low level source data cache backing store interface.

content/Makefile

@@ -1,6 +1,6 @@
 # Content sources
 
 S_CONTENT := content.c content_factory.c dirlist.c fetch.c hlcache.c	\
-	llcache.c mimesniff.c urldb.c
+	llcache.c mimesniff.c urldb.c no_backing_store.c
 
-S_CONTENT := $(addprefix content/,$(S_CONTENT))
+S_CONTENT := $(addprefix content/,$(S_CONTENT))

content/backing_store.h

@@ -0,0 +1,100 @@
+/*
+ * Copyright 2014 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * 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
+ * Low-level source data cache backing store interface
+ */
+
+#ifndef NETSURF_CONTENT_LLCACHE_PRIVATE_H_
+#define NETSURF_CONTENT_LLCACHE_PRIVATE_H_
+
+#include "content/llcache.h"
+
+/** storage control flags */
+enum backing_store_flags {
+	BACKING_STORE_NONE = 0, /**< no special processing */
+	BACKING_STORE_META = 1, /**< data is metadata */
+	BACKING_STORE_MMAP = 2, /**< when data is retrived this indicates the
+				 * returned buffer may be memory mapped,
+				 * flag must be cleared if the storage is
+				 * allocated and is not memory mapped.
+				 */
+};
+
+/** low level cache backing store operation table
+ *
+ * The low level cache (source objects) has the capability to make
+ * objects and their metadata (headers etc) persistant by writing to a
+ * backing store using these operations.
+ */
+struct gui_llcache_table {
+	/**
+	 * Initialise the backing store.
+	 *
+	 * @param parameters to configure backing store.
+	 * @return NSERROR_OK on success or error code on faliure.
+	 */
+	nserror (*initialise)(const struct llcache_store_parameters *parameters);
+
+	/**
+	 * Finalise the backing store.
+	 *
+	 * @return NSERROR_OK on success or error code on faliure.
+	 */
+	nserror (*finalise)(void);
+
+	/**
+	 * Place an object in the backing store.
+	 *
+	 * @param url The url is used as the unique primary key for the data.
+	 * @param flags The flags to control how the obejct is stored.
+	 * @param data The objects data.
+	 * @param datalen The length of the \a data.
+	 * @return NSERROR_OK on success or error code on faliure.
+	 */
+	nserror (*store)(struct nsurl *url, enum backing_store_flags flags,
+			 const uint8_t *data, const size_t datalen);
+
+	/**
+	 * Retrive an object from the backing store.
+	 *
+	 * @param url The url is used as the unique primary key for the data.
+	 * @param flags The flags to control how the object is retrived.
+	 * @param data The objects data.
+	 * @param datalen The length of the \a data retrieved.
+	 * @return NSERROR_OK on success or error code on faliure.
+	 */
+	nserror (*fetch)(struct nsurl *url, enum backing_store_flags *flags,
+			 uint8_t **data, size_t *datalen);
+
+	/**
+	 * Invalidate a source object from the backing store.
+	 *
+	 * The entry (if present in the backing store) must no longer
+	 * be returned as a result to the fetch or meta operations.
+	 *
+	 * @param url The url is used as the unique primary key to invalidate.
+	 * @return NSERROR_OK on success or error code on faliure.
+	 */
+	nserror (*invalidate)(struct nsurl *url);
+};
+
+extern struct gui_llcache_table* null_llcache_table;
+extern struct gui_llcache_table* filesystem_llcache_table;
+
+#endif

content/no_backing_store.c

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2014 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * 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
+ * Low-level resource cache null persistant storage implementation.
+ */
+
+#include "utils/nsurl.h"
+
+#include "content/backing_store.h"
+
+
+/* default to disabled backing store */
+static nserror initialise(const struct llcache_store_parameters *parameters)
+{
+	return NSERROR_OK;
+}
+
+static nserror finalise(void)
+{
+	return NSERROR_OK;
+}
+
+static nserror store(nsurl *url,
+		     enum backing_store_flags flags,
+		     const uint8_t *data,
+		     const size_t datalen)
+{
+	return NSERROR_SAVE_FAILED;
+}
+
+static nserror fetch(nsurl *url,
+		     enum backing_store_flags *flags,
+		     uint8_t **data_out,
+		     size_t *datalen_out)
+{
+	return NSERROR_NOT_FOUND;
+}
+
+static nserror invalidate(nsurl *url)
+{
+	return NSERROR_NOT_FOUND;
+}
+
+static struct gui_llcache_table llcache_table = {
+	.initialise = initialise,
+	.finalise = finalise,
+	.store = store,
+	.fetch = fetch,
+	.invalidate = invalidate,
+};
+
+struct gui_llcache_table *null_llcache_table = &llcache_table;

desktop/gui.h

@@ -69,6 +69,7 @@ struct hlcache_handle;
 struct download_context;
 struct nsurl;
 struct gui_file_table;
+struct gui_llcache_table;
 
 typedef struct nsnsclipboard_styles {
 	size_t start;			/**< Start of run */
@@ -520,7 +521,6 @@ struct gui_browser_table {
 
 };
 
-
 /**
  * NetSurf operation function table
  *
@@ -572,6 +572,15 @@ struct netsurf_table {
 	 * Provides routines for the interactive text search on a page.
 	 */
 	struct gui_search_table *search;
+
+	/**
+	 * Low level cache table.
+	 *
+	 * Used by the low level cache to push objects to persistant
+	 * storage. The table is optional and may be NULL which
+	 * uses the default implementation.
+	 */
+	struct gui_llcache_table *llcache;
 };
 
 

desktop/gui_factory.c

@@ -17,6 +17,8 @@
  */
 
 #include "content/hlcache.h"
+#include "content/backing_store.h"
+
 #include "desktop/download.h"
 #include "desktop/gui_factory.h"
 #include "utils/file.h"
@@ -25,7 +27,6 @@
 struct netsurf_table *guit = NULL;
 
 
-
 static void gui_default_window_set_title(struct gui_window *g, const char *title)
 {
 }
@@ -400,6 +401,34 @@ static nserror verify_search_register(struct gui_search_table *gst)
 	return NSERROR_OK;
 }
 
+/** verify low level cache persistant backing store table is valid */
+static nserror verify_llcache_register(struct gui_llcache_table *glt)
+{
+	/* check table is present */
+	if (glt == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+
+	/* mandantory operations */
+	if (glt->store == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+	if (glt->fetch == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+	if (glt->invalidate == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+	if (glt->initialise == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+	if (glt->finalise == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+
+	return NSERROR_OK;
+}
+
 static nsurl *gui_default_get_resource_url(const char *path)
 {
 	return NULL;
@@ -622,6 +651,16 @@ nserror gui_factory_register(struct netsurf_table *gt)
 		return err;
 	}
 
+	/* llcache table */
+	if (gt->llcache == NULL) {
+		/* set default backing store table */
+		gt->llcache = null_llcache_table;
+	}
+	err = verify_llcache_register(gt->llcache);
+	if (err != NSERROR_OK) {
+		return err;
+	}
+
 	guit = gt;
 
 	return NSERROR_OK;