sh: Treat unexpected newlines in substitutions as a syntax error.

The old approach was wrong because PS2 was not used and seems unlikely to
parse extensions (ksh93's ${ COMMAND} may well fail to parse).

Exp-run done by: erwin (with some other sh(1) changes)

1 files changed, 4 insertions, 0 deletions

diff --git a/bin/sh/parser.c b/bin/sh/parser.c
index e19a04e..3f3103a 100644
--- a/bin/sh/parser.c
+++ b/bin/sh/parser.c
@@ -1401,6 +1401,8 @@ parsesub: {
 				subtype = VSERROR;
 				if (c == '}')
 					pungetc();
+				else if (c == '\n' || c == PEOF)
+					synerror("Unexpected end of line in substitution");
 				else
 					USTPUTC(c, out);
 			} else {
@@ -1417,6 +1419,8 @@ parsesub: {
 			default:
 				p = strchr(types, c);
 				if (p == NULL) {
+					if (c == '\n' || c == PEOF)
+						synerror("Unexpected end of line in substitution");
 					if (flags == VSNUL)
 						STPUTC(':', out);
 					STPUTC(c, out);