Add a 'batch' mode to mg via the '-b' command line option which will

initialise a pty, run the specified file of mg commands and then exit.

This is to facilitate mg fitting into the OpenBSD regress test
framework and be able to run via a cron job.

5 files changed, 74 insertions, 11 deletions

diff --git a/usr.bin/mg/def.h b/usr.bin/mg/def.h
index e3cc9e7cfe4..7b7d90088ec 100644
--- a/usr.bin/mg/def.h
+++ b/usr.bin/mg/def.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: def.h,v 1.168 2021/03/01 10:51:14 lum Exp $	*/
+/*	$OpenBSD: def.h,v 1.169 2021/03/20 09:00:49 lum Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -750,6 +750,7 @@ extern int		 doaudiblebell;
 extern int		 dovisiblebell;
 extern int		 dblspace;
 extern int		 allbro;
+extern int		 batch;
 extern char	 	 cinfo[];
 extern char		*keystrings[];
 extern char		 pat[NPAT];
diff --git a/usr.bin/mg/main.c b/usr.bin/mg/main.c
index d0d94e365ad..ac2175adb28 100644
--- a/usr.bin/mg/main.c
+++ b/usr.bin/mg/main.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: main.c,v 1.88 2021/02/23 08:10:51 lum Exp $	*/
+/*	$OpenBSD: main.c,v 1.89 2021/03/20 09:00:49 lum Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -14,7 +14,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <termios.h>
 #include <unistd.h>
+#include <util.h>
 
 #include "def.h"
 #include "kbd.h"
@@ -33,6 +35,7 @@ int		 doaudiblebell;			/* audible bell toggle	*/
 int		 dovisiblebell;			/* visible bell toggle	*/
 int		 dblspace;			/* sentence end #spaces	*/
 int		 allbro;			/* all buffs read-only	*/
+int		 batch;				/* for regress tests	*/
 struct buffer	*curbp;				/* current buffer	*/
 struct buffer	*bheadp;			/* BUFFER list head	*/
 struct mgwin	*curwp;				/* current window	*/
@@ -40,6 +43,7 @@ struct mgwin	*wheadp;			/* MGWIN listhead	*/
 char		 pat[NPAT];			/* pattern		*/
 
 static void	 edinit(struct buffer *);
+static void	 pty_init(void);
 static __dead void usage(void);
 
 extern char	*__progname;
@@ -48,8 +52,8 @@ extern void     closetags(void);
 static __dead void
 usage()
 {
-	fprintf(stderr, "usage: %s [-nR] [-f mode] [-u file] [+number] "
-	    "[file ...]\n",
+	fprintf(stderr, "usage: %s [-nR] [-b file] [-f mode] [-u file] "
+	    "[+number] [file ...]\n",
 	    __progname);
 	exit(1);
 }
@@ -58,6 +62,7 @@ int
 main(int argc, char **argv)
 {
 	char		*cp, *conffile = NULL, *init_fcn_name = NULL;
+	char		*batchfile = NULL;
 	PF		 init_fcn = NULL;
 	int	 	 o, i, nfiles;
 	int	  	 nobackups = 0;
@@ -67,8 +72,12 @@ main(int argc, char **argv)
 	    NULL) == -1)
 		err(1, "pledge");
 
-	while ((o = getopt(argc, argv, "nRf:u:")) != -1)
+	while ((o = getopt(argc, argv, "nRb:f:u:")) != -1)
 		switch (o) {
+		case 'b':
+			batch = 1;
+			batchfile = optarg;
+			break;
 		case 'R':
 			allbro = 1;
 			break;
@@ -87,6 +96,22 @@ main(int argc, char **argv)
 		default:
 			usage();
 		}
+
+	if (batch && (conffile != NULL)) {
+                fprintf(stderr, "%s: -b and -u are mutually exclusive.\n",
+                    __progname);
+                exit(1);
+	}
+	if (batch) {
+		pty_init();
+		conffile = batchfile;
+	}
+	if (conffile != NULL && access(conffile, R_OK) != 0) {
+                fprintf(stderr, "%s: Problem with file: %s\n", __progname,
+		    conffile);
+                exit(1);
+	}
+
 	argc -= optind;
 	argv += optind;
 
@@ -136,6 +161,9 @@ main(int argc, char **argv)
 	if ((cp = startupfile(NULL, conffile)) != NULL)
 		(void)load(cp);
 
+	if (batch)
+		return (0);
+
 	/*
 	 * Now ensure any default buffer modes from the startup file are
 	 * given to any files opened when parsing the startup file.
@@ -252,6 +280,26 @@ edinit(struct buffer *bp)
 }
 
 /*
+ * Create pty for batch mode.
+ */
+static void
+pty_init(void)
+{
+	struct winsize	 ws;
+	int		 master;
+	int		 slave;
+
+	memset(&ws, 0, sizeof(ws));
+	ws.ws_col = 80,
+	ws.ws_row = 24;
+	
+	openpty(&master, &slave, NULL, NULL, &ws);
+	login_tty(slave);
+
+	return;
+}
+
+/*
  * Quit command.  If an argument, always quit.  Otherwise confirm if a buffer
  * has been changed and not written out.  Normally bound to "C-x C-c".
  */
diff --git a/usr.bin/mg/mg.1 b/usr.bin/mg/mg.1
index e5b4c4a7af6..29066df6ea7 100644
--- a/usr.bin/mg/mg.1
+++ b/usr.bin/mg/mg.1
@@ -1,7 +1,7 @@
-.\"	$OpenBSD: mg.1,v 1.120 2021/02/23 18:45:33 lum Exp $
+.\"	$OpenBSD: mg.1,v 1.121 2021/03/20 09:00:49 lum Exp $
 .\" This file is in the public domain.
 .\"
-.Dd $Mdocdate: February 23 2021 $
+.Dd $Mdocdate: March 20 2021 $
 .Dt MG 1
 .Os
 .Sh NAME
@@ -10,6 +10,7 @@
 .Sh SYNOPSIS
 .Nm mg
 .Op Fl nR
+.Op Fl b Ar file
 .Op Fl f Ar mode
 .Op Fl u Ar file
 .Op + Ns Ar number
@@ -35,6 +36,12 @@ sign and the number).
 If a negative number is specified, the line number counts
 backwards from the end of the file i.e. +-1 will be the last
 line of the file, +-2 will be second last, and so on.
+.It Fl b Ar file
+Turn on batch mode and execute the
+.Nm
+commands found in the specified
+.Ar file
+and then terminate.
 .It Fl f Ar mode
 Run the mode command for all buffers created from
 arguments on the command line, including the
diff --git a/usr.bin/mg/tty.c b/usr.bin/mg/tty.c
index 75237af2475..6522a240232 100644
--- a/usr.bin/mg/tty.c
+++ b/usr.bin/mg/tty.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tty.c,v 1.38 2021/03/01 10:51:14 lum Exp $	*/
+/*	$OpenBSD: tty.c,v 1.39 2021/03/20 09:00:49 lum Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -34,6 +34,7 @@
 #include <signal.h>
 #include <stdio.h>
 #include <term.h>
+#include <unistd.h>
 
 #include "def.h"
 
@@ -64,9 +65,15 @@ winchhandler(int sig)
 void
 ttinit(void)
 {
+	char *tty;
 	int errret;
 
-	if (setupterm(NULL, 1, &errret))
+	if (batch == 1)
+		tty = "pty";
+	else
+		tty = NULL;
+
+	if (setupterm(tty, STDOUT_FILENO, &errret))
 		panic("Terminal setup failed");
 
 	signal(SIGWINCH, winchhandler);
diff --git a/usr.bin/mg/ttyio.c b/usr.bin/mg/ttyio.c
index 57c03e40f0f..54ddd8efe15 100644
--- a/usr.bin/mg/ttyio.c
+++ b/usr.bin/mg/ttyio.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ttyio.c,v 1.39 2021/03/01 10:51:14 lum Exp $	*/
+/*	$OpenBSD: ttyio.c,v 1.40 2021/03/20 09:00:49 lum Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -140,7 +140,7 @@ ttflush(void)
 	ssize_t	 written;
 	char	*buf = obuf;
 
-	if (nobuf == 0)
+	if (nobuf == 0 || batch == 1)
 		return;
 
 	while ((written = write(fileno(stdout), buf, nobuf)) != nobuf) {