archiveapi: archive plugin for BZ2 files

1 files changed, 303 insertions, 0 deletions

diff --git a/src/archive/bz2_plugin.c b/src/archive/bz2_plugin.c
new file mode 100644
index 00000000..00c59c69
--- /dev/null
+++ b/src/archive/bz2_plugin.c
@@ -0,0 +1,303 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2008 Viliam Mateicka <viliam.mateicka@gmail.com>
+ * This project's homepage is: 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/**
+  * single bz2 archive handling (requires libbz2)
+  */
+
+#include "archive_api.h"
+#include "input_stream.h"
+#include "utils.h"
+
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include <glib.h>
+#include <bzlib.h>
+
+#ifdef HAVE_OLDER_BZIP2
+#define BZ2_bzDecompressInit  bzDecompressInit
+#define BZ2_bzDecompress      bzDecompress
+#endif
+
+#define BZ_BUFSIZE   5000
+
+typedef struct {
+	char		*name;
+	bool		reset;
+	struct input_stream istream;
+	int		last_bz_result;
+	int		last_parent_result;
+	bz_stream	bzstream;
+	char		*buffer;
+} bz2_context;
+
+
+static const struct input_plugin bz2_inputplugin;
+
+/* single archive handling allocation helpers */
+
+static bool
+bz2_alloc(bz2_context *data)
+{
+	data->bzstream.bzalloc = NULL;
+	data->bzstream.bzfree  = NULL;
+	data->bzstream.opaque  = NULL;
+
+	data->buffer = g_malloc(BZ_BUFSIZE);
+	data->bzstream.next_in = (void *) data->buffer;
+	data->bzstream.avail_in = 0;
+
+	if (BZ2_bzDecompressInit(&data->bzstream, 0, 0) != BZ_OK) {
+		g_free(data->buffer);
+		g_free(data);
+		return false;
+	}
+
+	data->last_bz_result = BZ_OK;
+	data->last_parent_result = 0;
+	return true;
+}
+
+static void
+bz2_destroy(bz2_context *data)
+{
+	BZ2_bzDecompressEnd(&data->bzstream);
+	g_free(data->buffer);
+}
+
+/* archive open && listing routine */
+
+static struct archive_file *
+bz2_open(char * pathname)
+{
+	bz2_context *context;
+	char *name;
+	int len;
+
+	context = g_malloc(sizeof(bz2_context));
+	if (!context) {
+		return NULL;
+	}
+	//open archive
+	if (!input_stream_open(&context->istream, pathname)) {
+		g_warning("failed to open an bzip2 archive %s\n",pathname);
+		g_free(context);
+		return NULL;
+	}
+	//capture filename
+	name = strrchr(pathname, '/');
+	if (name == NULL) {
+		g_warning("failed to get bzip2 name from %s\n",pathname);
+		g_free(context);
+		return NULL;
+	}
+	context->name = g_strdup(name+1);
+	//remove suffix
+	len = strlen(context->name);
+	if (len > 4) {
+		context->name[len-4] = 0; //remove .bz2 suffix
+	}
+	return (struct archive_file *) context;
+}
+
+static void
+bz2_scan_reset(struct archive_file *file)
+{
+	bz2_context *context = (bz2_context *) file;
+	context->reset = true;
+}
+
+static char *
+bz2_scan_next(struct archive_file *file)
+{
+	bz2_context *context = (bz2_context *) file;
+	char *name = NULL;
+	if (context->reset) {
+		name = context->name;
+		context->reset = false;
+	}
+	return name;
+}
+
+static void
+bz2_close(struct archive_file *file)
+{
+	bz2_context *context = (bz2_context *) file;
+	if (context->name)
+		g_free(context->name);
+
+	input_stream_close(&context->istream);
+	g_free(context);
+}
+
+/* single archive handling */
+
+static void
+bz2_setup_stream(struct archive_file *file, struct input_stream *is)
+{
+	bz2_context *context = (bz2_context *) file;
+	//setup file ops
+	is->plugin = &bz2_inputplugin;
+	//insert back reference
+	is->archive = context;
+	is->seekable = false;
+}
+
+
+static bool
+bz2_is_open(struct input_stream *is, G_GNUC_UNUSED const char *url)
+{
+	bz2_context *context = (bz2_context *) is->archive;
+
+	if (!bz2_alloc(context)) {
+		g_warning("alloc bz2 failed\n");
+		return false;
+	}
+	return true;
+}
+
+static void
+bz2_is_close(struct input_stream *is)
+{
+	bz2_context *context = (bz2_context *) is->archive;
+	bz2_destroy(context);
+	is->data = NULL;
+}
+
+static int
+bz2_fillbuffer(bz2_context *context,
+	size_t numBytes)
+{
+	size_t count;
+	bz_stream *bzstream;
+
+	bzstream = &context->bzstream;
+
+	if (bzstream->avail_in > 0)
+		return 0;
+
+	count = input_stream_read(&context->istream,
+			context->buffer, BZ_BUFSIZE);
+
+	if (count == 0) {
+		if (bzstream->avail_out == numBytes)
+			return -1;
+		if (!input_stream_eof(&context->istream))
+			context->last_parent_result = 1;
+	} else {
+		bzstream->next_in = context->buffer;
+		bzstream->avail_in = count;
+	}
+
+	return 0;
+}
+
+static size_t
+bz2_is_read(struct input_stream *is, void *ptr, size_t size)
+{
+	bz2_context *context = (bz2_context *) is->archive;
+	bz_stream *bzstream;
+	int bz_result;
+	size_t numBytes = size;
+	size_t bytesRead = 0;
+
+	if (context->last_bz_result != BZ_OK)
+		return 0;
+	if (context->last_parent_result != 0)
+		return 0;
+
+	bzstream = &context->bzstream;
+	bzstream->next_out = ptr;
+	bzstream->avail_out = numBytes;
+
+	while (bzstream->avail_out != 0) {
+		if (bz2_fillbuffer(context, numBytes) != 0)
+			break;
+
+		bz_result = BZ2_bzDecompress(bzstream);
+
+		if (context->last_bz_result != BZ_OK
+		    && bzstream->avail_out == numBytes) {
+			context->last_bz_result = bz_result;
+			break;
+		}
+
+		if (bz_result == BZ_STREAM_END) {
+			context->last_bz_result = bz_result;
+			break;
+		}
+	}
+
+	bytesRead = numBytes - bzstream->avail_out;
+	is->offset += bytesRead;
+
+	return bytesRead;
+}
+
+static bool
+bz2_is_eof(struct input_stream *is)
+{
+	bz2_context *context = (bz2_context *) is->archive;
+
+	if (context->last_bz_result == BZ_STREAM_END) {
+		return true;
+	}
+
+	return false;
+}
+
+static bool
+bz2_is_seek(G_GNUC_UNUSED struct input_stream *is,
+	G_GNUC_UNUSED off_t offset, G_GNUC_UNUSED int whence)
+{
+	return false;
+}
+
+static int
+bz2_is_buffer(G_GNUC_UNUSED struct input_stream *is)
+{
+	return 0;
+}
+
+/* exported structures */
+
+static const char *const bz2_extensions[] = {
+	"bz2",
+	NULL
+};
+
+static const struct input_plugin bz2_inputplugin = {
+	.open = bz2_is_open,
+	.close = bz2_is_close,
+	.read = bz2_is_read,
+	.eof = bz2_is_eof,
+	.seek = bz2_is_seek,
+	.buffer = bz2_is_buffer
+};
+
+const struct archive_plugin bz2_plugin = {
+	.name = "bz2",
+	.open = bz2_open,
+	.scan_reset = bz2_scan_reset,
+	.scan_next = bz2_scan_next,
+	.setup_stream = bz2_setup_stream,
+	.close = bz2_close,
+	.suffixes = bz2_extensions
+};
+