TweetFollow Us on Twitter

Template Application
Volume Number:1
Issue Number:2
Column Tag: C Workshop

“Template” Application

By Robert B. Denny

This month’s C Workshop presents a “template” application. Most Macintosh programs share a common overall structure, dictated by the operating system environment. The purpose of the template program is to give you a framework for developing your own applications. It will also be used as the basis for topics discussed in future C Workshops. The functions that do the actual work of the program have been “stubbed”.

Since “a program is worth a thousand words”, most of this month’s column is the program itself, sprinkled liberally with comments. Please take the time to study the program. But first, a few introductory words.

Some C Basics for the Macintosh

Many data structures that you’ll be working with are stored in the “heap”, dynamic memory. Most of these struc- tures are accessed by a “handle” rather than a pointer. A handle is a pointer to a pointer. Why this extra level of indirection?

The heap is used for almost everything. Code goes there. Resources go there (code is really a resource). Data structures allocated at run time go there. Nothing is preallocated. The memory manager is rather dumb about allocating and deallocating blocks of space in the heap.

As a result, the heap can (and does) get chopped up into small pieces. When someone makes a request for a block of space that exceeds the size of the largest free block, the memory manager compacts the heap. It moves blocks of data around in an effort to collect enough contiguous space to satisfy the request. Blocks that are eligible to be moved are called relocatable. Most Mac data structures fall into this class. You can control whether or not your own data structures are relocatable. The tradeoff should be obvious.

Relocatable data structures are accessed via handles so that your references remain valid if the structure is moved. The handle points to a master pointer which in turn points to the relocatable structure. If the structure is moved, the memory manager updates the master pointer and your handle reference remains valid. Obviously, the area containing the master pointers is not relocatable.

Accessing data structures defined by struct statements via handles isn’t too difficult. The example is shown in figure 1 below:

The expression assigns the value contained in the relocatable structure via its handle to “intval”. The only safe way to access relocatable structures is to use the double-indirect access shown above at all times. Do not attempt to cache the pointer (*foo_handle) at any time. To do so is to defeat the purpose of handle access.

Template Application

Now to the template application. It is written for the Consulair Mac C system and Toolkit. Changes to the details of the program will probably be necessary for other languages since there is little consistency in the toolbox interface.

/*
 * *************
 * *  TEMPL.H  *
 * *************
 *
 * Common stuff for template program
 *  (C) 1984, MacTech  by Robert B. Denny
 *
 * NOTE:Dependent on the menu                 
 *   structure defined in the resources.
 */

// Toolbox traps must start with ‘#’ now.
#Options -N

//
// Include Macintosh data structure 
// definitions.  These files are included 
// with the Mac C Toolkit, or from the 
// Stanford University Macintosh C 
//  Programming system (SuMacC).
//

#include  <MacDefs.H>
#include<QuickDraw.H>
#include<Control.H>
#include<Events.H>
#include<Menu.H>
#include<TextEdit.H>

#define MAX_WINDOWS8
#define MAX_MENUS8

#define TRUE1
#define FALSE    0
#define NULL0

/*
*  Each window requires a window                
*  control block to define it’s structure. 
*  Note which things are handles and           
*  which are pointers.
*
* wcb = Window Control Block
 */
struct wcb
 {
 WindowPtrwp;  // Pointer to window rec in heap
 Rect drag_rect; // Dragging limits
 Rect grow_rect; // Window size limits
 TEHandle te_handle; // Handle to textEdit rec in heap
 Point  te_origin; // Text origin
 ControlHandle vs_handle; // Vert scroller’s handle
 ControlHandle hs_handle; // Horiz scroller’s handle
 };

//
// Supress extern declarations in module 
// containing the real declarations.
//
#ifndef GLOB_DATA
extern struct wcb dw[MAX_WINDOWS];
extern struct wcb *dwp;   // --> Current doc-window
extern unsigned n_windows;// No. of open windows
extern EventRecord Event; // Our event record (duh)
extern short EvType; // Event result type
extern WindowPtr EvWindow;// Event window
/*
 * Array of menu handles 
 */
extern MenuHandle menus[];// Our menu contexts
#define APPLE    1
#define FILE2
#define EDIT3
#define OPTIONS  4
#endif

/*
 * Resource ID’s of menus in rsrc file.
 */
#define APPLE_ID 1
#define FILE_ID  256 
#define EDIT_ID  257
#define OPTIONS_ID 258 //Add more menu resource ID’s here

/*
 * File menu item numbers
 */

#define FM_EXIT  // This should reflect file menu rsrc

/*
 * Edit menu item numbers
 *
 * Note that SystemEdit expects the Edit    
 *  menu items as follows:
 *
 * 0: undo (** YES, zero-based **)
 * 1: --------
 * 2: cut 
 * 3:  copy
 * 4: paste
 *
 * The rest of the items may be chosen 
 *    at will by the application.
 */

#define EM_UNDO  1
#define EM_CUT 3
#define EM_COPY  4
#define EM_PASTE 5
#define EM_CLEAR 6

/*
 * Options menu assignments
 */
#define MM_EDIT_WINDOW  1
#define MM_SCRAWL_WINDOW  2
#define MM_MUSIC  4

/*
 *   Other resource ID’s
 */
#define ABOUT_ID 256
#define WINDOW_ID256

/*
 * Macro to hack the Point struct,               
 * composed of 2 short (16-bit) ints
 * into a long, which can be passed by         
 * value to toolbox routines.
 * Takes address of a Point and turns it      
 * into a scalar long.  NOTE
 * this generates NO runtime code.
 */
#define PtLong(ptr) *((long *)ptr)

MAIN PROGRAM

A Template Application in C

Template program for the C Workshop. Has hooks for multiple dynamically allocated windows (to be added in future columns), supports desk accessories, has a menu bar with 4 menus and an “about” dialog in the Apple menu. The program will eventually support multiple dynamically allocated text edit and drawing windows. The text edit windows will have scroll bar controls and resizing (“grow”) capability. Also, an interface to the sound system will be added. The components of this program are:

TMAIN.C This module, the main program & global data.

TMENU.C Menu handling functions, fig. 6.

TEMPL.H Common “include” file of definitions, fig. 4.

TEMPL.R RMAKER source for program resources, fig. 5.

TEMPL.LINK Linker command file, fig. 3.

TEMPL.JOB Exec command procedure to build template, fig. 2.

Additional modules will be added in future C Workshop columns. This program was written for the MAC C system by Consulair Corp. Changes will be needed for other C systems. Also, prerelease versions of MAC C and RMAKER may not work with this program. [Note: one or two obscure Mac C statements may have been changed in the current Mac C so that a change may be needed to fully compile this program using present Mac C systems. This program was written with an early version of Mac C. Any offending lines should be obvious at compile time. -Ed.]

/*
 * TMAIN.C - Template application
 * (c) 1984 MacTech by Robert B. Denny
 */
 *     GLOBALS DEFINITIONS
#define GLOB_DATA
#include <Templ.H>
/*
 Define window control block for window   management. See Templ.H file.
 */
struct wcb dw[MAX_WINDOWS];  // our windows
struct wcb *dwp = NULL; // --> Current window
unsigned n_windows = 0; // Number of open windows
EventRecord Event; // Our event record
short EvType;    // Event result type
WindowPtr EvWindow;// Event window
MenuHandle menus[MAX_MENUS]; // Our menus
 
/*
 *   MAIN PROGRAM  
 *
 * Link with MacCLib, which does 
 * Quickdraw and Window initialization.
 *
 */
main()
 {
 register WindowPtr wp; // Try to save space/time
 int i;
 #InitFonts();   // Not done in MacCLib ...
 #InitDialogs(0);// No restart function
 #OpenResFile(“\011TemplRsrc”);// Open resfile (Pstring)
 setup_menu();   // Set up our menus
 #TEInit(); // Initialize TextEdit
 #FlushEvents(-1,0); // Flush all events
 #InitCursor();  // Make arrow cursor
 for(i=0; i<MAX_WINDOWS; i++) // Mark all WCB’s free
 dw[i].wp = NULL;
 dwp = NULL;// No windows
 n_windows = 0;

 //   -- EVENT LOOP --
 // This is the “outer loop” of a typical    // application.  All event 
types
 // are dequeued, most are processed.  // Those not processed are ignored.
 // 
 while(TRUE)// Loop here forever
 {
 #SystemTask();  // Handle desk accessories
 // dwp always points to the WCB   //for the active (front) window.
 // If dwp = NULL, than it’s not   //”our” window.
 // (Is this possible??)

dwp = (struct wcb *)find_wcb(#FrontWindow());
if(dwp != NULL && dwp->te_handle != 0) // If active wind & text
#TEIdle(dwp->te_handle);  // Flash the insertion mark
if(!#GetNextEvent(-1, &Event)) // Process only our events
continue;
 switch(Event.what)// Dispatch on event type
 {
 case mouseDown: // Mouse click
 do_mouse();// Dispatch on mouse location
 break;
 case keyDown: // Keypress
 case autoKey:  // Repeat-key generator
 do_key();
 break;
 case updateEvt: // window needs refresh
EvWindow = (WindowPtr)Event.message; // Which window?
 upd_wind(EvWindow); // Do the update
 break;
 case activateEvt: // Activate/deactivate
EvWindow = (WindowPtr)Event.message; // Which window?
 if(Event.modifiers & 1) // If Activate
 act_wind(EvWindow); // Activate window
 else // If Deactivate
 deact_wind(EvWindow); // Deactivate window
 
// Additional cases for other event types 
 default: // Do nothing for other events
 }
 }
 //
 // -- END OF EVENT LOOP --
 //
 }

/*
 * *  LOCAL FUNCTIONS  *
 *     Handle mouse-down events
 */
do_mouse()
 {
 short window_part;// FindWindow result code //
 // Following fills in EvWindow with //--> window in which the click
 // occurred (or NULL if none).
 //
 window_part = #FindWindow(PtLong(&Event.where), &EvWindow);
 
 switch(window_part) // Dispatch on where clicked
 {
 case inMenuBar: do_menu(#MenuSelect(PtLong(&Event.where))); 
 break;
 case inSysWindow:
 #SystemClick(&Event, EvWindow);
 break;
 case inContent: // Click in content of a window
 #SelectWindow(EvWindow); // Activate window
 #SetPort(EvWindow); // Hook QuickDraw up
 break;
 case inDrag:
 #SelectWindow(EvWindow); // Activate 
 #SetPort(EvWindow); // Hook QuickDraw up 
 break;
 case inGoAway:  // Go-away handling
 break;
 case inGrow:  // Grow handling
 break;
// Add dispatches for other area types
 default:
 }
 }

/*
 *  - Handle keypress and command keys
 *     Handles edit command keys 
 */
do_key()
 {
 unsigned short ch;
 ch = (unsigned short)Event.message; // Isolate key codes
 if(Event.modifiers & cmdKey) // If command character
 do_menu(#MenuKey(ch)); // Try menu shortcut cmd
 }
// Stub functions
upd_wind(wp)
WindowPtr wp;
 {
 return(0);
 }
act_wind(wp)
WindowPtr wp;
 {
 return(0);
 }
deact_wind(wp)
WindowPtr wp;
 {
 return(0);
 }
find_wcb(wp)// Never one of our windows
WindowPtr wp;
 {
 return(0);
 }

MENU SUB-PROGRAM IN C

/*
 * TMenu.C - Handle menu selections for 
 * template program
 *
 *  (c) 1984, MacTutor  by Bob Denny
 */
#include<Templ.H>
/*
 * SETUP_MENU() - Initialize menu system 
 *
 * Fills in an array of menu handles.  Not     
*  used in this version of the program. 
 */
setup_menu()
 {
 #InitMenus();
 #InsertMenu(menus[APPLE] = (MenuHandle)#GetMenu(APPLE_ID), 0);
 #AddResMenu(menus[APPLE], ‘DRVR’);
 #InsertMenu(menus[FILE] = (MenuHandle)#GetMenu(FILE_ID), 0);
 #InsertMenu(menus[EDIT] = (MenuHandle)#GetMenu(EDIT_ID), 0);
 #InsertMenu(menus[OPTIONS] = (MenuHandle)#GetMenu(OPTIONS_ID), 0);
 #DrawMenuBar();
 }
 
/*
 * DO_MENU() - Handle menu selection
 *
 * Input:
 * Result longword from MenuSelect       
 *        or MenuKey
 */
do_menu(result)
unsigned result;
 {
 unsigned short menu_id; // Resource ID of selected menu
 unsigned short item_no; // Item number selected
 char item_name[64]; // Item name (for desk acc.)
 Ptr dp;// Dialog pointer for “about ...”
 unsigned short item_hit; // Dialog item that was hit 
 if(result == 0) // Just for safety with MenuKey
 return;// Ignore zero results
 menu_id = (short)#HiWord(result); // Use toolbox 
 item_no = (short)#LoWord(result);
 
 switch(menu_id)
 {
 case APPLE_ID: // “Apple” menu
 if(item_no > 1) // If desk accessory
 {
 #GetItem(menus[APPLE], item_no, item_name);
 #OpenDeskAcc(item_name);
 }
 else  // Our About ... dialog
 {
 dp = #GetNewDialog(ABOUT_ID, 0, -1); 
 // Bring in dialog to front
 #SetPort(dp); // Hook QuickDraw up to dialog
 #ModalDialog(0, &item_hit); // dialog item hit
 #DisposeDialog(dp); // Close & free heap 
 }
 break;

 case FILE_ID: // File menu
 if(item_no == FM_EXIT)
 #ExitToShell(); // Ugly exit
 break;
 
 case EDIT_ID:
 //
 // First we must hand off any   // desk-accessory edit commands.
 // Note the comments in Demo.H 
 // regarding implicit assumptions
 // in numbering items in Edit menu.
 //
 if(#SystemEdit(item_no - 1)) // Relies on item no.!!
 break;
 //
 // Do the requested edit function only      // if this is an editing 
window and there // is a window open.  For now, we have  // no windows, 
so we just return.
 //
 break;
 
 case OPTIONS_ID: // Options menu.
 switch(item_no)
 {
 case MM_MUSIC:
 play_tune();
 break;
 case MM_EDIT_WINDOW:
 edit_window();
 break;
 case MM_SCRAWL_WINDOW:
 scrawl_window();
 break;
 
 default:
 }
 break;
 
 default:
 }
 #HiliteMenu(0); // Turn off highlighted title
 }
// Stub functions
play_tune() // Make crude music -- demo driver 
 {
 return(0);
 }
edit_window()  // Create a new editing window
 {
 return(0);
 }
scrawl_window()  // Create a new “scrawling” window
 {
 return(0);
 }

Resource File

This is the RMAKER source for the Mac C template application. The dialog box will not come out right with the version of the RMAKER that I have. The \0D entries in the staticText item are supposed to be “hard” carriage returns in the text. Instead, they come out as “D”. To fix this, use the AlertDialog Editor on the file after building it to put the 2 carriage returns in and remove the “D”s. Perhaps RMAKER (or it’s successor) will work some day ...

The menu items for things that aren’t in the template (yet) have been dimmed. As things are filled in, you’ll have to edit this file to un-dim & thus activate the corresponding menu items. Note that the Edit menu is enabled to support SystemEdit editing in desk accessories.

* Templ.R  --  Resources for the 
*                     template program
*
*  (C) 1984, MacTech by R. B. Denny 

TemplRsrc
RSRCXXXX

TYPE WIND
  ,256
Please Wait ...
50 50 250 250
Visible GoAway
0
0

TYPE MENU
  ,1
\14
About Template ...
(-

  ,256
File
Quit

  ,257
Edit
(Can’t Undo
(-
Cut/X
Copy/C
Paste/V
Clear/D

  ,258
Options
(New Edit Window
(New Scrawl Window
(-
(Play a tune

TYPE DLOG
  ,256

54 145 203 376
Visible NoGoAway
1
0
256


TYPE DITL
  ,256
2

button
116 58 142 174
RESUME DEMO

staticText Disabled
9 9 105 228
This program was written as an example of native Macintosh ++ 
application programming in the C language, using Mac C. 
\0D \0D ++ 
Bob Denny            October, 1984

 
AAPL
$103.30
Apple Inc.
+0.80
MSFT
$45.09
Microsoft Corpora
-0.34
GOOG
$577.33
Google Inc.
+5.73

MacTech Search:
Community Search:

Software Updates via MacUpdate

TextSoap 7.4.0 - Flexible text editing u...
TextSoap is for people who work with text. TextSoap effortlessly cleans up text from endlessly different formats. Wash away unwanted characters, spaces, tabs. Fix paragraphs with hard returns at the... Read more
NetShade 6.0.2 - Browse privately using...
NetShade is an Internet security tool that conceals your IP address on the web. NetShade routes your Web connection through either a public anonymous proxy server, or one of NetShade's own dedicated... Read more
Mac DVDRipper Pro 5.0 - Copy, backup, an...
Mac DVDRipper Pro is the DVD backup solution that lets you protect your DVDs from scratches, save your batteries by reading your movies from your hard disk, manage your collection with just a few... Read more
pwSafe 3.1 - Secure password management...
pwSafe provides simple and secure password management across devices and computers. pwSafe uses iCloud to keep your password databases backed-up and synced between Macs and iOS devices. It is... Read more
StatsBar 1.8 - Monitor system processes...
StatsBar gives you a comprehensive and detailed analysis of the following areas of your Mac: CPU usage Memory usage Disk usage Network and bandwidth usage Battery power and health (MacBooks only)... Read more
Path Finder 6.5.5 - Powerful, award-winn...
Path Finder is a file browser that combines the familiar Finder interface with the powerful utilities and innovative features. Just a small selection of the Path Finder 6 feature set: Dual pane... Read more
QuarkXPress 10.2.1 - Desktop publishing...
With QuarkXPress, you can communicate in all the ways you need to -- and always look professional -- in print and digital media, all in a single tool. Features include: Easy to Use -- QuarkXPress is... Read more
Skype 6.19.0.450 - Voice-over-internet p...
Skype allows you to talk to friends, family and co-workers across the Internet without the inconvenience of long distance telephone charges. Using peer-to-peer data transmission technology, Skype... Read more
VueScan 9.4.41 - Scanner software with a...
VueScan is a scanning program that works with most high-quality flatbed and film scanners to produce scans that have excellent color fidelity and color balance. VueScan is easy to use, and has... Read more
Cloud 3.0.0 - File sharing from your men...
Cloud is simple file sharing for the Mac. Drag a file from your Mac to the CloudApp icon in the menubar and we take care of the rest. A link to the file will automatically be copied to your clipboard... Read more

Latest Forum Discussions

See All

Modern Combat 5 Gets a Major Multiplayer...
Modern Combat 5 Gets a Major Multiplayer Update Posted by Jessica Fisher on September 2nd, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Alien Creeps TD Review
Alien Creeps TD Review By Jennifer Allen on September 2nd, 2014 Our Rating: :: EXPENSIVE DEFENSESUniversal App - Designed for iPhone and iPad Alien Creeps TD would be a fun if unremarkable Tower Defense game, but its heavy focus on... | Read more »
The Journey Down: Chapter Two Review
The Journey Down: Chapter Two Review By Jennifer Allen on September 2nd, 2014 Our Rating: :: DARK YET ENTICINGUniversal App - Designed for iPhone and iPad It’s a little dark, in every sense of the word, but The Journey Down:... | Read more »
Function Space, a Social Network App for...
Function Space, a Social Network App for Science, Launches on iOS Posted by Ellis Spice on September 2nd, 2014 [ permalink ] | Read more »
Stupidfast – How Taylor Martinez Switche...
How do you make an Endless Running game more than just another Endless Running game? By adding real life prizes to it, of course! That’s the thinking behind StupidFast: a game designed for football enthusiasts, and the brainchild of former college... | Read more »
Little Raiders: Robin’s Revenge Review
Little Raiders: Robin’s Revenge Review By Jennifer Allen on September 2nd, 2014 Our Rating: :: CASUAL RAIDINGUniversal App - Designed for iPhone and iPad Combining simple combat with village building is a potent combination for... | Read more »
Treasure Tombs: Ra Deal Coming from Bulk...
Treasure Tombs: Ra Deal Coming from Bulkypix and Dark Tonic This Fall Posted by Jessica Fisher on September 2nd, 2014 [ permalink ] Dark Tonic and | Read more »
Pirate Bash Review
Pirate Bash Review By Nadia Oxford on September 2nd, 2014 Our Rating: :: BAD PIRATES, GOOD TIMESUniversal App - Designed for iPhone and iPad Pirate Bash’s turn-based battles add an intriguing twist to a typical physics game.   | Read more »
Tiny Tower Vegas Review
Tiny Tower Vegas Review By Jennifer Allen on September 2nd, 2014 Our Rating: :: STEADY DEVELOPMENTUniversal App - Designed for iPhone and iPad Build a huge tower again but Vegas-style in Tiny Tower Vegas.   | Read more »
The Manhattan Project Review
The Manhattan Project Review By Andrew Fisher on September 2nd, 2014 Our Rating: :: ROCKET SCIENCEUniversal App - Designed for iPhone and iPad The Manhattan Project offers a great Euro-style gameplay experience, but it is totally... | Read more »

Price Scanner via MacPrices.net

Apple refurbished iPads available for up to $...
Apple is offering Certified Refurbished iPad Airs for up to $140 off MSRP. Apple’s one-year warranty is included with each model, and shipping is free. Stock tends to come and go with some of these... Read more
Are We Now In The Post-Post-PC Era?
A longtime and thoroughgoing laptop aficionado, I was more than a little dismayed by Steve Jobs’s declaration back in 2010 when he sprang the iPad on an unsuspecting world. that we’d entered a “post-... Read more
PC Outlook Improves, But 2014 Shipments Still...
According to the International Data Corporation (IDC) Worldwide Quarterly PC Tracker, worldwide PC shipments are expected to fall by -3.7 percent in 2014. To hat’s actually an improvement from the... Read more
IDC Lowers Tablet Sales Projections for 2014...
Following a second consecutive quarter of softer than expected demand, International Data Corporation (IDC) has lowered its worldwide tablet plus 2-in-1 forecast for 2014 to 233.1 million units. The... Read more
Apple now offering refurbished 21-inch 1.4GHz...
The Apple Store is now offering Apple Certified Refurbished 21″ 1.4GHz iMacs for $929 including free shipping plus Apple’s standard one-year warranty. Their price is $170 off the cost of new models,... Read more
Save $50 on the 2.5GHz Mac mini, on sale for...
B&H Photo has the 2.5GHz Mac mini on sale for $549.99 including free shipping. That’s $50 off MSRP, and B&H will also include a free copy of Parallels Desktop software. NY sales tax only. Read more
Save up to $300 on an iMac with Apple refurbi...
The Apple Store has Apple Certified Refurbished iMacs available for up to $300 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free. These are the best prices on... Read more
The Rise of Phablets
Carlisle & Gallagher Consulting Group, a businesses and technology consulting firm focused solely on the financial services industry, has released an infographic depicting the convergence of... Read more
Bad Driver Database App Allows Good Drivers t...
Bad Driver Database 1.4 by Facile Group is a new iOS and Android app that lets users instantly input and see how many times a careless, reckless or just plain stupid driver has been added to the... Read more
Eddy – Cloud Music Player for iPhone/iPad Fre...
Ukraine based CapableBits announces the release of Eddy, its tiny, but smart and powerful cloud music player for iPhone and iPad that allows users to stream or download music directly from cloud... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Senior Event Manager, *Apple* Retail Market...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global event strategy. Delivering an overarching brand story; in-store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.