#include "getargs.h"
#include "files.h"
#include "symtab.h"
+#include "symlist.h"
#include "options.h"
-#include "lex.h"
#include "gram.h"
#include "complain.h"
#include "output.h"
#include "conflicts.h"
#include "muscle_tab.h"
-typedef struct symbol_list
-{
- struct symbol_list *next;
- symbol_t *sym;
- int line;
-
- /* The action is attached to the LHS of a rule. */
- const char *action;
- int action_line;
-
- symbol_t *ruleprec;
-} symbol_list;
-
int lineno;
-static symbol_list *grammar = NULL;
+static symbol_list_t *grammar = NULL;
static int start_flag = 0;
/* Nonzero if %union has been seen. */
-static int typed = 0;
-
-/* Incremented for each %left, %right or %nonassoc seen */
-static int lastprec = 0;
-
-static symbol_list *
-symbol_list_new (symbol_t *sym)
-{
- symbol_list *res = XMALLOC (symbol_list, 1);
- res->next = NULL;
- res->sym = sym;
- res->line = lineno;
- res->action = NULL;
- res->action_line = 0;
- res->ruleprec = NULL;
- return res;
-}
-
-/*===================\
-| Low level lexing. |
-\===================*/
+int typed = 0;
+\f
+/*-----------------------.
+| Set the start symbol. |
+`-----------------------*/
-static void
-skip_to_char (int target)
+void
+grammar_start_symbol_set (symbol_t *s, location_t l)
{
- int c;
- if (target == '\n')
- complain (_(" Skipping to next \\n"));
+ if (start_flag)
+ complain (_("multiple %s declarations"), "%start");
else
- complain (_(" Skipping to next %c"), target);
-
- do
- c = skip_white_space ();
- while (c != target && c != EOF);
- if (c != EOF)
- ungetc (c, finput);
-}
-
-
-/*---------------------------------------------------------.
-| Read a signed integer from STREAM and return its value. |
-`---------------------------------------------------------*/
-
-static inline int
-read_signed_integer (FILE *stream)
-{
- int c = getc (stream);
- int sign = 1;
- int n = 0;
-
- if (c == '-')
- {
- c = getc (stream);
- sign = -1;
- }
-
- while (isdigit (c))
{
- n = 10 * n + (c - '0');
- c = getc (stream);
+ start_flag = 1;
+ startsymbol = s;
+ startsymbol_location = l;
}
-
- ungetc (c, stream);
-
- return sign * n;
}
-\f
-/*--------------------------------------------------------------.
-| Get the data type (alternative in the union) of the value for |
-| symbol N in rule RULE. |
-`--------------------------------------------------------------*/
-static char *
-get_type_name (int n, symbol_list *rule)
-{
- int i;
- symbol_list *rp;
-
- if (n < 0)
- {
- complain (_("invalid $ value"));
- return NULL;
- }
-
- rp = rule;
- i = 0;
- while (i < n)
- {
- rp = rp->next;
- if (rp == NULL || rp->sym == NULL)
- {
- complain (_("invalid $ value"));
- return NULL;
- }
- ++i;
- }
-
- return rp->sym->type_name;
-}
-\f
-/*------------------------------------------------------------------.
-| Copy the character C to OOUT, and insert quadigraphs when needed. |
-`------------------------------------------------------------------*/
-
-static inline void
-copy_character (struct obstack *oout, int c)
-{
- switch (c)
- {
- case '[':
- obstack_sgrow (oout, "@<:@");
- break;
-
- case ']':
- obstack_sgrow (oout, "@:>@");
- break;
-
- default:
- obstack_1grow (oout, c);
- }
-}
-
-/*------------------------------------------------------------.
-| Dump the string from FIN to OOUT if non null. MATCH is the |
-| delimiter of the string (either ' or "). |
-`------------------------------------------------------------*/
+/*----------------------------------------------------------------.
+| There are two prologues: one before %union, one after. Augment |
+| the current one. |
+`----------------------------------------------------------------*/
-static inline void
-copy_string2 (FILE *fin, struct obstack *oout, int match, int store)
+void
+prologue_augment (const char *prologue, location_t location)
{
- int c;
-
- if (store)
- obstack_1grow (oout, match);
+ struct obstack *oout =
+ !typed ? &pre_prologue_obstack : &post_prologue_obstack;
- c = getc (fin);
-
- while (c != match)
+ if (!no_lines_flag)
{
- if (c == EOF)
- fatal (_("unterminated string at end of file"));
- if (c == '\n')
- {
- complain (_("unterminated string"));
- ungetc (c, fin);
- c = match; /* invent terminator */
- continue;
- }
-
- copy_character (oout, c);
-
- if (c == '\\')
- {
- c = getc (fin);
- if (c == EOF)
- fatal (_("unterminated string at end of file"));
- copy_character (oout, c);
-
- if (c == '\n')
- ++lineno;
- }
-
- c = getc (fin);
+ obstack_fgrow2 (oout, muscle_find ("linef"),
+ location.first_line,
+ quotearg_style (c_quoting_style,
+ muscle_find ("filename")));
}
-
- if (store)
- obstack_1grow (oout, c);
+ obstack_sgrow (oout, prologue);
}
-/* FIXME. */
-static inline void
-copy_string (FILE *fin, struct obstack *oout, int match)
-{
- copy_string2 (fin, oout, match, 1);
-}
-/* FIXME. */
-
-static inline void
-copy_identifier (FILE *fin, struct obstack *oout)
-{
- int c;
-
- while (isalnum (c = getc (fin)) || c == '_')
- obstack_1grow (oout, c);
-
- ungetc (c, fin);
-}
+/*----------------------.
+| Handle the epilogue. |
+`----------------------*/
-/*------------------------------------------------------------------.
-| Dump the wannabee comment from IN to OOUT. In fact we just saw a |
-| `/', which might or might not be a comment. In any case, copy |
-| what we saw. |
-`------------------------------------------------------------------*/
-
-static inline void
-copy_comment (FILE *fin, struct obstack *oout)
+void
+epilogue_set (const char *epilogue, location_t location)
{
- int cplus_comment;
- int ended;
- int c;
-
- /* We read a `/', output it. */
- obstack_1grow (oout, '/');
-
- switch ((c = getc (fin)))
- {
- case '/':
- cplus_comment = 1;
- break;
- case '*':
- cplus_comment = 0;
- break;
- default:
- ungetc (c, fin);
- return;
- }
-
- obstack_1grow (oout, c);
- c = getc (fin);
-
- ended = 0;
- while (!ended)
+ if (!no_lines_flag)
{
- if (!cplus_comment && c == '*')
- {
- while (c == '*')
- {
- obstack_1grow (oout, c);
- c = getc (fin);
- }
-
- if (c == '/')
- {
- obstack_1grow (oout, c);
- ended = 1;
- }
- }
- else if (c == '\n')
- {
- ++lineno;
- obstack_1grow (oout, c);
- if (cplus_comment)
- ended = 1;
- else
- c = getc (fin);
- }
- else if (c == EOF)
- fatal (_("unterminated comment"));
- else
- {
- copy_character (oout, c);
- c = getc (fin);
- }
+ obstack_fgrow2 (&muscle_obstack, muscle_find ("linef"),
+ location.first_line,
+ quotearg_style (c_quoting_style,
+ muscle_find ("filename")));
}
+ obstack_sgrow (&muscle_obstack, epilogue);
+ obstack_1grow (&muscle_obstack, 0);
+ muscle_insert ("epilogue", obstack_finish (&muscle_obstack));
}
+\f
+
/*-------------------------------------------------------------------.
-| FIN is pointing to a location (i.e., a `@'). Output to OOUT a |
-| reference to this location. RULE_LENGTH is the number of values in |
-| the current rule so far, which says where to find `$0' with |
-| respect to the top of the stack. |
+| Generate a dummy symbol, a nonterminal, whose name cannot conflict |
+| with the user's names. |
`-------------------------------------------------------------------*/
-static inline void
-copy_at (FILE *fin, struct obstack *oout, int rule_length)
-{
- int c = getc (fin);
- locations_flag = 1;
-
- if (c == '$')
- {
- obstack_sgrow (oout, "]b4_lhs_location[");
- }
- else if (isdigit (c) || c == '-')
- {
- int n;
-
- ungetc (c, fin);
- n = read_signed_integer (fin);
- if (n > rule_length)
- complain (_("invalid value: %s%d"), "@", n);
- else
- obstack_fgrow2 (oout, "]b4_rhs_location([%d], [%d])[",
- rule_length, n);
- }
- else
- {
- char buf[] = "@c";
- buf[1] = c;
- complain (_("%s is invalid"), quote (buf));
- }
-}
-
-
-/*------------------------------------------------------------------.
-| FIN is pointing to a wannabee semantic value (i.e., a `$'). |
-| |
-| Possible inputs: $[<TYPENAME>]($|integer) |
-| |
-| Output to OOUT a reference to this semantic value. RULE_LENGTH is |
-| the number of values in the current rule so far, which says where |
-| to find `$0' with respect to the top of the stack. |
-`------------------------------------------------------------------*/
-
-static inline void
-copy_dollar (FILE *fin, struct obstack *oout,
- symbol_list *rule, int rule_length)
+static symbol_t *
+gensym (location_t location)
{
- int c = getc (fin);
- const char *type_name = NULL;
-
- /* Get the type name if explicit. */
- if (c == '<')
- {
- read_type_name (fin);
- type_name = token_buffer;
- c = getc (fin);
- }
+ /* Incremented for each generated symbol */
+ static int gensym_count = 0;
+ static char buf[256];
- if (c == '$')
- {
- if (!type_name)
- type_name = get_type_name (0, rule);
- if (!type_name && typed)
- complain (_("$$ of `%s' has no declared type"),
- rule->sym->tag);
- if (!type_name)
- type_name = "";
- obstack_fgrow1 (oout,
- "]b4_lhs_value([%s])[", type_name);
- }
- else if (isdigit (c) || c == '-')
- {
- int n;
- ungetc (c, fin);
- n = read_signed_integer (fin);
+ symbol_t *sym;
- if (n > rule_length)
- complain (_("invalid value: %s%d"), "$", n);
- else
- {
- if (!type_name && n > 0)
- type_name = get_type_name (n, rule);
- if (!type_name && typed)
- complain (_("$%d of `%s' has no declared type"),
- n, rule->sym->tag);
- if (!type_name)
- type_name = "";
- obstack_fgrow3 (oout, "]b4_rhs_value([%d], [%d], [%s])[",
- rule_length, n, type_name);
- }
- }
- else
- {
- char buf[] = "$c";
- buf[1] = c;
- complain (_("%s is invalid"), quote (buf));
- }
+ sprintf (buf, "@%d", ++gensym_count);
+ sym = getsym (buf, location);
+ sym->class = nterm_sym;
+ sym->number = nvars++;
+ return sym;
}
\f
/*-------------------------------------------------------------------.
-| Copy the contents of a `%{ ... %}' into the definitions file. The |
-| `%{' has already been read. Return after reading the `%}'. |
+| Parse the input grammar into a one symbol_list_t structure. Each |
+| rule is represented by a sequence of symbols: the left hand side |
+| followed by the contents of the right hand side, followed by a |
+| null pointer instead of a symbol to terminate the rule. The next |
+| symbol is the lhs of the following rule. |
+| |
+| All actions are copied out, labelled by the rule number they apply |
+| to. |
+| |
+| Bison used to allow some %directives in the rules sections, but |
+| this is no longer consider appropriate: (i) the documented grammar |
+| doesn't claim it, (ii), it would promote bad style, (iii), error |
+| recovery for %directives consists in skipping the junk until a `%' |
+| is seen and helrp synchronizing. This scheme is definitely wrong |
+| in the rules section. |
`-------------------------------------------------------------------*/
-static void
-copy_definition (struct obstack *oout)
-{
- int c;
- /* -1 while reading a character if prev char was %. */
- int after_percent;
-
- if (!no_lines_flag)
- {
- obstack_fgrow2 (oout, muscle_find ("linef"),
- lineno, quotearg_style (c_quoting_style,
- muscle_find ("filename")));
- }
-
- after_percent = 0;
-
- c = getc (finput);
-
- for (;;)
- {
- switch (c)
- {
- case '\n':
- obstack_1grow (oout, c);
- ++lineno;
- break;
-
- case '%':
- after_percent = -1;
- break;
+/* The (currently) last symbol of GRAMMAR. */
+symbol_list_t *grammar_end = NULL;
- case '\'':
- case '"':
- copy_string (finput, oout, c);
- break;
-
- case '/':
- copy_comment (finput, oout);
- break;
-
- case EOF:
- fatal ("%s", _("unterminated `%{' definition"));
-
- default:
- copy_character (oout, c);
- }
-
- c = getc (finput);
-
- if (after_percent)
- {
- if (c == '}')
- return;
- obstack_1grow (oout, '%');
- }
- after_percent = 0;
- }
-}
-
-
-/*------------------------------------------.
-| Parse what comes after %token or %nterm. |
-`------------------------------------------*/
-
-static void
-parse_token_decl (symbol_class class)
+/* Append S to the GRAMMAR. */
+void
+grammar_symbol_append (symbol_t *symbol, location_t location)
{
- token_t token = tok_undef;
- char *typename = NULL;
-
- /* The symbol being defined. */
- symbol_t *symbol = NULL;
+ symbol_list_t *p = symbol_list_new (symbol, location);
- /* After `%token' and `%nterm', any number of symbols maybe be
- defined. */
- for (;;)
- {
- int tmp_char = ungetc (skip_white_space (), finput);
-
- /* `%' (for instance from `%token', or from `%%' etc.) is the
- only valid means to end this declaration. */
- if (tmp_char == '%')
- return;
- if (tmp_char == EOF)
- fatal (_("Premature EOF after %s"), token_buffer);
-
- token = lex ();
- switch (token)
- {
- case tok_comma:
- symbol = NULL;
- break;
-
- case tok_typename:
- typename = xstrdup (token_buffer);
- symbol = NULL;
- break;
-
- case tok_identifier:
- if (*symval->tag == '\"' && symbol)
- {
- symbol_make_alias (symbol, symval, typename);
- symbol = NULL;
- }
- else
- {
- symbol = symval;
- symbol_class_set (symbol, class);
- if (typename)
- symbol_type_set (symbol, typename);
- }
- break;
-
- case tok_number:
- symbol_user_token_number_set (symbol, numval);
- break;
-
- default:
- complain (_("`%s' is invalid in %s"),
- token_buffer,
- (class == token_sym) ? "%token" : "%nterm");
- skip_to_char ('%');
- }
- }
+ if (grammar_end)
+ grammar_end->next = p;
+ else
+ grammar = p;
+ grammar_end = p;
}
+/* The rule currently being defined, and the previous rule.
+ CURRENT_RULE points to the first LHS of the current rule, while
+ PREVIOUS_RULE_END points to the *end* of the previous rule (NULL). */
+symbol_list_t *current_rule = NULL;
+symbol_list_t *previous_rule_end = NULL;
-/*------------------------------.
-| Parse what comes after %start |
-`------------------------------*/
-static void
-parse_start_decl (void)
+/*----------------------------------------------.
+| Create a new rule for LHS in to the GRAMMAR. |
+`----------------------------------------------*/
+
+void
+grammar_rule_begin (symbol_t *lhs, location_t location)
{
- if (start_flag)
- complain (_("multiple %s declarations"), "%start");
- if (lex () != tok_identifier)
- complain (_("invalid %s declaration"), "%start");
- else
+ if (!start_flag)
{
+ startsymbol = lhs;
+ startsymbol_location = location;
start_flag = 1;
- startsymbol = symval;
}
-}
-/*-----------------------------------------------------------.
-| read in a %type declaration and record its information for |
-| get_type_name to access |
-`-----------------------------------------------------------*/
+ /* Start a new rule and record its lhs. */
+ ++nrules;
+ ++nritems;
-static void
-parse_type_decl (void)
-{
- char *name;
+ previous_rule_end = grammar_end;
+ grammar_symbol_append (lhs, location);
+ current_rule = grammar_end;
- if (lex () != tok_typename)
- {
- complain ("%s", _("%type declaration has no <typename>"));
- skip_to_char ('%');
- return;
- }
+ /* Mark the rule's lhs as a nonterminal if not already so. */
- name = xstrdup (token_buffer);
-
- for (;;)
+ if (lhs->class == unknown_sym)
{
- token_t t;
- int tmp_char = ungetc (skip_white_space (), finput);
-
- if (tmp_char == '%')
- return;
- if (tmp_char == EOF)
- fatal (_("Premature EOF after %s"), token_buffer);
-
- t = lex ();
-
- switch (t)
- {
- case tok_comma:
- case tok_semicolon:
- break;
-
- case tok_identifier:
- symbol_type_set (symval, name);
- break;
-
- default:
- complain (_("invalid %%type declaration due to item: %s"),
- token_buffer);
- skip_to_char ('%');
- }
+ lhs->class = nterm_sym;
+ lhs->number = nvars;
+ ++nvars;
}
+ else if (lhs->class == token_sym)
+ complain (_("rule given for %s, which is a token"), lhs->tag);
}
-
-
-/*----------------------------------------------------------------.
-| Read in a %left, %right or %nonassoc declaration and record its |
-| information. |
-`----------------------------------------------------------------*/
+/* Check that the last rule (CURRENT_RULE) is properly defined. For
+ instance, there should be no type clash on the default action. */
static void
-parse_assoc_decl (associativity assoc)
+grammar_current_rule_check (void)
{
- char *name = NULL;
- int prev = 0;
+ symbol_t *lhs = current_rule->sym;
+ symbol_t *first_rhs = current_rule->next->sym;
- /* Assign a new precedence level, never 0. */
- ++lastprec;
+ /* If there is an action, then there is nothing we can do: the user
+ is allowed to shoot in her foot. */
+ if (current_rule->action)
+ return;
- for (;;)
+ /* If $$ is being set in default way, report if any type mismatch.
+ */
+ if (first_rhs)
{
- token_t t;
- int tmp_char = ungetc (skip_white_space (), finput);
-
- if (tmp_char == '%')
- return;
- if (tmp_char == EOF)
- fatal (_("Premature EOF after %s"), token_buffer);
-
- t = lex ();
-
- switch (t)
- {
- case tok_typename:
- name = xstrdup (token_buffer);
- break;
-
- case tok_comma:
- break;
-
- case tok_identifier:
- if (symval->class == nterm_sym)
- complain (_("symbol %s redefined"), symval->tag);
- if (symval->number == NUMBER_UNDEFINED)
- {
- symval->number = ntokens++;
- symval->class = token_sym;
- }
- symbol_precedence_set (symval, lastprec, assoc);
- if (name)
- symbol_type_set (symval, name);
- break;
-
- case tok_number:
- if (prev == tok_identifier)
- {
- symval->user_token_number = numval;
- }
- else
- {
- complain
- (_("invalid text (%s) - number should be after identifier"),
- token_buffer);
- skip_to_char ('%');
- }
- break;
-
- case tok_semicolon:
- return;
-
- default:
- complain (_("unexpected item: %s"), token_buffer);
- skip_to_char ('%');
- }
-
- prev = t;
+ const char *lhs_type = lhs->type_name ? lhs->type_name : "";
+ const char *rhs_type = first_rhs->type_name ? first_rhs->type_name : "";
+ if (strcmp (lhs_type, rhs_type))
+ complain (_("type clash (`%s' `%s') on default action"),
+ lhs_type, rhs_type);
}
-}
-
-
-
-/*--------------------------------------------------------------.
-| Copy the union declaration into the stype muscle |
-| (and fdefines), where it is made into the definition of |
-| YYSTYPE, the type of elements of the parser value stack. |
-`--------------------------------------------------------------*/
-
-static void
-parse_union_decl (void)
-{
- int c;
- int count = 0;
- bool done = FALSE;
- struct obstack union_obstack;
- if (typed)
- complain (_("multiple %s declarations"), "%union");
-
- typed = 1;
-
- MUSCLE_INSERT_INT ("stype_line", lineno);
- obstack_init (&union_obstack);
- obstack_sgrow (&union_obstack, "union");
-
- while (!done)
+ /* Warn if there is no default for $$ but we need one. */
+ else
{
- c = xgetc (finput);
-
- /* If C contains '/', it is output by copy_comment (). */
- if (c != '/')
- obstack_1grow (&union_obstack, c);
-
- switch (c)
- {
- case '\n':
- ++lineno;
- break;
-
- case '/':
- copy_comment (finput, &union_obstack);
- break;
-
- case '{':
- ++count;
- break;
-
- case '}':
- /* FIXME: Errr. How could this happen???. --akim */
- if (count == 0)
- complain (_("unmatched %s"), "`}'");
- count--;
- if (!count)
- done = TRUE;
- break;
- }
+ if (lhs->type_name)
+ complain (_("empty rule for typed nonterminal, and no action"));
}
-
- /* JF don't choke on trailing semi */
- c = skip_white_space ();
- if (c != ';')
- ungetc (c, finput);
- obstack_1grow (&union_obstack, 0);
- muscle_insert ("stype", obstack_finish (&union_obstack));
}
-/*-------------------------------------------------------.
-| Parse the declaration %expect N which says to expect N |
-| shift-reduce conflicts. |
-`-------------------------------------------------------*/
-
-static void
-parse_expect_decl (void)
-{
- int c = skip_white_space ();
- ungetc (c, finput);
-
- if (!isdigit (c))
- complain (_("argument of %%expect is not an integer"));
- else
- expected_conflicts = read_signed_integer (finput);
-}
-
+/*-------------------------------------.
+| End the currently being grown rule. |
+`-------------------------------------*/
-static void
-parse_muscle_decl (void)
+void
+grammar_rule_end (location_t location)
{
- int ch = ungetc (skip_white_space (), finput);
- char *muscle_key;
- char *muscle_value;
-
- /* Read key. */
- if (!isalpha (ch) && ch != '_')
- {
- complain (_("invalid %s declaration"), "%define");
- skip_to_char ('%');
- return;
- }
- copy_identifier (finput, &muscle_obstack);
- obstack_1grow (&muscle_obstack, 0);
- muscle_key = obstack_finish (&muscle_obstack);
-
- /* Read value. */
- ch = skip_white_space ();
- if (ch != '"')
- {
- ungetc (ch, finput);
- if (ch != EOF)
- {
- complain (_("invalid %s declaration"), "%define");
- skip_to_char ('%');
- return;
- }
- else
- fatal (_("Premature EOF after %s"), "\"");
- }
- copy_string2 (finput, &muscle_obstack, '"', 0);
- obstack_1grow (&muscle_obstack, 0);
- muscle_value = obstack_finish (&muscle_obstack);
-
- /* Store the (key, value) pair in the environment. */
- muscle_insert (muscle_key, muscle_value);
+ /* Put an empty link in the list to mark the end of this rule */
+ grammar_symbol_append (NULL, grammar_end->location);
+ current_rule->location = location;
+ grammar_current_rule_check ();
}
+/*-------------------------------------------------------------------.
+| The previous action turns out the be a mid-rule action. Attach it |
+| to the current rule, i.e., create a dummy symbol, attach it this |
+| mid-rule action, and append this dummy nonterminal to the current |
+| rule. |
+`-------------------------------------------------------------------*/
-/*---------------------------------.
-| Parse a double quoted parameter. |
-`---------------------------------*/
-
-static const char *
-parse_dquoted_param (const char *from)
+void
+grammar_midrule_action (void)
{
- struct obstack param_obstack;
- const char *param = NULL;
- int c;
-
- obstack_init (¶m_obstack);
- c = skip_white_space ();
-
- if (c != '"')
- {
- complain (_("invalid %s declaration"), from);
- ungetc (c, finput);
- skip_to_char ('%');
- return NULL;
- }
-
- while ((c = literalchar ()) != '"')
- obstack_1grow (¶m_obstack, c);
-
- obstack_1grow (¶m_obstack, '\0');
- param = obstack_finish (¶m_obstack);
-
- if (c != '"' || strlen (param) == 0)
- {
- complain (_("invalid %s declaration"), from);
- if (c != '"')
- ungetc (c, finput);
- skip_to_char ('%');
- return NULL;
- }
+ /* Since the action was written out with this rule's number, we must
+ give the new rule this number by inserting the new rule before
+ it. */
+
+ /* Make a DUMMY nonterminal, whose location is that of the midrule
+ action. Create the MIDRULE. */
+ location_t dummy_location = current_rule->action_location;
+ symbol_t *dummy = gensym (dummy_location);
+ symbol_list_t *midrule = symbol_list_new (dummy, dummy_location);
+
+ /* Make a new rule, whose body is empty, before the current one, so
+ that the action just read can belong to it. */
+ ++nrules;
+ ++nritems;
+ /* Attach its location and actions to that of the DUMMY. */
+ midrule->location = dummy_location;
+ midrule->action = current_rule->action;
+ midrule->action_location = dummy_location;
+ current_rule->action = NULL;
+
+ if (previous_rule_end)
+ previous_rule_end->next = midrule;
+ else
+ grammar = midrule;
- return param;
-}
+ /* End the dummy's rule. */
+ previous_rule_end = symbol_list_new (NULL, dummy_location);
+ previous_rule_end->next = current_rule;
-/*----------------------------------.
-| Parse what comes after %skeleton. |
-`----------------------------------*/
+ midrule->next = previous_rule_end;
-static void
-parse_skel_decl (void)
-{
- skeleton = parse_dquoted_param ("%skeleton");
+ /* Insert the dummy nonterminal replacing the midrule action into
+ the current rule. */
+ grammar_current_rule_symbol_append (dummy, dummy_location);
}
-/*----------------------------------------------------------------.
-| Read from finput until `%%' is seen. Discard the `%%'. Handle |
-| any `%' declarations, and copy the contents of any `%{ ... %}' |
-| groups to PRE_PROLOGUE_OBSTACK or POST_PROLOGUE_OBSTACK. |
-`----------------------------------------------------------------*/
-
-static void
-read_declarations (void)
-{
- for (;;)
- {
- int c = skip_white_space ();
-
- if (c == '%')
- {
- token_t tok = parse_percent_token ();
-
- switch (tok)
- {
- case tok_two_percents:
- return;
-
- case tok_percent_left_curly:
- if (!typed)
- copy_definition (&pre_prologue_obstack);
- else
- copy_definition (&post_prologue_obstack);
- break;
-
- case tok_token:
- parse_token_decl (token_sym);
- break;
-
- case tok_nterm:
- parse_token_decl (nterm_sym);
- break;
-
- case tok_type:
- parse_type_decl ();
- break;
-
- case tok_start:
- parse_start_decl ();
- break;
-
- case tok_union:
- parse_union_decl ();
- break;
-
- case tok_expect:
- parse_expect_decl ();
- break;
-
- case tok_left:
- parse_assoc_decl (left_assoc);
- break;
-
- case tok_right:
- parse_assoc_decl (right_assoc);
- break;
-
- case tok_nonassoc:
- parse_assoc_decl (non_assoc);
- break;
-
- case tok_define:
- parse_muscle_decl ();
- break;
-
- case tok_skel:
- parse_skel_decl ();
- break;
-
- case tok_noop:
- break;
-
- case tok_stropt:
- case tok_intopt:
- case tok_obsolete:
- assert (0);
- break;
-
- case tok_illegal:
- default:
- complain (_("unrecognized: %s"), token_buffer);
- skip_to_char ('%');
- }
- }
- else if (c == EOF)
- fatal (_("no input grammar"));
- else
- {
- char buf[] = "c";
- buf[0] = c;
- complain (_("unknown character: %s"), quote (buf));
- skip_to_char ('%');
- }
- }
-}
-\f
-/*------------------------------------------------------------------.
-| Assuming that a `{' has just been seen, copy everything up to the |
-| matching `}' into ACTION_OBSTACK. |
-| |
-| RULE_LENGTH is the number of values in the current rule so far, |
-| which says where to find `$0' with respect to the top of the |
-| stack. It is not the same as the rule->length in the case of mid |
-| rule actions. |
-| |
-| This routine is used for actions. |
-`------------------------------------------------------------------*/
+/* Set the precedence symbol of the current rule to PRECSYM. */
-static void
-parse_action (symbol_list *rule, int rule_length)
+void
+grammar_current_rule_prec_set (symbol_t *precsym)
{
- int count = 1;
- rule->action_line = lineno;
- while (count > 0)
- {
- int c;
- while ((c = getc (finput)) != '}')
- switch (c)
- {
- case '\n':
- copy_character (&action_obstack, c);
- ++lineno;
- break;
-
- case '{':
- copy_character (&action_obstack, c);
- ++count;
- break;
-
- case '\'':
- case '"':
- copy_string (finput, &action_obstack, c);
- break;
-
- case '/':
- copy_comment (finput, &action_obstack);
- break;
-
- case '$':
- copy_dollar (finput, &action_obstack, rule, rule_length);
- break;
-
- case '@':
- copy_at (finput, &action_obstack, rule_length);
- break;
-
- case EOF:
- fatal (_("unmatched %s"), "`{'");
-
- default:
- copy_character (&action_obstack, c);
- }
-
- /* Above loop exits when C is '}'. */
- if (--count)
- copy_character (&action_obstack, c);
- }
-
- obstack_1grow (&action_obstack, '\0');
- rule->action = obstack_finish (&action_obstack);
+ if (current_rule->ruleprec)
+ complain (_("two @prec's in a row"));
+ current_rule->ruleprec = precsym;
}
-\f
-
-/*-------------------------------------------------------------------.
-| Generate a dummy symbol, a nonterminal, whose name cannot conflict |
-| with the user's names. |
-`-------------------------------------------------------------------*/
+/* Attach a SYMBOL to the current rule. If needed, move the previous
+ action as a mid-rule action. */
-static symbol_t *
-gensym (void)
+void
+grammar_current_rule_symbol_append (symbol_t *symbol, location_t location)
{
- /* Incremented for each generated symbol */
- static int gensym_count = 0;
- static char buf[256];
-
- symbol_t *sym;
-
- sprintf (buf, "@%d", ++gensym_count);
- token_buffer = buf;
- sym = getsym (token_buffer);
- sym->class = nterm_sym;
- sym->number = nvars++;
- return sym;
+ if (current_rule->action)
+ grammar_midrule_action ();
+ ++nritems;
+ grammar_symbol_append (symbol, location);
}
-\f
-/*-------------------------------------------------------------------.
-| Parse the input grammar into a one symbol_list structure. Each |
-| rule is represented by a sequence of symbols: the left hand side |
-| followed by the contents of the right hand side, followed by a |
-| null pointer instead of a symbol to terminate the rule. The next |
-| symbol is the lhs of the following rule. |
-| |
-| All actions are copied out, labelled by the rule number they apply |
-| to. |
-| |
-| Bison used to allow some %directives in the rules sections, but |
-| this is no longer consider appropriate: (i) the documented grammar |
-| doesn't claim it, (ii), it would promote bad style, (iii), error |
-| recovery for %directives consists in skipping the junk until a `%' |
-| is seen and helrp synchronizing. This scheme is definitely wrong |
-| in the rules section. |
-`-------------------------------------------------------------------*/
-
-static void
-readgram (void)
-{
- token_t t;
- symbol_t *lhs = NULL;
- symbol_list *p = NULL;
- symbol_list *p1 = NULL;
-
- /* Points to first symbol_list of current rule. its symbol is the
- lhs of the rule. */
- symbol_list *crule = NULL;
- /* Points to the symbol_list preceding crule. */
- symbol_list *crule1 = NULL;
-
- t = lex ();
-
- while (t != tok_two_percents && t != tok_eof)
- if (t == tok_identifier || t == tok_bar)
- {
- int action_flag = 0;
- /* Number of symbols in rhs of this rule so far */
- int rulelength = 0;
- int xactions = 0; /* JF for error checking */
- symbol_t *first_rhs = 0;
-
- if (t == tok_identifier)
- {
- lhs = symval;
-
- if (!start_flag)
- {
- startsymbol = lhs;
- start_flag = 1;
- }
-
- t = lex ();
- if (t != tok_colon)
- {
- complain (_("ill-formed rule: initial symbol not followed by colon"));
- unlex (t);
- }
- }
-
- if (nrules == 0 && t == tok_bar)
- {
- complain (_("grammar starts with vertical bar"));
- lhs = symval; /* BOGUS: use a random symval */
- }
- /* start a new rule and record its lhs. */
-
- ++nrules;
- ++nritems;
-
- p = symbol_list_new (lhs);
-
- crule1 = p1;
- if (p1)
- p1->next = p;
- else
- grammar = p;
-
- p1 = p;
- crule = p;
-
- /* mark the rule's lhs as a nonterminal if not already so. */
-
- if (lhs->class == unknown_sym)
- {
- lhs->class = nterm_sym;
- lhs->number = nvars;
- ++nvars;
- }
- else if (lhs->class == token_sym)
- complain (_("rule given for %s, which is a token"), lhs->tag);
-
- /* read the rhs of the rule. */
-
- for (;;)
- {
- t = lex ();
- if (t == tok_prec)
- {
- t = lex ();
- crule->ruleprec = symval;
- t = lex ();
- }
-
- if (!(t == tok_identifier || t == tok_left_curly))
- break;
-
- /* If next token is an identifier, see if a colon follows it.
- If one does, exit this rule now. */
- if (t == tok_identifier)
- {
- symbol_t *ssave;
- token_t t1;
-
- ssave = symval;
- t1 = lex ();
- unlex (t1);
- symval = ssave;
- if (t1 == tok_colon)
- {
- warn (_("previous rule lacks an ending `;'"));
- break;
- }
-
- if (!first_rhs) /* JF */
- first_rhs = symval;
- /* Not followed by colon =>
- process as part of this rule's rhs. */
- }
-
- /* If we just passed an action, that action was in the middle
- of a rule, so make a dummy rule to reduce it to a
- non-terminal. */
- if (action_flag)
- {
- /* Since the action was written out with this rule's
- number, we must give the new rule this number by
- inserting the new rule before it. */
-
- /* Make a dummy nonterminal, a gensym. */
- symbol_t *sdummy = gensym ();
-
- /* Make a new rule, whose body is empty, before the
- current one, so that the action just read can
- belong to it. */
- ++nrules;
- ++nritems;
- p = symbol_list_new (sdummy);
- /* Attach its lineno to that of the host rule. */
- p->line = crule->line;
- /* Move the action from the host rule to this one. */
- p->action = crule->action;
- p->action_line = crule->action_line;
- crule->action = NULL;
-
- if (crule1)
- crule1->next = p;
- else
- grammar = p;
- /* End of the rule. */
- crule1 = symbol_list_new (NULL);
- crule1->next = crule;
-
- p->next = crule1;
-
- /* Insert the dummy generated by that rule into this
- rule. */
- ++nritems;
- p = symbol_list_new (sdummy);
- p1->next = p;
- p1 = p;
-
- action_flag = 0;
- }
-
- if (t == tok_identifier)
- {
- ++nritems;
- p = symbol_list_new (symval);
- p1->next = p;
- p1 = p;
- }
- else /* handle an action. */
- {
- parse_action (crule, rulelength);
- action_flag = 1;
- ++xactions; /* JF */
- }
- ++rulelength;
- } /* end of read rhs of rule */
-
- /* Put an empty link in the list to mark the end of this rule */
- p = symbol_list_new (NULL);
- p1->next = p;
- p1 = p;
-
- if (t == tok_prec)
- {
- complain (_("two @prec's in a row"));
- t = lex ();
- crule->ruleprec = symval;
- t = lex ();
- }
-
- if (t == tok_left_curly)
- {
- /* This case never occurs -wjh */
- if (action_flag)
- complain (_("two actions at end of one rule"));
- parse_action (crule, rulelength);
- action_flag = 1;
- ++xactions; /* -wjh */
- t = lex ();
- }
- /* If $$ is being set in default way, report if any type
- mismatch. */
- else if (!xactions
- && first_rhs && lhs->type_name != first_rhs->type_name)
- {
- if (lhs->type_name == 0
- || first_rhs->type_name == 0
- || strcmp (lhs->type_name, first_rhs->type_name))
- complain (_("type clash (`%s' `%s') on default action"),
- lhs->type_name ? lhs->type_name : "",
- first_rhs->type_name ? first_rhs->type_name : "");
- }
- /* Warn if there is no default for $$ but we need one. */
- else if (!xactions && !first_rhs && lhs->type_name != 0)
- complain (_("empty rule for typed nonterminal, and no action"));
- if (t == tok_two_percents || t == tok_eof)
- warn (_("previous rule lacks an ending `;'"));
- if (t == tok_semicolon)
- t = lex ();
- }
- else
- {
- complain (_("invalid input: %s"), quote (token_buffer));
- t = lex ();
- }
-
- /* grammar has been read. Do some checking */
-
- if (nrules == 0)
- fatal (_("no rules in the input grammar"));
- /* Report any undefined symbols and consider them nonterminals. */
- symbols_check_defined ();
- /* Insert the initial rule, which line is that of the first rule
- (not that of the start symbol):
+/* Attach an ACTION to the current rule. If needed, move the previous
+ action as a mid-rule action. */
- axiom: %start EOF. */
- p = symbol_list_new (axiom);
- p->line = grammar->line;
- p->next = symbol_list_new (startsymbol);
- p->next->next = symbol_list_new (eoftoken);
- p->next->next->next = symbol_list_new (NULL);
- p->next->next->next->next = grammar;
- nrules += 1;
- nritems += 3;
- grammar = p;
-
- if (nsyms > SHRT_MAX)
- fatal (_("too many symbols (tokens plus nonterminals); maximum %d"),
- SHRT_MAX);
-
- assert (nsyms == ntokens + nvars);
-}
-
-/* At the end of the grammar file, some C source code must
- be stored. It is going to be associated to the epilogue
- directive. */
-static void
-read_additionnal_code (void)
+void
+grammar_current_rule_action_append (const char *action, location_t location)
{
- int c;
- struct obstack el_obstack;
-
- obstack_init (&el_obstack);
-
- if (!no_lines_flag)
- {
- obstack_fgrow2 (&el_obstack, muscle_find ("linef"),
- lineno, quotearg_style (c_quoting_style,
- muscle_find ("filename")));
- }
-
- while ((c = getc (finput)) != EOF)
- copy_character (&el_obstack, c);
-
- obstack_1grow (&el_obstack, 0);
- muscle_insert ("epilogue", obstack_finish (&el_obstack));
+ if (current_rule->action)
+ grammar_midrule_action ();
+ current_rule->action = action;
+ current_rule->action_location = location;
}
\f
{
unsigned int itemno;
int ruleno;
- symbol_list *p;
+ symbol_list_t *p;
ritem = XCALLOC (item_number_t, nritems);
rules = XCALLOC (rule_t, nrules) - 1;
rules[ruleno].number = ruleno;
rules[ruleno].lhs = p->sym;
rules[ruleno].rhs = ritem + itemno;
- rules[ruleno].line = p->line;
+ rules[ruleno].location = p->location;
rules[ruleno].useful = TRUE;
rules[ruleno].action = p->action;
- rules[ruleno].action_line = p->action_line;
+ rules[ruleno].action_location = p->action_location;
p = p->next;
while (p && p->sym)
void
reader (void)
{
- lex_init ();
+ gram_control_t gram_control;
lineno = 1;
- /* Initialize the muscle obstack. */
- obstack_init (&muscle_obstack);
-
/* Initialize the symbol table. */
symbols_new ();
/* Construct the axiom symbol. */
- axiom = getsym ("$axiom");
+ axiom = getsym ("$axiom", empty_location);
axiom->class = nterm_sym;
axiom->number = nvars++;
/* Construct the error token */
- errtoken = getsym ("error");
+ errtoken = getsym ("error", empty_location);
errtoken->class = token_sym;
errtoken->number = ntokens++;
/* Construct a token that represents all undefined literal tokens.
It is always token number 2. */
- undeftoken = getsym ("$undefined.");
+ undeftoken = getsym ("$undefined.", empty_location);
undeftoken->class = token_sym;
undeftoken->number = ntokens++;
/* Initialize the obstacks. */
- obstack_init (&action_obstack);
- obstack_init (&output_obstack);
obstack_init (&pre_prologue_obstack);
obstack_init (&post_prologue_obstack);
finput = xfopen (infile, "r");
+ gram_in = finput;
+
+ gram_debug = !!getenv ("parse");
+ gram__flex_debug = !!getenv ("scan");
+ scanner_initialize ();
+ gram_parse (&gram_control);
+
+ /* Grammar has been read. Do some checking */
+ if (nrules == 0)
+ fatal (_("no rules in the input grammar"));
- /* Read the declaration section. Copy %{ ... %} groups to
- TABLE_OBSTACK and FDEFINES file. Also notice any %token, %left,
- etc. found there. */
- read_declarations ();
+ /* Report any undefined symbols and consider them nonterminals. */
+ symbols_check_defined ();
/* If the user did not define her EOFTOKEN, do it now. */
if (!eoftoken)
{
- eoftoken = getsym ("$");
+ eoftoken = getsym ("$", empty_location);
eoftoken->class = token_sym;
eoftoken->number = 0;
/* Value specified by POSIX. */
eoftoken->user_token_number = 0;
}
- /* Read in the grammar, build grammar in list form. Write out
- actions. */
- readgram ();
- /* Some C code is given at the end of the grammar file. */
- read_additionnal_code ();
+ /* Insert the initial rule, which line is that of the first rule
+ (not that of the start symbol):
+
+ axiom: %start EOF. */
+ {
+ symbol_list_t *p = symbol_list_new (axiom, empty_location);
+ p->location = grammar->location;
+ p->next = symbol_list_new (startsymbol, empty_location);
+ p->next->next = symbol_list_new (eoftoken, empty_location);
+ p->next->next->next = symbol_list_new (NULL, empty_location);
+ p->next->next->next->next = grammar;
+ nrules += 1;
+ nritems += 3;
+ grammar = p;
+ }
+
+ if (nsyms > SHRT_MAX)
+ fatal (_("too many symbols (tokens plus nonterminals); maximum %d"),
+ SHRT_MAX);
+
+ assert (nsyms == ntokens + nvars);
- lex_free ();
xfclose (finput);
/* Assign the symbols their symbol numbers. Write #defines for the
/* Convert the grammar into the format described in gram.h. */
packgram ();
- /* The grammar as a symbol_list is no longer needed. */
- LIST_FREE (symbol_list, grammar);
+ /* The grammar as a symbol_list_t is no longer needed. */
+ LIST_FREE (symbol_list_t, grammar);
}
projects / bison.git / blobdiff