nvalue sanitisation part 4 (re: 0686c70, 0ebaab3, 6cdc2dc)

This commit takes a large first step towards getting rid of 'union
Value' altogether, by turning the nvalue member of the Namval_t
struct into a void pointer instead of a union Value pointer.
(Also, it is now defined entirely in nval.h, eliminating the
_NV_PRIVATE part from name.h).

So, for all those Namval_t* pointers such as np, instead of
np->nvalue.cp, np->nvalue.lp, etc., we now simply use np->nvalue.

The code everywhere is correspondingly updated to do local
typecasts where the nvalue pointer is dereferenced. Sometimes,
explicit typecasts seemed the most practical, other times I've
preferred implicit typecasts through assigning np->nvalue to an
appropriately typed local pointer variable and dereferencing that.

On the other hand, this change has alllowed getting rid of many
explicit typecasts as well, as C90 void pointers are typeless and
cna be implicitly typecast to any type.

In my view, this change is already increasing the consistency,
legibility and transparency of the name-value handling in the code.
When I was new to this code base (and still pretty new to C), I
found the nvalue union usage one of the most mystifying aspects.
The code now shows more explicitly what is being done.

src/cmd/ksh93/bltins/cd_pwd.c

@@ -41,7 +41,7 @@
  */
 static void rehash(Namval_t *np,void *data)
 {
-	Pathcomp_t *pp = (Pathcomp_t*)np->nvalue.cp;
+	Pathcomp_t *pp = np->nvalue;
 	if(pp && *pp->name!='/')
 		nv_rehash(np,data);
 }
@@ -135,7 +135,7 @@ int	b_cd(int argc, char *argv[],Shbltin_t *context)
 	&& !(dir[0]=='.' && (dir[1]=='/' || dir[1]==0))
 	&& !(dir[0]=='.' && dir[1]=='.' && (dir[2]=='/' || dir[2]==0)))
 	{
-		if((dp=sh_scoped(CDPNOD)->nvalue.cp) && !(cdpath = (Pathcomp_t*)sh.cdpathlist))
+		if((dp=sh_scoped(CDPNOD)->nvalue) && !(cdpath = (Pathcomp_t*)sh.cdpathlist))
 		{
 			if(cdpath=path_addpath(NULL,dp,PATH_CDPATH))
 				sh.cdpathlist = cdpath;

src/cmd/ksh93/bltins/misc.c

@@ -266,10 +266,10 @@ int    b_dot_cmd(int n,char *argv[],Shbltin_t *context)
 		np = nv_search(script,sh.fun_tree,0);
 		if(np && is_afunction(np) && !nv_isattr(np,NV_FPOSIX) && !(sh_isoption(SH_POSIX) && context->bnode==SYSDOT))
 		{
-			if(!np->nvalue.ip)
+			if(!np->nvalue)
 			{
 				path_search(script,NULL,0);
-				if(np->nvalue.ip)
+				if(np->nvalue)
 				{
 					if(nv_isattr(np,NV_FPOSIX))
 						np = 0;
@@ -307,7 +307,7 @@ int    b_dot_cmd(int n,char *argv[],Shbltin_t *context)
 	prevscope->save_tree = sh.var_tree;
 	tofree = sh.st.filename;
 	if(np)
-		sh.st.filename = np->nvalue.rp->fname;
+		sh.st.filename = ((struct Ufunction*)np->nvalue)->fname;
 	nv_putval(SH_PATHNAMENOD, sh.st.filename ,NV_NOFREE);
 	sh.posix_fun = 0;
 	if(np || argv[1])

src/cmd/ksh93/bltins/print.c

@@ -672,7 +672,7 @@ static ssize_t fmtbase64(Sfio_t *iop, char *string, int alt)
 				nv_offattr(np,NV_RAW);
 			}
 			else
-				cp = (char*)np->nvalue.cp;
+				cp = np->nvalue;
 			if((size = n)==0)
 				size = strlen(cp);
 			size = sfwrite(iop, cp, size);
@@ -844,15 +844,15 @@ static int extend(Sfio_t* sp, void* v, Sffmt_t* fe)
 			np = nv_open(argp,sh.var_tree,NV_VARNAME|NV_NOARRAY);
 			_nv_unset(np,0);
 			nv_onattr(np,NV_INTEGER);
-			if (np->nvalue.lp = new_of(int32_t,0))
-				*np->nvalue.lp = 0;
+			if (np->nvalue = new_of(int32_t,0))
+				*((int32_t*)np->nvalue) = 0;
 			nv_setsize(np,10);
 			if(sizeof(int)==sizeof(int32_t))
-				value->ip = (int*)np->nvalue.lp;
+				value->ip = np->nvalue;
 			else
 			{
 				int32_t sl = 1;
-				value->ip = (int*)(((char*)np->nvalue.lp) + (*((char*)&sl) ? 0 : sizeof(int)));
+				value->ip = (int*)(((char*)np->nvalue) + (*((char*)&sl) ? 0 : sizeof(int)));
 			}
 			break;
 		}

src/cmd/ksh93/bltins/read.c

@@ -487,8 +487,8 @@ int sh_readline(char **names, volatile int fd, int flags, ssize_t size, Sflong_t
 #else
 			int optimize = 1;
 #endif
-			if(optimize && c==size && np->nvalue.cp && !nv_isarray(np))
-				memcpy((char*)np->nvalue.cp,var,c);
+			if(optimize && c==size && np->nvalue && !nv_isarray(np))
+				memcpy(np->nvalue,var,c);
 			else
 			{
 				Namval_t *mp;

src/cmd/ksh93/bltins/test.c

@@ -463,7 +463,7 @@ int test_unop(int op,const char *arg)
 			return isref;
 		if(isref)
 		{
-			if(np->nvalue.cp)
+			if(np->nvalue)
 				np = nv_refnode(np);
 			else
 				return 0;

src/cmd/ksh93/bltins/typeset.c

@@ -518,7 +518,10 @@ int    b_typeset(int argc,char *argv[],Shbltin_t *context)
 	if(flag&NV_TYPE)
 	{
 		Stk_t *stkp = sh.stk;
-		int off=0,offset = stktell(stkp);
+#if SHOPT_NAMESPACE
+		int off = 0;
+#endif /* SHOPT_NAMESPACE */
+		int offset = stktell(stkp);
 		if(!tdata.prefix)
 			return sh_outtype(sfstdout);
 		sfputr(stkp,NV_CLASS,-1);
@@ -648,7 +651,9 @@ static int     setall(char **argv,int flag,Dt_t *troot,struct tdata *tp)
 	int nvflags=(flag&(NV_ARRAY|NV_NOARRAY|NV_VARNAME|NV_IDENT|NV_ASSIGN|NV_STATIC|NV_MOVE));
 	int r=0, ref=0, comvar=(flag&NV_COMVAR),iarray=(flag&NV_IARRAY);
 	Dt_t *save_vartree = NULL;
+#if SHOPT_NAMESPACE
 	Namval_t *save_namespace = NULL;
+#endif
 	if(flag&NV_GLOBAL)
 	{
 		save_vartree = sh.var_tree;
@@ -757,8 +762,8 @@ static int     setall(char **argv,int flag,Dt_t *troot,struct tdata *tp)
 						np = nv_search(stkptr(sh.stk,offset),troot,0);
 						stkseek(sh.stk,offset);
 					}
-					if(np && np->nvalue.cp) 
-						np->nvalue.rp->help = tp->help;
+					if(np && np->nvalue) 
+						((struct Ufunction*)np->nvalue)->help = tp->help;
 				}
 				continue;
 			}
@@ -1420,7 +1425,7 @@ static int unall(int argc, char **argv, Dt_t *troot)
 			{
 				if(troot!=sh.fun_base)
 					np->nvflag = 0;	/* invalidate */
-				else if(!(np->nvalue.rp && np->nvalue.rp->running))
+				else if(!(np->nvalue && ((struct Ufunction*)np->nvalue)->running))
 					nv_delete(np,troot,0);
 			}
 			/* The alias has been unset by call to _nv_unset, remove it from the tree */
@@ -1488,9 +1493,10 @@ static int print_namval(Sfio_t *file,Namval_t *np,int flag, struct tdata *tp)
 	if(isfun)
 	{
 		char *fname=0;
+		struct Ufunction *rp = np->nvalue;
 		if(nv_isattr(np,NV_NOFREE))
 			return 0;
-		if(!flag && !np->nvalue.ip)
+		if(!flag && !rp)
 			sfputr(file,"typeset -fu",' ');
 		else if(!flag && !nv_isattr(np,NV_FPOSIX))
 			sfputr(file,"function",' ');
@@ -1500,28 +1506,28 @@ static int print_namval(Sfio_t *file,Namval_t *np,int flag, struct tdata *tp)
 		sfputr(file,cp,-1);
 		if(nv_isattr(np,NV_FPOSIX))
 			sfwrite(file,"()",2);
-		else if(np->nvalue.rp)
+		else if(rp)
 		{
 			int i;
 			/* output function reference list (for .sh.math.* functions) */
-			for(i = 0; i < np->nvalue.rp->argc; i++)
-				sfprintf(file," %s",np->nvalue.rp->argv[i]);
+			for(i = 0; i < rp->argc; i++)
+				sfprintf(file," %s",rp->argv[i]);
 		}
-		if(np->nvalue.rp && nv_funtree(np))
-			fname = np->nvalue.rp->fname;
+		if(rp && rp->ptree)
+			fname = rp->fname;
 		else
 			flag = '\n';
 		if(flag)
 		{
-			if(tp->pflag && np->nvalue.rp && nv_funtree(np))
-				sfprintf(file," #line %d %s\n", np->nvalue.rp->lineno, fname ? sh_fmtq(fname) : Empty);
+			if(tp->pflag && rp && rp->ptree)
+				sfprintf(file," #line %d %s\n", rp->lineno, fname ? sh_fmtq(fname) : Empty);
 			else
 				sfputc(file, '\n');
 		}
 		else
 		{
 			sfputc(file, '\n');
-			sh_deparse(file, (Shnode_t*)(nv_funtree(np)), 2 | nv_isattr(np,NV_FPOSIX), 0);
+			sh_deparse(file, (Shnode_t*)(rp->ptree), 2 | nv_isattr(np,NV_FPOSIX), 0);
 		}
 		return nv_size(np) + 1;
 	}

src/cmd/ksh93/edit/history.c

@@ -330,7 +330,7 @@ int  sh_histinit(void)
 		hp = hist_trim(hp,(int)hp->histind-maxlines);
 	}
 	sfdisc(hp->histfp,&hp->histdisc);
-	(HISTCUR)->nvalue.lp = (&hp->histind);
+	HISTCUR->nvalue = &hp->histind;
 	sh_timeradd(1000L*(HIST_RECENT-30), 1, hist_touch, hp->histname);
 #if SHOPT_ACCTFILE
 	if(sh_isstate(SH_INTERACTIVE))

src/cmd/ksh93/features/externs

@@ -166,11 +166,11 @@ tst	note{ determining size of PID variables }end output{
 		 * If there is ever a system where this test returns 1, then both this
 		 * test and nv_getval() must learn a new integer size attribute.
 		 */
-		if(s==sizeof(int16_t))		/* union Value: sp */
+		if(s==sizeof(int16_t))
 			a="NV_INTEGER|NV_SHORT";
-		else if(s==sizeof(int32_t))	/* union Value: lp */
+		else if(s==sizeof(int32_t))
 			a="NV_INTEGER";
-		else if(s==sizeof(Sflong_t))	/* union Value: llp */
+		else if(s==sizeof(Sflong_t))
 			a="NV_INTEGER|NV_LONG";
 		else
 			return 1;

src/cmd/ksh93/include/name.h

@@ -16,16 +16,12 @@
 *         hyenias <[email protected]>          *
 *                                                                      *
 ***********************************************************************/
-#ifndef _NV_PRIVATE
+#ifndef name_h_defined
+#define name_h_defined
 /*
  * This is the implementation header file for name-value pairs
  */
 
-#define _NV_PRIVATE	\
-	Namfun_t	*nvfun;		/* pointer to trap functions */ \
-	union Value	nvalue; 	/* value field */ \
-	void		*nvmeta;	/* pointer to any of various kinds of type-dependent data */
-
 #include	<ast.h>
 #include	<cdt.h>
 
@@ -135,21 +131,21 @@ struct Ufunction
 #define nv_isref(n)	(nv_isattr((n),NV_REF|NV_TAGGED|NV_FUNCT)==NV_REF)
 #define is_abuiltin(n)	(nv_isattr(n,NV_BLTIN|NV_INTEGER)==NV_BLTIN)
 #define is_afunction(n)	(nv_isattr(n,NV_FUNCTION|NV_REF)==NV_FUNCTION)
-#define	nv_funtree(n)	((n)->nvalue.rp->ptree)
+#define	nv_funtree(n)	(((struct Ufunction*)(n)->nvalue)->ptree)
 
 /* NAMNOD MACROS */
 /* ... for attributes */
 
 #define nv_setattr(n,f)	((n)->nvflag = (f))
 #define nv_context(n)	((void*)(n)->nvfun)		/* for builtins */
 /* The following are for name references */
-#define nv_refnode(n)	((n)->nvalue.nrp->np)
-#define nv_reftree(n)	((n)->nvalue.nrp->root)
-#define nv_reftable(n)	((n)->nvalue.nrp->table)
-#define nv_refsub(n)	((n)->nvalue.nrp->sub)
+#define nv_refnode(n)	(((struct Namref*)(n)->nvalue)->np)
+#define nv_reftree(n)	(((struct Namref*)(n)->nvalue)->root)
+#define nv_reftable(n)	(((struct Namref*)(n)->nvalue)->table)
+#define nv_refsub(n)	(((struct Namref*)(n)->nvalue)->sub)
 #if SHOPT_FIXEDARRAY
-#   define nv_refindex(n)	((n)->nvalue.nrp->curi)
-#   define nv_refdimen(n)	((n)->nvalue.nrp->dim)
+#   define nv_refindex(n)	(((struct Namref*)(n)->nvalue)->curi)
+#   define nv_refdimen(n)	(((struct Namref*)(n)->nvalue)->dim)
 #endif /* SHOPT_FIXEDARRAY */
 
 /* ... etc */
@@ -158,7 +154,7 @@ struct Ufunction
 #undef nv_size
 #define nv_size(np)	((np)->nvsize)
 #define _nv_hasget(np)  ((np)->nvfun && (np)->nvfun->disc && nv_hasget(np))
-#define nv_isnull(np)	(!(np)->nvalue.cp && !_nv_hasget(np))
+#define nv_isnull(np)	(!(np)->nvalue && !_nv_hasget(np))
 
 /* ...	for arrays */
 
@@ -262,4 +258,4 @@ extern const char	e_typecompat[];
 extern const char	e_globalref[];
 extern const char	e_tolower[];
 extern const char	e_toupper[];
-#endif /* _NV_PRIVATE */
+#endif /* name_h_defined */

src/cmd/ksh93/include/nval.h

@@ -118,13 +118,9 @@ struct Namval
 	unsigned short	nvflag; 	/* attributes */
 	unsigned short 	nvsize;		/* size or base */
 #endif
-#ifdef _NV_PRIVATE
-	_NV_PRIVATE
-#else
-	Namfun_t	*nvfun;
-	char		*nvalue;
-	char		*nvprivate;
-#endif /* _NV_PRIVATE */
+	Namfun_t	*nvfun;		/* pointer to trap functions */
+	void		*nvalue;	/* pointer to any kind of value */
+	void		*nvmeta;	/* pointer to any of various kinds of type-dependent data */
 };
 
 #define NV_CLASS	".sh.type"

src/cmd/ksh93/include/shell.h

@@ -51,7 +51,7 @@ typedef struct Shell_s Shell_t;
 #include	<shcmd.h>
 
 /* get pointer to a built-in command's entry function */
-#define	funptr(n)	((Shbltin_f)(n)->nvalue.bfp)
+#define	funptr(n)	((Shbltin_f)(n)->nvalue)
 
 typedef void	(*Shinit_f)(Shell_t*, int);
 #ifndef SH_wait_f_defined

src/cmd/ksh93/include/version.h

@@ -18,7 +18,7 @@
 
 #define SH_RELEASE_FORK	"93u+m"		/* only change if you develop a new ksh93 fork */
 #define SH_RELEASE_SVER	"1.1.0-alpha"	/* semantic version number: https://semver.org */
-#define SH_RELEASE_DATE	"2024-11-28"	/* must be in this format for $((.sh.version)) */
+#define SH_RELEASE_DATE	"2024-11-29"	/* must be in this format for $((.sh.version)) */
 #define SH_RELEASE_CPYR	"(c) 2020-2024 Contributors to ksh " SH_RELEASE_FORK
 
 /* Scripts sometimes field-split ${.sh.version}, so don't change amount of whitespace. */

src/cmd/ksh93/sh/arith.c

@@ -80,7 +80,7 @@ static Namval_t *scope(Namval_t *np,struct lval *lvalue,int assign)
 		&& sh_macfun(cp, offset = stktell(sh.stk)))
 		{
 			Fun = sh_arith(sub=stkptr(sh.stk,offset));
-			FunNode.nvalue.ldp = &Fun;
+			FunNode.nvalue = &Fun;
 			nv_onattr(&FunNode,NV_NOFREE|NV_LDOUBLE|NV_RDONLY);
 			cp[flag] = c;
 			return &FunNode;
@@ -330,9 +330,10 @@ static Sfdouble_t arith(const char **ptr, struct lval *lvalue, int type, Sfdoubl
 				stkseek(sh.stk,off);
 				if(np=nv_search(stkptr(sh.stk,off),sh.fun_tree,0))
 				{
-						lvalue->nargs = -np->nvalue.rp->argc;
-						lvalue->fun = (Math_f)np;
-						break;
+					struct Ufunction *rp = np->nvalue;
+					lvalue->nargs = -rp->argc;
+					lvalue->fun = (Math_f)np;
+					break;
 				}
 				if(fsize<=(sizeof(tp->fname)-2))
 					lvalue->fun = (Math_f)sh_mathstdfun(*ptr,fsize,&lvalue->nargs);
@@ -385,14 +386,14 @@ static Sfdouble_t arith(const char **ptr, struct lval *lvalue, int type, Sfdoubl
 				if(!sh_isoption(SH_POSIX) && (cp[0] == 'i' || cp[0] == 'I') && (cp[1] == 'n' || cp[1] == 'N') && (cp[2] == 'f' || cp[2] == 'F') && cp[3] == 0)
 				{
 					Inf = strtold("Inf", NULL);
-					Infnod.nvalue.ldp = &Inf;
+					Infnod.nvalue = &Inf;
 					np = &Infnod;
 					nv_onattr(np,NV_NOFREE|NV_LDOUBLE|NV_RDONLY);
 				}
 				else if(!sh_isoption(SH_POSIX) && (cp[0] == 'n' || cp[0] == 'N') && (cp[1] == 'a' || cp[1] == 'A') && (cp[2] == 'n' || cp[2] == 'N') && cp[3] == 0)
 				{
 					NaN = strtold("NaN", NULL);
-					NaNnod.nvalue.ldp = &NaN;
+					NaNnod.nvalue = &NaN;
 					np = &NaNnod;
 					nv_onattr(np,NV_NOFREE|NV_LDOUBLE|NV_RDONLY);
 				}