From 11859c310cd6b6fd892337a5ee1d36921e6d08d8 Mon Sep 17 00:00:00 2001
From: Andrew Burgess <andrew.burgess@embecosm.com>
Date: Mon, 9 Apr 2018 00:18:34 +0100
Subject: [PATCH] gdb/testsuite: Handle targets with lots of registers

In gdb.base/maint.exp a test calls 'maint print registers'.  If the
target has lots of registers this may overflow expect's buffers,
causing the test to fail.

After this commit we process the output line at a time until we get back
to the GDB prompt, this should prevent buffer overrun while still
testing that the command works as required.

gdb/testsuite/ChangeLog:

	* gdb.base/maint.exp: Process output from 'maint print registers'
	line at a time.
---
 gdb/testsuite/ChangeLog          |  5 +++++
 gdb/testsuite/gdb.base/maint.exp | 24 ++++++++++++++++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index a66b8cc4173..73c4a2ca6c2 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-05-04  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* gdb.base/maint.exp: Process output from 'maint print registers'
+	line at a time.
+
 2018-05-04  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* lib/mi-support.exp (mi_run_cmd_full): Fix regexp and add a
diff --git a/gdb/testsuite/gdb.base/maint.exp b/gdb/testsuite/gdb.base/maint.exp
index 93221085653..f576cb38402 100644
--- a/gdb/testsuite/gdb.base/maint.exp
+++ b/gdb/testsuite/gdb.base/maint.exp
@@ -62,8 +62,28 @@ gdb_test_no_output "set height 0"
 gdb_file_cmd ${binfile}
 
 # Test for a regression where this command would internal-error if the
-# program wasn't running.
-gdb_test "maint print registers" "Name.*Nr.*Rel.*Offset.*Size.*Type.*"
+# program wasn't running.  If there's a lot of registers then this
+# might overflow expect's buffers, so process the output line at a
+# time.
+set saw_registers 0
+set saw_headers 0
+set test "maint print registers"
+gdb_test_multiple $test $test {
+    -re "\[^\r\n\]+Name\[^\r\n\]+Nr\[^\r\n\]+Rel\[^\r\n\]+Offset\[^\r\n\]+Size\[^\r\n\]+Type\[^\r\n\]+\[\r\n\]+" {
+	set saw_headers 1
+	exp_continue
+    }
+    -re "^\[^\r\n\]+\[0-9\]+\[^\r\n\]+\[0-9\]+\[^\r\n\]+\[0-9\]+\[^\r\n\]+\[0-9\]+\[^\r\n\]+\[\r\n\]+" {
+        set saw_registers 1
+        exp_continue
+    }
+    -re "^\\*\[0-9\]+\[^\r\n\]+\[\r\n\]+" {
+        exp_continue
+    }
+    -re "$gdb_prompt $" {
+        gdb_assert { $saw_registers && $saw_headers } $test
+    }
+}
 
 # Test "mt expand-symtabs" here as it's easier to verify before we
 # run the program.
-- 
2.30.2