base64EncodedDataWithOptions, base64EncodedStringWithOptions: first implementation

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@38634 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,9 @@
+2015-06-14 Riccardo Mottola <rm@gnu.org>
+
+	* Headers/Foundation/NSData.h
+	* Source/NSData.m
+	base64EncodedDataWithOptions, base64EncodedStringWithOptions: first implementation
+
 2015-06-08  Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Source/NSData.m: be strict about '=' padding only occurring at end

Headers/Foundation/NSData.h

@@ -121,6 +121,12 @@ enum {
 	    range: (NSRange)aRange;
 - (NSData*) subdataWithRange: (NSRange)aRange;
 
+// base64
+#if OS_API_VERSION(MAC_OS_X_VERSION_10_9,GS_API_LATEST) 
+- (NSData *)base64EncodedDataWithOptions:(NSDataBase64EncodingOptions)options;
+- (NSString *)base64EncodedStringWithOptions:(NSDataBase64EncodingOptions)options;
+#endif
+ 
 // Querying a Data Object
 
 - (BOOL) isEqualToData: (NSData*)other;

Source/NSData.m

@@ -1,5 +1,5 @@
 /**
-   Copyright (C) 1995, 1996, 1997, 2000, 2002 Free Software Foundation, Inc.
+   Copyright (C) 1995-2015 Free Software Foundation, Inc.
 
    Written by:  Andrew Kachites McCallum <mccallum@gnu.ai.mit.edu>
    Date: March 1995
@@ -147,6 +147,88 @@ decodebase64(unsigned char *dst, const unsigned char *src)
   dst[2] = ((src[2] & 0x03) << 6) |  (src[3] & 0x3F);
 }
 
+static char b64[]
+  = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+static NSUInteger
+encodebase64(unsigned char **dstRef, const unsigned char *src, NSUInteger length, NSDataBase64EncodingOptions options)
+{
+  unsigned char *dst;
+  NSUInteger dIndex = 0;
+  NSUInteger dIndexNoNewLines = 0;
+  NSUInteger sIndex;
+  NSUInteger lineLength;
+  NSUInteger destLen;
+
+  lineLength = 0;  
+  if (options & NSDataBase64Encoding64CharacterLineLength)
+    lineLength = 64;
+  else if (options & NSDataBase64Encoding76CharacterLineLength)
+    lineLength = 76;
+
+  /* if no EndLine options are set but a line length is given, CR+LF is implied */
+  if (lineLength && !(options & NSDataBase64EncodingEndLineWithCarriageReturn) && !(options & NSDataBase64EncodingEndLineWithLineFeed))
+    {
+      options |= NSDataBase64EncodingEndLineWithCarriageReturn;
+      options |= NSDataBase64EncodingEndLineWithLineFeed;
+    }
+
+  /* estimate destination length */
+  destLen = 4 * ((length + 2) / 3);
+  /* we need to take in account line-endings */
+  if (lineLength)
+    {
+      if (options & (NSDataBase64EncodingEndLineWithCarriageReturn | NSDataBase64EncodingEndLineWithLineFeed))
+        destLen += (destLen / lineLength)*2;
+      else
+        destLen += (destLen / lineLength);
+    }
+
+#if	GS_WITH_GC
+  dst = NSAllocateCollectable(destLen, 0);
+#else
+  dst = NSZoneMalloc(NSDefaultMallocZone(), destLen);
+#endif
+
+  for (sIndex = 0; sIndex < length; sIndex += 3)
+    {
+      int	c0 = src[sIndex];
+      int	c1 = (sIndex+1 < length) ? src[sIndex+1] : 0;
+      int	c2 = (sIndex+2 < length) ? src[sIndex+2] : 0;
+
+      dst[dIndex++] = b64[(c0 >> 2) & 077];
+      dst[dIndex++] = b64[((c0 << 4) & 060) | ((c1 >> 4) & 017)];
+      dst[dIndex++] = b64[((c1 << 2) & 074) | ((c2 >> 6) & 03)];
+      dst[dIndex++] = b64[c2 & 077];
+      dIndexNoNewLines += 4;
+      if (lineLength && !(dIndexNoNewLines % lineLength) )
+        {
+          if (options & NSDataBase64EncodingEndLineWithCarriageReturn)
+            dst[dIndex++] = '\r';
+          if (options & NSDataBase64EncodingEndLineWithLineFeed)
+            dst[dIndex++] = '\n';
+        }
+    }
+
+   /* If len was not a multiple of 3, then we have encoded too
+    * many characters.  Adjust appropriately.
+    */
+   if (sIndex == length + 1)
+     {
+       /* There were only 2 bytes in that last group */
+       dst[dIndex - 1] = '=';
+     }
+   else if (sIndex == length + 2)
+     {
+       /* There was only 1 byte in that last group */
+       dst[dIndex - 1] = '=';
+       dst[dIndex - 2] = '=';
+     }
+
+  *dstRef = dst;
+  return dIndex;
+}
+
 static BOOL
 readContentsOfFile(NSString* path, void** buf, off_t* len, NSZone* zone)
 {
@@ -221,7 +303,7 @@ readContentsOfFile(NSString* path, void** buf, off_t* len, NSZone* zone)
   if (fileLength == 0)
     {
       unsigned char	buf[BUFSIZ];
-      
+     
       /*
        * Special case ... a file of length zero may be a named pipe or some
        * file in the /proc filesystem, which will return us data if we read
@@ -959,6 +1041,29 @@ failure:
   return [NSData dataWithBytesNoCopy: buffer length: aRange.length];
 }
 
+- (NSData *)base64EncodedDataWithOptions:(NSDataBase64EncodingOptions)options
+{
+  void *srcBytes = (void*)[self bytes];
+  NSUInteger length = [self length];
+  NSUInteger resLen;
+  unsigned char *resBytes;
+
+  resLen = encodebase64(&resBytes, srcBytes, length, options);
+  return AUTORELEASE([[NSData alloc] initWithBytesNoCopy: resBytes length: resLen freeWhenDone: YES]);
+}
+
+- (NSString *)base64EncodedStringWithOptions:(NSDataBase64EncodingOptions)options
+{
+  void *srcBytes = (void*)[self bytes];
+  NSUInteger length = [self length];
+  NSUInteger resLen;
+  unsigned char *resBytes;
+
+  resLen = encodebase64(&resBytes, srcBytes, length, options);
+  return AUTORELEASE([[NSString alloc] initWithBytesNoCopy: resBytes length: resLen encoding: NSASCIIStringEncoding freeWhenDone: YES]);
+}
+
+
 - (NSUInteger) hash
 {
   unsigned char	buf[64];