src/scan-code.l

/* Bison Action Scanner                             -*- C -*-

   Copyright (C) 2006, 2007, 2008 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
   it under the terms of the GNU General Public License as published by
   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,
   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, see <http://www.gnu.org/licenses/>.  */

%option debug nodefault nounput noyywrap never-interactive
%option prefix="code_" outfile="lex.yy.c"

%{
/* Work around a bug in flex 2.5.31.  See Debian bug 333231
   <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
#undef code_wrap
#define code_wrap() 1

#define FLEX_PREFIX(Id) code_ ## Id
#include <src/flex-scanner.h>

#include <src/complain.h>
#include <src/reader.h>
#include <src/getargs.h>
#include <get-errno.h>
#include <quote.h>

#include <src/scan-code.h>
#include <src/symlist.h>

/* The current calling start condition: SC_RULE_ACTION or
   SC_SYMBOL_ACTION. */
# 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);

static void handle_action_dollar (symbol_list *rule, char *cp,
				  location dollar_loc);
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;
%}
 /* C and C++ comments in code. */
%x SC_COMMENT SC_LINE_COMMENT
 /* Strings and characters in code. */
%x SC_STRING SC_CHARACTER
 /* Whether in a rule or symbol action.  Specifies the translation
    of $ and @.  */
%x SC_RULE_ACTION SC_SYMBOL_ACTION


/* POSIX says that a tag must be both an id and a C union member, but
   historically almost any character is allowed in a tag.  We disallow
   NUL and newline, as this simplifies our implementation.  */
tag	 [^\0\n>]+

/* Zero or more instances of backslash-newline.  Following GCC, allow
   white space between the backslash and the newline.  */
splice	 (\\[ \f\t\v]*\n)*

%%

%{
  /* Nesting level of the current code in braces.  */
  int braces_level = 0;

  /* 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. */
  aver (sc_context == SC_SYMBOL_ACTION
	|| sc_context == SC_RULE_ACTION
	|| sc_context == INITIAL);
  BEGIN sc_context;
%}

  /*------------------------------------------------------------.
  | Scanning a C comment.  The initial `/ *' is already eaten.  |
  `------------------------------------------------------------*/

<SC_COMMENT>
{
  "*"{splice}"/"  STRING_GROW; BEGIN sc_context;
}


  /*--------------------------------------------------------------.
  | Scanning a line comment.  The initial `//' is already eaten.  |
  `--------------------------------------------------------------*/

<SC_LINE_COMMENT>
{
  "\n"		 STRING_GROW; BEGIN sc_context;
  {splice}	 STRING_GROW;
}


  /*--------------------------------------------.
  | Scanning user-code characters and strings.  |
  `--------------------------------------------*/

<SC_CHARACTER,SC_STRING>
{
  {splice}|\\{splice}.	STRING_GROW;
}

<SC_CHARACTER>
{
  "'"		STRING_GROW; BEGIN sc_context;
}

<SC_STRING>
{
  "\""		STRING_GROW; BEGIN sc_context;
}


<SC_RULE_ACTION,SC_SYMBOL_ACTION>{
  "'" {
    STRING_GROW;
    BEGIN SC_CHARACTER;
  }
  "\"" {
    STRING_GROW;
    BEGIN SC_STRING;
  }
  "/"{splice}"*" {
    STRING_GROW;
    BEGIN SC_COMMENT;
  }
  "/"{splice}"/" {
    STRING_GROW;
    BEGIN SC_LINE_COMMENT;
  }
}

<SC_RULE_ACTION>
{
  "$"("<"{tag}">")?(-?[0-9]+|"$")  {
    handle_action_dollar (self->rule, yytext, *loc);
  }
  "@"(-?[0-9]+|"$") {
    handle_action_at (self->rule, yytext, *loc);
  }

  "$"  {
    warn_at (*loc, _("stray `$'"));
    obstack_sgrow (&obstack_for_string, "$][");
  }
  "@"  {
    warn_at (*loc, _("stray `@'"));
    obstack_sgrow (&obstack_for_string, "@@");
  }

  "{"  STRING_GROW; ++braces_level;
  "}"  {
    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.  Also, some output languages (like Java) do not
       accept an extra semicolon, so don't append if the user specified
       a skeleton or language.

       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 && language_prio == default_prio
        && skeleton_prio == default_prio)
      obstack_1grow (&obstack_for_string, ';');

    STRING_GROW;
  }
}

<SC_SYMBOL_ACTION>
{
  "$$" {
    obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
    self->is_value_used = true;
  }
  "@$" {
    obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
    locations_flag = true;
  }
}


  /*-----------------------------------------.
  | Escape M4 quoting characters in C code.  |
  `-----------------------------------------*/

<*>
{
  \$	obstack_sgrow (&obstack_for_string, "$][");
  \@	obstack_sgrow (&obstack_for_string, "@@");
  \[	obstack_sgrow (&obstack_for_string, "@{");
  \]	obstack_sgrow (&obstack_for_string, "@}");
}

  /*-----------------------------------------------------.
  | By default, grow the string obstack with the input.  |
  `-----------------------------------------------------*/

<*>.|\n	STRING_GROW;

 /* End of processing. */
<*><<EOF>>	 {
                   STRING_FINISH;
                   return last_string;
                 }

%%

/* Keeps track of the maximum number of semantic values to the left of
   a handle (those referenced by $0, $-1, etc.) are required by the
   semantic actions of this grammar. */
int max_left_semantic_context = 0;


/*------------------------------------------------------------------.
| TEXT is pointing to a wannabee semantic value (i.e., a `$').      |
|                                                                   |
| Possible inputs: $[<TYPENAME>]($|integer)                         |
|                                                                   |
| Output to OBSTACK_FOR_STRING a reference to this semantic value.  |
`------------------------------------------------------------------*/

static void
handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
{
  char const *type_name = NULL;
  char *cp = text + 1;
  symbol_list *effective_rule;
  int effective_rule_length;

  if (rule->midrule_parent_rule)
    {
      effective_rule = rule->midrule_parent_rule;
      effective_rule_length = rule->midrule_parent_rhs_index - 1;
    }
  else
    {
      effective_rule = rule;
      effective_rule_length = symbol_list_length (rule->next);
    }

  /* Get the type name if explicit. */
  if (*cp == '<')
    {
      type_name = ++cp;
      while (*cp != '>')
	++cp;
      *cp = '\0';
      ++cp;
      if (untyped_var_seen)
	complain_at (dollar_loc, _("explicit type given in untyped grammar"));
      tag_seen = true;
    }

  if (*cp == '$')
    {
      if (!type_name)
	type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0);

      if (!type_name)
	{
	  if (union_seen | tag_seen)
	    {
	      if (rule->midrule_parent_rule)
		complain_at (dollar_loc,
			     _("$$ for the midrule at $%d of `%s'"
			       " has no declared type"),
			     rule->midrule_parent_rhs_index,
			     effective_rule->content.sym->tag);
	      else
		complain_at (dollar_loc, _("$$ of `%s' has no declared type"),
			     rule->content.sym->tag);
	    }
	  else
	    untyped_var_seen = true;
	  type_name = "";
	}

      obstack_fgrow1 (&obstack_for_string,
		      "]b4_lhs_value([%s])[", type_name);
      rule->action_props.is_value_used = true;
    }
  else
    {
      long int num = strtol (cp, NULL, 10);

      if (1 - INT_MAX + effective_rule_length <= num
	  && num <= effective_rule_length)
	{
	  int n = num;
	  if (max_left_semantic_context < 1 - n)
	    max_left_semantic_context = 1 - n;
	  if (!type_name && 0 < n)
	    type_name =
	      symbol_list_n_type_name_get (effective_rule, dollar_loc, n);
	  if (!type_name)
	    {
	      if (union_seen | tag_seen)
		complain_at (dollar_loc, _("$%d of `%s' has no declared type"),
			     n, effective_rule->content.sym->tag);
	      else
		untyped_var_seen = true;
	      type_name = "";
	    }

	  obstack_fgrow3 (&obstack_for_string,
			  "]b4_rhs_value(%d, %d, [%s])[",
			  effective_rule_length, n, type_name);
          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));
    }
}


/*------------------------------------------------------.
| TEXT is a location token (i.e., a `@...').  Output to |
| OBSTACK_FOR_STRING a reference to this location.      |
`------------------------------------------------------*/

static void
handle_action_at (symbol_list *rule, char *text, location at_loc)
{
  char *cp = text + 1;
  int effective_rule_length =
    (rule->midrule_parent_rule
     ? rule->midrule_parent_rhs_index - 1
     : symbol_list_length (rule->next));

  locations_flag = true;

  if (*cp == '$')
    obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
  else
    {
      long int num = strtol (cp, NULL, 10);

      if (1 - INT_MAX + effective_rule_length <= num
	  && num <= effective_rule_length)
	{
	  int n = num;
	  obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",
			  effective_rule_length, n);
	}
      else
	complain_at (at_loc, _("integer out of range: %s"), quote (text));
    }
}


/*-------------------------.
| Initialize the scanner.  |
`-------------------------*/

/* Translate the dollars and ats in \a self, in the context \a sc_context
   (SC_RULE_ACTION, SC_SYMBOL_ACTION, INITIAL).  */

static char const *
translate_action (code_props *self, int sc_context)
{
  char *res;
  static bool initialized = false;
  if (!initialized)
    {
      obstack_init (&obstack_for_string);
      yy_flex_debug = 0;
      initialized = true;
    }

  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;
}

/*------------------------------------------------------------------------.
| 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)
{
  self->kind = CODE_PROPS_SYMBOL_ACTION;
  self->code = code;
  self->location = code_loc;
  self->is_value_used = false;
  self->rule = NULL;
}

void
code_props_rule_action_init (code_props *self, char const *code,
                             location code_loc, symbol_list *rule)
{
  self->kind = CODE_PROPS_RULE_ACTION;
  self->code = code;
  self->location = code_loc;
  self->is_value_used = false;
  self->rule = rule;
}

void
code_props_translate_code (code_props *self)
{
  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;
    }
}

void
code_scanner_last_string_free (void)
{
  STRING_FREE;
}

void
code_scanner_free (void)
{
  obstack_free (&obstack_for_string, 0);
  /* Reclaim Flex's buffers.  */
  yylex_destroy ();
}
Commit	Line	Data
	1	/* Bison Action Scanner -- C --
	2
	3	Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
	4
	5	This file is part of Bison, the GNU Compiler Compiler.
	6
	7	This program is free software: you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation, either version 3 of the License, or
	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program. If not, see <http://www.gnu.org/licenses/>. */
	19
	20	%option debug nodefault nounput noyywrap never-interactive
	21	%option prefix="code_" outfile="lex.yy.c"
	22
	23	%{
	24	/* Work around a bug in flex 2.5.31. See Debian bug 333231
	25	<http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>. */
	26	#undef code_wrap
	27	#define code_wrap() 1
	28
	29	#define FLEX_PREFIX(Id) code_ ## Id
	30	#include <src/flex-scanner.h>
	31
	32	#include <src/complain.h>
	33	#include <src/reader.h>
	34	#include <src/getargs.h>
	35	#include <get-errno.h>
	36	#include <quote.h>
	37
	38	#include <src/scan-code.h>
	39	#include <src/symlist.h>
	40
	41	/* The current calling start condition: SC_RULE_ACTION or
	42	SC_SYMBOL_ACTION. */
	43	# define YY_DECL static char code_lex (code_props self, int sc_context)
	44	YY_DECL;
	45
	46	#define YY_USER_ACTION location_compute (loc, &loc->end, yytext, yyleng);
	47
	48	static void handle_action_dollar (symbol_list rule, char cp,
	49	location dollar_loc);
	50	static void handle_action_at (symbol_list rule, char cp, location at_loc);
	51	static location the_location;
	52	static location *loc = &the_location;
	53
	54	/* A string representing the most recent translation. */
	55	static char *last_string;
	56
	57	/* True if an untyped $$ or $n was seen. */
	58	static bool untyped_var_seen;
	59	%}
	60	/* C and C++ comments in code. */
	61	%x SC_COMMENT SC_LINE_COMMENT
	62	/* Strings and characters in code. */
	63	%x SC_STRING SC_CHARACTER
	64	/* Whether in a rule or symbol action. Specifies the translation
	65	of $ and @. */
	66	%x SC_RULE_ACTION SC_SYMBOL_ACTION
	67
	68
	69	/* POSIX says that a tag must be both an id and a C union member, but
	70	historically almost any character is allowed in a tag. We disallow
	71	NUL and newline, as this simplifies our implementation. */
	72	tag [^\0\n>]+
	73
	74	/* Zero or more instances of backslash-newline. Following GCC, allow
	75	white space between the backslash and the newline. */
	76	splice (\\[ \f\t\v]\n)
	77
	78	%%
	79
	80	%{
	81	/* Nesting level of the current code in braces. */
	82	int braces_level = 0;
	83
	84	/* This scanner is special: it is invoked only once, henceforth
	85	is expected to return only once. This initialization is
	86	therefore done once per action to translate. */
	87	aver (sc_context == SC_SYMBOL_ACTION
	88	\|\| sc_context == SC_RULE_ACTION
	89	\|\| sc_context == INITIAL);
	90	BEGIN sc_context;
	91	%}
	92
	93	/*------------------------------------------------------------.
	94	\| Scanning a C comment. The initial `/ *' is already eaten. \|
	95	`------------------------------------------------------------*/
	96
	97	<SC_COMMENT>
	98	{
	99	"*"{splice}"/" STRING_GROW; BEGIN sc_context;
	100	}
	101
	102
	103	/*--------------------------------------------------------------.
	104	\| Scanning a line comment. The initial `//' is already eaten. \|
	105	`--------------------------------------------------------------*/
	106
	107	<SC_LINE_COMMENT>
	108	{
	109	"\n" STRING_GROW; BEGIN sc_context;
	110	{splice} STRING_GROW;
	111	}
	112
	113
	114	/*--------------------------------------------.
	115	\| Scanning user-code characters and strings. \|
	116	`--------------------------------------------*/
	117
	118	<SC_CHARACTER,SC_STRING>
	119	{
	120	{splice}\|\\{splice}. STRING_GROW;
	121	}
	122
	123	<SC_CHARACTER>
	124	{
	125	"'" STRING_GROW; BEGIN sc_context;
	126	}
	127
	128	<SC_STRING>
	129	{
	130	"\"" STRING_GROW; BEGIN sc_context;
	131	}
	132
	133
	134	<SC_RULE_ACTION,SC_SYMBOL_ACTION>{
	135	"'" {
	136	STRING_GROW;
	137	BEGIN SC_CHARACTER;
	138	}
	139	"\"" {
	140	STRING_GROW;
	141	BEGIN SC_STRING;
	142	}
	143	"/"{splice}"*" {
	144	STRING_GROW;
	145	BEGIN SC_COMMENT;
	146	}
	147	"/"{splice}"/" {
	148	STRING_GROW;
	149	BEGIN SC_LINE_COMMENT;
	150	}
	151	}
	152
	153	<SC_RULE_ACTION>
	154	{
	155	"$"("<"{tag}">")?(-?[0-9]+\|"$") {
	156	handle_action_dollar (self->rule, yytext, *loc);
	157	}
	158	"@"(-?[0-9]+\|"$") {
	159	handle_action_at (self->rule, yytext, *loc);
	160	}
	161
	162	"$" {
	163	warn_at (*loc, _("stray `$'"));
	164	obstack_sgrow (&obstack_for_string, "$][");
	165	}
	166	"@" {
	167	warn_at (*loc, _("stray `@'"));
	168	obstack_sgrow (&obstack_for_string, "@@");
	169	}
	170
	171	"{" STRING_GROW; ++braces_level;
	172	"}" {
	173	bool outer_brace = --braces_level == 0;
	174
	175	/* As an undocumented Bison extension, append `;' before the last
	176	brace in braced code, so that the user code can omit trailing
	177	`;'. But do not append `;' if emulating Yacc, since Yacc does
	178	not append one. Also, some output languages (like Java) do not
	179	accept an extra semicolon, so don't append if the user specified
	180	a skeleton or language.
	181
	182	FIXME: Bison should warn if a semicolon seems to be necessary
	183	here, and should omit the semicolon if it seems unnecessary
	184	(e.g., after ';', '{', or '}', each followed by comments or
	185	white space). Such a warning shouldn't depend on --yacc; it
	186	should depend on a new --pedantic option, which would cause
	187	Bison to warn if it detects an extension to POSIX. --pedantic
	188	should also diagnose other Bison extensions like %yacc.
	189	Perhaps there should also be a GCC-style --pedantic-errors
	190	option, so that such warnings are diagnosed as errors. */
	191	if (outer_brace && !yacc_flag && language_prio == default_prio
	192	&& skeleton_prio == default_prio)
	193	obstack_1grow (&obstack_for_string, ';');
	194
	195	STRING_GROW;
	196	}
	197	}
	198
	199	<SC_SYMBOL_ACTION>
	200	{
	201	"$$" {
	202	obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
	203	self->is_value_used = true;
	204	}
	205	"@$" {
	206	obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
	207	locations_flag = true;
	208	}
	209	}
	210
	211
	212	/*-----------------------------------------.
	213	\| Escape M4 quoting characters in C code. \|
	214	`-----------------------------------------*/
	215
	216	<*>
	217	{
	218	\$ obstack_sgrow (&obstack_for_string, "$][");
	219	\@ obstack_sgrow (&obstack_for_string, "@@");
	220	\[ obstack_sgrow (&obstack_for_string, "@{");
	221	\] obstack_sgrow (&obstack_for_string, "@}");
	222	}
	223
	224	/*-----------------------------------------------------.
	225	\| By default, grow the string obstack with the input. \|
	226	`-----------------------------------------------------*/
	227
	228	<*>.\|\n STRING_GROW;
	229
	230	/* End of processing. */
	231	<*><<EOF>> {
	232	STRING_FINISH;
	233	return last_string;
	234	}
	235
	236	%%
	237
	238	/* Keeps track of the maximum number of semantic values to the left of
	239	a handle (those referenced by $0, $-1, etc.) are required by the
	240	semantic actions of this grammar. */
	241	int max_left_semantic_context = 0;
	242
	243
	244	/*------------------------------------------------------------------.
	245	\| TEXT is pointing to a wannabee semantic value (i.e., a `$'). \|
	246	\| \|
	247	\| Possible inputs: $[<TYPENAME>]($\|integer) \|
	248	\| \|
	249	\| Output to OBSTACK_FOR_STRING a reference to this semantic value. \|
	250	`------------------------------------------------------------------*/
	251
	252	static void
	253	handle_action_dollar (symbol_list rule, char text, location dollar_loc)
	254	{
	255	char const *type_name = NULL;
	256	char *cp = text + 1;
	257	symbol_list *effective_rule;
	258	int effective_rule_length;
	259
	260	if (rule->midrule_parent_rule)
	261	{
	262	effective_rule = rule->midrule_parent_rule;
	263	effective_rule_length = rule->midrule_parent_rhs_index - 1;
	264	}
	265	else
	266	{
	267	effective_rule = rule;
	268	effective_rule_length = symbol_list_length (rule->next);
	269	}
	270
	271	/* Get the type name if explicit. */
	272	if (*cp == '<')
	273	{
	274	type_name = ++cp;
	275	while (*cp != '>')
	276	++cp;
	277	*cp = '\0';
	278	++cp;
	279	if (untyped_var_seen)
	280	complain_at (dollar_loc, _("explicit type given in untyped grammar"));
	281	tag_seen = true;
	282	}
	283
	284	if (*cp == '$')
	285	{
	286	if (!type_name)
	287	type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0);
	288
	289	if (!type_name)
	290	{
	291	if (union_seen \| tag_seen)
	292	{
	293	if (rule->midrule_parent_rule)
	294	complain_at (dollar_loc,
	295	_("$$ for the midrule at $%d of `%s'"
	296	" has no declared type"),
	297	rule->midrule_parent_rhs_index,
	298	effective_rule->content.sym->tag);
	299	else
	300	complain_at (dollar_loc, _("$$ of `%s' has no declared type"),
	301	rule->content.sym->tag);
	302	}
	303	else
	304	untyped_var_seen = true;
	305	type_name = "";
	306	}
	307
	308	obstack_fgrow1 (&obstack_for_string,
	309	"]b4_lhs_value([%s])[", type_name);
	310	rule->action_props.is_value_used = true;
	311	}
	312	else
	313	{
	314	long int num = strtol (cp, NULL, 10);
	315
	316	if (1 - INT_MAX + effective_rule_length <= num
	317	&& num <= effective_rule_length)
	318	{
	319	int n = num;
	320	if (max_left_semantic_context < 1 - n)
	321	max_left_semantic_context = 1 - n;
	322	if (!type_name && 0 < n)
	323	type_name =
	324	symbol_list_n_type_name_get (effective_rule, dollar_loc, n);
	325	if (!type_name)
	326	{
	327	if (union_seen \| tag_seen)
	328	complain_at (dollar_loc, _("$%d of `%s' has no declared type"),
	329	n, effective_rule->content.sym->tag);
	330	else
	331	untyped_var_seen = true;
	332	type_name = "";
	333	}
	334
	335	obstack_fgrow3 (&obstack_for_string,
	336	"]b4_rhs_value(%d, %d, [%s])[",
	337	effective_rule_length, n, type_name);
	338	if (n > 0)
	339	symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
	340	true;
	341	}
	342	else
	343	complain_at (dollar_loc, _("integer out of range: %s"), quote (text));
	344	}
	345	}
	346
	347
	348	/*------------------------------------------------------.
	349	\| TEXT is a location token (i.e., a `@...'). Output to \|
	350	\| OBSTACK_FOR_STRING a reference to this location. \|
	351	`------------------------------------------------------*/
	352
	353	static void
	354	handle_action_at (symbol_list rule, char text, location at_loc)
	355	{
	356	char *cp = text + 1;
	357	int effective_rule_length =
	358	(rule->midrule_parent_rule
	359	? rule->midrule_parent_rhs_index - 1
	360	: symbol_list_length (rule->next));
	361
	362	locations_flag = true;
	363
	364	if (*cp == '$')
	365	obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
	366	else
	367	{
	368	long int num = strtol (cp, NULL, 10);
	369
	370	if (1 - INT_MAX + effective_rule_length <= num
	371	&& num <= effective_rule_length)
	372	{
	373	int n = num;
	374	obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",
	375	effective_rule_length, n);
	376	}
	377	else
	378	complain_at (at_loc, _("integer out of range: %s"), quote (text));
	379	}
	380	}
	381
	382
	383	/*-------------------------.
	384	\| Initialize the scanner. \|
	385	`-------------------------*/
	386
	387	/* Translate the dollars and ats in \a self, in the context \a sc_context
	388	(SC_RULE_ACTION, SC_SYMBOL_ACTION, INITIAL). */
	389
	390	static char const *
	391	translate_action (code_props *self, int sc_context)
	392	{
	393	char *res;
	394	static bool initialized = false;
	395	if (!initialized)
	396	{
	397	obstack_init (&obstack_for_string);
	398	yy_flex_debug = 0;
	399	initialized = true;
	400	}
	401
	402	loc->start = loc->end = self->location.start;
	403	yy_switch_to_buffer (yy_scan_string (self->code));
	404	res = code_lex (self, sc_context);
	405	yy_delete_buffer (YY_CURRENT_BUFFER);
	406
	407	return res;
	408	}
	409
	410	/*------------------------------------------------------------------------.
	411	\| Implementation of the public interface as documented in "scan-code.h". \|
	412	`------------------------------------------------------------------------*/
	413
	414	void
	415	code_props_none_init (code_props *self)
	416	{
	417	*self = code_props_none;
	418	}
	419
	420	code_props const code_props_none = CODE_PROPS_NONE_INIT;
	421
	422	void
	423	code_props_plain_init (code_props self, char const code, location code_loc)
	424	{
	425	self->kind = CODE_PROPS_PLAIN;
	426	self->code = code;
	427	self->location = code_loc;
	428	self->is_value_used = false;
	429	self->rule = NULL;
	430	}
	431
	432	void
	433	code_props_symbol_action_init (code_props self, char const code,
	434	location code_loc)
	435	{
	436	self->kind = CODE_PROPS_SYMBOL_ACTION;
	437	self->code = code;
	438	self->location = code_loc;
	439	self->is_value_used = false;
	440	self->rule = NULL;
	441	}
	442
	443	void
	444	code_props_rule_action_init (code_props self, char const code,
	445	location code_loc, symbol_list *rule)
	446	{
	447	self->kind = CODE_PROPS_RULE_ACTION;
	448	self->code = code;
	449	self->location = code_loc;
	450	self->is_value_used = false;
	451	self->rule = rule;
	452	}
	453
	454	void
	455	code_props_translate_code (code_props *self)
	456	{
	457	switch (self->kind)
	458	{
	459	case CODE_PROPS_NONE:
	460	break;
	461	case CODE_PROPS_PLAIN:
	462	self->code = translate_action (self, INITIAL);
	463	break;
	464	case CODE_PROPS_SYMBOL_ACTION:
	465	self->code = translate_action (self, SC_SYMBOL_ACTION);
	466	break;
	467	case CODE_PROPS_RULE_ACTION:
	468	self->code = translate_action (self, SC_RULE_ACTION);
	469	break;
	470	}
	471	}
	472
	473	void
	474	code_scanner_last_string_free (void)
	475	{
	476	STRING_FREE;
	477	}
	478
	479	void
	480	code_scanner_free (void)
	481	{
	482	obstack_free (&obstack_for_string, 0);
	483	/* Reclaim Flex's buffers. */
	484	yylex_destroy ();
	485	}