OH_NativeBuffer
概述
提供NativeBuffer功能，通过提供的接口，可以实现共享内存的申请、使用、属性查询、释放等操作。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
起始版本:
9
汇总
文件
| 名称 | 描述 |
|---|---|
| native_buffer.h | 定义获取和使用NativeBuffer的相关函数。 引用文件： <native_buffer/native_buffer.h> 库： libnative_buffer.so |
结构体
| 名称 | 描述 |
|---|---|
| OH_NativeBuffer_Config | OH_NativeBuffer的属性配置，用于申请新的OH_NativeBuffer实例或查询现有实例的相关属性。 |
类型定义
| 名称 | 描述 |
|---|---|
| OH_NativeBuffer | 提供OH_NativeBuffer结构体声明。 |
枚举
| 名称 | 描述 |
|---|---|
| OH_NativeBuffer_Usage { NATIVEBUFFER_USAGE_CPU_READ = (1ULL << 0), NATIVEBUFFER_USAGE_CPU_WRITE = (1ULL << 1), NATIVEBUFFER_USAGE_MEM_DMA = (1ULL << 3) } | OH_NativeBuffer的用途。 |
| OH_NativeBuffer_Format { NATIVEBUFFER_PIXEL_FMT_RGB_565 = 3, NATIVEBUFFER_PIXEL_FMT_RGBA_5658, NATIVEBUFFER_PIXEL_FMT_RGBX_4444, NATIVEBUFFER_PIXEL_FMT_RGBA_4444, NATIVEBUFFER_PIXEL_FMT_RGB_444, NATIVEBUFFER_PIXEL_FMT_RGBX_5551, NATIVEBUFFER_PIXEL_FMT_RGBA_5551, NATIVEBUFFER_PIXEL_FMT_RGB_555, NATIVEBUFFER_PIXEL_FMT_RGBX_8888, NATIVEBUFFER_PIXEL_FMT_RGBA_8888, NATIVEBUFFER_PIXEL_FMT_RGB_888, NATIVEBUFFER_PIXEL_FMT_BGR_565, NATIVEBUFFER_PIXEL_FMT_BGRX_4444, NATIVEBUFFER_PIXEL_FMT_BGRA_4444, NATIVEBUFFER_PIXEL_FMT_BGRX_5551, NATIVEBUFFER_PIXEL_FMT_BGRA_5551, NATIVEBUFFER_PIXEL_FMT_BGRX_8888, NATIVEBUFFER_PIXEL_FMT_BGRA_8888, NATIVEBUFFER_PIXEL_FMT_BUTT = 0X7FFFFFFF } |
OH_NativeBuffer的格式。 |
函数
| 名称 | 描述 |
|---|---|
| OH_NativeBuffer_Alloc (const OH_NativeBuffer_Config *config) | 通过OH_NativeBuffer_Config创建OH_NativeBuffer实例，每次调用都会产生一个新的OH_NativeBuffer实例。 |
| OH_NativeBuffer_Reference (OH_NativeBuffer *buffer) | 将OH_NativeBuffer对象的引用计数加1。 |
| OH_NativeBuffer_Unreference (OH_NativeBuffer *buffer) | 将OH_NativeBuffer对象的引用计数减1，当引用计数为0的时候，该NativeBuffer对象会被析构掉。 |
| OH_NativeBuffer_GetConfig (OH_NativeBuffer *buffer, OH_NativeBuffer_Config *config) | 用于获取OH_NativeBuffer的属性。 |
| OH_NativeBuffer_Map (OH_NativeBuffer *buffer, void **virAddr) | 将OH_NativeBuffer对应的ION内存映射到进程空间。 |
| OH_NativeBuffer_Unmap (OH_NativeBuffer *buffer) | 将OH_NativeBuffer对应的ION内存从进程空间移除。 |
| OH_NativeBuffer_GetSeqNum (OH_NativeBuffer *buffer) | 获取OH_NativeBuffer的序列号。 |
类型定义说明
OH_NativeBuffer
typedef struct OH_NativeBuffer OH_NativeBuffer
描述:
提供OH_NativeBuffer结构体声明。
枚举类型说明
OH_NativeBuffer_Format
enum OH_NativeBuffer_Format
描述:
OH_NativeBuffer的格式。
@SysCap SystemCapability.Graphic.Graphic2D.NativeBuffer
| 枚举值 | 描述 |
|---|---|
| NATIVEBUFFER_PIXEL_FMT_RGB_565 | RGB565格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBA_5658 | RGBA5658格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBX_4444 | RGBX4444格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBA_4444 | RGBA4444格式 |
| NATIVEBUFFER_PIXEL_FMT_RGB_444 | RGB444格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBX_5551 | RGBX5551格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBA_5551 | RGBA5551格式 |
| NATIVEBUFFER_PIXEL_FMT_RGB_555 | RGB555格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBX_8888 | RGBX8888格式 |
| NATIVEBUFFER_PIXEL_FMT_RGBA_8888 | RGBA8888格式 |
| NATIVEBUFFER_PIXEL_FMT_RGB_888 | RGB888格式 |
| NATIVEBUFFER_PIXEL_FMT_BGR_565 | BGR565格式 |
| NATIVEBUFFER_PIXEL_FMT_BGRX_4444 | BGRX4444格式 |
| NATIVEBUFFER_PIXEL_FMT_BGRA_4444 | BGRA4444格式 |
| NATIVEBUFFER_PIXEL_FMT_BGRX_5551 | BGRX5551格式 |
| NATIVEBUFFER_PIXEL_FMT_BGRA_5551 | BGRA5551格式 |
| NATIVEBUFFER_PIXEL_FMT_BGRX_8888 | BGRX8888格式 |
| NATIVEBUFFER_PIXEL_FMT_BGRA_8888 | BGRA8888格式 |
| NATIVEBUFFER_PIXEL_FMT_BUTT | 无效格式 |
起始版本：
10
OH_NativeBuffer_Usage
enum OH_NativeBuffer_Usage
描述:
OH_NativeBuffer的用途。
@SysCap SystemCapability.Graphic.Graphic2D.NativeBuffer
| 枚举值 | 描述 |
|---|---|
| NATIVEBUFFER_USAGE_CPU_READ | CPU可读 |
| NATIVEBUFFER_USAGE_CPU_WRITE | CPU可写 |
| NATIVEBUFFER_USAGE_MEM_DMA | 直接内存访问缓冲区 |
起始版本：
10
函数说明
OH_NativeBuffer_Alloc()
OH_NativeBuffer* OH_NativeBuffer_Alloc (const OH_NativeBuffer_Config * config)
描述:
通过OH_NativeBuffer_Config创建OH_NativeBuffer实例，每次调用都会产生一个新的OH_NativeBuffer实例。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| config | 一个指向OH_NativeBuffer_Config类型的指针。 |
返回:
创建成功则返回一个指向OH_NativeBuffer结构体实例的指针，否则返回NULL。
OH_NativeBuffer_GetConfig()
void OH_NativeBuffer_GetConfig (OH_NativeBuffer * buffer, OH_NativeBuffer_Config * config )
描述:
用于获取OH_NativeBuffer的属性。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| buffer | 一个指向OH_NativeBuffer实例的指针。 |
| config | 一个指向OH_NativeBuffer_Config的指针，用于接收OH_NativeBuffer的属性。 |
OH_NativeBuffer_GetSeqNum()
uint32_t OH_NativeBuffer_GetSeqNum (OH_NativeBuffer * buffer)
描述:
获取OH_NativeBuffer的序列号。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| buffer | 一个指向OH_NativeBuffer实例的指针。 |
返回:
返回对应OH_NativeBuffer的唯一序列号。
OH_NativeBuffer_Map()
int32_t OH_NativeBuffer_Map (OH_NativeBuffer * buffer, void ** virAddr )
描述:
将OH_NativeBuffer对应的ION内存映射到进程空间。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| buffer | 一个指向OH_NativeBuffer实例的指针。 |
| virAddr | 一个二级指针，二级指针指向映射到当前进程的虚拟内存的地址。 |
返回:
返回值为0表示执行成功。
OH_NativeBuffer_Reference()
int32_t OH_NativeBuffer_Reference (OH_NativeBuffer * buffer)
描述:
将OH_NativeBuffer对象的引用计数加1。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| buffer | 一个指向OH_NativeBuffer实例的指针。 |
返回:
返回值为0表示执行成功。
OH_NativeBuffer_Unmap()
int32_t OH_NativeBuffer_Unmap (OH_NativeBuffer * buffer)
描述:
将OH_NativeBuffer对应的ION内存从进程空间移除。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| buffer | 一个指向OH_NativeBuffer实例的指针。 |
返回:
返回值为0表示执行成功。
OH_NativeBuffer_Unreference()
int32_t OH_NativeBuffer_Unreference (OH_NativeBuffer * buffer)
描述:
将OH_NativeBuffer对象的引用计数减1，当引用计数为0的时候，该NativeBuffer对象会被析构掉。
@syscap SystemCapability.Graphic.Graphic2D.NativeBuffer
参数:
| 名称 | 描述 |
|---|---|
| buffer | 一个指向OH_NativeBuffer实例的指针。 |
返回:
返回值为0表示执行成功。