+/*
+ * Copyright (c) 2003 Nikodemus Siivola
+ *
+ * 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, 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 AUTHORS OR 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.
+ */
+
+#include <unistd.h>
+#include <termios.h>
+#include <stdlib.h>
+
+typedef struct {
+ struct termios *attr;
+ void *next;
+}
+state_t;
+
+state_t * stack = NULL;
+
+int
+save_term (void)
+{
+ state_t * state = malloc (sizeof (state_t));
+ struct termios * attr = malloc (sizeof (struct termios));
+ if (! (state && attr))
+ return 0;
+
+ tcgetattr (STDIN_FILENO, attr);
+
+ state->attr = attr;
+ state->next = stack;
+ stack = state;
+
+ return 1;
+}
+
+void
+restore_term (void)
+{
+ state_t * tmp = stack;
+ if (!stack) return;
+
+ tcsetattr (STDIN_FILENO, TCSANOW, stack->attr);
+ stack = stack->next;
+
+ free (tmp->attr);
+ free (tmp);
+}
+
+int
+no_echo (void)
+{
+ struct termios attr;
+ if (! (isatty (STDIN_FILENO) && save_term ()))
+ return 0;
+
+ tcgetattr (STDIN_FILENO, &attr);
+ attr.c_lflag &= ~ECHO;
+ tcsetattr (STDIN_FILENO, TCSAFLUSH, &attr);
+
+ return 1;
+}