--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/luajit/src/lj_clib.c	Thu Jan 22 20:10:30 2026 -0800
@@ -0,0 +1,434 @@
+/*
+** FFI C library loader.
+** Copyright (C) 2005-2023 Mike Pall. See Copyright Notice in luajit.h
+*/
+
+#include "lj_obj.h"
+
+#if LJ_HASFFI
+
+#include "lj_gc.h"
+#include "lj_err.h"
+#include "lj_tab.h"
+#include "lj_str.h"
+#include "lj_udata.h"
+#include "lj_ctype.h"
+#include "lj_cconv.h"
+#include "lj_cdata.h"
+#include "lj_clib.h"
+#include "lj_strfmt.h"
+
+/* -- OS-specific functions ----------------------------------------------- */
+
+#if LJ_TARGET_DLOPEN
+
+#include <dlfcn.h>
+#include <stdio.h>
+
+#if defined(RTLD_DEFAULT) && !defined(NO_RTLD_DEFAULT)
+#define CLIB_DEFHANDLE	RTLD_DEFAULT
+#elif LJ_TARGET_OSX || LJ_TARGET_BSD
+#define CLIB_DEFHANDLE	((void *)(intptr_t)-2)
+#else
+#define CLIB_DEFHANDLE	NULL
+#endif
+
+LJ_NORET LJ_NOINLINE static void clib_error_(lua_State *L)
+{
+  lj_err_callermsg(L, dlerror());
+}
+
+#define clib_error(L, fmt, name)	clib_error_(L)
+
+#if LJ_TARGET_CYGWIN
+#define CLIB_SOPREFIX	"cyg"
+#else
+#define CLIB_SOPREFIX	"lib"
+#endif
+
+#if LJ_TARGET_OSX
+#define CLIB_SOEXT	"%s.dylib"
+#elif LJ_TARGET_CYGWIN
+#define CLIB_SOEXT	"%s.dll"
+#else
+#define CLIB_SOEXT	"%s.so"
+#endif
+
+static const char *clib_extname(lua_State *L, const char *name)
+{
+  if (!strchr(name, '/')
+#if LJ_TARGET_CYGWIN
+      && !strchr(name, '\\')
+#endif
+     ) {
+    if (!strchr(name, '.')) {
+      name = lj_strfmt_pushf(L, CLIB_SOEXT, name);
+      L->top--;
+#if LJ_TARGET_CYGWIN
+    } else {
+      return name;
+#endif
+    }
+    if (!(name[0] == CLIB_SOPREFIX[0] && name[1] == CLIB_SOPREFIX[1] &&
+	  name[2] == CLIB_SOPREFIX[2])) {
+      name = lj_strfmt_pushf(L, CLIB_SOPREFIX "%s", name);
+      L->top--;
+    }
+  }
+  return name;
+}
+
+/* Check for a recognized ld script line. */
+static const char *clib_check_lds(lua_State *L, const char *buf)
+{
+  char *p, *e;
+  if ((!strncmp(buf, "GROUP", 5) || !strncmp(buf, "INPUT", 5)) &&
+      (p = strchr(buf, '('))) {
+    while (*++p == ' ') ;
+    for (e = p; *e && *e != ' ' && *e != ')'; e++) ;
+    return strdata(lj_str_new(L, p, e-p));
+  }
+  return NULL;
+}
+
+/* Quick and dirty solution to resolve shared library name from ld script. */
+static const char *clib_resolve_lds(lua_State *L, const char *name)
+{
+  FILE *fp = fopen(name, "r");
+  const char *p = NULL;
+  if (fp) {
+    char buf[256];
+    if (fgets(buf, sizeof(buf), fp)) {
+      if (!strncmp(buf, "/* GNU ld script", 16)) {  /* ld script magic? */
+	while (fgets(buf, sizeof(buf), fp)) {  /* Check all lines. */
+	  p = clib_check_lds(L, buf);
+	  if (p) break;
+	}
+      } else {  /* Otherwise check only the first line. */
+	p = clib_check_lds(L, buf);
+      }
+    }
+    fclose(fp);
+  }
+  return p;
+}
+
+static void *clib_loadlib(lua_State *L, const char *name, int global)
+{
+  void *h = dlopen(clib_extname(L, name),
+		   RTLD_LAZY | (global?RTLD_GLOBAL:RTLD_LOCAL));
+  if (!h) {
+    const char *e, *err = dlerror();
+    if (err && *err == '/' && (e = strchr(err, ':')) &&
+	(name = clib_resolve_lds(L, strdata(lj_str_new(L, err, e-err))))) {
+      h = dlopen(name, RTLD_LAZY | (global?RTLD_GLOBAL:RTLD_LOCAL));
+      if (h) return h;
+      err = dlerror();
+    }
+    if (!err) err = "dlopen failed";
+    lj_err_callermsg(L, err);
+  }
+  return h;
+}
+
+static void clib_unloadlib(CLibrary *cl)
+{
+  if (cl->handle && cl->handle != CLIB_DEFHANDLE)
+    dlclose(cl->handle);
+}
+
+static void *clib_getsym(CLibrary *cl, const char *name)
+{
+  void *p = dlsym(cl->handle, name);
+  return p;
+}
+
+#elif LJ_TARGET_WINDOWS
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+#ifndef GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
+#define GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS	4
+#define GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT	2
+BOOL WINAPI GetModuleHandleExA(DWORD, LPCSTR, HMODULE*);
+#endif
+
+#define CLIB_DEFHANDLE	((void *)-1)
+
+/* Default libraries. */
+enum {
+  CLIB_HANDLE_EXE,
+#if !LJ_TARGET_UWP
+  CLIB_HANDLE_DLL,
+  CLIB_HANDLE_CRT,
+  CLIB_HANDLE_KERNEL32,
+  CLIB_HANDLE_USER32,
+  CLIB_HANDLE_GDI32,
+#endif
+  CLIB_HANDLE_MAX
+};
+
+static void *clib_def_handle[CLIB_HANDLE_MAX];
+
+LJ_NORET LJ_NOINLINE static void clib_error(lua_State *L, const char *fmt,
+					    const char *name)
+{
+  DWORD err = GetLastError();
+#if LJ_TARGET_XBOXONE
+  wchar_t wbuf[128];
+  char buf[128*2];
+  if (!FormatMessageW(FORMAT_MESSAGE_IGNORE_INSERTS|FORMAT_MESSAGE_FROM_SYSTEM,
+		      NULL, err, 0, wbuf, sizeof(wbuf)/sizeof(wchar_t), NULL) ||
+      !WideCharToMultiByte(CP_ACP, 0, wbuf, 128, buf, 128*2, NULL, NULL))
+#else
+  char buf[128];
+  if (!FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS|FORMAT_MESSAGE_FROM_SYSTEM,
+		      NULL, err, 0, buf, sizeof(buf), NULL))
+#endif
+    buf[0] = '\0';
+  lj_err_callermsg(L, lj_strfmt_pushf(L, fmt, name, buf));
+}
+
+static int clib_needext(const char *s)
+{
+  while (*s) {
+    if (*s == '/' || *s == '\\' || *s == '.') return 0;
+    s++;
+  }
+  return 1;
+}
+
+static const char *clib_extname(lua_State *L, const char *name)
+{
+  if (clib_needext(name)) {
+    name = lj_strfmt_pushf(L, "%s.dll", name);
+    L->top--;
+  }
+  return name;
+}
+
+static void *clib_loadlib(lua_State *L, const char *name, int global)
+{
+  DWORD oldwerr = GetLastError();
+  void *h = LJ_WIN_LOADLIBA(clib_extname(L, name));
+  if (!h) clib_error(L, "cannot load module " LUA_QS ": %s", name);
+  SetLastError(oldwerr);
+  UNUSED(global);
+  return h;
+}
+
+static void clib_unloadlib(CLibrary *cl)
+{
+  if (cl->handle == CLIB_DEFHANDLE) {
+#if !LJ_TARGET_UWP
+    MSize i;
+    for (i = CLIB_HANDLE_KERNEL32; i < CLIB_HANDLE_MAX; i++) {
+      void *h = clib_def_handle[i];
+      if (h) {
+	clib_def_handle[i] = NULL;
+	FreeLibrary((HINSTANCE)h);
+      }
+    }
+#endif
+  } else if (cl->handle) {
+    FreeLibrary((HINSTANCE)cl->handle);
+  }
+}
+
+#if LJ_TARGET_UWP
+EXTERN_C IMAGE_DOS_HEADER __ImageBase;
+#endif
+
+static void *clib_getsym(CLibrary *cl, const char *name)
+{
+  void *p = NULL;
+  if (cl->handle == CLIB_DEFHANDLE) {  /* Search default libraries. */
+    MSize i;
+    for (i = 0; i < CLIB_HANDLE_MAX; i++) {
+      HINSTANCE h = (HINSTANCE)clib_def_handle[i];
+      if (!(void *)h) {  /* Resolve default library handles (once). */
+#if LJ_TARGET_UWP
+	h = (HINSTANCE)&__ImageBase;
+#else
+	switch (i) {
+	case CLIB_HANDLE_EXE: GetModuleHandleExA(GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, NULL, &h); break;
+	case CLIB_HANDLE_DLL:
+	  GetModuleHandleExA(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS|GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
+			     (const char *)clib_def_handle, &h);
+	  break;
+	case CLIB_HANDLE_CRT:
+	  GetModuleHandleExA(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS|GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
+			     (const char *)&_fmode, &h);
+	  break;
+	case CLIB_HANDLE_KERNEL32: h = LJ_WIN_LOADLIBA("kernel32.dll"); break;
+	case CLIB_HANDLE_USER32: h = LJ_WIN_LOADLIBA("user32.dll"); break;
+	case CLIB_HANDLE_GDI32: h = LJ_WIN_LOADLIBA("gdi32.dll"); break;
+	}
+	if (!h) continue;
+#endif
+	clib_def_handle[i] = (void *)h;
+      }
+      p = (void *)GetProcAddress(h, name);
+      if (p) break;
+    }
+  } else {
+    p = (void *)GetProcAddress((HINSTANCE)cl->handle, name);
+  }
+  return p;
+}
+
+#else
+
+#define CLIB_DEFHANDLE	NULL
+
+LJ_NORET LJ_NOINLINE static void clib_error(lua_State *L, const char *fmt,
+					    const char *name)
+{
+  lj_err_callermsg(L, lj_strfmt_pushf(L, fmt, name, "no support for this OS"));
+}
+
+static void *clib_loadlib(lua_State *L, const char *name, int global)
+{
+  lj_err_callermsg(L, "no support for loading dynamic libraries for this OS");
+  UNUSED(name); UNUSED(global);
+  return NULL;
+}
+
+static void clib_unloadlib(CLibrary *cl)
+{
+  UNUSED(cl);
+}
+
+static void *clib_getsym(CLibrary *cl, const char *name)
+{
+  UNUSED(cl); UNUSED(name);
+  return NULL;
+}
+
+#endif
+
+/* -- C library indexing -------------------------------------------------- */
+
+#if LJ_TARGET_X86 && LJ_ABI_WIN
+/* Compute argument size for fastcall/stdcall functions. */
+static CTSize clib_func_argsize(CTState *cts, CType *ct)
+{
+  CTSize n = 0;
+  while (ct->sib) {
+    CType *d;
+    ct = ctype_get(cts, ct->sib);
+    if (ctype_isfield(ct->info)) {
+      d = ctype_rawchild(cts, ct);
+      n += ((d->size + 3) & ~3);
+    }
+  }
+  return n;
+}
+#endif
+
+/* Get redirected or mangled external symbol. */
+static const char *clib_extsym(CTState *cts, CType *ct, GCstr *name)
+{
+  if (ct->sib) {
+    CType *ctf = ctype_get(cts, ct->sib);
+    if (ctype_isxattrib(ctf->info, CTA_REDIR))
+      return strdata(gco2str(gcref(ctf->name)));
+  }
+  return strdata(name);
+}
+
+/* Index a C library by name. */
+TValue *lj_clib_index(lua_State *L, CLibrary *cl, GCstr *name)
+{
+  TValue *tv = lj_tab_setstr(L, cl->cache, name);
+  if (LJ_UNLIKELY(tvisnil(tv))) {
+    CTState *cts = ctype_cts(L);
+    CType *ct;
+    CTypeID id = lj_ctype_getname(cts, &ct, name, CLNS_INDEX);
+    if (!id)
+      lj_err_callerv(L, LJ_ERR_FFI_NODECL, strdata(name));
+    if (ctype_isconstval(ct->info)) {
+      CType *ctt = ctype_child(cts, ct);
+      lj_assertCTS(ctype_isinteger(ctt->info) && ctt->size <= 4,
+		   "only 32 bit const supported");  /* NYI */
+      if ((ctt->info & CTF_UNSIGNED) && (int32_t)ct->size < 0)
+	setnumV(tv, (lua_Number)(uint32_t)ct->size);
+      else
+	setintV(tv, (int32_t)ct->size);
+    } else {
+      const char *sym = clib_extsym(cts, ct, name);
+#if LJ_TARGET_WINDOWS
+      DWORD oldwerr = GetLastError();
+#endif
+      void *p = clib_getsym(cl, sym);
+      GCcdata *cd;
+      lj_assertCTS(ctype_isfunc(ct->info) || ctype_isextern(ct->info),
+		   "unexpected ctype %08x in clib", ct->info);
+#if LJ_TARGET_X86 && LJ_ABI_WIN
+      /* Retry with decorated name for fastcall/stdcall functions. */
+      if (!p && ctype_isfunc(ct->info)) {
+	CTInfo cconv = ctype_cconv(ct->info);
+	if (cconv == CTCC_FASTCALL || cconv == CTCC_STDCALL) {
+	  CTSize sz = clib_func_argsize(cts, ct);
+	  const char *symd = lj_strfmt_pushf(L,
+			       cconv == CTCC_FASTCALL ? "@%s@%d" : "_%s@%d",
+			       sym, sz);
+	  L->top--;
+	  p = clib_getsym(cl, symd);
+	}
+      }
+#endif
+      if (!p)
+	clib_error(L, "cannot resolve symbol " LUA_QS ": %s", sym);
+#if LJ_TARGET_WINDOWS
+      SetLastError(oldwerr);
+#endif
+      cd = lj_cdata_new(cts, id, CTSIZE_PTR);
+      *(void **)cdataptr(cd) = p;
+      setcdataV(L, tv, cd);
+      lj_gc_anybarriert(L, cl->cache);
+    }
+  }
+  return tv;
+}
+
+/* -- C library management ------------------------------------------------ */
+
+/* Create a new CLibrary object and push it on the stack. */
+static CLibrary *clib_new(lua_State *L, GCtab *mt)
+{
+  GCtab *t = lj_tab_new(L, 0, 0);
+  GCudata *ud = lj_udata_new(L, sizeof(CLibrary), t);
+  CLibrary *cl = (CLibrary *)uddata(ud);
+  cl->cache = t;
+  ud->udtype = UDTYPE_FFI_CLIB;
+  /* NOBARRIER: The GCudata is new (marked white). */
+  setgcref(ud->metatable, obj2gco(mt));
+  setudataV(L, L->top++, ud);
+  return cl;
+}
+
+/* Load a C library. */
+void lj_clib_load(lua_State *L, GCtab *mt, GCstr *name, int global)
+{
+  void *handle = clib_loadlib(L, strdata(name), global);
+  CLibrary *cl = clib_new(L, mt);
+  cl->handle = handle;
+}
+
+/* Unload a C library. */
+void lj_clib_unload(CLibrary *cl)
+{
+  clib_unloadlib(cl);
+  cl->handle = NULL;
+}
+
+/* Create the default C library object. */
+void lj_clib_default(lua_State *L, GCtab *mt)
+{
+  CLibrary *cl = clib_new(L, mt);
+  cl->handle = CLIB_DEFHANDLE;
+}
+
+#endif