linux/scripts/genksyms/lex.l

408 lines
7.7 KiB
Plaintext

/* Lexical analysis for genksyms.
Copyright 1996, 1997 Linux International.
New implementation contributed by Richard Henderson <rth@tamu.edu>
Based on original work by Bjorn Ekwall <bj0rn@blox.se>
Taken from Linux modutils 2.4.22.
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. */
%{
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "genksyms.h"
#include "parse.h"
/* We've got a two-level lexer here. We let flex do basic tokenization
and then we categorize those basic tokens in the second stage. */
#define YY_DECL static int yylex1(void)
%}
IDENT [A-Za-z_\$][A-Za-z0-9_\$]*
O_INT 0[0-7]*
D_INT [1-9][0-9]*
X_INT 0[Xx][0-9A-Fa-f]+
I_SUF [Uu]|[Ll]|[Uu][Ll]|[Ll][Uu]
INT ({O_INT}|{D_INT}|{X_INT}){I_SUF}?
FRAC ([0-9]*\.[0-9]+)|([0-9]+\.)
EXP [Ee][+-]?[0-9]+
F_SUF [FfLl]
REAL ({FRAC}{EXP}?{F_SUF}?)|([0-9]+{EXP}{F_SUF}?)
STRING L?\"([^\\\"]*\\.)*[^\\\"]*\"
CHAR L?\'([^\\\']*\\.)*[^\\\']*\'
MC_TOKEN ([~%^&*+=|<>/-]=)|(&&)|("||")|(->)|(<<)|(>>)
/* Version 2 checksumming does proper tokenization; version 1 wasn't
quite so pedantic. */
%s V2_TOKENS
/* We don't do multiple input files. */
%option noyywrap
%%
/* Keep track of our location in the original source files. */
^#[ \t]+{INT}[ \t]+\"[^\"\n]+\".*\n return FILENAME;
^#.*\n cur_line++;
\n cur_line++;
/* Ignore all other whitespace. */
[ \t\f\v\r]+ ;
{STRING} return STRING;
{CHAR} return CHAR;
{IDENT} return IDENT;
/* The Pedant requires that the other C multi-character tokens be
recognized as tokens. We don't actually use them since we don't
parse expressions, but we do want whitespace to be arranged
around them properly. */
<V2_TOKENS>{MC_TOKEN} return OTHER;
<V2_TOKENS>{INT} return INT;
<V2_TOKENS>{REAL} return REAL;
"..." return DOTS;
/* All other tokens are single characters. */
. return yytext[0];
%%
/* Bring in the keyword recognizer. */
#include "keywords.c"
/* Macros to append to our phrase collection list. */
#define _APP(T,L) do { \
cur_node = next_node; \
next_node = xmalloc(sizeof(*next_node)); \
next_node->next = cur_node; \
cur_node->string = memcpy(xmalloc(L+1), T, L+1); \
cur_node->tag = SYM_NORMAL; \
} while (0)
#define APP _APP(yytext, yyleng)
/* The second stage lexer. Here we incorporate knowledge of the state
of the parser to tailor the tokens that are returned. */
int
yylex(void)
{
static enum {
ST_NOTSTARTED, ST_NORMAL, ST_ATTRIBUTE, ST_ASM, ST_BRACKET, ST_BRACE,
ST_EXPRESSION, ST_TABLE_1, ST_TABLE_2, ST_TABLE_3, ST_TABLE_4,
ST_TABLE_5, ST_TABLE_6
} lexstate = ST_NOTSTARTED;
static int suppress_type_lookup, dont_want_brace_phrase;
static struct string_list *next_node;
int token, count = 0;
struct string_list *cur_node;
if (lexstate == ST_NOTSTARTED)
{
BEGIN(V2_TOKENS);
next_node = xmalloc(sizeof(*next_node));
next_node->next = NULL;
lexstate = ST_NORMAL;
}
repeat:
token = yylex1();
if (token == 0)
return 0;
else if (token == FILENAME)
{
char *file, *e;
/* Save the filename and line number for later error messages. */
if (cur_filename)
free(cur_filename);
file = strchr(yytext, '\"')+1;
e = strchr(file, '\"');
*e = '\0';
cur_filename = memcpy(xmalloc(e-file+1), file, e-file+1);
cur_line = atoi(yytext+2);
goto repeat;
}
switch (lexstate)
{
case ST_NORMAL:
switch (token)
{
case IDENT:
APP;
{
const struct resword *r = is_reserved_word(yytext, yyleng);
if (r)
{
switch (token = r->token)
{
case ATTRIBUTE_KEYW:
lexstate = ST_ATTRIBUTE;
count = 0;
goto repeat;
case ASM_KEYW:
lexstate = ST_ASM;
count = 0;
goto repeat;
case STRUCT_KEYW:
case UNION_KEYW:
dont_want_brace_phrase = 3;
case ENUM_KEYW:
suppress_type_lookup = 2;
goto fini;
case EXPORT_SYMBOL_KEYW:
goto fini;
}
}
if (!suppress_type_lookup)
{
struct symbol *sym = find_symbol(yytext, SYM_TYPEDEF);
if (sym && sym->type == SYM_TYPEDEF)
token = TYPE;
}
}
break;
case '[':
APP;
lexstate = ST_BRACKET;
count = 1;
goto repeat;
case '{':
APP;
if (dont_want_brace_phrase)
break;
lexstate = ST_BRACE;
count = 1;
goto repeat;
case '=': case ':':
APP;
lexstate = ST_EXPRESSION;
break;
case DOTS:
default:
APP;
break;
}
break;
case ST_ATTRIBUTE:
APP;
switch (token)
{
case '(':
++count;
goto repeat;
case ')':
if (--count == 0)
{
lexstate = ST_NORMAL;
token = ATTRIBUTE_PHRASE;
break;
}
goto repeat;
default:
goto repeat;
}
break;
case ST_ASM:
APP;
switch (token)
{
case '(':
++count;
goto repeat;
case ')':
if (--count == 0)
{
lexstate = ST_NORMAL;
token = ASM_PHRASE;
break;
}
goto repeat;
default:
goto repeat;
}
break;
case ST_BRACKET:
APP;
switch (token)
{
case '[':
++count;
goto repeat;
case ']':
if (--count == 0)
{
lexstate = ST_NORMAL;
token = BRACKET_PHRASE;
break;
}
goto repeat;
default:
goto repeat;
}
break;
case ST_BRACE:
APP;
switch (token)
{
case '{':
++count;
goto repeat;
case '}':
if (--count == 0)
{
lexstate = ST_NORMAL;
token = BRACE_PHRASE;
break;
}
goto repeat;
default:
goto repeat;
}
break;
case ST_EXPRESSION:
switch (token)
{
case '(': case '[': case '{':
++count;
APP;
goto repeat;
case ')': case ']': case '}':
--count;
APP;
goto repeat;
case ',': case ';':
if (count == 0)
{
/* Put back the token we just read so's we can find it again
after registering the expression. */
unput(token);
lexstate = ST_NORMAL;
token = EXPRESSION_PHRASE;
break;
}
APP;
goto repeat;
default:
APP;
goto repeat;
}
break;
case ST_TABLE_1:
goto repeat;
case ST_TABLE_2:
if (token == IDENT && yyleng == 1 && yytext[0] == 'X')
{
token = EXPORT_SYMBOL_KEYW;
lexstate = ST_TABLE_5;
APP;
break;
}
lexstate = ST_TABLE_6;
/* FALLTHRU */
case ST_TABLE_6:
switch (token)
{
case '{': case '[': case '(':
++count;
break;
case '}': case ']': case ')':
--count;
break;
case ',':
if (count == 0)
lexstate = ST_TABLE_2;
break;
};
goto repeat;
case ST_TABLE_3:
goto repeat;
case ST_TABLE_4:
if (token == ';')
lexstate = ST_NORMAL;
goto repeat;
case ST_TABLE_5:
switch (token)
{
case ',':
token = ';';
lexstate = ST_TABLE_2;
APP;
break;
default:
APP;
break;
}
break;
default:
abort();
}
fini:
if (suppress_type_lookup > 0)
--suppress_type_lookup;
if (dont_want_brace_phrase > 0)
--dont_want_brace_phrase;
yylval = &next_node->next;
return token;
}