Rawfile
Overview
Provides the function of operating rawfile directories and rawfiles.
These functions include traversing, opening, searching, reading, and closing rawfiles.
Since: 8
Summary
Files
| Name | Description |
|---|---|
| raw_dir.h | Provides functions for operating rawfile directories. File to Include: <rawfile/raw_dir.h> |
| raw_file.h | Provides functions for operating rawfiles. File to Include: <rawfile/raw_file.h> |
| raw_file_manager.h | Provides functions for managing rawfile resources. File to Include: <rawfile/raw_file_manager.h> |
Structs
| Name | Description |
|---|---|
| RawFileDescriptor | Provides rawfile descriptor information. |
Types
| Name | Description |
|---|---|
| RawDir | Provides the function of accessing rawfile directories. |
| RawFile | Provides the function of accessing rawfiles. |
| NativeResourceManager | Implements the resource manager. |
Functions
| Name | Description |
|---|---|
| OH_ResourceManager_GetRawFileName (RawDir *rawDir, int index) | Obtains the rawfile name via an index. |
| OH_ResourceManager_GetRawFileCount (RawDir *rawDir) | Obtains the number of rawfiles in RawDir. |
| OH_ResourceManager_CloseRawDir (RawDir *rawDir) | Closes an opened RawDir and releases all associated resources. |
| OH_ResourceManager_ReadRawFile (const RawFile *rawFile, void *buf, size_t length) | Reads a rawfile. |
| OH_ResourceManager_SeekRawFile (const RawFile *rawFile, long offset, int whence) | Seeks for the data read/write position in the rawfile based on the specified offset. |
| OH_ResourceManager_GetRawFileSize (RawFile *rawFile) | Obtains the length of a rawfile in int32_t. |
| OH_ResourceManager_CloseRawFile (RawFile *rawFile) | Closes an opened RawFile and releases all associated resources. |
| OH_ResourceManager_GetRawFileOffset (const RawFile *rawFile) | Obtains the current offset of the rawfile in int32_t. |
| OH_ResourceManager_GetRawFileDescriptor (const RawFile *rawFile, RawFileDescriptor &descriptor) | Opens a rawfile descriptor. |
| OH_ResourceManager_ReleaseRawFileDescriptor (const RawFileDescriptor &descriptor) | Closes a rawfile descriptor. |
| OH_ResourceManager_InitNativeResourceManager (napi_env env, napi_value jsResMgr) | Obtains the native resource manager based on JavaScipt resource manager. |
| OH_ResourceManager_ReleaseNativeResourceManager (NativeResourceManager *resMgr) | Releases a native resource manager. |
| OH_ResourceManager_OpenRawDir (const NativeResourceManager *mgr, const char *dirName) | Opens a rawfile directory. |
| OH_ResourceManager_OpenRawFile (const NativeResourceManager *mgr, const char *fileName) | Opens a rawfile. |
Type Description
NativeResourceManager
typedef struct NativeResourceManagerNativeResourceManager
Description
Implements the resource manager.
This class encapsulates the native implementation of the JavaScript resource manager. You can obtain the pointer to ResourceManager by calling OH_ResourceManager_InitNativeResourceManager.
RawDir
typedef struct RawDirRawDir
Description
Provides the function of accessing rawfile directories.
RawFile
typedef struct RawFileRawFile
Description
Provides the function of accessing rawfiles.
Function Description
OH_ResourceManager_CloseRawDir()
void OH_ResourceManager_CloseRawDir (RawDir * rawDir)
Description
Closes an opened RawDir and releases all associated resources.
Parameters
| Name | Description |
|---|---|
| rawDir | Indicates the pointer to RawDir. |
See
OH_ResourceManager_CloseRawFile()
void OH_ResourceManager_CloseRawFile (RawFile * rawFile)
Description
Closes an opened RawFile and releases all associated resources.
Parameters
| Name | Description |
|---|---|
| rawFile | Indicates the pointer to RawFile. |
See
OH_ResourceManager_OpenRawFile
OH_ResourceManager_GetRawFileCount()
int OH_ResourceManager_GetRawFileCount (RawDir * rawDir)
Description
Obtains the number of rawfiles in RawDir.
You can use this function to obtain available indexes in OH_ResourceManager_GetRawFileName.
Parameters
| Name | Description |
|---|---|
| rawDir | Indicates the pointer to RawDir. |
See
OH_ResourceManager_GetRawFileName
OH_ResourceManager_GetRawFileDescriptor()
bool OH_ResourceManager_GetRawFileDescriptor (const RawFile * rawFile, RawFileDescriptor & descriptor )
Description
Opens a rawfile descriptor.
After the descriptor is opened, you can use it to read the rawfile based on the offset (in int32_t) and file length.
Parameters
| Name | Description |
|---|---|
| rawFile | Indicates the pointer to RawFile. |
| descriptor | Indicates the rawfile descriptor, and the start position and length of the rawfile file in the HAP package. |
Returns
Returns true if the rawfile descriptor is opened successfully; returns false if the rawfile cannot be accessed.
OH_ResourceManager_GetRawFileName()
const char* OH_ResourceManager_GetRawFileName (RawDir * rawDir, int index )
Description
Obtains the rawfile name via an index.
You can use this function to traverse a rawfile directory.
Parameters
| Name | Description |
|---|---|
| rawDir | Indicates the pointer to RawDir. |
| index | Indicates the index of the file in RawDir. |
Returns
Returns the rawfile name via an index. The return value can be used as the input parameter of OH_ResourceManager_OpenRawFile. If no rawfile is found after all rawfiles are traversed, NULL will be returned.
See
OH_ResourceManager_OpenRawFile
OH_ResourceManager_GetRawFileOffset()
long OH_ResourceManager_GetRawFileOffset (const RawFile * rawFile)
Description
Obtains the current offset of the rawfile in int32_t.
Parameters
| Name | Description |
|---|---|
| rawFile | Indicates the pointer to RawFile. |
Returns
Returns the current offset of the rawfile.
OH_ResourceManager_GetRawFileSize()
long OH_ResourceManager_GetRawFileSize (RawFile * rawFile)
Description
Obtains the length of a rawfile in int32_t.
Parameters
| Name | Description |
|---|---|
| rawFile | Indicates the pointer to RawFile. |
Returns
Returns the total length of the rawfile.
OH_ResourceManager_InitNativeResourceManager()
NativeResourceManager* OH_ResourceManager_InitNativeResourceManager (napi_env env, napi_value jsResMgr )
Description
Obtains the native resource manager based on JavaScipt resource manager.
After obtaining a resource manager, you can use it complete various rawfile operations.
Parameters
| Name | Description |
|---|---|
| env | Indicates the pointer to the JavaScipt Native Interface (napi) environment. |
| jsResMgr | Indicates the JavaScipt resource manager. |
Returns
Returns the pointer to NativeResourceManager.
OH_ResourceManager_OpenRawDir()
RawDir* OH_ResourceManager_OpenRawDir (const NativeResourceManager * mgr, const char * dirName )
Description
Opens a rawfile directory.
After opening a rawfile directory, you can traverse all the rawfile files in it.
Parameters
| Name | Description |
|---|---|
| mgr | Indicates the pointer to NativeResourceManager. You can obtain this pointer by calling OH_ResourceManager_InitNativeResourceManager. |
| dirName | Indicates the name of the rawfile directory to open. If this field is left empty, the root directory of rawfile will be opened. |
Returns
Returns the pointer to RawDir. If this pointer is no longer needed after use, call OH_ResourceManager_CloseRawDir to release it.
See
OH_ResourceManager_InitNativeResourceManager
OH_ResourceManager_CloseRawDir
OH_ResourceManager_OpenRawFile()
RawFile* OH_ResourceManager_OpenRawFile (const NativeResourceManager * mgr, const char * fileName )
Description
Opens a rawfile.
After a rawfile is opened, you can read the data in it.
Parameters
| Name | Description |
|---|---|
| mgr | Indicates the pointer to NativeResourceManager. You can obtain this pointer by calling OH_ResourceManager_InitNativeResourceManager. |
| fileName | Indicates the file name in the relative path of the rawfile root directory. |
Returns
Returns the pointer to RawFile. If this pointer is no longer needed after use, call OH_ResourceManager_CloseRawFile to release it.
See
OH_ResourceManager_InitNativeResourceManager
OH_ResourceManager_CloseRawFile
OH_ResourceManager_ReadRawFile()
int OH_ResourceManager_ReadRawFile (const RawFile * rawFile, void * buf, size_t length )
Description
Reads a rawfile.
You can use this function to read data of the specified length from the current position.
Parameters
| Name | Description |
|---|---|
| rawFile | Indicates the pointer to RawFile. |
| buf | Indicates the pointer to the buffer for storing the read data. |
| length | Indicates the length of the read data, in bytes. |
Returns
Returns the length of the read data in bytes. If the length is beyond the end of the rawfile, 0 will be returned.
OH_ResourceManager_ReleaseNativeResourceManager()
void OH_ResourceManager_ReleaseNativeResourceManager (NativeResourceManager * resMgr)
Description
Releases a native resource manager.
Parameters
| Name | Description |
|---|---|
| resMgr | Indicates the pointer to NativeResourceManager. |
OH_ResourceManager_ReleaseRawFileDescriptor()
bool OH_ResourceManager_ReleaseRawFileDescriptor (const RawFileDescriptor & descriptor)
Description
Closes a rawfile descriptor.
To prevent file descriptor leakage, you are advised to release a rawfile descriptor after use.
Parameters
| Name | Description |
|---|---|
| descriptor | Indicates the rawfile descriptor, and the start position and length of the rawfile file in the HAP package. |
Returns
Returns true if the rawfile descriptor is closed successfully; returns false otherwise.
OH_ResourceManager_SeekRawFile()
int OH_ResourceManager_SeekRawFile (const RawFile * rawFile, long offset, int whence )
Description
Seeks for the data read/write position in the rawfile based on the specified offset.
Parameters
| Name | Description |
|---|---|
| rawFile | Indicates the pointer to RawFile. |
| offset | Indicates the specified offset. |
| whence | Indicates the data read/write position. The options are as follows: 0: The read/write position is offset. 1: The read/write position is the current position plus offset. 2: The read/write position is the end of the file (EOF) plus offset. |
Returns
Returns the new data read/write position if the operation is successful; returns (long) -1 otherwise.