From 041210b22813850a5c9720ef8b6f134ec0f50e00 Mon Sep 17 00:00:00 2001
From: Renaud Fivet <renaud.fivet@gmail.com>
Date: Fri, 26 Aug 2022 11:16:45 +0800
Subject: [PATCH] Use memmove instead of memcpy for overlapping memory area.
 (reproducible on OpenBSD).

---
 README.md | 6 +++---
 defines.h | 2 +-
 exec.c    | 6 ++----
 line.c    | 2 +-
 pklock.c  | 4 ----
 posix.c   | 8 ++++++--
 6 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/README.md b/README.md
index d9aa711..b6bc439 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # README #
 
-µEMACS (ue) on Cygwin/Linux/NetBSD, based on uEmacs/PK (em) from [kernel.org](
-https://git.kernel.org/pub/scm/editors/uemacs/uemacs.git/).
+µEMACS (ue) on Cygwin/MSYS2/Linux/NetBSD/OpenBSD, based on uEmacs/PK (em)
+from [kernel.org](https://git.kernel.org/pub/scm/editors/uemacs/uemacs.git/).
 
 ### Changes compare to uEmacs/PK ###
 
@@ -26,6 +26,6 @@ https://git.kernel.org/pub/scm/editors/uemacs/uemacs.git/).
 
 ### How to build ###
 
-* dependencies: gcc, gmake, ncurses-devel.
+* dependencies: (gcc || clang) && gmake && ncurses-devel.
 
 * make
diff --git a/defines.h b/defines.h
index dce2d05..c222c75 100644
--- a/defines.h
+++ b/defines.h
@@ -4,7 +4,7 @@
 
 #if __unix__ || (defined(__APPLE__) && defined(__MACH__))
 # define UNIX 1
-# if __NetBSD__ || (defined(__APPLE__) && defined(__MACH__))
+# if __NetBSD__ || __OpenBSD__ || (defined(__APPLE__) && defined(__MACH__))
 #  define BSD 1
 #  define POSIX 1
 # elif __linux__
diff --git a/exec.c b/exec.c
index b6577d4..c8bf6cc 100644
--- a/exec.c
+++ b/exec.c
@@ -557,9 +557,7 @@ static int dobuf( buffer_p bp) {
 	/* remove leading spaces */
 		if( eline != lp->l_text) {
 			int size = lp->l_used = eol - eline ;
-			if( size)
-				memcpy( lp->l_text, eline, size) ;
-
+			memmove( lp->l_text, eline, size) ;
 			eline = lp->l_text ;
 			eol = &lp->l_text[ size] ;
 		}
@@ -595,7 +593,7 @@ static int dobuf( buffer_p bp) {
 		/* turn line into a string */
 			int size = lp->l_used - 6 ;
 			if( size)
-				memcpy( lp->l_text, &eline[ 6], size) ;
+				memmove( lp->l_text, &eline[ 6], size) ;
 
 			eline = lp->l_text ;
 			eline[ size] = 0 ;
diff --git a/line.c b/line.c
index 593a87b..29b5af5 100644
--- a/line.c
+++ b/line.c
@@ -455,7 +455,7 @@ boolean lnewline( void) {
 
     memcpy( lp2->l_text, lp1->l_text, doto) ;
     lp1->l_used -= doto ;
-	memcpy( lp1->l_text, &lp1->l_text[ doto], lp1->l_used) ;
+	memmove( lp1->l_text, &lp1->l_text[ doto], lp1->l_used) ;
     lp2->l_fp = lp1 ;
     lp2->l_bp = lp1->l_bp ;
     lp1->l_bp = lp2 ;
diff --git a/pklock.c b/pklock.c
index 3354946..f86afec 100644
--- a/pklock.c
+++ b/pklock.c
@@ -12,11 +12,7 @@
 #include <unistd.h>
 #include <stdio.h>
 #include <fcntl.h>
-#ifdef SVR4
 #include <string.h>
-#else
-#include <strings.h>
-#endif
 #include <errno.h>
 
 #include "util.h"
diff --git a/posix.c b/posix.c
index fdf649d..8182920 100644
--- a/posix.c
+++ b/posix.c
@@ -31,8 +31,12 @@ int ttcol = -1 ;		/* Column location of HW cursor */
 
 /* Define missing macroes for BSD and CYGWIN environment */
 #if BSD
-#define OLCUC 0000002
-#define XCASE 0000004
+# ifndef OLCUC
+#  define OLCUC 0000002
+# endif
+# ifndef XCASE
+#  define XCASE 0000004
+# endif
 #endif
 
 #ifdef __CYGWIN__			/* gcc predefined (see cpp -dM) */