|
|
|
Re: [PATCH 4/4] [MAIN] Optimize dash -c "command" to avoid a fork | |
| [Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] | |
On Thu, Jul 07, 2011 at 12:57:19PM +0800, Herbert Xu wrote:
> On Wed, Jul 06, 2011 at 11:27:53PM -0500, Jonathan Nieder wrote:
> >
> > Will that work? Without the preadateof check, I would worry that
> > passing EV_EXIT to evalstring would break:
> >
> > $ dash -c 'echo one
> > echo two'
> > one
>
> You're right. I'll back this out for now.
OK, what about this patch?
diff --git a/ChangeLog b/ChangeLog
index 7367c33..c457fc8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2011-07-07 Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
+
+ * Optimize dash -c "command" to avoid a fork.
+
2011-04-10 Jonathan Nieder <jrnieder@xxxxxxxxx>
* Remove unused EV_BACKCMD flag.
diff --git a/src/Makefile.am b/src/Makefile.am
index ba68d55..05ed70a 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -33,7 +33,7 @@ dash_LDADD = builtins.o init.o nodes.o signames.o syntax.o
HELPERS = mkinit mksyntax mknodes mksignames
-BUILT_SOURCES = builtins.h nodes.h syntax.h token.h
+BUILT_SOURCES = builtins.h nodes.h syntax.h token.h token_vars.h
CLEANFILES = \
$(BUILT_SOURCES) $(patsubst %.o,%.c,$(dash_LDADD)) \
$(HELPERS) builtins.def
@@ -44,7 +44,7 @@ EXTRA_DIST = \
mktokens mkbuiltins builtins.def.in mkinit.c \
mknodes.c nodetypes nodes.c.pat mksyntax.c mksignames.c
-token.h: mktokens
+token.h token_vars.h: mktokens
sh $^
builtins.def: builtins.def.in $(top_builddir)/config.h
diff --git a/src/eval.c b/src/eval.c
index 86423b4..6e7b932 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -65,10 +65,6 @@
#endif
-/* flags in argument to evaltree */
-#define EV_EXIT 01 /* exit after evaluating tree */
-#define EV_TESTED 02 /* exit status is checked; ignore -e flag */
-
int evalskip; /* set if we are skipping commands */
STATIC int skipcount; /* number of levels to skip */
MKINIT int loopnest; /* current loop nesting level */
@@ -169,7 +165,7 @@ evalstring(char *s, int flags)
status = 0;
while ((n = parsecmd(0)) != NEOF) {
- evaltree(n, flags);
+ evaltree(n, flags & ~(parser_eof() ? 0 : EV_EXIT));
status = exitstatus;
popstackmark(&smark);
if (evalskip)
diff --git a/src/eval.h b/src/eval.h
index ac394e8..4e4de30 100644
--- a/src/eval.h
+++ b/src/eval.h
@@ -46,6 +46,10 @@ struct backcmd { /* result of evalbackcmd */
struct job *jp; /* job structure for command */
};
+/* flags in argument to evaltree */
+#define EV_EXIT 01 /* exit after evaluating tree */
+#define EV_TESTED 02 /* exit status is checked; ignore -e flag */
+
int evalstring(char *, int);
union node; /* BLETCH for ansi C */
void evaltree(union node *, int);
diff --git a/src/main.c b/src/main.c
index b38dc27..af987c6 100644
--- a/src/main.c
+++ b/src/main.c
@@ -171,7 +171,7 @@ state2:
state3:
state = 4;
if (minusc)
- evalstring(minusc, 0);
+ evalstring(minusc, sflag ? 0 : EV_EXIT);
if (sflag || minusc == NULL) {
state4: /* XXX ??? - why isn't this before the "if" statement */
diff --git a/src/mktokens b/src/mktokens
index 7c873af..cd52241 100644
--- a/src/mktokens
+++ b/src/mktokens
@@ -71,13 +71,16 @@ TEND 1 "}"
nl=`wc -l /tmp/ka$$`
exec > token.h
awk '{print "#define " $1 " " NR-1}' /tmp/ka$$
+
+exec > token_vars.h
+
echo '
/* Array indicating which tokens mark the end of a list */
-const char tokendlist[] = {'
+static const char tokendlist[] = {'
awk '{print "\t" $2 ","}' /tmp/ka$$
echo '};
-const char *const tokname[] = {'
+static const char *const tokname[] = {'
sed -e 's/"/\\"/g' \
-e 's/[^ ]*[ ][ ]*[^ ]*[ ][ ]*\(.*\)/ "\1",/' \
/tmp/ka$$
@@ -85,7 +88,7 @@ echo '};
'
sed 's/"//g' /tmp/ka$$ | awk '
/TNOT/{print "#define KWDOFFSET " NR-1; print "";
- print "STATIC const char *const parsekwd[] = {"}
+ print "static const char *const parsekwd[] = {"}
/TNOT/,/neverfound/{if (last) print " \"" last "\","; last = $3}
END{print " \"" last "\"\n};"}'
diff --git a/src/parser.c b/src/parser.c
index 528d005..6de2762 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -64,7 +64,7 @@
*/
/* values returned by readtoken */
-#include "token.h"
+#include "token_vars.h"
@@ -86,7 +86,7 @@ struct heredoc *heredoclist; /* list of here documents to read */
int doprompt; /* if set, prompt the user */
int needprompt; /* true if interactive and at start of line */
int lasttoken; /* last token read */
-MKINIT int tokpushback; /* last token pushed back */
+int tokpushback; /* last token pushed back */
char *wordtext; /* text of last word returned by readtoken */
int checkkwd;
struct nodelist *backquotelist;
@@ -210,6 +210,7 @@ list(int nlflag)
parseheredoc();
else
pungetc(); /* push back EOF on input */
+ tokpushback++;
return n1;
default:
if (nlflag == 1)
diff --git a/src/parser.h b/src/parser.h
index e6caed6..2875cce 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -34,6 +34,8 @@
* @(#)parser.h 8.3 (Berkeley) 5/4/95
*/
+#include "token.h"
+
/* control characters in argument strings */
#define CTL_FIRST -127 /* first 'special' character */
#define CTLESC -127 /* escape next character */
@@ -73,6 +75,7 @@
* must be distinct from NULL, so we use the address of a variable that
* happens to be handy.
*/
+extern int lasttoken;
extern int tokpushback;
#define NEOF ((union node *)&tokpushback)
extern int whichprompt; /* 1 == PS1, 2 == PS2 */
@@ -91,3 +94,8 @@ goodname(const char *p)
{
return !*endofname(p);
}
+
+static inline int parser_eof(void)
+{
+ return tokpushback && lasttoken == TEOF;
+}
Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
To unsubscribe from this list: send the line "unsubscribe dash" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html