Streamline some nval(3) and related flaggery

In the olden days, ksh used the hash(3) library to store variables,
aliases, functions, etc. For many years, it's been using the cdt(3)
library instead. But the low-level nv_search() name-value tree
lookup function was still repurposing some bit flags from the old
hash API for its options, though that API is otherwise unused.

So we were still including the entire obsolete <hash.h> API just
to use two repurposed HASH_* bit flags for nv_search(). This commit
makes nv_search() repurpose some flags from <nval.h> instead.

This commit should not change ksh's behaviour.

src/cmd/ksh93/sh/nvdisc.c:
- Make nv_search() use NV_NOSCOPE instead of HASH_NOSCOPE and
  NV_REF instead of HASH_BUCKET.
- The HASH_SCOPE flag was also passed to some nv_search() calls,
  but nv_search() ignores it, so that flag is deleted from those.
- Document nv_search() in a comment.

src/cmd/ksh93/include/name.h:
- Move NV_UNATTR to nval.h to join the other nv_open() options
  there. (re: 1184b2a)

src/cmd/ksh93/include/nval.h:
- Since we no longer use HASH_* macros, do not include <hash.h>.
- Remove unused NV_NOASSIGN macro, defined to 0. This was there
  for "backward compatibility" since before 1995; long enough.

src/cmd/ksh93/include/shell.h:
- Bump SH_VERSION due to the nv_search() API change (even though no
  changes were made to the APIs documented in nval.3 or shell.3).

All other changed files:
- Update to match the flaggery changes.

src/cmd/ksh93/Mamfile

@@ -198,10 +198,6 @@ make install
 					done ${PACKAGE_ast_INCLUDE}/cmd.h dontcare
 					prev ${PACKAGE_ast_INCLUDE}/shcmd.h implicit
 					make include/nval.h implicit
-						make ${PACKAGE_ast_INCLUDE}/hash.h implicit
-							make ${PACKAGE_ast_INCLUDE}/hashpart.h implicit
-							done ${PACKAGE_ast_INCLUDE}/hashpart.h dontcare
-						done ${PACKAGE_ast_INCLUDE}/hash.h dontcare
 						prev ${PACKAGE_ast_INCLUDE}/option.h implicit
 						make ${PACKAGE_ast_INCLUDE}/cdt.h implicit
 							prev ${PACKAGE_ast_INCLUDE}/ast_common.h implicit

src/cmd/ksh93/bltins/getopts.c

@@ -91,7 +91,7 @@ int	b_getopts(int argc,char *argv[],Shbltin_t *context)
 	error_info.context->flags |= ERROR_SILENT;
 	error_info.id = options;
 	options = argv[0];
-	np = nv_open(argv[1],sh.var_tree,NV_NOASSIGN|NV_VARNAME);
+	np = nv_open(argv[1],sh.var_tree,NV_VARNAME);
 	if(argc>2)
 	{
 		argv +=1;

src/cmd/ksh93/bltins/mkservice.c

@@ -454,7 +454,7 @@ int	b_mkservice(int argc, char** argv, Shbltin_t *context)
 		close(fd);
 	else
 		sp->fd = fd;
-	np = nv_open(var,sh.var_tree,NV_ARRAY|NV_VARNAME|NV_NOASSIGN);
+	np = nv_open(var,sh.var_tree,NV_ARRAY|NV_VARNAME);
 	sp->node = np;
 	nv_putval(np, path, 0); 
 	nv_stack(np, (Namfun_t*)sp);

src/cmd/ksh93/bltins/print.c

@@ -558,7 +558,7 @@ static ssize_t fmtbase64(Sfio_t *iop, char *string, int alt)
 	char			*cp;
 	Sfdouble_t		d;
 	ssize_t			size;
-	Namval_t		*np = nv_open(string, NiL, NV_VARNAME|NV_NOASSIGN|NV_NOADD);
+	Namval_t		*np = nv_open(string, NiL, NV_VARNAME|NV_NOADD);
 	Namarr_t		*ap;
 	static union types_t	number;
 	if(!np || nv_isnull(np))
@@ -795,7 +795,7 @@ static int extend(Sfio_t* sp, void* v, Sffmt_t* fe)
 		case 'n':
 		{
 			Namval_t *np;
-			np = nv_open(argp,sh.var_tree,NV_VARNAME|NV_NOASSIGN|NV_NOARRAY);
+			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))

src/cmd/ksh93/bltins/read.c

@@ -801,7 +801,7 @@ int sh_readline(char **names, volatile int fd, int flags, ssize_t size, long tim
 		{
 			if(name)
 			{
-				np = nv_open(name,sh.var_tree,NV_NOASSIGN|NV_VARNAME);
+				np = nv_open(name,sh.var_tree,NV_VARNAME);
 				name = *++names;
 			}
 			else

src/cmd/ksh93/bltins/typeset.c

@@ -529,12 +529,12 @@ int    b_typeset(int argc,register char *argv[],Shbltin_t *context)
 		if(NV_CLASS[sizeof(NV_CLASS)-2]!='.')
 			sfputc(stkp,'.');
 		sfputr(stkp,tdata.prefix,0);
-		tdata.tp = nv_open(stkptr(stkp,offset),sh.var_tree,NV_VARNAME|NV_NOARRAY|NV_NOASSIGN);
+		tdata.tp = nv_open(stkptr(stkp,offset),sh.var_tree,NV_VARNAME|NV_NOARRAY);
 #if SHOPT_NAMESPACE
 		if(!tdata.tp && off)
 		{
 			*stkptr(stkp,off)=0;
-			tdata.tp = nv_open(stkptr(stkp,offset),sh.var_tree,NV_VARNAME|NV_NOARRAY|NV_NOASSIGN);
+			tdata.tp = nv_open(stkptr(stkp,offset),sh.var_tree,NV_VARNAME|NV_NOARRAY);
 		}
 #endif /* SHOPT_NAMESPACE */
 		stkseek(stkp,offset);
@@ -699,7 +699,7 @@ static int     setall(char **argv,register int flag,Dt_t *troot,struct tdata *tp
 					}
 #if SHOPT_NAMESPACE
 					if(sh.namespace)
-						np = sh_fsearch(name,NV_ADD|HASH_NOSCOPE);
+						np = sh_fsearch(name,NV_ADD|NV_NOSCOPE);
 					else
 #endif /* SHOPT_NAMESPACE */
 					np = nv_open(name,sh_subfuntree(1),NV_NOARRAY|NV_IDENT|NV_NOSCOPE);
@@ -714,7 +714,7 @@ static int     setall(char **argv,register int flag,Dt_t *troot,struct tdata *tp
 #if SHOPT_NAMESPACE
 					np = 0;
 					if(sh.namespace)
-						np = sh_fsearch(name,HASH_NOSCOPE);
+						np = sh_fsearch(name,NV_NOSCOPE);
 					if(!np)
 #endif /* SHOPT_NAMESPACE */
 					{
@@ -761,7 +761,7 @@ static int     setall(char **argv,register int flag,Dt_t *troot,struct tdata *tp
 			/* tracked alias */
 			if(troot==sh.track_tree && tp->aflag=='-')
 			{
-				np = nv_search(name,troot,NV_ADD|HASH_NOSCOPE);
+				np = nv_search(name,troot,NV_ADD|NV_NOSCOPE);
 				path_alias(np,path_absolute(nv_name(np),NIL(Pathcomp_t*),0));
 				continue;
 			}
@@ -1349,7 +1349,7 @@ static int unall(int argc, char **argv, register Dt_t *troot)
 		{
 #if SHOPT_NAMESPACE
 			if(sh.namespace && troot!=sh.var_tree)
-				np = sh_fsearch(name,nflag?HASH_NOSCOPE:0);
+				np = sh_fsearch(name,nflag);
 			if(!np)
 #endif /* SHOPT_NAMESPACE */
 			np=nv_open(name,troot,NV_NOADD|nflag);

src/cmd/ksh93/edit/completion.c

@@ -580,7 +580,7 @@ int ed_macro(Edit_t *ep, register int i)
 		ep->e_macro[2] = ed_getchar(ep,1);
 	else
 		ep->e_macro[2] = 0;
-	if (isalnum(i)&&(np=nv_search(ep->e_macro,sh.alias_tree,HASH_SCOPE))&&(out=nv_getval(np)))
+	if (isalnum(i)&&(np=nv_search(ep->e_macro,sh.alias_tree,0))&&(out=nv_getval(np)))
 	{
 #if SHOPT_MULTIBYTE
 		/* copy to buff in internal representation */

src/cmd/ksh93/include/name.h

@@ -126,7 +126,6 @@ struct Ufunction
 #define NV_TYPE		0x1000000
 #define NV_STATIC	0x2000000
 #define NV_COMVAR	0x4000000
-#define NV_UNATTR	0x800000		/* unset attributes before assignment */
 #define NV_FUNCTION	(NV_RJUST|NV_FUNCT)	/* value is shell function */
 #define NV_FPOSIX	NV_LJUST		/* POSIX function semantics */
 #define NV_FTMP		NV_ZFILL		/* function source in tmpfile */

src/cmd/ksh93/include/nval.h

@@ -32,7 +32,6 @@
 #include	<ast.h>
 #include	<cdt.h>
 #include	<option.h>
-#include	<hash.h>
 
 typedef struct Namval Namval_t;
 typedef struct Namfun Namfun_t;
@@ -174,7 +173,6 @@ struct Namval
 #define NV_ADD		8
 					/* add node if not found */
 #define NV_ASSIGN	NV_NOFREE	/* assignment is possible */
-#define NV_NOASSIGN	0		/* backward compatibility */
 #define NV_NOARRAY	0x200000	/* array name not possible */
 #define NV_IARRAY	0x400000	/* for indexed array */
 #define NV_NOREF	NV_REF		/* don't follow reference */
@@ -184,6 +182,7 @@ struct Namval
 #define NV_NOSCOPE	0x80000		/* look only in current scope */
 #define NV_NOFAIL	0x100000	/* return 0 on failure, no msg */
 #define NV_NODISC	NV_IDENT	/* ignore disciplines */
+#define NV_UNATTR	0x800000	/* unset attributes before assignment */
 #define NV_GLOBAL	0x20000000	/* create global variable, ignoring local scope */
 
 #define NV_FUNCT	NV_IDENT	/* option for nv_create */

src/cmd/ksh93/include/shell.h

@@ -28,7 +28,7 @@
  *
  */
 
-#define SH_VERSION	20220106
+#define SH_VERSION	20220719
 
 #include	<ast.h>
 #include	<cdt.h>

src/cmd/ksh93/sh/args.c

@@ -141,7 +141,7 @@ int sh_argopts(int argc,register char *argv[])
 		switch(n)
 		{
 	 	    case 'A':
-			np = nv_open(opt_info.arg,sh.var_tree,NV_NOASSIGN|NV_ARRAY|NV_VARNAME);
+			np = nv_open(opt_info.arg,sh.var_tree,NV_ARRAY|NV_VARNAME);
 			if(f)
 				nv_unset(np);
 			continue;

src/cmd/ksh93/sh/arith.c

@@ -67,7 +67,7 @@ static Namval_t *scope(register Namval_t *np,register struct lval *lvalue,int as
 	Dt_t	*sdict = (sh.st.real_fun? sh.st.real_fun->sdict:0);
 	Dt_t	*nsdict = (sh.namespace?nv_dict(sh.namespace):0);
 	Dt_t	*root = sh.var_tree;
-	assign = assign?NV_ASSIGN:NV_NOASSIGN;
+	assign = assign?NV_ASSIGN:0;
 	lvalue->nosub = 0;
 	if(nosub<0 && lvalue->ovalue)
 		return((Namval_t*)lvalue->ovalue);
@@ -101,9 +101,9 @@ static Namval_t *scope(register Namval_t *np,register struct lval *lvalue,int as
 	}
 	if((lvalue->emode & ARITH_COMP) && dtvnext(root))
 	{
-		if(mp = nv_search(cp, sdict ? sdict : root, HASH_NOSCOPE|HASH_SCOPE|HASH_BUCKET))
+		if(mp = nv_search(cp, sdict ? sdict : root, NV_NOSCOPE|NV_REF))
 			np = mp;
-		else if(nsdict && (mp = nv_search(cp, nsdict, HASH_SCOPE|HASH_BUCKET)))
+		else if(nsdict && (mp = nv_search(cp, nsdict, NV_REF)))
 			np = mp;
 	}
 	while(nv_isref(np))
@@ -365,7 +365,7 @@ static Sfdouble_t arith(const char **ptr, struct lval *lvalue, int type, Sfdoubl
 					np = &NaNnod;
 					nv_onattr(np,NV_NOFREE|NV_LDOUBLE|NV_RDONLY);
 				}
-				else if(!(np = nv_open(*ptr,root,NV_NOREF|NV_NOASSIGN|NV_VARNAME|dot)))
+				else if(!(np = nv_open(*ptr,root,NV_NOREF|NV_VARNAME|dot)))
 				{
 					lvalue->value = (char*)*ptr;
 					lvalue->flag =  str-lvalue->value;

src/cmd/ksh93/sh/array.c

@@ -1744,9 +1744,9 @@ void *nv_associative(register Namval_t *np,const char *sp,int mode)
 				return(0);
 			type = nv_isattr(np,NV_PUBLIC&~(NV_ARRAY|NV_CHILD|NV_MINIMAL));
 			if(mode)
-				mode = NV_ADD|HASH_NOSCOPE;
+				mode = NV_ADD|NV_NOSCOPE;
 			else if(ap->header.nelem&ARRAY_NOSCOPE)
-				mode = HASH_NOSCOPE;
+				mode = NV_NOSCOPE;
 			if(*sp==0 && sh_isoption(SH_XTRACE) && (mode&NV_ADD))
 				errormsg(SH_DICT,ERROR_warn(0),"adding empty subscript"); 
 			if(sh.subshell && (mp=nv_search(sp,ap->header.table,0)) && nv_isnull(mp))
@@ -1781,7 +1781,7 @@ void *nv_associative(register Namval_t *np,const char *sp,int mode)
 				ap->nextpos = (Namval_t*)dtnext(ap->header.table,mp);
 			}
 			else if(!mp && *sp && mode==0)
-				mp = nv_search(sp,ap->header.table,NV_ADD|HASH_NOSCOPE);
+				mp = nv_search(sp,ap->header.table,NV_ADD|NV_NOSCOPE);
 			np = mp;
 			if(ap->pos && ap->pos==np)
 				ap->header.nelem |= ARRAY_SCAN;

src/cmd/ksh93/sh/io.c

@@ -1183,7 +1183,7 @@ int	sh_redirect(struct ionod *iop, int flag)
 		np = 0;
 		if(iop->iovname)
 		{
-			np = nv_open(iop->iovname,sh.var_tree,NV_NOASSIGN|NV_VARNAME);
+			np = nv_open(iop->iovname,sh.var_tree,NV_VARNAME);
 			if(nv_isattr(np,NV_RDONLY))
 			{
 				errormsg(SH_DICT,ERROR_exit(1),e_readonly, nv_name(np));

src/cmd/ksh93/sh/lex.c

@@ -1490,7 +1490,7 @@ int sh_lex(Lex_t* lp)
 			/* check for aliases */
 			Namval_t* np;
 			if(!lp->lex.incase && !assignment && fcpeek(0)!=LPAREN &&
-				(np=nv_search(state,sh.alias_tree,HASH_SCOPE))
+				(np=nv_search(state,sh.alias_tree,0))
 				&& !nv_isattr(np,NV_NOEXPAND)
 				&& (lp->aliasok!=2 || nv_isattr(np,BLT_DCL))
 				&& (!sh_isstate(SH_NOALIAS) || nv_isattr(np,NV_NOFREE))

src/cmd/ksh93/sh/macro.c

@@ -1317,7 +1317,7 @@ static int varsub(Mac_t *mp)
 			}
 			goto nosub;
 		}
-		flag |= NV_NOASSIGN|NV_VARNAME|NV_NOADD;
+		flag |= NV_VARNAME|NV_NOADD;
 		if(c=='=' || c=='?' || (c==':' && ((d=fcpeek(0))=='=' || d=='?')))
 		{
 			if(c=='=' || (c==':' && d=='='))

src/cmd/ksh93/sh/name.c

@@ -575,7 +575,7 @@ void nv_setlist(register struct argnod *arg,register int flags, Namval_t *typ)
 			*eqp = '\0';
 			if((np = nv_search(cp,dtvnext(vartree),0)) && np->nvflag)
 			{
-				mp = nv_search(cp,vartree,NV_ADD|HASH_NOSCOPE);
+				mp = nv_search(cp,vartree,NV_ADD|NV_NOSCOPE);
 				mp->nvname = np->nvname;  /* put_lang() (init.c) compares nvname pointers */
 				mp->nvflag = np->nvflag;
 				mp->nvsize = np->nvsize;
@@ -785,7 +785,7 @@ Namval_t *nv_create(const char *name,  Dt_t *root, int flags, Namfun_t *dp)
 			dp->last = cp;
 			mode =  (c=='.' || (flags&NV_NOADD))?add:NV_ADD;
 			if(level++ || ((flags&NV_NOSCOPE) && c!='.'))
-				mode |= HASH_NOSCOPE;
+				mode |= NV_NOSCOPE;
 			np=0;
 			if(top)
 			{
@@ -806,7 +806,7 @@ Namval_t *nv_create(const char *name,  Dt_t *root, int flags, Namfun_t *dp)
 #endif /* SHOPT_NAMESPACE */
 					{
 #if SHOPT_NAMESPACE
-						if(!(nq = nv_search((char*)np,sh.var_base,HASH_BUCKET)))
+						if(!(nq = nv_search((char*)np,sh.var_base,NV_REF)))
 #endif /* SHOPT_NAMESPACE */
 						nq = np;
 						sh.last_root = sh.var_tree->walk;
@@ -839,7 +839,7 @@ Namval_t *nv_create(const char *name,  Dt_t *root, int flags, Namfun_t *dp)
 						np = 0;
 					}
 					if(!np || sh.var_tree->walk!=root)
-						np =  nv_search(name,root,HASH_NOSCOPE|NV_ADD);
+						np =  nv_search(name,root,NV_NOSCOPE|NV_ADD);
 				}
 			}
 #if SHOPT_NAMESPACE
@@ -1026,7 +1026,7 @@ Namval_t *nv_create(const char *name,  Dt_t *root, int flags, Namfun_t *dp)
 				{
 					int n = 0;
 					sub = 0;
-					mode &= ~HASH_NOSCOPE;
+					mode &= ~NV_NOSCOPE;
 					if(c=='[')
 					{
 #if SHOPT_FIXEDARRAY
@@ -1343,7 +1343,7 @@ Namval_t *nv_open(const char *name, Dt_t *root, int flags)
 	{
 		long mode = ((flags&NV_NOADD)?0:NV_ADD);
 		if(flags&NV_NOSCOPE)
-			mode |= HASH_SCOPE|HASH_NOSCOPE;
+			mode |= NV_NOSCOPE;
 		np = nv_search(name,root,mode);
 		if(np && !(flags&NV_REF))
 		{
@@ -1443,7 +1443,7 @@ Namval_t *nv_open(const char *name, Dt_t *root, int flags)
 #endif
 	if(fname)
 	{
-		c = ((flags&NV_NOSCOPE)?HASH_NOSCOPE:0)|((flags&NV_NOADD)?0:NV_ADD);
+		c = (flags&NV_NOSCOPE)|((flags&NV_NOADD)?0:NV_ADD);
 		*fname = '.';
 		np = nv_search(name, funroot, c);
 		*fname = 0;
@@ -1510,7 +1510,7 @@ Namval_t *nv_open(const char *name, Dt_t *root, int flags)
 				{
 					if(mp=nv_opensub(np))
 						np = mp;
-					else if(!array_assoc(ap) && (mp = nv_open(cp,sh.var_tree,NV_NOFAIL|NV_VARNAME|NV_NOARRAY|NV_NOASSIGN|NV_NOADD)) && nv_isvtree(np))
+					else if(!array_assoc(ap) && (mp = nv_open(cp,sh.var_tree,NV_NOFAIL|NV_VARNAME|NV_NOARRAY|NV_NOADD)) && nv_isvtree(np))
 					{
 						ap->nelem |= ARRAY_TREE;
 						nv_putsub(np,(char*)0,ARRAY_ADD|nv_aindex(np));
@@ -1524,7 +1524,7 @@ Namval_t *nv_open(const char *name, Dt_t *root, int flags)
 			nv_putval(np, cp, c);
 			if(isref)
 			{
-				if(nv_search((char*)np,sh.var_base,HASH_BUCKET))
+				if(nv_search((char*)np,sh.var_base,NV_REF))
 					sh.last_root = sh.var_base;
 				nv_setref(np,(Dt_t*)0,NV_VARNAME);
 			}
@@ -2260,7 +2260,7 @@ void nv_rehash(register Namval_t *np,void *data)
 	if(sh.subshell)
 	{
 		/* invalidate subshell node; if none exists, add a dummy */
-		np = nv_search(nv_name(np),sh.track_tree,NV_ADD|HASH_NOSCOPE);
+		np = nv_search(nv_name(np),sh.track_tree,NV_ADD|NV_NOSCOPE);
 	}
 	nv_onattr(np,NV_NOALIAS);
 }
@@ -3369,7 +3369,7 @@ void nv_setref(register Namval_t *np, Dt_t *hp, int flags)
 			UNREACHABLE();
 		}
 		/* bind to earlier scope, or add to global scope */
-		if(!(hp=dtvnext(hp)) || (nq=nv_search((char*)np,hp,NV_ADD|HASH_BUCKET))==np)
+		if(!(hp=dtvnext(hp)) || (nq=nv_search((char*)np,hp,NV_ADD|NV_REF))==np)
 		{
 			errormsg(SH_DICT,ERROR_exit(1),e_selfref,nv_name(np));
 			UNREACHABLE();

src/cmd/ksh93/sh/nvdisc.c

@@ -941,13 +941,24 @@ int nv_clone(Namval_t *np, Namval_t *mp, int flags)
 	return(1);
 }
 
+/*
+ * Low-level function to look up <name> in <root>. Returns a pointer to the
+ * name-value node found, or NULL if not found. <mode> is an options bitmask:
+ * - If NV_NOSCOPE is set, the search is only done in <root> itself and
+ *   not in any trees it has a view to (i.e. is connected to through scoping).
+ * - If NV_ADD is set and <name> is not fond, a node by that name is created
+ *   in <root> and a pointer to the newly created node is returned.
+ * - If NV_REF is set, <name> is a pointer to a name-value node, and that
+ *   node's name is used.
+ * Note: The mode bitmask is NOT compatible with nv_open's flags bitmask.
+ */
 Namval_t *nv_search(const char *name, Dt_t *root, int mode)
 {
 	register Namval_t *np;
 	register Dt_t *dp = 0;
-	if(mode&HASH_NOSCOPE)
+	if(mode&NV_NOSCOPE)
 		dp = dtview(root,0);
-	if(mode&HASH_BUCKET)
+	if(mode&NV_REF)
 	{
 		Namval_t *mp = (void*)name;
 		if(!(np = dtsearch(root,mp)) && (mode&NV_ADD))
@@ -961,9 +972,9 @@ Namval_t *nv_search(const char *name, Dt_t *root, int mode)
 	}
 	if(!np && (mode&NV_ADD))
 	{
-		if(sh.namespace && !(mode&HASH_NOSCOPE) && root==sh.var_tree)
+		if(sh.namespace && !(mode&NV_NOSCOPE) && root==sh.var_tree)
 			root = nv_dict(sh.namespace);
-		else if(!dp && !(mode&HASH_NOSCOPE))
+		else if(!dp && !(mode&NV_NOSCOPE))
 		{
 			register Dt_t *next;
 			while(next=dtvnext(root))
@@ -1025,7 +1036,7 @@ Namval_t *nv_bfsearch(const char *name, Dt_t *root, Namval_t **var, char **last)
 		*last = cp;
 	c = *cp;
 	*cp = 0;
-	nq=nv_open(stakptr(offset),0,NV_VARNAME|NV_NOASSIGN|NV_NOADD|NV_NOFAIL);
+	nq=nv_open(stakptr(offset),0,NV_VARNAME|NV_NOADD|NV_NOFAIL);
 	*cp = c;
 	if(!nq)
 	{