emileclarkb/hammer
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

add h_cfgrammar_free()

Browse source
This commit is contained in:
Sven M. Hallberg 2013-05-08 18:02:35 +02:00
parent 65ee3593bd
commit 9f5c32e205
2 changed files with 18 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

12
src/cfgrammar.c
View file

@ -1,6 +1,7 @@
/* Context-free grammar representation and analysis */
#include "cfgrammar.h"
#include "allocator.h"
#include <assert.h>
#include <ctype.h>
@ -10,6 +11,7 @@ HCFGrammar *h_cfgrammar_new(HAllocator *mm__)
HCFGrammar *g = h_new(HCFGrammar, 1);
assert(g != NULL);
g->mm__ = mm__;
g->arena = h_new_arena(mm__, 0); // default blocksize
g->nts = h_hashset_new(g->arena, h_eq_ptr, h_hash_ptr);
g->geneps = NULL;
@ -19,6 +21,16 @@ HCFGrammar *h_cfgrammar_new(HAllocator *mm__)
return g;
}
/* Frees the given grammar and associated data.
* Does *not* free parsers' CFG forms as created by h_desugar.
*/
void h_cfgrammar_free(HCFGrammar *g)
{
HAllocator *mm__ = g->mm__;
h_delete_arena(g->arena);
h_free(g);
}
// helpers
static void collect_nts(HCFGrammar *grammar, HCFChoice *symbol);

6
src/cfgrammar.h
View file

@ -11,6 +11,7 @@ typedef struct HCFGrammar_ {
HHashTable *first; // memoized first sets of the grammar's symbols
HHashTable *follow; // memoized follow sets of the grammar's NTs
HArena *arena;
HAllocator *mm__;
} HCFGrammar;
/* mapping input bytes or end to tokens
@ -29,6 +30,11 @@ static const HCFToken end_token = 0x200;
*/
HCFGrammar *h_cfgrammar(HAllocator* mm__, const HParser *parser);
/* Frees the given grammar and associated data.
* Does *not* free parsers' CFG forms as created by h_desugar.
*/
void h_cfgrammar_free(HCFGrammar *g);
/* Does the given symbol derive the empty string (under g)? */
bool h_symbol_derives_epsilon(HCFGrammar *g, const HCFChoice *symbol);