diff --git a/src/utils/base64.cpp b/src/utils/base64.cpp index ac29569e..dacf99c4 100644 --- a/src/utils/base64.cpp +++ b/src/utils/base64.cpp @@ -23,65 +23,115 @@ using std::string; #endif /* NO_NAMESPACES */ -//#define DEBUG_BASE64 +#undef DEBUG_BASE64 #ifdef DEBUG_BASE64 #define DPRINT(X) fprintf X #else #define DPRINT(X) #endif -// This is adapted from FreeBSD's code. +// This is adapted from FreeBSD's code, quite modified for performance. +// Tests on a Mac pro 2.1G with a 166MB base64 file +// +// The original version used strchr to lookup the base64 value from +// the input code: +// real 0m13.053s user 0m12.574s sys 0m0.471s +// Using a direct access, 256 entries table: +// real 0m3.073s user 0m2.600s sys 0m0.439s +// Using a variable to hold the array length (instead of in.length()): +// real 0m2.972s user 0m2.527s sys 0m0.433s +// Using values from the table instead of isspace() (final) +// real 0m2.513s user 0m2.059s sys 0m0.439s +// +// The table has one entry per char value (0-256). Invalid base64 +// chars take value 256, whitespace 255, Pad ('=') 254. +// Valid char points contain their base64 value (0-63) +static const int b64values[] = { +/* 0 */ 256,/* 1 */ 256,/* 2 */ 256,/* 3 */ 256,/* 4 */ 256, +/* 5 */ 256,/* 6 */ 256,/* 7 */ 256,/* 8 */ 256, +/*9 ht */ 255,/* 10 nl */ 255,/* 11 vt */ 255,/* 12 np/ff*/ 255,/* 13 cr */ 255, +/* 14 */ 256,/* 15 */ 256,/* 16 */ 256,/* 17 */ 256,/* 18 */ 256,/* 19 */ 256, +/* 20 */ 256,/* 21 */ 256,/* 22 */ 256,/* 23 */ 256,/* 24 */ 256,/* 25 */ 256, +/* 26 */ 256,/* 27 */ 256,/* 28 */ 256,/* 29 */ 256,/* 30 */ 256,/* 31 */ 256, +/* 32 sp */ 255, +/* ! */ 256,/* " */ 256,/* # */ 256,/* $ */ 256,/* % */ 256, +/* & */ 256,/* ' */ 256,/* ( */ 256,/* ) */ 256,/* * */ 256, +/* + */ 62, +/* , */ 256,/* - */ 256,/* . */ 256, +/* / */ 63, +/* 0 */ 52,/* 1 */ 53,/* 2 */ 54,/* 3 */ 55,/* 4 */ 56,/* 5 */ 57,/* 6 */ 58, +/* 7 */ 59,/* 8 */ 60,/* 9 */ 61, +/* : */ 256,/* ; */ 256,/* < */ 256, +/* = */ 254, +/* > */ 256,/* ? */ 256,/* @ */ 256, +/* A */ 0,/* B */ 1,/* C */ 2,/* D */ 3,/* E */ 4,/* F */ 5,/* G */ 6,/* H */ 7, +/* I */ 8,/* J */ 9,/* K */ 10,/* L */ 11,/* M */ 12,/* N */ 13,/* O */ 14, +/* P */ 15,/* Q */ 16,/* R */ 17,/* S */ 18,/* T */ 19,/* U */ 20,/* V */ 21, +/* W */ 22,/* X */ 23,/* Y */ 24,/* Z */ 25, +/* [ */ 256,/* \ */ 256,/* ] */ 256,/* ^ */ 256,/* _ */ 256,/* ` */ 256, +/* a */ 26,/* b */ 27,/* c */ 28,/* d */ 29,/* e */ 30,/* f */ 31,/* g */ 32, +/* h */ 33,/* i */ 34,/* j */ 35,/* k */ 36,/* l */ 37,/* m */ 38,/* n */ 39, +/* o */ 40,/* p */ 41,/* q */ 42,/* r */ 43,/* s */ 44,/* t */ 45,/* u */ 46, +/* v */ 47,/* w */ 48,/* x */ 49,/* y */ 50,/* z */ 51, +/* { */ 256,/* | */ 256,/* } */ 256,/* ~ */ 256, +256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256, +256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256, +256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256, +256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256, +256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256, +256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256,256, +256,256,256,256,256,256,256,256, +}; static const char Base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; static const char Pad64 = '='; + bool base64_decode(const string& in, string& out) { int io = 0, state = 0, ch = 0; - const char *pos; unsigned int ii = 0; out.erase(); - out.reserve(in.length()); + size_t ilen = in.length(); + out.reserve(ilen); - for (ii = 0; ii < in.length(); ii++) { - ch = in[ii]; - if (isspace((unsigned char)ch)) /* Skip whitespace anywhere. */ + for (ii = 0; ii < ilen; ii++) { + ch = (unsigned char)in[ii]; + int value = b64values[ch]; + + if (value == 255) /* Skip whitespace anywhere. */ continue; - if (ch == Pad64) break; - - pos = strchr(Base64, ch); - if (pos == 0) { + if (value == 256) { /* A non-base64 character. */ DPRINT((stderr, "base64_dec: non-base64 char at pos %d\n", ii)); return false; } - switch (state) { case 0: - out += (pos - Base64) << 2; + out += value << 2; state = 1; break; case 1: - out[io] |= (pos - Base64) >> 4; - out += ((pos - Base64) & 0x0f) << 4 ; + out[io] |= value >> 4; + out += (value & 0x0f) << 4 ; io++; state = 2; break; case 2: - out[io] |= (pos - Base64) >> 2; - out += ((pos - Base64) & 0x03) << 6; + out[io] |= value >> 2; + out += (value & 0x03) << 6; io++; state = 3; break; case 3: - out[io] |= (pos - Base64); + out[io] |= value; io++; state = 0; break; default: - DPRINT((stderr, "base64_dec: internal!bad state!\n")); + fprintf(stderr, "base64_dec: internal!bad state!\n"); return false; } } @@ -154,7 +204,7 @@ bool base64_decode(const string& in, string& out) } DPRINT((stderr, "base64_dec: ret ok, io %d sz %d len %d value [%s]\n", - io, out.size(), out.length(), out.c_str())); + io, (int)out.size(), (int)out.length(), out.c_str())); return true; }