Index: src/OFZIPArchive.m
==================================================================
--- src/OFZIPArchive.m
+++ src/OFZIPArchive.m
@@ -83,45 +83,10 @@
 - initWithArchiveFile: (OFString*)path
 	       offset: (off_t)offset
       localFileHeader: (OFZIPArchive_LocalFileHeader*)localFileHeader;
 @end
 
-void
-of_zip_archive_find_extra_field(OFDataArray *extraField, uint16_t tag,
-    uint8_t **data, uint16_t *size)
-{
-	uint8_t *bytes;
-	size_t i, count;
-
-	bytes = [extraField items];
-	count = [extraField count];
-
-	for (i = 0; i < count;) {
-		uint16_t currentTag, currentSize;
-
-		if (i + 3 >= count)
-			@throw [OFInvalidFormatException exception];
-
-		currentTag = (bytes[i + 1] << 8) | bytes[i];
-		currentSize = (bytes[i + 3] << 8) | bytes[i + 2];
-
-		if (i + 3 + currentSize >= count)
-			@throw [OFInvalidFormatException exception];
-
-		if (currentTag == tag) {
-			*data = bytes + i + 4;
-			*size = currentSize;
-			return;
-		}
-
-		i += 4 + currentSize;
-	}
-
-	*data = NULL;
-	*size = 0;
-}
-
 uint32_t
 of_zip_archive_read_field32(uint8_t **data, uint16_t *size)
 {
 	uint32_t field = 0;
 	uint_fast8_t i;
@@ -428,11 +393,11 @@
 		_fileName = [[file readStringWithLength: fileNameLength
 					       encoding: encoding] copy];
 		_extraField = [[file
 		    readDataArrayWithCount: extraFieldLength] retain];
 
-		of_zip_archive_find_extra_field(_extraField, 0x0001,
+		of_zip_archive_entry_find_extra_field(_extraField, 0x0001,
 		    &ZIP64, &ZIP64Size);
 
 		if (ZIP64 != NULL) {
 			if (_uncompressedSize == 0xFFFFFFFF)
 				_uncompressedSize = of_zip_archive_read_field64(

Index: src/OFZIPArchiveEntry.h
==================================================================
--- src/OFZIPArchiveEntry.h
+++ src/OFZIPArchiveEntry.h
@@ -14,11 +14,11 @@
  * file.
  */
 
 #import "OFObject.h"
 
-#include <stdio.h>
+/*! @file */
 
 @class OFString;
 @class OFDataArray;
 @class OFFile;
 @class OFDate;
@@ -100,5 +100,22 @@
  *
  * @return The extra field of the entry
  */
 - (OFDataArray*)extraField;
 @end
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*!
+ * @brief Gets a pointer to and the size of the extra field with the specified
+ *	  tag.
+ *
+ * @param data A pointer to a pointer that should be set to the start of the
+ *	       extra field with the specified tag
+ * @param size A pointer to an uint16_t that should be set to the size
+ */
+extern void of_zip_archive_entry_find_extra_field(OFDataArray *extraField,
+    uint16_t tag, uint8_t **data, uint16_t *size);
+#ifdef __cplusplus
+}
+#endif

Index: src/OFZIPArchiveEntry.m
==================================================================
--- src/OFZIPArchiveEntry.m
+++ src/OFZIPArchiveEntry.m
@@ -27,14 +27,47 @@
 #import "macros.h"
 
 #import "OFInvalidArgumentException.h"
 #import "OFInvalidFormatException.h"
 
-extern void of_zip_archive_find_extra_field(OFDataArray*, uint16_t, uint8_t**,
-    uint16_t*);
 extern uint32_t of_zip_archive_read_field32(uint8_t**, uint16_t*);
 extern uint64_t of_zip_archive_read_field64(uint8_t**, uint16_t*);
+
+void
+of_zip_archive_entry_find_extra_field(OFDataArray *extraField, uint16_t tag,
+    uint8_t **data, uint16_t *size)
+{
+	uint8_t *bytes;
+	size_t i, count;
+
+	bytes = [extraField items];
+	count = [extraField count];
+
+	for (i = 0; i < count;) {
+		uint16_t currentTag, currentSize;
+
+		if (i + 3 >= count)
+			@throw [OFInvalidFormatException exception];
+
+		currentTag = (bytes[i + 1] << 8) | bytes[i];
+		currentSize = (bytes[i + 3] << 8) | bytes[i + 2];
+
+		if (i + 3 + currentSize >= count)
+			@throw [OFInvalidFormatException exception];
+
+		if (currentTag == tag) {
+			*data = bytes + i + 4;
+			*size = currentSize;
+			return;
+		}
+
+		i += 4 + currentSize;
+	}
+
+	*data = NULL;
+	*size = 0;
+}
 
 @implementation OFZIPArchiveEntry
 - (instancetype)OF_initWithFile: (OFFile*)file
 {
 	self = [super init];
@@ -75,11 +108,11 @@
 		_extraField = [[file
 		    readDataArrayWithCount: extraFieldLength] retain];
 		_fileComment = [[file readStringWithLength: fileCommentLength
 						  encoding: encoding] copy];
 
-		of_zip_archive_find_extra_field(_extraField, 0x0001,
+		of_zip_archive_entry_find_extra_field(_extraField, 0x0001,
 		    &ZIP64, &ZIP64Size);
 
 		if (ZIP64 != NULL) {
 			if (_uncompressedSize == 0xFFFFFFFF)
 				_uncompressedSize = of_zip_archive_read_field64(