#include <VirtualDir.h>
Data Fields | |
| VDCallback_GetInfo | get_info |
| VDCallback_Open | open |
| VDCallback_Read | read |
| VDCallback_Write | write |
| VDCallback_Seek | seek |
| VDCallback_Close | close |
Detailed Description
The VirtualDirCallbacks structure contains the pointers to file-related callback functions a device application can register to virtualize URLs.
Field Documentation
| VDCallback_Close VirtualDirCallbacks::close |
Called by the web server to close a file opened via the open callback. It should return 0 on success, or a non-zero value on an error.
Referenced by http_RecvPostMessage(), http_SendMessage(), UpnpVirtualDir_set_CloseCallback(), and web_server_init().
| VDCallback_GetInfo VirtualDirCallbacks::get_info |
Called by the web server to query information on a file. The callback should return 0 on success or -1 on an error.
Referenced by UpnpVirtualDir_set_GetInfoCallback(), and web_server_init().
| VDCallback_Open VirtualDirCallbacks::open |
Called by the web server to open a file. The callback should return a valid handle if the file can be opened. Otherwise, it should return NULL to signify an error.
Referenced by http_RecvPostMessage(), http_SendMessage(), UpnpVirtualDir_set_OpenCallback(), and web_server_init().
| VDCallback_Read VirtualDirCallbacks::read |
Called by the web server to perform a sequential read from an open file. The callback should copy buflen bytes from the file into the buffer.
- Returns
- An integer representing one of the following:
0: The file contains no more data (EOF).> 0: A successful read of the number of bytes in the return code.< 0: An error occurred reading the file.
Referenced by http_SendMessage(), UpnpVirtualDir_set_ReadCallback(), and web_server_init().
| VDCallback_Seek VirtualDirCallbacks::seek |
Called by the web server to move the file pointer, or offset, into an open file. The origin parameter determines where to start moving the file pointer. A value of SEEK_CUR moves the file pointer relative to where it is. The offset parameter can be either positive (move forward) or negative (move backward). SEEK_END moves relative to the end of the file. A positive offset extends the file. A negative offset moves backward in the file. Finally, SEEK_SET moves to an absolute position in the file. In this case, offset must be positive. The callback should return 0 on a successful seek or a non-zero value on an error.
Referenced by http_SendMessage(), UpnpVirtualDir_set_SeekCallback(), and web_server_init().
| VDCallback_Write VirtualDirCallbacks::write |
Called by the web server to perform a sequential write to an open file. The callback should write buflen bytes into the file from the buffer. It should return the actual number of bytes written, which might be less than buflen in the case of a write error.
Referenced by http_RecvPostMessage(), UpnpVirtualDir_set_WriteCallback(), and web_server_init().
The documentation for this struct was generated from the following file:
- upnp/src/inc/VirtualDir.h
