Development - #446
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…rce() calls in malloc - Add __clib4_resource field to struct _clib4 for caching the global resource pointer - Initialize cache once in stdlib_memory_init instead of calling OpenResource() on every allocation - Update __get_wmem_allocator, __memory_lock, and __memory_unlock to use cached pointer - Eliminates 3 OpenResource() calls per malloc/free (hot path optimization) - Maintains global allocator semantics and thread-safety through shared resource semaphore
dlopen(NULL):
- Previously returned NULL/ENOENT; POSIX requires it to return a
handle for the main program (entire application search scope).
- Now opens SOBJS:libc.so or PROGDIR:SObjs/libc.so so that the
returned handle is a real DSO handle on which DLSym() can find
LOCAL-scope symbols (malloc, getcwd, etc.) directly.
- Falls back to __dl_root_handle as a sentinel when no libc path
is available; dlsym/dlclose recognise and handle the sentinel.
dlsym / symbol resolution (xpcshell/powerfox regression):
- When a process already linked with clib4 calls dlopen("libc.so"),
the OS4 ELF loader returns a valid handle but DLSym() on it
returns ELF32_SYMBOL_NOT_FOUND because the symbols are already
present in the global ELF scope (provided by clib4.library).
- Added a fallback: if DLSym fails with ELF32_SYMBOL_NOT_FOUND on
a specific handle, retry with ELF32_RTLD_DEFAULT (global scope).
This mirrors the GNU ld.so behaviour for pre-loaded libraries.
dlclose(NULL-sentinel):
- dlclose() on the __dl_root_handle sentinel is now a documented
no-op (closing the main program handle must not crash).
Adds test_programs/dlopen/dlsym_test.c to exercise all cases.
Root cause of the xpcshell/powerfox DSI crash at exit:
1. InitSHLibs(hSelf, TRUE) loads libc.so (refcount=1) and registers
its destructors in the process __EXT_DTOR_LIST__.
2. JS ctypes opens libc.so via dlopen() -> refcount=2.
3. XPCOM/ctypes shutdown calls dlclose() on all opened handles.
If the refcount reaches 0, the ELF loader unmaps libc.so.
4. call_main() then runs _end_ctors(__EXT_DTOR_LIST__), which calls
function pointers into the now-unmapped libc.so -> DSI crash
(r30 = invalid TOC base, lwz from freed memory).
Fix: open a permanent 'anchor' handle on libc.so at the start of
call_main() and release it after _end_ctors() has finished, before
shared_obj_init(FALSE). This guarantees the ELF reference count
never drops to zero while any destructor might still reference
libc.so code or data.
The anchor is opened in call_main() rather than reent_init() to
avoid a re-entrant libOpen() loop: at call_main() time clib4 is
fully initialised (__fully_initialized == TRUE, pr_UID set), so
a re-entrant libOpen() triggered by loading libc.so takes the
early-return path safely. Opening the anchor during reent_init()
would cause libc.so to call OpenLibrary(clib4) -> libOpen ->
reent_init -> DLOpen(libc.so) -> infinite loop.
As a side effect this also keeps libc.so symbols resolvable via
dlsym() throughout the entire process lifetime, which fixed the
powerfox OS.File ctypes symbol resolution failures.
Changes:
- dos.h: add void *__dl_libc_anchor to struct _clib4 (at end,
ABI-compatible)
- libc_init_global.c (reent_init): only set __dl_root_handle;
no DLOpen here to avoid the init loop.
- libc_init_global.c (reent_exit): DLClose anchor as safety net
(will already be NULL if call_main ran normally).
- stdlib/main.c (call_main): open anchor before shared_obj_init(TRUE),
close it after _end_ctors() and before shared_obj_init(FALSE).
SOBJS:libc.so belongs to newlib, not clib4. Use PROGDIR:libc.so as the fallback path for the libc anchor and dlopen(NULL) self-handle lookup.
Conflict in library/dos.h resolved: keep __dl_libc_anchor (added by the fix branch) after __clib4_resource (added by the malloc optimization branch). Both fields are at the end of struct _clib4, preserving ABI compatibility.
* fix: memory leaks in cleanup paths - unistd/init_exit.c: free UnlinkNode structs after RemHead in unistd_exit - stdlib/arg.c: save command_line to __command_line_ptr (assignment was missing); save nti_argv0 in __clib4->unused2, free in arg_exit (was orphaned) - stdlib/atexit.c: free dynamically-allocated ExitTrapNode entries (>32) in __exit_trap_trigger after invoking each handler - locale/dcngettext.c: munmap mofile->map before free(mofile) in dcngettext_exit; null out g_mofile after freeing - unistd/wildcard_expand.c: free quote_vector static buffer in __wildcard_expand_exit - dos.h: document usage of unused2 field - posix/mmap_internal.h, mmap.c, munmap.c: mmap cleanup improvements * Added mmap_internal.h to main.c to fix compilation error Added 2 new threads tests * DON'T USE SOBJS:libc.so when using __dl_root_handle! * Removed DOS obsolete flags and removed <dos/obsolete.h> include file
Fixes for the pipelines
Add malloc_usable_size() using the existing wmem allocator metadata: - wmem: add wsize() function pointer to _wmem_allocator_t vtable - wmem: implement wmem_block_size() in O(1) via wmem_block_pre_t/chunk->len - wmem: implement wmem_block_fast_size() in O(1) via chunk->size - wmem: implement wmem_simple_size() via sizes[] array scan - wmem: implement wmem_strict_size() via blocks list scan - wmem: expose wmem_alloc_size() public API in wmem_core.c/h - stdlib: add malloc_usable_size.c with malloc_usable_size() / __malloc_usable_size_r() - include: declare malloc_usable_size() in malloc.h - test: add test_programs/memory/malloc_usable_size.c
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