I use following technique to manage my logs. I print logs to asl_log and before, regards to flag [DebugManager shared] isDebugging I want to send log line to other class (method addLogEvent)
#if !defined(TheLog)
#define TheLog(fmt, ...) { \
if ([[DebugManager shared] isDebugging]) \
addLogEvent(__PRETTY_FUNCTION__,fmt,##__VA_ARGS__); \
}
#endif
#define __AF_MAKE_LOG_FUNCTION(LEVEL, NAME) \
inline void NAME(NSString *format, ...)\
{ \
TheLog(__PRETTY_FUNCTION__,format,##__VA_ARGS__);\
va_list arg_list; \
va_start(arg_list, format); \
NSString *formattedString = [[NSString alloc] initWithFormat:format arguments:arg_list]; \
asl_add_log_file(NULL, STDERR_FILENO); \
asl_log(NULL, NULL, (LEVEL), "PREFIX: %s", [formattedString UTF8String]); \
va_end(arg_list); \
}
// Something has failed.
__AF_MAKE_LOG_FUNCTION(ASL_LEVEL_ERR, AFLogError)
// Something is amiss and might fail if not corrected.
__AF_MAKE_LOG_FUNCTION(ASL_LEVEL_WARNING, AFLogWarning)
// The lowest priority for user log
__AF_MAKE_LOG_FUNCTION(ASL_LEVEL_INFO, AFLogDebug)
I map log level with __AF_MAKE_LOG_FUNCTION(LEVEL, NAME) and I need to call TheLog(__PRETTY_FUNCTION__,format,##__VA_ARGS__);\ from inline void NAME(NSString *format, ...)
I get an error:
Pasting formed ',__VA_ARGS__', an invalid preprocessing token
How can I fetch ,__VA_ARGS__ and __PRETTY_FUNCTION__?
This line:
TheLog(__PRETTY_FUNCTION__,format,##__VA_ARGS__);\
is part of the definition of this macro:
#define __AF_MAKE_LOG_FUNCTION(LEVEL, NAME) \
Note that that macro does not take a variable argument list. Therefore, there's no __VA_ARGS__ defined within its definition.
The fact that the function being defined by an instantiation of __AF_MAKE_LOG_FUNCTION — the inline void NAME() — takes a variable argument list isn't relevant. If that function wants to pass the variable argument list along to another function, it needs to do it using the stdarg functionality, as it does for -[NSString initWithFormat:arguments:], but that doesn't work for your TheLog macro, because it's not designed to accept a va_list.
You can't do what you're attempting. Your TheLog macro is incompatible with how you're trying to use it. You would need to design an alternative version, such as:
#define TheLogv(fmt, args) { \
if ([[DebugManager shared] isDebugging]) \
addLogEventv(__PRETTY_FUNCTION__,fmt,args); \
}
Note that this would, in turn, require the existence of a function addLogEventv() which accepts a va_list instead of an actual variable argument list. Within the body of the function being defined by __AF_MAKE_LOG_FUNCTION, you'd have to start and end the list twice, once around each time you pass it to another function, because each function will "consume" it:
#define __AF_MAKE_LOG_FUNCTION(LEVEL, NAME) \
inline void NAME(NSString *format, ...)\
{ \
va_list arg_list; \
va_start(arg_list, format); \
TheLogv(__PRETTY_FUNCTION__,format,arg_list);\
va_end(arg_list); \
va_start(arg_list, format); \
NSString *formattedString = [[NSString alloc] initWithFormat:format arguments:arg_list]; \
asl_add_log_file(NULL, STDERR_FILENO); \
asl_log(NULL, NULL, (LEVEL), "PREFIX: %s", [formattedString UTF8String]); \
va_end(arg_list); \
}
You could also change your TheLog() macro to take an NSString* and simply pass in the formattedString that's already being created.
I want to write a macro to generate 2 methods like below:
- (NSString*)propertyName
{
NSString *key = #"PropertyName";
//get value from NSUserDefaults
//...
}
- (void)setPropertyName:(NSString*)value
{
NSString *key = #"PropertyName";
//set value to NSUserDefaults
//...
}
The first letter of property name is lower case in the get method, upper case in the set method and key value.
The macro should receive 1 or 2 arguments which is the property name:
MY_PROPERTY(propertyName)
or
MY_PROPERTY(PropertyName)
or
MY_PROPERTY(propertyName, PropertyName)
The argument is also the value for key (string value).
How to write a macro for this? I prefer the first or second one. Thanks.
Let's get mad:
#define STRINGIFY(__TEXT__) [NSString stringWithFormat:#"%s", (#__TEXT__)]
#define GENERATE_GETTER_AND_SETTER(__UPPER_CASE__, __LOWER_CASE__, __TYPE__) \
- (void)set##__UPPER_CASE__:(__TYPE__)__LOWER_CASE__ { \
NSString *propertyName = STRINGIFY(__UPPER_CASE__); \
\
...
} \
\
- (__TYPE__)__LOWER_CASE__ { \
NSString *propertyName = STRINGIFY(__UPPER_CASE__); \
\
...
return ... \
} \
Usage:
GENERATE_GETTER_AND_SETTER(MyProperty, myProperty, NSArray*)
Note that you have to specify both lower case and upper case names and you have to know the type of the property.
It might be easier to declare the properties as #dynamic and then implement the methods dynamically, see Objective-C forwardInvocation: for more details.
Is there any function that does what NSLog does but without the new line at the end?
see this http://borkware.com/quickies/one?topic=NSString
excerpted from that page:
void LogIt (NSString *format, ...)
{
va_list args;
va_start (args, format);
NSString *string;
string = [[NSString alloc] initWithFormat: format arguments: args];
va_end (args);
printf ("%s\n", [string UTF8String]);
[string release];
} // LogIt
just customize the printf to suit your needs
You can use printf(), but the time won't be displayed, and you won't be able to use the "%#" sequence for objects.
That said, you can implement your own logging function, using printf(), and adding support for objects. You will need to know how to deal with C variable arguments.
you can use some trick. use special unicode character like:u00a0
NSLog(#"\n\n\n\u00a0")
I can't get my head around the syntax for multiple arguments in Objective-C. I have seen this question, but the answer hasn't helped me (yet).
Here is my code (actually I will want to eventually pass to NSString stringWithFormat, but getting an NSLog to work would be good enough for now):
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
// Insert code here to initialize your application
[self log:#"blah blah %d", 32];
}
- (void)log:(NSString *)text, ... {
va_list args;
va_start(args, text);
NSLog(text, args);
}
The argument (or some argument) comes through, but it's got some weird value (output is blah blah 1606412704). How should I pass the values that come in via ...?
There's a variant of NSLog that accepts a va_list called NSLogv:
- (void) log:(NSString *)text, ... {
va_list args;
va_start(args, text);
NSLogv(text, args);
va_end(args);
}
The only way to forward the actual ... (not the va_list) is to use a macro. For example:
#define MyLog(f, ...) { \
NSLog(f, ##__VA_ARGS__); \
[someObject doSomething:f, ##__VA_ARGS__]; \
}
However, this should be used very sparingly, since macros can make code really obfuscated.
You could use -[NSString initWithFormat:arguments:]:
- (void)log:(NSString *)text, ...
{
va_list args;
va_start(args, text);
NSString *log_msg = [[[NSString alloc] initWithFormat:text arguments:args] autorelease];
NSLog(#"%#", log_msg);
}
What is the best way to tokenize/split a NSString in Objective-C?
Found answer here:
NSString *string = #"oop:ack:bork:greeble:ponies";
NSArray *chunks = [string componentsSeparatedByString: #":"];
Everyone has mentioned componentsSeparatedByString: but you can also use CFStringTokenizer (remember that an NSString and CFString are interchangeable) which will tokenize natural languages too (like Chinese/Japanese which don't split words on spaces).
If you just want to split a string, use -[NSString componentsSeparatedByString:]. For more complex tokenization, use the NSScanner class.
If your tokenization needs are more complex, check out my open source Cocoa String tokenizing/parsing toolkit: ParseKit:
http://parsekit.com
For simple splitting of strings using a delimiter char (like ':'), ParseKit would definitely be overkill. But again, for complex tokenization needs, ParseKit is extremely powerful/flexible.
Also see the ParseKit Tokenization documentation.
If you want to tokenize on multiple characters, you can use NSString's componentsSeparatedByCharactersInSet. NSCharacterSet has some handy pre-made sets like the whitespaceCharacterSet and the illegalCharacterSet. And it has initializers for Unicode ranges.
You can also combine character sets and use them to tokenize, like this:
// Tokenize sSourceEntityName on both whitespace and punctuation.
NSMutableCharacterSet *mcharsetWhitePunc = [[NSCharacterSet whitespaceAndNewlineCharacterSet] mutableCopy];
[mcharsetWhitePunc formUnionWithCharacterSet:[NSCharacterSet punctuationCharacterSet]];
NSArray *sarrTokenizedName = [self.sSourceEntityName componentsSeparatedByCharactersInSet:mcharsetWhitePunc];
[mcharsetWhitePunc release];
Be aware that componentsSeparatedByCharactersInSet will produce blank strings if it encounters more than one member of the charSet in a row, so you might want to test for lengths less than 1.
If you're looking to tokenise a string into search terms while preserving "quoted phrases", here's an NSString category that respects various types of quote pairs: "" '' ‘’ “”
Usage:
NSArray *terms = [#"This is my \"search phrase\" I want to split" searchTerms];
// results in: ["This", "is", "my", "search phrase", "I", "want", "to", "split"]
Code:
#interface NSString (Search)
- (NSArray *)searchTerms;
#end
#implementation NSString (Search)
- (NSArray *)searchTerms {
// Strip whitespace and setup scanner
NSCharacterSet *whitespace = [NSCharacterSet whitespaceAndNewlineCharacterSet];
NSString *searchString = [self stringByTrimmingCharactersInSet:whitespace];
NSScanner *scanner = [NSScanner scannerWithString:searchString];
[scanner setCharactersToBeSkipped:nil]; // we'll handle whitespace ourselves
// A few types of quote pairs to check
NSDictionary *quotePairs = #{#"\"": #"\"",
#"'": #"'",
#"\u2018": #"\u2019",
#"\u201C": #"\u201D"};
// Scan
NSMutableArray *results = [[NSMutableArray alloc] init];
NSString *substring = nil;
while (scanner.scanLocation < searchString.length) {
// Check for quote at beginning of string
unichar unicharacter = [self characterAtIndex:scanner.scanLocation];
NSString *startQuote = [NSString stringWithFormat:#"%C", unicharacter];
NSString *endQuote = [quotePairs objectForKey:startQuote];
if (endQuote != nil) { // if it's a valid start quote we'll have an end quote
// Scan quoted phrase into substring (skipping start & end quotes)
[scanner scanString:startQuote intoString:nil];
[scanner scanUpToString:endQuote intoString:&substring];
[scanner scanString:endQuote intoString:nil];
} else {
// Single word that is non-quoted
[scanner scanUpToCharactersFromSet:whitespace intoString:&substring];
}
// Process and add the substring to results
if (substring) {
substring = [substring stringByTrimmingCharactersInSet:whitespace];
if (substring.length) [results addObject:substring];
}
// Skip to next word
[scanner scanCharactersFromSet:whitespace intoString:nil];
}
// Return non-mutable array
return results.copy;
}
#end
If you are looking for splitting linguistic feature's of a string (Words, paragraphs, characters, sentences and lines), use string enumeration:
NSString * string = #" \n word1! word2,%$?'/word3.word4 ";
[string enumerateSubstringsInRange:NSMakeRange(0, string.length)
options:NSStringEnumerationByWords
usingBlock:
^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
NSLog(#"Substring: '%#'", substring);
}];
// Logs:
// Substring: 'word1'
// Substring: 'word2'
// Substring: 'word3'
// Substring: 'word4'
This api works with other languages where spaces are not always the delimiter (e.g. Japanese). Also using NSStringEnumerationByComposedCharacterSequences is the proper way to enumerate over characters, since many non-western characters are more than one byte long.
I had a case where I had to split the console output after an LDAP query with ldapsearch. First set up and execute the NSTask (I found a good code sample here: Execute a terminal command from a Cocoa app). But then I had to split and parse the output so as to extract only the print-server names out of the Ldap-query-output. Unfortunately it is rather tedious string-manipulation which would be no problem at all if we were to manipulate C-strings/arrays with simple C-array operations. So here is my code using cocoa objects. If you have better suggestions, let me know.
//as the ldap query has to be done when the user selects one of our Active Directory Domains
//(an according comboBox should be populated with print-server names we discover from AD)
//my code is placed in the onSelectDomain event code
//the following variables are declared in the interface .h file as globals
#protected NSArray* aDomains;//domain combo list array
#protected NSMutableArray* aPrinters;//printer combo list array
#protected NSMutableArray* aPrintServers;//print server combo list array
#protected NSString* sLdapQueryCommand;//for LDAP Queries
#protected NSArray* aLdapQueryArgs;
#protected NSTask* tskLdapTask;
#protected NSPipe* pipeLdapTask;
#protected NSFileHandle* fhLdapTask;
#protected NSMutableData* mdLdapTask;
IBOutlet NSComboBox* comboDomain;
IBOutlet NSComboBox* comboPrinter;
IBOutlet NSComboBox* comboPrintServer;
//end of interface globals
//after collecting the print-server names they are displayed in an according drop-down comboBox
//as soon as the user selects one of the print-servers, we should start a new query to find all the
//print-queues on that server and display them in the comboPrinter drop-down list
//to find the shares/print queues of a windows print-server you need samba and the net -S command like this:
// net -S yourPrintServerName.yourBaseDomain.com -U yourLdapUser%yourLdapUserPassWord -W adm rpc share -l
//which dispalays a long list of the shares
- (IBAction)onSelectDomain:(id)sender
{
static int indexOfLastItem = 0; //unfortunately we need to compare this because we are called also if the selection did not change!
if ([comboDomain indexOfSelectedItem] != indexOfLastItem && ([comboDomain indexOfSelectedItem] != 0))
{
indexOfLastItem = [comboDomain indexOfSelectedItem]; //retain this index for next call
//the print-servers-list has to be loaded on a per univeristy or domain basis from a file dynamically or from AN LDAP-QUERY
//initialize an LDAP-Query-Task or console-command like this one with console output
/*
ldapsearch -LLL -s sub -D "cn=yourLdapUser,ou=yourOuWithLdapUserAccount,dc=yourDomain,dc=com" -h "yourLdapServer.com" -p 3268 -w "yourLdapUserPassWord" -b "dc=yourBaseDomainToSearchIn,dc=com" "(&(objectcategory=computer)(cn=ps*))" "dn"
//our print-server names start with ps* and we want the dn as result, wich comes like this:
dn: CN=PSyourPrintServerName,CN=Computers,DC=yourBaseDomainToSearchIn,DC=com
*/
sLdapQueryCommand = [[NSString alloc] initWithString: #"/usr/bin/ldapsearch"];
if ([[comboDomain stringValue] compare: #"firstDomain"] == NSOrderedSame) {
aLdapQueryArgs = [NSArray arrayWithObjects: #"-LLL",#"-s", #"sub",#"-D", #"cn=yourLdapUser,ou=yourOuWithLdapUserAccount,dc=yourDomain,dc=com",#"-h", #"yourLdapServer.com",#"-p",#"3268",#"-w",#"yourLdapUserPassWord",#"-b",#"dc=yourFirstDomainToSearchIn,dc=com",#"(&(objectcategory=computer)(cn=ps*))",#"dn",nil];
}
else {
aLdapQueryArgs = [NSArray arrayWithObjects: #"-LLL",#"-s", #"sub",#"-D", #"cn=yourLdapUser,ou=yourOuWithLdapUserAccount,dc=yourDomain,dc=com",#"-h", #"yourLdapServer.com",#"-p",#"3268",#"-w",#"yourLdapUserPassWord",#"-b",#"dc=yourSecondDomainToSearchIn,dc=com",#"(&(objectcategory=computer)(cn=ps*))",#"dn",nil];
}
//prepare and execute ldap-query task
tskLdapTask = [[NSTask alloc] init];
pipeLdapTask = [[NSPipe alloc] init];//instead of [NSPipe pipe]
[tskLdapTask setStandardOutput: pipeLdapTask];//hope to get the tasks output in this file/pipe
//The magic line that keeps your log where it belongs, has to do with NSLog (see https://stackoverflow.com/questions/412562/execute-a-terminal-command-from-a-cocoa-app and here http://www.cocoadev.com/index.pl?NSTask )
[tskLdapTask setStandardInput:[NSPipe pipe]];
//fhLdapTask = [[NSFileHandle alloc] init];//would be redundand here, next line seems to do the trick also
fhLdapTask = [pipeLdapTask fileHandleForReading];
mdLdapTask = [NSMutableData dataWithCapacity:512];//prepare capturing the pipe buffer which is flushed on read and can overflow, start with 512 Bytes but it is mutable, so grows dynamically later
[tskLdapTask setLaunchPath: sLdapQueryCommand];
[tskLdapTask setArguments: aLdapQueryArgs];
#ifdef bDoDebug
NSLog (#"sLdapQueryCommand: %#\n", sLdapQueryCommand);
NSLog (#"aLdapQueryArgs: %#\n", aLdapQueryArgs );
NSLog (#"tskLdapTask: %#\n", [tskLdapTask arguments]);
#endif
[tskLdapTask launch];
while ([tskLdapTask isRunning]) {
[mdLdapTask appendData: [fhLdapTask readDataToEndOfFile]];
}
[tskLdapTask waitUntilExit];//might be redundant here.
[mdLdapTask appendData: [fhLdapTask readDataToEndOfFile]];//add another read for safety after process/command stops
NSString* sLdapOutput = [[NSString alloc] initWithData: mdLdapTask encoding: NSUTF8StringEncoding];//convert output to something readable, as NSData and NSMutableData are mere byte buffers
#ifdef bDoDebug
NSLog(#"LdapQueryOutput: %#\n", sLdapOutput);
#endif
//Ok now we have the printservers from Active Directory, lets parse the output and show the list to the user in its combo box
//output is formatted as this, one printserver per line
//dn: CN=PSyourPrintServer,OU=Computers,DC=yourBaseDomainToSearchIn,DC=com
//so we have to search for "dn: CN=" to retrieve each printserver's name
//unfortunately splitting this up will give us a first line containing only "" empty string, which we can replace with the word "choose"
//appearing as first entry in the comboBox
aPrintServers = (NSMutableArray*)[sLdapOutput componentsSeparatedByString:#"dn: CN="];//split output into single lines and store it in the NSMutableArray aPrintServers
#ifdef bDoDebug
NSLog(#"aPrintServers: %#\n", aPrintServers);
#endif
if ([[aPrintServers objectAtIndex: 0 ] compare: #"" options: NSLiteralSearch] == NSOrderedSame){
[aPrintServers replaceObjectAtIndex: 0 withObject: slChoose];//replace with localized string "choose"
#ifdef bDoDebug
NSLog(#"aPrintServers: %#\n", aPrintServers);
#endif
}
//Now comes the tedious part to extract only the print-server-names from the single lines
NSRange r;
NSString* sTemp;
for (int i = 1; i < [aPrintServers count]; i++) {//skip first line with "choose". To get rid of the rest of the line, we must isolate/preserve the print server's name to the delimiting comma and remove all the remaining characters
sTemp = [aPrintServers objectAtIndex: i];
sTemp = [sTemp stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];//remove newlines and line feeds
#ifdef bDoDebug
NSLog(#"sTemp: %#\n", sTemp);
#endif
r = [sTemp rangeOfString: #","];//now find first comma to remove the whole rest of the line
//r.length = [sTemp lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
r.length = [sTemp length] - r.location;//calculate number of chars between first comma found and lenght of string
#ifdef bDoDebug
NSLog(#"range: %i, %i\n", r.location, r.length);
#endif
sTemp = [sTemp stringByReplacingCharactersInRange:r withString: #"" ];//remove rest of line
#ifdef bDoDebug
NSLog(#"sTemp after replace: %#\n", sTemp);
#endif
[aPrintServers replaceObjectAtIndex: i withObject: sTemp];//put back string into array for display in comboBox
#ifdef bDoDebug
NSLog(#"aPrintServer: %#\n", [aPrintServers objectAtIndex: i]);
#endif
}
[comboPrintServer removeAllItems];//reset combo box
[comboPrintServer addItemsWithObjectValues:aPrintServers];
[comboPrintServer setNumberOfVisibleItems:aPrintServers.count];
[comboPrintServer selectItemAtIndex:0];
#ifdef bDoDebug
NSLog(#"comboPrintServer reloaded with new values.");
#endif
//release memory we used for LdapTask
[sLdapQueryCommand release];
[aLdapQueryArgs release];
[sLdapOutput release];
[fhLdapTask release];
[pipeLdapTask release];
// [tskLdapTask release];//strangely can not be explicitely released, might be autorelease anyway
// [mdLdapTask release];//strangely can not be explicitely released, might be autorelease anyway
[sTemp release];
}
}
I have my self come across instance where it was not enough to just separate string by component many tasks such as 1) Categorizing token into types 2) Adding new tokens 3)Separating string between custom closures like all words between "{" and "}"For any such requirements i found Parse Kit a life saver.
I used it to parse .PGN (prtable gaming notation) files successfully its very fast and lite.