Add facility to track usage of functions.

Use this for plotters so we can see which ones are being used
in any given build.

Build with -DTRACK_USAGE to enable.

2 files changed, 36 insertions, 0 deletions

diff --git a/include/mupdf/fitz/system.h b/include/mupdf/fitz/system.h
index cbc10285..be5504a5 100644
--- a/include/mupdf/fitz/system.h
+++ b/include/mupdf/fitz/system.h
@@ -31,6 +31,7 @@
 #include <setjmp.h>
 
 #include "mupdf/memento.h"
+#include "mupdf/fitz/track-usage.h"
 
 #define nelem(x) (sizeof(x)/sizeof((x)[0]))
 
diff --git a/include/mupdf/fitz/track-usage.h b/include/mupdf/fitz/track-usage.h
new file mode 100644
index 00000000..6c4409fb
--- /dev/null
+++ b/include/mupdf/fitz/track-usage.h
@@ -0,0 +1,35 @@
+#ifndef TRACK_USAGE_H
+#define TRACK_USAGE_H
+
+#ifdef TRACK_USAGE
+
+typedef struct track_usage_data_s {
+	int count;
+	const char *function;
+	int line;
+	const char *desc;
+	struct track_usage_data_s *next;
+} track_usage_data_t;
+
+#define TRACK_LABEL(A) \
+	do { \
+		static track_usage_data_t USAGE_DATA = { 0 };\
+		track_usage(&USAGE_DATA, __FILE__, __LINE__, A);\
+	} while (0)
+
+#define TRACK_FN() \
+	do { \
+		static track_usage_data_t USAGE_DATA = { 0 };\
+		track_usage(&USAGE_DATA, __FILE__, __LINE__, __FUNCTION__);\
+	} while (0)
+
+void track_usage(track_usage_data_t *data, const char *function, int line, const char *desc);
+
+#else
+
+#define TRACK_LABEL(A) do { } while (0)
+#define TRACK_FN() do { } while (0)
+
+#endif
+
+#endif