Added token type registry. Closes #45

src/registry.c

@@ -0,0 +1,87 @@
+/* Parser combinators for binary formats.
+ * Copyright (C) 2012  Meredith L. Patterson, Dan "TQ" Hirsch
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <search.h>
+#include <stdlib.h>
+#include "hammer.h"
+#include "internal.h"
+
+typedef struct Entry_ {
+  const char* name;
+  int value;
+} Entry;
+
+static void *tt_registry = NULL;
+static Entry** tt_by_id = NULL;
+static int tt_by_id_sz = 0;
+#define TT_START TT_USER
+static int tt_next = TT_START;
+
+/*
+  // TODO: These are for the extension registry, which does not yet have a good name.
+static void *ext_registry = NULL;
+static Entry** ext_by_id = NULL;
+static int ext_by_id_sz = 0;
+static int ext_next = 0;
+*/
+
+
+static int compare_entries(const void* v1, const void* v2) {
+  const Entry *e1 = (Entry*)v1, *e2 = (Entry*)v2;
+  return strcmp(e1->name, e2->name);
+}
+
+int h_allocate_token_type(const char* name) {
+  Entry* new_entry = malloc(sizeof(*new_entry));
+  new_entry->name = name;
+  new_entry->value = -1;
+  Entry* probe = *(Entry**)tsearch(new_entry, &tt_registry, compare_entries);
+  if (probe->value != -1) {
+    // Token type already exists...
+    // TODO: treat this as a bug?
+    free(new_entry);
+    return probe->value;
+  } else {
+    // new value
+    probe->name = strdup(probe->name); // drop ownership of name
+    probe->value = tt_next++;
+    if ((probe->value - TT_START) >= tt_by_id_sz) {
+      if (tt_by_id_sz == 0)
+	tt_by_id = malloc(sizeof(*tt_by_id) * ((tt_by_id_sz = (tt_next - TT_START) * 16)));
+      else
+	tt_by_id = realloc(tt_by_id, sizeof(*tt_by_id) * ((tt_by_id_sz *= 2)));
+    }
+    assert(probe->value - TT_START < tt_by_id_sz);
+    tt_by_id[probe->value - TT_START] = probe;
+    return probe->value;
+  }
+}
+int h_get_token_type_number(const char* name) {
+  Entry e;
+  e.name = name;
+  Entry **ret = (Entry**)tfind(&e, &tt_registry, compare_entries);
+  if (ret == NULL)
+    return -1;
+  else
+    return (*ret)->value;
+}
+const char* h_get_token_type_name(int token_type) {
+  if (token_type >= tt_next || token_type < TT_START)
+    return NULL;
+  else
+    return tt_by_id[token_type - TT_START]->name;
+}