Currently we scan the /include/ directive as two tokens, the
"/include/" keyword itself, then the string giving the file name to
include. We use a special scanner state to keep the two linked
together, and use the scanner state stack to keep track of the
original state while we're parsing the two /include/ tokens.
This does mean that we need to enable the 'stack' option in flex,
which results in a not-easily-suppressed warning from the flex
boilerplate code. This is mildly irritating.
However, this two-token scanning of the /include/ directive also has
some extremely strange edge cases, because there are a variety of
tokens recognized in all scanner states, including INCLUDE. For
example the following strange dts file:
/include/ /dts-v1/;
/ {
/* ... */
};
Will be processed successfully with the /include/ being effectively
ignored: the '/dts-v1/' and ';' are recognized even in INCLUDE state,
then the ';' transitions us to PROPNODENAME state, throwing away
INCLUDE, and the previous state is never popped off the stack. Or
for another example this construct:
foo /include/ = "somefile.dts"
will be parsed as though it were:
foo = /include/ "somefile.dts"
Again, the '=' is scanned without leaving INCLUDE state, then the next
string triggers the include logic.
And finally, we use a different regexp for the string with the
included filename than the normal string regexpt, which is also
potentially weird.
This patch, therefore, cleans up the lexical handling of the /include/
directive. Instead of the INCLUDE state, we instead scan the whole
include directive, both keyword and filename as a single token. This
does mean a bit more complexity in extracting the filename out of
yytext, but I think it's worth it to avoid the strageness described
above. It also means it's no longer possible to put a comment between
the /include/ and the filename, but I'm really not very worried about
breaking files using such a strange construct.
Index: dtc/dtc-lexer.l
===================================================================
--- dtc.orig/dtc-lexer.l 2008-06-26 17:07:40.000000000 +1000
+++ dtc/dtc-lexer.l 2008-06-26 17:07:46.000000000 +1000
@@ -18,7 +18,7 @@
* USA
*/
-%option noyywrap nounput yylineno stack
+%option noyywrap nounput yylineno
%x INCLUDE
%x BYTESTRING
@@ -28,6 +28,10 @@
PROPNODECHAR [a-zA-Z0-9,[EMAIL PROTECTED]
PATHCHAR ({PROPNODECHAR}|[/])
LABEL [a-zA-Z_][a-zA-Z0-9_]*
+STRING \"([^\\"]|\\.)*\"
+WS [[:space:]]
+COMMENT "/*"([^*]|\*+[^*/])*\*+"/"
+LINECOMMENT "//".*\n
%{
#include "dtc.h"
@@ -58,22 +62,19 @@
%}
%%
-<*>"/include/" yy_push_state(INCLUDE);
-
-<INCLUDE>\"[^"\n]*\" {
- yytext[strlen(yytext) - 1] = 0;
- push_input_file(yytext + 1);
- yy_pop_state();
+<*>"/include/"{WS}*{STRING} {
+ char *name = strchr(yytext, '\"') + 1;
+ yytext[yyleng-1] = '\0';
+ push_input_file(name);
}
-
<*><<EOF>> {
if (!pop_input_file()) {
yyterminate();
}
}
-<*>\"([^\\"]|\\.)*\" {
+<*>{STRING} {
yylloc.file = srcpos_file;
yylloc.first_line = yylineno;
DPRINT("String: %s\n", yytext);
@@ -197,16 +198,9 @@
return DT_INCBIN;
}
-<*>[[:space:]]+ /* eat whitespace */
-
-<*>"/*"([^*]|\*+[^*/])*\*+"/" {
- yylloc.file = srcpos_file;
- yylloc.first_line = yylineno;
- DPRINT("Comment: %s\n", yytext);
- /* eat comments */
- }
-
-<*>"//".*\n /* eat line comments */
+<*>{WS}+ /* eat whitespace */
+<*>{COMMENT}+ /* eat C-style comments */
+<*>{LINECOMMENT}+ /* eat C++-style comments */
<*>. {
yylloc.file = srcpos_file;
Index: dtc/convert-dtsv0-lexer.l
===================================================================
--- dtc.orig/convert-dtsv0-lexer.l 2008-06-26 17:07:40.000000000 +1000
+++ dtc/convert-dtsv0-lexer.l 2008-06-26 17:07:46.000000000 +1000
@@ -17,7 +17,7 @@
* USA
*/
-%option noyywrap nounput stack
+%option noyywrap nounput
%x INCLUDE
%x BYTESTRING
@@ -26,6 +26,11 @@
PROPNODECHAR [a-zA-Z0-9,[EMAIL PROTECTED]
PATHCHAR ({PROPNODECHAR}|[/])
LABEL [a-zA-Z_][a-zA-Z0-9_]*
+STRING \"([^\\"]|\\.)*\"
+WS [[:space:]]
+COMMENT "/*"([^*]|\*+[^*/])*\*+"/"
+LINECOMMENT "//".*\n
+GAP ({WS}|{COMMENT}|{LINECOMMENT})*
%{
#include <string.h>
@@ -91,16 +96,7 @@
%}
%%
-<*>"/include/" {
- ECHO;
- yy_push_state(INCLUDE);
- }
-
-<INCLUDE>\"[^"\n]*\" {
- ECHO;
- yy_pop_state();
- }
-
+<*>"/include/"{GAP}{STRING} ECHO;
<*>\"([^\\"]|\\.)*\" ECHO;
@@ -193,11 +189,7 @@
BEGIN(INITIAL);
}
-<*>[[:space:]]+ ECHO;
-
-<*>"/*"([^*]|\*+[^*/])*\*+"/" ECHO;
-
-<*>"//".*\n ECHO;
+<*>{GAP} ECHO;
<*>- { /* Hack to convert old style memreserves */
saw_hyphen = 1;
--
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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