100 lines
3 KiB
C
100 lines
3 KiB
C
/* Parser combinators for binary formats.
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* Copyright (C) 2012 Meredith L. Patterson, Dan "TQ" Hirsch
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation, version 2.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*/
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#include <assert.h>
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#include <ctype.h>
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#include <err.h>
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#include <limits.h>
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#include <stdarg.h>
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#include <string.h>
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#include "hammer.h"
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#include "internal.h"
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#include "allocator.h"
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#include "parsers/parser_internal.h"
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static uint32_t djbhash(const uint8_t *buf, size_t len) {
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uint32_t hash = 5381;
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while (len--) {
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hash = hash * 33 + *buf++;
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}
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return hash;
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}
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/* Helper function, since these lines appear in every parser */
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typedef struct {
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const HParser *p1;
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const HParser *p2;
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} HTwoParsers;
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static uint32_t cache_key_hash(const void* key) {
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return djbhash(key, sizeof(HParserCacheKey));
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}
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static bool cache_key_equal(const void* key1, const void* key2) {
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return memcmp(key1, key2, sizeof(HParserCacheKey)) == 0;
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}
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HParseResult* h_parse(const HParser* parser, const uint8_t* input, size_t length) {
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return h_parse__m(&system_allocator, parser, input, length);
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}
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HParseResult* h_parse__m(HAllocator* mm__, const HParser* parser, const uint8_t* input, size_t length) {
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// Set up a parse state...
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HArena * arena = h_new_arena(mm__, 0);
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HParseState *parse_state = a_new_(arena, HParseState, 1);
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parse_state->cache = h_hashtable_new(arena, cache_key_equal, // key_equal_func
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cache_key_hash); // hash_func
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parse_state->input_stream.input = input;
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parse_state->input_stream.index = 0;
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parse_state->input_stream.bit_offset = 8; // bit big endian
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parse_state->input_stream.overrun = 0;
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parse_state->input_stream.endianness = BIT_BIG_ENDIAN | BYTE_BIG_ENDIAN;
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parse_state->input_stream.length = length;
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parse_state->lr_stack = h_slist_new(arena);
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parse_state->recursion_heads = h_hashtable_new(arena, cache_key_equal,
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cache_key_hash);
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parse_state->arena = arena;
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HParseResult *res = h_do_parse(parser, parse_state);
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h_slist_free(parse_state->lr_stack);
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h_hashtable_free(parse_state->recursion_heads);
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// tear down the parse state
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h_hashtable_free(parse_state->cache);
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if (!res)
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h_delete_arena(parse_state->arena);
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return res;
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}
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void h_parse_result_free(HParseResult *result) {
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h_delete_arena(result->arena);
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}
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bool h_false(void* env) {
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(void)env;
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return false;
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}
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bool h_true(void* env) {
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(void)env;
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return true;
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}
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bool h_not_regular(HRVMProg *prog, void *env) {
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(void)env;
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return false;
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}
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