michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef _plbase64_h
michael@0: #define _plbase64_h
michael@0: 
michael@0: #include "prtypes.h"
michael@0: 
michael@0: PR_BEGIN_EXTERN_C
michael@0: 
michael@0: /*
michael@0:  * PL_Base64Encode
michael@0:  *
michael@0:  * This routine encodes the data pointed to by the "src" parameter using the
michael@0:  * base64 algorithm, and returns a pointer to the result.  If the "srclen"
michael@0:  * parameter is not zero, it specifies the length of the source data.  If it
michael@0:  * is zero, the source data is assumed to be null-terminated, and PL_strlen
michael@0:  * is used to determine the source length.  If the "dest" parameter is not
michael@0:  * null, it is assumed to point to a buffer of sufficient size (which may be
michael@0:  * calculated: ((srclen + 2)/3)*4) into which the encoded data is placed 
michael@0:  * (without any termination).  If the "dest" parameter is null, a buffer is
michael@0:  * allocated from the heap to hold the encoded data, and the result *will*
michael@0:  * be terminated with an extra null character.  It is the caller's 
michael@0:  * responsibility to free the result when it is allocated.  A null is returned 
michael@0:  * if the allocation fails.
michael@0:  *
michael@0:  * NOTE: when calculating ((srclen + 2)/3)*4), first ensure that
michael@0:  *     srclen <= (PR_UINT32_MAX/4) * 3
michael@0:  * to avoid PRUint32 overflow.
michael@0:  */
michael@0: 
michael@0: PR_EXTERN(char *)
michael@0: PL_Base64Encode
michael@0: (
michael@0:     const char *src,
michael@0:     PRUint32    srclen,
michael@0:     char       *dest
michael@0: );
michael@0: 
michael@0: /*
michael@0:  * PL_Base64Decode
michael@0:  *
michael@0:  * This routine decodes the data pointed to by the "src" parameter using
michael@0:  * the base64 algorithm, and returns a pointer to the result.  The source
michael@0:  * may either include or exclude any trailing '=' characters.  If the
michael@0:  * "srclen" parameter is not zero, it specifies the length of the source
michael@0:  * data.  If it is zero, PL_strlen will be used to determine the source
michael@0:  * length.  If the "dest" parameter is not null, it is assumed to point to
michael@0:  * a buffer of sufficient size (which may be calculated: (srclen * 3)/4
michael@0:  * when srclen includes the '=' characters) into which the decoded data
michael@0:  * is placed (without any termination).  If the "dest" parameter is null,
michael@0:  * a buffer is allocated from the heap to hold the decoded data, and the
michael@0:  * result *will* be terminated with an extra null character.  It is the
michael@0:  * caller's responsibility to free the result when it is allocated.  A null
michael@0:  * is retuned if the allocation fails, or if the source is not well-coded.
michael@0:  *
michael@0:  * NOTE: when calculating (srclen * 3)/4, first ensure that 
michael@0:  *     srclen <= PR_UINT32_MAX/3
michael@0:  * to avoid PRUint32 overflow.  Alternatively, calculate
michael@0:  *     (srclen/4) * 3 + ((srclen%4) * 3)/4
michael@0:  * which is equivalent but doesn't overflow for any value of srclen.
michael@0:  */
michael@0: 
michael@0: PR_EXTERN(char *)
michael@0: PL_Base64Decode
michael@0: (
michael@0:     const char *src,
michael@0:     PRUint32    srclen,
michael@0:     char       *dest
michael@0: );
michael@0: 
michael@0: PR_END_EXTERN_C
michael@0: 
michael@0: #endif /* _plbase64_h */