gstreamer/gst/gstmemory.h
2012-09-10 12:20:15 +02:00

325 lines
9.8 KiB
C

/* GStreamer
* Copyright (C) 2009 Wim Taymans <wim.taymans@gmail.be>
*
* gstmemory.h: Header for memory blocks
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_MEMORY_H__
#define __GST_MEMORY_H__
#include <gst/gstconfig.h>
#include <glib-object.h>
G_BEGIN_DECLS
#define GST_TYPE_MEMORY (gst_memory_get_type())
GType gst_memory_get_type(void);
typedef struct _GstMemory GstMemory;
typedef struct _GstAllocator GstAllocator;
#define GST_MEMORY_CAST(mem) ((GstMemory *)(mem))
/**
* GstMemoryFlags:
* @GST_MEMORY_FLAG_READONLY: memory is readonly. It is not allowed to map the
* memory with #GST_MAP_WRITE.
* @GST_MEMORY_FLAG_NO_SHARE: memory must not be shared. Copies will have to be
* made when this memory needs to be shared between buffers.
* @GST_MEMORY_FLAG_ZERO_PREFIXED: the memory prefix is filled with 0 bytes
* @GST_MEMORY_FLAG_ZERO_PADDED: the memory padding is filled with 0 bytes
* @GST_MEMORY_FLAG_LAST: first flag that can be used for custom purposes
*
* Flags for wrapped memory.
*/
typedef enum {
GST_MEMORY_FLAG_READONLY = GST_MINI_OBJECT_FLAG_LOCK_READONLY,
GST_MEMORY_FLAG_NO_SHARE = (GST_MINI_OBJECT_FLAG_LAST << 0),
GST_MEMORY_FLAG_ZERO_PREFIXED = (GST_MINI_OBJECT_FLAG_LAST << 1),
GST_MEMORY_FLAG_ZERO_PADDED = (GST_MINI_OBJECT_FLAG_LAST << 2),
GST_MEMORY_FLAG_LAST = (GST_MINI_OBJECT_FLAG_LAST << 16)
} GstMemoryFlags;
/**
* GST_MEMORY_FLAGS:
* @mem: a #GstMemory.
*
* A flags word containing #GstMemoryFlags flags set on @mem
*/
#define GST_MEMORY_FLAGS(mem) GST_MINI_OBJECT_FLAGS (mem)
/**
* GST_MEMORY_FLAG_IS_SET:
* @mem: a #GstMemory.
* @flag: the #GstMemoryFlags to check.
*
* Gives the status of a specific flag on a @mem.
*/
#define GST_MEMORY_FLAG_IS_SET(mem,flag) GST_MINI_OBJECT_FLAG_IS_SET (mem,flag)
/**
* GST_MEMORY_FLAG_UNSET:
* @mem: a #GstMemory.
* @flag: the #GstMemoryFlags to clear.
*
* Clear a specific flag on a @mem.
*/
#define GST_MEMORY_FLAG_UNSET(mem,flag) GST_MINI_OBJECT_FLAG_UNSET (mem, flag)
/**
* GST_MEMORY_IS_READONLY:
* @mem: a #GstMemory.
*
* Check if @mem is readonly.
*/
#define GST_MEMORY_IS_READONLY(mem) GST_MEMORY_FLAG_IS_SET(mem,GST_MEMORY_FLAG_READONLY)
/**
* GST_MEMORY_IS_NO_SHARE:
* @mem: a #GstMemory.
*
* Check if @mem cannot be shared between buffers
*/
#define GST_MEMORY_IS_NO_SHARE(mem) GST_MEMORY_FLAG_IS_SET(mem,GST_MEMORY_FLAG_NO_SHARE)
/**
* GST_MEMORY_IS_ZERO_PREFIXED:
* @mem: a #GstMemory.
*
* Check if the prefix in @mem is 0 filled.
*/
#define GST_MEMORY_IS_ZERO_PREFIXED(mem) GST_MEMORY_FLAG_IS_SET(mem,GST_MEMORY_FLAG_ZERO_PREFIXED)
/**
* GST_MEMORY_IS_ZERO_PADDED:
* @mem: a #GstMemory.
*
* Check if the padding in @mem is 0 filled.
*/
#define GST_MEMORY_IS_ZERO_PADDED(mem) GST_MEMORY_FLAG_IS_SET(mem,GST_MEMORY_FLAG_ZERO_PADDED)
/**
* GstMemory:
* @mini_object: parent structure
* @allocator: pointer to the #GstAllocator
* @parent: parent memory block
* @maxsize: the maximum size allocated
* @align: the alignment of the memory
* @offset: the offset where valid data starts
* @size: the size of valid data
*
* Base structure for memory implementations. Custom memory will put this structure
* as the first member of their structure.
*/
struct _GstMemory {
GstMiniObject mini_object;
GstAllocator *allocator;
GstMemory *parent;
gsize maxsize;
gsize align;
gsize offset;
gsize size;
};
/**
* GstMapFlags:
* @GST_MAP_READ: map for read access
* @GST_MAP_WRITE: map for write access
* @GST_MAP_FLAG_LAST: first flag that can be used for custom purposes
*
* Flags used when mapping memory
*/
typedef enum {
GST_MAP_READ = GST_LOCK_FLAG_READ,
GST_MAP_WRITE = GST_LOCK_FLAG_WRITE,
GST_MAP_FLAG_LAST = (1 << 16)
} GstMapFlags;
/**
* GST_MAP_READWRITE:
*
* GstMapFlags value alias for GST_MAP_READ | GST_MAP_WRITE
*/
#define GST_MAP_READWRITE (GST_MAP_READ | GST_MAP_WRITE)
/**
* GstMapInfo:
* @memory: a pointer to the mapped memory
* @flags: flags used when mapping the memory
* @data: (array length=size): a pointer to the mapped data
* @size: the valid size in @data
* @maxsize: the maximum bytes in @data
* @user_data: extra private user_data that the implementation of the memory
* can use to store extra info.
*
* A structure containing the result of a map operation such as
* gst_memory_map(). It contains the data and size.
*/
typedef struct {
GstMemory *memory;
GstMapFlags flags;
guint8 *data;
gsize size;
gsize maxsize;
/*< protected >*/
gpointer user_data[4];
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
} GstMapInfo;
/**
* GST_MAP_INFO_INIT:
*
* Initializer for #GstMapInfo
*/
#define GST_MAP_INFO_INIT { NULL, 0, NULL, 0, 0, }
/**
* GstMemoryMapFunction:
* @mem: a #GstMemory
* @maxsize: size to map
* @flags: access mode for the memory
*
* Get the memory of @mem that can be accessed according to the mode specified
* in @flags. The function should return a pointer that contains at least
* @maxsize bytes.
*
* Returns: a pointer to memory of which at least @maxsize bytes can be
* accessed according to the access pattern in @flags.
*/
typedef gpointer (*GstMemoryMapFunction) (GstMemory *mem, gsize maxsize, GstMapFlags flags);
/**
* GstMemoryUnmapFunction:
* @mem: a #GstMemory
*
* Return the pointer previously retrieved with gst_memory_map().
*
* Returns: %TRUE on success.
*/
typedef void (*GstMemoryUnmapFunction) (GstMemory *mem);
/**
* GstMemoryCopyFunction:
* @mem: a #GstMemory
* @offset: an offset
* @size: a size or -1
*
* Copy @size bytes from @mem starting at @offset and return them wrapped in a
* new GstMemory object.
* If @size is set to -1, all bytes starting at @offset are copied.
*
* Returns: a new #GstMemory object wrapping a copy of the requested region in
* @mem.
*/
typedef GstMemory * (*GstMemoryCopyFunction) (GstMemory *mem, gssize offset, gssize size);
/**
* GstMemoryShareFunction:
* @mem: a #GstMemory
* @offset: an offset
* @size: a size or -1
*
* Share @size bytes from @mem starting at @offset and return them wrapped in a
* new GstMemory object. If @size is set to -1, all bytes starting at @offset are
* shared. This function does not make a copy of the bytes in @mem.
*
* Returns: a new #GstMemory object sharing the requested region in @mem.
*/
typedef GstMemory * (*GstMemoryShareFunction) (GstMemory *mem, gssize offset, gssize size);
/**
* GstMemoryIsSpanFunction:
* @mem1: a #GstMemory
* @mem2: a #GstMemory
* @offset: a result offset
*
* Check if @mem1 and @mem2 occupy contiguous memory and return the offset of
* @mem1 in the parent buffer in @offset.
*
* Returns: %TRUE if @mem1 and @mem2 are in contiguous memory.
*/
typedef gboolean (*GstMemoryIsSpanFunction) (GstMemory *mem1, GstMemory *mem2, gsize *offset);
void gst_memory_init (GstMemory *mem, GstMemoryFlags flags,
GstAllocator *allocator, GstMemory *parent,
gsize maxsize, gsize align,
gsize offset, gsize size);
/* refcounting */
/**
* gst_memory_ref:
* @memory: The memory to refcount
*
* Increase the refcount of this memory.
*
* Returns: (transfer full): @memory (for convenience when doing assignments)
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC GstMemory * gst_memory_ref (GstMemory * memory);
#endif
static inline GstMemory *
gst_memory_ref (GstMemory * memory)
{
return (GstMemory *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (memory));
}
/**
* gst_memory_unref:
* @memory: (transfer full): the memory to refcount
*
* Decrease the refcount of an memory, freeing it if the refcount reaches 0.
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC void gst_memory_unref (GstMemory * memory);
#endif
static inline void
gst_memory_unref (GstMemory * memory)
{
gst_mini_object_unref (GST_MINI_OBJECT_CAST (memory));
}
/* getting/setting memory properties */
gsize gst_memory_get_sizes (GstMemory *mem, gsize *offset, gsize *maxsize);
void gst_memory_resize (GstMemory *mem, gssize offset, gsize size);
#define gst_memory_lock(m,f) gst_mini_object_lock (GST_MINI_OBJECT_CAST (m), (f))
#define gst_memory_unlock(m,f) gst_mini_object_unlock (GST_MINI_OBJECT_CAST (m), (f))
#define gst_memory_is_writable(m) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (m))
#define gst_memory_make_writable(m) GST_MEMORY_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (m)))
/* retrieving data */
GstMemory * gst_memory_make_mapped (GstMemory *mem, GstMapInfo *info, GstMapFlags flags);
gboolean gst_memory_map (GstMemory *mem, GstMapInfo *info, GstMapFlags flags);
void gst_memory_unmap (GstMemory *mem, GstMapInfo *info);
/* copy and subregions */
GstMemory * gst_memory_copy (GstMemory *mem, gssize offset, gssize size);
GstMemory * gst_memory_share (GstMemory *mem, gssize offset, gssize size);
/* span memory */
gboolean gst_memory_is_span (GstMemory *mem1, GstMemory *mem2, gsize *offset);
G_END_DECLS
#endif /* __GST_MEMORY_H__ */