From 18b1b4f7af07f6646c44fe578f86058df3833b71 Mon Sep 17 00:00:00 2001
From: david <david>
Date: Wed, 12 Dec 2001 03:49:48 +0000
Subject: [PATCH] Added --trace-read=<property> and --trace-write=<property>
 options. These will log trace messages whenever a specific property value is
 read or written through the property manager.  They do not cause FlightGear
 to poll bound values, so if a class variable that is bound is changed
 directly, no trace message will be displayed.

These options are also useful in conjunction with a debugger.
--trace-read will cause the private SimGear SGPropertyNode::trace_read
method to be invoked, and --trace-write will cause the private SimGear
SGPropertyNode::trace_write method to be invoked; in a debugger
session, a user can set breakpoints on these methods then get a
backtrace to see what specific points in the code are reading or
writing properties.
---
 src/Main/options.cxx | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/Main/options.cxx b/src/Main/options.cxx
index 44aae7246..e1002c356 100644
--- a/src/Main/options.cxx
+++ b/src/Main/options.cxx
@@ -839,9 +839,17 @@ parse_option (const string& arg)
 	fgSetString(name.c_str(), value);
 	// SG_LOG(SG_GENERAL, SG_INFO, "Setting default value of property "
 	//        << name << " to \"" << value << '"');
-    // $$$ begin - added VS Renganathan, 14 Oct 2K
-    // for multi-window outside window imagery
+    } else if ( arg.find("--trace-read=") == 0) {
+        string name = arg.substr(13);
+	SG_LOG(SG_GENERAL, SG_INFO, "Tracing reads for property " << name);
+	fgGetNode(name, true)->setAttribute(SGPropertyNode::TRACE_READ, true);
+    } else if ( arg.find("--trace-write=") == 0) {
+        string name = arg.substr(14);
+	SG_LOG(SG_GENERAL, SG_INFO, "Tracing writes for property " << name);
+	fgGetNode(name, true)->setAttribute(SGPropertyNode::TRACE_WRITE, true);
     } else if ( arg.find( "--view-offset=" ) == 0 ) {
+        // $$$ begin - added VS Renganathan, 14 Oct 2K
+        // for multi-window outside window imagery
 	string woffset = arg.substr( 14 );
 	double default_view_offset = 0.0;
 	if ( woffset == "LEFT" ) {