[PATCH] parser: Print CTLBACKQ early in parsesub

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

On Thu, Jan 05, 2023 at 02:42:04PM +0100, наб wrote:
>
> I think this means we also need to turn the USTPUTC() into STPUTC(),
> since the previous code explicitly over-accounted for it in growstackto().

Good catch.  However, we can easily get rid of it by moving the
USTPUTC to the top:

---8<---
As we are allowed to perform 4 USTPUTC's we can save a growstackstr
call by adding the CTLBACKQ before we save the string.

Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

diff --git a/src/parser.c b/src/parser.c
index f5f76d5..299c260 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -1360,6 +1360,7 @@ parsebackq: {
 	struct heredoc *saveheredoclist;
 	int uninitialized_var(saveprompt);
 
+	USTPUTC(CTLBACKQ, out);
 	str = stackblock();
 	savelen = out - (char *)stackblock();
 	grabstackblock(savelen);
@@ -1443,7 +1444,6 @@ done:
 	if (oldstyle)
 		tokpushback = 0;
 	out = stnputs(str, savelen, stackblock());
-	STPUTC(CTLBACKQ, out);
 	if (oldstyle)
 		goto parsebackq_oldreturn;
 	else
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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