sh: accept fc options grouped behind one '-'

As per Utility Syntax Guidelines, accept both forms: -l -n and -ln.

To do that, anticipate the source string for the next option that will
be parsed by nextopt(). It's not always *argptr, sometimes it is
nextopt_optptr.

To simplify the check for not_fcnumber, slightly modify nextopt() to
always nullify nextopt_optptr in cases where it would have been set
to point to a NUL character.

Reviewed by:	jilles
Differential Revision:	https://reviews.freebsd.org/D35836

bin/sh/histedit.c

@@ -255,7 +255,6 @@ setterm(const char *term)
 int
 histcmd(int argc, char **argv __unused)
 {
-	int ch;
 	const char *editor = NULL;
 	HistEvent he;
 	int lflg = 0, nflg = 0, rflg = 0, sflg = 0;
@@ -277,25 +276,29 @@ histcmd(int argc, char **argv __unused)
 	if (argc == 1)
 		error("missing history argument");
 
-	while (not_fcnumber(*argptr) && (ch = nextopt("e:lnrs")) != '\0')
-		switch ((char)ch) {
-		case 'e':
-			editor = shoptarg;
-			break;
-		case 'l':
-			lflg = 1;
-			break;
-		case 'n':
-			nflg = 1;
-			break;
-		case 'r':
-			rflg = 1;
-			break;
-		case 's':
-			sflg = 1;
-			break;
-		}
-
+	while (not_fcnumber(*argptr))
+		do {
+			switch (nextopt("e:lnrs")) {
+			case 'e':
+				editor = shoptarg;
+				break;
+			case 'l':
+				lflg = 1;
+				break;
+			case 'n':
+				nflg = 1;
+				break;
+			case 'r':
+				rflg = 1;
+				break;
+			case 's':
+				sflg = 1;
+				break;
+			case '\0':
+				goto operands;
+			}
+		} while (nextopt_optptr != NULL);
+operands:
 	savehandler = handler;
 	/*
 	 * If executing...

bin/sh/options.c

@@ -589,6 +589,9 @@ nextopt(const char *optstring)
 		shoptarg = p;
 		p = NULL;
 	}
-	nextopt_optptr = p;
+	if (p != NULL && *p != '\0')
+		nextopt_optptr = p;
+	else
+		nextopt_optptr = NULL;
 	return c;
 }

bin/sh/tests/builtins/Makefile

@@ -94,6 +94,7 @@ ${PACKAGE}FILES+=		exit3.0
 ${PACKAGE}FILES+=		export1.0
 ${PACKAGE}FILES+=		fc1.0
 ${PACKAGE}FILES+=		fc2.0
+${PACKAGE}FILES+=		fc3.0 fc3.0.stdout fc3.0.stderr
 ${PACKAGE}FILES+=		for1.0
 ${PACKAGE}FILES+=		for2.0
 ${PACKAGE}FILES+=		for3.0

bin/sh/tests/builtins/fc3.0

@@ -0,0 +1,9 @@
+export PS1='_ ' # cannot predict whether ran by root or not
+
+echo ': command1
+: command2
+: command3
+: command4
+fc -l -n -1
+fc -ln 2 3
+' | ENV= HISTFILE=/dev/null ${SH} +m -i

bin/sh/tests/builtins/fc3.0.stderr

@@ -0,0 +1 @@
+_ _ _ _ _ _ _ _ 

bin/sh/tests/builtins/fc3.0.stdout

@@ -0,0 +1,3 @@
+: command4
+: command2
+: command3