
+	(*result)[i] = 0;
 
 	free(buf);
 
-	return res;
+	return URL_FUNC_OK;
 }
 
 
@@ -382,29 +388,30 @@ step7:	/* 7) */
  * \returns  host name allocated on heap, or 0 on failure
  */
 
-char *url_host(const char *url)
+url_func_result url_host(const char *url, char **result)
 {
 	int m;
-	char *host;
 	regmatch_t match[10];
 
+	(*result) = 0;
+
 	m = regexec(&url_re, url, 10, match, 0);
 	if (m) {
 		LOG(("url '%s' failed to match regex", url));
-		return 0;
+		return URL_FUNC_FAILED;
 	}
 	if (match[4].rm_so == -1)
-		return 0;
+		return URL_FUNC_FAILED;
 
-	host = malloc(match[4].rm_eo - match[4].rm_so + 1);
-	if (!host) {
+	(*result) = malloc(match[4].rm_eo - match[4].rm_so + 1);
+	if (!(*result)) {
 		LOG(("malloc failed"));
-		return 0;
+		return URL_FUNC_NOMEM;
 	}
-	strncpy(host, url + match[4].rm_so, match[4].rm_eo - match[4].rm_so);
-	host[match[4].rm_eo - match[4].rm_so] = 0;
+	strncpy((*result), url + match[4].rm_so, match[4].rm_eo - match[4].rm_so);
+	(*result)[match[4].rm_eo - match[4].rm_so] = 0;
 
-	return host;
+	return URL_FUNC_OK;
 }
 
 
@@ -415,27 +422,29 @@ char *url_host(const char *url)
  * \returns  filename allocated on heap, or 0 on memory exhaustion
  */
 
-char *url_nice(const char *url)
+url_func_result url_nice(const char *url, char **result)
 {
 	unsigned int i, j, k = 0, so;
 	unsigned int len;
 	const char *colon;
 	char buf[40];
-	char *result;
 	char *rurl;
 	int m;
 	regmatch_t match[10];
 
-	result = malloc(40);
-	if (!result)
-		return 0;
+	/* just in case */
+	(*result) = 0;
+
+	(*result) = malloc(40);
+	if (!(*result))
+		return URL_FUNC_NOMEM;
 
 	len = strlen(url);
 	assert(len != 0);
 	rurl = malloc(len + 1);
 	if (!rurl) {
-		free(result);
-		return 0;
+		free((*result));
+		return URL_FUNC_NOMEM;
 	}
 
 	/* reverse url into rurl */
@@ -447,11 +456,11 @@ char *url_nice(const char *url)
 	colon = strchr(url, ':');
 	if (colon)
 		url = colon + 1;
-	strncpy(result, url, 15);
-	result[15] = 0;
-	for (i = 0; result[i]; i++)
-		if (!isalnum(result[i]))
-			result[i] = '_';
+	strncpy((*result), url, 15);
+	(*result)[15] = 0;
+	for (i = 0; (*result)[i]; i++)
+		if (!isalnum((*result)[i]))
+			(*result)[i] = '_';
 
 	/* append nice pieces */
 	j = 0;
@@ -481,19 +490,21 @@ char *url_nice(const char *url)
 
 	if (k == 0) {
 		free(rurl);
-		return result;
+		return URL_FUNC_OK;
 	}
 
 	/* reverse back */
 	for (i = 0, j = k - 1; i != k; i++, j--)
-		result[i] = buf[j];
-	result[k] = 0;
+		(*result)[i] = buf[j];
+	(*result)[k] = 0;
 
 	for (i = 0; i != k; i++)
-		if (result[i] != (char) 0xa0 && !isalnum(result[i]))
-			result[i] = '_';
+		if ((*result)[i] != (char) 0xa0 && !isalnum((*result)[i]))
+			(*result)[i] = '_';
+
+	free(rurl);
 
-	return result;
+	return URL_FUNC_OK;
 }
 
 
@@ -503,26 +514,35 @@ char *url_nice(const char *url)
 int main(int argc, char *argv[])
 {
 	int i;
+	url_func_result res;
 	char *s;
 	url_init();
-	for (i = 1; i != argc; i++) {
-/*		printf("==> '%s'\n", argv[i]);
-		s = url_normalize(argv[i]);
-		if (s)
-			printf("<== '%s'\n", s);*/
+/*	for (i = 1; i != argc; i++) {
+		printf("==> '%s'\n", argv[i]);
+		res = url_normalize(argv[i], &s);
+		if (res == URL_FUNC_OK) {
+			printf("<== '%s'\n", s);
+			free(s);
+		}*/
 /*		printf("==> '%s'\n", argv[i]);
-		s = url_host(argv[i]);
-		if (s)
-			printf("<== '%s'\n", s);*/
+		res = url_host(argv[i], &s);
+		if (res == URL_FUNC_OK) {
+			printf("<== '%s'\n", s);
+			free(s);
+		}*/
 /*		if (1 != i) {
-			s = url_join(argv[i], argv[1]);
-			if (s)
+			res = url_join(argv[i], argv[1], &s);
+			if (res == URL_FUNC_OK) {
 				printf("'%s' + '%s' \t= '%s'\n", argv[1],
 						argv[i], s);
+				free(s);
+			}
 		}*/
-		s = url_nice(argv[i]);
-		if (s)
+		res = url_nice(argv[i], &s);
+		if (res == URL_FUNC_OK) {
 			printf("'%s'\n", s);
+			free(s);
+		}
 	}
 	return 0;
 }
diff --git a/utils/url.h b/utils/url.h
index 96aa947f5..cc373b257 100644
--- a/utils/url.h
+++ b/utils/url.h
@@ -12,10 +12,16 @@
 #ifndef _NETSURF_UTILS_URL_H_
 #define _NETSURF_UTILS_URL_H_
 
+typedef enum {
+	URL_FUNC_OK,     /**< No error */
+	URL_FUNC_NOMEM,  /**< Insufficient memory */
+	URL_FUNC_FAILED  /**< Non fatal error (eg failed to match regex) */
+} url_func_result;
+
 void url_init(void);
-char *url_normalize(const char *url);
-char *url_join(const char *rel, const char *base);
-char *url_host(const char *url);
-char *url_nice(const char *url);
+url_func_result url_normalize(const char *url, char **result);
+url_func_result url_join(const char *rel, const char *base, char **result);
+url_func_result url_host(const char *url, char **result);
+url_func_result url_nice(const char *url, char **result);
 
 #endif