string pointers are always fully aligned

ldebug.c

@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.c,v 1.60 2001/02/07 18:13:49 roberto Exp roberto $
+** $Id: ldebug.c,v 1.61 2001/02/09 18:37:33 roberto Exp roberto $
 ** Debug Interface
 ** See Copyright Notice in lua.h
 */
@@ -198,7 +198,7 @@ LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
 
 
 static void infoLproto (lua_Debug *ar, Proto *f) {
-  ar->source = f->source->str;
+  ar->source = getstr(f->source);
   ar->linedefined = f->lineDefined;
   ar->what = "Lua";
 }
@@ -249,7 +249,7 @@ static const char *travglobals (lua_State *L, const TObject *o) {
   for (i=0; i<g->size; i++) {
     if (luaO_equalObj(o, val(node(g, i))) &&
         ttype_key(node(g, i)) == LUA_TSTRING)
-      return tsvalue_key(node(g, i))->str;
+      return getstr(tsvalue_key(node(g, i)));
   }
   return NULL;
 }
@@ -499,7 +499,7 @@ static const char *getobjname (lua_State *L, StkId obj, const char **name) {
     lua_assert(pc != -1);
     switch (GET_OPCODE(i)) {
       case OP_GETGLOBAL: {
-        *name = p->kstr[GETARG_U(i)]->str;
+        *name = getstr(p->kstr[GETARG_U(i)]);
         return "global";
       }
       case OP_GETLOCAL: {
@@ -509,7 +509,7 @@ static const char *getobjname (lua_State *L, StkId obj, const char **name) {
       }
       case OP_PUSHSELF:
       case OP_GETDOTTED: {
-        *name = p->kstr[GETARG_U(i)]->str;
+        *name = getstr(p->kstr[GETARG_U(i)]);
         return "field";
       }
       default:

lfunc.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lfunc.c,v 1.38 2001/01/29 19:34:02 roberto Exp roberto $
+** $Id: lfunc.c,v 1.39 2001/02/01 17:40:48 roberto Exp roberto $
 ** Auxiliary functions to manipulate prototypes and closures
 ** See Copyright Notice in lua.h
 */
@@ -79,7 +79,7 @@ const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
     if (pc < f->locvars[i].endpc) {  /* is variable active? */
       local_number--;
       if (local_number == 0)
-        return f->locvars[i].varname->str;
+        return getstr(f->locvars[i].varname);
     }
   }
   return NULL;  /* not found */

llex.c

@@ -1,5 +1,5 @@
 /*
-** $Id: llex.c,v 1.75 2001/01/15 18:07:56 roberto Exp roberto $
+** $Id: llex.c,v 1.76 2001/01/19 13:20:30 roberto Exp roberto $
 ** Lexical Analyzer
 ** See Copyright Notice in lua.h
 */
@@ -55,7 +55,7 @@ void luaX_checklimit (LexState *ls, int val, int limit, const char *msg) {
 
 void luaX_syntaxerror (LexState *ls, const char *s, const char *token) {
   char buff[MAXSRC];
-  luaO_chunkid(buff, ls->source->str, sizeof(buff));
+  luaO_chunkid(buff, getstr(ls->source), sizeof(buff));
   luaO_verror(ls->L, "%.99s;\n  last token read: `%.30s' at line %d in %.80s",
               s, token, ls->linenumber, buff);
 }

lobject.h

@@ -1,5 +1,5 @@
 /*
-** $Id: lobject.h,v 1.93 2001/02/02 15:13:05 roberto Exp roberto $
+** $Id: lobject.h,v 1.94 2001/02/02 16:32:00 roberto Exp roberto $
 ** Type definitions for Lua objects
 ** See Copyright Notice in lua.h
 */
@@ -57,7 +57,6 @@ typedef struct lua_TObject {
 #define clvalue(o)      ((o)->value.cl)
 #define hvalue(o)       ((o)->value.h)
 #define infovalue(o)	((o)->value.info)
-#define svalue(o)       (tsvalue(o)->str)
 
 
 /* Macros to set values */
@@ -91,13 +90,6 @@ typedef struct lua_TObject {
 ** String headers for string table
 */
 
-/*
-** most `malloc' libraries allocate memory in blocks of 8 bytes. TSPACK
-** tries to make sizeof(TString) a multiple of this granularity, to reduce
-** waste of space.
-*/
-#define TSPACK	((int)sizeof(int))
-
 typedef struct TString {
   union {
     struct {  /* for strings */
@@ -112,10 +104,23 @@ typedef struct TString {
   size_t len;
   int marked;
   struct TString *nexthash;  /* chain for hash table */
-  char str[TSPACK];   /* variable length string!! must be the last field! */
 } TString;
 
 
+/*
+** type equivalent to TString, but with maximum alignment requirements
+*/
+union L_UTString {
+  TString ts;
+  union L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */
+};
+
+
+
+#define getstr(ts)	((char *)(ts) + sizeof(union L_UTString))
+#define svalue(o)       getstr(tsvalue(o))
+
+
 /*
 ** Function Prototypes
 */

lparser.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.c,v 1.130 2001/02/08 11:19:10 roberto Exp roberto $
+** $Id: lparser.c,v 1.131 2001/02/09 18:37:33 roberto Exp roberto $
 ** LL(1) Parser and code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -209,7 +209,7 @@ static int search_local (LexState *ls, TString *n, expdesc *var) {
 static void singlevar (LexState *ls, TString *n, expdesc *var) {
   int level = search_local(ls, n, var);
   if (level >= 1)  /* neither local (0) nor global (-1)? */
-    luaX_syntaxerror(ls, "cannot access a variable in outer scope", n->str);
+    luaX_syntaxerror(ls, "cannot access a variable in outer scope", getstr(n));
   else if (level == -1)  /* global? */
     var->u.index = string_constant(ls->fs, n);
 }
@@ -235,12 +235,12 @@ static void pushupvalue (LexState *ls, TString *n) {
   int level = search_local(ls, n, &v);
   if (level == -1) {  /* global? */
     if (fs->prev == NULL)
-      luaX_syntaxerror(ls, "cannot access an upvalue at top level", n->str);
+      luaX_syntaxerror(ls, "cannot access an upvalue at top level", getstr(n));
     v.u.index = string_constant(fs->prev, n);
   }
   else if (level != 1)
     luaX_syntaxerror(ls,
-         "upvalue must be global or local to immediately outer scope", n->str);
+      "upvalue must be global or local to immediately outer scope", getstr(n));
   luaK_code1(fs, OP_PUSHUPVALUE, indexupvalue(ls, &v));
 }
 

lstring.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lstring.c,v 1.55 2001/02/01 17:40:48 roberto Exp roberto $
+** $Id: lstring.c,v 1.56 2001/02/09 19:53:16 roberto Exp roberto $
 ** String table (keeps all strings handled by Lua)
 ** See Copyright Notice in lua.h
 */
@@ -71,7 +71,7 @@ TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
   for (l1=l; l1>=step; l1-=step)  /* compute hash */
     h = h ^ ((h<<5)+(h>>2)+(unsigned char)str[l1-1]);
   for (ts = G(L)->strt.hash[lmod(h, G(L)->strt.size)]; ts; ts = ts->nexthash) {
-    if (ts->len == l && (memcmp(str, ts->str, l) == 0))
+    if (ts->len == l && (memcmp(str, getstr(ts), l) == 0))
       return ts;
   }
   /* not found */
@@ -81,8 +81,8 @@ TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
   ts->len = l;
   ts->u.s.hash = h;
   ts->u.s.constindex = 0;
-  memcpy(ts->str, str, l);
-  ts->str[l] = 0;  /* ending 0 */
+  memcpy(getstr(ts), str, l);
+  getstr(ts)[l] = 0;  /* ending 0 */
   newentry(L, &G(L)->strt, ts, lmod(h, G(L)->strt.size));  /* insert it */
   return ts;
 }

lstring.h

@@ -1,5 +1,5 @@
 /*
-** $Id: lstring.h,v 1.27 2001/01/10 17:41:50 roberto Exp roberto $
+** $Id: lstring.h,v 1.28 2001/02/09 19:53:16 roberto Exp roberto $
 ** String table (keep all strings handled by Lua)
 ** See Copyright Notice in lua.h
 */
@@ -13,16 +13,6 @@
 
 
 
-/*
-** type equivalent to TString, but with maximum alignment requirements
-*/
-union L_UTString {
-  TString ts;
-  union L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */
-};
-
-
-
 /*
 ** any TString with mark>=FIXMARK is never collected.
 ** Marks>=RESERVEDMARK are used to identify reserved words.
@@ -31,8 +21,7 @@ union L_UTString {
 #define RESERVEDMARK	3
 
 
-#define sizestring(l)	((lint32)sizeof(TString) + \
-                         ((lint32)(l+1)-TSPACK)*(lint32)sizeof(char))
+#define sizestring(l)	((luint32)sizeof(union L_UTString)+(l)+1)
 
 #define sizeudata(l)	((luint32)sizeof(union L_UTString)+(l))
 

ltests.c

@@ -1,5 +1,5 @@
 /*
-** $Id: ltests.c,v 1.64 2001/02/06 18:18:58 roberto Exp roberto $
+** $Id: ltests.c,v 1.65 2001/02/09 19:53:16 roberto Exp roberto $
 ** Internal Module for Debugging of the Lua Implementation
 ** See Copyright Notice in lua.h
 */
@@ -201,7 +201,7 @@ static int liststrings (lua_State *L) {
   lua_newtable(L);
   for (i=0; i<p->sizekstr; i++) {
     lua_pushnumber(L, i+1);
-    lua_pushstring(L, p->kstr[i]->str);
+    lua_pushstring(L, getstr(p->kstr[i]));
     lua_settable(L, -3);
   }
   return 1;
@@ -537,7 +537,9 @@ static int testC (lua_State *L) {
       lua_pushnumber(L, lua_tonumber(L, getnum));
     }
     else if EQ("tostring") {
-      lua_pushstring(L, lua_tostring(L, getnum));
+      const char *s = lua_tostring(L, getnum);
+      lua_assert((unsigned long)s % 4 == 0);  /* check alignment */
+      lua_pushstring(L, s);
     }
     else if EQ("tonumber") {
       lua_pushnumber(L, lua_tonumber(L, getnum));

ltm.c

@@ -1,5 +1,5 @@
 /*
-** $Id: ltm.c,v 1.64 2001/01/26 11:45:51 roberto Exp roberto $
+** $Id: ltm.c,v 1.65 2001/02/02 15:13:05 roberto Exp roberto $
 ** Tag methods
 ** See Copyright Notice in lua.h
 */
@@ -150,7 +150,7 @@ const char *luaT_typename (global_State *G, const TObject *o) {
   ts = G->TMtable[tag].name;
   if (ts == NULL)
     ts = G->TMtable[t].name;
-  return ts->str;
+  return getstr(ts);
 }
 
 

ltm.h

@@ -1,5 +1,5 @@
 /*
-** $Id: ltm.h,v 1.21 2001/01/24 16:20:54 roberto Exp roberto $
+** $Id: ltm.h,v 1.22 2001/01/25 16:45:36 roberto Exp roberto $
 ** Tag methods
 ** See Copyright Notice in lua.h
 */
@@ -62,7 +62,7 @@ struct TM {
 #define luaT_gettm(G,tag,event) (G->TMtable[tag].method[event])
 #define luaT_gettmbyObj(G,o,e)  (luaT_gettm((G),luaT_tag(o),(e)))
 
-#define basictypename(G, t)	(G->TMtable[t].name->str)
+#define basictypename(G, t)	getstr(G->TMtable[t].name)
 
 
 #define validtag(G,t) (NUM_TAGS <= (t) && (t) < G->ntag)

lvm.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 1.166 2001/02/07 18:13:49 roberto Exp roberto $
+** $Id: lvm.c,v 1.167 2001/02/09 18:07:47 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -225,9 +225,9 @@ static void call_arith (lua_State *L, StkId p1, TMS event) {
 
 
 static int luaV_strlessthan (const TString *ls, const TString *rs) {
-  const char *l = ls->str;
+  const char *l = getstr(ls);
   size_t ll = ls->len;
-  const char *r = rs->str;
+  const char *r = getstr(rs);
   size_t lr = rs->len;
   for (;;) {
     int temp = strcoll(l, r);
@@ -281,7 +281,7 @@ void luaV_strconc (lua_State *L, int total, StkId top) {
       tl = 0;
       for (i=n; i>0; i--) {  /* concat all strings */
         size_t l = tsvalue(top-i)->len;
-        memcpy(buffer+tl, tsvalue(top-i)->str, l);
+        memcpy(buffer+tl, svalue(top-i), l);
         tl += l;
       }
       setsvalue(top-n, luaS_newlstr(L, buffer, tl));