From patchwork Tue Jan 1 22:45:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Burgess X-Patchwork-Id: 30927 Received: (qmail 122684 invoked by alias); 1 Jan 2019 22:45:26 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 122577 invoked by uid 89); 1 Jan 2019 22:45:20 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.2 spammy=Better, fills, supplied, answered X-HELO: mail-wm1-f47.google.com Received: from mail-wm1-f47.google.com (HELO mail-wm1-f47.google.com) (209.85.128.47) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 01 Jan 2019 22:45:18 +0000 Received: by mail-wm1-f47.google.com with SMTP id y185so31766389wmd.1 for ; Tue, 01 Jan 2019 14:45:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=embecosm.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :in-reply-to:references; bh=I4IyhubibHME6pf8kxBUHAMWMC+HsT6TIjh87wHapX4=; b=KGr396WNrgWwsoOLLYj4G86G5GZYKCO24YlPrpkR8JVR8mkHa0OgrvZwLMtrWcgXJL vDRf/9r19duU92UPEY2FyUVOhIlqBD+4HVAJsoXPGaTel3FkzLRsJRBpfqMwZWbuvh83 5h7fSEgtcli2+Tz1BabFQ7zFDNxqoVORffSzs4H5Ridd8c321bqycYggtMJ8AlGKNSLs Yz3zJBYD9HI1Uv/2mFsftz9MJlCPxgi8naLeD/KtKLTrhozsfysHQ2uh4Hx6DOGUxMIC d2ljsPJ0jl1dyLTDBSFGvstFnB+XW8OQBFLQDLMwQdeR1HsqprbPzfZOyayGokP+JvtF LGdA== Return-Path: Received: from localhost (host86-172-198-47.range86-172.btcentralplus.com. [86.172.198.47]) by smtp.gmail.com with ESMTPSA id l14sm105970214wrp.55.2019.01.01.14.45.14 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 01 Jan 2019 14:45:15 -0800 (PST) From: Andrew Burgess To: gdb-patches@sourceware.org Cc: Andrew Burgess Subject: [PATCH 1/6] gdb/testsuite: Better detection of auto-response at y/n prompts Date: Tue, 1 Jan 2019 22:45:01 +0000 Message-Id: <9f15f4ed7b5f22de0b0606fe363bce6689b11a60.1546382416.git.andrew.burgess@embecosm.com> In-Reply-To: References: In-Reply-To: References: X-IsSubscribed: yes I noticed that when running this test: make check-gdb RUNTESTFLAGS="--target_board=native-gdbserver gdb.mi/mi-break.exp" I would occasionally see some UNRESOLVED test results like this: (gdb) PASS: gdb.mi/mi-break.exp: mi-mode=separate: breakpoint at main Expecting: ^(kill[ ]+)?(.*[ ]+[(]gdb[)] [ ]*) kill &"kill\n" ~"Kill the program being debugged? (y or n) [answered Y; input not from terminal]\n" =thread-group-exited,id="i1" ERROR: Got interactive prompt. UNRESOLVED: gdb.mi/mi-break.exp: mi-mode=separate: The problem appears to be that the expect buffer fills up to include the '(y or n)' prompt without including the following lines. The pattern supplied by the outer test script is looking for the following lines. As the following lines are not present then expect matches on the interactive prompt case rather than the case for the user supplied pattern. The problem with this is that we are not really at an interactive prompt, GDB is providing an answer for us and then moving on. When I examine a successful run of the test the output from GDB is identical, the only difference is where expect happens to buffer the output from GDB. This patch introduces a second check inside the 'y or n' prompt case, which gives expect a chance to refill its buffers and catches the 'answered Y; input ...' text. This second check is on a short 1 second timeout, I'm currently assuming that the auto-answer text will either already be in expect, or is waiting to be read in. If after 1 second the auto-answer text is not seen then we assume that GDB really is waiting at an interactive prompt. With this patch in place I can now leave the following loop running indefinitely, where before it would fail usually after ~10 iterations. while make check-gdb RUNTESTFLAGS="--target_board=native-gdbserver gdb.mi/mi-break.exp"; \ do /bin/true; \ done gdb/testsuite/ChangeLog: * lib/mi-support.exp (mi_gdb_test): When detecting a 'y or n' interactive prompt, look for the auto-answer before declaring a fail. --- gdb/testsuite/ChangeLog | 6 ++++++ gdb/testsuite/lib/mi-support.exp | 21 ++++++++++++++++++--- 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/gdb/testsuite/lib/mi-support.exp b/gdb/testsuite/lib/mi-support.exp index d193592a843..48ea45d62c7 100644 --- a/gdb/testsuite/lib/mi-support.exp +++ b/gdb/testsuite/lib/mi-support.exp @@ -834,9 +834,24 @@ proc mi_gdb_test { args } { fail "$message" } -re "\\(y or n\\) " { - send_gdb "n\n" - perror "Got interactive prompt." - fail "$message" + # If the expect buffer just happens to fill up to the 'y + # or n' prompt then we can end up in this case, even + # though GDB will automatically provide a response for us. + # We give expect another chance here to look for the auto + # answer text before declaring a fail. + set auto_response_seen 0 + gdb_expect 1 { + -re ".answered Y; input not from terminal." { + set auto_response_seen 1 + } + } + if { ! $auto_response_seen } { + send_gdb "n\n" + perror "Got interactive prompt." + fail "$message" + } else { + exp_continue + } } eof { perror "Process no longer exists"