From 6f36a6362982b08574e27a61d9c8716fe5aac8a8 Mon Sep 17 00:00:00 2001
From: Matthias Melcher <github@matthiasm.com>
Date: Thu, 24 Nov 2022 11:39:20 +0100
Subject: [PATCH] Fixes some FLUID bugs

Fl_Flex would not change type when it had no children.
Function evaluation could read past string end.
Fl_Window_Type would not initialise all member variables.
---
 fluid/Fl_Group_Type.cxx   | 48 ++++++++++++++++++++-------------------
 fluid/Fl_Window_Type.h    | 13 ++++++++++-
 fluid/Shortcut_Button.cxx |  5 ++--
 3 files changed, 40 insertions(+), 26 deletions(-)

diff --git a/fluid/Fl_Group_Type.cxx b/fluid/Fl_Group_Type.cxx
index d83d7fa2d..44b83e82b 100644
--- a/fluid/Fl_Group_Type.cxx
+++ b/fluid/Fl_Group_Type.cxx
@@ -315,30 +315,32 @@ void Fl_Flex_Type::remove_child(Fl_Type* a) {
 // We need to relayout existing children.
 void Fl_Flex_Type::change_subtype_to(int n) {
   Fl_Flex* f = (Fl_Flex*)o;
+  if (f->type()==n) return;
+
   int nc = f->children();
-  if (f->type()==n || nc==0) return;
-
-  int dw = Fl::box_dw(f->box());
-  int dh = Fl::box_dh(f->box());
-  int lm, tm, rm, bm;
-  f->margins(&lm, &tm, &rm, &bm);
-  int gap = f->gap();
-  int fw = f->w()-dw-lm-rm-(nc*gap);
-  if (fw<=nc) fw = nc; // avoid division by zero
-  int fh = f->h()-dh-tm-bm-(nc*gap);
-  if (fh<=nc) fh = nc; // avoid division by zero
-
-  if (f->type()==Fl_Flex::HORIZONTAL && n==Fl_Flex::VERTICAL) {
-    float scl = (float)fh/(float)fw;
-    for (int i=0; i<nc; i++) {
-      Fl_Widget* c = f->child(i);
-      c->size(f->w(), (int)(c->w()*scl));
-    }
-  } else if (f->type()==Fl_Flex::VERTICAL && n==Fl_Flex::HORIZONTAL) {
-    float scl = (float)fw/(float)fh;
-    for (int i=0; i<nc; i++) {
-      Fl_Widget* c = f->child(i);
-      c->size((int)(c->h()*scl), f->h());
+  if (nc > 0) {
+    int dw = Fl::box_dw(f->box());
+    int dh = Fl::box_dh(f->box());
+    int lm, tm, rm, bm;
+    f->margins(&lm, &tm, &rm, &bm);
+    int gap = f->gap();
+    int fw = f->w()-dw-lm-rm-(nc*gap);
+    if (fw<=nc) fw = nc; // avoid division by zero
+    int fh = f->h()-dh-tm-bm-(nc*gap);
+    if (fh<=nc) fh = nc; // avoid division by zero
+    
+    if (f->type()==Fl_Flex::HORIZONTAL && n==Fl_Flex::VERTICAL) {
+      float scl = (float)fh/(float)fw;
+      for (int i=0; i<nc; i++) {
+        Fl_Widget* c = f->child(i);
+        c->size(f->w(), (int)(c->w()*scl));
+      }
+    } else if (f->type()==Fl_Flex::VERTICAL && n==Fl_Flex::HORIZONTAL) {
+      float scl = (float)fw/(float)fh;
+      for (int i=0; i<nc; i++) {
+        Fl_Widget* c = f->child(i);
+        c->size((int)(c->h()*scl), f->h());
+      }
     }
   }
   f->type(n);
diff --git a/fluid/Fl_Window_Type.h b/fluid/Fl_Window_Type.h
index 41cf73f4b..05a2777ca 100644
--- a/fluid/Fl_Window_Type.h
+++ b/fluid/Fl_Window_Type.h
@@ -67,7 +67,18 @@ protected:
 
 public:
 
-  Fl_Window_Type() { drag = dx = dy = 0; sr_min_w = sr_min_h = sr_max_w = sr_max_h = 0; }
+  Fl_Window_Type() :
+    mx(0), my(0),
+    x1(0), y1(0),
+    bx(0), by(0), br(0), bt(0),
+    sx(0), sy(0), sr(0), st(0),
+    dx(0), dy(0),
+    drag(0),
+    numselected(0),
+    recalc(0),
+    modal(0), non_modal(0),
+    sr_min_w(0), sr_min_h(0), sr_max_w(0), sr_max_h(0)
+  { }
   uchar modal, non_modal;
 
   Fl_Type *make(Strategy strategy);
diff --git a/fluid/Shortcut_Button.cxx b/fluid/Shortcut_Button.cxx
index 517eee624..9c64b760a 100644
--- a/fluid/Shortcut_Button.cxx
+++ b/fluid/Shortcut_Button.cxx
@@ -283,14 +283,15 @@ int Fluid_Coord_Input::eval(uchar *&s, int prio) const {
     } else {
       return v; // syntax error
     }
-    c = *s++;
+    c = *s;
+    if (c) s++;
   }
   return v;
 }
 
 /**
  Evaluate a formula into an integer.
- The interpreter understand unary plus and minus, basic integer math
+ The interpreter understands unary plus and minus, basic integer math
  (+, -, *, /), brackets, and can handle a user defined list of variables
  by name. There is no error checking. We assume that the formula is
  entered correctly.