Fix vty being closed while waiting on '--more--' prompt.

The vty_half_close() did not properly take care of the CLI state
when in "cli_more_wait" state.

This fix tests for cli_more_wait state in vty_half_close() and
explicitly exits that state.  (Instead of letting the state be
cleared implicitly, which didn't quite tidy up quickly enough.)

5 files changed, 51 insertions, 13 deletions

diff --git a/lib/command.h b/lib/command.h
index 1c66c083..ba7c4bb2 100644
--- a/lib/command.h
+++ b/lib/command.h
@@ -393,4 +393,8 @@ extern char *argv_concat (const char* const* argv, int argc, int shift);
 /* struct host global, ick */
 extern struct host host;
 
+#ifdef QDEBUG
+extern const char *debug_banner ;
+#endif
+
 #endif /* _ZEBRA_COMMAND_H */
diff --git a/lib/vty.c b/lib/vty.c
index 749b2155..51bf4a5a 100644
--- a/lib/vty.c
+++ b/lib/vty.c
@@ -23,7 +23,7 @@
 
 #include "zebra.h"
 #include <stdbool.h>
-#include "version.h"
+#include "lib/version.h"
 
 #include "vty_io.h"
 #include "vty.h"
diff --git a/lib/vty_cli.c b/lib/vty_cli.c
index 461d511e..fab266b1 100644
--- a/lib/vty_cli.c
+++ b/lib/vty_cli.c
@@ -689,7 +689,7 @@ uty_cli_cmd_complete(vty_io vio, enum cmd_return_code ret)
  * Outputs the new prompt line.
  */
 extern void
-uty_cli_go_more_wait(vty_io vio)
+uty_cli_enter_more_wait(vty_io vio)
 {
   VTY_ASSERT_LOCKED() ;
 
@@ -705,6 +705,40 @@ uty_cli_go_more_wait(vty_io vio)
 } ;
 
 /*------------------------------------------------------------------------------
+ * Exit the "--more--" CLI.
+ *
+ * Wipes the "--more--" prompt.
+ *
+ * This is used when the user responds to the prompt.
+ *
+ * It is also used when the vty is "half-closed".  In this case, it is (just)
+ * possible that the '--more--' prompt is yet to be completely written away,
+ * so:
+ *
+ *   * assert that is either: !vio->cli_blocked (most of the time it will)
+ *                        or: !vio_fifo_empty(&vio->cli_obuf)
+ *
+ *   * note that can wipe the prompt even though it hasn't been fully
+ *     written away yet.  (The effect is to append the wipe action to the
+ *     cli_obuf !)
+ */
+extern void
+uty_cli_exit_more_wait(vty_io vio)
+{
+  VTY_ASSERT_LOCKED() ;
+
+  assert( (!vio->cli_blocked || !vio_fifo_empty(&vio->cli_obuf))
+         && !vio->cmd_out_enabled && vio->cli_more_wait) ;
+
+  uty_cli_wipe(vio, 0) ;        /* wipe the prompt ('--more--')
+                                   before changing the CLI state        */
+
+  vio->cli_blocked      = 1 ;   /* back to blocked waiting for output   */
+  vio->cli_more_wait    = 0 ;   /* exit more_wait                       */
+  vio->cmd_out_enabled  = 1 ;   /* re-enable output                     */
+} ;
+
+/*------------------------------------------------------------------------------
  * Handle the "--more--" state.
  *
  * Deals with the first stage if cli_blocked.
@@ -792,11 +826,7 @@ uty_cli_more_wait(vty_io vio)
    * Return write_ready to tidy up the screen and, unless cleared, write
    * some more.
    */
-  uty_cli_wipe(vio, 0) ;
-
-  vio->cli_blocked      = 1 ;   /* back to blocked waiting for output   */
-  vio->cli_more_wait    = 0 ;   /* exit more_wait                       */
-  vio->cmd_out_enabled  = 1 ;   /* re-enable output                     */
+  uty_cli_exit_more_wait(vio) ;
 
   return now_ready ;
 } ;
@@ -1082,11 +1112,11 @@ uty_cli_wipe(vty_io vio, int len)
       b += vio->cl.cp ;
     } ;
 
-  /* Stuff ahead of the current position if any ahead of new len        */
+  /* Wipe anything ahead of the current position and ahead of new len   */
   if ((a + b) > len)
     uty_cli_out_wipe_n(vio, +a) ;
 
-  /* Stuff behind current position, but ahead of new len                */
+  /* Wipe anything behind current position, but ahead of new len        */
   if (b > len)
     {
       uty_cli_out_wipe_n(vio, -(b - len)) ;
diff --git a/lib/vty_cli.h b/lib/vty_cli.h
index 5bf682ac..f532616a 100644
--- a/lib/vty_cli.h
+++ b/lib/vty_cli.h
@@ -35,7 +35,9 @@ extern enum vty_readiness uty_cli(vty_io vio) ;
 extern keystroke_callback uty_cli_iac_callback ;
 
 extern void uty_cli_hist_add (vty_io vio, const char* cmd_line) ;
-extern void uty_cli_go_more_wait(vty_io vio) ;
+extern void uty_cli_enter_more_wait(vty_io vio) ;
+extern void uty_cli_exit_more_wait(vty_io vio) ;
+
 extern void uty_free_host_name(void) ;
 extern void uty_check_host_name(void) ;
 
diff --git a/lib/vty_io.c b/lib/vty_io.c
index c4b4f528..9fd9ff2a 100644
--- a/lib/vty_io.c
+++ b/lib/vty_io.c
@@ -716,11 +716,13 @@ uty_half_close (vty_io vio, const char* reason)
 
   /* Turn off "--more--" so that all output clears without interruption.
    *
-   * Note that if is waiting for "--more--", then shutting the read side
-   * causes it to be readable, but EOF -- so that will flush through.
+   * If is sitting on a "--more--" prompt, then exit the wait_more CLI.
    */
   vio->cli_more_enabled = 0 ;
 
+  if (vio->cli_more_wait)
+    uty_cli_exit_more_wait(vio) ;
+
   /* If a command is not in progress, enable output, which will clear
    * the output buffer if there is anything there, plus any close reason,
    * and then close.
@@ -1696,7 +1698,7 @@ uty_write_fifo_lc(vty_io vio, vio_fifo vf, vio_line_control lc)
    * cleared.
    */
   if (lc->paused && vio->cli_more_enabled)
-    uty_cli_go_more_wait(vio) ;
+    uty_cli_enter_more_wait(vio) ;
 
   return 1 ;                    /* FIFO or line control, not empty      */
 } ;