Merge changes for Ctrl-C and Ctrl-D handling in nmcli/readline (bgo #706118)

https://bugzilla.gnome.org/show_bug.cgi?id=706118

cli/src/common.c

@@ -1101,6 +1101,32 @@ nmc_cleanup_readline (void)
 	rl_cleanup_after_signal ();
 }
 
+
+static gboolean nmcli_in_readline = FALSE;
+static pthread_mutex_t readline_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+gboolean
+nmc_get_in_readline (void)
+{
+	gboolean in_readline;
+
+	pthread_mutex_lock (&readline_mutex);
+	in_readline = nmcli_in_readline;
+	pthread_mutex_unlock (&readline_mutex);
+	return in_readline;
+}
+
+void
+nmc_set_in_readline (gboolean in_readline)
+{
+	pthread_mutex_lock (&readline_mutex);
+	nmcli_in_readline = in_readline;
+	pthread_mutex_unlock (&readline_mutex);
+}
+
+/* Global variable defined in nmcli.c */
+extern NmCli nm_cli;
+
 /**
  * nmc_readline:
  * @prompt_fmt: prompt to print (telling user what to enter). It is standard
@@ -1108,6 +1134,9 @@ nmc_cleanup_readline (void)
  * @...: a list of arguments according to the @prompt_fmt format string
  *
  * Wrapper around libreadline's readline() function.
+ * If user pressed Ctrl-C, readline() is called again (if not in editor and
+ * line is empty, nmcli will quit).
+ * If user pressed Ctrl-D on empty line, nmcli will quit.
  *
  * Returns: the user provided string. In case the user entered empty string,
  * this function returns NULL.
@@ -1122,17 +1151,52 @@ nmc_readline (const char *prompt_fmt, ...)
 	prompt = g_strdup_vprintf (prompt_fmt, args);
 	va_end (args);
 
+readline_mark:
+	/* We are in readline -> Ctrl-C should not quit nmcli */
+	nmc_set_in_readline (TRUE);
 	str = readline (prompt);
+	/* We are outside readline -> Ctrl-C should quit nmcli */
+	nmc_set_in_readline (FALSE);
+
+	/* Add string to the history */
+	if (str && *str)
+		add_history (str);
+
+	/*-- React on Ctrl-C and Ctrl-D --*/
+	/* We quit on Ctrl-D when line is empty */
+	if (str == NULL) {
+		/* Send SIGQUIT to itself */
+		nmc_set_sigquit_internal ();
+		kill (getpid (), SIGQUIT);
+		/* Sleep in this thread so that we don't do anything else until exit */
+		for (;;)
+			sleep (3);
+	}
+	/* Ctrl-C */
+	if (nmc_seen_sigint ()) {
+		nmc_clear_sigint ();
+		if (nm_cli.in_editor || *str) {
+			/* In editor, or the line is not empty */
+			/* Call readline again to get new prompt (repeat) */
+			g_free (str);
+			goto readline_mark;
+		} else {
+			/* Not in editor and line is empty */
+			/* Send SIGQUIT to itself */
+			nmc_set_sigquit_internal ();
+			kill (getpid (), SIGQUIT);
+			/* Sleep in this thread so that we don't do anything else until exit */
+			for (;;)
+				sleep (3);
+		}
+	}
+	g_free (prompt);
+
 	/* Return NULL, not empty string */
 	if (str && *str == '\0') {
 		g_free (str);
 		str = NULL;
 	}
-
-	if (str && *str)
-		add_history (str);
-
-	g_free (prompt);
 	return str;
 }
 

cli/src/common.h

@@ -62,5 +62,7 @@ NMConnection *nmc_find_connection (GSList *list,
 void nmc_cleanup_readline (void);
 char *nmc_readline (const char *prompt_fmt, ...) G_GNUC_PRINTF (1, 2);
 char *nmc_rl_gen_func_basic (const char *text, int state, const char **words);
+gboolean nmc_get_in_readline (void);
+void nmc_set_in_readline (gboolean in_readline);
 
 #endif /* NMC_COMMON_H */

cli/src/connections.c

@@ -7982,6 +7982,9 @@ do_connection_edit (NmCli *nmc, int argc, char **argv)
 		editor_init_new_connection (nmc, connection);
 	}
 
+	/* nmcli runs the editor */
+	nmc->in_editor = TRUE;
+
 	printf ("\n");
 	printf (_("===| nmcli interactive connection editor |==="));
 	printf ("\n\n");

cli/src/nmcli.c

@@ -28,6 +28,8 @@
 #include <signal.h>
 #include <pthread.h>
 #include <locale.h>
+#include <readline/readline.h>
+#include <readline/history.h>
 
 #include <glib.h>
 #include <glib/gi18n.h>
@@ -270,6 +272,46 @@ parse_command_line (NmCli *nmc, int argc, char **argv)
 	return nmc->return_value;
 }
 
+static gboolean nmcli_sigint = FALSE;
+static pthread_mutex_t sigint_mutex = PTHREAD_MUTEX_INITIALIZER;
+static gboolean nmcli_sigquit_internal = FALSE;
+
+gboolean
+nmc_seen_sigint (void)
+{
+	gboolean sigint;
+
+	pthread_mutex_lock (&sigint_mutex);
+	sigint = nmcli_sigint;
+	pthread_mutex_unlock (&sigint_mutex);
+	return sigint;
+}
+
+void
+nmc_clear_sigint (void)
+{
+	pthread_mutex_lock (&sigint_mutex);
+	nmcli_sigint = FALSE;
+	pthread_mutex_unlock (&sigint_mutex);
+}
+
+void
+nmc_set_sigquit_internal (void)
+{
+	nmcli_sigquit_internal = TRUE;
+}
+
+static int
+event_hook_for_readline (void)
+{
+	/* Make readline() exit on SIGINT */
+	if (nmc_seen_sigint ()) {
+		rl_echo_signal_char (SIGINT);
+		rl_stuff_char ('\n');
+	}
+	return 0;
+}
+
 void *signal_handling_thread (void *arg);
 /*
  * Thread function waiting for signals and processing them.
@@ -287,10 +329,25 @@ signal_handling_thread (void *arg) {
 
 		switch (signo) {
 		case SIGINT:
+			if (nmc_get_in_readline ()) {
+				/* Don't quit when in readline, only signal we received SIGINT */
+				pthread_mutex_lock (&sigint_mutex);
+				nmcli_sigint = TRUE;
+				pthread_mutex_unlock (&sigint_mutex);
+			} else {
+				/* We can quit nmcli */
+				nmc_cleanup_readline ();
+				printf (_("\nError: nmcli terminated by signal %s (%d)\n"),
+				        strsignal (signo), signo);
+				exit (1);
+			}
+			break;
 		case SIGQUIT:
 		case SIGTERM:
 			nmc_cleanup_readline ();
-			printf (_("\nError: nmcli terminated by signal %d."), signo);
+			if (!nmcli_sigquit_internal)
+				printf (_("\nError: nmcli terminated by signal %s (%d)\n"),
+				        strsignal (signo), signo);
 			exit (1);
 			break;
 		default:
@@ -320,14 +377,14 @@ setup_signals (void)
 	/* Block all signals of interest. */
 	status = pthread_sigmask (SIG_BLOCK, &signal_set, NULL);
 	if (status != 0) {
-		fprintf (stderr, _("Failed to set signal mask: %d"), status);
+		fprintf (stderr, _("Failed to set signal mask: %d\n"), status);
 		return FALSE;
 	}
 
-       /* Create the signal handling thread. */
+	/* Create the signal handling thread. */
 	status = pthread_create (&signal_thread_id, NULL, signal_handling_thread, NULL);
 	if (status != 0) {
-		fprintf (stderr, _("Failed to create signal handling thread: %d"), status);
+		fprintf (stderr, _("Failed to create signal handling thread: %d\n"), status);
 		return FALSE;
 	}
 
@@ -375,6 +432,7 @@ nmc_init (NmCli *nmc)
 	memset (&nmc->print_fields, '\0', sizeof (NmcPrintFields));
 	nmc->nocheck_ver = FALSE;
 	nmc->ask = FALSE;
+	nmc->in_editor = FALSE;
 	nmc->editor_status_line = FALSE;
 	nmc->editor_save_confirmation = TRUE;
 	nmc->editor_prompt_color = NMC_TERM_COLOR_NORMAL;
@@ -431,6 +489,13 @@ main (int argc, char *argv[])
 	g_type_init ();
 #endif
 
+	/* readline init */
+	rl_event_hook = event_hook_for_readline;
+	/* Set 0.01s timeout to mitigate slowness in readline when a broken version is used.
+	 * See https://bugzilla.redhat.com/show_bug.cgi?id=1109946
+	 */
+	rl_set_keyboard_input_timeout (10000);
+
 	nmc_init (&nm_cli);
 	g_idle_add (start, &args_info);
 

cli/src/nmcli.h

@@ -14,7 +14,7 @@
  * with this program; if not, write to the Free Software Foundation, Inc.,
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  *
- * (C) Copyright 2010 - 2012 Red Hat, Inc.
+ * (C) Copyright 2010 - 2014 Red Hat, Inc.
  */
 
 #ifndef NMC_NMCLI_H
@@ -128,6 +128,7 @@ typedef struct _NmCli {
 	NmcPrintFields print_fields;                      /* Structure with field indices to print */
 	gboolean nocheck_ver;                             /* Don't check nmcli and NM versions: option '--nocheck' */
 	gboolean ask;                                     /* Ask for missing parameters: option '--ask' */
+	gboolean in_editor;                               /* Whether running the editor - nmcli con edit' */
 	gboolean editor_status_line;                      /* Whether to display status line in connection editor */
 	gboolean editor_save_confirmation;                /* Whether to ask for confirmation on saving connections with 'autoconnect=yes' */
 	NmcTermColor editor_prompt_color;                 /* Color of prompt in connection editor */
@@ -137,4 +138,9 @@ typedef struct _NmCli {
 #define NMCLI_ERROR (nmcli_error_quark ())
 GQuark nmcli_error_quark (void);
 
+gboolean nmc_seen_sigint (void);
+void     nmc_clear_sigint (void);
+void     nmc_set_sigquit_internal (void);
+
+
 #endif /* NMC_NMCLI_H */