X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fbase64.c;h=4dbd80a1c0c1797dc0faae125d9fa0b6e5111302;hb=fdba88ca5c48680a219e742f0b3d480daf74703d;hp=97b6019b9d3bb5efbd2646fa0f670e59ef638a61;hpb=112ca20edbdbbede4ffeac64892bb4fc5e1b04d6;p=gnulib.git diff --git a/lib/base64.c b/lib/base64.c index 97b6019b9..4dbd80a1c 100644 --- a/lib/base64.c +++ b/lib/base64.c @@ -1,5 +1,6 @@ /* base64.c -- Encode binary data using printable characters. - Copyright (C) 1999, 2000, 2001, 2004 Free Software Foundation, Inc. + Copyright (C) 1999, 2000, 2001, 2004, 2005, 2006 Free Software + Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -13,7 +14,7 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, - Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /* Written by Simon Josefsson. Partially adapted from GNU MailUtils * (mailbox/filter_trans.c, as of 2004-11-28). Improved by review @@ -36,7 +37,7 @@ * FAIL: input too long * if (out == NULL) * FAIL: memory allocation error - * OK: data in OUT/LEN. + * OK: data in OUT/OUTLEN. * */ @@ -50,6 +51,9 @@ /* Get malloc. */ #include +/* Get UCHAR_MAX. */ +#include + /* C89 compliant way to cast 'char' to 'unsigned char'. */ static inline unsigned char to_uchar (char ch) @@ -65,30 +69,34 @@ void base64_encode (const char *restrict in, size_t inlen, char *restrict out, size_t outlen) { - const char b64[64] = + static const char b64str[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; while (inlen && outlen) { - *out++ = b64[to_uchar (in[0]) >> 2]; + *out++ = b64str[(to_uchar (in[0]) >> 2) & 0x3f]; if (!--outlen) break; - *out++ = b64[((to_uchar (in[0]) << 4) - + (--inlen ? to_uchar (in[1]) >> 4 : 0)) & 0x3f]; + *out++ = b64str[((to_uchar (in[0]) << 4) + + (--inlen ? to_uchar (in[1]) >> 4 : 0)) + & 0x3f]; if (!--outlen) break; *out++ = (inlen - ? b64[((to_uchar (in[1]) << 2) - + (--inlen ? to_uchar (in[2]) >> 6 : 0)) & 0x3f] : '='); + ? b64str[((to_uchar (in[1]) << 2) + + (--inlen ? to_uchar (in[2]) >> 6 : 0)) + & 0x3f] + : '='); if (!--outlen) break; - *out++ = inlen ? b64[to_uchar (in[2]) & 0x3f] : '='; + *out++ = inlen ? b64str[to_uchar (in[2]) & 0x3f] : '='; if (!--outlen) break; if (inlen) inlen--; - in += 3; + if (inlen) + in += 3; } if (outlen) @@ -101,8 +109,8 @@ base64_encode (const char *restrict in, size_t inlen, return, the OUT variable will hold a pointer to newly allocated memory that must be deallocated by the caller. If output string length would overflow, 0 is returned and OUT is set to NULL. If - memory allocation fail, OUT is set to NULL, and the return value - indicate length of the requested memory block, i.e., + memory allocation failed, OUT is set to NULL, and the return value + indicates length of the requested memory block, i.e., BASE64_LENGTH(inlen) + 1. */ size_t base64_encode_alloc (const char *in, size_t inlen, char **out) @@ -128,8 +136,10 @@ base64_encode_alloc (const char *in, size_t inlen, char **out) } *out = malloc (outlen); - if (*out) - base64_encode (in, inlen, *out, outlen); + if (!*out) + return outlen; + + base64_encode (in, inlen, *out, outlen); return outlen - 1; } @@ -274,10 +284,19 @@ static const signed char b64[0x100] = { B64 (252), B64 (253), B64 (254), B64 (255) }; -static inline bool -isb64 (unsigned char ch) +#if UCHAR_MAX == 255 +# define uchar_in_range(c) true +#else +# define uchar_in_range(c) ((c) <= 255) +#endif + +/* Return true if CH is a character from the Base64 alphabet, and + false otherwise. Note that '=' is padding and not considered to be + part of the alphabet. */ +bool +isbase64 (char ch) { - return ch <= 255 && 0 <= b64[ch]; + return uchar_in_range (to_uchar (ch)) && 0 <= b64[to_uchar (ch)]; } /* Decode base64 encoded input array IN of length INLEN to output @@ -286,16 +305,18 @@ isb64 (unsigned char ch) otherwise. If *OUTLEN is too small, as many bytes as possible will be written to OUT. On return, *OUTLEN holds the length of decoded bytes in OUT. Note that as soon as any non-alphabet characters are - encountered, decoding is stopped and false is returned. */ + encountered, decoding is stopped and false is returned. This means + that, when applicable, you must remove any line terminators that is + part of the data stream before calling this function. */ bool base64_decode (const char *restrict in, size_t inlen, - char *restrict out, size_t * outlen) + char *restrict out, size_t *outlen) { size_t outleft = *outlen; while (inlen >= 2) { - if (!isb64 (in[0]) || !isb64 (in[1])) + if (!isbase64 (in[0]) || !isbase64 (in[1])) break; if (outleft) @@ -319,7 +340,7 @@ base64_decode (const char *restrict in, size_t inlen, } else { - if (!isb64 (in[2])) + if (!isbase64 (in[2])) break; if (outleft) @@ -339,7 +360,7 @@ base64_decode (const char *restrict in, size_t inlen, } else { - if (!isb64 (in[3])) + if (!isbase64 (in[3])) break; if (outleft) @@ -368,15 +389,15 @@ base64_decode (const char *restrict in, size_t inlen, size of the decoded data is stored in *OUTLEN. OUTLEN may be NULL, if the caller is not interested in the decoded length. *OUT may be NULL to indicate an out of memory error, in which case *OUTLEN - contain the size of the memory block needed. The function return + contains the size of the memory block needed. The function returns true on successful decoding and memory allocation errors. (Use the *OUT and *OUTLEN parameters to differentiate between successful - decoding and memory error.) The function return false if the input - was invalid, in which case *OUT is NULL and *OUTLEN is + decoding and memory error.) The function returns false if the + input was invalid, in which case *OUT is NULL and *OUTLEN is undefined. */ bool base64_decode_alloc (const char *in, size_t inlen, char **out, - size_t * outlen) + size_t *outlen) { /* This may allocate a few bytes too much, depending on input, but it's not worth the extra CPU time to compute the exact amount.