From 0fb2a55fc8794f29053434c1ce2a94c7746b2b58 Mon Sep 17 00:00:00 2001
From: Greg Ercolano <erco@seriss.com>
Date: Thu, 23 Nov 2017 19:34:33 +0000
Subject: [PATCH] Fixes issued raised in STR #3422; Fl_Text_Display constructor
 order issues; organize member initialization first, method calls last.

Also:
    Reorg'ed member initialization to match order in .H
    to detect missing member inits.

    Noticed member mModifyingTabDistance is unused.
    Tagged with XXX: but left in place, since it's
    a protected member, and might be utilized by user code.
    We should probably remove this member.



git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12570 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
---
 FL/Fl_Text_Display.H    |   5 +-
 src/Fl_Text_Display.cxx | 126 +++++++++++++++++++++-------------------
 2 files changed, 69 insertions(+), 62 deletions(-)

diff --git a/FL/Fl_Text_Display.H b/FL/Fl_Text_Display.H
index 22853bb46..fe84076a6 100644
--- a/FL/Fl_Text_Display.H
+++ b/FL/Fl_Text_Display.H
@@ -558,9 +558,8 @@ protected:
   int mNLinesDeleted;           /* Number of lines deleted during
                                  buffer modification (only used
                                  when resynchronization is suppressed) */
-  int mModifyingTabDistance;    /* Whether tab distance is being
-                                 modified */
-  
+  int mModifyingTabDistance;    /* Whether tab distance is being modified XXX: UNUSED */
+
   mutable double mColumnScale; /* Width in pixels of an average character. This
                                  value is calculated as needed (lazy eval); it 
                                  needs to be mutable so that it can be calculated
diff --git a/src/Fl_Text_Display.cxx b/src/Fl_Text_Display.cxx
index 36b381721..b70327898 100644
--- a/src/Fl_Text_Display.cxx
+++ b/src/Fl_Text_Display.cxx
@@ -97,82 +97,90 @@ static int scroll_x = 0;
  */
 Fl_Text_Display::Fl_Text_Display(int X, int Y, int W, int H, const char* l)
 : Fl_Group(X, Y, W, H, l) {
-  int i;
 
-  mMaxsize = 0;
+  // Member initialization: same order as declared in .H file
+  //    Any Fl_Text_Display methods should only be called /after/ all
+  //    members initialized; avoids methods referencing uninitialized values.
+  //
   damage_range1_start = damage_range1_end = -1;
   damage_range2_start = damage_range2_end = -1;
-  dragPos = dragging = 0;
-  dragType = DRAG_CHAR;
-  display_insert_position_hint = 0;
-  shortcut_ = 0;
+  mCursorPos = 0;
+  mCursorOn = 0;
+  mCursorOldY = -100;
+  mCursorToHint = NO_HINT;
+  mCursorStyle = NORMAL_CURSOR;
+  mCursorPreferredXPos = -1;
+  mNVisibleLines = 1;
+  mNBufferLines = 0;
+  mBuffer = NULL;
+  mStyleBuffer = NULL;
+  mFirstChar = 0;
+  mLastChar = 0;
+  mContinuousWrap = 0;
+  mWrapMarginPix = 0;
+  mLineStarts = new int[mNVisibleLines];
+  { // This code unused unless mNVisibleLines is ever initialized >1
+    for (int i=1; i<mNVisibleLines; i++) mLineStarts[i] = -1;
+  }
+  mLineStarts[0] = 0;
+  mTopLineNum = 1;
+  mAbsTopLineNum = 1;
+  mNeedAbsTopLineNum = 0;
+  mHorizOffset = 0;
+  mTopLineNumHint = 1;
+  mHorizOffsetHint = 0;
+  mNStyles = 0;
+  mStyleTable = NULL;
+  mUnfinishedStyle = 0;
+  mUnfinishedHighlightCB = 0;
+  mHighlightCBArg = 0;
+  mMaxsize = 0;
+  mSuppressResync = 0;
+  mNLinesDeleted = 0;
+  mModifyingTabDistance = 0;	// XXX: UNUSED
+  mColumnScale = 0;
+  mCursor_color = FL_FOREGROUND_COLOR;
 
-  color(FL_BACKGROUND2_COLOR, FL_SELECTION_COLOR);
-  box(FL_DOWN_FRAME);
-  textsize(FL_NORMAL_SIZE);
-  textcolor(FL_FOREGROUND_COLOR);
-  textfont(FL_HELVETICA);
-  set_flag(SHORTCUT_LABEL);
+  mHScrollBar = new Fl_Scrollbar(0,0,1,1);
+  mHScrollBar->callback((Fl_Callback*)h_scrollbar_cb, this);
+  mHScrollBar->type(FL_HORIZONTAL);
+
+  mVScrollBar = new Fl_Scrollbar(0,0,1,1);
+  mVScrollBar->callback((Fl_Callback*)v_scrollbar_cb, this);
+
+  scrollbar_width_ = 0;		// 0: default from Fl::scrollbar_size()
+  scrollbar_align_ = FL_ALIGN_BOTTOM_RIGHT;
+
+  dragPos = 0;
+  dragType = DRAG_CHAR;
+  dragging = 0;
+  display_insert_position_hint = 0;
 
   text_area.x = 0;
   text_area.y = 0;
   text_area.w = 0;
   text_area.h = 0;
 
-  mVScrollBar = new Fl_Scrollbar(0,0,1,1);
-  mVScrollBar->callback((Fl_Callback*)v_scrollbar_cb, this);
-  mHScrollBar = new Fl_Scrollbar(0,0,1,1);
-  mHScrollBar->callback((Fl_Callback*)h_scrollbar_cb, this);
-  mHScrollBar->type(FL_HORIZONTAL);
+  shortcut_ = 0;
+  textfont_ = FL_HELVETICA;		// textfont()
+  textsize_ = FL_NORMAL_SIZE;		// textsize()
+  textcolor_ = FL_FOREGROUND_COLOR;	// textcolor()
+  mLineNumLeft = 0;
+  mLineNumWidth = 0;
 
-  end();
-
-  scrollbar_width_ = 0;		// 0: uses Fl::scrollbar_size()
-  scrollbar_align_ = FL_ALIGN_BOTTOM_RIGHT;
-
-  mCursorOn = 0;
-  mCursorPos = 0;
-  mCursorOldY = -100;
-  mCursorToHint = NO_HINT;
-  mCursorStyle = NORMAL_CURSOR;
-  mCursorPreferredXPos = -1;
-  mBuffer = 0;
-  mFirstChar = 0;
-  mLastChar = 0;
-  mNBufferLines = 0;
-  mTopLineNum = mTopLineNumHint = 1;
-  mAbsTopLineNum = 1;
-  mNeedAbsTopLineNum = 0;
-  mHorizOffset = mHorizOffsetHint = 0;
-
-  mCursor_color = FL_FOREGROUND_COLOR;
-
-  mStyleBuffer = 0;
-  mStyleTable = 0;
-  mNStyles = 0;
-  mNVisibleLines = 1;
-  mLineStarts = new int[mNVisibleLines];
-  mLineStarts[0] = 0;
-  for (i=1; i<mNVisibleLines; i++)
-    mLineStarts[i] = -1;
-  mSuppressResync = 0;
-  mNLinesDeleted = 0;
-  mModifyingTabDistance = 0;
-
-  mUnfinishedStyle = 0;
-  mUnfinishedHighlightCB = 0;
-  mHighlightCBArg = 0;
-
-  mLineNumLeft = mLineNumWidth = 0;
-  mContinuousWrap = 0;
-  mWrapMarginPix = 0;
-  mSuppressResync = mNLinesDeleted = mModifyingTabDistance = 0;
   linenumber_font_    = FL_HELVETICA;
   linenumber_size_    = FL_NORMAL_SIZE;
   linenumber_fgcolor_ = FL_INACTIVE_COLOR;
   linenumber_bgcolor_ = 53;	// ~90% gray
   linenumber_align_   = FL_ALIGN_RIGHT;
   linenumber_format_  = strdup("%d");
+
+  // Method calls -- only AFTER all members initialized
+  color(FL_BACKGROUND2_COLOR, FL_SELECTION_COLOR);
+  box(FL_DOWN_FRAME);
+  set_flag(SHORTCUT_LABEL);
+
+  end();
 }