[samples] Clean up the profiler sample and add a simple makefile.

3 files changed, 60 insertions, 25 deletions

diff --git a/samples/profiler/.gitignore b/samples/profiler/.gitignore
new file mode 100644
index 00000000000..cc36d59f1fe
--- /dev/null
+++ b/samples/profiler/.gitignore
@@ -0,0 +1,2 @@
+/libmono-profiler-sample.so
+/libmono-profiler-sample.dylib
diff --git a/samples/profiler/Makefile b/samples/profiler/Makefile
new file mode 100644
index 00000000000..365d861cabd
--- /dev/null
+++ b/samples/profiler/Makefile
@@ -0,0 +1,13 @@
+.PHONY: all linux osx clean
+
+all:
+
+linux:
+	gcc -fPIC -shared -o libmono-profiler-sample.so sample.c `pkg-config --cflags mono-2`
+
+osx:
+	clang -undefined suppress -flat_namespace -o mono-profiler-sample.dylib sample.c `pkg-config --cflags mono-2`
+
+clean:
+	$(RM) -f libmono-profiler-sample.so
+	$(RM) -f libmono-profiler-sample.dylib
diff --git a/samples/profiler/sample.c b/samples/profiler/sample.c
index a210317e913..35e578be155 100644
--- a/samples/profiler/sample.c
+++ b/samples/profiler/sample.c
@@ -1,56 +1,76 @@
-#include <mono/metadata/profiler.h>
-
 /*
- * Bare bones profiler. Compile with:
+ * Bare bones profiler showing how a profiler module should be structured.
+ *
+ * Compilation:
+ * - Linux: gcc -fPIC -shared -o libmono-profiler-sample.so sample.c `pkg-config --cflags mono-2`
+ * - OS X: clang -undefined suppress -flat_namespace -o mono-profiler-sample.dylib sample.c `pkg-config --cflags mono-2`
  *
- * linux : gcc -fPIC -shared -o libmono-profiler-sample.so sample.c `pkg-config --cflags --libs mono-2`
- * mac : gcc -o mono-profiler-sample.dylib sample.c -lz `pkg-config --cflags mono-2` -undefined suppress -flat_namespace
- * linux with a custom prefix (e.g. --prefix=/opt/my-mono-build):
- *	gcc -fPIC -shared -o libmono-profiler-sample.so sample.c `PKG_CONFIG_PATH=/opt/my-mono-build/lib/pkgconfig/ pkg-config --cflags --libs mono-2`
+ * If you're using a custom prefix for your Mono installation (e.g. /opt/mono),
+ * pkg-config must be invoked like this: PKG_CONFIG_PATH=/opt/mono pkg-config --cflags mono-2
  *
- * Install the binary where the dynamic loader can find it. eg /usr/lib etc.
- * For a custom prefix build, <prefix>/lib would also work.
- * Then run mono with:
- * mono --profile=sample your_application.exe
+ * Install the resulting shared library where the dynamic loader can find it,
+ * e.g. /usr/local/lib or /opt/mono (custom prefix).
  *
- * Note if you name a profiler with more than 8 characters (eg sample6789) appears to not work
+ * To use the module: mono --profile=sample hello.exe
  */
 
+#include <mono/metadata/profiler.h>
+
+/*
+ * Defining a type called _MonoProfiler will complete the opaque MonoProfiler
+ * type, which is used throughout the profiler API.
+ */
 struct _MonoProfiler {
+	/* Handle obtained from mono_profiler_create (). */
+	MonoProfilerHandle handle;
+
+	/* Counts the number of calls observed. */
 	unsigned long long ncalls;
 };
 
-static MonoProfiler prof_instance;
+/*
+ * Use static storage for the profiler structure for simplicity. The structure
+ * can be allocated dynamically as well, if needed.
+ */
+static MonoProfiler profiler;
 
-/* called at the end of the program */
+/*
+ * Callback invoked after the runtime finishes shutting down. Managed code can
+ * no longer run and most runtime services are unavailable.
+ */
 static void
-sample_shutdown (MonoProfiler *prof)
+sample_shutdown_end (MonoProfiler *prof)
 {
-	printf("total number of calls: %llu\n", prof->ncalls);
+	printf ("Total number of calls: %llu\n", prof->ncalls);
 }
 
+/*
+ * Method enter callback invoked on entry to all instrumented methods.
+ */
 static void
 sample_method_enter (MonoProfiler *prof, MonoMethod *method, MonoProfilerCallContext *ctx)
 {
 	prof->ncalls++;
 }
 
+/*
+ * Filter callback that decides which methods to instrument and how.
+ */
 static MonoProfilerCallInstrumentationFlags
-sample_instrumentation_filter (MonoProfiler *prof, MonoMethod *method)
+sample_call_instrumentation_filter (MonoProfiler *prof, MonoMethod *method)
 {
 	return MONO_PROFILER_CALL_INSTRUMENTATION_ENTER;
 }
 
-/* the entry point */
+/*
+ * The entry point function invoked by the Mono runtime.
+ */
 void
 mono_profiler_init_sample (const char *desc)
 {
-	MonoProfiler *prof = &prof_instance;
+	profiler.handle = mono_profiler_create (&profiler);
 
-	MonoProfilerHandle handle = mono_profiler_create (prof);
-	mono_profiler_set_runtime_shutdown_end_callback (handle, sample_shutdown);
-	mono_profiler_set_call_instrumentation_filter_callback (handle, sample_instrumentation_filter);
-	mono_profiler_set_method_enter_callback (handle, sample_method_enter);
+	mono_profiler_set_runtime_shutdown_end_callback (profiler.handle, sample_shutdown_end);
+	mono_profiler_set_call_instrumentation_filter_callback (profiler.handle, sample_call_instrumentation_filter);
+	mono_profiler_set_method_enter_callback (profiler.handle, sample_method_enter);
 }
-
-