platform_external_dtc/dtc-lexer.l
David Gibson 8a88ad8bad dtc: Remove ugly include stack abuse
Currently, dt_from_source() uses push_input_file() to set up the
initial input file for the lexer.  That sounds sensible - put the
outermost input file at the bottom of the stack - until you realise
that what it *actually* does is pushes the current, uninitialized,
lexer input state onto the stack, then sets up the new lexer input.

That necessitates an extra check in pop_input_file(), rather than
signalling termination in the natural way when the include stack is
empty, it has to check when it pops the bogus uninitialized state off
the stack.  Ick.

With that fixed, push_input_file(), pop_input_file() and
incl_file_stack itself become local to the lexer, so make them static.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2008-03-23 08:00:33 -05:00

319 lines
6.7 KiB
Text

/*
* (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation. 2005.
*
*
* 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 noyywrap nounput yylineno stack
%x INCLUDE
%x BYTESTRING
%x PROPNODENAME
%s V1
PROPNODECHAR [a-zA-Z0-9,._+*#?@-]
PATHCHAR ({PROPNODECHAR}|[/])
LABEL [a-zA-Z_][a-zA-Z0-9_]*
%{
#include "dtc.h"
#include "srcpos.h"
#include "dtc-parser.tab.h"
/*#define LEXDEBUG 1*/
#ifdef LEXDEBUG
#define DPRINT(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)
#else
#define DPRINT(fmt, ...) do { } while (0)
#endif
static int dts_version; /* = 0 */
#define BEGIN_DEFAULT() if (dts_version == 0) { \
DPRINT("<INITIAL>\n"); \
BEGIN(INITIAL); \
} else { \
DPRINT("<V1>\n"); \
BEGIN(V1); \
}
static void push_input_file(const char *filename);
static int pop_input_file(void);
%}
%%
<*>"/include/" yy_push_state(INCLUDE);
<INCLUDE>\"[^"\n]*\" {
yytext[strlen(yytext) - 1] = 0;
push_input_file(yytext + 1);
yy_pop_state();
}
<*><<EOF>> {
if (!pop_input_file()) {
yyterminate();
}
}
<*>\"([^\\"]|\\.)*\" {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("String: %s\n", yytext);
yylval.data = data_copy_escape_string(yytext+1,
yyleng-2);
yylloc.first_line = yylineno;
return DT_STRING;
}
<*>"/dts-v1/" {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Keyword: /dts-v1/\n");
dts_version = 1;
BEGIN_DEFAULT();
return DT_V1;
}
<*>"/memreserve/" {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Keyword: /memreserve/\n");
BEGIN_DEFAULT();
return DT_MEMRESERVE;
}
<*>{LABEL}: {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Label: %s\n", yytext);
yylval.labelref = strdup(yytext);
yylval.labelref[yyleng-1] = '\0';
return DT_LABEL;
}
<INITIAL>[bodh]# {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
if (*yytext == 'b')
yylval.cbase = 2;
else if (*yytext == 'o')
yylval.cbase = 8;
else if (*yytext == 'd')
yylval.cbase = 10;
else
yylval.cbase = 16;
DPRINT("Base: %d\n", yylval.cbase);
return DT_BASE;
}
<INITIAL>[0-9a-fA-F]+ {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
yylval.literal = strdup(yytext);
DPRINT("Literal: '%s'\n", yylval.literal);
return DT_LEGACYLITERAL;
}
<V1>[0-9]+|0[xX][0-9a-fA-F]+ {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
yylval.literal = strdup(yytext);
DPRINT("Literal: '%s'\n", yylval.literal);
return DT_LITERAL;
}
\&{LABEL} { /* label reference */
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Ref: %s\n", yytext+1);
yylval.labelref = strdup(yytext+1);
return DT_REF;
}
"&{/"{PATHCHAR}+\} { /* new-style path reference */
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
yytext[yyleng-1] = '\0';
DPRINT("Ref: %s\n", yytext+2);
yylval.labelref = strdup(yytext+2);
return DT_REF;
}
<INITIAL>"&/"{PATHCHAR}+ { /* old-style path reference */
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Ref: %s\n", yytext+1);
yylval.labelref = strdup(yytext+1);
return DT_REF;
}
<BYTESTRING>[0-9a-fA-F]{2} {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
yylval.byte = strtol(yytext, NULL, 16);
DPRINT("Byte: %02x\n", (int)yylval.byte);
return DT_BYTE;
}
<BYTESTRING>"]" {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("/BYTESTRING\n");
BEGIN_DEFAULT();
return ']';
}
<PROPNODENAME>{PROPNODECHAR}+ {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("PropNodeName: %s\n", yytext);
yylval.propnodename = strdup(yytext);
BEGIN_DEFAULT();
return DT_PROPNODENAME;
}
<*>[[:space:]]+ /* eat whitespace */
<*>"/*"([^*]|\*+[^*/])*\*+"/" {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Comment: %s\n", yytext);
/* eat comments */
}
<*>"//".*\n /* eat line comments */
<*>. {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("Char: %c (\\x%02x)\n", yytext[0],
(unsigned)yytext[0]);
if (yytext[0] == '[') {
DPRINT("<BYTESTRING>\n");
BEGIN(BYTESTRING);
}
if ((yytext[0] == '{')
|| (yytext[0] == ';')) {
DPRINT("<PROPNODENAME>\n");
BEGIN(PROPNODENAME);
}
return yytext[0];
}
%%
/*
* Stack of nested include file contexts.
*/
struct incl_file {
struct dtc_file *file;
YY_BUFFER_STATE yy_prev_buf;
int yy_prev_lineno;
struct incl_file *prev;
};
static struct incl_file *incl_file_stack;
/*
* Detect infinite include recursion.
*/
#define MAX_INCLUDE_DEPTH (100)
static int incl_depth = 0;
static void push_input_file(const char *filename)
{
struct incl_file *incl_file;
struct dtc_file *newfile;
struct search_path search, *searchptr = NULL;
assert(filename);
if (incl_depth++ >= MAX_INCLUDE_DEPTH)
die("Includes nested too deeply");
if (srcpos_file) {
search.dir = srcpos_file->dir;
search.next = NULL;
search.prev = NULL;
searchptr = &search;
}
newfile = dtc_open_file(filename, searchptr);
incl_file = xmalloc(sizeof(struct incl_file));
/*
* Save current context.
*/
incl_file->yy_prev_buf = YY_CURRENT_BUFFER;
incl_file->yy_prev_lineno = yylineno;
incl_file->file = srcpos_file;
incl_file->prev = incl_file_stack;
incl_file_stack = incl_file;
/*
* Establish new context.
*/
srcpos_file = newfile;
yylineno = 1;
yyin = newfile->file;
yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
}
static int pop_input_file(void)
{
struct incl_file *incl_file;
if (incl_file_stack == 0)
return 0;
dtc_close_file(srcpos_file);
/*
* Pop.
*/
--incl_depth;
incl_file = incl_file_stack;
incl_file_stack = incl_file->prev;
/*
* Recover old context.
*/
yy_delete_buffer(YY_CURRENT_BUFFER);
yy_switch_to_buffer(incl_file->yy_prev_buf);
yylineno = incl_file->yy_prev_lineno;
srcpos_file = incl_file->file;
yyin = incl_file->file ? incl_file->file->file : NULL;
/*
* Free old state.
*/
free(incl_file);
return 1;
}