Fix pasting of long (>BUFSIZ) lines in csh with filec enabled. NUL-terminating

the input buffer instructs csh that the buffer contains a complete command. This
is wrong and should only happen when buffer is not full, otherwise more data has
to be read in order form a complete command.

While here, do not print the prompt again when the input exceeds the input
buffer and while inserting a line continuation (backslash).

4 files changed, 22 insertions, 9 deletions

diff --git a/bin/csh/csh.c b/bin/csh/csh.c
index 517f11413b6..5df655ade5d 100644
--- a/bin/csh/csh.c
+++ b/bin/csh/csh.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: csh.c,v 1.40 2017/07/26 19:15:09 anton Exp $	*/
+/*	$OpenBSD: csh.c,v 1.41 2017/08/30 06:42:21 anton Exp $	*/
 /*	$NetBSD: csh.c,v 1.14 1995/04/29 23:21:28 mycroft Exp $	*/
 
 /*-
@@ -1008,7 +1008,8 @@ process(bool catch)
 	     * read fresh stuff. Otherwise, we are rereading input and don't
 	     * need or want to prompt.
 	     */
-	    if (!filec && aret == F_SEEK && fseekp == feobp)
+	    needprompt = aret == F_SEEK && fseekp == feobp;
+	    if (!filec && needprompt)
 		printprompt();
 	    (void) fflush(cshout);
 	}
diff --git a/bin/csh/csh.h b/bin/csh/csh.h
index 601b7bb9772..b830d810681 100644
--- a/bin/csh/csh.h
+++ b/bin/csh/csh.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: csh.h,v 1.29 2017/07/22 09:37:21 anton Exp $	*/
+/*	$OpenBSD: csh.h,v 1.30 2017/08/30 06:42:21 anton Exp $	*/
 /*	$NetBSD: csh.h,v 1.9 1995/03/21 09:02:40 cgd Exp $	*/
 
 /*-
@@ -108,6 +108,7 @@ bool    timflg;			/* Time the next waited for command */
 bool    havhash;		/* path hashing is available */
 
 bool    filec;			/* doing filename expansion */
+bool    needprompt;		/* print prompt, used by filec */
 
 /*
  * Global i/o info
diff --git a/bin/csh/file.c b/bin/csh/file.c
index 5d130ebf260..11c6a38a11d 100644
--- a/bin/csh/file.c
+++ b/bin/csh/file.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: file.c,v 1.33 2017/07/26 19:20:51 anton Exp $	*/
+/*	$OpenBSD: file.c,v 1.34 2017/08/30 06:42:21 anton Exp $	*/
 /*	$NetBSD: file.c,v 1.11 1996/11/08 19:34:37 christos Exp $	*/
 
 /*-
@@ -779,8 +779,11 @@ tenex(Char *inputline, int inputline_size)
 	cl.size = sizeof(buf);
 	if (tio->c_lflag & ALTWERASE)
 		cl.flags |= CL_ALTWERASE;
-	cl.flags |= CL_PROMPT;
-	cl_flush(&cl);	/* print prompt */
+	if (needprompt) {
+		needprompt = 0;
+		cl.flags |= CL_PROMPT;
+		cl_flush(&cl);
+	}
 
 	for (;;) {
 		if ((c = cl_getc(&cl)) == 0)
@@ -799,7 +802,14 @@ tenex(Char *inputline, int inputline_size)
 
 	for (i = 0; i < cl.len; i++)
 		inputline[i] = cl.buf[i];
-	inputline[i] = '\0';
+	/*
+	 * NUL-terminating the buffer implies that it contains a complete
+	 * command ready to be executed. Therefore, don't terminate if the
+	 * buffer is full since more characters must be read in order to form a
+	 * complete command.
+	 */
+	if (i < sizeof(buf))
+		inputline[i] = '\0';
 
 	return cl.len;
 }
diff --git a/bin/csh/func.c b/bin/csh/func.c
index 4ce579d09a6..0cdcf62251b 100644
--- a/bin/csh/func.c
+++ b/bin/csh/func.c
@@ -1,4 +1,4 @@
-/*    $OpenBSD: func.c,v 1.34 2017/07/26 19:15:09 anton Exp $       */
+/*    $OpenBSD: func.c,v 1.35 2017/08/30 06:42:21 anton Exp $       */
 /*    $NetBSD: func.c,v 1.11 1996/02/09 02:28:29 christos Exp $       */
 
 /*-
@@ -589,7 +589,8 @@ search(int type, int level, Char *goal)
 	bseek(&a);
     }
     do {
-	if (intty && !filec && fseekp == feobp && aret == F_SEEK)
+	needprompt = intty && fseekp == feobp && aret == F_SEEK;
+	if (!filec && needprompt)
 	    (void) fprintf(cshout, "? "), (void) fflush(cshout);
 	aword[0] = 0;
 	(void) getword(aword);