From patchwork Thu Jan 16 15:24:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Marchi X-Patchwork-Id: 37408 Received: (qmail 9997 invoked by alias); 16 Jan 2020 15:24:41 -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 9924 invoked by uid 89); 16 Jan 2020 15:24:34 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-18.0 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.1 spammy=pts X-HELO: simark.ca Received: from simark.ca (HELO simark.ca) (158.69.221.121) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 16 Jan 2020 15:24:22 +0000 Received: from [10.0.0.11] (unknown [192.222.164.54]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id 28DCA1E47D; Thu, 16 Jan 2020 10:24:09 -0500 (EST) Subject: Re: [PATCH 2/4] gdb: remove use of iterate_over_inferiors in mi/mi-interp.c To: "Aktemur, Tankut Baris" , Simon Marchi , "gdb-patches@sourceware.org" References: <20200115191222.28208-1-simon.marchi@efficios.com> <20200115191222.28208-3-simon.marchi@efficios.com> From: Simon Marchi Message-ID: <80e26b82-476e-f898-3b97-4d923c2eb6e7@simark.ca> Date: Thu, 16 Jan 2020 10:24:08 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.1 MIME-Version: 1.0 In-Reply-To: On 2020-01-16 4:01 a.m., Aktemur, Tankut Baris wrote: >> @@ -140,8 +138,22 @@ mi_interp::init (bool top_level) >> /* The initial inferior is created before this function is >> called, so we need to report it explicitly. Use iteration in >> case future version of GDB creates more than one inferior >> - up-front. */ >> - iterate_over_inferiors (report_initial_inferior, mi); >> + up-front. >> + >> + This function is called from mi_interpreter_init, and since > > There is an 8-spaces/tab issue above. And also, the comment piece "This > function is called from mi_interpreter_init, and" seems obsolete now. Thanks for spotting these. That made me realize there are many issues with that comment. - The part about not being able to use mi_inferior_added because top_level_interpreter_data is not set is stale. That was true before the interps were made into C++ classes. Back then, the mi_interpreter_init function would return the pointer to be used as interpreter data, which the caller (the interp_set function) would assign to interp->data. So it was indeed not possible to call mi_inferior_added, because it required interp->data to be set. - It is still not possible today to use mi_inferior_added, because it iterates over all MI UIs and to print the event on all of them. So if you do: 1. Start GDB with `-i mi` 2. Add some inferiors 3. Create a new MI UI, with `new-ui mi /dev/pts/X` When initializing the new MI UI, it will print the inferior-added events on both MI UIs. - It is necessary to use iteration, not only in case GDB creates more than one inferior up front, but also because there might be multiple inferiors when initializing a secondary MI UI, as shown above. I don't know if it is by design, that the =inferior-added events are sent to a new MI UI added with new-ui, but in any case I don't want to change the behavior with this patch. Also, when testing this, I realized it was wrong to put the gdb_flush out of the loop. It's not a simple flush as in "make sure the data is all sent to the underlying device", it's also what adds the final \n! So with the gdb_flush outside the loop, all the events were printed on the same line. I've put the terminal setting calls and the gdb_flush back into the loop, to minimize the changes. The patch would now look like this: From cb845a4f28d1761feb463914c13b0a45c97d9974 Mon Sep 17 00:00:00 2001 From: Simon Marchi Date: Wed, 15 Jan 2020 14:12:20 -0500 Subject: [PATCH] gdb: remove use of iterate_over_inferiors in mi/mi-interp.c Replace it with a range-based for. I've updated the comment in mi_interp::init, which was a bit stale. gdb/ChangeLog: * mi/mi-interp.c (report_initial_inferior): Remove. (mi_interp::init): Use range-based for to iterate over inferiors. --- gdb/mi/mi-interp.c | 49 ++++++++++++++++++++-------------------------- 1 file changed, 21 insertions(+), 28 deletions(-) diff --git a/gdb/mi/mi-interp.c b/gdb/mi/mi-interp.c index 2ac4c119961c..e77093cfa282 100644 --- a/gdb/mi/mi-interp.c +++ b/gdb/mi/mi-interp.c @@ -91,8 +91,6 @@ static void mi_memory_changed (struct inferior *inf, CORE_ADDR memaddr, ssize_t len, const bfd_byte *myaddr); static void mi_on_sync_execution_done (void); -static int report_initial_inferior (struct inferior *inf, void *closure); - /* Display the MI prompt. */ static void @@ -137,12 +135,27 @@ mi_interp::init (bool top_level) if (top_level) { - /* The initial inferior is created before this function is - called, so we need to report it explicitly. Use iteration in - case future version of GDB creates more than one inferior - up-front. */ - iterate_over_inferiors (report_initial_inferior, mi); - } + /* The initial inferior is created before this function is called, so we + need to report it explicitly when initializing the top-level MI + interpreter. + + This is also called when additional MI interpreters are added (using + the new-ui command), when multiple inferiors possibly exist, so we need + to use iteration to report all the inferiors. mi_inferior_added can't + be used, because it would print the event on all the other MI UIs. */ + + for (inferior *inf : all_inferiors ()) + { + target_terminal::scoped_restore_terminal_state term_state; + target_terminal::ours_for_output (); + + fprintf_unfiltered (mi->event_channel, + "thread-group-added,id=\"i%d\"", + inf->num); + + gdb_flush (mi->event_channel); + } + } } void @@ -1253,26 +1266,6 @@ mi_user_selected_context_changed (user_selected_what selection) } } -static int -report_initial_inferior (struct inferior *inf, void *closure) -{ - /* This function is called from mi_interpreter_init, and since - mi_inferior_added assumes that inferior is fully initialized - and top_level_interpreter_data is set, we cannot call - it here. */ - struct mi_interp *mi = (struct mi_interp *) closure; - - target_terminal::scoped_restore_terminal_state term_state; - target_terminal::ours_for_output (); - - fprintf_unfiltered (mi->event_channel, - "thread-group-added,id=\"i%d\"", - inf->num); - gdb_flush (mi->event_channel); - - return 0; -} - ui_out * mi_interp::interp_ui_out () {