X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/2ce4ed68c9b156fd353ada1a986bb61dfa42f60a..7fe11bb55c1ca7e08f392b8bf413d18062019dd3:/src/scan-code.l
diff --git a/src/scan-code.l b/src/scan-code.l
index 4fc0664e..88f89902 100644
--- a/src/scan-code.l
+++ b/src/scan-code.l
@@ -1,12 +1,12 @@
/* Bison Action Scanner -*- C -*-
- Copyright (C) 2006 Free Software Foundation, Inc.
+ Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
- This program is free software; you can redistribute it and/or modify
+ 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; either version 2 of the License, or
+ the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
@@ -15,37 +15,32 @@
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
-*/
+ along with this program. If not, see . */
%option debug nodefault nounput noyywrap never-interactive
%option prefix="code_" outfile="lex.yy.c"
%{
-#include
-#include "system.h"
-
/* Work around a bug in flex 2.5.31. See Debian bug 333231
. */
#undef code_wrap
#define code_wrap() 1
#define FLEX_PREFIX(Id) code_ ## Id
-#include "complain.h"
-#include "flex-scanner.h"
-#include "reader.h"
-#include "getargs.h"
-#include
+#include
+
+#include
+#include
+#include
#include
#include
-
-#include "scan-code.h"
+#include
+#include
+#include
/* The current calling start condition: SC_RULE_ACTION or
SC_SYMBOL_ACTION. */
-# define YY_DECL char *code_lex (int sc_context, symbol_list *rule)
+# define YY_DECL static char *code_lex (code_props *self, int sc_context)
YY_DECL;
#define YY_USER_ACTION location_compute (loc, &loc->end, yytext, yyleng);
@@ -56,6 +51,9 @@ static void handle_action_at (symbol_list *rule, char *cp, location at_loc);
static location the_location;
static location *loc = &the_location;
+/* A string representing the most recent translation. */
+static char *last_string;
+
/* True if an untyped $$ or $n was seen. */
static bool untyped_var_seen;
%}
@@ -81,14 +79,27 @@ splice (\\[ \f\t\v]*\n)*
%{
/* Nesting level of the current code in braces. */
- int braces_level IF_LINT (= 0);
+ int braces_level = 0;
+
+ /* Whether a semicolon is probably needed.
+ The heuristic is that a semicolon is not needed after `{', `}', `;',
+ or a C preprocessor directive, and that whitespaces and comments
+ do not affect this flag.
+ Note that `{' does not need a semicolon because of `{}'.
+ A semicolon may be needed before a cpp direcive, but don't bother. */
+ bool need_semicolon = false;
+
+ /* Whether in a C preprocessor directive. Don't use a start condition
+ for this because, at the end of strings and comments, we still need
+ to know whether we're in a directive. */
+ bool in_cpp = false;
/* This scanner is special: it is invoked only once, henceforth
is expected to return only once. This initialization is
therefore done once per action to translate. */
- assert (sc_context == SC_SYMBOL_ACTION
- || sc_context == SC_RULE_ACTION
- || sc_context == INITIAL);
+ aver (sc_context == SC_SYMBOL_ACTION
+ || sc_context == SC_RULE_ACTION
+ || sc_context == INITIAL);
BEGIN sc_context;
%}
@@ -137,10 +148,12 @@ splice (\\[ \f\t\v]*\n)*
"'" {
STRING_GROW;
BEGIN SC_CHARACTER;
+ need_semicolon = true;
}
"\"" {
STRING_GROW;
BEGIN SC_STRING;
+ need_semicolon = true;
}
"/"{splice}"*" {
STRING_GROW;
@@ -154,47 +167,77 @@ splice (\\[ \f\t\v]*\n)*
{
- "$"("<"{tag}">")?(-?[0-9]+|"$") handle_action_dollar (rule, yytext, *loc);
- "@"(-?[0-9]+|"$") handle_action_at (rule, yytext, *loc);
+ "$"("<"{tag}">")?(-?[0-9]+|"$") {
+ handle_action_dollar (self->rule, yytext, *loc);
+ need_semicolon = true;
+ }
+ "@"(-?[0-9]+|"$") {
+ handle_action_at (self->rule, yytext, *loc);
+ need_semicolon = true;
+ }
"$" {
warn_at (*loc, _("stray `$'"));
obstack_sgrow (&obstack_for_string, "$][");
+ need_semicolon = true;
}
"@" {
warn_at (*loc, _("stray `@'"));
obstack_sgrow (&obstack_for_string, "@@");
+ need_semicolon = true;
+ }
+ "[" {
+ obstack_sgrow (&obstack_for_string, "@{");
+ need_semicolon = true;
+ }
+ "]" {
+ obstack_sgrow (&obstack_for_string, "@}");
+ need_semicolon = true;
}
- "{" STRING_GROW; ++braces_level;
+ ";" STRING_GROW; need_semicolon = false;
+ "{" STRING_GROW; ++braces_level; need_semicolon = false;
"}" {
- bool outer_brace = --braces_level < 0;
+ bool outer_brace = --braces_level == 0;
/* As an undocumented Bison extension, append `;' before the last
brace in braced code, so that the user code can omit trailing
`;'. But do not append `;' if emulating Yacc, since Yacc does
- not append one.
-
- FIXME: Bison should warn if a semicolon seems to be necessary
- here, and should omit the semicolon if it seems unnecessary
- (e.g., after ';', '{', or '}', each followed by comments or
- white space). Such a warning shouldn't depend on --yacc; it
- should depend on a new --pedantic option, which would cause
- Bison to warn if it detects an extension to POSIX. --pedantic
- should also diagnose other Bison extensions like %yacc.
- Perhaps there should also be a GCC-style --pedantic-errors
- option, so that such warnings are diagnosed as errors. */
- if (outer_brace && ! yacc_flag)
- obstack_1grow (&obstack_for_string, ';');
+ not append one. */
+ if (outer_brace && !yacc_flag && language_prio == default_prio
+ && skeleton_prio == default_prio && need_semicolon && ! in_cpp)
+ {
+ warn_at (*loc, _("a `;' might be needed at the end of action code"));
+ warn_at (*loc, _("future versions of Bison will not add the `;'"));
+ obstack_1grow (&obstack_for_string, ';');
+ }
STRING_GROW;
+ need_semicolon = false;
}
+
+ /* Preprocessing directives should only be recognized at the beginning
+ of lines, allowing whitespace including comments, but in C/C++,
+ `#' can only be the start of preprocessor directives or within
+ `#define' directives anyway, so don't bother with begin of line. */
+ "#" STRING_GROW; in_cpp = true;
+
+ {splice} STRING_GROW;
+ [\n\r] STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false;
+ [ \t\f] STRING_GROW;
+ . STRING_GROW; need_semicolon = true;
}
{
- "$$" obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
- "@$" obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
+ "$$" {
+ obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
+ self->is_value_used = true;
+ }
+ "@$" {
+ obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
+ muscle_percent_define_ensure("locations", the_location, true);
+ }
}
@@ -218,8 +261,8 @@ splice (\\[ \f\t\v]*\n)*
/* End of processing. */
<*><> {
- obstack_1grow (&obstack_for_string, '\0');
- return obstack_finish (&obstack_for_string);
+ STRING_FINISH;
+ return last_string;
}
%%
@@ -241,7 +284,7 @@ int max_left_semantic_context = 0;
static void
handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
{
- const char *type_name = NULL;
+ char const *type_name = NULL;
char *cp = text + 1;
symbol_list *effective_rule;
int effective_rule_length;
@@ -284,10 +327,10 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
_("$$ for the midrule at $%d of `%s'"
" has no declared type"),
rule->midrule_parent_rhs_index,
- effective_rule->sym->tag);
+ effective_rule->content.sym->tag);
else
complain_at (dollar_loc, _("$$ of `%s' has no declared type"),
- rule->sym->tag);
+ rule->content.sym->tag);
}
else
untyped_var_seen = true;
@@ -296,7 +339,7 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
obstack_fgrow1 (&obstack_for_string,
"]b4_lhs_value([%s])[", type_name);
- rule->used = true;
+ rule->action_props.is_value_used = true;
}
else
{
@@ -315,7 +358,7 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
{
if (union_seen | tag_seen)
complain_at (dollar_loc, _("$%d of `%s' has no declared type"),
- n, effective_rule->sym->tag);
+ n, effective_rule->content.sym->tag);
else
untyped_var_seen = true;
type_name = "";
@@ -324,7 +367,9 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
obstack_fgrow3 (&obstack_for_string,
"]b4_rhs_value(%d, %d, [%s])[",
effective_rule_length, n, type_name);
- symbol_list_n_used_set (effective_rule, n, true);
+ if (n > 0)
+ symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
+ true;
}
else
complain_at (dollar_loc, _("integer out of range: %s"), quote (text));
@@ -341,13 +386,12 @@ static void
handle_action_at (symbol_list *rule, char *text, location at_loc)
{
char *cp = text + 1;
- locations_flag = true;
- int effective_rule_length;
+ int effective_rule_length =
+ (rule->midrule_parent_rule
+ ? rule->midrule_parent_rhs_index - 1
+ : symbol_list_length (rule->next));
- if (rule->midrule_parent_rule)
- effective_rule_length = rule->midrule_parent_rhs_index - 1;
- else
- effective_rule_length = symbol_list_length (rule->next);
+ muscle_percent_define_ensure("locations", at_loc, true);
if (*cp == '$')
obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
@@ -372,59 +416,102 @@ handle_action_at (symbol_list *rule, char *text, location at_loc)
| Initialize the scanner. |
`-------------------------*/
-/* Translate the dollars and ats in \a a, whose location is \a l. The
- translation is for \a rule, in the context \a sc_context
+/* Translate the dollars and ats in \a self, in the context \a sc_context
(SC_RULE_ACTION, SC_SYMBOL_ACTION, INITIAL). */
-static char *
-translate_action (int sc_context, symbol_list *rule, const char *a, location l)
+static char const *
+translate_action (code_props *self, int sc_context)
{
char *res;
static bool initialized = false;
if (!initialized)
{
obstack_init (&obstack_for_string);
- /* The initial buffer, never used. */
- yy_delete_buffer (YY_CURRENT_BUFFER);
yy_flex_debug = 0;
initialized = true;
}
- loc->start = loc->end = l.start;
- yy_switch_to_buffer (yy_scan_string (a));
- res = code_lex (sc_context, rule);
+ loc->start = loc->end = self->location.start;
+ yy_switch_to_buffer (yy_scan_string (self->code));
+ res = code_lex (self, sc_context);
yy_delete_buffer (YY_CURRENT_BUFFER);
return res;
}
-char *
-translate_rule_action (symbol_list *rule)
+/*------------------------------------------------------------------------.
+| Implementation of the public interface as documented in "scan-code.h". |
+`------------------------------------------------------------------------*/
+
+void
+code_props_none_init (code_props *self)
+{
+ *self = code_props_none;
+}
+
+code_props const code_props_none = CODE_PROPS_NONE_INIT;
+
+void
+code_props_plain_init (code_props *self, char const *code, location code_loc)
+{
+ self->kind = CODE_PROPS_PLAIN;
+ self->code = code;
+ self->location = code_loc;
+ self->is_value_used = false;
+ self->rule = NULL;
+}
+
+void
+code_props_symbol_action_init (code_props *self, char const *code,
+ location code_loc)
{
- return translate_action (SC_RULE_ACTION, rule, rule->action,
- rule->action_location);
+ self->kind = CODE_PROPS_SYMBOL_ACTION;
+ self->code = code;
+ self->location = code_loc;
+ self->is_value_used = false;
+ self->rule = NULL;
}
-char *
-translate_symbol_action (const char *a, location l)
+void
+code_props_rule_action_init (code_props *self, char const *code,
+ location code_loc, symbol_list *rule)
{
- return translate_action (SC_SYMBOL_ACTION, NULL, a, l);
+ self->kind = CODE_PROPS_RULE_ACTION;
+ self->code = code;
+ self->location = code_loc;
+ self->is_value_used = false;
+ self->rule = rule;
}
-char *
-translate_code (const char *a, location l)
+void
+code_props_translate_code (code_props *self)
{
- return translate_action (INITIAL, NULL, a, l);
+ switch (self->kind)
+ {
+ case CODE_PROPS_NONE:
+ break;
+ case CODE_PROPS_PLAIN:
+ self->code = translate_action (self, INITIAL);
+ break;
+ case CODE_PROPS_SYMBOL_ACTION:
+ self->code = translate_action (self, SC_SYMBOL_ACTION);
+ break;
+ case CODE_PROPS_RULE_ACTION:
+ self->code = translate_action (self, SC_RULE_ACTION);
+ break;
+ }
}
-/*-----------------------------------------------.
-| Free all the memory allocated to the scanner. |
-`-----------------------------------------------*/
+void
+code_scanner_last_string_free (void)
+{
+ STRING_FREE;
+}
void
code_scanner_free (void)
{
obstack_free (&obstack_for_string, 0);
/* Reclaim Flex's buffers. */
- yy_delete_buffer (YY_CURRENT_BUFFER);
+ yylex_destroy ();
}