asxpath.m

#import <Foundation/Foundation.h>

void printUsage () {
	printf("Usage: asxpath -file [XML file path] -xpath [XPath expression]\n");
}

int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
	// getting the arguments passed on the command line
    NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
	NSString *xmlFilePath = [userDefaults stringForKey:@"file"];
	if ((xmlFilePath == NULL) || ([xmlFilePath isEqualToString:@""] == YES)) {
		printf("Error: XML file path is missing.\n");
		printUsage();
		return 1;
	}
	NSString *xpathExpr = [userDefaults stringForKey:@"xpath"];
	if ((xpathExpr == NULL) || ([xpathExpr isEqualToString:@""] == YES)) {
		printf("Error: XPath expression is missing.\n");
		printUsage();
		return 1;
	}
	NSString *delimiter;
	delimiter = [userDefaults stringForKey:@"delim"];
	if ((delimiter == NULL) || ([delimiter isEqualToString:@""] == YES)) {
		delimiter = @"...";
	}
	// does the passed file path exist?
	NSFileManager *fileManager = [NSFileManager defaultManager];
	BOOL isDir;
	if ([fileManager fileExistsAtPath:xmlFilePath isDirectory:&isDir] == NO) {
		printf("Error: The file does not exist: '%s'\n", [xmlFilePath UTF8String]);
		return 1;
	} else {
		if (isDir == YES) {
			printf("Error: The given path points to a directory: '%s'\n", [xmlFilePath UTF8String]);
			return 1;
		}
	}
    NSURL *fileURL = [NSURL fileURLWithPath:xmlFilePath];
    if (!fileURL) {
        printf("Error: Cannot create an URL from file '%s'.", [xmlFilePath UTF8String]);
        return 1;
    }
	// loading the XML file
	NSError *err=nil;
    NSXMLDocument *xmlDoc = [[NSXMLDocument alloc] initWithContentsOfURL:fileURL options:(NSXMLNodePreserveWhitespace|NSXMLNodePreserveCDATA) error:&err];
    if (xmlDoc == nil) {
		printf("Error: Could not create XML object from file '%s'.\n%s", [xmlFilePath UTF8String], [[err localizedDescription] UTF8String]);
		return 1;
    }
	// executing the XPath expression
	NSArray *matchNodes = [xmlDoc nodesForXPath:xpathExpr error:&err];
	if (matchNodes == NULL) {
		if (err == nil) {
			return 0;
		} else {
			printf("Error: %s.\n", [[err localizedDescription] UTF8String]);
			return 1;
		}
	}
	// no match
	if ([matchNodes count] == 0) {
		return 0;
	}
	// printing the result
	id object;
	int countMatchNodes = [matchNodes count];
	int i;
	for  (i =  0; i < countMatchNodes; i++) {
		object = [matchNodes objectAtIndex:i];
		NSString *xml = [object XMLString];
		NSString *stripXML = [xml stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
		if (i == countMatchNodes - 1) {
			printf("%s\n", [stripXML UTF8String]);
		} else {
			printf("%s\n%s\n", [stripXML UTF8String], [delimiter UTF8String]);
		}
	}
    [pool release];
    return 0;
}