RFA: add testsuite function for answering internal error questions

[Jim Blandy <jimb@redhat.com>]

[re-posting: bad changelog entry.]

2002-11-06  Jim Blandy  <jimb@redhat.com>

	* lib/gdb.exp (gdb_internal_error_regexp): New variable.
	(gdb_internal_error_resync): New procedure.
        (gdb_test): If the command results in an internal error,
        answer GDB's questions until we get back to a prompt.

Index: gdb/testsuite/lib/gdb.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/lib/gdb.exp,v
retrieving revision 1.27
diff -c -r1.27 gdb.exp
*** gdb/testsuite/lib/gdb.exp	18 Sep 2002 15:34:10 -0000	1.27
--- gdb/testsuite/lib/gdb.exp	6 Nov 2002 20:21:58 -0000
***************
*** 370,375 ****
--- 370,425 ----
  }
  
  
+ # A regular expression matching the output GDB produces when it
+ # reports an internal error.
+ set gdb_internal_error_regexp ".*A problem internal to GDB has been detected"
+ 
+ 
+ # gdb_internal_error_resync TESTNAME
+ #
+ # Answer the questions GDB asks after it reports an internal error
+ # until we get back to a GDB prompt, as part of the test named
+ # TESTNAME.  Decline to quit the debugging session, and decline to
+ # create a core file.
+ #
+ # This procedure just answers whatever questions come up until it sees
+ # a GDB prompt; it doesn't require you to have matched the input up to
+ # any specific point.  However, it only answers questions it sees in
+ # the output itself, so if you've matched a question, you had better
+ # answer it yourself before calling this.
+ #
+ # The variable `gdb_internal_error_regexp' is set up to match the
+ # internal error message, but none of the questions that follow it, so
+ # you can write code like this:
+ # 
+ # gdb_expect {
+ #     ...
+ #     -re $gdb_internal_error_regexp {
+ #         gdb_internal_error_resync "$message (internal error)"
+ #     }
+ #     ...
+ # }
+ proc gdb_internal_error_resync {testname} {
+     global gdb_prompt
+ 
+     gdb_expect {
+         -re "Quit this debugging session\\? \\(y or n\\) $" {
+             send_gdb "n\n"
+             exp_continue
+         }
+         -re "Create a core file of GDB\\? \\(y or n\\) $" {
+             send_gdb "n\n"
+             exp_continue
+         }
+         -re "$gdb_prompt $" {
+             # We're resynchronized.
+         }
+         timeout {
+             fail "$testname (internal error resync timeout)"
+         }
+     }
+ }
+   
  
  # gdb_test COMMAND PATTERN MESSAGE QUESTION RESPONSE
  # Send a command to gdb; test the result.
***************
*** 395,400 ****
--- 445,451 ----
      global verbose
      global gdb_prompt
      global GDB
+     global gdb_internal_error_regexp
      upvar timeout timeout
  
      if [llength $args]>2 then {
***************
*** 477,482 ****
--- 528,537 ----
  	}
      }
      gdb_expect $tmt {
+          -re $gdb_internal_error_regexp {
+              fail "$message"
+              gdb_internal_error_resync "$message (internal error)"
+          }
  	 -re "\\*\\*\\* DOSEXIT code.*" {
  	     if { $message != "" } {
  		 fail "$message";