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bison/src/scan-gram.l

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/* Bison Grammar Scanner -*- C -*-
Copyright (C) 2002, 2003 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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA
*/
%option debug nodefault noyywrap never-interactive
%option prefix="gram_" outfile="lex.yy.c"
%{
#include "system.h"
#include <mbswidth.h>
#include <get-errno.h>
#include <quote.h>
#include "complain.h"
#include "files.h"
#include "getargs.h"
#include "gram.h"
#include "reader.h"
#include "uniqstr.h"
#define YY_USER_INIT \
do \
{ \
scanner_cursor.file = current_file; \
scanner_cursor.line = 1; \
scanner_cursor.column = 1; \
} \
while (0)
/* Location of scanner cursor. */
boundary scanner_cursor;
static void adjust_location (location *, char const *, size_t);
#define YY_USER_ACTION adjust_location (loc, yytext, yyleng);
static size_t no_cr_read (FILE *, char *, size_t);
#define YY_INPUT(buf, result, size) ((result) = no_cr_read (yyin, buf, size))
/* OBSTACK_FOR_STRING -- Used to store all the characters that we need to
keep (to construct ID, STRINGS etc.). Use the following macros to
use it.
Use STRING_GROW to append what has just been matched, and
STRING_FINISH to end the string (it puts the ending 0).
STRING_FINISH also stores this string in LAST_STRING, which can be
used, and which is used by STRING_FREE to free the last string. */
static struct obstack obstack_for_string;
/* A string representing the most recently saved token. */
static char *last_string;
#define STRING_GROW \
obstack_grow (&obstack_for_string, yytext, yyleng)
#define STRING_FINISH \
do { \
obstack_1grow (&obstack_for_string, '\0'); \
last_string = obstack_finish (&obstack_for_string); \
} while (0)
#define STRING_FREE \
obstack_free (&obstack_for_string, last_string)
void
scanner_last_string_free (void)
{
STRING_FREE;
}
/* Within well-formed rules, 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.
Outside of well-formed rules, RULE_LENGTH has an undefined value. */
static int rule_length;
static void handle_dollar (int token_type, char *cp, location loc);
static void handle_at (int token_type, char *cp, location loc);
static void handle_syncline (char *args);
static int convert_ucn_to_byte (char const *hex_text);
static void unexpected_end_of_file (boundary, char const *);
%}
%x SC_COMMENT SC_LINE_COMMENT SC_YACC_COMMENT
%x SC_STRING SC_CHARACTER
%x SC_AFTER_IDENTIFIER
%x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER
%x SC_PRE_CODE SC_BRACED_CODE SC_PROLOGUE SC_EPILOGUE
letter [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]
id {letter}({letter}|[0-9])*
directive %{letter}({letter}|[0-9]|-)*
int [0-9]+
/* 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 IF_LINT (= 0);
/* Parent context state, when applicable. */
int context_state IF_LINT (= 0);
/* Token type to return, when applicable. */
int token_type IF_LINT (= 0);
/* Location of most recent identifier, when applicable. */
location id_loc IF_LINT (= *loc);
/* Where containing code started, when applicable. */
boundary code_start IF_LINT (= loc->start);
/* Where containing comment or string or character literal started,
when applicable. */
boundary token_start IF_LINT (= loc->start);
%}
/*-----------------------.
| Scanning white space. |
`-----------------------*/
<INITIAL,SC_AFTER_IDENTIFIER,SC_PRE_CODE>
{
[ \f\n\t\v] ;
"," warn_at (*loc, _("stray `,' treated as white space"));
/* Comments. */
"//".* ;
"/*" {
token_start = loc->start;
context_state = YY_START;
BEGIN SC_YACC_COMMENT;
}
/* #line directives are not documented, and may be withdrawn or
modified in future versions of Bison. */
^"#line "{int}" \"".*"\"\n" {
handle_syncline (yytext + sizeof "#line " - 1);
}
}
/*----------------------------.
| Scanning Bison directives. |
`----------------------------*/
<INITIAL>
{
"%binary" return PERCENT_NONASSOC;
"%debug" return PERCENT_DEBUG;
"%define" return PERCENT_DEFINE;
"%defines" return PERCENT_DEFINES;
"%destructor" token_type = PERCENT_DESTRUCTOR; BEGIN SC_PRE_CODE;
"%dprec" return PERCENT_DPREC;
"%error"[-_]"verbose" return PERCENT_ERROR_VERBOSE;
"%expect" return PERCENT_EXPECT;
"%file-prefix" return PERCENT_FILE_PREFIX;
"%fixed"[-_]"output"[-_]"files" return PERCENT_YACC;
"%glr-parser" return PERCENT_GLR_PARSER;
"%left" return PERCENT_LEFT;
"%lex-param" token_type = PERCENT_LEX_PARAM; BEGIN SC_PRE_CODE;
"%locations" return PERCENT_LOCATIONS;
"%merge" return PERCENT_MERGE;
"%name"[-_]"prefix" return PERCENT_NAME_PREFIX;
"%no"[-_]"lines" return PERCENT_NO_LINES;
"%nonassoc" return PERCENT_NONASSOC;
"%nterm" return PERCENT_NTERM;
"%output" return PERCENT_OUTPUT;
"%parse-param" token_type = PERCENT_PARSE_PARAM; BEGIN SC_PRE_CODE;
"%prec" rule_length--; return PERCENT_PREC;
"%printer" token_type = PERCENT_PRINTER; BEGIN SC_PRE_CODE;
"%pure"[-_]"parser" return PERCENT_PURE_PARSER;
"%right" return PERCENT_RIGHT;
"%skeleton" return PERCENT_SKELETON;
"%start" return PERCENT_START;
"%term" return PERCENT_TOKEN;
"%token" return PERCENT_TOKEN;
"%token"[-_]"table" return PERCENT_TOKEN_TABLE;
"%type" return PERCENT_TYPE;
"%union" token_type = PERCENT_UNION; BEGIN SC_PRE_CODE;
"%verbose" return PERCENT_VERBOSE;
"%yacc" return PERCENT_YACC;
{directive} {
complain_at (*loc, _("invalid directive: %s"), quote (yytext));
}
"=" return EQUAL;
"|" rule_length = 0; return PIPE;
";" return SEMICOLON;
{id} {
val->symbol = symbol_get (yytext, *loc);
id_loc = *loc;
rule_length++;
BEGIN SC_AFTER_IDENTIFIER;
}
{int} {
unsigned long num;
set_errno (0);
num = strtoul (yytext, 0, 10);
if (INT_MAX < num || get_errno ())
{
complain_at (*loc, _("integer out of range: %s"), quote (yytext));
num = INT_MAX;
}
val->integer = num;
return INT;
}
/* Characters. We don't check there is only one. */
"'" STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER;
/* Strings. */
"\"" STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_STRING;
/* Prologue. */
"%{" code_start = loc->start; BEGIN SC_PROLOGUE;
/* Code in between braces. */
"{" {
STRING_GROW;
token_type = BRACED_CODE;
braces_level = 0;
code_start = loc->start;
BEGIN SC_BRACED_CODE;
}
/* A type. */
"<"{tag}">" {
obstack_grow (&obstack_for_string, yytext + 1, yyleng - 2);
STRING_FINISH;
val->uniqstr = uniqstr_new (last_string);
STRING_FREE;
return TYPE;
}
"%%" {
static int percent_percent_count;
if (++percent_percent_count == 2)
{
code_start = loc->start;
BEGIN SC_EPILOGUE;
}
return PERCENT_PERCENT;
}
. {
complain_at (*loc, _("invalid character: %s"), quote (yytext));
}
}
/*-----------------------------------------------------------------.
| Scanning after an identifier, checking whether a colon is next. |
`-----------------------------------------------------------------*/
<SC_AFTER_IDENTIFIER>
{
":" {
rule_length = 0;
*loc = id_loc;
BEGIN INITIAL;
return ID_COLON;
}
. {
scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0);
yyless (0);
*loc = id_loc;
BEGIN INITIAL;
return ID;
}
<<EOF>> {
*loc = id_loc;
BEGIN INITIAL;
return ID;
}
}
/*---------------------------------------------------------------.
| Scanning a Yacc comment. The initial `/ *' is already eaten. |
`---------------------------------------------------------------*/
<SC_YACC_COMMENT>
{
"*/" BEGIN context_state;
.|\n ;
<<EOF>> unexpected_end_of_file (token_start, "*/");
}
/*------------------------------------------------------------.
| Scanning a C comment. The initial `/ *' is already eaten. |
`------------------------------------------------------------*/
<SC_COMMENT>
{
"*"{splice}"/" STRING_GROW; BEGIN context_state;
<<EOF>> unexpected_end_of_file (token_start, "*/");
}
/*--------------------------------------------------------------.
| Scanning a line comment. The initial `//' is already eaten. |
`--------------------------------------------------------------*/
<SC_LINE_COMMENT>
{
"\n" STRING_GROW; BEGIN context_state;
{splice} STRING_GROW;
<<EOF>> BEGIN context_state;
}
/*----------------------------------------------------------------.
| Scanning a C string, including its escapes. The initial `"' is |
| already eaten. |
`----------------------------------------------------------------*/
<SC_ESCAPED_STRING>
{
"\"" {
STRING_GROW;
STRING_FINISH;
loc->start = token_start;
val->chars = last_string;
rule_length++;
BEGIN INITIAL;
return STRING;
}
.|\n STRING_GROW;
<<EOF>> unexpected_end_of_file (token_start, "\"");
}
/*---------------------------------------------------------------.
| Scanning a C character, decoding its escapes. The initial "'" |
| is already eaten. |
`---------------------------------------------------------------*/
<SC_ESCAPED_CHARACTER>
{
"'" {
unsigned char last_string_1;
STRING_GROW;
STRING_FINISH;
loc->start = token_start;
val->symbol = symbol_get (last_string, *loc);
symbol_class_set (val->symbol, token_sym, *loc);
last_string_1 = last_string[1];
symbol_user_token_number_set (val->symbol, last_string_1, *loc);
STRING_FREE;
rule_length++;
BEGIN INITIAL;
return ID;
}
.|\n STRING_GROW;
<<EOF>> unexpected_end_of_file (token_start, "'");
}
/*----------------------------.
| Decode escaped characters. |
`----------------------------*/
<SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>
{
\\[0-7]{1,3} {
unsigned long c = strtoul (yytext + 1, 0, 8);
if (UCHAR_MAX < c)
complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
else
obstack_1grow (&obstack_for_string, c);
}
\\x[0-9abcdefABCDEF]+ {
unsigned long c;
set_errno (0);
c = strtoul (yytext + 2, 0, 16);
if (UCHAR_MAX < c || get_errno ())
complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
else
obstack_1grow (&obstack_for_string, c);
}
\\a obstack_1grow (&obstack_for_string, '\a');
\\b obstack_1grow (&obstack_for_string, '\b');
\\f obstack_1grow (&obstack_for_string, '\f');
\\n obstack_1grow (&obstack_for_string, '\n');
\\r obstack_1grow (&obstack_for_string, '\r');
\\t obstack_1grow (&obstack_for_string, '\t');
\\v obstack_1grow (&obstack_for_string, '\v');
/* \\[\"\'?\\] would be shorter, but it confuses xgettext. */
\\("\""|"'"|"?"|"\\") obstack_1grow (&obstack_for_string, yytext[1]);
\\(u|U[0-9abcdefABCDEF]{4})[0-9abcdefABCDEF]{4} {
int c = convert_ucn_to_byte (yytext);
if (c < 0)
complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
else
obstack_1grow (&obstack_for_string, c);
}
\\(.|\n) {
complain_at (*loc, _("unrecognized escape sequence: %s"), quote (yytext));
STRING_GROW;
}
}
/*----------------------------------------------------------.
| Scanning a C character without decoding its escapes. The |
| initial "'" is already eaten. |
`----------------------------------------------------------*/
<SC_CHARACTER>
{
"'" STRING_GROW; BEGIN context_state;
\\{splice}[^$@\[\]] STRING_GROW;
<<EOF>> unexpected_end_of_file (token_start, "'");
}
/*----------------------------------------------------------------.
| Scanning a C string, without decoding its escapes. The initial |
| `"' is already eaten. |
`----------------------------------------------------------------*/
<SC_STRING>
{
"\"" STRING_GROW; BEGIN context_state;
\\{splice}[^$@\[\]] STRING_GROW;
<<EOF>> unexpected_end_of_file (token_start, "\"");
}
/*---------------------------------------------------.
| Strings, comments etc. can be found in user code. |
`---------------------------------------------------*/
<SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>
{
"'" {
STRING_GROW;
context_state = YY_START;
token_start = loc->start;
BEGIN SC_CHARACTER;
}
"\"" {
STRING_GROW;
context_state = YY_START;
token_start = loc->start;
BEGIN SC_STRING;
}
"/"{splice}"*" {
STRING_GROW;
context_state = YY_START;
token_start = loc->start;
BEGIN SC_COMMENT;
}
"/"{splice}"/" {
STRING_GROW;
context_state = YY_START;
BEGIN SC_LINE_COMMENT;
}
}
/*---------------------------------------------------------------.
| Scanning after %union etc., possibly followed by white space. |
| For %union only, allow arbitrary C code to appear before the |
| following brace, as an extension to POSIX. |
`---------------------------------------------------------------*/
<SC_PRE_CODE>
{
. {
bool valid = yytext[0] == '{' || token_type == PERCENT_UNION;
scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0);
yyless (0);
if (valid)
{
braces_level = -1;
code_start = loc->start;
BEGIN SC_BRACED_CODE;
}
else
{
complain_at (*loc, _("missing `{' in `%s'"),
token_name (token_type));
obstack_sgrow (&obstack_for_string, "{}");
STRING_FINISH;
val->chars = last_string;
BEGIN INITIAL;
return token_type;
}
}
}
/*---------------------------------------------------------------.
| Scanning some code in braces (%union and actions). The initial |
| "{" is already eaten. |
`---------------------------------------------------------------*/
<SC_BRACED_CODE>
{
"{"|"<"{splice}"%" STRING_GROW; braces_level++;
"%"{splice}">" 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.
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 && token_type == BRACED_CODE && ! yacc_flag)
obstack_1grow (&obstack_for_string, ';');
obstack_1grow (&obstack_for_string, '}');
if (outer_brace)
{
STRING_FINISH;
rule_length++;
loc->start = code_start;
val->chars = last_string;
BEGIN INITIAL;
return token_type;
}
}
/* Tokenize `<<%' correctly (as `<<' `%') rather than incorrrectly
(as `<' `<%'). */
"<"{splice}"<" STRING_GROW;
"$"("<"{tag}">")?(-?[0-9]+|"$") handle_dollar (token_type, yytext, *loc);
"@"(-?[0-9]+|"$") handle_at (token_type, yytext, *loc);
<<EOF>> unexpected_end_of_file (code_start, "}");
}
/*--------------------------------------------------------------.
| Scanning some prologue: from "%{" (already scanned) to "%}". |
`--------------------------------------------------------------*/
<SC_PROLOGUE>
{
"%}" {
STRING_FINISH;
loc->start = code_start;
val->chars = last_string;
BEGIN INITIAL;
return PROLOGUE;
}
<<EOF>> unexpected_end_of_file (code_start, "%}");
}
/*---------------------------------------------------------------.
| Scanning the epilogue (everything after the second "%%", which |
| has already been eaten). |
`---------------------------------------------------------------*/
<SC_EPILOGUE>
{
<<EOF>> {
STRING_FINISH;
loc->start = code_start;
val->chars = last_string;
BEGIN INITIAL;
return EPILOGUE;
}
}
/*----------------------------------------------------------------.
| By default, grow the string obstack with the input, escaping M4 |
| quoting characters. |
`----------------------------------------------------------------*/
<SC_COMMENT,SC_LINE_COMMENT,SC_STRING,SC_CHARACTER,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>
{
\$ obstack_sgrow (&obstack_for_string, "$][");
\@ obstack_sgrow (&obstack_for_string, "@@");
\[ obstack_sgrow (&obstack_for_string, "@{");
\] obstack_sgrow (&obstack_for_string, "@}");
.|\n STRING_GROW;
}
%%
/* Set *LOC and adjust scanner cursor to account for token TOKEN of
size SIZE. */
static void
adjust_location (location *loc, char const *token, size_t size)
{
int line = scanner_cursor.line;
int column = scanner_cursor.column;
char const *p0 = token;
char const *p = token;
char const *lim = token + size;
loc->start = scanner_cursor;
for (p = token; p < lim; p++)
switch (*p)
{
case '\n':
line++;
column = 1;
p0 = p + 1;
break;
case '\t':
column += mbsnwidth (p0, p - p0, 0);
column += 8 - ((column - 1) & 7);
p0 = p + 1;
break;
}
scanner_cursor.line = line;
scanner_cursor.column = column + mbsnwidth (p0, p - p0, 0);
loc->end = scanner_cursor;
}
/* Read bytes from FP into buffer BUF of size SIZE. Return the
number of bytes read. Remove '\r' from input, treating \r\n
and isolated \r as \n. */
static size_t
no_cr_read (FILE *fp, char *buf, size_t size)
{
size_t bytes_read = fread (buf, 1, size, fp);
if (bytes_read)
{
char *w = memchr (buf, '\r', bytes_read);
if (w)
{
char const *r = ++w;
char const *lim = buf + bytes_read;
for (;;)
{
/* Found an '\r'. Treat it like '\n', but ignore any
'\n' that immediately follows. */
w[-1] = '\n';
if (r == lim)
{
int ch = getc (fp);
if (ch != '\n' && ungetc (ch, fp) != ch)
break;
}
else if (*r == '\n')
r++;
/* Copy until the next '\r'. */
do
{
if (r == lim)
return w - buf;
}
while ((*w++ = *r++) != '\r');
}
return w - buf;
}
}
return bytes_read;
}
/*------------------------------------------------------------------.
| 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 inline bool
handle_action_dollar (char *text, location loc)
{
const char *type_name = NULL;
char *cp = text + 1;
if (! current_rule)
return false;
/* Get the type name if explicit. */
if (*cp == '<')
{
type_name = ++cp;
while (*cp != '>')
++cp;
*cp = '\0';
++cp;
}
if (*cp == '$')
{
if (!type_name)
type_name = symbol_list_n_type_name_get (current_rule, loc, 0);
if (!type_name && typed)
complain_at (loc, _("$$ of `%s' has no declared type"),
current_rule->sym->tag);
if (!type_name)
type_name = "";
obstack_fgrow1 (&obstack_for_string,
"]b4_lhs_value([%s])[", type_name);
}
else
{
long num;
set_errno (0);
num = strtol (cp, 0, 10);
if (INT_MIN <= num && num <= rule_length && ! get_errno ())
{
int n = num;
if (!type_name && n > 0)
type_name = symbol_list_n_type_name_get (current_rule, loc, n);
if (!type_name && typed)
complain_at (loc, _("$%d of `%s' has no declared type"),
n, current_rule->sym->tag);
if (!type_name)
type_name = "";
obstack_fgrow3 (&obstack_for_string,
"]b4_rhs_value([%d], [%d], [%s])[",
rule_length, n, type_name);
}
else
complain_at (loc, _("integer out of range: %s"), quote (text));
}
return true;
}
/*-----------------------------------------------------------------.
| Dispatch onto handle_action_dollar, or handle_destructor_dollar, |
| depending upon TOKEN_TYPE. |
`-----------------------------------------------------------------*/
static void
handle_dollar (int token_type, char *text, location loc)
{
switch (token_type)
{
case BRACED_CODE:
if (handle_action_dollar (text, loc))
return;
break;
case PERCENT_DESTRUCTOR:
case PERCENT_PRINTER:
if (text[1] == '$')
{
obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
return;
}
break;
default:
break;
}
complain_at (loc, _("invalid value: %s"), quote (text));
}
/*------------------------------------------------------.
| TEXT is a location token (i.e., a `@...'). Output to |
| OBSTACK_FOR_STRING a reference to this location. |
`------------------------------------------------------*/
static inline bool
handle_action_at (char *text, location loc)
{
char *cp = text + 1;
locations_flag = 1;
if (! current_rule)
return false;
if (*cp == '$')
obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
else
{
long num;
set_errno (0);
num = strtol (cp, 0, 10);
if (INT_MIN <= num && num <= rule_length && ! get_errno ())
{
int n = num;
obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location([%d], [%d])[",
rule_length, n);
}
else
complain_at (loc, _("integer out of range: %s"), quote (text));
}
return true;
}
/*-------------------------------------------------------------------.
| Dispatch onto handle_action_at, or handle_destructor_at, depending |
| upon CODE_KIND. |
`-------------------------------------------------------------------*/
static void
handle_at (int token_type, char *text, location loc)
{
switch (token_type)
{
case BRACED_CODE:
handle_action_at (text, loc);
return;
case PERCENT_DESTRUCTOR:
case PERCENT_PRINTER:
if (text[1] == '$')
{
obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
return;
}
break;
default:
break;
}
complain_at (loc, _("invalid value: %s"), quote (text));
}
/*------------------------------------------------------------------.
| Convert universal character name UCN to a single-byte character, |
| and return that character. Return -1 if UCN does not correspond |
| to a single-byte character. |
`------------------------------------------------------------------*/
static int
convert_ucn_to_byte (char const *ucn)
{
unsigned long code = strtoul (ucn + 2, 0, 16);
/* FIXME: Currently we assume Unicode-compatible unibyte characters
on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes). On
non-ASCII hosts we support only the portable C character set.
These limitations should be removed once we add support for
multibyte characters. */
if (UCHAR_MAX < code)
return -1;
#if ! ('$' == 0x24 && '@' == 0x40 && '`' == 0x60 && '~' == 0x7e)
{
/* A non-ASCII host. Use CODE to index into a table of the C
basic execution character set, which is guaranteed to exist on
all Standard C platforms. This table also includes '$', '@',
and '`', which are not in the basic execution character set but
which are unibyte characters on all the platforms that we know
about. */
static signed char const table[] =
{
'\0', -1, -1, -1, -1, -1, -1, '\a',
'\b', '\t', '\n', '\v', '\f', '\r', -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
' ', '!', '"', '#', '$', '%', '&', '\'',
'(', ')', '*', '+', ',', '-', '.', '/',
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', ':', ';', '<', '=', '>', '?',
'@', 'A', 'B', 'C', 'D', 'E', 'F', 'G',
'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
'X', 'Y', 'Z', '[', '\\', ']', '^', '_',
'`', 'a', 'b', 'c', 'd', 'e', 'f', 'g',
'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
'p', 'q', 'r', 's', 't', 'u', 'v', 'w',
'x', 'y', 'z', '{', '|', '}', '~'
};
code = code < sizeof table ? table[code] : -1;
}
#endif
return code;
}
/*----------------------------------------------------------------.
| Handle `#line INT "FILE"'. ARGS has already skipped `#line '. |
`----------------------------------------------------------------*/
static void
handle_syncline (char *args)
{
int lineno = strtol (args, &args, 10);
const char *file = NULL;
file = strchr (args, '"') + 1;
*strchr (file, '"') = 0;
scanner_cursor.file = current_file = xstrdup (file);
scanner_cursor.line = lineno;
scanner_cursor.column = 1;
}
/*------------------------------------------------------------------------.
| Report an unexpected EOF in a token or comment starting at START. |
| An end of file was encountered and the expected TOKEN_END was missing. |
| After reporting the problem, pretend that TOKEN_END was found. |
`------------------------------------------------------------------------*/
static void
unexpected_end_of_file (boundary start, char const *token_end)
{
size_t i = strlen (token_end);
location loc;
loc.start = start;
loc.end = scanner_cursor;
complain_at (loc, _("missing `%s' at end of file"), token_end);
/* Adjust scanner cursor so that any later message does not count
the characters about to be inserted. */
scanner_cursor.column -= i;
while (i != 0)
unput (token_end[--i]);
}
/*-------------------------.
| Initialize the scanner. |
`-------------------------*/
void
scanner_initialize (void)
{
obstack_init (&obstack_for_string);
}
/*-----------------------------------------------.
| Free all the memory allocated to the scanner. |
`-----------------------------------------------*/
void
scanner_free (void)
{
obstack_free (&obstack_for_string, 0);
/* Reclaim Flex's buffers. */
yy_delete_buffer (YY_CURRENT_BUFFER);
}
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