diff options
Diffstat (limited to 'lib/httpserver/cencode.cpp')
-rw-r--r-- | lib/httpserver/cencode.cpp | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/lib/httpserver/cencode.cpp b/lib/httpserver/cencode.cpp new file mode 100644 index 00000000..b33c0683 --- /dev/null +++ b/lib/httpserver/cencode.cpp @@ -0,0 +1,113 @@ +/* +cencoder.c - c source to a base64 encoding algorithm implementation + +This is part of the libb64 project, and has been placed in the public domain. +For details, see http://sourceforge.net/projects/libb64 +*/ + +extern "C" +{ + +#include "cencode.h" + +const int CHARS_PER_LINE = 72; + +void base64_init_encodestate(base64_encodestate* state_in) +{ + state_in->step = step_A; + state_in->result = 0; + state_in->stepcount = 0; +} + +char base64_encode_value(char value_in) +{ + static const char* encoding = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + if (value_in > 63) return '='; + return encoding[(int)value_in]; +} + +int base64_encode_block(const char* plaintext_in, int length_in, char* code_out, base64_encodestate* state_in) +{ + const char* plainchar = plaintext_in; + const char* const plaintextend = plaintext_in + length_in; + char* codechar = code_out; + char result; + char fragment; + + result = state_in->result; + + switch (state_in->step) + { + while (1) + { + case step_A: + if (plainchar == plaintextend) + { + state_in->result = result; + state_in->step = step_A; + return codechar - code_out; + } + fragment = *plainchar++; + result = (fragment & 0x0fc) >> 2; + *codechar++ = base64_encode_value(result); + result = (fragment & 0x003) << 4; + case step_B: + if (plainchar == plaintextend) + { + state_in->result = result; + state_in->step = step_B; + return codechar - code_out; + } + fragment = *plainchar++; + result |= (fragment & 0x0f0) >> 4; + *codechar++ = base64_encode_value(result); + result = (fragment & 0x00f) << 2; + case step_C: + if (plainchar == plaintextend) + { + state_in->result = result; + state_in->step = step_C; + return codechar - code_out; + } + fragment = *plainchar++; + result |= (fragment & 0x0c0) >> 6; + *codechar++ = base64_encode_value(result); + result = (fragment & 0x03f) >> 0; + *codechar++ = base64_encode_value(result); + + ++(state_in->stepcount); + if (state_in->stepcount == CHARS_PER_LINE/4) + { + *codechar++ = '\n'; + state_in->stepcount = 0; + } + } + } + /* control should not reach here */ + return codechar - code_out; +} + +int base64_encode_blockend(char* code_out, base64_encodestate* state_in) +{ + char* codechar = code_out; + + switch (state_in->step) + { + case step_B: + *codechar++ = base64_encode_value(state_in->result); + *codechar++ = '='; + *codechar++ = '='; + break; + case step_C: + *codechar++ = base64_encode_value(state_in->result); + *codechar++ = '='; + break; + case step_A: + break; + } + *codechar++ = '\n'; + + return codechar - code_out; +} + +} |