268 lines
6.3 KiB
C
268 lines
6.3 KiB
C
/*
|
|
* Copyright (C) 2003-2011 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.
|
|
*/
|
|
|
|
#ifndef MPD_INPUT_STREAM_H
|
|
#define MPD_INPUT_STREAM_H
|
|
|
|
#include "check.h"
|
|
#include "gcc.h"
|
|
|
|
#include <glib.h>
|
|
|
|
#include <stddef.h>
|
|
#include <stdbool.h>
|
|
#include <sys/types.h>
|
|
|
|
struct input_stream {
|
|
/**
|
|
* the plugin which implements this input stream
|
|
*/
|
|
const struct input_plugin *plugin;
|
|
|
|
/**
|
|
* The absolute URI which was used to open this stream. May
|
|
* be NULL if this is unknown.
|
|
*/
|
|
char *uri;
|
|
|
|
/**
|
|
* A mutex that protects the mutable attributes of this object
|
|
* and its implementation. It must be locked before calling
|
|
* any of the public methods.
|
|
*
|
|
* This object is allocated by the client, and the client is
|
|
* responsible for freeing it.
|
|
*/
|
|
GMutex *mutex;
|
|
|
|
/**
|
|
* A cond that gets signalled when the state of this object
|
|
* changes from the I/O thread. The client of this object may
|
|
* wait on it. Optional, may be NULL.
|
|
*
|
|
* This object is allocated by the client, and the client is
|
|
* responsible for freeing it.
|
|
*/
|
|
GCond *cond;
|
|
|
|
/**
|
|
* indicates whether the stream is ready for reading and
|
|
* whether the other attributes in this struct are valid
|
|
*/
|
|
bool ready;
|
|
|
|
/**
|
|
* if true, then the stream is fully seekable
|
|
*/
|
|
bool seekable;
|
|
|
|
/**
|
|
* the size of the resource, or -1 if unknown
|
|
*/
|
|
goffset size;
|
|
|
|
/**
|
|
* the current offset within the stream
|
|
*/
|
|
goffset offset;
|
|
|
|
/**
|
|
* the MIME content type of the resource, or NULL if unknown
|
|
*/
|
|
char *mime;
|
|
};
|
|
|
|
/**
|
|
* Opens a new input stream. You may not access it until the "ready"
|
|
* flag is set.
|
|
*
|
|
* @param mutex a mutex that is used to protect this object; must be
|
|
* locked before calling any of the public methods
|
|
* @param cond a cond that gets signalled when the state of
|
|
* this object changes; may be NULL if the caller doesn't want to get
|
|
* notifications
|
|
* @return an #input_stream object on success, NULL on error
|
|
*/
|
|
gcc_nonnull(1, 2)
|
|
G_GNUC_MALLOC
|
|
struct input_stream *
|
|
input_stream_open(const char *uri,
|
|
GMutex *mutex, GCond *cond,
|
|
GError **error_r);
|
|
|
|
/**
|
|
* Close the input stream and free resources.
|
|
*
|
|
* The caller must not lock the mutex.
|
|
*/
|
|
gcc_nonnull(1)
|
|
void
|
|
input_stream_close(struct input_stream *is);
|
|
|
|
gcc_nonnull(1)
|
|
static inline void
|
|
input_stream_lock(struct input_stream *is)
|
|
{
|
|
g_mutex_lock(is->mutex);
|
|
}
|
|
|
|
gcc_nonnull(1)
|
|
static inline void
|
|
input_stream_unlock(struct input_stream *is)
|
|
{
|
|
g_mutex_unlock(is->mutex);
|
|
}
|
|
|
|
/**
|
|
* Check for errors that may have occurred in the I/O thread.
|
|
*
|
|
* @return false on error
|
|
*/
|
|
gcc_nonnull(1)
|
|
bool
|
|
input_stream_check(struct input_stream *is, GError **error_r);
|
|
|
|
/**
|
|
* Update the public attributes. Call before accessing attributes
|
|
* such as "ready" or "offset".
|
|
*/
|
|
gcc_nonnull(1)
|
|
void
|
|
input_stream_update(struct input_stream *is);
|
|
|
|
/**
|
|
* Wait until the stream becomes ready.
|
|
*
|
|
* The caller must lock the mutex.
|
|
*/
|
|
gcc_nonnull(1)
|
|
void
|
|
input_stream_wait_ready(struct input_stream *is);
|
|
|
|
/**
|
|
* Wrapper for input_stream_wait_locked() which locks and unlocks the
|
|
* mutex; the caller must not be holding it already.
|
|
*/
|
|
gcc_nonnull(1)
|
|
void
|
|
input_stream_lock_wait_ready(struct input_stream *is);
|
|
|
|
/**
|
|
* Seeks to the specified position in the stream. This will most
|
|
* likely fail if the "seekable" flag is false.
|
|
*
|
|
* The caller must lock the mutex.
|
|
*
|
|
* @param is the input_stream object
|
|
* @param offset the relative offset
|
|
* @param whence the base of the seek, one of SEEK_SET, SEEK_CUR, SEEK_END
|
|
*/
|
|
gcc_nonnull(1)
|
|
bool
|
|
input_stream_seek(struct input_stream *is, goffset offset, int whence,
|
|
GError **error_r);
|
|
|
|
/**
|
|
* Wrapper for input_stream_seek() which locks and unlocks the
|
|
* mutex; the caller must not be holding it already.
|
|
*/
|
|
gcc_nonnull(1)
|
|
bool
|
|
input_stream_lock_seek(struct input_stream *is, goffset offset, int whence,
|
|
GError **error_r);
|
|
|
|
/**
|
|
* Returns true if the stream has reached end-of-file.
|
|
*
|
|
* The caller must lock the mutex.
|
|
*/
|
|
gcc_nonnull(1)
|
|
G_GNUC_PURE
|
|
bool input_stream_eof(struct input_stream *is);
|
|
|
|
/**
|
|
* Wrapper for input_stream_eof() which locks and unlocks the mutex;
|
|
* the caller must not be holding it already.
|
|
*/
|
|
gcc_nonnull(1)
|
|
G_GNUC_PURE
|
|
bool
|
|
input_stream_lock_eof(struct input_stream *is);
|
|
|
|
/**
|
|
* Reads the tag from the stream.
|
|
*
|
|
* The caller must lock the mutex.
|
|
*
|
|
* @return a tag object which must be freed with tag_free(), or NULL
|
|
* if the tag has not changed since the last call
|
|
*/
|
|
gcc_nonnull(1)
|
|
G_GNUC_MALLOC
|
|
struct tag *
|
|
input_stream_tag(struct input_stream *is);
|
|
|
|
/**
|
|
* Wrapper for input_stream_tag() which locks and unlocks the
|
|
* mutex; the caller must not be holding it already.
|
|
*/
|
|
gcc_nonnull(1)
|
|
G_GNUC_MALLOC
|
|
struct tag *
|
|
input_stream_lock_tag(struct input_stream *is);
|
|
|
|
/**
|
|
* Returns true if the next read operation will not block: either data
|
|
* is available, or end-of-stream has been reached, or an error has
|
|
* occurred.
|
|
*
|
|
* The caller must lock the mutex.
|
|
*/
|
|
gcc_nonnull(1)
|
|
G_GNUC_PURE
|
|
bool
|
|
input_stream_available(struct input_stream *is);
|
|
|
|
/**
|
|
* Reads data from the stream into the caller-supplied buffer.
|
|
* Returns 0 on error or eof (check with input_stream_eof()).
|
|
*
|
|
* The caller must lock the mutex.
|
|
*
|
|
* @param is the input_stream object
|
|
* @param ptr the buffer to read into
|
|
* @param size the maximum number of bytes to read
|
|
* @return the number of bytes read
|
|
*/
|
|
gcc_nonnull(1, 2)
|
|
size_t
|
|
input_stream_read(struct input_stream *is, void *ptr, size_t size,
|
|
GError **error_r);
|
|
|
|
/**
|
|
* Wrapper for input_stream_tag() which locks and unlocks the
|
|
* mutex; the caller must not be holding it already.
|
|
*/
|
|
gcc_nonnull(1, 2)
|
|
size_t
|
|
input_stream_lock_read(struct input_stream *is, void *ptr, size_t size,
|
|
GError **error_r);
|
|
|
|
#endif
|