/* 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 "config.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 bool
bz2_open_stream(struct archive_file *file, struct input_stream *is,
G_GNUC_UNUSED const char *path)
{
bz2_context *context = (bz2_context *) file;
//setup file ops
is->plugin = &bz2_inputplugin;
//insert back reference
is->data = context;
is->seekable = false;
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->data;
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->data;
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->data;
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 = {
.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,
.open_stream = bz2_open_stream,
.close = bz2_close,
.suffixes = bz2_extensions
};
