1 files changed, 325 insertions, 0 deletions
diff --git a/content/handlers/html/html_css_fetcher.c b/content/handlers/html/html_css_fetcher.c
new file mode 100644
index 000000000..7987ea094
--- /dev/null
+++ b/content/handlers/html/html_css_fetcher.c
@@ -0,0 +1,325 @@
+/*
+ * Copyright 2008 Rob Kendrick <rjek@netsurf-browser.org>
+ * Copyright 2013 John-Mark Bell <jmb@netsurf-browser.org>
+ *
+ * This file is part of NetSurf.
+ *
+ * NetSurf 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; version 2 of the License.
+ *
+ * NetSurf 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, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * \file
+ * HTML fetcher for CSS objects
+ */
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dom/dom.h>
+#include <libwapcaplet/libwapcaplet.h>
+
+#include "netsurf/inttypes.h"
+#include "utils/config.h"
+#include "utils/log.h"
+#include "utils/ring.h"
+#include "utils/nsurl.h"
+#include "utils/utils.h"
+#include "content/fetch.h"
+#include "content/fetchers.h"
+
+#include "html/html_internal.h"
+
+typedef struct html_css_fetcher_item {
+	uint32_t key;
+	dom_string *data;
+	nsurl *base_url;
+
+	struct html_css_fetcher_item *r_next, *r_prev;
+} html_css_fetcher_item;
+
+typedef struct html_css_fetcher_context {
+	struct fetch *parent_fetch;
+
+	nsurl *url;
+	html_css_fetcher_item *item;
+
+	bool aborted;
+	bool locked;
+
+	struct html_css_fetcher_context *r_next, *r_prev;
+} html_css_fetcher_context;
+
+static uint32_t current_key = 0;
+static html_css_fetcher_item *items = NULL;
+static html_css_fetcher_context *ring = NULL;
+
+static bool html_css_fetcher_initialise(lwc_string *scheme)
+{
+	NSLOG(netsurf, INFO, "html_css_fetcher_initialise called for %s",
+	      lwc_string_data(scheme));
+	return true;
+}
+
+static void html_css_fetcher_finalise(lwc_string *scheme)
+{
+	NSLOG(netsurf, INFO, "html_css_fetcher_finalise called for %s",
+	      lwc_string_data(scheme));
+}
+
+static bool html_css_fetcher_can_fetch(const nsurl *url)
+{
+	return true;
+}
+
+static void *html_css_fetcher_setup(struct fetch *parent_fetch, nsurl *url,
+		 bool only_2xx, bool downgrade_tls, const char *post_urlenc,
+		 const struct fetch_multipart_data *post_multipart,
+		 const char **headers)
+{
+	html_css_fetcher_context *ctx;
+	lwc_string *path;
+	uint32_t key;
+	html_css_fetcher_item *item, *found = NULL;
+
+	/* format of a x-ns-css URL is:
+	 *   x-ns-url:<key>
+	 * Where key is an unsigned 32bit integer
+	 */
+
+	path = nsurl_get_component(url, NSURL_PATH);
+	/* The path must exist */
+	if (path == NULL) {
+		return NULL;
+	}
+
+	key = strtoul(lwc_string_data(path), NULL, 10);
+
+	lwc_string_unref(path);
+
+	/* There must be at least one item */
+	if (items == NULL) {
+		return NULL;
+	}
+
+	item = items;
+	do {
+		if (item->key == key) {
+			found = item;
+			break;
+		}
+
+		item = item->r_next;
+	} while (item != items);
+
+	/* We must have found the item */
+	if (found == NULL) {
+		return NULL;
+	}
+
+	ctx = calloc(1, sizeof(*ctx));
+	if (ctx == NULL)
+		return NULL;
+
+	ctx->parent_fetch = parent_fetch;
+	ctx->url = nsurl_ref(url);
+	ctx->item = found;
+
+	RING_INSERT(ring, ctx);
+
+	return ctx;
+}
+
+static bool html_css_fetcher_start(void *ctx)
+{
+	return true;
+}
+
+static void html_css_fetcher_free(void *ctx)
+{
+	html_css_fetcher_context *c = ctx;
+
+	nsurl_unref(c->url);
+	if (c->item != NULL) {
+		nsurl_unref(c->item->base_url);
+		dom_string_unref(c->item->data);
+		RING_REMOVE(items, c->item);
+		free(c->item);
+	}
+	RING_REMOVE(ring, c);
+	free(ctx);
+}
+
+static void html_css_fetcher_abort(void *ctx)
+{
+	html_css_fetcher_context *c = ctx;
+
+	/* To avoid the poll loop having to deal with the fetch context
+	 * disappearing from under it, we simply flag the abort here.
+	 * The poll loop itself will perform the appropriate cleanup.
+	 */
+	c->aborted = true;
+}
+
+static void html_css_fetcher_send_callback(const fetch_msg *msg,
+		html_css_fetcher_context *c)
+{
+	c->locked = true;
+	fetch_send_callback(msg, c->parent_fetch);
+	c->locked = false;
+}
+
+static void html_css_fetcher_poll(lwc_string *scheme)
+{
+	fetch_msg msg;
+	html_css_fetcher_context *c, *next;
+
+	if (ring == NULL) return;
+
+	/* Iterate over ring, processing each pending fetch */
+	c = ring;
+	do {
+		/* Ignore fetches that have been flagged as locked.
+		 * This allows safe re-entrant calls to this function.
+		 * Re-entrancy can occur if, as a result of a callback,
+		 * the interested party causes fetch_poll() to be called
+		 * again.
+		 */
+		if (c->locked == true) {
+			next = c->r_next;
+			continue;
+		}
+
+		/* Only process non-aborted fetches */
+		if (c->aborted) {
+			/* Nothing to do */
+			assert(c->locked == false);
+		} else if (c->item != NULL) {
+			char header[4096];
+
+			fetch_set_http_code(c->parent_fetch, 200);
+
+			/* Any callback can result in the fetch being aborted.
+			 * Therefore, we _must_ check for this after _every_
+			 * call to html_css_fetcher_send_callback().
+			 */
+			snprintf(header, sizeof header,
+				"Content-Type: text/css; charset=utf-8");
+			msg.type = FETCH_HEADER;
+			msg.data.header_or_data.buf = (const uint8_t *) header;
+			msg.data.header_or_data.len = strlen(header);
+			html_css_fetcher_send_callback(&msg, c);
+
+			if (c->aborted == false) {
+				snprintf(header, sizeof header,
+					"Content-Length: %"PRIsizet,
+					dom_string_byte_length(c->item->data));
+				msg.type = FETCH_HEADER;
+				msg.data.header_or_data.buf =
+						(const uint8_t *) header;
+				msg.data.header_or_data.len = strlen(header);
+				html_css_fetcher_send_callback(&msg, c);
+			}
+
+			if (c->aborted == false) {
+				snprintf(header, sizeof header,
+					"X-NS-Base: %.*s",
+					(int) nsurl_length(c->item->base_url),
+					nsurl_access(c->item->base_url));
+				msg.type = FETCH_HEADER;
+				msg.data.header_or_data.buf =
+						(const uint8_t *) header;
+				msg.data.header_or_data.len = strlen(header);
+				html_css_fetcher_send_callback(&msg, c);
+			}
+
+			if (c->aborted == false) {
+				msg.type = FETCH_DATA;
+				msg.data.header_or_data.buf =
+						(const uint8_t *)
+						dom_string_data(c->item->data);
+				msg.data.header_or_data.len =
+					dom_string_byte_length(c->item->data);
+				html_css_fetcher_send_callback(&msg, c);
+			}
+
+			if (c->aborted == false) {
+				msg.type = FETCH_FINISHED;
+				html_css_fetcher_send_callback(&msg, c);
+			}
+		} else {
+			NSLOG(netsurf, INFO, "Processing of %s failed!",
+			      nsurl_access(c->url));
+
+			/* Ensure that we're unlocked here. If we aren't,
+			 * then html_css_fetcher_process() is broken.
+			 */
+			assert(c->locked == false);
+		}
+
+		/* Compute next fetch item at the last possible moment as
+		 * processing this item may have added to the ring.
+		 */
+		next = c->r_next;
+
+		fetch_remove_from_queues(c->parent_fetch);
+		fetch_free(c->parent_fetch);
+
+		/* Advance to next ring entry, exiting if we've reached
+		 * the start of the ring or the ring has become empty
+		 */
+	} while ( (c = next) != ring && ring != NULL);
+}
+
+/* exported interface documented in html_internal.h */
+nserror html_css_fetcher_register(void)
+{
+	lwc_string *scheme;
+	const struct fetcher_operation_table html_css_fetcher_ops = {
+		.initialise = html_css_fetcher_initialise,
+		.acceptable = html_css_fetcher_can_fetch,
+		.setup = html_css_fetcher_setup,
+		.start = html_css_fetcher_start,
+		.abort = html_css_fetcher_abort,
+		.free = html_css_fetcher_free,
+		.poll = html_css_fetcher_poll,
+		.finalise = html_css_fetcher_finalise
+	};
+
+	if (lwc_intern_string("x-ns-css", SLEN("x-ns-css"),
+			      &scheme) != lwc_error_ok) {
+		NSLOG(netsurf, INFO, "could not intern \"x-ns-css\".");
+		return NSERROR_INIT_FAILED;
+	}
+
+	return fetcher_add(scheme, &html_css_fetcher_ops);
+}
+
+/* exported interface documented in html_internal.h */
+nserror
+html_css_fetcher_add_item(dom_string *data, nsurl *base_url, uint32_t *key)
+{
+	html_css_fetcher_item *item = malloc(sizeof(*item));
+
+	if (item == NULL) {
+		return NSERROR_NOMEM;
+	}
+
+	*key = item->key = current_key++;
+	item->data = dom_string_ref(data);
+	item->base_url = nsurl_ref(base_url);
+
+	RING_INSERT(items, item);
+
+	return NSERROR_OK;
+}