[1/2] dtc: Simplify lexing/parsing of literals vs. node/property names
David Gibson
david at gibson.dropbear.id.au
Fri Oct 26 16:19:41 EST 2007
The current scheme of having CELLDATA and MEMRESERVE states to
recognize hex literals instead of node or property names is
arse-backwards. The patch switches things around so that literals are
lexed in normal states, and property/node names are only recognized in
the special PROPNODENAME state, which is only entered after a { or a
;, and is left as soon as we scan a property/node name or a keyword.
Signed-off-by: David Gibson <david at gibson.dropbear.id.au>
---
dtc-lexer.l | 105 +++++++++++---------------------------------------
dtc-parser.y | 123 ++++++++++++++++++++++++++---------------------------------
2 files changed, 80 insertions(+), 148 deletions(-)
Index: dtc/dtc-lexer.l
===================================================================
--- dtc.orig/dtc-lexer.l 2007-10-26 12:54:30.000000000 +1000
+++ dtc/dtc-lexer.l 2007-10-26 15:11:02.000000000 +1000
@@ -21,9 +21,8 @@
%option noyywrap nounput yylineno
%x INCLUDE
-%x CELLDATA
%x BYTESTRING
-%x MEMRESERVE
+%x PROPNODENAME
PROPCHAR [a-zA-Z0-9,._+*#?-]
UNITCHAR [0-9a-f,]
@@ -51,7 +50,7 @@
%%
-"/include/" BEGIN(INCLUDE);
+<*>"/include/" BEGIN(INCLUDE);
<INCLUDE>\"[^"\n]*\" {
yytext[strlen(yytext) - 1] = 0;
@@ -63,13 +62,13 @@
}
-<<EOF>> {
+<*><<EOF>> {
if (!pop_input_file()) {
yyterminate();
}
}
-\"([^\\"]|\\.)*\" {
+<*>\"([^\\"]|\\.)*\" {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
DPRINT("String: %s\n", yytext);
@@ -79,45 +78,24 @@
return DT_STRING;
}
-"/memreserve/" {
+<*>"/memreserve/" {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
DPRINT("Keyword: /memreserve/\n");
- BEGIN(MEMRESERVE);
- return DT_MEMRESERVE;
- }
-
-<MEMRESERVE>[0-9a-fA-F]+ {
- yylloc.filenum = srcpos_filenum;
- yylloc.first_line = yylineno;
- if (yyleng > 2*sizeof(yylval.addr)) {
- fprintf(stderr, "Address value %s too large\n",
- yytext);
- }
- yylval.addr = (u64) strtoull(yytext, NULL, 16);
- DPRINT("Addr: %llx\n",
- (unsigned long long)yylval.addr);
- return DT_ADDR;
- }
-
-<MEMRESERVE>";" {
- yylloc.filenum = srcpos_filenum;
- yylloc.first_line = yylineno;
- DPRINT("/MEMRESERVE\n");
BEGIN(INITIAL);
- return ';';
+ return DT_MEMRESERVE;
}
<*>[a-zA-Z_][a-zA-Z0-9_]*: {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
DPRINT("Label: %s\n", yytext);
- yylval.str = strdup(yytext);
- yylval.str[yyleng-1] = '\0';
+ yylval.labelref = strdup(yytext);
+ yylval.labelref[yyleng-1] = '\0';
return DT_LABEL;
}
-<CELLDATA>[bodh]# {
+[bodh]# {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
if (*yytext == 'b')
@@ -132,27 +110,19 @@
return DT_BASE;
}
-<CELLDATA>[0-9a-fA-F]+ {
- yylloc.filenum = srcpos_filenum;
- yylloc.first_line = yylineno;
- yylval.str = strdup(yytext);
- DPRINT("Cell: '%s'\n", yylval.str);
- return DT_CELL;
- }
-
-<CELLDATA>">" {
+[0-9a-fA-F]+ {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
- DPRINT("/CELLDATA\n");
- BEGIN(INITIAL);
- return '>';
+ yylval.literal = strdup(yytext);
+ DPRINT("Literal: '%s'\n", yylval.literal);
+ return DT_LITERAL;
}
-<CELLDATA>\&{REFCHAR}* {
+\&{REFCHAR}* {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
DPRINT("Ref: %s\n", yytext+1);
- yylval.str = strdup(yytext+1);
+ yylval.labelref = strdup(yytext+1);
return DT_REF;
}
@@ -172,30 +142,13 @@
return ']';
}
-, { /* Technically this is a valid property name,
- but we'd rather use it as punctuation, so detect it
- here in preference */
- yylloc.filenum = srcpos_filenum;
- yylloc.first_line = yylineno;
- DPRINT("Char (propname like): %c (\\x%02x)\n", yytext[0],
- (unsigned)yytext[0]);
- return yytext[0];
- }
-
-{PROPCHAR}+ {
+<PROPNODENAME>{PROPCHAR}+(@{UNITCHAR}+)? {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
- DPRINT("PropName: %s\n", yytext);
- yylval.str = strdup(yytext);
- return DT_PROPNAME;
- }
-
-{PROPCHAR}+(@{UNITCHAR}+)? {
- yylloc.filenum = srcpos_filenum;
- yylloc.first_line = yylineno;
- DPRINT("NodeName: %s\n", yytext);
- yylval.str = strdup(yytext);
- return DT_NODENAME;
+ DPRINT("PropNodeName: %s\n", yytext);
+ yylval.propnodename = strdup(yytext);
+ BEGIN(INITIAL);
+ return DT_PROPNODENAME;
}
@@ -213,21 +166,13 @@
<*>. {
yylloc.filenum = srcpos_filenum;
yylloc.first_line = yylineno;
- switch (yytext[0]) {
- case '<':
- DPRINT("CELLDATA\n");
- BEGIN(CELLDATA);
- break;
- case '[':
- DPRINT("BYTESTRING\n");
- BEGIN(BYTESTRING);
- break;
- default:
-
+ if ((yytext[0] == '{')
+ || (yytext[0] == ';')) {
+ DPRINT("<PROPNODENAME>\n");
+ BEGIN(PROPNODENAME);
+ }
DPRINT("Char: %c (\\x%02x)\n", yytext[0],
(unsigned)yytext[0]);
- break;
- }
return yytext[0];
}
Index: dtc/dtc-parser.y
===================================================================
--- dtc.orig/dtc-parser.y 2007-10-26 13:00:21.000000000 +1000
+++ dtc/dtc-parser.y 2007-10-26 15:11:02.000000000 +1000
@@ -25,45 +25,46 @@
#include "srcpos.h"
int yylex(void);
-cell_t cell_from_string(char *s, unsigned int base);
+unsigned long long eval_literal(const char *s, int base, int bits);
extern struct boot_info *the_boot_info;
%}
%union {
- cell_t cval;
+ char *propnodename;
+ char *literal;
+ char *labelref;
unsigned int cbase;
u8 byte;
- char *str;
struct data data;
+
+ u64 addr;
+ cell_t cell;
struct property *prop;
struct property *proplist;
struct node *node;
struct node *nodelist;
- int datalen;
- int hexlen;
- u64 addr;
struct reserve_info *re;
}
%token DT_MEMRESERVE
-%token <addr> DT_ADDR
-%token <str> DT_PROPNAME
-%token <str> DT_NODENAME
+%token <propnodename> DT_PROPNODENAME
+%token <literal> DT_LITERAL
%token <cbase> DT_BASE
-%token <str> DT_CELL
%token <byte> DT_BYTE
%token <data> DT_STRING
-%token <str> DT_LABEL
-%token <str> DT_REF
+%token <labelref> DT_LABEL
+%token <labelref> DT_REF
%type <data> propdata
%type <data> propdataprefix
%type <re> memreserve
%type <re> memreserves
-%type <cbase> opt_cell_base
+%type <addr> addr
%type <data> celllist
+%type <cbase> cellbase
+%type <cell> cellval
%type <data> bytestring
%type <prop> propdef
%type <proplist> proplist
@@ -72,8 +73,7 @@
%type <node> nodedef
%type <node> subnode
%type <nodelist> subnodes
-%type <str> label
-%type <str> nodename
+%type <labelref> label
%%
@@ -96,16 +96,23 @@
;
memreserve:
- label DT_MEMRESERVE DT_ADDR DT_ADDR ';'
+ label DT_MEMRESERVE addr addr ';'
{
$$ = build_reserve_entry($3, $4, $1);
}
- | label DT_MEMRESERVE DT_ADDR '-' DT_ADDR ';'
+ | label DT_MEMRESERVE addr '-' addr ';'
{
$$ = build_reserve_entry($3, $5 - $3 + 1, $1);
}
;
+addr:
+ DT_LITERAL
+ {
+ $$ = eval_literal($1, 16, 64);
+ }
+ ;
+
devicetree:
'/' nodedef
{
@@ -132,11 +139,11 @@
;
propdef:
- label DT_PROPNAME '=' propdata ';'
+ label DT_PROPNODENAME '=' propdata ';'
{
$$ = build_property($2, $4, $1);
}
- | label DT_PROPNAME ';'
+ | label DT_PROPNODENAME ';'
{
$$ = build_property($2, empty_data, $1);
}
@@ -177,23 +184,14 @@
}
;
-opt_cell_base:
- /* empty */
- {
- $$ = 16;
- }
- | DT_BASE
- ;
-
celllist:
/* empty */
{
$$ = empty_data;
}
- | celllist opt_cell_base DT_CELL
+ | celllist cellval
{
- $$ = data_append_cell($1,
- cell_from_string($3, $2));
+ $$ = data_append_cell($1, $2);
}
| celllist DT_REF
{
@@ -205,6 +203,21 @@
}
;
+cellbase:
+ /* empty */
+ {
+ $$ = 16;
+ }
+ | DT_BASE
+ ;
+
+cellval:
+ cellbase DT_LITERAL
+ {
+ $$ = eval_literal($2, $1, 32);
+ }
+ ;
+
bytestring:
/* empty */
{
@@ -232,23 +245,12 @@
;
subnode:
- label nodename nodedef
+ label DT_PROPNODENAME nodedef
{
$$ = name_node($3, $2, $1);
}
;
-nodename:
- DT_NODENAME
- {
- $$ = $1;
- }
- | DT_PROPNAME
- {
- $$ = $1;
- }
- ;
-
label:
/* empty */
{
@@ -273,33 +275,18 @@
fname, yylloc.first_line, s);
}
-
-/*
- * Convert a string representation of a numeric cell
- * in the given base into a cell.
- *
- * FIXME: should these specification errors be fatal instead?
- */
-
-cell_t cell_from_string(char *s, unsigned int base)
+unsigned long long eval_literal(const char *s, int base, int bits)
{
- cell_t c;
+ unsigned long long val;
char *e;
- c = strtoul(s, &e, base);
- if (*e) {
- fprintf(stderr,
- "Line %d: Invalid cell value '%s' : "
- "%c is not a base %d digit; %d assumed\n",
- yylloc.first_line, s, *e, base, c);
- }
-
- if (errno == EINVAL || errno == ERANGE) {
- fprintf(stderr,
- "Line %d: Invalid cell value '%s'; %d assumed\n",
- yylloc.first_line, s, c);
- errno = 0;
- }
-
- return c;
+ errno = 0;
+ val = strtoull(s, &e, base);
+ if (*e)
+ yyerror("bad characters in literal");
+ else if ((errno == ERANGE) || (val > ((1ULL << bits)-1)))
+ yyerror("literal out of range");
+ else if (errno != 0)
+ yyerror("bad literal");
+ return val;
}
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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