profiler: add SPSProfiler implementation

Currently this is Linux only as it requires the Linux implementation of
POSIX signals.

There is a simple API, and the profile output is written to
/tmp/gjs-profile-<pid>. Description of the capture format is provided
in profile.cpp.

For apps started with gjs-console, you can toggle on/off profiling by
sending SIGUSR2 to the process.

Makefile.am

@@ -37,6 +37,7 @@ nobase_gjs_module_include_HEADERS =	\
 	gjs/byteArray.h		\
 	gjs/importer.h		\
 	gjs/jsapi-util.h	\
+	gjs/profiler.h		\
 	gjs/runtime.h		\
 	gjs/type-module.h	\
 	gjs/mem.h		\
@@ -59,16 +60,19 @@ nobase_gjs_module_include_HEADERS =	\
 	gi/gtype.h	\
 	gi/gerror.h
 
-noinst_HEADERS +=		\
-	gjs/jsapi-private.h	\
-	gjs/context-private.h	\
-	gi/proxyutils.h		\
-	util/crash.h		\
-	util/hash-x32.h		\
-	util/error.h		\
-	util/glib.h		\
-	util/log.h		\
-	util/misc.h
+noinst_HEADERS +=			\
+	gjs/jsapi-private.h		\
+	gjs/context-private.h		\
+	gi/proxyutils.h			\
+	util/crash.h			\
+	util/hash-x32.h			\
+	util/error.h			\
+	util/glib.h			\
+	util/log.h			\
+	util/misc.h			\
+	util/sp-capture-reader.h	\
+	util/sp-capture-types.h		\
+	util/sp-capture-writer.h
 
 ########################################################################
 pkgconfigdir = $(libdir)/pkgconfig
@@ -93,6 +97,7 @@ libgjs_la_CPPFLAGS =		\
 	$(GJS_CFLAGS)	\
 	$(gjs_directory_defines)\
 	-I$(top_srcdir)/gi	\
+	-I$(top_srcdir)/util	\
 	-DGJS_COMPILATION
 libgjs_la_LDFLAGS = 		\
 	$(EXTRA_LINK_FLAGS)	\
@@ -123,6 +128,7 @@ libgjs_la_SOURCES =		\
 	gjs/jsapi-util-string.cpp	\
 	gjs/mem.cpp		\
 	gjs/native.cpp		\
+	gjs/profiler.cpp	\
 	gjs/runtime.cpp		\
 	gjs/stack.cpp		\
 	gjs/type-module.cpp	\
@@ -133,7 +139,9 @@ libgjs_la_SOURCES =		\
 	util/glib.cpp		\
 	util/crash.cpp		\
 	util/log.cpp		\
-	util/misc.cpp
+	util/misc.cpp		\
+	util/sp-capture-reader.c	\
+	util/sp-capture-writer.c
 
 # For historical reasons, some files live in gi/
 libgjs_la_SOURCES += \

gjs/compat.h

@@ -31,7 +31,9 @@
 
 #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
 _Pragma("GCC diagnostic push")
+#ifndef __cplusplus
 _Pragma("GCC diagnostic ignored \"-Wstrict-prototypes\"")
+#endif
 _Pragma("GCC diagnostic ignored \"-Winvalid-offsetof\"")
 #endif
 #include <jsapi.h>

gjs/console.cpp

@@ -28,10 +28,12 @@
 
 #include <gjs/gjs.h>
 #include <gjs/coverage.h>
+#include <gjs/profiler.h>
 
 static char **include_path = NULL;
 static char **coverage_prefixes = NULL;
 static char *coverage_output_path = NULL;
+static char *profile_output_path = NULL;
 static char *command = NULL;
 
 static const char *GJS_COVERAGE_CACHE_FILE_NAME = ".internal-gjs-coverage-cache";
@@ -41,6 +43,7 @@ static GOptionEntry entries[] = {
     { "coverage-prefix", 'C', 0, G_OPTION_ARG_STRING_ARRAY, &coverage_prefixes, "Add the prefix PREFIX to the list of files to generate coverage info for", "PREFIX" },
     { "coverage-output", 0, 0, G_OPTION_ARG_STRING, &coverage_output_path, "Write coverage output to a directory DIR. This option is mandatory when using --coverage-path", "DIR", },
     { "include-path", 'I', 0, G_OPTION_ARG_STRING_ARRAY, &include_path, "Add the directory DIR to the list of directories to search for js files.", "DIR" },
+    { "profile-output", 0, 0, G_OPTION_ARG_FILENAME, &profile_output_path, "Enable the profiler and Write output to FILE", "FILE" },
     { NULL }
 };
 
@@ -65,6 +68,7 @@ main(int argc, char **argv)
     GError *error = NULL;
     GjsContext *js_context;
     GjsCoverage *coverage = NULL;
+    GjsProfiler *profiler;
     char *script;
     const char *filename;
     const char *program_name;
@@ -132,6 +136,16 @@ main(int argc, char **argv)
         g_free(path_to_cache_file);
     }
 
+    profiler = gjs_profiler_new(js_context);
+
+    /* Allow SIGUSR2 (with sigaction param) to enable/disable */
+    gjs_profiler_setup_signals();
+
+    if (profile_output_path) {
+        gjs_profiler_set_filename(profiler, profile_output_path);
+        gjs_profiler_start(profiler);
+    }
+
     /* prepare command line arguments */
     if (!gjs_context_define_string_array(js_context, "ARGV",
                                          argc - 1, (const char**)argv + 1,
@@ -158,6 +172,7 @@ main(int argc, char **argv)
         gjs_coverage_write_statistics(coverage,
                                       coverage_output_path);
  
+    gjs_profiler_free(profiler);
     g_object_unref(js_context);
     g_free(script);
     exit(code);

gjs/gjs-module.h

@@ -28,6 +28,7 @@
 #include <gjs/native.h>
 #include <gjs/mem.h>
 #include <gjs/importer.h>
+#include <gjs/profiler.h>
 #include <gjs/runtime.h>
 #include <gjs/jsapi-util.h>
 

gjs/jsapi-private.cpp

@@ -33,7 +33,9 @@
 
 #include <string.h>
 #pragma GCC diagnostic push
+#ifndef __cplusplus
 #pragma GCC diagnostic ignored "-Wstrict-prototypes"
+#endif
 #pragma GCC diagnostic ignored "-Winvalid-offsetof"
 #include <jsfriendapi.h>
 #pragma GCC diagnostic pop