From 79596cc6abd54d94270c9270ca8e8a1bb5fd1e5f Mon Sep 17 00:00:00 2001
From: Henning Stahlke <github@henningstahlke.de>
Date: Sun, 13 Jan 2019 20:55:56 +0100
Subject: [PATCH] debug.nas add Breakpoint class
---
Nasal/debug.nas | 100 ++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 89 insertions(+), 11 deletions(-)
diff --git a/Nasal/debug.nas b/Nasal/debug.nas
index 431d57afd..1fdca34ee 100644
--- a/Nasal/debug.nas
+++ b/Nasal/debug.nas
@@ -7,8 +7,12 @@
# debug.local([<frame:int>]) ... dump local variables of current
# or given frame
#
-# debug.backtrace([<comment:string>]} ... writes backtrace with local variables
-# (similar to gdb's "bt full)
+# debug.backtrace([<comment:string>], [<dump:bool=1>], [<skip_level:int=0>]}
+# ... writes backtrace (similar to gdb's "bt full)
+# dump=0: only call stack
+# dump=1 (default): with local variables
+# skip_level: remove this many levels from
+# call stack
#
# debug.proptrace([<property [, <frames>]]) ... trace property write/add/remove
# events under the <property> subtree for
@@ -264,15 +268,16 @@ var local = func(frame = 0) {
}
-var backtrace = func(desc = nil) {
- var d = desc == nil ? "" : " '" ~ desc ~ "'";
- print("\n" ~ _title("\n### backtrace" ~ d ~ " ###"));
- for (var i = 1; 1; i += 1) {
- if ((var v = caller(i)) == nil)
- return;
- print(_section(sprintf("#%-2d called from %s, line %s:", i - 1, v[2], v[3])));
- dump(v[0]);
- }
+var backtrace = func(desc = nil, dump_vars = 1, skip_level = 0) {
+ var d = (desc == nil) ? "" : " '" ~ desc ~ "'";
+ print("");
+ print(_title("### backtrace" ~ d ~ " ###"));
+ skip_level += 1;
+ for (var i = skip_level; 1; i += 1) {
+ if ((var v = caller(i)) == nil) return;
+ print(_section(sprintf("#%-2d called from %s, line %s:", i - skip_level, v[2], v[3])));
+ if (dump_vars) dump(v[0]);
+ }
}
var bt = backtrace;
@@ -433,6 +438,79 @@ var isnan = func {
return !!size(err);
}
+# Breakpoint (BP) - do conditional backtrace (BT) controlled via property tree
+# * count how often the BP was hit
+# * do only a limited number of BT, avoid flooding the log / console
+#
+# Data can be viewed / modified in the prop tree /_debug/nas/bp-<myLabel>/*
+# * tokens: number of backtraces to do; each hit will decrease this by 1
+# * hits: total number of hits
+#
+# == Example ==
+# var myBP = debug.Breakpoint.new("myLabel", 0);
+# myBP.enable(4); # allow 4 hits, then be quiet
+#
+# #at the place of interest (e.g. in some loop or class method) insert:
+# myBP.hit(); # do backtrace here if tokens > 0, reduce tokens by 1
+#
+# print(myBP.getHits()); # print total number of hits
+#
+var Breakpoint = {
+ # label: Used in property path and as text for backtrace.
+ # dump_locals: bool passed to backtrace. Dump variables in BT.
+ new: func(label, dump_locals = 1) {
+ var obj = {
+ parents: [Breakpoint],
+ _tokensN: nil,
+ tokens: 0,
+ _hitsN: nil,
+ hits: 0,
+ label: "",
+ dump_locals: num(dump_locals),
+ };
+ label = globals.string.replace(label, " ", "_");
+ obj.label = globals.string.replace(label, "/", "_");
+ var prop_path = "/_debug/nas/bp-"~obj.label~"/";
+ obj._tokensN = props.globals.getNode(prop_path~"token", 1);
+ obj._hitsN = props.globals.getNode(prop_path~"hits", 1);
+ obj._hitsN.setIntValue(0);
+ obj.disable();
+ return obj;
+ },
+
+ # enable BP and set hit limit;
+ # tokens: int > 0; default: 1 (single shot); 0 allowed (=disable);
+ enable: func(tokens = 1) {
+ if (num(tokens) == nil) tokens = 1;
+ if (tokens < 0) tokens = 0;
+ me.tokens = tokens;
+ me._tokensN.setIntValue(tokens);
+ return me;
+ },
+
+ # set tokens to zero, disables backtrace in hit()
+ disable: func {
+ me._tokensN.setIntValue(0);
+ return me;
+ },
+
+ # get total number of hits (not #backtraces done)
+ getHits: func {
+ return me.hits;
+ },
+
+ # hit the breakpoint, e.g. do backtrace if we have tokens available
+ hit: func() {
+ me.hits += 1;
+ me._hitsN.setIntValue(me.hits);
+ me.tokens = me._tokensN.getValue();
+ if (me.tokens > 0) {
+ debug.backtrace(me.label, me.dump_locals, 1);
+ me._tokensN.setValue(me.tokens - 1);
+ }
+ return me;
+ },
+};
# --prop:debug=1 enables debug mode with additional warnings
#