[gnome-builder] plugins/sysprof: setup control channel for gnome-builder-sysprof

[Christian Hergert <chergert src gnome org>]

commit ceca681f1007a5449764c7a877484a3c311714e4
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jul 21 12:14:53 2022 -0700

    plugins/sysprof: setup control channel for gnome-builder-sysprof
    
    The goal here is for Builder to control this intermediate process and be
    able to deliver signals/force-exit through the intermediate to the target
    subprocess. Additionally, it can get some information about what is
    going on which we could proxy to IdeNotification at some point.
    
    We still need the Builder-side of this in GbpSysprofTool.

 src/plugins/sysprof/gnome-builder-sysprof.c       | 249 +++++++++++++++++++++-
 src/plugins/sysprof/meson.build                   |  17 +-
 src/plugins/sysprof/org.gnome.Builder.Sysprof.xml |  36 ++++
 3 files changed, 294 insertions(+), 8 deletions(-)
---
diff --git a/src/plugins/sysprof/gnome-builder-sysprof.c b/src/plugins/sysprof/gnome-builder-sysprof.c
index a2f12e2aa..3c771aab3 100644
--- a/src/plugins/sysprof/gnome-builder-sysprof.c
+++ b/src/plugins/sysprof/gnome-builder-sysprof.c
@@ -22,9 +22,15 @@
 
 #include <errno.h>
 #include <stdlib.h>
-#include <sysprof.h>
 #include <unistd.h>
 
+#include <glib-unix.h>
+#include <gio/gunixinputstream.h>
+#include <gio/gunixoutputstream.h>
+
+#include <ipc-sysprof.h>
+#include <sysprof.h>
+
 #define BUFFER_SIZE (4096L*16L) /* 64KB */
 
 static gboolean forward_fd_func (const char  *option_name,
@@ -33,6 +39,10 @@ static gboolean forward_fd_func (const char  *option_name,
                                  GError     **error);
 
 static GMainLoop *main_loop;
+static GSubprocess *subprocess;
+static char *subprocess_ident;
+static gboolean subprocess_finished;
+static IpcSysprof *service;
 static int exit_code = EXIT_SUCCESS;
 static int read_fd = -1;
 static int write_fd = -1;
@@ -78,6 +88,24 @@ static const GOptionEntry options[] = {
   { NULL }
 };
 
+G_GNUC_PRINTF (1, 2)
+static void
+message (const char *format,
+         ...)
+{
+  g_autofree char *formatted = NULL;
+  va_list args;
+
+  if (service == NULL)
+    return;
+
+  va_start (args, format);
+  formatted = g_strdup_vprintf (format, args);
+  va_end (args);
+
+  ipc_sysprof_emit_log (service, formatted);
+}
+
 #define GBP_TYPE_SPAWN_SOURCE (gbp_spawn_source_get_type())
 G_DECLARE_FINAL_TYPE (GbpSpawnSource, gbp_spawn_source, GBP, SPAWN_SOURCE, GObject)
 
@@ -143,6 +171,59 @@ gbp_spawn_source_init (GbpSpawnSource *self)
 {
 }
 
+#define IPC_TYPE_SYSPROF_IMPL (ipc_sysprof_impl_get_type())
+G_DECLARE_FINAL_TYPE (IpcSysprofImpl, ipc_sysprof_impl, IPC, SYPSROF_IMPL, IpcSysprofSkeleton)
+
+struct _IpcSysprofImpl
+{
+  IpcSysprofSkeleton parent_instance;
+};
+
+static gboolean
+handle_force_exit (IpcSysprof            *sysprof,
+                   GDBusMethodInvocation *invocation)
+{
+  if (subprocess && !subprocess_finished)
+    g_subprocess_force_exit (subprocess);
+
+  ipc_sysprof_complete_force_exit (sysprof, invocation);
+
+  return TRUE;
+}
+
+static gboolean
+handle_send_signal (IpcSysprof            *sysprof,
+                    GDBusMethodInvocation *invocation,
+                    int                    signum)
+{
+  if (subprocess && !subprocess_finished)
+    g_subprocess_send_signal (subprocess, signum);
+
+  ipc_sysprof_complete_send_signal (sysprof, invocation);
+
+  return TRUE;
+}
+
+static void
+service_iface_init (IpcSysprofIface *iface)
+{
+  iface->handle_force_exit = handle_force_exit;
+  iface->handle_send_signal = handle_send_signal;
+}
+
+G_DEFINE_FINAL_TYPE_WITH_CODE (IpcSysprofImpl, ipc_sysprof_impl, IPC_TYPE_SYSPROF_SKELETON,
+                               G_IMPLEMENT_INTERFACE (IPC_TYPE_SYSPROF, service_iface_init))
+
+static void
+ipc_sysprof_impl_class_init (IpcSysprofImplClass *klass)
+{
+}
+
+static void
+ipc_sysprof_impl_init (IpcSysprofImpl *self)
+{
+}
+
 static gboolean
 forward_fd_func (const char  *option_name,
                  const char  *option_value,
@@ -219,6 +300,9 @@ static void
 profiler_failed_cb (SysprofProfiler *profiler,
                     const GError    *error)
 {
+  g_assert (SYSPROF_IS_LOCAL_PROFILER (profiler));
+  g_assert (error != NULL);
+
   g_printerr ("Profiling failed: %s", error->message);
   exit_code = EXIT_FAILURE;
   g_main_loop_quit (main_loop);
@@ -227,9 +311,37 @@ profiler_failed_cb (SysprofProfiler *profiler,
 static void
 profiler_stopped_cb (SysprofProfiler *profiler)
 {
+  g_assert (SYSPROF_IS_LOCAL_PROFILER (profiler));
+
   g_main_loop_quit (main_loop);
 }
 
+static void
+subprocess_spawned_cb (SysprofLocalProfiler *profiler,
+                       GSubprocess          *new_subprocess)
+{
+  g_assert (SYSPROF_IS_LOCAL_PROFILER (profiler));
+  g_assert (G_IS_SUBPROCESS (new_subprocess));
+
+  g_set_object (&subprocess, new_subprocess);
+
+  subprocess_ident = g_strdup (g_subprocess_get_identifier (subprocess));
+
+  message ("Created process %s", subprocess_ident);
+}
+
+static void
+subprocess_finished_cb (SysprofLocalProfiler *profiler,
+                        GSubprocess          *new_subprocess)
+{
+  g_assert (SYSPROF_IS_LOCAL_PROFILER (profiler));
+  g_assert (G_IS_SUBPROCESS (new_subprocess));
+
+  subprocess_finished = TRUE;
+
+  message ("Process %s exited", subprocess_ident);
+}
+
 static void
 split_argv (int     argc,
             char  **argv,
@@ -279,15 +391,37 @@ warn_error (GError **error)
     }
 }
 
+static GDBusConnection *
+create_connection (GIOStream  *stream,
+                   GError    **error)
+{
+  GDBusConnection *ret;
+
+  g_assert (G_IS_IO_STREAM (stream));
+  g_assert (main_loop != NULL);
+  g_assert (error != NULL);
+
+  if ((ret = g_dbus_connection_new_sync (stream, NULL,
+                                          G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING,
+                                          NULL, NULL, error)))
+    {
+      g_dbus_connection_set_exit_on_close (ret, FALSE);
+      g_signal_connect_swapped (ret, "closed", G_CALLBACK (g_main_loop_quit), main_loop);
+    }
+
+  return ret;
+}
+
 int
 main (int   argc,
       char *argv[])
 {
   g_autoptr(SysprofCaptureWriter) writer = NULL;
   g_autoptr(SysprofProfiler) profiler = NULL;
-  g_autoptr(GOptionContext) context = NULL;
+  g_autoptr(GDBusConnection) connection = NULL;
   g_autoptr(GDBusConnection) session_bus = NULL;
   g_autoptr(GDBusConnection) system_bus = NULL;
+  g_autoptr(GOptionContext) context = NULL;
   g_autoptr(GError) error = NULL;
   g_auto(GStrv) our_argv = NULL;
   g_auto(GStrv) sub_argv = NULL;
@@ -297,26 +431,36 @@ main (int   argc,
 
   sysprof_clock_init ();
 
-  split_argv (argc, argv, &our_argc, &our_argv, &sub_argc, &sub_argv);
+  g_set_prgname ("gnome-builder-sysprof");
+  g_set_application_name ("gnome-builder-sysprof");
+
+  /* Ignore SIGPIPE as we're using pipes to IPC */
+  signal (SIGPIPE, SIG_IGN);
 
+  /* Split argv into pre/post -- command split */
+  split_argv (argc, argv, &our_argc, &our_argv, &sub_argc, &sub_argv);
   g_assert (our_argc >= 0);
   g_assert (sub_argc >= 0);
 
+  /* Parse command line options pre -- */
   context = g_option_context_new ("-- COMMAND");
   g_option_context_add_main_entries (context, options, NULL);
-
   if (!g_option_context_parse (context, &our_argc, &our_argv, &error))
     {
       g_printerr ("%s\n", error->message);
       return EXIT_FAILURE;
     }
 
+  /* Make sure we have a filename to capture to */
   if (capture_filename == NULL)
     {
       g_printerr ("You must provide --capture=PATH\n");
       return EXIT_FAILURE;
     }
 
+  /* Setup main loop, we'll need it going forward for things
+   * like async D-Bus, waiting for child processes, etc.
+   */
   main_loop = g_main_loop_new (NULL, FALSE);
 
   /* First spin up our bus connections */
@@ -325,6 +469,55 @@ main (int   argc,
   if (!(system_bus = g_bus_get_sync (G_BUS_TYPE_SYSTEM, NULL, NULL)))
     warn_error (&error);
 
+  /* Now setup our private p2p D-Bus connection to the controller */
+  if (read_fd != -1 || write_fd != -1)
+    {
+      g_autoptr(GIOStream) stream = NULL;
+      g_autoptr(GInputStream) in_stream = NULL;
+      g_autoptr(GOutputStream) out_stream = NULL;
+
+      /* Both must be set, not just one side */
+      if (read_fd == -1 || write_fd == -1)
+        {
+          g_printerr ("You must specify both --read-fd and --write-fd\n");
+          return EXIT_FAILURE;
+        }
+
+      /* We need these FDs non-blocking for async IO */
+      if (!g_unix_set_fd_nonblocking (read_fd, TRUE, &error) ||
+          !g_unix_set_fd_nonblocking (write_fd, TRUE, &error))
+        {
+          g_printerr ("Failed to set FDs in nonblocking mode: %s\n",
+                      error->message);
+          return EXIT_FAILURE;
+        }
+
+      /* Create stream using FDs provided to us */
+      in_stream = g_unix_input_stream_new (read_fd, FALSE);
+      out_stream = g_unix_output_stream_new (write_fd, FALSE);
+      stream = g_simple_io_stream_new (in_stream, out_stream);
+
+      /* Create connection using our private stream from the controller */
+      if (!(connection = create_connection (stream, &error)))
+        {
+          g_printerr ("Failed to setup P2P D-Bus connection: %s\n",
+                      error->message);
+          return EXIT_FAILURE;
+        }
+
+      /* Now export our service at "/" (but don't start processing messages
+       * until we start the profiler, further on.
+       */
+      service = g_object_new (IPC_TYPE_SYSPROF_IMPL, NULL);
+      if (!g_dbus_interface_skeleton_export (G_DBUS_INTERFACE_SKELETON (service),
+                                             connection, "/", &error))
+        {
+          g_printerr ("Failed to export service over D-Bus connection: %s",
+                      error->message);
+          return EXIT_FAILURE;
+        }
+    }
+
   /* Now start setting up our profiler */
   profiler = sysprof_local_profiler_new ();
 
@@ -335,6 +528,10 @@ main (int   argc,
    */
   sysprof_profiler_set_whole_system (profiler, TRUE);
 
+  /* If -- was ommitted or there are no commands, just profile the entire
+   * system without spawning anything. Really only useful when testing the
+   * agent without Builder.
+   */
   if (sub_argc >= 0)
     {
       sysprof_profiler_set_spawn (profiler, TRUE);
@@ -387,7 +584,9 @@ main (int   argc,
               "disable-governor", TRUE,
               NULL);
 
-  /* Bail when we've failed or finished */
+  /* Bail when we've failed or finished and track the subprocess
+   * so that we can deliver signals to it.
+   */
   g_signal_connect (profiler,
                     "failed",
                     G_CALLBACK (profiler_failed_cb),
@@ -396,13 +595,30 @@ main (int   argc,
                     "stopped",
                     G_CALLBACK (profiler_stopped_cb),
                     NULL);
+  g_signal_connect (profiler,
+                    "subprocess-spawned",
+                    G_CALLBACK (subprocess_spawned_cb),
+                    NULL);
+  g_signal_connect (profiler,
+                    "subprocess-finished",
+                    G_CALLBACK (subprocess_finished_cb),
+                    NULL);
 
   /* Start the profiler */
   sysprof_profiler_start (profiler);
 
+  /* Now tell the connection to start processing messages that are
+   * delivered from the controller, or signals destined back.
+   */
+  if (connection != NULL)
+    g_dbus_connection_start_message_processing (connection);
+
   /* Wait for profiler to finish */
   g_main_loop_run (main_loop);
 
+  /* Notify that some more work needs to proceed */
+  message ("Extracting callgraph symbols");
+
   /* Let anything in-flight finish */
   main_context = g_main_loop_get_context (main_loop);
   while (g_main_context_pending (main_context))
@@ -411,5 +627,28 @@ main (int   argc,
   /* Now make sure our bits are on disk */
   sysprof_capture_writer_flush (writer);
 
+  /* Try to exit the same way as the subprocess did to propagate that
+   * back into Builder who is watching *this* process.
+   */
+  if (subprocess_finished)
+    {
+      g_assert (G_IS_SUBPROCESS (subprocess));
+      g_assert (g_subprocess_get_if_exited (subprocess) ||
+                g_subprocess_get_if_signaled (subprocess));
+
+      if (g_subprocess_get_if_signaled (subprocess))
+        {
+          int signum = g_subprocess_get_term_sig (subprocess);
+          /* Try to exit in the same manner, or SIGKILL if that doesn't
+           * work, or just EXIT_FAILURE as last resort.
+           */
+          raise (signum);
+          raise (SIGKILL);
+          return EXIT_FAILURE;
+        }
+
+      exit_code = g_subprocess_get_exit_status (subprocess);
+    }
+
   return exit_code;
 }
diff --git a/src/plugins/sysprof/meson.build b/src/plugins/sysprof/meson.build
index 6b1b50b4a..73e00092c 100644
--- a/src/plugins/sysprof/meson.build
+++ b/src/plugins/sysprof/meson.build
@@ -1,13 +1,24 @@
 if get_option('plugin_sysprof')
 
-libsysprof_dep = dependency('sysprof-4', version: '>= 3.45.0')
-libsysprof_ui_dep = dependency('sysprof-ui-5', version: '>= 3.45.0')
+sysprof_req_version = '3.45.1'
+sysprof_req = '>= @0@'.format(sysprof_req_version)
+
+libsysprof_dep = dependency('sysprof-4', version: sysprof_req)
+libsysprof_ui_dep = dependency('sysprof-ui-5', version: sysprof_req)
 
 plugins_deps += [
   libsysprof_dep,
   libsysprof_ui_dep,
 ]
 
+ipc_sysprof_src = gnome.gdbus_codegen('ipc-sysprof',
+           sources: 'org.gnome.Builder.Sysprof.xml',
+  interface_prefix: 'org.gnome.Builder.',
+         namespace: 'Ipc',
+        extra_args: ['--glib-min-required=@0@'.format(glib_req_version)],
+)
+plugins_sources += ipc_sysprof_src
+
 plugins_sources += files([
   'sysprof-plugin.c',
   'gbp-sysprof-page.c',
@@ -26,7 +37,7 @@ plugins_sources += plugin_sysprof_resources
 
 install_data(['org.gnome.builder.sysprof.gschema.xml'], install_dir: schema_dir)
 
-gnome_builder_sysprof_sources = ['gnome-builder-sysprof.c']
+gnome_builder_sysprof_sources = ['gnome-builder-sysprof.c', ipc_sysprof_src]
 gnome_builder_sysprof_deps = [libsysprof_dep]
 gnome_builder_sysprof = executable('gnome-builder-sysprof', gnome_builder_sysprof_sources,
            install: true,
diff --git a/src/plugins/sysprof/org.gnome.Builder.Sysprof.xml 
b/src/plugins/sysprof/org.gnome.Builder.Sysprof.xml
new file mode 100644
index 000000000..b2c2d1ffb
--- /dev/null
+++ b/src/plugins/sysprof/org.gnome.Builder.Sysprof.xml
@@ -0,0 +1,36 @@
+<!DOCTYPE node PUBLIC
+        "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
+        "http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd"; >
+<node xmlns:doc="http://www.freedesktop.org/dbus/1.0/doc.dtd";>
+  <!--
+    Copyright 2022 Christian Hergert <chergert redhat com>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+    SPDX-License-Identifier: GPL-3.0-or-later
+  -->
+  <interface name="org.gnome.Builder.Sysprof">
+    <method name="ForceExit"/>
+    <method name="SendSignal">
+      <arg name="signum" direction="in" type="i">
+        <doc:doc><doc:summary>The signal number to deliver.</doc:summary></doc:doc>
+      </arg>
+    </method>
+    <signal name="Log">
+      <arg name="message" direction="in" type="s">
+        <doc:doc><doc:summary>The log message to be displayed.</doc:summary></doc:doc>
+      </arg>
+    </signal>
+  </interface>
+</node>