plbase64.h (2891B)
1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* This Source Code Form is subject to the terms of the Mozilla Public 3 * License, v. 2.0. If a copy of the MPL was not distributed with this 4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 5 6 #ifndef _plbase64_h 7 #define _plbase64_h 8 9 #include "prtypes.h" 10 11 PR_BEGIN_EXTERN_C 12 13 /* 14 * PL_Base64Encode 15 * 16 * This routine encodes the data pointed to by the "src" parameter using the 17 * base64 algorithm, and returns a pointer to the result. If the "srclen" 18 * parameter is not zero, it specifies the length of the source data. If it 19 * is zero, the source data is assumed to be null-terminated, and PL_strlen 20 * is used to determine the source length. If the "dest" parameter is not 21 * null, it is assumed to point to a buffer of sufficient size (which may be 22 * calculated: ((srclen + 2)/3)*4) into which the encoded data is placed 23 * (without any termination). If the "dest" parameter is null, a buffer is 24 * allocated from the heap to hold the encoded data, and the result *will* 25 * be terminated with an extra null character. It is the caller's 26 * responsibility to free the result when it is allocated. A null is returned 27 * if the allocation fails. 28 * 29 * NOTE: when calculating ((srclen + 2)/3)*4), first ensure that 30 * srclen <= (PR_UINT32_MAX/4) * 3 31 * to avoid PRUint32 overflow. 32 */ 33 34 PR_EXTERN(char *) 35 PL_Base64Encode 36 ( 37 const char *src, 38 PRUint32 srclen, 39 char *dest 40 ); 41 42 /* 43 * PL_Base64Decode 44 * 45 * This routine decodes the data pointed to by the "src" parameter using 46 * the base64 algorithm, and returns a pointer to the result. The source 47 * may either include or exclude any trailing '=' characters. If the 48 * "srclen" parameter is not zero, it specifies the length of the source 49 * data. If it is zero, PL_strlen will be used to determine the source 50 * length. If the "dest" parameter is not null, it is assumed to point to 51 * a buffer of sufficient size (which may be calculated: (srclen * 3)/4 52 * when srclen includes the '=' characters) into which the decoded data 53 * is placed (without any termination). If the "dest" parameter is null, 54 * a buffer is allocated from the heap to hold the decoded data, and the 55 * result *will* be terminated with an extra null character. It is the 56 * caller's responsibility to free the result when it is allocated. A null 57 * is retuned if the allocation fails, or if the source is not well-coded. 58 * 59 * NOTE: when calculating (srclen * 3)/4, first ensure that 60 * srclen <= PR_UINT32_MAX/3 61 * to avoid PRUint32 overflow. Alternatively, calculate 62 * (srclen/4) * 3 + ((srclen%4) * 3)/4 63 * which is equivalent but doesn't overflow for any value of srclen. 64 */ 65 66 PR_EXTERN(char *) 67 PL_Base64Decode 68 ( 69 const char *src, 70 PRUint32 srclen, 71 char *dest 72 ); 73 74 PR_END_EXTERN_C 75 76 #endif /* _plbase64_h */