* event-loop.c (struct callback_event): New struct.

[external/binutils.git] / gdb / gdbserver / remote-utils.c

diff --git a/gdb/gdbserver/remote-utils.c b/gdb/gdbserver/remote-utils.c
index 2bbce67..6410659 100644 (file)
--- a/gdb/gdbserver/remote-utils.c
+++ b/gdb/gdbserver/remote-utils.c
@@ -80,7 +80,19 @@ typedef int socklen_t;
 # define INVALID_DESCRIPTOR -1
 #endif
 
+/* Extra value for readchar_callback.  */
+enum {
+  /* The callback is currently not scheduled.  */
+  NOT_SCHEDULED = -1
+};
+
+/* Status of the readchar callback.
+   Either NOT_SCHEDULED or the callback id.  */
+static int readchar_callback = NOT_SCHEDULED;
+
 static int readchar (void);
+static void reset_readchar (void);
+static void reschedule (void);
 
 /* A cache entry for a successfully looked-up symbol.  */
 struct sym_cache
@@ -341,6 +353,8 @@ remote_close (void)
   close (remote_desc);
 #endif
   remote_desc = INVALID_DESCRIPTOR;
+
+  reset_readchar ();
 }
 
 /* Convert hex digit A to a number.  */
@@ -926,33 +940,83 @@ initialize_async_io (void)
   unblock_async_io ();
 }
 
+/* Internal buffer used by readchar.
+   These are global to readchar because reschedule_remote needs to be
+   able to tell whether the buffer is empty.  */
+
+static unsigned char readchar_buf[BUFSIZ];
+static int readchar_bufcnt = 0;
+static unsigned char *readchar_bufp;
+
 /* Returns next char from remote GDB.  -1 if error.  */
 
 static int
 readchar (void)
 {
-  static unsigned char buf[BUFSIZ];
-  static int bufcnt = 0;
-  static unsigned char *bufp;
+  int ch;
 
-  if (bufcnt-- > 0)
-    return *bufp++;
+  if (readchar_bufcnt == 0)
+    {
+      readchar_bufcnt = read (remote_desc, readchar_buf, sizeof (readchar_buf));
 
-  bufcnt = read (remote_desc, buf, sizeof (buf));
+      if (readchar_bufcnt <= 0)
+       {
+         if (readchar_bufcnt == 0)
+           fprintf (stderr, "readchar: Got EOF\n");
+         else
+           perror ("readchar");
 
-  if (bufcnt <= 0)
-    {
-      if (bufcnt == 0)
-       fprintf (stderr, "readchar: Got EOF\n");
-      else
-       perror ("readchar");
+         return -1;
+       }
 
-      return -1;
+      readchar_bufp = readchar_buf;
     }
 
-  bufp = buf;
-  bufcnt--;
-  return *bufp++;
+  readchar_bufcnt--;
+  ch = *readchar_bufp++;
+  reschedule ();
+  return ch;
+}
+
+/* Reset the readchar state machine.  */
+
+static void
+reset_readchar (void)
+{
+  readchar_bufcnt = 0;
+  if (readchar_callback != NOT_SCHEDULED)
+    {
+      delete_callback_event (readchar_callback);
+      readchar_callback = NOT_SCHEDULED;
+    }
+}
+
+/* Process remaining data in readchar_buf.  */
+
+static int
+process_remaining (void *context)
+{
+  int res;
+
+  /* This is a one-shot event.  */
+  readchar_callback = NOT_SCHEDULED;
+
+  if (readchar_bufcnt > 0)
+    res = handle_serial_event (0, NULL);
+  else
+    res = 0;
+
+  return res;
+}
+
+/* If there is still data in the buffer, queue another event to process it,
+   we can't sleep in select yet.  */
+
+static void
+reschedule (void)
+{
+  if (readchar_bufcnt > 0 && readchar_callback == NOT_SCHEDULED)
+    readchar_callback = append_callback_event (process_remaining, NULL);
 }
 
 /* Read a packet from the remote machine, with error checking,