X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/72a23c9797290f1f2c948cf3027d80fa5c9370bc..41cce2f604996c7713d9025f8a719ea56d83783e:/src/symtab.c?ds=sidebyside

diff --git a/src/symtab.c b/src/symtab.c
index 59adf1f6..2eb2368f 100644
--- a/src/symtab.c
+++ b/src/symtab.c
@@ -20,43 +20,185 @@
 
 
 #include "system.h"
+#include "quotearg.h"
 #include "hash.h"
+#include "complain.h"
 #include "symtab.h"
 #include "gram.h"
 
+/*------------------------.
+| Distinguished symbols.  |
+`------------------------*/
+
+symbol_t *errtoken = NULL;
+symbol_t *undeftoken = NULL;
+symbol_t *endtoken = NULL;
+symbol_t *accept = NULL;
+symbol_t *startsymbol = NULL;
+location_t startsymbol_location;
+
 /*---------------------------------.
 | Create a new symbol, named TAG.  |
 `---------------------------------*/
 
-static bucket *
-bucket_new (const char *tag)
+static symbol_t *
+symbol_new (const char *tag, location_t location)
 {
-  bucket *res = XMALLOC (bucket, 1);
+  symbol_t *res = XMALLOC (symbol_t, 1);
 
   res->tag = xstrdup (tag);
+  res->location = location;
+
   res->type_name = NULL;
-  res->number = -1;
+  res->destructor = NULL;
+  res->printer = NULL;
+
+  res->number = NUMBER_UNDEFINED;
   res->prec = 0;
-  res->assoc = right_assoc;
-  res->user_token_number = SUNDEF;
+  res->assoc = undef_assoc;
+  res->user_token_number = USER_NUMBER_UNDEFINED;
+
   res->alias = NULL;
   res->class = unknown_sym;
 
-  if (getenv ("DEBUG"))
-    fprintf (stderr, "Creating: nsyms = %d, ntokens = %d: %s\n",
-	     nsyms, ntokens, tag);
   nsyms++;
-
   return res;
 }
 
 
+/*------------------------------------------------------------------.
+| Set the TYPE_NAME associated to SYMBOL.  Does nothing if passed 0 |
+| as TYPE_NAME.                                                     |
+`------------------------------------------------------------------*/
+
+void
+symbol_type_set (symbol_t *symbol, char *type_name, location_t location)
+{
+  if (type_name)
+    {
+      if (symbol->type_name)
+	complain_at (location,
+		     _("type redeclaration for %s"), symbol->tag);
+      symbol->type_name = type_name;
+    }
+}
+
+
+/*-------------------------------------------------------------------.
+| Set the DESTRUCTOR associated to SYMBOL.  Do nothing if passed 0.  |
+`-------------------------------------------------------------------*/
+
+void
+symbol_destructor_set (symbol_t *symbol, char *destructor, location_t location)
+{
+  if (destructor)
+    {
+      if (symbol->destructor)
+	complain_at (location,
+		     _("%s redeclaration for %s"),
+		     "%destructor", symbol->tag);
+      symbol->destructor = destructor;
+      symbol->destructor_location = location;
+    }
+}
+
+
+/*----------------------------------------------------------------.
+| Set the PRITNER associated to SYMBOL.  Do nothing if passed 0.  |
+`----------------------------------------------------------------*/
+
+void
+symbol_printer_set (symbol_t *symbol, char *printer, location_t location)
+{
+  if (printer)
+    {
+      if (symbol->printer)
+	complain_at (location,
+		     _("%s redeclaration for %s"),
+		     "%printer", symbol->tag);
+      symbol->printer = printer;
+      symbol->printer_location = location;
+    }
+}
+
+
+/*------------------------------------------------------------------.
+| Set the PRECEDENCE associated to SYMBOL.  Does nothing if invoked |
+| with UNDEF_ASSOC as ASSOC.                                        |
+`------------------------------------------------------------------*/
+
+void
+symbol_precedence_set (symbol_t *symbol,
+		       int prec, assoc_t assoc, location_t location)
+{
+  if (assoc != undef_assoc)
+    {
+      if (symbol->prec != 0)
+	complain_at (location,
+		     _("redefining precedence of %s"),
+		     symbol->tag);
+      symbol->prec = prec;
+      symbol->assoc = assoc;
+    }
+
+  /* Only terminals have a precedence. */
+  symbol_class_set (symbol, token_sym, location);
+}
+
+
+/*-------------------------------------.
+| Set the CLASS associated to SYMBOL.  |
+`-------------------------------------*/
+
+void
+symbol_class_set (symbol_t *symbol, symbol_class class, location_t location)
+{
+  if (symbol->class != unknown_sym && symbol->class != class)
+    complain_at (location, _("symbol %s redefined"), symbol->tag);
+
+  if (class == nterm_sym && symbol->class != nterm_sym)
+    symbol->number = nvars++;
+  else if (class == token_sym && symbol->number == NUMBER_UNDEFINED)
+    symbol->number = ntokens++;
+
+  symbol->class = class;
+}
+
+
+/*-------------------------------------------------.
+| Set the USER_TOKEN_NUMBER associated to SYMBOL.  |
+`-------------------------------------------------*/
+
+void
+symbol_user_token_number_set (symbol_t *symbol,
+			      int user_token_number, location_t location)
+{
+  assert (symbol->class == token_sym);
+
+  if (symbol->user_token_number != USER_NUMBER_UNDEFINED
+      && symbol->user_token_number != user_token_number)
+    complain_at (location, _("redefining user token number of %s"),
+		 symbol->tag);
+
+  symbol->user_token_number = user_token_number;
+  /* User defined $end token? */
+  if (user_token_number == 0)
+    {
+      endtoken = symbol;
+      endtoken->number = 0;
+      /* It is always mapped to 0, so it was already counted in
+	 NTOKENS.  */
+      --ntokens;
+    }
+}
+
+
 /*------------.
 | Free THIS.  |
 `------------*/
 
 static void
-bucket_free (bucket *this)
+symbol_free (symbol_t *this)
 {
 #if 0
   /* This causes crashes because one string can appear more
@@ -68,41 +210,201 @@ bucket_free (bucket *this)
 }
 
 
+/*-----------------------------------------------------------.
+| If THIS is not defined, report an error, and consider it a |
+| nonterminal.                                               |
+`-----------------------------------------------------------*/
+
+static bool
+symbol_check_defined (symbol_t *this)
+{
+  if (this->class == unknown_sym)
+    {
+      complain_at
+	(this->location,
+	 _("symbol %s is used, but is not defined as a token and has no rules"),
+	 this->tag);
+      this->class = nterm_sym;
+      this->number = nvars++;
+    }
+
+  return true;
+}
+
+
+/*-------------------------------------------------------------------.
+| Declare the new SYMBOL.  Make it an alias of SYMVAL, and type them |
+| with TYPENAME.                                                     |
+`-------------------------------------------------------------------*/
+
+void
+symbol_make_alias (symbol_t *symbol, symbol_t *symval, location_t loc)
+{
+  if (symval->alias)
+    warn_at (loc, _("symbol `%s' used more than once as a literal string"),
+	  symval->tag);
+  else if (symbol->alias)
+    warn_at (loc, _("symbol `%s' given more than one literal string"),
+	  symbol->tag);
+  else
+    {
+      symval->class = token_sym;
+      symval->user_token_number = symbol->user_token_number;
+      symbol->user_token_number = USER_NUMBER_ALIAS;
+      symval->alias = symbol;
+      symbol->alias = symval;
+      /* symbol and symval combined are only one symbol */
+      nsyms--;
+      ntokens--;
+      assert (ntokens == symbol->number || ntokens == symval->number);
+      symbol->number = symval->number =
+	(symval->number < symbol->number) ? symval->number : symbol->number;
+    }
+}
+
+
+/*---------------------------------------------------------.
+| Check that THIS, and its alias, have same precedence and |
+| associativity.                                           |
+`---------------------------------------------------------*/
+
+static bool
+symbol_check_alias_consistence (symbol_t *this)
+{
+  /* Check only those who _are_ the aliases. */
+  if (this->alias && this->user_token_number == USER_NUMBER_ALIAS)
+    {
+      if (this->prec != this->alias->prec)
+	{
+	  if (this->prec != 0 && this->alias->prec != 0)
+	    complain_at (this->alias->location,
+			 _("conflicting precedences for %s and %s"),
+			 this->tag, this->alias->tag);
+	  if (this->prec != 0)
+	    this->alias->prec = this->prec;
+	  else
+	    this->prec = this->alias->prec;
+	}
+
+      if (this->assoc != this->alias->assoc)
+	{
+	  if (this->assoc != undef_assoc && this->alias->assoc != undef_assoc)
+	    complain_at (this->alias->location,
+			 _("conflicting associativities for %s (%s) and %s (%s)"),
+			 this->tag, assoc_to_string (this->assoc),
+			 this->alias->tag, assoc_to_string (this->alias->assoc));
+	  if (this->assoc != undef_assoc)
+	    this->alias->assoc = this->assoc;
+	  else
+	    this->assoc = this->alias->assoc;
+	}
+    }
+  return true;
+}
+
+
+/*-------------------------------------------------------------------.
+| Assign a symbol number, and write the definition of the token name |
+| into FDEFINES.  Put in SYMBOLS.                                    |
+`-------------------------------------------------------------------*/
+
+static bool
+symbol_pack (symbol_t *this)
+{
+  if (this->class == nterm_sym)
+    {
+      this->number += ntokens;
+    }
+  else if (this->alias)
+    {
+      /* This symbol and its alias are a single token defn.
+	 Allocate a tokno, and assign to both check agreement of
+	 prec and assoc fields and make both the same */
+      if (this->number == NUMBER_UNDEFINED)
+	{
+	  if (this == endtoken || this->alias == endtoken)
+	    this->number = this->alias->number = 0;
+	  else
+	    {
+	      assert (this->alias->number != NUMBER_UNDEFINED);
+	      this->number = this->alias->number;
+	    }
+	}
+      /* Do not do processing below for USER_NUMBER_ALIASs.  */
+      if (this->user_token_number == USER_NUMBER_ALIAS)
+	return true;
+    }
+  else /* this->class == token_sym */
+    {
+      assert (this->number != NUMBER_UNDEFINED);
+    }
+
+  symbols[this->number] = this;
+  return true;
+}
+
+
+
+
+/*--------------------------------------------------.
+| Put THIS in TOKEN_TRANSLATIONS if it is a token.  |
+`--------------------------------------------------*/
+
+static bool
+symbol_translation (symbol_t *this)
+{
+  /* Non-terminal? */
+  if (this->class == token_sym
+      && this->user_token_number != USER_NUMBER_ALIAS)
+    {
+      /* A token which translation has already been set? */
+      if (token_translations[this->user_token_number] != undeftoken->number)
+	complain_at (this->location,
+		     _("tokens %s and %s both assigned number %d"),
+		     symbols[token_translations[this->user_token_number]]->tag,
+		     this->tag, this->user_token_number);
+
+      token_translations[this->user_token_number] = this->number;
+    }
+
+  return true;
+}
+
 
 /*----------------------.
-| A bucket hash table.  |
+| A symbol hash table.  |
 `----------------------*/
 
-/* Initial capacity of buckets hash table.  */
+/* Initial capacity of symbols hash table.  */
 #define HT_INITIAL_CAPACITY 257
 
-static struct hash_table *bucket_table = NULL;
+static struct hash_table *symbol_table = NULL;
 
 static bool
-hash_compare_bucket (const bucket *m1, const bucket *m2)
+hash_compare_symbol_t (const symbol_t *m1, const symbol_t *m2)
 {
-  return strcmp (m1->tag, m2->tag) ? FALSE : TRUE;
+  return strcmp (m1->tag, m2->tag) == 0;
 }
 
 static unsigned int
-hash_bucket (const bucket *m, unsigned int tablesize)
+hash_symbol_t (const symbol_t *m, unsigned int tablesize)
 {
   return hash_string (m->tag, tablesize);
 }
 
 
 /*-------------------------------.
-| Create the bucket hash table.  |
+| Create the symbol hash table.  |
 `-------------------------------*/
 
 void
-buckets_new (void)
+symbols_new (void)
 {
-  bucket_table = hash_initialize (HT_INITIAL_CAPACITY,
+  symbol_table = hash_initialize (HT_INITIAL_CAPACITY,
 				  NULL,
-				  (Hash_hasher) hash_bucket,
-				  (Hash_comparator) hash_compare_bucket,
-				  (Hash_data_freer) bucket_free);
+				  (Hash_hasher) hash_symbol_t,
+				  (Hash_comparator) hash_compare_symbol_t,
+				  (Hash_data_freer) symbol_free);
 }
 
 
@@ -111,45 +413,162 @@ buckets_new (void)
 | yet, create it.                                                 |
 `----------------------------------------------------------------*/
 
-bucket *
-getsym (const char *key)
+symbol_t *
+symbol_get (const char *key, location_t location)
 {
-  bucket probe;
-  bucket *entry;
+  symbol_t probe;
+  symbol_t *entry;
 
-  (const char *) probe.tag = key;
-  entry = hash_lookup (bucket_table, &probe);
+  /* Keep the symbol in a printable form.  */
+  key = quotearg_style (escape_quoting_style, key);
+  *(char const **) &probe.tag = key;
+  entry = hash_lookup (symbol_table, &probe);
 
   if (!entry)
     {
       /* First insertion in the hash. */
-      entry = bucket_new (key);
-      hash_insert (bucket_table, entry);
+      entry = symbol_new (key, location);
+      hash_insert (symbol_table, entry);
     }
   return entry;
 }
 
 
+/*------------------------------------------------------------------.
+| Generate a dummy nonterminal, whose name cannot conflict with the |
+| user's names.                                                     |
+`------------------------------------------------------------------*/
+
+symbol_t *
+dummy_symbol_get (location_t location)
+{
+  /* Incremented for each generated symbol.  */
+  static int dummy_count = 0;
+  static char buf[256];
+
+  symbol_t *sym;
+
+  sprintf (buf, "@%d", ++dummy_count);
+  sym = symbol_get (buf, location);
+  sym->class = nterm_sym;
+  sym->number = nvars++;
+  return sym;
+}
+
+
 /*-------------------.
-| Free the buckets.  |
+| Free the symbols.  |
 `-------------------*/
 
 void
-buckets_free (void)
+symbols_free (void)
 {
-  hash_free (bucket_table);
+  hash_free (symbol_table);
+  free (symbols);
 }
 
 
 /*---------------------------------------------------------------.
-| Look for undefined buckets, report an error, and consider them |
+| Look for undefined symbols, report an error, and consider them |
 | terminals.                                                     |
 `---------------------------------------------------------------*/
 
 void
-buckets_do (bucket_processor processor, void *processor_data)
+symbols_do (symbol_processor processor, void *processor_data)
 {
-  hash_do_for_each (bucket_table,
+  hash_do_for_each (symbol_table,
 		    (Hash_processor) processor,
 		    processor_data);
 }
+
+
+/*--------------------------------------------------------------.
+| Check that all the symbols are defined.  Report any undefined |
+| symbols and consider them nonterminals.                       |
+`--------------------------------------------------------------*/
+
+void
+symbols_check_defined (void)
+{
+  symbols_do (symbol_check_defined, NULL);
+}
+
+/*------------------------------------------------------------------.
+| Set TOKEN_TRANSLATIONS.  Check that no two symbols share the same |
+| number.                                                           |
+`------------------------------------------------------------------*/
+
+static void
+symbols_token_translations_init (void)
+{
+  bool num_256_available_p = true;
+  int i;
+
+  /* Find the highest user token number, and whether 256, the POSIX
+     preferred user token number for the error token, is used.  */
+  max_user_token_number = 0;
+  for (i = 0; i < ntokens; ++i)
+    {
+      symbol_t *this = symbols[i];
+      if (this->user_token_number != USER_NUMBER_UNDEFINED)
+	{
+	  if (this->user_token_number > max_user_token_number)
+	    max_user_token_number = this->user_token_number;
+	  if (this->user_token_number == 256)
+	    num_256_available_p = false;
+	}
+    }
+
+  /* If 256 is not used, assign it to error, to follow POSIX.  */
+  if (num_256_available_p
+      && errtoken->user_token_number == USER_NUMBER_UNDEFINED)
+    errtoken->user_token_number = 256;
+
+  /* Set the missing user numbers. */
+  if (max_user_token_number < 256)
+    max_user_token_number = 256;
+
+  for (i = 0; i < ntokens; ++i)
+    {
+      symbol_t *this = symbols[i];
+      if (this->user_token_number == USER_NUMBER_UNDEFINED)
+	this->user_token_number = ++max_user_token_number;
+      if (this->user_token_number > max_user_token_number)
+	max_user_token_number = this->user_token_number;
+    }
+
+  token_translations = XCALLOC (symbol_number_t, max_user_token_number + 1);
+
+  /* Initialize all entries for literal tokens to 2, the internal
+     token number for $undefined, which represents all invalid inputs.
+     */
+  for (i = 0; i < max_user_token_number + 1; i++)
+    token_translations[i] = undeftoken->number;
+  symbols_do (symbol_translation, NULL);
+}
+
+
+/*----------------------------------------------------------------.
+| Assign symbol numbers, and write definition of token names into |
+| FDEFINES.  Set up vectors SYMBOL_TABLE, TAGS of symbols.        |
+`----------------------------------------------------------------*/
+
+void
+symbols_pack (void)
+{
+  symbols = XCALLOC (symbol_t *, nsyms);
+
+  symbols_do (symbol_check_alias_consistence, NULL);
+  symbols_do (symbol_pack, NULL);
+
+  symbols_token_translations_init ();
+
+  if (startsymbol->class == unknown_sym)
+    fatal_at (startsymbol_location,
+	      _("the start symbol %s is undefined"),
+	      startsymbol->tag);
+  else if (startsymbol->class == token_sym)
+    fatal_at (startsymbol_location,
+	      _("the start symbol %s is a token"),
+	      startsymbol->tag);
+}