Hi!
Personally I don't like this mode, I think it will be much better just
to add condition to {beginning,end}-of-buffer to push mark only if it's
not pushed already.
The only thing I didn't implement is region highlighting because I am
still not familiar with mg's code.
Here's the diff:
Index: basic.c
===================================================================
RCS file: /cvs/src/usr.bin/mg/basic.c,v
retrieving revision 1.48
diff -u -p -u -p -r1.48 basic.c
--- basic.c 3 Jun 2019 16:26:30 -0000 1.48
+++ basic.c 8 Jun 2019 14:21:17 -0000
@@ -116,6 +116,23 @@ forwchar(int f, int n)
return (TRUE);
}
+static int transient_mark = 1;
+static int mark_active = 1;
+
+/*
+ * Toggle transient marking
+ */
+int
+transientmarktoggle(int f, int n)
+{
+ if (f & FFARG)
+ transient_mark = mark_active = n > 0;
+ else
+ transient_mark = mark_active = !transient_mark;
+ ewprintf("Transient marking %sabled", transient_mark ? "en" : "dis");
+ return (TRUE);
+}
+
/*
* Go to the beginning of the buffer. Setting WFFULL is conservative,
* but almost always the case. A universal argument of higher than 9
@@ -124,7 +141,8 @@ forwchar(int f, int n)
int
gotobob(int f, int n)
{
- (void) setmark(f, n);
+ if (!(mark_active && curwp->w_markp))
+ (void) setmark(f, n);
curwp->w_dotp = bfirstlp(curbp);
curwp->w_doto = 0;
curwp->w_rflag |= WFFULL;
@@ -150,7 +168,8 @@ gotoeob(int f, int n)
int ln;
struct line *lp;
- (void) setmark(f, n);
+ if (!(mark_active && curwp->w_markp))
+ (void) setmark(f, n);
curwp->w_dotp = blastlp(curbp);
curwp->w_doto = llength(curwp->w_dotp);
curwp->w_dotline = curwp->w_bufp->b_lines;
@@ -478,8 +497,15 @@ isetmark(void)
int
setmark(int f, int n)
{
- isetmark();
- ewprintf("Mark set");
+ if (curwp->w_markp == curwp->w_dotp &&
+ curwp->w_marko == curwp->w_doto &&
+ curwp->w_markline == curwp->w_dotline) {
+ mark_active = !transient_mark | !(transient_mark & mark_active);
+ ewprintf("Mark %sactivated", mark_active ? "" : "de");
+ } else {
+ isetmark();
+ ewprintf("Mark set");
+ }
return (TRUE);
}
@@ -491,6 +517,7 @@ clearmark(int f, int n)
if (!curwp->w_markp)
return (FALSE);
+ mark_active = transient_mark;
curwp->w_markp = NULL;
curwp->w_marko = 0;
curwp->w_markline = 0;
Index: def.h
===================================================================
RCS file: /cvs/src/usr.bin/mg/def.h,v
retrieving revision 1.157
diff -u -p -u -p -r1.157 def.h
--- def.h 13 Dec 2018 14:59:16 -0000 1.157
+++ def.h 8 Jun 2019 14:21:17 -0000
@@ -508,6 +508,7 @@ int gotobol(int, int);
int backchar(int, int);
int gotoeol(int, int);
int forwchar(int, int);
+int transientmarktoggle(int, int);
int gotobob(int, int);
int gotoeob(int, int);
int forwline(int, int);
Index: funmap.c
===================================================================
RCS file: /cvs/src/usr.bin/mg/funmap.c,v
retrieving revision 1.55
diff -u -p -u -p -r1.55 funmap.c
--- funmap.c 13 Dec 2018 14:59:16 -0000 1.55
+++ funmap.c 8 Jun 2019 14:21:18 -0000
@@ -202,6 +202,7 @@ static struct funmap functnames[] = {
{poptobuffer, "switch-to-buffer-other-window",},
{togglereadonly, "toggle-read-only" },
{togglereadonlyall, "toggle-read-only-all" },
+ {transientmarktoggle, "transient-mark-mode"},
{twiddle, "transpose-chars",},
{transposepara, "transpose-paragraphs",},
{transposeword, "transpose-words",},
Index: mg.1
===================================================================
RCS file: /cvs/src/usr.bin/mg/mg.1,v
retrieving revision 1.114
diff -u -p -u -p -r1.114 mg.1
--- mg.1 6 Jun 2019 18:17:34 -0000 1.114
+++ mg.1 8 Jun 2019 14:21:18 -0000
@@ -1,7 +1,7 @@
.\" $OpenBSD: mg.1,v 1.114 2019/06/06 18:17:34 jmc Exp $
.\" This file is in the public domain.
.\"
-.Dd $Mdocdate: June 6 2019 $
+.Dd $Mdocdate: June 8 2019 $
.Dt MG 1
.Os
.Sh NAME
@@ -408,6 +408,8 @@ Move cursor to the top of the buffer.
A numeric argument
.Va n
will move n/10th of the way from the top.
+Set mark at previous position if transient marking is disabled
+and mark is not set.
.It beginning-of-line
Move cursor to the beginning of the line.
.It blink-and-insert
@@ -532,6 +534,8 @@ Move cursor to the end of the buffer.
A numeric argument
.Va n
will move n/10th of the way from the end.
+Set mark at previous position if transient marking is disabled
+and mark is not set.
.It end-of-line
Move cursor to the end of the line.
.It enlarge-window
@@ -864,6 +868,8 @@ Prompt the user for a fill column.
Used by auto-fill-mode.
.It set-mark-command
Sets the mark in the current window to the current dot location.
+Repetitive invokation in sequence temporarily turns transient
+marking on/off.
.It set-prefix-string
Sets the prefix string to be used by the 'prefix-region' command.
.It shell-command
@@ -894,6 +900,8 @@ Toggle the read-only flag on the current
Toggle the read-only flag on all non-ephemeral buffers.
A simple toggle that switches a global read-only flag either on
or off.
+.It transient-mark-mode
+Toggle transient marking where active region is highlighted.
.It transpose-chars
Transpose the two characters in front of and under dot,
then move forward one character.
Index: region.c
===================================================================
RCS file: /cvs/src/usr.bin/mg/region.c,v
retrieving revision 1.37
diff -u -p -u -p -r1.37 region.c
--- region.c 9 Sep 2016 06:05:51 -0000 1.37
+++ region.c 8 Jun 2019 14:21:18 -0000
@@ -405,6 +405,7 @@ markbuffer(int f, int n)
{
if (gotoeob(f,n) == FALSE)
return (FALSE);
+ (void) clearmark(f, n);
if (gotobob(f,n) == FALSE)
return (FALSE);
return (TRUE);
