compiler-toolchain compatibility pass (permissive stubs, batch/features, Wine/native dispatch)

Makefile

@@ -1,11 +1,11 @@
-.PHONY: all clean run
+.PHONY: all clean run test test-batch test-mem test-cli test-cli-matrix test-static test-sanitizers test-valgrind test-tooling
 .SUFFIXES:
 MAKEFLAGS += -r
 
 ALL = kvikdos guest.com slowp.com malloct.com mallocs.com printenv.com cat.com waitkey.com
 
 # -Werror=int-conversion: GCC 4.8.4 fails.
-CFLAGS = -ansi -pedantic -s -O2 -W -Wall -Wextra -Werror=implicit-function-declaration -fno-strict-aliasing -Wno-overlength-strings $(XCFLAGS)
+CFLAGS = -ansi -pedantic -s -O2 -W -Wall -Wextra -Wuninitialized -Wmaybe-uninitialized -Werror -fno-strict-aliasing -Wno-overlength-strings $(XCFLAGS)
 XCFLAGS =  # To be overridden from the command-line.
 
 SRCDEPS = kvikdos.c mini_kvm.h
@@ -18,6 +18,31 @@ clean:
 run: kvikdos guest.com
 	./kvikdos guest.com hello world
 
+test: test-batch test-mem test-cli test-cli-matrix
+
+test-batch: kvikdos
+	./tests/test_batch.sh ./kvikdos
+
+test-mem: kvikdos
+	./tests/test_mem_services.sh ./kvikdos
+
+test-cli: kvikdos
+	./tests/test_cli_parse.sh ./kvikdos
+
+test-cli-matrix: kvikdos
+	./tests/test_cli_matrix.sh ./kvikdos
+
+test-static:
+	./tests/test_static.sh
+
+test-sanitizers:
+	./tests/test_sanitizers.sh
+
+test-valgrind: kvikdos
+	./tests/test_valgrind.sh ./kvikdos
+
+test-tooling: test-static test-sanitizers test-valgrind
+
 %.com: %.nasm
 	nasm -O0 -f bin -o $@ $<
 

README.txt

@@ -46,9 +46,9 @@ Limitations:
   (last 768 bytes), BIOS Data Area, helper code, the user code written for
   Linux.
 
-  kvikdos doesn't support memory types UMB (up to 384 KiB more), HMA (63
-  KiB more), XMS (up to hundreds of megabytes more) or EMS (also up to
-  hundres of megabytes, overlapping with XMS).
+  kvikdos has partial compatibility support for UMB/XMS/EMS probes and
+  common allocator APIs used by DOS toolchains, but it is not a full
+  memory-manager implementation (no full DPMI/VCPI stack).
 
   If your DOS programs need mre memory, use udosrun or DOSBox instead.
 
@@ -72,6 +72,12 @@ Limitations:
   already work, see the compatibility list below. To get good chances for
   running any random DOS program, use udosrun or DOSBox instead.
 
+* If the target file is Linux-native (ELF or shebang script), kvikdos
+  executes it natively with Linux `fork+execvp` instead of DOS emulation.
+
+* If the target file is a Windows executable format (PE/NE/LE/LX), kvikdos
+  delegates execution to `wine` automatically.
+
 Features and advantages:
 
 * kvikdos is very fast, it runs CPU-intensive code at almost native speeds
@@ -146,6 +152,123 @@ How to install kvikdos:
 
   If it displays the dot and the `Hello, World!' message, then it's OK.
 
+Command-line options (structured):
+
+General:
+
+* `--kvm-check' checks KVM only.
+* `--strict' enables strict unsupported-interrupt behavior.
+* `--permissive' enables compatibility fallback behavior (default).
+
+DOS runtime:
+
+* `--toolchain=<name>' applies toolchain presets:
+  `msc4', `msc5', `msc6', `masm5', `bc2', `bcpp1', `bc5', `ic86'.
+* `--env=<NAME>=<value>' adds one DOS environment variable.
+* `--env-file=<file>' loads DOS environment variables from file
+  (`NAME=VALUE' lines).
+* `--path-dos=<pathlist>' sets DOS PATH explicitly.
+* `--prog=<dos-pathname>' sets DOS pathname of the running program.
+* `--cwd-dos=<path>' sets initial DOS current directory.
+
+Mounts:
+
+* `--mount=<drive><case><dirname>/' mounts Linux directory to DOS drive.
+* `--mount=<drive>0' hides DOS drive.
+* `--drive=<drive>' sets initial DOS drive.
+
+Compatibility:
+
+* `--case-fallback=off|prog|all' controls case-insensitive executable
+  lookup fallback. Default: `all'.
+
+Diagnostics:
+
+* `--diag=compat|exec|int|fs|all|off' controls runtime diagnostics.
+  Default: `compat'.
+* `--diag-file=<file>' writes diagnostics to a file.
+
+I/O and memory:
+
+* `--tty-in=<fd>' chooses input source (`-3', `-2', `-1', `>=0').
+* `--mem-mb=<n>' DOS memory size in MiB (currently only `1').
+* `--hlt-ok' and `--hlt-dump=<file>' are low-level debug options.
+
+Best defaults:
+
+* `--permissive'
+* `--case-fallback=all'
+* `--diag=compat'
+* no toolchain preset unless requested
+
+Examples:
+
+* Microsoft C 5.1:
+
+    $ ./kvikdos --toolchain=msc5 /home/xor/inertia_player/dos_compilers/Microsoft\ C\ v5/CL.EXE HELLO.C
+
+* Borland C 2 with explicit DOS PATH and cwd:
+
+    $ ./kvikdos --path-dos=C:\\ --cwd-dos=C:\\ /home/xor/inertia_player/dos_compilers/Borland\ Turbo\ C\ v2/TCC.EXE HELLO.C
+
+* Diagnostics to file:
+
+    $ ./kvikdos --diag=all --diag-file=kvikdos.diag /home/xor/inertia_player/masm/BIN/LINK.EXE
+
+Batch regression tests:
+
+* Run all local tests:
+
+    $ make test
+
+* Current batch suite (`tests/test_batch.sh`) covers commands/patterns used
+  by DOS compiler scripts: `set`, `%VAR%`, `%1..%9`, `shift`, `call`,
+  `if` (`==`, `not`, `errorlevel`, `exist`), `goto`, `mkdir`, `copy`, `del`.
+
+Static analysis and runtime checks:
+
+* cppcheck:
+
+    $ cppcheck --enable=warning,style,performance,portability --std=c89 --force kvikdos.c
+
+* clang static analyzer:
+
+    $ clang --analyze -Xanalyzer -analyzer-output=text -std=c89 -Wall -Wextra kvikdos.c
+
+* ASan+UBSan build and compiler smoke:
+
+    $ gcc -O1 -g -fsanitize=address,undefined -fno-omit-frame-pointer -fno-strict-aliasing -o kvikdos_asan kvikdos.c
+    $ /home/xor/kvikdos/kvikdos_asan /home/xor/inertia_player/dos_compilers/Microsoft\ C\ v5/CL.EXE /c HELLO0.C
+    $ /home/xor/kvikdos/kvikdos_asan /home/xor/inertia_player/dos_compilers/Microsoft\ MASM\ v5/BIN/MASM.EXE HELLO.ASM,HELLO.OBJ,NUL.LST,NUL.CRF
+
+* Valgrind smoke:
+
+    $ valgrind --tool=memcheck --leak-check=full --error-exitcode=101 ./kvikdos /home/xor/inertia_player/dos_compilers/Microsoft\ C\ v5/CL.EXE /c HELLO0.C
+    $ valgrind --tool=memcheck --leak-check=full --error-exitcode=101 ./kvikdos /home/xor/inertia_player/dos_compilers/Microsoft\ MASM\ v5/BIN/MASM.EXE HELLO.ASM,HELLO.OBJ,NUL.LST,NUL.CRF
+
+Readability and stability improvement roadmap (recommended):
+
+* Priority 1 (safety):
+  * Initialize all state structs (`DirState`, `ParsedCmdArgs`, runtime locals)
+    before first use; avoid partial-init patterns.
+  * Keep parser regression tests for option combinations (`--prog`, mounts,
+    drive/cwd/path interactions) and assert "no crash" behavior.
+  * Prefer bounded copy helpers (`copy_cstr0`) over ad-hoc `strncpy` usage.
+
+* Priority 2 (clarity):
+  * Split large functions (`parse_args`, `run_dos_prog`, `run_dos_batch`)
+    into smaller helpers by responsibility:
+    argument parsing, DOS path translation, int21 dispatch, batch command eval.
+  * Replace ambiguous locals (`p`, `q`, `r`) with intent names in new code
+    (`requested_drive`, `active_drive`, `resolved_prog`).
+  * Keep compatibility fallbacks local and commented at point of use.
+
+* Priority 3 (analysis depth):
+  * Add a fast static target in CI: `cppcheck` + `clang --analyze`.
+  * Add sanitizer targets (ASan+UBSan) and valgrind jobs as separate steps.
+  * Add negative tests for malformed paths/env/flags to verify deterministic
+    error messages and exit codes.
+
 About making Linux files available for DOS programs:
 
 * kvikdos emulates DOS drives A: .. F: by exposing directories on the Linux
@@ -217,6 +340,27 @@ About uppercase and lowercase filenames:
 
 Software compatibility, i.e. DOS programs known to work in kvikdos:
 
+Quick start for DOS compilers and assemblers:
+
+* For practical, copy-paste command lines, see TOOLCHAIN.md in this
+  repository.
+
+* Recommended layout rules:
+  * Use 8.3 filenames for source/object/output files (e.g. HELLO.C).
+  * If a toolchain has BIN/LIB/INCLUDE directories, mount the toolchain
+    root as C: and run the executable from C:\BIN\...
+  * Set DOS environment explicitly with --env=LIB=... and
+    --env=INCLUDE=...
+
+* Recently validated under kvikdos (compile, link, run of a tiny HELLO):
+  * Microsoft C 4.0
+  * Microsoft C 5.1
+  * Microsoft C 6ax (from toolchain root, C:\BIN\CL.EXE, LIB=C:\LIB)
+  * Intel iC-86 Compiler 4.5
+  * Borland Turbo C 2.0
+  * Borland Turbo C++ 1.01 (from toolchain root, C:\BIN\TCC.EXE, LIB=C:\LIB)
+  * Microsoft MASM 5.0 (MASM direct, LINK via prompt answers or stdin)
+
 * Turbo Pascal 7.0 compiler tpc.exe. It produces .exe program files
   directly.
 

TOOLCHAIN.md

@@ -0,0 +1,102 @@
+# kvikdos Toolchain Guide
+
+This document shows known-good ways to run DOS C/ASM toolchains under `kvikdos`.
+
+## Key rules
+
+- Use DOS 8.3 names for source/object/output files when possible.
+- Mount the correct directory as `C:` with `--mount=C:.` from that directory.
+- For toolchains with separate `BIN`, `LIB`, `INCLUDE`, mount their parent root and call executables as `C:\BIN\...`.
+- Set `LIB` and `INCLUDE` explicitly with `--env=...`.
+
+## Minimal C source
+
+Use this for widest compatibility:
+
+```c
+main(){return 0;}
+```
+
+## Microsoft C 4.0
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Microsoft C v4'
+printf 'main(){return 0;}\n' > HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=lib --env=INCLUDE=inc C:\CL.EXE /c HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=lib C:\LINK.EXE HELLO,,,SLIBFP
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Microsoft C 5.1
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Microsoft C v5'
+printf 'main(){return 0;}\n' > HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=lib --env=INCLUDE=inc C:\CL.EXE /c HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=lib C:\LINK.EXE HELLO,,,SLIBCE
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Microsoft C 6ax
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Microsoft C v6ax'
+printf 'main(){return 0;}\n' > HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=C:\LIB --env=INCLUDE=C:\INCLUDE C:\BIN\CL.EXE /c /AS HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=C:\LIB C:\BIN\LINK.EXE HELLO,,,SLIBCE
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Intel iC-86 Compiler v4.5
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Intel iC-86 Compiler v4.5'
+printf 'main(){return 0;}\n' > HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. C:\IC86.EXE HELLO.C small optimize\(3\) mod86 diagnostic\(2\) define\(INTELC\)
+/home/xor/kvikdos/kvikdos --mount=C:. C:\LINK86.EXE libs\cstdoss.obj,HELLO.obj,c:\libs\cdoss.lib,u\cel87.lib,u\e8087.lib,u\de8087,libs\clib87.lib TO HELLO.EXE exe
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Borland Turbo C 2.0
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Borland Turbo C v2'
+printf 'main(){return 0;}\n' > HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. C:\TCC.EXE -ms -Z -O -G -Iinclude -Llib -eHELLO.EXE HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Borland Turbo C++ 1.01
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Borland Turbo C++ v1'
+printf 'main(){return 0;}\n' > HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. --env=LIB=C:\LIB --env=INCLUDE=C:\INCLUDE C:\BIN\TCC.EXE -ms -Z -O -G -IC:\INCLUDE -LC:\LIB -eHELLO.EXE HELLO.C
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Microsoft MASM 5.0
+
+`MASM.EXE` works directly; `LINK.EXE` is easiest via stdin prompts.
+
+```bash
+cd '/home/xor/inertia_player/dos_compilers/Microsoft MASM v5/BIN'
+cat > HELLO.ASM <<'EOA'
+.MODEL SMALL
+.STACK 100h
+.CODE
+start:
+  mov ax,4C00h
+  int 21h
+END start
+EOA
+/home/xor/kvikdos/kvikdos --mount=C:. C:\MASM.EXE HELLO.ASM,HELLO.OBJ,NUL,NUL
+printf 'HELLO.OBJ\nHELLO.EXE\nNUL\n\n\n' | /home/xor/kvikdos/kvikdos --mount=C:. C:\LINK.EXE
+/home/xor/kvikdos/kvikdos --mount=C:. C:\HELLO.EXE
+```
+
+## Notes
+
+- If compile succeeds but link cannot find CRT objects/libs, your `LIB` path is wrong for the mounted layout.
+- If includes are missing, adjust `INCLUDE` to match the mounted layout.
+- For old compilers, avoid modern signatures (`int main(void)`) and rely on K&R-style `main()` for compatibility.

alink/.clang-format

@@ -0,0 +1,12 @@
+BasedOnStyle: LLVM
+IndentWidth: 4
+TabWidth: 8
+UseTab: Always
+BreakBeforeBraces: Allman
+ColumnLimit: 100
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+PointerAlignment: Right
+SortIncludes: false
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLoopsOnASingleLine: false

alink/.clang-tidy

@@ -0,0 +1,4 @@
+Checks: '-*,clang-analyzer-core.uninitialized.*'
+WarningsAsErrors: '*'
+HeaderFilterRegex: '.*ALINK\.H'
+FormatStyle: file

alink/.editorconfig

@@ -0,0 +1,10 @@
+root = true
+
+[*.{C,H}]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+indent_style = tab
+indent_size = 8
+tab_width = 8
+trim_trailing_whitespace = true

alink/.github/workflows/ci.yml

@@ -0,0 +1,17 @@
+name: ci
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  linux:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install toolchain
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y build-essential clang clang-tidy clang-format clang-tools cppcheck valgrind
+      - name: Run CI checks
+        run: make ci

alink/.gitignore

@@ -0,0 +1,3 @@
+*.o
+alink
+alink.san

alink/AGENTS.md

@@ -0,0 +1,21 @@
+# Repository Notes
+
+## Build
+
+- `make` builds the Linux host binary `alink`
+- `make sanitizers` builds `alink.san` with AddressSanitizer and UBSan
+
+## Checks
+
+- `make format-check`
+- `make tidy`
+- `make cppcheck`
+- `make analyze`
+- `make valgrind`
+- `make ci`
+
+## Conventions
+
+- Source files use uppercase DOS-era filenames and must be compiled as C, not C++
+- Linux path handling must continue to accept both `/` and `\`
+- Compiler warnings are treated as errors in the maintained build targets