Add explicit end-of-test marker to DejaGnu unit test protocol

ChangeLog

@@ -1,3 +1,17 @@
+2022-11-26  Jacob Bachmeyer  <jcb@gnu.org>
+
+	* doc/dejagnu.texi (DejaGnu unit test protocol): Add end marker
+	line using "END" to allow detecting tests that exit prematurely.
+	The "Totals:" line was previously used for this purpose, but it
+	does not match the pattern documented as reserved for carrying
+	unit test results and information.
+
+	* lib/dejagnu.exp (host_execute): Remove test for "Totals" line.
+	(host_execute): Add corresponding support for the new line types.
+
+	* dejagnu.h (totals): Add end marker.
+	(TestState::totals): Likewise.
+
 2022-10-04  Jacob Bachmeyer  <jcb@gnu.org>
 
 	PR58065

dejagnu.h

@@ -161,6 +161,7 @@ totals (void)
     printf ("\t#untested:\t\t%d\n", untest);
   if (unresolve)
     printf ("\t#unresolved:\t\t%d\n", unresolve);
+  printf ("\tEND: done\n");
 }
 
 #ifdef __cplusplus
@@ -263,6 +264,7 @@ class TestState {
 	  std::cout << "\t#untested:\t\t" << untest << std::endl;
 	if (unresolve)
 	  std::cout << "\t#unresolved:\t\t" << unresolve << std::endl;
+	std::cout << "\tEND: done" << std::endl;
       }
 
     // This is so this class can be printed in an ostream.

doc/dejagnu.texi

@@ -10,7 +10,7 @@
 
 @copying
 @c man begin COPYRIGHT
-Copyright @copyright{} 1992-2020 Free Software Foundation, Inc.
+Copyright @copyright{} 1992-2020, 2022 Free Software Foundation, Inc.
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -2538,6 +2538,12 @@ This will cause @i{text} to be printed at verbose levels 2 and higher.
 
 These indicate simple test results.
 
+@print{}@t{@ @ @ @ @ @ @ @ END: }@i{text}
+
+This indicates that the test case is complete.  All subsequent output
+from the test is ignored.  A warning is produced if the test case
+closes its output without producing this line.
+
 Note that all output from a unit test program, including the lines
 recognized and interpreted by DejaGnu, appears in the log.
 

lib/dejagnu.exp

@@ -140,18 +140,16 @@ proc host_execute {args} {
 		XFAILED		{ xfail $output }
 		UNTESTED	{ untested $output }
 		UNRESOLVED	{ unresolved $output }
+		END {
+		    expect -re {.+} { exp_continue }
+		    verbose "All done" 2
+		}
 		default {
 		    unresolved "unknown unit test token $expect_out(1,string)"
 		}
 	    }
 	    set timetol 0
-	    exp_continue
-	}
-	-re {^Totals} {
-	    # Flush the stream to allow the child process to finish writing
-	    # logs or other information, instead of sending SIGPIPE.
-	    expect -re {.+} { exp_continue }
-	    verbose "All done" 2
+	    if { $expect_out(1,string) ne "END" } { exp_continue }
 	}
 	-re {^[^\r\n]*([0-9][0-9]:..:..:[^\n]*)\n} {
 	    # No one seems to know why this pattern is here or what it is
@@ -170,6 +168,7 @@ proc host_execute {args} {
 			$executable $arguments"
 	}
 	eof {
+	    warning "Test case did not emit an end marker"
 	}
 	timeout {
 	    warning "Timed out executing test case"