Fix the case where the recursion detection isn't reset when the command is

interrupted.

Lots of back and forth with anton@
OK jca@, tb@, anton@

3 files changed, 21 insertions, 9 deletions

diff --git a/bin/ksh/history.c b/bin/ksh/history.c
index 67735c90964..1448f8abc58 100644
--- a/bin/ksh/history.c
+++ b/bin/ksh/history.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: history.c,v 1.80 2018/01/15 22:30:38 jca Exp $	*/
+/*	$OpenBSD: history.c,v 1.81 2018/11/20 07:02:23 martijn Exp $	*/
 
 /*
  * command history
@@ -48,6 +48,8 @@ static uint32_t	line_co;
 
 static struct stat last_sb;
 
+static volatile sig_atomic_t	c_fc_depth;
+
 int
 c_fc(char **wp)
 {
@@ -58,9 +60,8 @@ c_fc(char **wp)
 	int optc, ret;
 	char *first = NULL, *last = NULL;
 	char **hfirst, **hlast, **hp;
-	static int depth;
 
-	if (depth != 0) {
+	if (c_fc_depth != 0) {
 		bi_errorf("history function called recursively");
 		return 1;
 	}
@@ -146,9 +147,9 @@ c_fc(char **wp)
 		    hist_get_newest(false);
 		if (!hp)
 			return 1;
-		depth++;
+		c_fc_depth++;
 		ret = hist_replace(hp, pat, rep, gflag);
-		depth--;
+		c_fc_reset();
 		return ret;
 	}
 
@@ -268,13 +269,22 @@ c_fc(char **wp)
 		shf_close(shf);
 		*xp = '\0';
 		strip_nuls(Xstring(xs, xp), Xlength(xs, xp));
-		depth++;
+		c_fc_depth++;
 		ret = hist_execute(Xstring(xs, xp));
-		depth--;
+		c_fc_reset();
 		return ret;
 	}
 }
 
+/* Reset the c_fc depth counter.
+ * Made available for when an fc call is interrupted.
+ */
+void
+c_fc_reset(void)
+{
+	c_fc_depth = 0;
+}
+
 /* Save cmd in history, execute cmd (cmd gets trashed) */
 static int
 hist_execute(char *cmd)
diff --git a/bin/ksh/main.c b/bin/ksh/main.c
index 63508d4dc84..e74c12f3a37 100644
--- a/bin/ksh/main.c
+++ b/bin/ksh/main.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: main.c,v 1.95 2018/11/17 18:14:58 deraadt Exp $	*/
+/*	$OpenBSD: main.c,v 1.96 2018/11/20 07:02:23 martijn Exp $	*/
 
 /*
  * startup, main loop, environments and error handling
@@ -557,6 +557,7 @@ shell(Source *volatile s, volatile int toplevel)
 		case LERROR:
 		case LSHELL:
 			if (interactive) {
+				c_fc_reset();
 				if (i == LINTR)
 					shellf("\n");
 				/* Reset any eof that was read as part of a
diff --git a/bin/ksh/sh.h b/bin/ksh/sh.h
index cf2c6c3a595..2efa875bb80 100644
--- a/bin/ksh/sh.h
+++ b/bin/ksh/sh.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sh.h,v 1.73 2018/05/18 13:25:20 benno Exp $	*/
+/*	$OpenBSD: sh.h,v 1.74 2018/11/20 07:02:23 martijn Exp $	*/
 
 /*
  * Public Domain Bourne/Korn shell
@@ -449,6 +449,7 @@ void	hist_init(Source *);
 void	hist_finish(void);
 void	histsave(int, const char *, int);
 int	c_fc(char **);
+void	c_fc_reset(void);
 void	sethistcontrol(const char *);
 void	sethistsize(int);
 void	sethistfile(const char *);