When spamming file changes rapidly, inotify can report stale UNLOAD/RELOAD
events for modules that were already unloaded by previous events in the same
poll cycle. This caused is_mod_loaded() to return -1, which was then cast to
size_t (18446744073709551615) and used as an array index, causing segfaults.
Additionally, event counts were calculated before validation, causing loops to
run more iterations than valid indices were populated, reading garbage values.
Changes:
- stk.c: Check if is_mod_loaded() returns valid index (>= 0) before adding
to unload/reload lists
- stk.c: Reset and recalculate counts after populating arrays with only valid
indices to prevent loop overrun
- Skip processing events for modules that are no longer loaded
This completes the Linux stability fixes started in v0.0.2.
Fixes multiple issues causing segfaults when hot-reloading modules
on Linux, particularly when file changes are detected rapidly:
- Enable is_file_ready() check on Linux to prevent loading partially-written
shared libraries (previously only used on Windows/BSD)
- Fix event deduplication on Linux to actually remove duplicate inotify events
instead of just marking them, preventing double-free on same module
- Reorder reload operations to unload old module only after successfully
copying new version, avoiding invalid state when copy fails
Changes:
- platform.c: Remove __linux__ guards around is_file_ready() function
- platform.c: Add compaction step after deduplication to remove -1 entries
- stk.c: Move module unload to after platform_copy_file() in reload loop
These changes make Linux hot-reload as robust as Windows/BSD implementations.
- Install headers to /include/stk/ instead of /include/
- Update README examples to use #include <stk/stk.h>
- Update Windows install instructions to reflect stk/ directory structure
- Add MPL-2.0 license badge to README
- Clarify DLL can be placed in binary or lib directory on Windows
This prevents header name collisions with other libraries and follows
standard library distribution conventions (similar to SDL).
Users now include stk headers as <stk/stk.h> rather than <stk.h>.
- Add PREFIX, LIBDIR, and INCDIR variables (default: /usr/local)
- Implement install target that builds release and installs to system paths
- Implement uninstall target to cleanly remove installed files
- Support custom install locations via PREFIX variable
- Add helpful message on Windows directing users to manual installation
Both gmake.mk and bmake.mk now support standard installation workflow
on Unix-like systems (Linux, BSD, macOS). Windows users are instructed
to copy files manually as per platform conventions.
Usage:
make install # Install to /usr/local (requires root)
make PREFIX=$HOME install # Install to custom location
make uninstall # Remove installed files
- Replace undefined 'len' variable references with 'name_len'
- Add explicit null terminators after memcpy operations
- Move name_len declaration to Windows-specific scope to eliminate unused variable warning on BSD
- Standardize string copy pattern across all platforms: strlen -> clamp -> memcpy -> null terminate
- Fix increment operator placement for clarity (i++ moved outside array indexing)
- Remove duplicate name_len declaration in platform_directory_watch_check
This ensures proper bounds checking and null termination for filenames
on both Windows and BSD systems, preventing potential buffer overflows
when handling long filenames (approaching STK_PATH_MAX).
- Add OS detection for Windows vs Unix platforms
- Handle .exe extension on Windows for test program
- Fix directory creation with Windows-native commands (mkdir/copy vs mkdir -p/cp)
- Update clean target to use appropriate commands per platform
- Set PATH environment for DLL loading on Windows
- Remove broken uname detection that fails on Windows
Prevent potential format string mismatches on platforms where
size_t and unsigned long may have different sizes by explicitly
casting size_t variables to unsigned long when using %lu format
specifier in printf calls.
- Use absolute path ${.CURDIR}/test in main bmake.mk
- Replace automatic variable $< with explicit source filenames in test/bmake.mk
- Ensure proper directory navigation and source file compilation
- Fixes "undefined symbol: main" linker error on BSD systems
- Add test target to both bmake.mk and gmake.mk Makefiles
- Add test-related artifacts to .gitignore (excluding DLLs/shared libs)
- Create test directory with cross-platform Makefiles (bmake.mk, gmake.mk)
- Implement cross-platform test program with signal handling (test.c)
- Add test module source for compilation (test_mod.c)
- Set up automated test environment with mods/ directory
- Support both POSIX and Windows platforms
The test infrastructure allows running integration tests via 'make test'
and demonstrates stk library functionality with dynamic module loading.
Generated DLLs/shared libraries are excluded from version control.
- In stk_module_load: Use memcpy with explicit length check instead of strncpy
- In platform_directory_init_scan: Same fix for directory scanning
- In stk_module_realloc_memory: Replace realloc with malloc+memcpy approach
to avoid potential use-after-free issues and compiler warnings
- All changes maintain same functionality with improved safety
- Update module load and memory functions to use fixed-width uint8_t
- Implement STK_MOD_REALLOC_FAILURE for granular memory error tracking
- Clean up logging prefixes in stk_poll for consistency
- Update error string helper to support new module error codes
On Windows, module IDs were failing to load because paths were being
constructed with hardcoded forward slashes. Oops...
- Added platform.h to centralize path separator macros.
- Updated build_path in stk.c to use STK_PATH_SEP_STR instead of "/".
- Cleaned up redundant platform logic in module.c.
Add platform-specific protections against race conditions when
module files are written rapidly (compilation, copying, etc).
Linux (inotify):
- Deduplicate events within a poll cycle to prevent double-unload
- When duplicate RELOAD events occur, earlier events are skipped
and only the final event is processed
BSD (kqueue):
- Add file readiness check with flock() before processing mtime changes
- Files that aren't ready have their mtime reset, skipping the reload
All Unix platforms:
- Use atomic .tmp + rename for module copying to prevent loading
partially-written files
Writes that occur during an active reload or when files aren't
ready are skipped. A subsequent write is required to trigger
detection of those changes.
Fixes segfault caused by processing duplicate reload events
(Linux) or copying incomplete files mid-write (BSD).
Add strict error handling for stk initialization and platform operations.
stk_init() now fails fast on critical errors and returns typed error codes
that users can handle programmatically.
Changes:
- Add STK_INIT_* error codes for init failures (memory, tmpdir, watch)
- Add STK_PLATFORM_* error codes for platform operation results
- Check platform_mkdir() and fail if temp directory cannot be created
- Check platform_directory_watch_start() and fail if watch cannot initialize
- Add error_cleanup path in platform_directory_watch_start() to properly
free resources on critical Windows failures.
- Replace all platform error checks with STK_PLATFORM_OPERATION_SUCCESS
- Log FATAL errors with when critical operations fail
- Add warning logs for non-critical failures
Critical failures now return specific error codes:
- STK_INIT_MEMORY_ERROR: Module memory allocation failed
- STK_INIT_TMPDIR_ERROR: Cannot create temp directory
- STK_INIT_WATCH_ERROR: Cannot start directory watching
Individual module load failures remain non-fatal and are handled logged.
Modules that fail to load no longer crash or leak memory:
- Check return values from stk_module_load_init() and stk_module_load()
- Log errors with specific failure reasons (library load, symbol lookup, init)
- Track successful_loads counter separately from file_count
- Only increment module_count for modules that actually loaded
- Trim allocated arrays when some modules fail to load
- Continue loading other modules when one fails
This prevents crashes from accessing uninitialized module slots and
avoids memory leaks from over-allocation.
* Types: Corrected stk.c to use stk_init_mod_func and stk_shutdown_mod_func instead of generic types.
* Errors: Replaced -3 placeholder with STK_MOD_INIT_FAILURE.
* Cleanup: Moved typedefs in module.c for consistency.
* Define Constants: Added STK_MOD_LIBRARY_LOAD_ERROR and STK_MOD_SYMBOL_NOT_FOUND_ERROR to the public header.
* Update module.c: Swapped out the -1 and -2 placeholders for the new named constants in stk_module_load.
* Add STK_MOD_INIT_SUCCESS and STK_MOD_INIT_FAILURE macros to stk.h.
* Update stk_module_load to validate module initialization before finalizing the load.
* Unload library if the init func fails, return error.
* Define stk_init_mod_func as int (*)(void) and stk_shutdown_mod_func as void (*)(void).
* Update stk_inits and stk_shutdowns arrays to use the new specific function pointer types.
* Update the symbol lookup union in stk_module_load to support distinct init and shutdown signatures.
* Adjust memory allocation and reallocation logic in stk_module_init_memory and stk_module_realloc_memory to match new type sizes.
- Define STK_PATH_SEP macro to handle Windows and Unix path separators.
- Refactor extract_module_id to use STK_PATH_SEP.
- Simplify stk_module_load by delegating module ID extraction to extract_module_id.
* Resolve STATUS_INVALID_IMAGE_FORMAT on Windows by preventing race conditions during file I/O.
* is_file_ready: Uses GENERIC_WRITE to block if any process (compiler, copy, etc.) is writing to the source. Added GetFileSize check to ensure headers are flushed.
* platform_copy_file: Copies to .tmp and uses MoveFileExA for an atomic swap, hiding the file from the loader until completion.
* Refactor: Unified Win32 and POSIX logic with a single exit point.
Implement complete hot-reload logic in stk_poll() supporting reload,
load, and unload operations. Module arrays dynamically grow/shrink
with automatic defragmentation to maintain tight memory layout.
- Grow arrays when loads exceed unloads
- Fill holes left by unloads with new modules
- Defragment and trim arrays when unloads exceed loads
- Unload before realloc to minimize peak memory usage
- Replace sprintf with safe C89 build_path() helper
* Set all module slot fields (handle, init, shutdown, id) to NULL/empty
after unloading to prevent use-after-free and enable proper hole
detection during array defragmentation.
* Implement stk_module_realloc_memory() to grow or shrink module arrays during hot-reload operations.
* All-or-nothing strategy with fallback to original pointers on partial realloc failure.
Replace the placeholder TODO logs in the polling loop with logic to
resolve filesystem events into specific module indices.
- Centralizing State: Refactored is_module_loaded to is_mod_loaded to
check against the global stk_module_ids array, removing the need to
pass local buffers and preparing for unified lifetime management.
- Standardizing Identity: Updated extract_module_id to use a
consistent output buffer.
- Categorized Event Processing: Implemented a two-pass approach in
stk_poll to count event types (LOAD, UNLOAD, RELOAD) and allocate
tracking arrays, replacing the previous stubbed switch statement.
- Mapping Events to Indices: The poll loop now resolves filenames
back to their specific loaded indices via is_mod_loaded to
identify exactly which mod_id and index require action.
- Improved Flow Control: Introduced a finish_stk_poll label to
ensure consistent cleanup and return values when no events are
detected or processing is complete.
* Introduced stk_initialized flag.
* Updated all configuration setters (stk_set_mod_dir, stk_set_tmp_dir_name, stk_set_module_init_fn, and stk_set_module_shutdown_fn) to silently return if the library is already initialized.
* Ensures internal state consistency by locking paths and function entry points once stk_init has been called.
* Added functions to set mod dir, temp dir name, and module init/shutdown function names.
* Replaced hardcoded string literals with configurable static buffers in module.c.
* Improved string safety by replacing sprintf with strncpy/strncat.
* Updated stk_init local path buffers to handle maximum combined path lengths.
- Change %zu to %lu in stk_init to support older msvcrt.dll (Windows 7/XP)
- Update pluralization logic to correctly handle "0 mods" vs "1 mod"
- Add temporary stk_log calls to stk_poll for monitoring module events
Refactor memory allocation patterns:
- Replace realloc-in-loop with count-then-allocate pattern across all platforms
- Eliminate arbitrary buffer sizes (e.g., malloc(8 * ...)) in favor of exact counts
- Reduce allocation overhead by pre-counting items before malloc
Fix Windows file watching:
- Replace unreliable FindFirstChangeNotification with directory handle approach
- Add is_file_ready() to prevent events while compiler is still writing files
- Preserve timestamps when file is locked to retry on next poll
- Fix do-while loop in platform_directory_init_scan (was skipping first file)
Fix Linux inotify event handling:
- Consolidate DELETE+CREATE pairs into single RELOAD event
- Prevents duplicate events when compiler uses temp-file-and-rename pattern
Fix BSD/macOS kqueue implementation:
- Remove realloc loops from update_watches() and watch initialization
- Pre-count files before allocating file descriptor arrays
All platforms now correctly handle:
- Compiler overwrites (temp file operations)
- Manual copy/move operations
- Explicit file deletions
Tested on Linux, Windows 10, and FreeBSD.
Unlike inotify, Windows and BSD require manual state snapshots to detect
specific file changes. This refactor standardizes that manual handling
to ensure it is resource-safe and easy to follow.
- Fix memory leaks in platform_directory_watch_check where temporary
buffers (new_snaps, file_list) were not reliably freed on 'phantom'
triggers or error paths.
- Unify control flow using a 'goto' cleanup pattern to ensure
deterministic resource deallocation.
- Synchronizes the manual snapshot comparison logic between Windows
and BSD to ensure identical LOAD/RELOAD/UNLOAD event behavior.
- Simplifies the platform_directory_init_scan logic by removing
redundant directory rewinds and nested checks.
- Add WIN32_LEAN_AND_MEAN to optimize Windows header inclusion.
- Align internal API signatures (is_module_loaded) for consistency.
- Include <stdint.h> so Windows does not complain about int types.
- Cast GetProcAddress return through intptr_t to satisfy -Wpedantic.
- Moved work_path for *nix only macros.
anth64