DVX_GUI/loader

DVX Loader

Bootstrap loader for the DVX desktop environment. Builds as dvx.exe -- the only native executable in the system. Everything else is a dynamically loaded DXE module.

What It Does

1. Changes to the executable's directory so relative paths resolve
2. Calls platformRegisterDxeExports() to register platform functions and C runtime symbols (libc, libm, libgcc, DJGPP internals) with the DXE3 loader via dlregsym()
3. Recursively scans LIBS/ for *.lib modules and WIDGETS/ for *.wgt modules
4. Reads .dep files to build a dependency graph
5. Topologically sorts all modules and loads them in order with RTLD_GLOBAL (each module's exports become available to subsequent modules)
6. Calls wgtRegister() on any module that exports it (widget registration)
7. Finds shellMain() across all loaded modules and calls it
8. On return, closes all modules in reverse order

Files

File	Purpose
loaderMain.c	Entry point, directory scanning, dependency resolution, module loading
Makefile	Cross-compilation rules; links dvxPlatformDos.c directly

The DXE export table lives in core/platform/dvxPlatformDos.c, not in the loader. The loader is platform-agnostic -- all DJGPP/DXE3 knowledge is in the platform layer.

Dependency Resolution

Each module may have a .dep file alongside it (same base name, .dep extension). The file lists base names of modules that must be loaded first, one per line. Lines starting with # are comments.

Example -- dvxshell.dep:

libtasks
libdvx
box
button
label
listview

A dependency is satisfied when either:

• A module with that base name has been loaded, or
• No module with that base name exists in the scan (external, assumed OK)

The loader iterates until all modules are loaded or no further progress can be made (circular dependency). Unloadable modules are reported to stderr.

Building

make        # builds ../bin/dvx.exe
make clean

The Makefile compiles loaderMain.c and links it with dvxPlatformDos.o (compiled from ../core/platform/dvxPlatformDos.c) and -lm. The result goes through exe2coff + CWSDSTUB to produce a DOS executable.