ncurses 6.0 - patch 20161224

[ncurses.git] / progs / tty_settings.c

diff --git a/progs/tty_settings.c b/progs/tty_settings.c
new file mode 100644 (file)
index 0000000..93d9e2a
--- /dev/null
+++ b/progs/tty_settings.c
@@ -0,0 +1,109 @@
+/****************************************************************************
+ * Copyright (c) 2016 Free Software Foundation, Inc.                        *
+ *                                                                          *
+ * Permission is hereby granted, free of charge, to any person obtaining a  *
+ * copy of this software and associated documentation files (the            *
+ * "Software"), to deal in the Software without restriction, including      *
+ * without limitation the rights to use, copy, modify, merge, publish,      *
+ * distribute, distribute with modifications, sublicense, and/or sell       *
+ * copies of the Software, and to permit persons to whom the Software is    *
+ * furnished to do so, subject to the following conditions:                 *
+ *                                                                          *
+ * The above copyright notice and this permission notice shall be included  *
+ * in all copies or substantial portions of the Software.                   *
+ *                                                                          *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
+ * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
+ * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
+ *                                                                          *
+ * Except as contained in this notice, the name(s) of the above copyright   *
+ * holders shall not be used in advertising or otherwise to promote the     *
+ * sale, use or other dealings in this Software without prior written       *
+ * authorization.                                                           *
+ ****************************************************************************/
+
+/****************************************************************************
+ *  Author: Thomas E. Dickey                                                *
+ ****************************************************************************/
+
+#define USE_LIBTINFO
+#include <tty_settings.h>
+
+#include <fcntl.h>
+
+MODULE_ID("$Id: tty_settings.c,v 1.2 2016/12/24 19:31:11 tom Exp $")
+
+static int my_fd;
+static TTY original_settings;
+static bool can_restore = FALSE;
+
+static void
+exit_error(void)
+{
+    restore_tty_settings();
+    (void) fprintf(stderr, "\n");
+    ExitProgram(EXIT_FAILURE);
+    /* NOTREACHED */
+}
+
+static void
+failed(const char *msg)
+{
+    char temp[BUFSIZ];
+
+    _nc_STRCPY(temp, _nc_progname, sizeof(temp));
+    _nc_STRCAT(temp, ": ", sizeof(temp));
+    _nc_STRNCAT(temp, msg, sizeof(temp), sizeof(temp) - strlen(temp) - 2);
+    perror(temp);
+    exit_error();
+    /* NOTREACHED */
+}
+
+static bool
+get_tty_settings(int fd, TTY * tty_settings)
+{
+    bool success = TRUE;
+    my_fd = fd;
+    if (fd < 0 || GET_TTY(my_fd, tty_settings) < 0) {
+       success = FALSE;
+    }
+    return success;
+}
+
+/*
+ * Open a file descriptor on the current terminal, to obtain its settings.
+ * stderr is less likely to be redirected than stdout; try that first.
+ */
+int
+save_tty_settings(TTY * tty_settings)
+{
+    if (!get_tty_settings(STDERR_FILENO, tty_settings) &&
+       !get_tty_settings(STDOUT_FILENO, tty_settings) &&
+       !get_tty_settings(STDIN_FILENO, tty_settings) &&
+       !get_tty_settings(open("/dev/tty", O_RDWR), tty_settings)) {
+       failed("terminal attributes");
+    }
+    can_restore = TRUE;
+    original_settings = *tty_settings;
+    return my_fd;
+}
+
+void
+restore_tty_settings(void)
+{
+    if (can_restore)
+       SET_TTY(my_fd, &original_settings);
+}
+
+/* Set the modes if they've changed. */
+void
+update_tty_settings(TTY * old_settings, TTY * new_settings)
+{
+    if (memcmp(new_settings, old_settings, sizeof(TTY))) {
+       SET_TTY(my_fd, new_settings);
+    }
+}