Textmode IDE development

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See also Textmode IDE for more user-oriented hints, and go32v2 development for hints about the particular dos problems of the IDE.

General problems

While the obvious task for the textmode IDE is of course fixing several or some of the 80 bugs, some other stuff comes to mind as future projects. Nearly all have to do with the fact that the IDE effectively stopped evolving significantly since 1.0 times. A lot of problems and ugliness lies in the TP/DOS legacy from this period:

  • the fact that it uses Dos, rather than Sysutils for its filename operations.
    • now that the compiler uses sysutils mostly, the DOS versions are the less tested ones.
    • the fact that shortstrings (or parts of them) are used for filenames.
    • under windows there is no support for unc-paths
  • Even the shortstring filename handling is far from perfect, since the IDE clearly hasn't had the end-user testing for *nix targets that dos/win32 had. Grepping for fixfilename() might yield such problems (like e.g. bug #5614), where filenames are pretty printing, however effectively killing case sensitive filesystems. Bringing this up to ansistring/sysutils level might also help to unify these routines between textmode IDE and Lazarus.
  • Some functionality is deprecated or not active or documented. Examples are browser and code folding (see comments of bug #6696 Some of the functionality mentioned in #11583 might also be "newer"). Note that this kind of functionality is often not finished, e.g. afaik there is no way to save folds. (make them persistent some how). Also the editor components seem to have incremental syntaxhighlighting under ifdef.
  • Another major problem is that the docs have significantly grown. On a PII-233 (128MB and a more recent 20GB disc) it took 20-40 minutes to install the HTML files from the help. Nowadays we have chm support in the FPC tree, maybe it is time to kill all the old helpfile formats and standarize on CHM for a while. (removing the need to have separate files HTML is I think more important than killing e.g. .tph) Initial CHM support added to trunk See the separate section about this topic.
  • On *nix, terminals are swiftly adopting UTF-8 as output type. Supporting this, even very minimally (say ISO8859-1+linedrawing) will be a quite complex task. Required FV rewrite is done as of February, 2022.


In the past the Textmode IDE was compatible with lots of compilers and platforms that are dead. This compatibility has not been maintained/tested for close to a decade, so it is doubtful it works at all. So IMHO it can be removed, and dependencies on things like sysutils are no longer forbidden.


Since FV has reduced in meaning, maybe it can be modernised using the delphi model a bit (streaming and constructors/destructors). I know this is heresy, but a tpobj version could continue to exist. It is mainly for the IDE. I also don't know if it is worthwhile at all (most notably if FV exploits the static nature of objects...).

Maybe a good first approximation would be to try to introduce ansistring everywhere. (Florian has said he has tried this in the past, but that he got stuck. I did an attempt and also got stuck.)

I did a real minor attempt to kill some redundant string routines, but are stuck with the fact that one can't import sysutils into a major TV or IDE because that will cause incompatibilities due to the pstring type. (which is defined both by TV as by sysutils). This is probably the reason why wutils wraps so many sysutils routines, together with the fact that cross-unit overloading seems a bit ambiguous if the relevant parameter types are convertible to eachother (e.g. shortstring and ansistring, or char) It would be major FV re-engineering, and a significant loss of backwards compatibility to fix this. )

It could be easily remedied by reworking TV/IDE to use a "pshortstring" everywhere, which is still compatible with pstring for backwards compatibility as long as sysutils isn't added.

A second stage would replace all path related strings by ansistrings.

For this it is also interesting to look at the C++ version, since there some features only more recently introduced to pascal are added (operator overloading, generics). However a new codebase doesn't have to strictly follow C++, since FPC has certain features that are useful (open arrays, arrays of const, dyn arrays) too.

note: it seems that (static) TP objects are not initialized/finalized. Using ansistrings with them is thus hazardous. Heap TP objects seem to be initialized/finalized. Fixed by Sergei r16632,16635

Chm Support

The chm support was mainly meant to remedy the defects of the loose html based help; mostly install time, HD size (fragmentation, uncompressed) the fact that indexing must be done on the fly, and the constant little problems with filenames in generated HTML files.

Extract the loose HTML help on a Athlon XP2000 takes 8 minutes, and creating the index another 5. CHM reduces this to effectively zero, and adds the full text search capability. On the P-II 233MHz that I occasionally use for DOS testing, times can be over an hour on plain dos.

The CHM support has been in the IDE since 2.2.4, and most seems to be working. Sometimes the html generation from the latex documents has problems, but strictly speaking that is not a chm problem

The LaTeX docs used to be a problem, but recently there has been progress in this department, see Chm backend for fpdoc, latex part. Other improvements to be done:

  • Links over CHM file boundaries still have to be fixed, this is needed for an effective main page. I already have created a simple main page that works in Windows. (and can generate it) (done an initial implementation)
  • installation into the IDE by the installer. (done but not properly installed yet)
  • Index majeur?
  • index for latex pages. (done for ref archive from ref.kwd)
  • preparing the main index takes several seconds on a XP 2000+, specially with LCL.chm installed. Might be annoying on slow computers. Cache? It might also be that the index collection, suffers from the inserted sorting dimensioning problem. (tcollections and tlist are both one big array of pointers. (Ordered) Inserting in such an large array requires a lot of fields to move to make room )
  • there are problems with labels. E.g. from the main TOCs. For now they are stripped, but maybe first labels should be tried, and only then revert to main page.
  • The ref/user/prog chms are in UTF-8 which is not nice for the textmode IDE. (fixed in +/- 2.4.0, there might be detail bugs left though)

CHM boundaries problem

This problem is partial to a deeper problem in the textmode IDE. The way a help page/topic is identified in the textmode IDE is by two (16-bit?) integers. One is the fileid, the other is the topicid in the file.

HTML and CHM's however work string based. IOW a string for file, and a string for the topic (combination of path/file#label). This is solved by allocating a fileid for each chm dynamically onload, and similarly for the topic files. The html subsystem maintains a links-in-current topic cache, and the indexes into that cache act as topicids. (in other wpords a bit dynamic, not all URLs in the chm have one).

However since helpfiles are loaded on a need-to basis, and one might encounter a link to a.chm/path/file in another chm before a.chm is loaded, making it hard to resolve the IDs. This is currently solved by having a registry of CHM files as a global. However that totally bypasses the central helpsystem.

The plain HTML help didn't suffer from this because they cheated: all HTML must be installed in one directory, and links are fixed in the HTML itself. (refer to hardcoded paths ../prog/) So the entire HTML became one big helpfile in practice. Which is fine as a hack, but not really nice or reproducible for other formats.

A minor rewrite that changes the identification to something else (a record with both string and topic id's?) is a possibility, but for that I must first dig up examples of all helpfile types supported and test how they work.

Files of the IDE

Here a short list of the units in the IDE, and their contents. A rough size in kb is added to indicate the relative size of the unit.

Unit Size Remark
fp 14k The main program for the IDE. Parameter processing and a *lot* (400 lines) of initialization.
fpcalc 14k Calculator object for the IDE
fpcatch 6k IDE exception handling.
fpcodcmp 20k Code Complete routines
fpcodtmp 18k Code Template routines
fpcompil 38k Compiler call routines for the IDE
fpconst 17k Constants used by the IDE
fpcygwin 2k Cygwin helpers (versioning, dll name)
fpdebug 103k Debugger call routines for the IDE
fpdesk 29k Desktop loading/saving routines
fpdpansi 3k Unit to export current screen buffer to an ansi file (screendump)
fpevalw 2k Debug expression evaluator dialog ?
fphelp 24k Help routines for the IDE
fpide 72k Main IDEApp object
fpini 24k Write/Read Options to INI File
fpintf 8k Misc routines for the IDE. compiling/running related mostly.
fpkeys 8k Learn keys routines for the IDE
fpredir 19k Unit to redirect output and error to files
fpregs 50k (cpu)Register debug routines for the IDE
fpswitch 49k Compiler switches routines for the IDE
fpsymbol 58k Symbol browse support routines for the IDE
fptemplt 7k Template support routines for the IDE
fptools 47k Tool (menu) support for the IDE
fpusrscr 41k User screen support routines
fputils 11k Utilility routines used by the IDE. Path/file/string related mostly.
fpvars 5k Global variables for the IDE
fpviews 131k Views and view-related functions for the IDE
pmode 6k Support routines for DPMI programs (dos support)
vesa 20k VESA (graphmode switching) support routines
wansi 28k ANSI support
wcedit 58k Code editor template objects
wchmhwrap 5k Chm wrapper. CHM reader parts that deal with classes, to obtain a clean TV - Delphi model separation
wconsole 2k Contains some routines that save/restore console state when executing built programs.
wconsts 0k Strings for common utilities. A handful of numeric consts, and a big includefile with textual constants (localisation?)
weditor 208k Code editor template objects
whelp 27k Help support & Borland OA .HLP reader objects and routines (the latter are moved to woahelp?)
whlpview 41k Help display objects. The base widgets for the help system (?)
whtml 30k base object definitions for html help?
whtmlhlp 43k Main html parser. (for separate html files, and the base of .chm support)
whtmlscn 28k HTML scanner objects
winclip 5k Functions that wrap the windows clipboard for Dos and Windows
windebug 4k Helper functions for use of GDB under Windows. cygdrive + update of running program's windowtitle.
wini 12k Ini file using TP objects
wnghelp 13k Help support for Norton Guide (.NG) files
woahelp 15k Borland OA .HLP reader objects and routines
wos2help 19k Help support for OS/2 (.INF) help files
wresourc 22k (TP?) Resource File support objects and routines
wtphwrit 7k Routines to create .tph files
wutils 32k Utils, mostly collections, string routines and file(name/path) routines.
wviews 69k Enhanced View s(widgets) (special for IDE?)
wvphelp 4k Help support for (.VPH) help files
wwinhelp 49k Help support for Windows Help (.HLP) files
compunit 0k (compiler/ dir) build unit for the compiler.
gdbcon 2k (fakegdb/) fake gdb controller unit to be used when no gdb support is included
gdbint 5k (fakegdb/) fake gdb controller unit to be used when no gdb support is included

Some functionality seems to be split between a w* unit and a fp* unit. (wini,fpini, wviews, fpview). Possibly this is an artifact of an older division between reusable and non reusable units. The fact that there are multiple utility units is also a bit of an indicator for this.

If you know/find out what the criteria for it is, please add it here. If you find out something about a certain unit, make a link out of it prefixed with fv: (see the wutils example).

Besides units, there are also a bunch of include files, most of which seem to be part of fpide, and group routines according to menu category (file, edit, compile etc)

Unit Size Unit Remark
empty.inc 0k test Part of IDE testproject, not IDE itself.
fpmansi.inc 4k fpide Ansi dump capability
fpmcomp.inc 4k fpide Compiler menu entries
fpmdebug.inc 8k fpide Debug menu entries
fpmedit.inc 4k fpide Edit menu entries (one proc only)
fpmfile.inc 8k fpide File menu entries
fpmhelp.inc 12k fpide Help menu entries
fpmopts.inc 48k fpide Options menu entries
fpmrun.inc 16k fpide Run menu entries
fpmsrch.inc 8k fpide Search menu entries
fpmtools.inc 12k fpide Tools menu entries
fpmwnd.inc 8k fpide Window menu entries
globdir.inc 4k MANY IDE project wide defines, included in 19 files.
wconstse.inc 8k wconsts English constants.
wconstsh.inc 4k wconsts Hungarian constants.

Classchart of objects + FV + IDE

An improvised classchart (objectchart?) of all code containing TP style objects ( unit objects, FV and the IDE source) is available here: Object Chart (Postscript view with GV) or pdf version, less often updated

Debugging the IDE

Note that the methods describe here are mostly for *nix.

With GDB tty

Normally one would debug the IDE as follows (Unix)

Terminal Window 1:


Example output:


Terminal Window 2:

gdb ./fp
tty /dev/pts/5

The tty command should then reroute all I/O to tty /dev/pts/5 (Terminal window 1), leaving Terminal Window 2 free to communicate with GDB.

Unfortunately, due to the special keyboard support of the textmode IDE (to capture all CTRL-ALT variants) input is not properly rerouted. This means you can debug IDE startup (and more if you save state smartly), but not the normal working. This method is mainly useful when debugging the start of the IDE.

With GDB attach

This method works better if you want to debug after the IDE has start up.

Terminal Window 1:

Run the IDE from the command line, and wait till it has start up.  

Terminal Window 2:

Find the PID of the running IDE In window 1 using ps aux |grep fp
Start gdb with the correct "fp" file (the one that is running!)
Type attach <pid> on the GDB cmdline
Note that gdb will immediately break upon attach. If you want to carry on, type "c" (continue)

Writeln like

While developing the CHM package I needed to debug browsing also. For this, at first I simply wrote to stderr, and pipe the output to a different terminal (using bash as shell)

Terminal Window 1


Example output:


Terminal Window 2

./fp 2> /dev/pts/5

However, while this would work, it seems sometimes buffering is a problem. Adding a flush would help, but then you have to go after all those writelns again. So it is better to extract it to a procedure. Such a procedure already existed in wutils, and I enhanced it a bit. There are two versions now. "DebugMessage" is the old one, and DebugMessageS is the new one.

To avoid any garbage on the cmdline, all debug messages are always placed under IFDEF. Historically the define "DEBUG" was used for it, but apparantly this is also used in the compiler, and a broken debug feature in the compiler breaks debugging the IDE this way. So I use WDEBUG (mostly in whtmlhlp). The typical debug code fragment then becomes:

  DebugMessageS({$i %file%',' Adding Name "'+Name+'"',%line%,'1');
{$endif WDEBUG}

Note that we use a compiler feature to fill in filename + linenumber for us.

On Windows:

fp.exe 2> logme.txt

Exceptions to stderr

When debugging the IDE, I often change the RTL to log errors to stderr instead of stdout, since stderr is logged using the above 2> redirects, I use the following patch:

 --- sysutils/sysutils.inc       (revision 12440)
 +++ sysutils/sysutils.inc       (working copy)
 @@ -234,7 +234,7 @@
    i : longint;
    hstdout : ^text;
 -  hstdout:=@stdout;
 +  hstdout:=@stderr;
    Writeln(hstdout^,'An unhandled exception occurred at $',HexStr(PtrUInt(Addr),sizeof(PtrUInt)*2),' :');