From 1b0e4f54cbe25b9801e97c7430ec21f50a3c7cc2 Mon Sep 17 00:00:00 2001
From: tg <tg@mirbsd.org>
Date: Thu, 14 Jan 2016 22:49:33 +0000
Subject: [PATCH] =?UTF-8?q?permit=20'read=20-A/-a=20arr[idx]'=20as=20long?=
 =?UTF-8?q?=20as=20only=20one=20element=20is=20read;=20fix=20corruption=20?=
 =?UTF-8?q?of=20array=20indic=C4=93s=20with=20this=20construct=20(LP#15333?=
 =?UTF-8?q?96)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 funcs.c | 26 ++++++++++++++++++++------
 sh.h    |  6 ++++--
 var.c   |  6 ++++--
 3 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/funcs.c b/funcs.c
index 07bd026..c20519a 100644
--- a/funcs.c
+++ b/funcs.c
@@ -38,7 +38,7 @@
 #endif
 #endif
 
-__RCSID("$MirOS: src/bin/mksh/funcs.c,v 1.289 2016/01/13 17:20:49 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/funcs.c,v 1.290 2016/01/14 22:49:31 tg Exp $");
 
 #if HAVE_KILLPG
 /*
@@ -1851,13 +1851,15 @@ c_read(const char **wp)
 	enum { LINES, BYTES, UPTO, READALL } readmode = LINES;
 	char delim = '\n';
 	size_t bytesleft = 128, bytesread;
-	struct tbl *vp /* FU gcc */ = NULL, *vq;
+	struct tbl *vp /* FU gcc */ = NULL, *vq = NULL;
 	char *cp, *allocd = NULL, *xp;
 	const char *ccp;
 	XString xs;
 	size_t xsave = 0;
 	mksh_ttyst tios;
 	bool restore_tios = false;
+	/* to catch read -aN2 foo[i] */
+	bool subarray = false;
 #if HAVE_SELECT
 	bool hastimeout = false;
 	struct timeval tv, tvlim;
@@ -2102,6 +2104,7 @@ c_read(const char **wp)
 	XinitN(xs, 128, ATEMP);
 	if (intoarray) {
 		vp = global(*wp);
+		subarray = last_lookup_was_array;
 		if (vp->flag & RDONLY) {
  c_read_splitro:
 			bi_errorf("read-only: %s", *wp);
@@ -2110,10 +2113,10 @@ c_read(const char **wp)
 			afree(cp, ATEMP);
 			goto c_read_out;
 		}
-		/* exporting an array is currently pointless */
-		unset(vp, 1);
 		/* counter for array index */
-		c = 0;
+		c = subarray ? arrayindex(vp) : 0;
+		/* exporting an array is currently pointless */
+		unset(vp, subarray ? 0 : 1);
 	}
 	if (!aschars) {
 		/* skip initial IFS whitespace */
@@ -2215,7 +2218,18 @@ c_read(const char **wp)
  c_read_gotword:
 	Xput(xs, xp, '\0');
 	if (intoarray) {
-		vq = arraysearch(vp, c++);
+		if (subarray) {
+			/* array element passed, accept first read */
+			if (vq) {
+				bi_errorf("nested arrays not yet supported");
+				goto c_read_spliterr;
+			}
+			vq = vp;
+			if (c)
+				/* [0] doesn't */
+				vq->flag |= AINDEX;
+		} else
+			vq = arraysearch(vp, c++);
 	} else {
 		vq = global(*wp);
 		/* must be checked before exporting */
diff --git a/sh.h b/sh.h
index 5d8c0ac..1fb56ca 100644
--- a/sh.h
+++ b/sh.h
@@ -10,7 +10,7 @@
 
 /*-
  * Copyright © 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
- *	       2011, 2012, 2013, 2014, 2015
+ *	       2011, 2012, 2013, 2014, 2015, 2016
  *	mirabilos <m@mirbsd.org>
  *
  * Provided that these terms and disclaimer and all copyright notices
@@ -175,7 +175,7 @@
 #endif
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.753 2016/01/13 17:20:52 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.754 2016/01/14 22:49:32 tg Exp $");
 #endif
 #define MKSH_VERSION "R52 2016/01/13"
 
@@ -1186,6 +1186,8 @@ struct tbl {
 };
 
 EXTERN struct tbl vtemp;
+/* set by global() and local() */
+EXTERN bool last_lookup_was_array;
 
 /* common flag bits */
 #define ALLOC		BIT(0)	/* val.s has been allocated */
diff --git a/var.c b/var.c
index 58551e8..d816eb1 100644
--- a/var.c
+++ b/var.c
@@ -28,7 +28,7 @@
 #include <sys/sysctl.h>
 #endif
 
-__RCSID("$MirOS: src/bin/mksh/var.c,v 1.196 2016/01/14 20:21:39 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/var.c,v 1.197 2016/01/14 22:49:33 tg Exp $");
 
 /*-
  * Variables
@@ -295,6 +295,7 @@ global(const char *n)
 	if (special(vn))
 		vp->flag |= SPECIAL;
  out:
+	last_lookup_was_array = array;
 	if (vn != n)
 		afree(vname.rw, ATEMP);
 	return (vp);
@@ -345,6 +346,7 @@ local(const char *n, bool copy)
 	if (special(vn))
 		vp->flag |= SPECIAL;
  out:
+	last_lookup_was_array = array;
 	if (vn != n)
 		afree(vname.rw, ATEMP);
 	return (vp);
@@ -1486,7 +1488,7 @@ arrayname(const char *str)
 	const char *p;
 	char *rv;
 
-	if ((p = cstrchr(str, '[')) == 0)
+	if (!(p = cstrchr(str, '[')))
 		/* Shouldn't happen, but why worry? */
 		strdupx(rv, str, ATEMP);
 	else