nik/lush
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

type 'TString' refers directly to the structure inside the union

Browse Source 
(union used only for size purposes)
This commit is contained in:
Roberto Ierusalimschy
2014-07-18 10:36:14 -03:00
parent 3511e186cd
commit ca41b43f53
13 changed files with 102 additions and 104 deletions
Download Patch File Download Diff File Expand all files Collapse all files

43
lobject.h
View File

@@ -1,5 +1,5 @@
/*
** $Id: lobject.h,v 2.96 2014/07/17 17:27:49 roberto Exp roberto $
** $Id: lobject.h,v 2.97 2014/07/18 12:17:54 roberto Exp roberto $
** Type definitions for Lua objects
** See Copyright Notice in lua.h
*/
@@ -156,8 +156,7 @@ typedef struct lua_TValue TValue;
#define fltvalue(o) check_exp(ttisfloat(o), val_(o).n)
#define gcvalue(o) check_exp(iscollectable(o), val_(o).gc)
#define pvalue(o) check_exp(ttislightuserdata(o), val_(o).p)
#define rawtsvalue(o) check_exp(ttisstring(o), rawgco2ts(val_(o).gc))
#define tsvalue(o) (&rawtsvalue(o)->tsv)
#define tsvalue(o) check_exp(ttisstring(o), gco2ts(val_(o).gc))
#define rawuvalue(o) check_exp(ttisfulluserdata(o), rawgco2u(val_(o).gc))
#define uvalue(o) (&rawuvalue(o)->uv)
#define clvalue(o) check_exp(ttisclosure(o), gco2cl(val_(o).gc))
@@ -210,7 +209,7 @@ typedef struct lua_TValue TValue;
#define setsvalue(L,obj,x) \
{ TValue *io = (obj); TString *x_ = (x); \
val_(io).gc = obj2gco(&x_->tsv); settt_(io, ctb(x_->tsv.tt)); \
val_(io).gc = obj2gco(x_); settt_(io, ctb(x_->tt)); \
checkliveness(G(L),io); }
#define setuvalue(L,obj,x) \
@@ -299,24 +298,36 @@ typedef TValue *StkId; /* index to stack elements */
/*
** Header for string value; string bytes follow the end of this structure
** (aligned according to 'UTString'; see next).
*/
typedef union TString {
L_Umaxalign dummy; /* ensures maximum alignment for strings */
struct {
CommonHeader;
lu_byte extra; /* reserved words for short strings; "has hash" for longs */
unsigned int hash;
size_t len; /* number of characters in string */
union TString *hnext; /* linked list for hash table */
} tsv;
typedef struct TString {
CommonHeader;
lu_byte extra; /* reserved words for short strings; "has hash" for longs */
unsigned int hash;
size_t len; /* number of characters in string */
struct TString *hnext; /* linked list for hash table */
} TString;
/* get the actual string (array of bytes) from a TString */
#define getstr(ts) cast(const char *, (ts) + 1)
/*
** Ensures that address after this type is always fully aligned.
*/
typedef union UTString {
L_Umaxalign dummy; /* ensures maximum alignment for strings */
TString tsv;
} UTString;
/*
** Get the actual string (array of bytes) from a 'TString'.
** (Access to 'extra' ensures that value is really a 'TString'.)
*/
#define getaddrstr(ts) (cast(char *, (ts)) + sizeof(UTString))
#define getstr(ts) \
((void)(ts)->extra, cast(const char*, getaddrstr(ts)))
/* get the actual string (array of bytes) from a Lua value */
#define svalue(o) getstr(rawtsvalue(o))
#define svalue(o) getstr(tsvalue(o))
/*