script: add --echo

It some cases it makes sense to disable ECHO flag also when script
used in pipe. This new option allows to keep full control in user's
hands.

Signed-off-by: Karel Zak <kzak@redhat.com>

include/pty-session.h

@@ -76,14 +76,14 @@ struct ul_pty {
 	struct timeval	next_callback_time;
 
 	unsigned int isterm:1,		/* is stdin terminal? */
-		     keep_slave_echo:1;	/* keep ECHO on stdin */
+		     slave_echo:1;	/* keep ECHO on stdin */
 };
 
 void ul_pty_init_debug(int mask);
 struct ul_pty *ul_new_pty(int is_stdin_tty);
 void ul_free_pty(struct ul_pty *pty);
 
-void ul_pty_keep_slave_echo(struct ul_pty *pty, int enable);
+void ul_pty_slave_echo(struct ul_pty *pty, int enable);
 int ul_pty_get_delivered_signal(struct ul_pty *pty);
 
 void ul_pty_set_callback_data(struct ul_pty *pty, void *data);

lib/pty-session.c

@@ -71,10 +71,10 @@ void ul_free_pty(struct ul_pty *pty)
 	free(pty);
 }
 
-void ul_pty_keep_slave_echo(struct ul_pty *pty, int enable)
+void ul_pty_slave_echo(struct ul_pty *pty, int enable)
 {
 	assert(pty);
-	pty->keep_slave_echo = enable ? 1 : 0;
+	pty->slave_echo = enable ? 1 : 0;
 }
 
 int ul_pty_get_delivered_signal(struct ul_pty *pty)
@@ -172,20 +172,28 @@ int ul_pty_setup(struct ul_pty *pty)
 		/* set the current terminal to raw mode; pty_cleanup() reverses this change on exit */
 		slave_attrs = pty->stdin_attrs;
 		cfmakeraw(&slave_attrs);
-		slave_attrs.c_lflag &= ~ECHO;
+
+		if (pty->slave_echo)
+			slave_attrs.c_lflag |= ECHO;
+		else
+			slave_attrs.c_lflag &= ~ECHO;
+
 		tcsetattr(STDIN_FILENO, TCSANOW, &slave_attrs);
 	} else {
 	        DBG(SETUP, ul_debugobj(pty, "create for non-terminal"));
-		rc = openpty(&pty->master, &pty->slave, NULL, NULL, NULL);
 
-		if (!rc) {
-			tcgetattr(pty->slave, &slave_attrs);
-			if (!pty->keep_slave_echo) {
-				slave_attrs.c_lflag &= ~ECHO;
-				tcsetattr(pty->slave, TCSANOW, &slave_attrs);
-			}
-		} else
+		rc = openpty(&pty->master, &pty->slave, NULL, NULL, NULL);
+		if (rc)
 			goto done;
+
+		tcgetattr(pty->slave, &slave_attrs);
+
+		if (pty->slave_echo)
+			slave_attrs.c_lflag |= ECHO;
+		else
+			slave_attrs.c_lflag &= ~ECHO;
+
+		tcsetattr(pty->slave, TCSANOW, &slave_attrs);
 	}
 
 	sigfillset(&ourset);

term-utils/script.1

@@ -88,6 +88,13 @@ rather than an interactive shell.  This makes it easy for a script to capture
 the output of a program that behaves differently when its stdout is not a
 tty.
 .TP
+\fB\-E\fR, \fB\-\-echo\fR \fIwhen\fR
+This option controls the ECHO flag for pseudoterminal within the session. The
+supported modes are always, never, or auto. The default is "auto" -- in this
+case, ECHO is disabled if the current standard input is a terminal to avoid
+double-echo, and enabled if standard input is not terminal (for example pipe:
+"echo date | script") to avoid missing input in the session log.
+.TP
 \fB\-e\fR, \fB\-\-return\fR
 Return the exit code of the child process.  Uses the same format as bash
 termination on signal termination exit code is 128+n.  The exit code of

term-utils/script.c

@@ -208,6 +208,7 @@ static void __attribute__((__noreturn__)) usage(void)
 	fputs(_(" -e, --return                  return exit code of the child process\n"), out);
 	fputs(_(" -f, --flush                   run flush after each write\n"), out);
 	fputs(_("     --force                   use output file even when it is a link\n"), out);
+	fputs(_(" -E, --echo <when>             echo input (auto, always or never)\n"), out);
 	fputs(_(" -o, --output-limit <size>     terminate if output files exceed size\n"), out);
 	fputs(_(" -q, --quiet                   be quiet\n"), out);
 
@@ -720,7 +721,7 @@ int main(int argc, char **argv)
 		.in  = { .ident = 'I' },
 	};
 	struct ul_pty_callbacks *cb;
-	int ch, format = 0, caught_signal = 0, rc = 0;
+	int ch, format = 0, caught_signal = 0, rc = 0, echo = 0;
 	const char *outfile = NULL, *infile = NULL;
 	const char *timingfile = NULL, *shell = NULL, *command = NULL;
 
@@ -729,6 +730,7 @@ int main(int argc, char **argv)
 	static const struct option longopts[] = {
 		{"append", no_argument, NULL, 'a'},
 		{"command", required_argument, NULL, 'c'},
+		{"echo", required_argument, NULL, 'E'},
 		{"return", no_argument, NULL, 'e'},
 		{"flush", no_argument, NULL, 'f'},
 		{"force", no_argument, NULL, FORCE_OPTION,},
@@ -765,7 +767,14 @@ int main(int argc, char **argv)
 	script_init_debug();
 	ON_DBG(PTY, ul_pty_init_debug(0xFFFF));
 
-	while ((ch = getopt_long(argc, argv, "aB:c:efI:O:o:qm:T:t::Vh", longopts, NULL)) != -1) {
+	/* The default is to keep ECHO flag when stdin is not terminal. We need
+	 * it to make stdin (in case of "echo foo | script") log-able and
+	 * visiable on terminal, and for backward compatibility.
+	 */
+	ctl.isterm = isatty(STDIN_FILENO);
+	echo = ctl.isterm ? 0 : 1;
+
+	while ((ch = getopt_long(argc, argv, "aB:c:eE:fI:O:o:qm:T:t::Vh", longopts, NULL)) != -1) {
 
 		err_exclusive_options(ch, longopts, excl, excl_st);
 
@@ -776,6 +785,16 @@ int main(int argc, char **argv)
 		case 'c':
 			command = optarg;
 			break;
+		case 'E':
+			if (strcmp(optarg, "auto") == 0)
+				; /* keep default */
+			else if (strcmp(optarg, "never") == 0)
+				echo = 0;
+			else if (strcmp(optarg, "always") == 0)
+				echo = 1;
+			else
+				errx(EXIT_FAILURE, _("unssuported echo mode: '%s'"), optarg);
+			break;
 		case 'e':
 			ctl.rc_wanted = 1;
 			break;
@@ -870,17 +889,11 @@ int main(int argc, char **argv)
 	if (!shell)
 		shell = _PATH_BSHELL;
 
-	ctl.isterm = isatty(STDIN_FILENO);
 	ctl.pty = ul_new_pty(ctl.isterm);
 	if (!ctl.pty)
 		err(EXIT_FAILURE, "failed to allocate PTY handler");
 
-	if (!ctl.isterm)
-		/* We keep ECHO flag for 'echo "date" | script' otherwise the
-		 * input is no visible (output is completely comtroled by
-		 * shell/command, we do not write anything there).
-		 */
-		ul_pty_keep_slave_echo(ctl.pty, 1);
+	ul_pty_slave_echo(ctl.pty, echo);
 
 	ul_pty_set_callback_data(ctl.pty, (void *) &ctl);
 	cb = ul_pty_get_callbacks(ctl.pty);

term-utils/scriptlive.c

@@ -291,7 +291,7 @@ main(int argc, char *argv[])
 
 	if (!isatty(STDIN_FILENO))
 		/* We keep ECHO flag for compatibility with script(1) */
-		ul_pty_keep_slave_echo(ss.pty, 1);
+		ul_pty_slave_echo(ss.pty, 1);
 
 	if (ul_pty_setup(ss.pty))
 		err(EXIT_FAILURE, _("failed to create pseudo-terminal"));