# 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.OH_NativeBuffer **起始版本:** 9 ## 汇总 ### 文件 | 名称 | 描述 | | -------- | -------- | | [native_buffer.h](native__buffer_8h.md) | 定义获取和使用NativeBuffer的相关函数。
引用文件:<native_buffer/native_buffer.h> | ### 结构体 | 名称 | 描述 | | -------- | -------- | | [OH_NativeBuffer_Config](_o_h___native_buffer___config.md) | 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](#oh_nativebuffer) | 提供OH_NativeBuffer结构体声明。 | ### 枚举 | 名称 | 描述 | | -------- | -------- | | [OH_NativeBuffer_Usage](#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](#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](#oh_nativebuffer_alloc) (const [OH_NativeBuffer_Config](_o_h___native_buffer___config.md) \*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_reference) ([OH_NativeBuffer](#oh_nativebuffer) \*buffer) | 将OH_NativeBuffer对象的引用计数加1。 | | [OH_NativeBuffer_Unreference](#oh_nativebuffer_unreference) ([OH_NativeBuffer](#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_getconfig) ([OH_NativeBuffer](#oh_nativebuffer) \*buffer, [OH_NativeBuffer_Config](_o_h___native_buffer___config.md) \*config) | 用于获取OH_NativeBuffer的属性。 | | [OH_NativeBuffer_Map](#oh_nativebuffer_map) ([OH_NativeBuffer](#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_unmap) ([OH_NativeBuffer](#oh_nativebuffer) \*buffer) | 将OH_NativeBuffer对应的ION内存从进程空间移除。 | | [OH_NativeBuffer_GetSeqNum](#oh_nativebuffer_getseqnum) ([OH_NativeBuffer](#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.OH_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.OH_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.OH_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.OH_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.OH_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.OH_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.OH_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。