archive_plugin: wrap method calls

Make archive_file a "real" struct, extended by all plugins.  Add the
plugin pointer to it.  Wrap all method calls in functions.

Makefile.am

@@ -369,6 +369,7 @@ if ENABLE_ARCHIVE
 ARCHIVE_SRC += \
 	src/archive_api.c \
 	src/archive_list.c \
+	src/archive_plugin.c \
 	src/input/archive_input_plugin.c
 endif
 

src/archive/bz2_archive_plugin.c

@@ -40,6 +40,8 @@
 #define BZ_BUFSIZE   5000
 
 struct bz2_archive_file {
+	struct archive_file base;
+
 	char *name;
 	bool reset;
 	struct input_stream istream;
@@ -102,6 +104,7 @@ bz2_open(const char *pathname)
 	int len;
 
 	context = g_malloc(sizeof(*context));
+	archive_file_init(&context->base, &bz2_archive_plugin);
 
 	//open archive
 	if (!input_stream_open(&context->istream, pathname, NULL)) {
@@ -118,7 +121,7 @@ bz2_open(const char *pathname)
 		context->name[len - 4] = 0; //remove .bz2 suffix
 	}
 
-	return (struct archive_file *) context;
+	return &context->base;
 }
 
 static void

src/archive/iso9660_archive_plugin.c

@@ -35,6 +35,8 @@
 #define CEILING(x, y) ((x+(y-1))/y)
 
 struct iso9660_archive_file {
+	struct archive_file base;
+
 	iso9660_t *iso;
 	iso9660_stat_t *statbuf;
 	size_t cur_ofs;
@@ -93,6 +95,8 @@ iso9660_archive_open(const char *pathname)
 	struct iso9660_archive_file *context =
 		g_new(struct iso9660_archive_file, 1);
 
+	archive_file_init(&context->base, &iso9660_archive_plugin);
+
 	context->list = NULL;
 
 	/* open archive */
@@ -104,7 +108,7 @@ iso9660_archive_open(const char *pathname)
 
 	listdir_recur("/", context);
 
-        return (struct archive_file *)context;
+	return &context->base;
 }
 
 static void

src/archive/zzip_archive_plugin.c

@@ -32,6 +32,8 @@
 #include <string.h>
 
 struct zzip_archive {
+	struct archive_file base;
+
 	ZZIP_DIR *dir;
 	ZZIP_FILE *file;
 	size_t	length;
@@ -55,6 +57,8 @@ zzip_archive_open(const char *pathname)
 	struct zzip_archive *context = g_malloc(sizeof(*context));
 	ZZIP_DIRENT dirent;
 
+	archive_file_init(&context->base, &zzip_archive_plugin);
+
 	// open archive
 	context->list = NULL;
 	context->dir = zzip_dir_open(pathname, NULL);
@@ -71,7 +75,7 @@ zzip_archive_open(const char *pathname)
 		}
 	}
 
-	return (struct archive_file *)context;
+	return &context->base;
 }
 
 static void

src/archive_internal.h

@@ -21,7 +21,14 @@
 #define MPD_ARCHIVE_INTERNAL_H
 
 struct archive_file {
-	int placeholder;
+	const struct archive_plugin *plugin;
 };
 
+static inline void
+archive_file_init(struct archive_file *archive_file,
+		  const struct archive_plugin *plugin)
+{
+	archive_file->plugin = plugin;
+}
+
 #endif

src/archive_plugin.c

@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2003-2009 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "archive_plugin.h"
+#include "archive_internal.h"
+
+#include <assert.h>
+
+struct archive_file *
+archive_file_open(const struct archive_plugin *plugin, const char *path)
+{
+	struct archive_file *file;
+
+	assert(plugin != NULL);
+	assert(plugin->open != NULL);
+	assert(path != NULL);
+
+	file = plugin->open(path);
+
+	if (file != NULL) {
+		assert(file->plugin != NULL);
+		assert(file->plugin->close != NULL);
+		assert(file->plugin->scan_reset != NULL);
+		assert(file->plugin->scan_next != NULL);
+		assert(file->plugin->open_stream != NULL);
+	}
+
+	return file;
+}
+
+void
+archive_file_close(struct archive_file *file)
+{
+	assert(file != NULL);
+	assert(file->plugin != NULL);
+	assert(file->plugin->close != NULL);
+
+	file->plugin->close(file);
+}
+
+void
+archive_file_scan_reset(struct archive_file *file)
+{
+	assert(file != NULL);
+	assert(file->plugin != NULL);
+	assert(file->plugin->scan_reset != NULL);
+	assert(file->plugin->scan_next != NULL);
+
+	file->plugin->scan_reset(file);
+}
+
+char *
+archive_file_scan_next(struct archive_file *file)
+{
+	assert(file != NULL);
+	assert(file->plugin != NULL);
+	assert(file->plugin->scan_next != NULL);
+
+	return file->plugin->scan_next(file);
+}
+
+bool
+archive_file_open_stream(struct archive_file *file, struct input_stream *is,
+			 const char *path, GError **error_r)
+{
+	assert(file != NULL);
+	assert(file->plugin != NULL);
+	assert(file->plugin->open_stream != NULL);
+
+	return file->plugin->open_stream(file, is, path, error_r);
+}

src/archive_plugin.h

@@ -89,5 +89,20 @@ struct archive_plugin {
 	const char *const*suffixes;
 };
 
-#endif
+struct archive_file *
+archive_file_open(const struct archive_plugin *plugin, const char *path);
 
+void
+archive_file_close(struct archive_file *file);
+
+void
+archive_file_scan_reset(struct archive_file *file);
+
+char *
+archive_file_scan_next(struct archive_file *file);
+
+bool
+archive_file_open_stream(struct archive_file *file, struct input_stream *is,
+			 const char *path, GError **error_r);
+
+#endif

src/input/archive_input_plugin.c

@@ -61,14 +61,14 @@ input_archive_open(struct input_stream *is, const char *pathname,
 		return false;
 	}
 
-	file = arplug->open(archive);
+	file = archive_file_open(arplug, archive);
 
 	//setup fileops
-	opened = arplug->open_stream(file, is, filename, error_r);
+	opened = archive_file_open_stream(file, is, filename, error_r);
 	g_free(pname);
 
 	if (!opened) {
-		arplug->close(file);
+		archive_file_close(file);
 	} else {
 		is->ready = true;
 	}

src/update_walk.c

@@ -409,7 +409,7 @@ update_archive_file(struct directory *parent, const char *name,
 	path_fs = map_directory_child_fs(parent, name);
 
 	/* open archive */
-	file = plugin->open(path_fs);
+	file = archive_file_open(plugin, path_fs);
 	if (file == NULL) {
 		g_warning("unable to open archive %s", path_fs);
 		g_free(path_fs);
@@ -429,15 +429,15 @@ update_archive_file(struct directory *parent, const char *name,
 
 	directory->mtime = st->st_mtime;
 
-	plugin->scan_reset(file);
+	archive_file_scan_reset(file);
 
-	while ((filepath = plugin->scan_next(file)) != NULL) {
+	while ((filepath = archive_file_scan_next(file)) != NULL) {
 		/* split name into directory and file */
 		g_debug("adding archive file: %s", filepath);
 		update_archive_tree(directory, filepath);
 	}
 
-	plugin->close(file);
+	archive_file_close(file);
 }
 #endif