| /* GStreamer |
| * Copyright (C) 2011 Wim Taymans <wim.taymans@gmail.be> |
| * |
| * gstmemory.c: memory block handling |
| * |
| * 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. |
| */ |
| |
| /** |
| * SECTION:gstmemory |
| * @short_description: refcounted wrapper for memory blocks |
| * @see_also: #GstBuffer |
| * |
| * GstMemory is a lightweight refcounted object that wraps a region of memory. |
| * They are typically used to manage the data of a #GstBuffer. |
| * |
| * A GstMemory object has an allocated region of memory of maxsize. The maximum |
| * size does not change during the lifetime of the memory object. The memory |
| * also has an offset and size property that specifies the valid range of memory |
| * in the allocated region. |
| * |
| * Memory is usually created by allocators with a gst_allocator_alloc() |
| * method call. When NULL is used as the allocator, the default allocator will |
| * be used. |
| * |
| * New allocators can be registered with gst_allocator_register(). |
| * Allocators are identified by name and can be retrieved with |
| * gst_allocator_find(). gst_allocator_set_default() can be used to change the |
| * default allocator. |
| * |
| * New memory can be created with gst_memory_new_wrapped() that wraps the memory |
| * allocated elsewhere. |
| * |
| * Refcounting of the memory block is performed with gst_memory_ref() and |
| * gst_memory_unref(). |
| * |
| * The size of the memory can be retrieved and changed with |
| * gst_memory_get_sizes() and gst_memory_resize() respectively. |
| * |
| * Getting access to the data of the memory is performed with gst_memory_map(). |
| * The call will return a pointer to offset bytes into the region of memory. |
| * After the memory access is completed, gst_memory_unmap() should be called. |
| * |
| * Memory can be copied with gst_memory_copy(), which will return a writable |
| * copy. gst_memory_share() will create a new memory block that shares the |
| * memory with an existing memory block at a custom offset and with a custom |
| * size. |
| * |
| * Memory can be efficiently merged when gst_memory_is_span() returns TRUE. |
| * |
| * Last reviewed on 2012-03-28 (0.11.3) |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include "gst_private.h" |
| #include "gstmemory.h" |
| |
| #ifndef GST_DISABLE_TRACE |
| #include "gsttrace.h" |
| static GstAllocTrace *_gst_memory_trace; |
| static GstAllocTrace *_gst_allocator_trace; |
| #endif |
| |
| G_DEFINE_BOXED_TYPE (GstMemory, gst_memory, (GBoxedCopyFunc) gst_memory_ref, |
| (GBoxedFreeFunc) gst_memory_unref); |
| |
| G_DEFINE_BOXED_TYPE (GstAllocator, gst_allocator, |
| (GBoxedCopyFunc) gst_allocator_ref, (GBoxedFreeFunc) gst_allocator_unref); |
| |
| G_DEFINE_BOXED_TYPE (GstAllocationParams, gst_allocation_params, |
| (GBoxedCopyFunc) gst_allocation_params_copy, |
| (GBoxedFreeFunc) gst_allocation_params_free); |
| |
| #if defined(MEMORY_ALIGNMENT_MALLOC) |
| size_t gst_memory_alignment = 7; |
| #elif defined(MEMORY_ALIGNMENT_PAGESIZE) |
| /* we fill this in in the _init method */ |
| size_t gst_memory_alignment = 0; |
| #elif defined(MEMORY_ALIGNMENT) |
| size_t gst_memory_alignment = MEMORY_ALIGNMENT - 1; |
| #else |
| #error "No memory alignment configured" |
| size_t gst_memory_alignment = 0; |
| #endif |
| |
| struct _GstAllocator |
| { |
| gint refcount; |
| |
| GstMemoryInfo info; |
| |
| gpointer user_data; |
| GDestroyNotify notify; |
| }; |
| |
| /* default memory implementation */ |
| typedef struct |
| { |
| GstMemory mem; |
| gsize slice_size; |
| guint8 *data; |
| gpointer user_data; |
| GDestroyNotify notify; |
| } GstMemoryDefault; |
| |
| /* the default allocator */ |
| static GstAllocator *_default_allocator; |
| |
| /* our predefined allocators */ |
| static GstAllocator *_default_mem_impl; |
| |
| /* initialize the fields */ |
| static void |
| _default_mem_init (GstMemoryDefault * mem, GstMemoryFlags flags, |
| GstMemory * parent, gsize slice_size, gpointer data, |
| gsize maxsize, gsize offset, gsize size, gsize align, |
| gpointer user_data, GDestroyNotify notify) |
| { |
| mem->mem.allocator = _default_mem_impl; |
| mem->mem.flags = flags; |
| mem->mem.refcount = 1; |
| mem->mem.parent = parent ? gst_memory_ref (parent) : NULL; |
| mem->mem.state = (flags & GST_MEMORY_FLAG_READONLY ? 0x1 : 0); |
| mem->mem.maxsize = maxsize; |
| mem->mem.align = align; |
| mem->mem.offset = offset; |
| mem->mem.size = size; |
| mem->slice_size = slice_size; |
| mem->data = data; |
| mem->user_data = user_data; |
| mem->notify = notify; |
| |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "new memory %p, maxsize:%" G_GSIZE_FORMAT |
| " offset:%" G_GSIZE_FORMAT " size:%" G_GSIZE_FORMAT, mem, maxsize, |
| offset, size); |
| } |
| |
| /* create a new memory block that manages the given memory */ |
| static GstMemoryDefault * |
| _default_mem_new (GstMemoryFlags flags, GstMemory * parent, gpointer data, |
| gsize maxsize, gsize offset, gsize size, gsize align, gpointer user_data, |
| GDestroyNotify notify) |
| { |
| GstMemoryDefault *mem; |
| gsize slice_size; |
| |
| slice_size = sizeof (GstMemoryDefault); |
| |
| mem = g_slice_alloc (slice_size); |
| _default_mem_init (mem, flags, parent, slice_size, |
| data, maxsize, offset, size, align, user_data, notify); |
| |
| return mem; |
| } |
| |
| /* allocate the memory and structure in one block */ |
| static GstMemoryDefault * |
| _default_mem_new_block (GstMemoryFlags flags, gsize maxsize, gsize align, |
| gsize offset, gsize size) |
| { |
| GstMemoryDefault *mem; |
| gsize aoffset, slice_size, padding; |
| guint8 *data; |
| |
| /* ensure configured alignment */ |
| align |= gst_memory_alignment; |
| /* allocate more to compensate for alignment */ |
| maxsize += align; |
| /* alloc header and data in one block */ |
| slice_size = sizeof (GstMemoryDefault) + maxsize; |
| |
| mem = g_slice_alloc (slice_size); |
| if (mem == NULL) |
| return NULL; |
| |
| data = (guint8 *) mem + sizeof (GstMemoryDefault); |
| |
| /* do alignment */ |
| if ((aoffset = ((guintptr) data & align))) { |
| aoffset = (align + 1) - aoffset; |
| data += aoffset; |
| maxsize -= aoffset; |
| } |
| |
| if (offset && (flags & GST_MEMORY_FLAG_ZERO_PREFIXED)) |
| memset (data, 0, offset); |
| |
| padding = maxsize - (offset + size); |
| if (padding && (flags & GST_MEMORY_FLAG_ZERO_PADDED)) |
| memset (data + offset + size, 0, padding); |
| |
| _default_mem_init (mem, flags, NULL, slice_size, data, maxsize, |
| offset, size, align, NULL, NULL); |
| |
| return mem; |
| } |
| |
| static GstMemory * |
| _default_alloc_alloc (GstAllocator * allocator, gsize size, |
| GstAllocationParams * params, gpointer user_data) |
| { |
| gsize maxsize = size + params->prefix + params->padding; |
| |
| return (GstMemory *) _default_mem_new_block (params->flags, |
| maxsize, params->align, params->prefix, size); |
| } |
| |
| static gpointer |
| _default_mem_map (GstMemoryDefault * mem, GstMapFlags flags) |
| { |
| return mem->data; |
| } |
| |
| static gboolean |
| _default_mem_unmap (GstMemoryDefault * mem) |
| { |
| return TRUE; |
| } |
| |
| static void |
| _default_mem_free (GstMemoryDefault * mem) |
| { |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "free memory %p", mem); |
| |
| if (mem->mem.parent) |
| gst_memory_unref (mem->mem.parent); |
| |
| if (mem->notify) |
| mem->notify (mem->user_data); |
| |
| g_slice_free1 (mem->slice_size, mem); |
| } |
| |
| static GstMemoryDefault * |
| _default_mem_copy (GstMemoryDefault * mem, gssize offset, gsize size) |
| { |
| GstMemoryDefault *copy; |
| |
| if (size == -1) |
| size = mem->mem.size > offset ? mem->mem.size - offset : 0; |
| |
| copy = |
| _default_mem_new_block (0, mem->mem.maxsize, 0, mem->mem.offset + offset, |
| size); |
| memcpy (copy->data, mem->data, mem->mem.maxsize); |
| GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "copy memory %p -> %p", mem, copy); |
| |
| return copy; |
| } |
| |
| static GstMemoryDefault * |
| _default_mem_share (GstMemoryDefault * mem, gssize offset, gsize size) |
| { |
| GstMemoryDefault *sub; |
| GstMemory *parent; |
| |
| /* find the real parent */ |
| if ((parent = mem->mem.parent) == NULL) |
| parent = (GstMemory *) mem; |
| |
| if (size == -1) |
| size = mem->mem.size - offset; |
| |
| sub = |
| _default_mem_new (parent->flags, parent, mem->data, |
| mem->mem.maxsize, mem->mem.offset + offset, size, mem->mem.align, NULL, |
| NULL); |
| |
| return sub; |
| } |
| |
| static gboolean |
| _default_mem_is_span (GstMemoryDefault * mem1, GstMemoryDefault * mem2, |
| gsize * offset) |
| { |
| |
| if (offset) { |
| GstMemoryDefault *parent; |
| |
| parent = (GstMemoryDefault *) mem1->mem.parent; |
| |
| *offset = mem1->mem.offset - parent->mem.offset; |
| } |
| |
| /* and memory is contiguous */ |
| return mem1->data + mem1->mem.offset + mem1->mem.size == |
| mem2->data + mem2->mem.offset; |
| } |
| |
| static GstMemory * |
| _fallback_mem_copy (GstMemory * mem, gssize offset, gssize size) |
| { |
| GstMemory *copy; |
| GstMapInfo sinfo, dinfo; |
| GstAllocationParams params = { 0, 0, 0, mem->align, }; |
| |
| if (!gst_memory_map (mem, &sinfo, GST_MAP_READ)) |
| return NULL; |
| |
| if (size == -1) |
| size = sinfo.size > offset ? sinfo.size - offset : 0; |
| |
| /* use the same allocator as the memory we copy */ |
| copy = gst_allocator_alloc (mem->allocator, size, ¶ms); |
| if (!gst_memory_map (copy, &dinfo, GST_MAP_WRITE)) { |
| GST_CAT_WARNING (GST_CAT_MEMORY, "could not write map memory %p", copy); |
| gst_memory_unmap (mem, &sinfo); |
| return NULL; |
| } |
| |
| memcpy (dinfo.data, sinfo.data + offset, size); |
| GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "copy memory %p -> %p", mem, copy); |
| gst_memory_unmap (copy, &dinfo); |
| gst_memory_unmap (mem, &sinfo); |
| |
| return copy; |
| } |
| |
| static gboolean |
| _fallback_mem_is_span (GstMemory * mem1, GstMemory * mem2, gsize * offset) |
| { |
| return FALSE; |
| } |
| |
| static GRWLock lock; |
| static GHashTable *allocators; |
| |
| static void |
| _priv_sysmem_notify (gpointer user_data) |
| { |
| g_warning ("The default memory allocator was freed!"); |
| } |
| |
| void |
| _priv_gst_memory_initialize (void) |
| { |
| static const GstMemoryInfo _mem_info = { |
| GST_ALLOCATOR_SYSMEM, |
| (GstAllocatorAllocFunction) _default_alloc_alloc, |
| (GstMemoryMapFunction) _default_mem_map, |
| (GstMemoryUnmapFunction) _default_mem_unmap, |
| (GstMemoryFreeFunction) _default_mem_free, |
| (GstMemoryCopyFunction) _default_mem_copy, |
| (GstMemoryShareFunction) _default_mem_share, |
| (GstMemoryIsSpanFunction) _default_mem_is_span, |
| }; |
| |
| #ifndef GST_DISABLE_TRACE |
| _gst_memory_trace = _gst_alloc_trace_register ("GstMemory", -1); |
| _gst_allocator_trace = _gst_alloc_trace_register ("GstAllocator", -1); |
| #endif |
| |
| g_rw_lock_init (&lock); |
| allocators = g_hash_table_new (g_str_hash, g_str_equal); |
| |
| #ifdef HAVE_GETPAGESIZE |
| #ifdef MEMORY_ALIGNMENT_PAGESIZE |
| gst_memory_alignment = getpagesize () - 1; |
| #endif |
| #endif |
| |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "memory alignment: %" G_GSIZE_FORMAT, |
| gst_memory_alignment); |
| |
| _default_mem_impl = gst_allocator_new (&_mem_info, NULL, _priv_sysmem_notify); |
| |
| _default_allocator = gst_allocator_ref (_default_mem_impl); |
| gst_allocator_register (GST_ALLOCATOR_SYSMEM, |
| gst_allocator_ref (_default_mem_impl)); |
| } |
| |
| /** |
| * gst_memory_new_wrapped: |
| * @flags: #GstMemoryFlags |
| * @data: data to wrap |
| * @maxsize: allocated size of @data |
| * @offset: offset in @data |
| * @size: size of valid data |
| * @user_data: user_data |
| * @notify: called with @user_data when the memory is freed |
| * |
| * Allocate a new memory block that wraps the given @data. |
| * |
| * The prefix/padding must be filled with 0 if @flags contains |
| * #GST_MEMORY_FLAG_ZERO_PREFIXED and #GST_MEMORY_FLAG_ZERO_PADDED respectively. |
| * |
| * Returns: a new #GstMemory. |
| */ |
| GstMemory * |
| gst_memory_new_wrapped (GstMemoryFlags flags, gpointer data, |
| gsize maxsize, gsize offset, gsize size, gpointer user_data, |
| GDestroyNotify notify) |
| { |
| GstMemoryDefault *mem; |
| |
| g_return_val_if_fail (data != NULL, NULL); |
| g_return_val_if_fail (offset + size <= maxsize, NULL); |
| |
| mem = |
| _default_mem_new (flags, NULL, data, maxsize, offset, size, 0, user_data, |
| notify); |
| |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_new (_gst_memory_trace, mem); |
| #endif |
| |
| return (GstMemory *) mem; |
| } |
| |
| /** |
| * gst_memory_ref: |
| * @mem: a #GstMemory |
| * |
| * Increases the refcount of @mem. |
| * |
| * Returns: @mem with increased refcount |
| */ |
| GstMemory * |
| gst_memory_ref (GstMemory * mem) |
| { |
| g_return_val_if_fail (mem != NULL, NULL); |
| |
| GST_CAT_TRACE (GST_CAT_MEMORY, "memory %p, %d->%d", mem, mem->refcount, |
| mem->refcount + 1); |
| |
| g_atomic_int_inc (&mem->refcount); |
| |
| return mem; |
| } |
| |
| /** |
| * gst_memory_unref: |
| * @mem: a #GstMemory |
| * |
| * Decreases the refcount of @mem. When the refcount reaches 0, the free |
| * function of @mem will be called. |
| */ |
| void |
| gst_memory_unref (GstMemory * mem) |
| { |
| g_return_if_fail (mem != NULL); |
| g_return_if_fail (mem->allocator != NULL); |
| |
| GST_CAT_TRACE (GST_CAT_MEMORY, "memory %p, %d->%d", mem, mem->refcount, |
| mem->refcount - 1); |
| |
| if (g_atomic_int_dec_and_test (&mem->refcount)) { |
| /* there should be no outstanding mappings */ |
| g_return_if_fail (g_atomic_int_get (&mem->state) < 4); |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_free (_gst_memory_trace, mem); |
| #endif |
| mem->allocator->info.mem_free (mem); |
| } |
| } |
| |
| /** |
| * gst_memory_is_exclusive: |
| * @mem: a #GstMemory |
| * |
| * Check if the current ref to @mem is exclusive, this means that no other |
| * references exist other than @mem. |
| */ |
| gboolean |
| gst_memory_is_exclusive (GstMemory * mem) |
| { |
| g_return_val_if_fail (mem != NULL, FALSE); |
| |
| return (g_atomic_int_get (&mem->refcount) == 1); |
| } |
| |
| /** |
| * gst_memory_get_sizes: |
| * @mem: a #GstMemory |
| * @offset: pointer to offset |
| * @maxsize: pointer to maxsize |
| * |
| * Get the current @size, @offset and @maxsize of @mem. |
| * |
| * Returns: the current sizes of @mem |
| */ |
| gsize |
| gst_memory_get_sizes (GstMemory * mem, gsize * offset, gsize * maxsize) |
| { |
| g_return_val_if_fail (mem != NULL, 0); |
| |
| if (offset) |
| *offset = mem->offset; |
| if (maxsize) |
| *maxsize = mem->maxsize; |
| |
| return mem->size; |
| } |
| |
| /** |
| * gst_memory_resize: |
| * @mem: a #GstMemory |
| * @offset: a new offset |
| * @size: a new size |
| * |
| * Resize the memory region. @mem should be writable and offset + size should be |
| * less than the maxsize of @mem. |
| * |
| * #GST_MEMORY_FLAG_ZERO_PREFIXED and #GST_MEMORY_FLAG_ZERO_PADDED will be |
| * cleared when offset or padding is increased respectively. |
| */ |
| void |
| gst_memory_resize (GstMemory * mem, gssize offset, gsize size) |
| { |
| g_return_if_fail (mem != NULL); |
| g_return_if_fail (offset >= 0 || mem->offset >= -offset); |
| g_return_if_fail (size + mem->offset + offset <= mem->maxsize); |
| |
| /* if we increase the prefix, we can't guarantee it is still 0 filled */ |
| if ((offset > 0) && GST_MEMORY_IS_ZERO_PREFIXED (mem)) |
| GST_MEMORY_FLAG_UNSET (mem, GST_MEMORY_FLAG_ZERO_PREFIXED); |
| |
| /* if we increase the padding, we can't guarantee it is still 0 filled */ |
| if ((offset + size < mem->size) && GST_MEMORY_IS_ZERO_PADDED (mem)) |
| GST_MEMORY_FLAG_UNSET (mem, GST_MEMORY_FLAG_ZERO_PADDED); |
| |
| mem->offset += offset; |
| mem->size = size; |
| } |
| |
| static gboolean |
| gst_memory_lock (GstMemory * mem, GstMapFlags flags) |
| { |
| gint access_mode, state, newstate; |
| |
| access_mode = flags & 3; |
| |
| do { |
| state = g_atomic_int_get (&mem->state); |
| if (state == 0) { |
| /* nothing mapped, set access_mode and refcount */ |
| newstate = 4 | access_mode; |
| } else { |
| /* access_mode must match */ |
| if ((state & access_mode) != access_mode) |
| goto lock_failed; |
| /* increase refcount */ |
| newstate = state + 4; |
| } |
| } while (!g_atomic_int_compare_and_exchange (&mem->state, state, newstate)); |
| |
| return TRUE; |
| |
| lock_failed: |
| { |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "lock failed %p: state %d, access_mode %d", |
| mem, state, access_mode); |
| return FALSE; |
| } |
| } |
| |
| static void |
| gst_memory_unlock (GstMemory * mem) |
| { |
| gint state, newstate; |
| |
| do { |
| state = g_atomic_int_get (&mem->state); |
| /* decrease the refcount */ |
| newstate = state - 4; |
| /* last refcount, unset access_mode */ |
| if (newstate < 4) |
| newstate = 0; |
| } while (!g_atomic_int_compare_and_exchange (&mem->state, state, newstate)); |
| } |
| |
| |
| /** |
| * gst_memory_make_mapped: |
| * @mem: (transfer full): a #GstMemory |
| * @info: (out): pointer for info |
| * @flags: mapping flags |
| * |
| * Create a #GstMemory object that is mapped with @flags. If @mem is mappable |
| * with @flags, this function returns the mapped @mem directly. Otherwise a |
| * mapped copy of @mem is returned. |
| * |
| * This function takes ownership of old @mem and returns a reference to a new |
| * #GstMemory. |
| * |
| * Returns: (transfer full): a #GstMemory object mapped with @flags or NULL when |
| * a mapping is not possible. |
| */ |
| GstMemory * |
| gst_memory_make_mapped (GstMemory * mem, GstMapInfo * info, GstMapFlags flags) |
| { |
| GstMemory *result; |
| |
| if (gst_memory_map (mem, info, flags)) { |
| result = mem; |
| } else { |
| result = gst_memory_copy (mem, 0, -1); |
| gst_memory_unref (mem); |
| |
| if (result == NULL) |
| goto cannot_copy; |
| |
| if (!gst_memory_map (result, info, flags)) |
| goto cannot_map; |
| } |
| return result; |
| |
| /* ERRORS */ |
| cannot_copy: |
| { |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "cannot copy memory %p", mem); |
| return NULL; |
| } |
| cannot_map: |
| { |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "cannot map memory %p with flags %d", mem, |
| flags); |
| gst_memory_unref (result); |
| return NULL; |
| } |
| } |
| |
| /** |
| * gst_memory_map: |
| * @mem: a #GstMemory |
| * @info: (out): pointer for info |
| * @flags: mapping flags |
| * |
| * Fill @info with the pointer and sizes of the memory in @mem that can be |
| * accessed according to @flags. |
| * |
| * This function can return %FALSE for various reasons: |
| * - the memory backed by @mem is not accessible with the given @flags. |
| * - the memory was already mapped with a different mapping. |
| * |
| * @info and its contents remain valid for as long as @mem is valid and |
| * until gst_memory_unmap() is called. |
| * |
| * For each gst_memory_map() call, a corresponding gst_memory_unmap() call |
| * should be done. |
| * |
| * Returns: %TRUE if the map operation was successful. |
| */ |
| gboolean |
| gst_memory_map (GstMemory * mem, GstMapInfo * info, GstMapFlags flags) |
| { |
| g_return_val_if_fail (mem != NULL, FALSE); |
| g_return_val_if_fail (info != NULL, FALSE); |
| |
| if (!gst_memory_lock (mem, flags)) |
| goto lock_failed; |
| |
| info->data = mem->allocator->info.mem_map (mem, mem->maxsize, flags); |
| |
| if (G_UNLIKELY (info->data == NULL)) |
| goto error; |
| |
| info->memory = mem; |
| info->flags = flags; |
| info->size = mem->size; |
| info->maxsize = mem->maxsize - mem->offset; |
| info->data = info->data + mem->offset; |
| |
| return TRUE; |
| |
| /* ERRORS */ |
| lock_failed: |
| { |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "mem %p: lock %d failed", mem, flags); |
| return FALSE; |
| } |
| error: |
| { |
| /* something went wrong, restore the orginal state again */ |
| GST_CAT_ERROR (GST_CAT_MEMORY, "mem %p: map failed", mem); |
| gst_memory_unlock (mem); |
| return FALSE; |
| } |
| } |
| |
| /** |
| * gst_memory_unmap: |
| * @mem: a #GstMemory |
| * @info: a #GstMapInfo |
| * |
| * Release the memory obtained with gst_memory_map() |
| */ |
| void |
| gst_memory_unmap (GstMemory * mem, GstMapInfo * info) |
| { |
| g_return_if_fail (mem != NULL); |
| g_return_if_fail (info != NULL); |
| g_return_if_fail (info->memory == mem); |
| /* there must be a ref */ |
| g_return_if_fail (g_atomic_int_get (&mem->state) >= 4); |
| |
| mem->allocator->info.mem_unmap (mem); |
| gst_memory_unlock (mem); |
| } |
| |
| /** |
| * gst_memory_copy: |
| * @mem: a #GstMemory |
| * @offset: an offset to copy |
| * @size: size to copy or -1 to copy all bytes from offset |
| * |
| * Return a copy of @size bytes from @mem starting from @offset. This copy is |
| * guaranteed to be writable. @size can be set to -1 to return a copy all bytes |
| * from @offset. |
| * |
| * Returns: a new #GstMemory. |
| */ |
| GstMemory * |
| gst_memory_copy (GstMemory * mem, gssize offset, gssize size) |
| { |
| GstMemory *copy; |
| |
| g_return_val_if_fail (mem != NULL, NULL); |
| |
| copy = mem->allocator->info.mem_copy (mem, offset, size); |
| |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_new (_gst_memory_trace, copy); |
| #endif |
| |
| return copy; |
| } |
| |
| /** |
| * gst_memory_share: |
| * @mem: a #GstMemory |
| * @offset: an offset to share |
| * @size: size to share or -1 to share bytes from offset |
| * |
| * Return a shared copy of @size bytes from @mem starting from @offset. No |
| * memory copy is performed and the memory region is simply shared. The result |
| * is guaranteed to be not-writable. @size can be set to -1 to return a share |
| * all bytes from @offset. |
| * |
| * Returns: a new #GstMemory. |
| */ |
| GstMemory * |
| gst_memory_share (GstMemory * mem, gssize offset, gssize size) |
| { |
| GstMemory *shared; |
| |
| g_return_val_if_fail (mem != NULL, NULL); |
| g_return_val_if_fail (!GST_MEMORY_FLAG_IS_SET (mem, GST_MEMORY_FLAG_NO_SHARE), |
| NULL); |
| |
| shared = mem->allocator->info.mem_share (mem, offset, size); |
| |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_new (_gst_memory_trace, shared); |
| #endif |
| |
| return shared; |
| } |
| |
| /** |
| * gst_memory_is_span: |
| * @mem1: a #GstMemory |
| * @mem2: a #GstMemory |
| * @offset: a pointer to a result offset |
| * |
| * Check if @mem1 and mem2 share the memory with a common parent memory object |
| * and that the memory is contiguous. |
| * |
| * If this is the case, the memory of @mem1 and @mem2 can be merged |
| * efficiently by performing gst_memory_share() on the parent object from |
| * the returned @offset. |
| * |
| * Returns: %TRUE if the memory is contiguous and of a common parent. |
| */ |
| gboolean |
| gst_memory_is_span (GstMemory * mem1, GstMemory * mem2, gsize * offset) |
| { |
| g_return_val_if_fail (mem1 != NULL, FALSE); |
| g_return_val_if_fail (mem2 != NULL, FALSE); |
| |
| /* need to have the same allocators */ |
| if (mem1->allocator != mem2->allocator) |
| return FALSE; |
| |
| /* need to have the same parent */ |
| if (mem1->parent == NULL || mem1->parent != mem2->parent) |
| return FALSE; |
| |
| /* and memory is contiguous */ |
| if (!mem1->allocator->info.mem_is_span (mem1, mem2, offset)) |
| return FALSE; |
| |
| return TRUE; |
| } |
| |
| /** |
| * gst_allocator_new: |
| * @info: a #GstMemoryInfo |
| * @user_data: user data |
| * @notify: a #GDestroyNotify for @user_data |
| * |
| * Create a new memory allocator with @info and @user_data. |
| * |
| * All functions in @info are mandatory exept the copy and is_span |
| * functions, which will have a default implementation when left NULL. |
| * |
| * The @user_data will be passed to all calls of the alloc function. @notify |
| * will be called with @user_data when the allocator is freed. |
| * |
| * Returns: a new #GstAllocator. |
| */ |
| GstAllocator * |
| gst_allocator_new (const GstMemoryInfo * info, gpointer user_data, |
| GDestroyNotify notify) |
| { |
| GstAllocator *allocator; |
| |
| #define INSTALL_FALLBACK(_t) \ |
| if (allocator->info._t == NULL) allocator->info._t = _fallback_ ##_t; |
| |
| g_return_val_if_fail (info != NULL, NULL); |
| g_return_val_if_fail (info->alloc != NULL, NULL); |
| g_return_val_if_fail (info->mem_map != NULL, NULL); |
| g_return_val_if_fail (info->mem_unmap != NULL, NULL); |
| g_return_val_if_fail (info->mem_free != NULL, NULL); |
| g_return_val_if_fail (info->mem_share != NULL, NULL); |
| |
| allocator = g_slice_new (GstAllocator); |
| allocator->refcount = 1; |
| allocator->info = *info; |
| allocator->user_data = user_data; |
| allocator->notify = notify; |
| INSTALL_FALLBACK (mem_copy); |
| INSTALL_FALLBACK (mem_is_span); |
| #undef INSTALL_FALLBACK |
| |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "new allocator %p", allocator); |
| |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_new (_gst_allocator_trace, allocator); |
| #endif |
| |
| return allocator; |
| } |
| |
| /** |
| * gst_allocator_get_memory_type: |
| * @allocator: a #GstAllocator |
| * |
| * Get the memory type allocated by this allocator |
| * |
| * Returns: the memory type provided by @allocator |
| */ |
| const gchar * |
| gst_allocator_get_memory_type (GstAllocator * allocator) |
| { |
| g_return_val_if_fail (allocator != NULL, NULL); |
| |
| return allocator->info.mem_type; |
| } |
| |
| /** |
| * gst_allocator_ref: |
| * @allocator: a #GstAllocator |
| * |
| * Increases the refcount of @allocator. |
| * |
| * Returns: @allocator with increased refcount |
| */ |
| GstAllocator * |
| gst_allocator_ref (GstAllocator * allocator) |
| { |
| g_return_val_if_fail (allocator != NULL, NULL); |
| |
| GST_CAT_TRACE (GST_CAT_MEMORY, "allocator %p, %d->%d", allocator, |
| allocator->refcount, allocator->refcount + 1); |
| |
| g_atomic_int_inc (&allocator->refcount); |
| |
| return allocator; |
| } |
| |
| /** |
| * gst_allocator_unref: |
| * @allocator: a #GstAllocator |
| * |
| * Decreases the refcount of @allocator. When the refcount reaches 0, the notify |
| * function of @allocator will be called and the allocator will be freed. |
| */ |
| void |
| gst_allocator_unref (GstAllocator * allocator) |
| { |
| g_return_if_fail (allocator != NULL); |
| |
| GST_CAT_TRACE (GST_CAT_MEMORY, "allocator %p, %d->%d", allocator, |
| allocator->refcount, allocator->refcount - 1); |
| |
| if (g_atomic_int_dec_and_test (&allocator->refcount)) { |
| if (allocator->notify) |
| allocator->notify (allocator->user_data); |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_free (_gst_allocator_trace, allocator); |
| #endif |
| g_slice_free1 (sizeof (GstAllocator), allocator); |
| } |
| } |
| |
| /** |
| * gst_allocator_register: |
| * @name: the name of the allocator |
| * @allocator: (transfer full): #GstAllocator |
| * |
| * Registers the memory @allocator with @name. This function takes ownership of |
| * @allocator. |
| */ |
| void |
| gst_allocator_register (const gchar * name, GstAllocator * allocator) |
| { |
| g_return_if_fail (name != NULL); |
| g_return_if_fail (allocator != NULL); |
| |
| GST_CAT_DEBUG (GST_CAT_MEMORY, "registering allocator %p with name \"%s\"", |
| allocator, name); |
| |
| g_rw_lock_writer_lock (&lock); |
| g_hash_table_insert (allocators, (gpointer) name, (gpointer) allocator); |
| g_rw_lock_writer_unlock (&lock); |
| } |
| |
| /** |
| * gst_allocator_find: |
| * @name: the name of the allocator |
| * |
| * Find a previously registered allocator with @name. When @name is NULL, the |
| * default allocator will be returned. |
| * |
| * Returns: (transfer full): a #GstAllocator or NULL when the allocator with @name was not |
| * registered. Use gst_allocator_unref() to release the allocator after usage. |
| */ |
| GstAllocator * |
| gst_allocator_find (const gchar * name) |
| { |
| GstAllocator *allocator; |
| |
| g_rw_lock_reader_lock (&lock); |
| if (name) { |
| allocator = g_hash_table_lookup (allocators, (gconstpointer) name); |
| } else { |
| allocator = _default_allocator; |
| } |
| if (allocator) |
| gst_allocator_ref (allocator); |
| g_rw_lock_reader_unlock (&lock); |
| |
| return allocator; |
| } |
| |
| /** |
| * gst_allocator_set_default: |
| * @allocator: (transfer full): a #GstAllocator |
| * |
| * Set the default allocator. This function takes ownership of @allocator. |
| */ |
| void |
| gst_allocator_set_default (GstAllocator * allocator) |
| { |
| GstAllocator *old; |
| g_return_if_fail (allocator != NULL); |
| |
| g_rw_lock_writer_lock (&lock); |
| old = _default_allocator; |
| _default_allocator = allocator; |
| g_rw_lock_writer_unlock (&lock); |
| |
| if (old) |
| gst_allocator_unref (old); |
| } |
| |
| /** |
| * gst_allocation_params_init: |
| * @params: a #GstAllocationParams |
| * |
| * Initialize @params to its default values |
| */ |
| void |
| gst_allocation_params_init (GstAllocationParams * params) |
| { |
| g_return_if_fail (params != NULL); |
| |
| memset (params, 0, sizeof (GstAllocationParams)); |
| } |
| |
| /** |
| * gst_allocation_params_copy: |
| * @params: (transfer none): a #GstAllocationParams |
| * |
| * Create a copy of @params. |
| * |
| * Free-function: gst_allocation_params_free |
| * |
| * Returns: (transfer full): a new ##GstAllocationParams, free with |
| * gst_allocation_params_free(). |
| */ |
| GstAllocationParams * |
| gst_allocation_params_copy (const GstAllocationParams * params) |
| { |
| GstAllocationParams *result = NULL; |
| |
| if (params) { |
| result = |
| (GstAllocationParams *) g_slice_copy (sizeof (GstAllocationParams), |
| params); |
| } |
| return result; |
| } |
| |
| /** |
| * gst_allocation_params_free: |
| * @params: (in) (transfer full): a #GstAllocationParams |
| * |
| * Free @params |
| */ |
| void |
| gst_allocation_params_free (GstAllocationParams * params) |
| { |
| g_slice_free (GstAllocationParams, params); |
| } |
| |
| /** |
| * gst_allocator_alloc: |
| * @allocator: (transfer none) (allow-none): a #GstAllocator to use |
| * @size: size of the visible memory area |
| * @params: (transfer none) (allow-none): optional parameters |
| * |
| * Use @allocator to allocate a new memory block with memory that is at least |
| * @size big. |
| * |
| * The optional @params can specify the prefix and padding for the memory. If |
| * NULL is passed, no flags, no extra prefix/padding and a default alignment is |
| * used. |
| * |
| * The prefix/padding will be filled with 0 if flags contains |
| * #GST_MEMORY_FLAG_ZERO_PREFIXED and #GST_MEMORY_FLAG_ZERO_PADDED respectively. |
| * |
| * When @allocator is NULL, the default allocator will be used. |
| * |
| * The alignment in @params is given as a bitmask so that @align + 1 equals |
| * the amount of bytes to align to. For example, to align to 8 bytes, |
| * use an alignment of 7. |
| * |
| * Returns: (transfer full): a new #GstMemory. |
| */ |
| GstMemory * |
| gst_allocator_alloc (GstAllocator * allocator, gsize size, |
| GstAllocationParams * params) |
| { |
| GstMemory *mem; |
| static GstAllocationParams defparams = { 0, 0, 0, 0, }; |
| |
| if (params) { |
| g_return_val_if_fail (((params->align + 1) & params->align) == 0, NULL); |
| } else { |
| params = &defparams; |
| } |
| |
| if (allocator == NULL) |
| allocator = _default_allocator; |
| |
| mem = allocator->info.alloc (allocator, size, params, allocator->user_data); |
| |
| #ifndef GST_DISABLE_TRACE |
| _gst_alloc_trace_new (_gst_memory_trace, mem); |
| #endif |
| return mem; |
| } |