Restore terminal on SIGCONT

From: Petr Baudis <pasky@ucw.cz>

New bash versions won't restore the tty settings after the process is
backgrounded and then foregrounded back. This makes mpg123 do so itself
in a SIGCONT handler.
---

 src/term.c |   38 +++++++++++++++++++++++++++++---------
 1 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/src/term.c b/src/term.c
index d0fcc01..e37804e 100644
--- a/src/term.c
+++ b/src/term.c
@@ -26,30 +26,50 @@ extern int buffer_pid;
 static int term_enable = 0;
 static struct termios old_tio;
 
+void term_sigcont(int sig);
+
+/* This must call only functions safe inside a signal handler. */
+int term_setup(struct termios *pattern)
+{
+  struct termios tio = *pattern;
+
+  signal(SIGCONT, term_sigcont);
+
+  tio.c_lflag &= ~(ICANON|ECHO); 
+  tio.c_cc[VMIN] = 1;
+  tio.c_cc[VTIME] = 0;
+  return tcsetattr(0,TCSANOW,&tio);
+}
+
+void term_sigcont(int sig)
+{
+  term_enable = 0;
+
+  if (term_setup(&old_tio) < 0) {
+    fprintf(stderr,"Can't set terminal attributes\n");
+    return;
+  }
+
+  term_enable = 1;
+}
+
 /* initialze terminal */
 void term_init(void)
 {
-  struct termios tio;
   debug("term_init");
 
   term_enable = 0;
 
-  if(tcgetattr(0,&tio) < 0) {
+  if(tcgetattr(0,&old_tio) < 0) {
     fprintf(stderr,"Can't get terminal attributes\n");
     return;
   }
-  old_tio=tio;
-  tio.c_lflag &= ~(ICANON|ECHO); 
-  tio.c_cc[VMIN] = 1;
-  tio.c_cc[VTIME] = 0;
-
-  if(tcsetattr(0,TCSANOW,&tio) < 0) {
+  if(term_setup(&old_tio) < 0) {
     fprintf(stderr,"Can't set terminal attributes\n");
     return;
   }
 
   term_enable = 1;
- 
 }
 
 static long term_handle_input(struct frame *,int);