1 files changed, 374 insertions, 0 deletions

diff --git a/src/lib_ffi.c b/src/lib_ffi.c
new file mode 100644
index 00000000..70d4c4a3
--- /dev/null
+++ b/src/lib_ffi.c
@@ -0,0 +1,374 @@
+/*
+** FFI library.
+** Copyright (C) 2005-2010 Mike Pall. See Copyright Notice in luajit.h
+*/
+
+#define lib_ffi_c
+#define LUA_LIB
+
+#include "lua.h"
+#include "lauxlib.h"
+#include "lualib.h"
+
+#include "lj_obj.h"
+
+#if LJ_HASFFI
+
+#include "lj_gc.h"
+#include "lj_err.h"
+#include "lj_str.h"
+#include "lj_ctype.h"
+#include "lj_cparse.h"
+#include "lj_cdata.h"
+#include "lj_cconv.h"
+#include "lj_lib.h"
+
+/* -- C type checks ------------------------------------------------------- */
+
+/* Check first argument for a C type and returns its ID. */
+static CTypeID ffi_checkctype(lua_State *L, CTState *cts)
+{
+  TValue *o = L->base;
+  if (!(o < L->top)) {
+  err_argtype:
+    lj_err_argtype(L, 1, "C type");
+  }
+  if (tvisstr(o)) {  /* Parse an abstract C type declaration. */
+    GCstr *s = strV(o);
+    CPState cp;
+    int errcode;
+    cp.L = L;
+    cp.cts = cts;
+    cp.srcname = strdata(s);
+    cp.p = strdata(s);
+    cp.mode = CPARSE_MODE_ABSTRACT|CPARSE_MODE_NOIMPLICIT;
+    errcode = lj_cparse(&cp);
+    if (errcode) lj_err_throw(L, errcode);  /* Propagate errors. */
+    return cp.val.id;
+  } else {
+    GCcdata *cd;
+    if (!tviscdata(o)) goto err_argtype;
+    cd = cdataV(o);
+    return cd->typeid == CTID_CTYPEID ? *(CTypeID *)cdataptr(cd) : cd->typeid;
+  }
+}
+
+/* Check argument for C data and return it. */
+static GCcdata *ffi_checkcdata(lua_State *L, int narg)
+{
+  TValue *o = L->base + narg-1;
+  if (!(o < L->top && tviscdata(o)))
+    lj_err_argt(L, narg, LUA_TCDATA);
+  return cdataV(o);
+}
+
+/* Convert argument to C pointer. */
+static void *ffi_checkptr(lua_State *L, int narg, CTypeID id)
+{
+  CTState *cts = ctype_cts(L);
+  TValue *o = L->base + narg-1;
+  void *p;
+  if (o >= L->top)
+    lj_err_arg(L, narg, LJ_ERR_NOVAL);
+  lj_cconv_ct_tv(cts, ctype_get(cts, id), (uint8_t *)&p, o, 0);
+  return p;
+}
+
+/* -- C type metamethods -------------------------------------------------- */
+
+#define LJLIB_MODULE_ffi_meta
+
+LJLIB_CF(ffi_meta___index)
+{
+  CTState *cts = ctype_cts(L);
+  CTInfo qual = 0;
+  CType *ct;
+  uint8_t *p;
+  TValue *o = L->base;
+  if (!(o+1 < L->top && tviscdata(o)))  /* Also checks for presence of key. */
+    lj_err_argt(L, 1, LUA_TCDATA);
+  ct = lj_cdata_index(cts, cdataV(o), o+1, &p, &qual);
+  lj_cdata_get(cts, ct, L->top-1, p);
+  return 1;
+}
+
+LJLIB_CF(ffi_meta___newindex)
+{
+  CTState *cts = ctype_cts(L);
+  CTInfo qual = 0;
+  CType *ct;
+  uint8_t *p;
+  TValue *o = L->base;
+  if (!(o+2 < L->top && tviscdata(o)))  /* Also checks for key and value. */
+    lj_err_argt(L, 1, LUA_TCDATA);
+  ct = lj_cdata_index(cts, cdataV(o), o+1, &p, &qual);
+  lj_cdata_set(cts, ct, p, o+2, qual);
+  return 0;
+}
+
+/* Forward declaration. */
+static int lj_cf_ffi_new(lua_State *L);
+
+LJLIB_CF(ffi_meta___call)
+{
+  GCcdata *cd = ffi_checkcdata(L, 1);
+  if (cd->typeid == CTID_CTYPEID)
+    return lj_cf_ffi_new(L);
+  lj_err_caller(L, LJ_ERR_FFI_NYICALL);
+  return 0;  /* unreachable */
+}
+
+LJLIB_CF(ffi_meta___tostring)
+{
+  GCcdata *cd = ffi_checkcdata(L, 1);
+  const char *msg = "cdata<%s>: %p";
+  CTypeID id = cd->typeid;
+  if (id == CTID_CTYPEID) {
+    msg = "ctype<%s>";
+    id = *(CTypeID *)cdataptr(cd);
+  } else {
+    CType *ct = ctype_raw(ctype_cts(L), id);
+    if (ctype_iscomplex(ct->info)) {
+      setstrV(L, L->top-1, lj_ctype_repr_complex(L, cdataptr(cd), ct->size));
+      return 1;
+    } else if (ct->size == 8 && ctype_isinteger(ct->info)) {
+      setstrV(L, L->top-1, lj_ctype_repr_int64(L, *(uint64_t *)cdataptr(cd),
+                                               (ct->info & CTF_UNSIGNED)));
+      return 1;
+    }
+  }
+  lj_str_pushf(L, msg, strdata(lj_ctype_repr(L, id, NULL)), cdataptr(cd));
+  return 1;
+}
+
+#include "lj_libdef.h"
+
+/* -- FFI library functions ----------------------------------------------- */
+
+#define LJLIB_MODULE_ffi
+
+LJLIB_CF(ffi_cdef)
+{
+  GCstr *s = lj_lib_checkstr(L, 1);
+  CPState cp;
+  int errcode;
+  cp.L = L;
+  cp.cts = ctype_cts(L);
+  cp.srcname = strdata(s);
+  cp.p = strdata(s);
+  cp.mode = CPARSE_MODE_MULTI|CPARSE_MODE_DIRECT;
+  errcode = lj_cparse(&cp);
+  if (errcode) lj_err_throw(L, errcode);  /* Propagate errors. */
+  lj_gc_check(L);
+  return 0;
+}
+
+LJLIB_CF(ffi_new)
+{
+  CTState *cts = ctype_cts(L);
+  CTypeID id = ffi_checkctype(L, cts);
+  CTSize sz;
+  CTInfo info = lj_ctype_info(cts, id, &sz);
+  TValue *o = L->base+1;
+  GCcdata *cd;
+  if ((info & CTF_VLA)) {
+    o++;
+    sz = lj_ctype_vlsize(cts, ctype_raw(cts, id),
+                         (CTSize)lj_lib_checkint(L, 2));
+  }
+  if (sz == CTSIZE_INVALID)
+    lj_err_arg(L, 1, LJ_ERR_FFI_INVSIZE);
+  if (!(info & CTF_VLA) && ctype_align(info) <= CT_MEMALIGN)
+    cd = lj_cdata_new(cts, id, sz);
+  else
+    cd = lj_cdata_newv(cts, id, sz, ctype_align(info));
+  setcdataV(L, o-1, cd);  /* Anchor the uninitialized cdata. */
+  lj_cconv_ct_init(cts, ctype_raw(cts, id), sz, cdataptr(cd),
+                   o, (MSize)(L->top - o));  /* Initialize cdata. */
+  L->top = o;  /* Only return the cdata itself. */
+  lj_gc_check(L);
+  return 1;
+}
+
+LJLIB_CF(ffi_typeof)
+{
+  CTState *cts = ctype_cts(L);
+  CTypeID id = ffi_checkctype(L, cts);
+  GCcdata *cd = lj_cdata_new(cts, CTID_CTYPEID, 4);
+  *(CTypeID *)cdataptr(cd) = id;
+  setcdataV(L, L->top-1, cd);
+  return 1;
+}
+
+LJLIB_CF(ffi_sizeof)
+{
+  CTState *cts = ctype_cts(L);
+  CTypeID id = ffi_checkctype(L, cts);
+  CTSize sz;
+  if (LJ_UNLIKELY(tviscdata(L->base) && cdataisv(cdataV(L->base)))) {
+    sz = cdatavlen(cdataV(L->base));
+  } else {
+    CType *ct = lj_ctype_rawref(cts, id);
+    if (ctype_isvltype(ct->info))
+      sz = lj_ctype_vlsize(cts, ct, (CTSize)lj_lib_checkint(L, 2));
+    else
+      sz = ctype_hassize(ct->info) ? ct->size : CTSIZE_INVALID;
+    if (LJ_UNLIKELY(sz == CTSIZE_INVALID)) {
+      setnilV(L->top-1);
+      return 1;
+    }
+  }
+  setintV(L->top-1, (int32_t)sz);
+  return 1;
+}
+
+LJLIB_CF(ffi_alignof)
+{
+  CTState *cts = ctype_cts(L);
+  CTypeID id = ffi_checkctype(L, cts);
+  CTSize sz = 0;
+  CTInfo info = lj_ctype_info(cts, id, &sz);
+  setintV(L->top-1, 1 << ctype_align(info));
+  return 1;
+}
+
+LJLIB_CF(ffi_offsetof)
+{
+  CTState *cts = ctype_cts(L);
+  CTypeID id = ffi_checkctype(L, cts);
+  GCstr *name = lj_lib_checkstr(L, 2);
+  CType *ct = lj_ctype_rawref(cts, id);
+  CTSize ofs;
+  if (ctype_isstruct(ct->info) && ct->size != CTSIZE_INVALID) {
+    CType *fct = lj_ctype_getfield(cts, ct, name, &ofs);
+    if (fct) {
+      setintV(L->top-1, ofs);
+      if (ctype_isfield(fct->info)) {
+        return 1;
+      } else if (ctype_isbitfield(fct->info)) {
+        setintV(L->top++, ctype_bitpos(fct->info));
+        setintV(L->top++, ctype_bitbsz(fct->info));
+        return 3;
+      }
+    }
+  }
+  return 0;
+}
+
+LJLIB_CF(ffi_cast)
+{
+  CTState *cts = ctype_cts(L);
+  CTypeID id = ffi_checkctype(L, cts);
+  TValue *o = lj_lib_checkany(L, 2);
+  L->top = o+1;  /* Make sure this is the last item on the stack. */
+  if (!(tviscdata(o) && cdataV(o)->typeid == id)) {
+    CTSize sz = lj_ctype_size(cts, id);
+    GCcdata *cd;
+    if (sz == CTSIZE_INVALID)
+      lj_err_caller(L, LJ_ERR_FFI_INVSIZE);
+    cd = lj_cdata_new(cts, id, sz);  /* Create destination cdata. */
+    lj_cconv_ct_tv(cts, ctype_raw(cts, id), cdataptr(cd), o, CCF_CAST);
+    setcdataV(L, o, cd);
+    lj_gc_check(L);
+  }
+  return 1;
+}
+
+LJLIB_CF(ffi_string)
+{
+  CTState *cts = ctype_cts(L);
+  TValue *o = lj_lib_checkany(L, 1);
+  size_t sz = (size_t)(CTSize)lj_lib_optint(L, 2, (int32_t)CTSIZE_INVALID);
+  CType *ct = ctype_get(cts, sz==CTSIZE_INVALID ? CTID_P_CVOID : CTID_P_CCHAR);
+  const char *p;
+  L->top = o+1;  /* Make sure this is the last item on the stack. */
+  lj_cconv_ct_tv(cts, ct, (uint8_t *)&p, o, 0);
+  if (sz == CTSIZE_INVALID) sz = strlen(p);
+  setstrV(L, o, lj_str_new(L, p, sz));
+  lj_gc_check(L);
+  return 1;
+}
+
+LJLIB_CF(ffi_copy)
+{
+  void *dp = ffi_checkptr(L, 1, CTID_P_VOID);
+  void *sp = ffi_checkptr(L, 2, CTID_P_CVOID);
+  TValue *o = L->base+1;
+  CTSize sz;
+  if (tvisstr(o) && o+1 >= L->top) {
+    sz = strV(o)->len+1;  /* Copy Lua string including trailing '\0'. */
+  } else {
+    sz = (CTSize)lj_lib_checkint(L, 3);
+    if (tvisstr(o) && sz > strV(o)->len+1)
+      sz = strV(o)->len+1;  /* Max. copy length is string length. */
+  }
+  memcpy(dp, sp, sz);
+  return 0;
+}
+
+LJLIB_CF(ffi_fill)
+{
+  void *dp = ffi_checkptr(L, 1, CTID_P_VOID);
+  CTSize sz = (CTSize)lj_lib_checkint(L, 2);
+  int32_t fill = lj_lib_optint(L, 3, 0);
+  memset(dp, fill, sz);
+  return 0;
+}
+
+#define H_(le, be)      LJ_ENDIAN_SELECT(0x##le, 0x##be)
+
+/* Test ABI string. */
+LJLIB_CF(ffi_abi)
+{
+  GCstr *s = lj_lib_checkstr(L, 1);
+  int b = 0;
+  switch (s->hash) {
+#if LJ_64
+  case H_(849858eb,ad35fd06): b = 1; break;  /* 64bit */
+#else
+  case H_(662d3c79,d0e22477): b = 1; break;  /* 32bit */
+#endif
+#if LJ_ARCH_HASFPU
+  case H_(e33ee463,e33ee463): b = 1; break;  /* fpu */
+#endif
+#if LJ_ABI_SOFTFP
+  case H_(61211a23,c2e8c81c): b = 1; break;  /* softfp */
+#else
+  case H_(539417a8,8ce0812f): b = 1; break;  /* hardfp */
+#endif
+#if LJ_ABI_EABI
+  case H_(2182df8f,f2ed1152): b = 1; break;  /* eabi */
+#endif
+#if LJ_ABI_WIN
+  case H_(4ab624a8,4ab624a8): b = 1; break;  /* win */
+#endif
+  case H_(3af93066,1f001464): b = 1; break;  /* le/be */
+  default:
+    break;
+  }
+  setboolV(L->top-1, b);
+  return 1;
+}
+
+#undef H_
+
+LJLIB_PUSH(top-3) LJLIB_SET(os)
+LJLIB_PUSH(top-2) LJLIB_SET(arch)
+
+#include "lj_libdef.h"
+
+/* ------------------------------------------------------------------------ */
+
+LUALIB_API int luaopen_ffi(lua_State *L)
+{
+  lj_ctype_init(L);
+  LJ_LIB_REG_(L, NULL, ffi_meta);
+  /* NOBARRIER: basemt is a GC root. */
+  setgcref(basemt_it(G(L), LJ_TCDATA), obj2gco(tabV(L->top-1)));
+  lua_pushliteral(L, LJ_OS_NAME);
+  lua_pushliteral(L, LJ_ARCH_NAME);
+  LJ_LIB_REG_(L, NULL, ffi);  /* Note: no global "ffi" created! */
+  return 1;
+}
+
+#endif