I'm working on iOS and I want to read rtf data thats in an NSData (actually its an attribute in a core data entity). I'm using the following code:
NSString *temp = [NSString stringWithUTF8String:[self.task.notes bytes]];
NSLog(#"%# %i", temp, [temp length]);
The console yields the message "rtfd 4". But I'm looking for the rtfd raw data.
Thank you for your help,
Jose.
this may or not be of any help
// USAGE NSLog(#"%#",[Utilities dataToString:data delimiter:#"|"]);
+(NSString*)dataToString:(NSData*)inData delimiter:(NSString*)delimiter {
if ([inData length] == 0) {
return #"";
}
if (delimiter == nil) {
delimiter = #"";
}
const unsigned char * p= (const unsigned char *) [inData bytes];
NSMutableString* outString= [[NSMutableString alloc]initWithCapacity:[inData length]*3];
for (int i=0; i< [inData length]; i++) {
[outString appendFormat:#"%02x",p[i]];
[outString appendString:delimiter];
}
[outString autorelease];
return outString;
}
If you want the raw string of a RTFD data stream, then you use this code in Swift:
let raw = String(data: data, encoding: .ascii)
In case you have a RTF data stream, use this code:
let raw = String(data: data, encoding: .utf8)
Related
I have to use Blowfish algorithm in my code for encryption and decryption. After calling the decryption method, blowfishDecrypt, I am getting the value in NSData but it give me always null when I convert it to NSString.
I am using the following code :
-(void)methodCalled
{
syncTime=#"c7c937169084b20c3ff882dcda193a59";
NSData* data = [syncTime dataUsingEncoding:NSUTF8StringEncoding];
NSData* data2 = [#"R=U!LH$O2B#" dataUsingEncoding:NSUTF8StringEncoding];
NSData* dycryptData=[self blowfishDecrypt:data usingKey:data2];
// prints <0eec37b6 2b76c2df cdf72356 0f033ed8 d6bd37dd 5223bf66 5c318ebe 07f3cf71>
NSLog(#"%#",dycryptData);
NSString *dSync=[[NSString alloc] initWithBytes:[dycryptData bytes]
length:[dycryptData length]
encoding:NSUTF8StringEncoding];
// prints (null)
NSLog(#"Sync timeis %#",dSync);
}
-(NSData *)blowfishDecrypt:(NSData *)messageData
usingKey:(NSData *)secretKeyData {
NSMutableData *decryptedData = [messageData mutableCopy];
BLOWFISH_CTX ctx;
Blowfish_Init (&ctx, (unsigned char*)[secretKeyData bytes], [secretKeyData length]);
NSRange aLeftRange, aRightRange;
NSData *aLeftBox, *aRightBox;
unsigned long dl = 0, dr = 0;
for (int i = 0; i< [decryptedData length]; i += 8) { // Divide data into octets...
// …and then into quartets
aLeftRange = NSMakeRange(i, 4);
aRightRange = NSMakeRange(i + 4, 4);
aLeftBox = [decryptedData subdataWithRange:aLeftRange];
aRightBox = [decryptedData subdataWithRange:aRightRange];
// Convert bytes into unsigned long
[aLeftBox getBytes:&dl length:sizeof(unsigned long)];
[aRightBox getBytes:&dr length:sizeof(unsigned long)];
// Decipher
Blowfish_Decrypt(&ctx, &dl, &dr);
// Put bytes back
[decryptedData replaceBytesInRange:aLeftRange withBytes:&dl];
[decryptedData replaceBytesInRange:aRightRange withBytes:&dr];
}
return decryptedData;
}
Blowfish library code can be found eg. here
HINT#1 //general answer
NSString provides an initializer for this purpose. You can see more info using the docs here.
NSString * dSync = [[NSString alloc] initWithData: dycryptData
encoding:NSUTF8StringEncoding];
Assuming you use ARC.
HINT#2 // the answer for this particular question
I tried your code and confirm the above NSString conversion returns null. So why it is not working? dycryptData is stream of bytes represented as hex, so I tried the following and received the desired result:
int dycryptData_len = [dycryptData length];
NSMutableString *dSync_hex = [NSMutableString stringWithCapacity:dycryptData_len*2];
const unsigned char *dycryptData_bytes = [dycryptData bytes];
for (int i = 0; i < dycryptData_len; ++i) {
[dSync_hex appendFormat:#"%02x", dycryptData_bytes[i]];
}
NSLog(#"dSync_hex=%#",dSync_hex);
I can see this result in log output:
dSync_hex=0eec37b62b76c2dfcdf723560f033ed8d6bd37dd5223bf665c318ebe07f3cf71
Can anyone suggest a method to read bytes from NSData (like read function in #interface NSInputStream : NSStream)
How to read binary bytes in NSData? may help you:
NSString *path = #"…put the path to your file here…";
NSData * fileData = [NSData dataWithContentsOfFile: path];
const char* fileBytes = (const char*)[fileData bytes];
NSUInteger length = [fileData length];
NSUInteger index;
for (index = 0; index<length; index++) {
char aByte = fileBytes[index];
//Do something with each byte
}
You can also create an NSInputStream from an NSData object, if you need the read interface:
NSData *data = ...;
NSInputStream *readData = [[NSInputStream alloc] initWithData:data];
[readData open];
However, you should be aware that initWithData copies the contents of data.
One of the simplest ways is to use NSData getBytes:range:.
NSData *data = ...;
char buffer[numberOfBytes];
[data getBytes:buffer range:NSMakeRange(position, numberOfBytes)];
where position and length is the position you want to read from in NSData and the length is how many bytes you want to read. No need to copy.
Alex already mentioned NSData getBytes:range: but there is also NSData getBytes:length: which starts from the first byte.
NSData *data = ...;
char buffer[numberOfBytes];
[data getBytes:buffer length:numberOfBytes];
May way of doing that..
do not forget to free byte array after usage.
NSData* dat = //your code
NSLog(#"Receive from Peripheral: %#",dat);
NSUInteger len = [dat length];
Byte *bytedata = (Byte*)malloc(len);
[dat getBytes:bytedata length:len];
int p = 0;
while(p < len)
{
printf("%02x",bytedata[p]);
if(p!=len-1)
{
printf("-");
}//printf("%c",bytedata[p]);
p++;
}
printf("\n");
// byte array manipulation
free(bytedata);
I want to send a struct to another player in GameCenter.
I have read the other questions about this, however, I cannot get any of them to work.
I need to get #"1234" into a char[4] (ex char[0] = '1', char[1] = '2', etc)
I have tried [NSString UTF8String], but it doesn't seem to do what I want.
It assigns fine, but when I pull it back into NSString * with [NSString stringWithUTF8String:], It returns blank.
If someone could show me the conversion to and from, it would be greatly appreciated.
Thanks.
EDIT:
I can't get it to work :/ Here is my code (the abridged version):
Matchmaker.h
enum { NChars = 4 };
typedef struct {
MessageType messageType;
} Message;
typedef struct {
Message message;
char code[NChars];
} MessageGameCode;
#interface Matchmaker : CCLayer <GameCenterMasterDelegate>{
NSString *_code;
}
#property (nonatomic,retain) NSString *_code;
Matchmaker.m
#synthesize _code;
-(void)viewDidLoad{
self._code = #"1234";
}
- (void)sendCode {
NSLog(#"Sending Code....");
MessageGameCode message;
message.message.messageType = kMessageTypeGameCode;
NSString * const source = self._code;
const char* const sourceAsUTF8 = source.UTF8String;
for (size_t idx = 0; idx < NChars; ++idx) {
message.code[idx] = sourceAsUTF8[idx];
}
NSData *data = [NSData dataWithBytes:&message length:NChars];
[self sendData:data];
}
- (void)match:(GKMatch *)match didReceiveData:(NSData *)data fromPlayer:(NSString *)playerID {
Message *message = (Message *) [data bytes];
if (message->messageType == kMessageTypeGameCode) {
MessageGameCode *codeMessage = (MessageGameCode *)[data bytes];
self._code = [[NSString alloc] initWithBytes:codeMessage->code length:NChars encoding:NSUTF8StringEncoding];
[self setGameState:kGameStateWaitingForStart];
NSLog(#"Game Code Recieved");
NSLog(#"Recieved Code: %#",self._code); //This always shows self._code as blank
}
}
Your attempt will fail because the cstring which you pass to + [NSString stringWithUTF8String:] is not terminated.
Try this:
NSString * result = [[NSString alloc] initWithBytes:bytes
length:4
encoding:NSUTF8StringEncoding];
Edit
A more complete demonstration:
enum { NChars = 4 };
/* requires error checking */
void transmit() {
NSString * const source = #"1234";
char tmp[NChars] = { 0 };
const char* const sourceAsUTF8 = source.UTF8String;
for (size_t idx = 0; idx < NChars; ++idx) {
tmp[idx] = sourceAsUTF8[idx];
}
/* .. */
}
/* requires error checking */
void receive(const char bytes[NChars]) {
NSString * result = [[NSString alloc] initWithBytes:bytes length:NChars encoding:NSUTF8StringEncoding];
/* ... */
}
One way is
char bytes[4];
NSData* data = [#"1234" dataUsingEncoding: NSUTF8StringEncoding];
if ([data length] <= 4)
{
memcpy(bytes, [data bytes], [data length]);
}
And to go the other way:
NSString* recodedString = [[NSString alloc] initWithBytes: bytes
length: savedLengthFromBefore
encoding: NSUTF8StringEncoding];
There are a couple of possible pitfalls here.
One is that with [NSString UTF8String] "The returned C string is automatically freed just as a returned object would be released; you should copy the C string if it needs to store it outside of the autorelease context in which the C string is created.". So, depending on how long you're expecting the value to stick around you may need to copy it (for example, using strcpy)
The other issue is that [NSString UTF8String] and [NSString stringWithUTF8String:] both expect NULL-terminated C strings, so you need a char[5], not a char[4] to hold #"1234".
I'm using the NSData+compression.h and the Base64Transcoder.h elements to be able to zip and unzip content.
Basically to unzip the server responses.
The unzip method works perfectly
+ (NSString *) unzip: (NSString*) stringValue{
Byte inputData[[stringValue lengthOfBytesUsingEncoding:NSUTF8StringEncoding]];
[[stringValue dataUsingEncoding:NSUTF8StringEncoding] getBytes:inputData];
size_t inputDataSize = (size_t)[stringValue length];
size_t outputDataSize = EstimateBas64DecodedDataSize(inputDataSize);
Byte outputData[outputDataSize];//prepare a Byte[] for the decoded data
Base64DecodeData(inputData, inputDataSize, outputData, &outputDataSize);
NSData *theData = [[NSData alloc] initWithBytes:outputData length:outputDataSize];
//And now we gunzip:
NSData* result = [theData gzipInflate];//make bigger==gunzip
NSString *temp = [[NSString alloc] initWithData:result encoding:NSUTF8StringEncoding];
return temp;
}
But when I try to zip a content, using the simetric way, the gzipDeflate fails, and return an empty or nil value.
This is my zip code
+ (NSData *) zip:(NSData *) theSourceData {
// And now we zip:
NSData *result = [theSourceData gzipDeflate];
Byte inputData[[result length]];
[result getBytes:inputData];
size_t inputDataSize = (size_t)[result length];
size_t outputDataSize = EstimateBas64DecodedDataSize(inputDataSize);
char outputData[outputDataSize];//prepare a Byte[] for the decoded data
Base64EncodeData(inputData, inputDataSize, outputData, &outputDataSize, NO);
NSData *theData = [[NSData alloc] initWithBytes:outputData length:outputDataSize];
return theData;
}
Any suggestions?
Thanks
The problem was on the Base64 encoder.
+ (NSString *) zip:(NSData *) theSourceData {
// And now we zip:
NSData *result = [theSourceData gzipDeflate];
NSString *source = [NSString base64StringFromData:result length:[result length]];
return source;
}
We've integrated the base64StringFromData:length: method to solve it.
Thanks,
Ivan
I currently have an NSString containing hex values. I need to convert this NSString object into an NSData object, without changing its contents at all.
I use this code to "parse" the debug output of an NSData object (what you get in the console if you just NSLog an NSData object) back into NSData:
-(NSData*) bytesFromHexString:(NSString *)aString;
{
NSString *theString = [[aString componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] componentsJoinedByString:nil];
NSMutableData* data = [NSMutableData data];
int idx;
for (idx = 0; idx+2 <= theString.length; idx+=2) {
NSRange range = NSMakeRange(idx, 2);
NSString* hexStr = [theString substringWithRange:range];
NSScanner* scanner = [NSScanner scannerWithString:hexStr];
unsigned int intValue;
if ([scanner scanHexInt:&intValue])
[data appendBytes:&intValue length:1];
}
return data;
}
It's not my most robust code, but it does the job of parsing [nsdata_object description].