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1 /*
2  * Copyright 2017 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 /**
18  * @file hardware_buffer.h
19  * @brief API for native hardware buffers.
20  */
21 /**
22  * @defgroup AHardwareBuffer Native Hardware Buffer
23  *
24  * AHardwareBuffer objects represent chunks of memory that can be
25  * accessed by various hardware components in the system. It can be
26  * easily converted to the Java counterpart
27  * android.hardware.HardwareBuffer and passed between processes using
28  * Binder. All operations involving AHardwareBuffer and HardwareBuffer
29  * are zero-copy, i.e., passing AHardwareBuffer to another process
30  * creates a shared view of the same region of memory.
31  *
32  * AHardwareBuffers can be bound to EGL/OpenGL and Vulkan primitives.
33  * For EGL, use the extension function eglGetNativeClientBufferANDROID
34  * to obtain an EGLClientBuffer and pass it directly to
35  * eglCreateImageKHR. Refer to the EGL extensions
36  * EGL_ANDROID_get_native_client_buffer and
37  * EGL_ANDROID_image_native_buffer for more information. In Vulkan,
38  * the contents of the AHardwareBuffer can be accessed as external
39  * memory. See the VK_ANDROID_external_memory_android_hardware_buffer
40  * extension for details.
41  *
42  * @{
43  */
44 
45 #ifndef ANDROID_HARDWARE_BUFFER_H
46 #define ANDROID_HARDWARE_BUFFER_H
47 
48 #include <android/rect.h>
49 #define ADATASPACE_SKIP_LEGACY_DEFINES
50 #include <android/data_space.h>
51 #undef ADATASPACE_SKIP_LEGACY_DEFINES
52 #include <inttypes.h>
53 #include <sys/cdefs.h>
54 
55 #if !defined(__INTRODUCED_IN)
56 #define __INTRODUCED_IN(__api_level) /* nothing */
57 #endif
58 
59 __BEGIN_DECLS
60 
61 // clang-format off
62 
63 /**
64  * Buffer pixel formats.
65  */
66 enum AHardwareBuffer_Format {
67     /**
68      * Corresponding formats:
69      *   Vulkan: VK_FORMAT_R8G8B8A8_UNORM
70      *   OpenGL ES: GL_RGBA8
71      */
72     AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM           = 1,
73 
74     /**
75      * 32 bits per pixel, 8 bits per channel format where alpha values are
76      * ignored (always opaque).
77      * Corresponding formats:
78      *   Vulkan: VK_FORMAT_R8G8B8A8_UNORM
79      *   OpenGL ES: GL_RGB8
80      */
81     AHARDWAREBUFFER_FORMAT_R8G8B8X8_UNORM           = 2,
82 
83     /**
84      * Corresponding formats:
85      *   Vulkan: VK_FORMAT_R8G8B8_UNORM
86      *   OpenGL ES: GL_RGB8
87      */
88     AHARDWAREBUFFER_FORMAT_R8G8B8_UNORM             = 3,
89 
90     /**
91      * Corresponding formats:
92      *   Vulkan: VK_FORMAT_R5G6B5_UNORM_PACK16
93      *   OpenGL ES: GL_RGB565
94      */
95     AHARDWAREBUFFER_FORMAT_R5G6B5_UNORM             = 4,
96 
97     /**
98      * Corresponding formats:
99      *   Vulkan: VK_FORMAT_R16G16B16A16_SFLOAT
100      *   OpenGL ES: GL_RGBA16F
101      */
102     AHARDWAREBUFFER_FORMAT_R16G16B16A16_FLOAT       = 0x16,
103 
104     /**
105      * Corresponding formats:
106      *   Vulkan: VK_FORMAT_A2B10G10R10_UNORM_PACK32
107      *   OpenGL ES: GL_RGB10_A2
108      */
109     AHARDWAREBUFFER_FORMAT_R10G10B10A2_UNORM        = 0x2b,
110 
111     /**
112      * Opaque binary blob format.
113      * Must have height 1 and one layer, with width equal to the buffer
114      * size in bytes. Corresponds to Vulkan buffers and OpenGL buffer
115      * objects. Can be bound to the latter using GL_EXT_external_buffer.
116      */
117     AHARDWAREBUFFER_FORMAT_BLOB                     = 0x21,
118 
119     /**
120      * Corresponding formats:
121      *   Vulkan: VK_FORMAT_D16_UNORM
122      *   OpenGL ES: GL_DEPTH_COMPONENT16
123      */
124     AHARDWAREBUFFER_FORMAT_D16_UNORM                = 0x30,
125 
126     /**
127      * Corresponding formats:
128      *   Vulkan: VK_FORMAT_X8_D24_UNORM_PACK32
129      *   OpenGL ES: GL_DEPTH_COMPONENT24
130      */
131     AHARDWAREBUFFER_FORMAT_D24_UNORM                = 0x31,
132 
133     /**
134      * Corresponding formats:
135      *   Vulkan: VK_FORMAT_D24_UNORM_S8_UINT
136      *   OpenGL ES: GL_DEPTH24_STENCIL8
137      */
138     AHARDWAREBUFFER_FORMAT_D24_UNORM_S8_UINT        = 0x32,
139 
140     /**
141      * Corresponding formats:
142      *   Vulkan: VK_FORMAT_D32_SFLOAT
143      *   OpenGL ES: GL_DEPTH_COMPONENT32F
144      */
145     AHARDWAREBUFFER_FORMAT_D32_FLOAT                = 0x33,
146 
147     /**
148      * Corresponding formats:
149      *   Vulkan: VK_FORMAT_D32_SFLOAT_S8_UINT
150      *   OpenGL ES: GL_DEPTH32F_STENCIL8
151      */
152     AHARDWAREBUFFER_FORMAT_D32_FLOAT_S8_UINT        = 0x34,
153 
154     /**
155      * Corresponding formats:
156      *   Vulkan: VK_FORMAT_S8_UINT
157      *   OpenGL ES: GL_STENCIL_INDEX8
158      */
159     AHARDWAREBUFFER_FORMAT_S8_UINT                  = 0x35,
160 
161     /**
162      * YUV 420 888 format.
163      * Must have an even width and height. Can be accessed in OpenGL
164      * shaders through an external sampler. Does not support mip-maps
165      * cube-maps or multi-layered textures.
166      */
167     AHARDWAREBUFFER_FORMAT_Y8Cb8Cr8_420             = 0x23,
168 
169     /**
170      * YUV P010 format.
171      * Must have an even width and height. Can be accessed in OpenGL
172      * shaders through an external sampler. Does not support mip-maps
173      * cube-maps or multi-layered textures.
174      */
175     AHARDWAREBUFFER_FORMAT_YCbCr_P010               = 0x36,
176 
177     /**
178      * Corresponding formats:
179      *   Vulkan: VK_FORMAT_R8_UNORM
180      *   OpenGL ES: GR_GL_R8
181      */
182     AHARDWAREBUFFER_FORMAT_R8_UNORM                 = 0x38,
183 
184     /**
185      * Corresponding formats:
186      *   Vulkan: VK_FORMAT_R16_UINT
187      *   OpenGL ES: GL_R16UI
188      */
189     AHARDWAREBUFFER_FORMAT_R16_UINT                 = 0x39,
190 
191     /**
192      * Corresponding formats:
193      *   Vulkan: VK_FORMAT_R16G16_UINT
194      *   OpenGL ES: GL_RG16UI
195      */
196     AHARDWAREBUFFER_FORMAT_R16G16_UINT              = 0x3a,
197 
198     /**
199      * Corresponding formats:
200      *   Vulkan: VK_FORMAT_R10X6G10X6B10X6A10X6_UNORM_4PACK16
201      *   OpenGL ES: N/A
202      */
203     AHARDWAREBUFFER_FORMAT_R10G10B10A10_UNORM       = 0x3b,
204 };
205 
206 /**
207  * Buffer usage flags, specifying how the buffer will be accessed.
208  */
209 enum AHardwareBuffer_UsageFlags {
210     /**
211      * The buffer will never be locked for direct CPU reads using the
212      * AHardwareBuffer_lock() function. Note that reading the buffer
213      * using OpenGL or Vulkan functions or memory mappings is still
214      * allowed.
215      */
216     AHARDWAREBUFFER_USAGE_CPU_READ_NEVER        = 0UL,
217     /**
218      * The buffer will sometimes be locked for direct CPU reads using
219      * the AHardwareBuffer_lock() function. Note that reading the
220      * buffer using OpenGL or Vulkan functions or memory mappings
221      * does not require the presence of this flag.
222      */
223     AHARDWAREBUFFER_USAGE_CPU_READ_RARELY       = 2UL,
224     /**
225      * The buffer will often be locked for direct CPU reads using
226      * the AHardwareBuffer_lock() function. Note that reading the
227      * buffer using OpenGL or Vulkan functions or memory mappings
228      * does not require the presence of this flag.
229      */
230     AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN        = 3UL,
231 
232     /** CPU read value mask. */
233     AHARDWAREBUFFER_USAGE_CPU_READ_MASK         = 0xFUL,
234     /**
235      * The buffer will never be locked for direct CPU writes using the
236      * AHardwareBuffer_lock() function. Note that writing the buffer
237      * using OpenGL or Vulkan functions or memory mappings is still
238      * allowed.
239      */
240     AHARDWAREBUFFER_USAGE_CPU_WRITE_NEVER       = 0UL << 4,
241     /**
242      * The buffer will sometimes be locked for direct CPU writes using
243      * the AHardwareBuffer_lock() function. Note that writing the
244      * buffer using OpenGL or Vulkan functions or memory mappings
245      * does not require the presence of this flag.
246      */
247     AHARDWAREBUFFER_USAGE_CPU_WRITE_RARELY      = 2UL << 4,
248     /**
249      * The buffer will often be locked for direct CPU writes using
250      * the AHardwareBuffer_lock() function. Note that writing the
251      * buffer using OpenGL or Vulkan functions or memory mappings
252      * does not require the presence of this flag.
253      */
254     AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN       = 3UL << 4,
255     /** CPU write value mask. */
256     AHARDWAREBUFFER_USAGE_CPU_WRITE_MASK        = 0xFUL << 4,
257     /** The buffer will be read from by the GPU as a texture. */
258     AHARDWAREBUFFER_USAGE_GPU_SAMPLED_IMAGE     = 1UL << 8,
259     /** The buffer will be written to by the GPU as a framebuffer attachment.*/
260     AHARDWAREBUFFER_USAGE_GPU_FRAMEBUFFER       = 1UL << 9,
261     /**
262      * The buffer will be written to by the GPU as a framebuffer
263      * attachment.
264      *
265      * Note that the name of this flag is somewhat misleading: it does
266      * not imply that the buffer contains a color format. A buffer with
267      * depth or stencil format that will be used as a framebuffer
268      * attachment should also have this flag. Use the equivalent flag
269      * AHARDWAREBUFFER_USAGE_GPU_FRAMEBUFFER to avoid this confusion.
270      */
271     AHARDWAREBUFFER_USAGE_GPU_COLOR_OUTPUT      = AHARDWAREBUFFER_USAGE_GPU_FRAMEBUFFER,
272     /**
273      * The buffer will be used as a composer HAL overlay layer.
274      *
275      * This flag is currently only needed when using ASurfaceTransaction_setBuffer
276      * to set a buffer. In all other cases, the framework adds this flag
277      * internally to buffers that could be presented in a composer overlay.
278      * ASurfaceTransaction_setBuffer is special because it uses buffers allocated
279      * directly through AHardwareBuffer_allocate instead of buffers allocated
280      * by the framework.
281      */
282     AHARDWAREBUFFER_USAGE_COMPOSER_OVERLAY      = 1ULL << 11,
283     /**
284      * The buffer is protected from direct CPU access or being read by
285      * non-secure hardware, such as video encoders.
286      *
287      * This flag is incompatible with CPU read and write flags. It is
288      * mainly used when handling DRM video. Refer to the EGL extension
289      * EGL_EXT_protected_content and GL extension
290      * GL_EXT_protected_textures for more information on how these
291      * buffers are expected to behave.
292      */
293     AHARDWAREBUFFER_USAGE_PROTECTED_CONTENT     = 1UL << 14,
294     /** The buffer will be read by a hardware video encoder. */
295     AHARDWAREBUFFER_USAGE_VIDEO_ENCODE          = 1UL << 16,
296     /**
297      * The buffer will be used for direct writes from sensors.
298      * When this flag is present, the format must be AHARDWAREBUFFER_FORMAT_BLOB.
299      */
300     AHARDWAREBUFFER_USAGE_SENSOR_DIRECT_DATA    = 1UL << 23,
301     /**
302      * The buffer will be used as a shader storage or uniform buffer object.
303      * When this flag is present, the format must be AHARDWAREBUFFER_FORMAT_BLOB.
304      */
305     AHARDWAREBUFFER_USAGE_GPU_DATA_BUFFER       = 1UL << 24,
306     /**
307      * The buffer will be used as a cube map texture.
308      * When this flag is present, the buffer must have a layer count
309      * that is a multiple of 6. Note that buffers with this flag must be
310      * bound to OpenGL textures using the extension
311      * GL_EXT_EGL_image_storage instead of GL_KHR_EGL_image.
312      */
313     AHARDWAREBUFFER_USAGE_GPU_CUBE_MAP          = 1UL << 25,
314     /**
315      * The buffer contains a complete mipmap hierarchy.
316      * Note that buffers with this flag must be bound to OpenGL textures using
317      * the extension GL_EXT_EGL_image_storage instead of GL_KHR_EGL_image.
318      */
319     AHARDWAREBUFFER_USAGE_GPU_MIPMAP_COMPLETE   = 1UL << 26,
320 
321     /**
322      * Usage: The buffer is used for front-buffer rendering. When
323      * front-buffering rendering is specified, different usages may adjust their
324      * behavior as a result. For example, when used as GPU_COLOR_OUTPUT the buffer
325      * will behave similar to a single-buffered window. When used with
326      * COMPOSER_OVERLAY, the system will try to prioritize the buffer receiving
327      * an overlay plane & avoid caching it in intermediate composition buffers.
328      */
329     AHARDWAREBUFFER_USAGE_FRONT_BUFFER = 1UL << 32,
330 
331     AHARDWAREBUFFER_USAGE_VENDOR_0  = 1ULL << 28,
332     AHARDWAREBUFFER_USAGE_VENDOR_1  = 1ULL << 29,
333     AHARDWAREBUFFER_USAGE_VENDOR_2  = 1ULL << 30,
334     AHARDWAREBUFFER_USAGE_VENDOR_3  = 1ULL << 31,
335     AHARDWAREBUFFER_USAGE_VENDOR_4  = 1ULL << 48,
336     AHARDWAREBUFFER_USAGE_VENDOR_5  = 1ULL << 49,
337     AHARDWAREBUFFER_USAGE_VENDOR_6  = 1ULL << 50,
338     AHARDWAREBUFFER_USAGE_VENDOR_7  = 1ULL << 51,
339     AHARDWAREBUFFER_USAGE_VENDOR_8  = 1ULL << 52,
340     AHARDWAREBUFFER_USAGE_VENDOR_9  = 1ULL << 53,
341     AHARDWAREBUFFER_USAGE_VENDOR_10 = 1ULL << 54,
342     AHARDWAREBUFFER_USAGE_VENDOR_11 = 1ULL << 55,
343     AHARDWAREBUFFER_USAGE_VENDOR_12 = 1ULL << 56,
344     AHARDWAREBUFFER_USAGE_VENDOR_13 = 1ULL << 57,
345     AHARDWAREBUFFER_USAGE_VENDOR_14 = 1ULL << 58,
346     AHARDWAREBUFFER_USAGE_VENDOR_15 = 1ULL << 59,
347     AHARDWAREBUFFER_USAGE_VENDOR_16 = 1ULL << 60,
348     AHARDWAREBUFFER_USAGE_VENDOR_17 = 1ULL << 61,
349     AHARDWAREBUFFER_USAGE_VENDOR_18 = 1ULL << 62,
350     AHARDWAREBUFFER_USAGE_VENDOR_19 = 1ULL << 63,
351 };
352 
353 /**
354  * Buffer description. Used for allocating new buffers and querying
355  * parameters of existing ones.
356  */
357 typedef struct AHardwareBuffer_Desc {
358     uint32_t width;  ///< Width in pixels.
359     uint32_t height; ///< Height in pixels.
360     /**
361      * Number of images in an image array. AHardwareBuffers with one
362      * layer correspond to regular 2D textures. AHardwareBuffers with
363      * more than layer correspond to texture arrays. If the layer count
364      * is a multiple of 6 and the usage flag
365      * AHARDWAREBUFFER_USAGE_GPU_CUBE_MAP is present, the buffer is
366      * a cube map or a cube map array.
367      */
368     uint32_t layers;
369     uint32_t format; ///< One of AHardwareBuffer_Format.
370     uint64_t usage;  ///< Combination of AHardwareBuffer_UsageFlags.
371     uint32_t stride; ///< Row stride in pixels, ignored for AHardwareBuffer_allocate()
372     uint32_t rfu0;   ///< Initialize to zero, reserved for future use.
373     uint64_t rfu1;   ///< Initialize to zero, reserved for future use.
374 } AHardwareBuffer_Desc;
375 
376 /**
377  * Holds data for a single image plane.
378  */
379 typedef struct AHardwareBuffer_Plane {
380     void*    _Nullable data; ///< Points to first byte in plane
381     uint32_t pixelStride;    ///< Distance in bytes from the color channel of one pixel to the next
382     uint32_t rowStride;      ///< Distance in bytes from the first value of one row of the image to
383                              ///  the first value of the next row.
384 } AHardwareBuffer_Plane;
385 
386 /**
387  * Holds all image planes that contain the pixel data.
388  */
389 typedef struct AHardwareBuffer_Planes {
390     uint32_t              planeCount; ///< Number of distinct planes
391     AHardwareBuffer_Plane planes[4];  ///< Array of image planes
392 } AHardwareBuffer_Planes;
393 
394 /**
395  * Opaque handle for a native hardware buffer.
396  */
397 typedef struct AHardwareBuffer AHardwareBuffer;
398 
399 // clang-format on
400 
401 /**
402  * Allocates a buffer that matches the passed AHardwareBuffer_Desc.
403  *
404  * If allocation succeeds, the buffer can be used according to the
405  * usage flags specified in its description. If a buffer is used in ways
406  * not compatible with its usage flags, the results are undefined and
407  * may include program termination.
408  *
409  * Available since API level 26.
410  *
411  * \return 0 on success, or an error number of the allocation fails for
412  * any reason. The returned buffer has a reference count of 1.
413  */
414 int AHardwareBuffer_allocate(const AHardwareBuffer_Desc* _Nonnull desc,
415                              AHardwareBuffer* _Nullable* _Nonnull outBuffer) __INTRODUCED_IN(26);
416 /**
417  * Acquire a reference on the given AHardwareBuffer object.
418  *
419  * This prevents the object from being deleted until the last reference
420  * is removed.
421  *
422  * Available since API level 26.
423  */
424 void AHardwareBuffer_acquire(AHardwareBuffer* _Nonnull buffer) __INTRODUCED_IN(26);
425 
426 /**
427  * Remove a reference that was previously acquired with
428  * AHardwareBuffer_acquire() or AHardwareBuffer_allocate().
429  *
430  * Available since API level 26.
431  */
432 void AHardwareBuffer_release(AHardwareBuffer* _Nonnull buffer) __INTRODUCED_IN(26);
433 
434 /**
435  * Return a description of the AHardwareBuffer in the passed
436  * AHardwareBuffer_Desc struct.
437  *
438  * Available since API level 26.
439  */
440 void AHardwareBuffer_describe(const AHardwareBuffer* _Nonnull buffer,
441                               AHardwareBuffer_Desc* _Nonnull outDesc) __INTRODUCED_IN(26);
442 
443 /**
444  * Lock the AHardwareBuffer for direct CPU access.
445  *
446  * This function can lock the buffer for either reading or writing.
447  * It may block if the hardware needs to finish rendering, if CPU caches
448  * need to be synchronized, or possibly for other implementation-
449  * specific reasons.
450  *
451  * The passed AHardwareBuffer must have one layer, otherwise the call
452  * will fail.
453  *
454  * If \a fence is not negative, it specifies a fence file descriptor on
455  * which to wait before locking the buffer. If it's negative, the caller
456  * is responsible for ensuring that writes to the buffer have completed
457  * before calling this function.  Using this parameter is more efficient
458  * than waiting on the fence and then calling this function.
459  *
460  * The \a usage parameter may only specify AHARDWAREBUFFER_USAGE_CPU_*.
461  * If set, then outVirtualAddress is filled with the address of the
462  * buffer in virtual memory. The flags must also be compatible with
463  * usage flags specified at buffer creation: if a read flag is passed,
464  * the buffer must have been created with
465  * AHARDWAREBUFFER_USAGE_CPU_READ_RARELY or
466  * AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN. If a write flag is passed, it
467  * must have been created with AHARDWAREBUFFER_USAGE_CPU_WRITE_RARELY or
468  * AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN.
469  *
470  * If \a rect is not NULL, the caller promises to modify only data in
471  * the area specified by rect. If rect is NULL, the caller may modify
472  * the contents of the entire buffer. The content of the buffer outside
473  * of the specified rect is NOT modified by this call.
474  *
475  * It is legal for several different threads to lock a buffer for read
476  * access; none of the threads are blocked.
477  *
478  * Locking a buffer simultaneously for write or read/write is undefined,
479  * but will neither terminate the process nor block the caller.
480  * AHardwareBuffer_lock may return an error or leave the buffer's
481  * content in an indeterminate state.
482  *
483  * If the buffer has AHARDWAREBUFFER_FORMAT_BLOB, it is legal lock it
484  * for reading and writing in multiple threads and/or processes
485  * simultaneously, and the contents of the buffer behave like shared
486  * memory.
487  *
488  * Available since API level 26.
489  *
490  * \return 0 on success. -EINVAL if \a buffer is NULL, the usage flags
491  * are not a combination of AHARDWAREBUFFER_USAGE_CPU_*, or the buffer
492  * has more than one layer. Error number if the lock fails for any other
493  * reason.
494  */
495 int AHardwareBuffer_lock(AHardwareBuffer* _Nonnull buffer, uint64_t usage, int32_t fence,
496                          const ARect* _Nullable rect, void* _Nullable* _Nonnull outVirtualAddress)
497         __INTRODUCED_IN(26);
498 
499 /**
500  * Unlock the AHardwareBuffer from direct CPU access.
501  *
502  * Must be called after all changes to the buffer are completed by the
503  * caller.  If \a fence is NULL, the function will block until all work
504  * is completed.  Otherwise, \a fence will be set either to a valid file
505  * descriptor or to -1.  The file descriptor will become signaled once
506  * the unlocking is complete and buffer contents are updated.
507  * The caller is responsible for closing the file descriptor once it's
508  * no longer needed.  The value -1 indicates that unlocking has already
509  * completed before the function returned and no further operations are
510  * necessary.
511  *
512  * Available since API level 26.
513  *
514  * \return 0 on success. -EINVAL if \a buffer is NULL. Error number if
515  * the unlock fails for any reason.
516  */
517 int AHardwareBuffer_unlock(AHardwareBuffer* _Nonnull buffer, int32_t* _Nullable fence)
518         __INTRODUCED_IN(26);
519 
520 /**
521  * Send the AHardwareBuffer to an AF_UNIX socket.
522  *
523  * Available since API level 26.
524  *
525  * \return 0 on success, -EINVAL if \a buffer is NULL, or an error
526  * number if the operation fails for any reason.
527  */
528 int AHardwareBuffer_sendHandleToUnixSocket(const AHardwareBuffer* _Nonnull buffer, int socketFd)
529         __INTRODUCED_IN(26);
530 
531 /**
532  * Receive an AHardwareBuffer from an AF_UNIX socket.
533  *
534  * Available since API level 26.
535  *
536  * \return 0 on success, -EINVAL if \a outBuffer is NULL, or an error
537  * number if the operation fails for any reason.
538  */
539 int AHardwareBuffer_recvHandleFromUnixSocket(int socketFd,
540                                              AHardwareBuffer* _Nullable* _Nonnull outBuffer)
541         __INTRODUCED_IN(26);
542 
543 /**
544  * Lock a potentially multi-planar AHardwareBuffer for direct CPU access.
545  *
546  * This function is similar to AHardwareBuffer_lock, but can lock multi-planar
547  * formats. The locked planes are returned in the \a outPlanes argument. Note,
548  * that multi-planar should not be confused with multi-layer images, which this
549  * locking function does not support.
550  *
551  * YUV formats are always represented by three separate planes of data, one for
552  * each color plane. The order of planes in the array is guaranteed such that
553  * plane #0 is always Y, plane #1 is always U (Cb), and plane #2 is always V
554  * (Cr). All other formats are represented by a single plane.
555  *
556  * Additional information always accompanies the buffers, describing the row
557  * stride and the pixel stride for each plane.
558  *
559  * In case the buffer cannot be locked, \a outPlanes will contain zero planes.
560  *
561  * See the AHardwareBuffer_lock documentation for all other locking semantics.
562  *
563  * Available since API level 29.
564  *
565  * \return 0 on success. -EINVAL if \a buffer is NULL, the usage flags
566  * are not a combination of AHARDWAREBUFFER_USAGE_CPU_*, or the buffer
567  * has more than one layer. Error number if the lock fails for any other
568  * reason.
569  */
570 int AHardwareBuffer_lockPlanes(AHardwareBuffer* _Nonnull buffer, uint64_t usage, int32_t fence,
571                                const ARect* _Nullable rect,
572                                AHardwareBuffer_Planes* _Nonnull outPlanes) __INTRODUCED_IN(29);
573 
574 /**
575  * Test whether the given format and usage flag combination is
576  * allocatable.
577  *
578  * If this function returns true, it means that a buffer with the given
579  * description can be allocated on this implementation, unless resource
580  * exhaustion occurs. If this function returns false, it means that the
581  * allocation of the given description will never succeed.
582  *
583  * The return value of this function may depend on all fields in the
584  * description, except stride, which is always ignored. For example,
585  * some implementations have implementation-defined limits on texture
586  * size and layer count.
587  *
588  * Available since API level 29.
589  *
590  * \return 1 if the format and usage flag combination is allocatable,
591  *     0 otherwise.
592  */
593 int AHardwareBuffer_isSupported(const AHardwareBuffer_Desc* _Nonnull desc) __INTRODUCED_IN(29);
594 
595 /**
596  * Lock an AHardwareBuffer for direct CPU access.
597  *
598  * This function is the same as the above lock function, but passes back
599  * additional information about the bytes per pixel and the bytes per stride
600  * of the locked buffer.  If the bytes per pixel or bytes per stride are unknown
601  * or variable, or if the underlying mapper implementation does not support returning
602  * additional information, then this call will fail with INVALID_OPERATION
603  *
604  * Available since API level 29.
605  */
606 int AHardwareBuffer_lockAndGetInfo(AHardwareBuffer* _Nonnull buffer, uint64_t usage, int32_t fence,
607                                    const ARect* _Nullable rect,
608                                    void* _Nullable* _Nonnull outVirtualAddress,
609                                    int32_t* _Nonnull outBytesPerPixel,
610                                    int32_t* _Nonnull outBytesPerStride) __INTRODUCED_IN(29);
611 
612 
613 /**
614  * Get the system wide unique id for an AHardwareBuffer.
615  *
616  * Available since API level 31.
617  *
618  * \return 0 on success, -EINVAL if \a buffer or \a outId is NULL, or an error number if the
619  * operation fails for any reason.
620  */
621 int AHardwareBuffer_getId(const AHardwareBuffer* _Nonnull buffer, uint64_t* _Nonnull outId)
622         __INTRODUCED_IN(31);
623 
624 __END_DECLS
625 
626 #endif // ANDROID_HARDWARE_BUFFER_H
627 
628 /** @} */
629