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design: memory: assorted formatting and markup fixes

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Reynaldo H. Verdejo Pinochet 2017-02-03 15:37:27 -08:00
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markdown/design/memory.md
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@ -12,13 +12,13 @@ multimedia data passed around in the pipeline.
## Memory layout ## Memory layout
`GstMemory` manages a memory region. The accessible part of the managed region is `GstMemory` manages a memory region. The accessible part of the managed region
defined by an offset relative to the start of the region and a size. This is defined by an offset relative to the start of the region and a size. This
means that the managed region can be larger than what is visible to the user of means that the managed region can be larger than what is visible to the user of
`GstMemory` API. `GstMemory` API.
Schematically, `GstMemory` has a pointer to a memory region of _maxsize_. The area Schematically, `GstMemory` has a pointer to a memory region of _maxsize_. The
starting from `offset` and `size` is accessible. area starting from `offset` and `size` is accessible.
``` ```
memory memory
@ -32,13 +32,13 @@ GstMemory ->*----------------------------------------------------*
The current properties of the accessible memory can be retrieved with: The current properties of the accessible memory can be retrieved with:
``` c ``` c
gsize gst_memory_get_sizes (GstMemory *mem, gsize *offset, gsize *maxsize); gsize gst_memory_get_sizes (GstMemory *mem, gsize *offset, gsize *maxsize);
``` ```
The offset and size can be changed with: The offset and size can be changed with:
``` c ``` c
void gst_memory_resize (GstMemory *mem, gssize offset, gsize size); void gst_memory_resize (GstMemory *mem, gssize offset, gsize size);
``` ```
## Allocators ## Allocators
@ -79,9 +79,8 @@ GStreamer system. This way, the allocator can be retrieved by name.
After an allocator is created, new `GstMemory` can be created with After an allocator is created, new `GstMemory` can be created with
``` c ``` c
GstMemory * gst_allocator_alloc (const GstAllocator * allocator, GstMemory * gst_allocator_alloc (const GstAllocator * allocator,
gsize size, gsize size, GstAllocationParams *params);
GstAllocationParams *params);
``` ```
`GstAllocationParams` contain extra info such as flags, alignment, prefix and `GstAllocationParams` contain extra info such as flags, alignment, prefix and
@ -99,11 +98,11 @@ It is also possible to create a new `GstMemory` object that wraps existing
memory with: memory with:
``` c ``` c
GstMemory * gst_memory_new_wrapped (GstMemoryFlags flags, GstMemory * gst_memory_new_wrapped (GstMemoryFlags flags,
gpointer data, gsize maxsize, gpointer data, gsize maxsize,
gsize offset, gsize size, gsize offset, gsize size,
gpointer user_data, gpointer user_data,
GDestroyNotify notify); GDestroyNotify notify);
``` ```
## Lifecycle ## Lifecycle
@ -131,16 +130,16 @@ After the data has been accessed in the object, the `unmap()` call must be
performed, which will unlock the memory again. performed, which will unlock the memory again.
It is allowed to recursively map multiple times with the same or narrower It is allowed to recursively map multiple times with the same or narrower
access modes. For each of the map calls, a corresponding unmap call needs to access modes. For each of the `map()` calls, a corresponding `unmap()` call
be made. WRITE-only memory cannot be mapped in READ mode and READ-only memory needs to be made. WRITE-only memory cannot be mapped in READ mode and
cannot be mapped in WRITE mode. READ-only memory cannot be mapped in WRITE mode.
The memory pointer returned from the map call is guaranteed to remain valid in The memory pointer returned from the `map()` call is guaranteed to remain
the requested mapping mode until the corresponding unmap call is performed on valid in the requested mapping mode until the corresponding `unmap()` call is
the pointer. performed on the pointer.
When multiple map operations are nested and return the same pointer, the pointer When multiple `map()` operations are nested and return the same pointer, the
is valid until the last unmap call is done. pointer is valid until the last `unmap()` call is done.
When the final reference on a memory object is dropped, all outstanding When the final reference on a memory object is dropped, all outstanding
mappings should have been unmapped. mappings should have been unmapped.