NSInputStream subclass for reading files that are in the secure store. More...
#import <BlackBerryDynamics/GD/GDCReadStream.h>
This class is a subclass of the native NSInputStream
class, for access to the BlackBerry Dynamics secure file system.
This class supports the read
and hasBytesAvailable
member functions of NSInputStream
. This class doesn't support getBuffer
, which will always return NO
. This class also doesn't support scheduleInRunLoop
nor removeFromRunLoop
. Support for run loops isn't required because the file data can be read immediately.
This documentation includes only additional operations provided by GDCReadStream that aren't part of NSInputStream
.
read
function in this class will work best when the supplied buffer is a multiple of 16 bytes in length. The maxLength
parameter should reflect the size of the buffer, and not the amount of data remaining to be read from the file. To read a particular number of bytes, B, supply a buffer whose size is B rounded up to the next multiple of 16.read
function must always be checked by the application. It mustn't be assumed that a file has been completely read into a buffer, even if the buffer is large enough to accomodate the whole file.The functions in this class utilize NSError
in a conventional way. Function calls accept as a parameter the location of a pointer to NSError
, i.e. a pointer to a pointer, with type NSError**
. The location may be nil
. If the location isn't nil
, and an error occurs, the BlackBerry Dynamics runtime overwrites the pointer at the specified location with the address of an object that describes the error that occurred.
Instance Methods | |
(instancetype) | - initWithFile:error: |
Constructor that opens a file in the secure store, for reading. More... | |
(instancetype) | - initWithFile: |
Constructor that opens a file in the secure store, for reading. More... | |
(BOOL) | - seekToFileOffset: |
Seek in an open file in the secure file system. More... | |
(NSError *) | - streamError |
Get the last error. More... | |
- (instancetype) initWithFile: | (NSString *) | filePath | |
error: | (NSError **) | error | |
Call this constructor to open a file in the secure store for reading. Files in the secure store are encrypted on the device; this function provides access to decrypted data.
Note. This constructor is used by the getReadStream: function in the GDFileManager class.
filePath | NSString containing the path, within the secure store, of the file to be opened. |
error | For returning an NSError object if an error occurs. If nil , no object will be returned. |
nil
if the file could not be opened. - (instancetype) initWithFile: | (NSString *) | filePath |
Calling this constructor is equivalent to calling the initWithFile:error: constructor, above, and specifying nil
as the error
parameter.
- (BOOL) seekToFileOffset: | (unsigned long long) | offset |
Call this function to move the file pointer to a specific offset from the start of the stream.
offset | Required offset, expressed as a number of bytes from the start of the file. Zero means the start of the file. |
YES
if the file pointer was moved to the required offset. NO
Otherwise. - (NSError*) streamError |
Call this function to get the last error associated with the open stream.
NSError
object that describes the error.