New file: skeleton for GLR (Generalized LR) parser.

[bison.git] / src / state.c

diff --git a/src/state.c b/src/state.c
index ed4a5082beb45cc72acf253f506ebfef6180373f..cb4cd5bcc6bdab8a1023f7d8cc89a70b41c53dc2 100644 (file)
--- a/src/state.c
+++ b/src/state.c
@@ -1,5 +1,5 @@
 /* Type definitions for nondeterministic finite state machine for bison,
-   Copyright 2001 Free Software Foundation, Inc.
+   Copyright (C) 2001, 2002  Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -20,6 +20,7 @@
 
 
 #include "system.h"
+#include "gram.h"
 #include "state.h"
 
 /*---------------------------------.
@@ -61,6 +62,55 @@ errs *
 errs_dup (errs *src)
 {
   errs *res = errs_new (src->nerrs);
-  memcpy (res->errs, src->errs, src->nerrs);
+  memcpy (res->errs, src->errs, src->nerrs * sizeof (src->errs[0]));
   return res;
 }
+
+/*-------------------------------------.
+| Create a new array of N reductions.  |
+`-------------------------------------*/
+
+#define REDUCTIONS_ALLOC(Nreductions)                                  \
+  (reductions *) xcalloc ((unsigned) (sizeof (reductions)              \
+                                  + (Nreductions - 1) * sizeof (short)), 1)
+
+reductions *
+reductions_new (int n)
+{
+  reductions *res = REDUCTIONS_ALLOC (n);
+  res->nreds = n;
+  return res;
+}
+
+
+/*--------------------------------------------------------------.
+| Print on OUT all the lookaheads such that this STATE wants to |
+| reduce this RULE.                                             |
+`--------------------------------------------------------------*/
+
+void
+state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out)
+{
+  int j, k;
+  int nlookaheads = 0;
+  /* Count the number of lookaheads corresponding to this rule.  */
+  for (j = 0; j < state->nlookaheads; ++j)
+    for (k = 0; k < ntokens; ++k)
+      if (bitset_test (state->lookaheads[j], k)
+         && state->lookaheads_rule[j]->number == rule->number)
+       nlookaheads++;
+
+  /* Print them if there are.  */
+  if (nlookaheads)
+    {
+      fprintf (out, "  [");
+      for (j = 0; j < state->nlookaheads; ++j)
+       for (k = 0; k < ntokens; ++k)
+         if (bitset_test (state->lookaheads[j], k)
+             && state->lookaheads_rule[j]->number == rule->number)
+           fprintf (out, "%s%s",
+                    symbol_tag_get (symbols[k]),
+                    --nlookaheads ? ", " : "");
+      fprintf (out, "]");
+    }
+}