shairport-sync/tinyhttp/chunk.c

80 lines
2.7 KiB
C

/*-
* Copyright 2012 Matthew Endsley
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
static const unsigned char http_chunk_state[] = {
/* * LF CR HEX */
0xC1, 0xC1, 0xC1, 1, /* s0: initial hex char */
0xC1, 0xC1, 2, 0x81, /* s1: additional hex chars, followed by CR */
0xC1, 0x83, 0xC1, 0xC1, /* s2: trailing LF */
0xC1, 0xC1, 4, 0xC1, /* s3: CR after chunk block */
0xC1, 0xC0, 0xC1, 0xC1, /* s4: LF after chunk block */
};
int http_parse_chunked(int* state, int *size, char ch)
{
int newstate, code = 0;
switch (ch) {
case '\n': code = 1; break;
case '\r': code = 2; break;
case '0': case '1': case '2': case '3':
case '4': case '5': case '6': case '7':
case '8': case '9': case 'a': case 'b':
case 'c': case 'd': case 'e': case 'f':
case 'A': case 'B': case 'C': case 'D':
case 'E': case 'F': code = 3; break;
}
newstate = http_chunk_state[*state * 4 + code];
*state = (newstate & 0xF);
switch (newstate) {
case 0xC0:
return *size != 0;
case 0xC1: /* error */
*size = -1;
return 0;
case 0x01: /* initial char */
*size = 0;
/* fallthrough */
case 0x81: /* size char */
if (ch >= 'a')
*size = *size * 16 + (ch - 'a' + 10);
else if (ch >= 'A')
*size = *size * 16 + (ch - 'A' + 10);
else
*size = *size * 16 + (ch - '0');
break;
case 0x83:
return *size == 0;
}
return 1;
}