[pango/sysprof-tracing] Add sysprof tracing support

[Matthias Clasen <matthiasc src gnome org>]

commit 13f8625431eba74e070e846b23fcfc2a0ff2b34d
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Aug 19 16:02:10 2020 -0400

    Add sysprof tracing support
    
    Add support for adding sysprof marks.
    Strongly inspired by equivalent GLib support.

 meson.build                 | 17 +++++++++++++++
 meson_options.txt           |  4 ++++
 pango/meson.build           |  1 +
 pango/pango-trace-private.h | 53 +++++++++++++++++++++++++++++++++++++++++++++
 pango/pango-trace.c         | 40 ++++++++++++++++++++++++++++++++++
 subprojects/sysprof.wrap    |  5 +++++
 6 files changed, 120 insertions(+)
---
diff --git a/meson.build b/meson.build
index 288405cf..00b9df91 100644
--- a/meson.build
+++ b/meson.build
@@ -538,6 +538,23 @@ if cairo_dep.found()
   endif
 endif
 
+# libsysprof-capture support
+libsysprof_capture_dep = dependency('sysprof-capture-4',
+  required: get_option('sysprof'),
+  default_options: [
+    'enable_examples=false',
+    'enable_gtk=false',
+    'enable_tests=false',
+    'enable_tools=false',
+    'libsysprof=false',
+    'with_sysprofd=none',
+    'help=false',
+  ],
+  fallback: ['sysprof', 'libsysprof_capture_dep'],
+)
+pango_conf.set('HAVE_SYSPROF', libsysprof_capture_dep.found())
+pango_deps += libsysprof_capture_dep
+
 gnome = import('gnome')
 pkgconfig = import('pkgconfig')
 
diff --git a/meson_options.txt b/meson_options.txt
index 7a59fa2b..b0395b5e 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -14,3 +14,7 @@ option('use_fontconfig',
        description : 'Force using FontConfig where it is optional, on Windows and macOS.  This is ignored on 
platforms where it is required',
        type: 'boolean',
        value: 'false')
+option('sysprof',
+       type : 'feature',
+       value : 'disabled',
+       description : 'include tracing support for sysprof')
diff --git a/pango/meson.build b/pango/meson.build
index 11578ddf..4c055f52 100644
--- a/pango/meson.build
+++ b/pango/meson.build
@@ -177,6 +177,7 @@ if build_pangoft2
     'pangofc-font.c',
     'pangofc-fontmap.c',
     'pangofc-decoder.c',
+    'pango-trace.c',
   ]
 
   pangoot_headers = [
diff --git a/pango/pango-trace-private.h b/pango/pango-trace-private.h
new file mode 100644
index 00000000..5d2a4fdf
--- /dev/null
+++ b/pango/pango-trace-private.h
@@ -0,0 +1,53 @@
+/* Pango
+ * pango-trace-private.h:
+ *
+ * Copyright (C) 2020 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+
+#ifdef HAVE_SYSPROF
+#include <sysprof-capture.h>
+#endif
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+#ifdef HAVE_SYSPROF
+#define PANGO_TRACE_CURRENT_TIME SYSPROF_CAPTURE_CURRENT_TIME
+#else
+#define PANGO_TRACE_CURRENT_TIME 0
+#endif
+
+void pango_trace_mark (gint64       begin_time,
+                       const gchar *name,
+                       const gchar *message_format,
+                       ...) G_GNUC_PRINTF (3, 4);
+
+#ifndef HAVE_SYSPROF
+/* Optimise the whole call out */
+#if defined(G_HAVE_ISO_VARARGS)
+#define g_trace_mark(b, n, m, ...)
+#elif defined(G_HAVE_GNUC_VARARGS)
+#define g_trace_mark(b, n, m...)
+#else
+/* no varargs macro support; the call will have to be optimised out by the compiler */
+#endif
+#endif
+
+G_END_DECLS
diff --git a/pango/pango-trace.c b/pango/pango-trace.c
new file mode 100644
index 00000000..9f37376d
--- /dev/null
+++ b/pango/pango-trace.c
@@ -0,0 +1,40 @@
+/* Pango
+ * pango-trace.c:
+ *
+ * Copyright (C) 2020 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "pango-trace-private.h"
+
+#include <stdarg.h>
+
+void
+(pango_trace_mark) (gint64       begin_time,
+                    const gchar *name,
+                    const gchar *message_format,
+                    ...)
+{
+#ifdef HAVE_SYSPROF
+  gint64 end_time = PANGO_TRACE_CURRENT_TIME;
+  va_list args;
+
+  va_start (args, message_format);
+  sysprof_collector_mark_vprintf (begin_time, end_time - begin_time, "Pango", name, message_format, args);
+  va_end (args);
+#endif  /* HAVE_SYSPROF */
+}
diff --git a/subprojects/sysprof.wrap b/subprojects/sysprof.wrap
new file mode 100644
index 00000000..fb669463
--- /dev/null
+++ b/subprojects/sysprof.wrap
@@ -0,0 +1,5 @@
+[wrap-git]
+directory=sysprof
+url=https://gitlab.gnome.org/GNOME/sysprof.git
+revision=6b1cd7a722fcebae1ac392562c47957477ade8bf
+depth=1