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