add .gitignore

msext/Class/webCache/NSString+Sha1.m

@@ -0,0 +1,24 @@
+
+#import "NSString+Sha1.h"
+
+@implementation NSString (Sha1)
+
+- (NSString *)sha1
+{
+    // see http://www.makebetterthings.com/iphone/how-to-get-md5-and-sha1-in-objective-c-ios-sdk/
+    NSData *data = [self dataUsingEncoding:NSUTF8StringEncoding];
+    uint8_t digest[CC_SHA1_DIGEST_LENGTH];
+    
+    CC_SHA1(data.bytes, (CC_LONG)data.length, digest);
+    
+    NSMutableString *output = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];
+    
+    for (int i = 0; i < CC_SHA1_DIGEST_LENGTH; i++) {
+        [output appendFormat:@"%02x", digest[i]];
+    }
+    
+    return output;
+}
+
+
+@end