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git://git.code.sf.net/p/cdesktopenv/code
synced 2025-02-15 04:32:24 +00:00
libast: Update cdt(3): Allow empty strings in (dt)trees
This backports most of the Cdt (container data types) mechanism from the ksh 93v- beta, based on ground work done by OpenSUSE: https://build.opensuse.org/package/view_file/shells/ksh/ksh93-dttree-crash.dif plus adaptations to match ksh 93u+m and an updated manual page (src/lib/libast/man/cdt.3) added directly from the 93v- sources. | Thu Dec 20 12:48:02 UTC 2012 - werner@suse.de | | - Add ksh93-dttree-crash.dif - Allow empty strings in (dt)trees | (bnc#795324) | | Fri Oct 25 14:07:57 UTC 2013 - werner@suse.de | | - Rework patch ksh93-dttree-crash.dif As usual, precious little information is available because the OpenSUSE bug report is currently closed to the public: https://bugzilla.opensuse.org/show_bug.cgi?id=795324 However, a cursory inspection suggests that this code contains improvements to do with concurrent processing and related robustness. The new cdt.3 manual page adds a lot about that. This has been in production use on OpenSUSE for a long time, so hopefully this will make ksh a little more stable again. Only one way to find out: let's commit and test this... BTW, to get a nice manual, use groff and ghostscript's ps2pdf: $ groff -tman src/lib/libast/man/cdt.3 | ps2pdf - cdt.3.pdf
This commit is contained in:
Martijn Dekker
parent
aa2644ab84
commit
cc4927529b
21 changed files with 708 additions and 210 deletions
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@ -184,7 +184,10 @@ static Namval_t *scope(register Namval_t *np,register struct lval *lvalue,int as
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{
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ap = nv_arrayptr(np);
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if(ap && !ap->table)
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{
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ap->table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->table,shp,1);
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}
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if(ap && ap->table && (nq=nv_search(nv_getsub(np),ap->table,NV_ADD)))
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nq->nvenv = (char*)np;
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if(nq && nv_isnull(nq))
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@ -95,6 +95,7 @@ static Namarr_t *array_scope(Namval_t *np, Namarr_t *ap, int flags)
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if(is_associative(aq))
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{
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aq->scope = (void*)dtopen(&_Nvdisc,Dtoset);
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dtuserdata(aq->scope,&sh,1);
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dtview((Dt_t*)aq->scope,aq->table);
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aq->table = (Dt_t*)aq->scope;
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return(aq);
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@ -373,7 +374,10 @@ static Namval_t *array_find(Namval_t *np,Namarr_t *arp, int flag)
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{
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char *cp;
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if(!ap->header.table)
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{
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ap->header.table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->header.table,&sh,1);
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}
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sfprintf(sh.strbuf,"%d",ap->cur);
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cp = sfstruse(sh.strbuf);
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mp = nv_search(cp, ap->header.table, NV_ADD);
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@ -410,7 +414,10 @@ int nv_arraysettype(Namval_t *np, Namval_t *tp, const char *sub, int flags)
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av[1] = 0;
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sh.last_table = 0;
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if(!ap->table)
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{
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ap->table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->table,&sh,1);
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}
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if(nq = nv_search(sub, ap->table, NV_ADD))
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{
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if(!nq->nvfun && nq->nvalue.cp && *nq->nvalue.cp==0)
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@ -452,7 +459,6 @@ static Namfun_t *array_clone(Namval_t *np, Namval_t *mp, int flags, Namfun_t *fp
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int nelem, skipped=0;
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Dt_t *otable=ap->table;
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struct index_array *aq = (struct index_array*)ap, *ar;
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Shell_t *shp = sh_getinterp();
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if(flags&NV_MOVE)
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{
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if((flags&NV_COMVAR) && nv_putsub(np,NIL(char*),ARRAY_SCAN))
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@ -485,6 +491,7 @@ static Namfun_t *array_clone(Namval_t *np, Namval_t *mp, int flags, Namfun_t *fp
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if(ap->table)
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{
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ap->table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->table,&sh,1);
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if(ap->scope && !(flags&NV_COMVAR))
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{
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ap->scope = ap->table;
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@ -855,6 +862,7 @@ static struct index_array *array_grow(Namval_t *np, register struct index_array
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if(nv_hasdisc(np,&array_disc) || (nv_type(np) && nv_isvtree(np)))
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{
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ap->header.table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->header.table,&sh,1);
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mp = nv_search("0", ap->header.table,NV_ADD);
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if(mp && nv_isnull(mp))
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{
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@ -1180,7 +1188,6 @@ Namval_t *nv_putsub(Namval_t *np,register char *sp,register long mode)
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{
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if(sp)
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{
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Shell_t *shp = sh_getinterp();
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if(ap && ap->xp && !strmatch(sp,"+([0-9])"))
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{
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Namval_t *mp = nv_namptr(ap->xp,0);
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@ -1188,7 +1195,7 @@ Namval_t *nv_putsub(Namval_t *np,register char *sp,register long mode)
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size = nv_getnum(mp);
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}
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else
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size = (int)sh_arith(shp,(char*)sp);
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size = (int)sh_arith(&sh,(char*)sp);
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}
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if(size <0 && ap)
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size += array_maxindex(np);
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@ -1242,7 +1249,10 @@ Namval_t *nv_putsub(Namval_t *np,register char *sp,register long mode)
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char *cp;
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Namval_t *mp;
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if(!ap->header.table)
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{
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ap->header.table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->header.table,&sh,1);
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}
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sfprintf(sh.strbuf,"%d",ap->cur);
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cp = sfstruse(sh.strbuf);
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mp = nv_search(cp, ap->header.table, NV_ADD);
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@ -1379,7 +1389,6 @@ static void array_fixed_setdata(Namval_t *np,Namarr_t* ap,struct fixed_array* fp
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static int array_fixed_init(Namval_t *np, char *sub, char *cp)
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{
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Shell_t *shp=sh_getinterp();
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Namarr_t *ap;
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struct fixed_array *fp;
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int n=1,sz;
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@ -1403,12 +1412,12 @@ static int array_fixed_init(Namval_t *np, char *sub, char *cp)
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fp->max = (int*)(fp+1);
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fp->incr = fp->max+n;
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fp->cur = fp->incr+n;
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fp->max[0] = (int)sh_arith(shp,(char*)sub);
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fp->max[0] = (int)sh_arith(&sh,(char*)sub);
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for(n=1,ep=cp;*ep=='['; ep=cp)
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{
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cp = nv_endsubscript(np,ep,0);
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cp[-1]=0;
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fp->max[n++] = sz = (int)sh_arith(shp,(char*)ep+1);
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fp->max[n++] = sz = (int)sh_arith(&sh,(char*)ep+1);
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if(sz<0)
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{
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free((void*)ap);
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@ -1429,7 +1438,6 @@ static int array_fixed_init(Namval_t *np, char *sub, char *cp)
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static char *array_fixed(Namval_t *np, char *sub, char *cp,int mode)
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{
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Shell_t *shp=sh_getinterp();
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Namarr_t *ap = nv_arrayptr(np);
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struct fixed_array *fp = (struct fixed_array*)ap->fixed;
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char *ep;
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@ -1447,7 +1455,7 @@ static char *array_fixed(Namval_t *np, char *sub, char *cp,int mode)
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}
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else
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fp->curi = 0;
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size = (int)sh_arith(shp,(char*)sub);
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size = (int)sh_arith(&sh,(char*)sub);
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fp->cur[n] = size;
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if(size >= fp->max[n] || (size < 0))
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errormsg(SH_DICT,ERROR_exit(1),e_subscript, nv_name(np));
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@ -1459,7 +1467,7 @@ static char *array_fixed(Namval_t *np, char *sub, char *cp,int mode)
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errormsg(SH_DICT,ERROR_exit(1),e_subscript, nv_name(np));
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cp = nv_endsubscript(np,ep,0);
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cp[-1]=0;
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size = (int)sh_arith(shp,(char*)ep+1);
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size = (int)sh_arith(&sh,(char*)ep+1);
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if(size >= fp->max[n] || (size < 0))
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errormsg(SH_DICT,ERROR_exit(1),e_subscript, nv_name(np));
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fp->cur[n] = size;
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@ -1658,6 +1666,7 @@ void *nv_associative(register Namval_t *np,const char *sp,int mode)
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if(ap = (struct assoc_array*)calloc(1,sizeof(struct assoc_array)))
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{
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ap->header.table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->header.table,&sh,1);
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ap->cur = 0;
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ap->pos = 0;
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ap->header.hdr.disc = &array_disc;
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@ -1730,8 +1739,7 @@ void *nv_associative(register Namval_t *np,const char *sp,int mode)
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case NV_ANAME:
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if(ap->cur)
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{
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Shell_t *shp = sh_getinterp();
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if(!shp->instance && nv_isnull(ap->cur))
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if(!sh.instance && nv_isnull(ap->cur))
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return(NIL(void*));
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return((void*)ap->cur->nvname);
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}
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@ -1812,9 +1812,13 @@ static Init_t *nv_init(Shell_t *shp)
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(OPTINDNOD)->nvalue.lp = (&shp->st.optindex);
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/* set up the seconds clock */
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shp->alias_tree = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(shp->alias_tree,shp,1);
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shp->track_tree = dtopen(&_Nvdisc,Dtset);
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dtuserdata(shp->track_tree,shp,1);
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shp->bltin_tree = sh_inittree(shp,(const struct shtable2*)shtab_builtins);
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dtuserdata(shp->bltin_tree,shp,1);
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shp->fun_tree = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(shp->fun_tree,shp,1);
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dtview(shp->fun_tree,shp->bltin_tree);
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nv_mount(DOTSHNOD, "type", shp->typedict=dtopen(&_Nvdisc,Dtoset));
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nv_adddisc(DOTSHNOD, shdiscnames, (Namval_t**)0);
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@ -1857,6 +1861,7 @@ Dt_t *sh_inittree(Shell_t *shp,const struct shtable2 *name_vals)
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nbltins = n;
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}
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base_treep = treep = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(treep,shp,1);
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treep->user = (void*)shp;
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for(tp=name_vals;*tp->sh_name;tp++,np++)
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{
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@ -2738,7 +2738,10 @@ static char *sh_tilde(Shell_t *shp,register const char *string)
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skip:
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#endif /* _WINIX */
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if(!logins_tree)
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{
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logins_tree = dtopen(&_Nvdisc,Dtbag);
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dtuserdata(logins_tree,shp,1);
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}
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if(np=nv_search(string,logins_tree,NV_ADD))
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{
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save = shp->subshell;
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@ -181,6 +181,7 @@ int sh_main(int ac, char *av[], Shinit_f userinit)
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/* preset aliases for interactive non-POSIX ksh */
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dtclose(shp->alias_tree);
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shp->alias_tree = sh_inittree(shp,shtab_aliases);
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dtuserdata(shp->alias_tree,shp,1);
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}
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}
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#if SHOPT_REMOTE
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@ -789,6 +789,7 @@ Namval_t *nv_create(const char *name, Dt_t *root, int flags, Namfun_t *dp)
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{
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Dt_t *dp = dtview(shp->var_tree,(Dt_t*)0);
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rp->sdict = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(rp->sdict,shp,1);
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dtview(rp->sdict,dp);
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dtview(shp->var_tree,rp->sdict);
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}
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@ -1131,7 +1132,10 @@ Namval_t *nv_create(const char *name, Dt_t *root, int flags, Namfun_t *dp)
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ap = nv_arrayptr(np);
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}
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if(n && ap && !ap->table)
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{
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ap->table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->table,shp,1);
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}
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if(ap && ap->table && (nq=nv_search(sub,ap->table,n)))
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nq->nvenv = (char*)np;
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if(nq && nv_isnull(nq))
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@ -2285,6 +2289,7 @@ void sh_scope(Shell_t *shp, struct argnod *envlist, int fun)
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newroot = nv_dict(shp->namespace);
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#endif /* SHOPT_NAMESPACE */
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newscope = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(newscope,shp,1);
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if(envlist)
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{
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dtview(newscope,(Dt_t*)shp->var_tree);
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@ -3277,7 +3282,10 @@ int nv_rename(register Namval_t *np, int flags)
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if(ap=nv_arrayptr(np))
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{
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if(!ap->table)
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{
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ap->table = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(ap->table,shp,1);
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}
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if(ap->table)
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mp = nv_search(nv_getsub(np),ap->table,NV_ADD);
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nv_arraychild(np,mp,0);
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@ -1299,6 +1299,7 @@ static Namfun_t *clone_table(Namval_t* np, Namval_t *mp, int flags, Namfun_t *fp
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Dt_t *oroot=tp->dict,*nroot=dtopen(&_Nvdisc,Dtoset);
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if(!nroot)
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return(0);
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dtuserdata(nroot,dtuserdata(oroot,0,0),1);
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memcpy((void*)ntp,(void*)fp,sizeof(struct table));
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ntp->dict = nroot;
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ntp->parent = nv_lastdict();
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@ -404,6 +404,7 @@ Dt_t *sh_subtracktree(int create)
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if(create && sh.subshell && !sh.subshare && sp && !sp->strack)
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{
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sp->strack = dtopen(&_Nvdisc,Dtset);
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dtuserdata(sp->strack,&sh,1);
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dtview(sp->strack,sh.track_tree);
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sh.track_tree = sp->strack;
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}
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@ -420,6 +421,7 @@ Dt_t *sh_subfuntree(int create)
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if(create && sh.subshell && !sh.subshare && sp && !sp->sfun)
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{
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sp->sfun = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(sp->sfun,&sh,1);
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dtview(sp->sfun,sh.fun_tree);
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sh.fun_tree = sp->sfun;
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}
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@ -2429,6 +2429,7 @@ int sh_exec(register const Shnode_t *t, int flags)
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else
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{
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root = dtopen(&_Nvdisc,Dtoset);
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dtuserdata(root,shp,1);
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nv_mount(np, (char*)0, root);
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np->nvalue.cp = Empty;
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dtview(root,shp->var_base);
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@ -2484,11 +2485,6 @@ int sh_exec(register const Shnode_t *t, int flags)
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slp = (struct slnod*)np->nvenv;
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sh_funstaks(slp->slchild,-1);
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stakdelete(slp->slptr);
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if(shp->funload)
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{
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free((void*)np->nvalue.rp);
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np->nvalue.rp = 0;
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}
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if(rp->sdict)
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{
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Namval_t *mp, *nq;
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@ -2502,6 +2498,12 @@ int sh_exec(register const Shnode_t *t, int flags)
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dtclose(rp->sdict);
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rp->sdict = 0;
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}
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if(shp->funload)
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{
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if(!shp->fpathdict)
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free((void*)np->nvalue.rp);
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np->nvalue.rp = 0;
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}
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}
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if(!np->nvalue.rp)
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{
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@ -2540,7 +2542,10 @@ int sh_exec(register const Shnode_t *t, int flags)
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if(!shp->fpathdict)
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shp->fpathdict = dtopen(&_Rpdisc,Dtobag);
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if(shp->fpathdict)
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{
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dtuserdata(shp->fpathdict,shp,1);
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dtinsert(shp->fpathdict,rp);
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}
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}
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}
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else
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@ -3964,6 +3964,14 @@ make install
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prev cdt/dtopen.c
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exec - ${CC} ${mam_cc_FLAGS} ${KSH_RELFLAGS} ${CCFLAGS} -I. -Icdt -Icomp -Iinclude -Istd -I${INSTALLROOT}/include/ast -D_PACKAGE_ast -c cdt/dtopen.c
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done dtopen.o generated
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make dtstat.o
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make cdt/dtstat.c
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prev cdt/dthdr.h implicit
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done cdt/dtstat.c
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meta dtstat.o %.c>%.o cdt/dtstat.c dtstat
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prev cdt/dtstat.c
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exec - ${CC} ${mam_cc_FLAGS} ${KSH_RELFLAGS} ${CCFLAGS} -I. -Icdt -Icomp -Iinclude -Istd -I${INSTALLROOT}/include/ast -D_PACKAGE_ast -c cdt/dtstat.c
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done dtstat.o generated
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make dtstrhash.o
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make cdt/dtstrhash.c
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prev cdt/dthdr.h implicit
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@ -3980,6 +3988,14 @@ make install
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prev cdt/dttree.c
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exec - ${CC} ${mam_cc_FLAGS} ${KSH_RELFLAGS} ${CCFLAGS} -I. -Icdt -Icomp -Iinclude -Istd -I${INSTALLROOT}/include/ast -D_PACKAGE_ast -c cdt/dttree.c
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done dttree.o generated
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make dtuser.o
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make cdt/dtuser.c
|
||||
prev cdt/dthdr.h implicit
|
||||
done cdt/dtuser.c
|
||||
meta dtuser.o %.c>%.o cdt/dtuser.c dtuser
|
||||
prev cdt/dtuser.c
|
||||
exec - ${CC} ${mam_cc_FLAGS} ${KSH_RELFLAGS} ${CCFLAGS} -I. -Icdt -Icomp -Iinclude -Istd -I${INSTALLROOT}/include/ast -D_PACKAGE_ast -c cdt/dtuser.c
|
||||
done dtuser.o generated
|
||||
make dtview.o
|
||||
make cdt/dtview.c
|
||||
prev cdt/dthdr.h implicit
|
||||
|
|
@ -6095,7 +6111,7 @@ make install
|
|||
exec - ${AR} rc libast.a streval.o strexpr.o strmatch.o strcopy.o modei.o modex.o strmode.o strlcat.o strlcpy.o strlook.o strncopy.o strsearch.o strpsearch.o stresc.o stropt.o strtape.o strpcmp.o strnpcmp.o strvcmp.o strnvcmp.o tok.o tokline.o tokscan.o pathaccess.o pathcat.o pathcanon.o pathcheck.o pathpath.o pathexists.o pathfind.o pathkey.o pathprobe.o pathrepl.o pathnative.o pathposix.o pathtemp.o pathtmp.o pathstat.o pathgetlink.o pathsetlink.o pathbin.o pathshell.o pathcd.o pathprog.o ftwalk.o ftwflags.o fts.o astintercept.o conformance.o getenv.o setenviron.o optget.o optjoin.o optesc.o optctx.o strsort.o struniq.o magic.o mime.o mimetype.o signal.o sigflag.o systrace.o error.o errorf.o errormsg.o errorx.o localeconv.o setlocale.o translate.o catopen.o iconv.o lc.o lctab.o mc.o base64.o recfmt.o recstr.o reclen.o fmtrec.o fmtbase.o fmtbuf.o fmtclock.o fmtdev.o fmtelapsed.o fmterror.o fmtesc.o fmtfmt.o fmtfs.o fmtident.o fmtint.o fmtip4.o fmtip6.o fmtls.o fmtmatch.o fmtmode.o fmtnum.o fmtperm.o fmtre.o fmttime.o
|
||||
exec - ${AR} rc libast.a fmtuid.o fmtgid.o fmtsignal.o fmtscale.o fmttmx.o fmttv.o fmtversion.o strelapsed.o strperm.o struid.o strgid.o strtoip4.o strtoip6.o stack.o stk.o swapget.o swapmem.o swapop.o swapput.o sigdata.o sigcrit.o sigunblock.o procopen.o procclose.o procrun.o procfree.o tmdate.o tmequiv.o tmfix.o tmfmt.o tmform.o tmgoff.o tminit.o tmleap.o tmlex.o tmlocale.o tmmake.o tmpoff.o tmscan.o tmsleep.o tmtime.o tmtype.o tmweek.o tmword.o tmzone.o tmxdate.o tmxduration.o tmxfmt.o tmxgettime.o tmxleap.o tmxmake.o tmxscan.o tmxsettime.o tmxsleep.o tmxtime.o tmxtouch.o tvcmp.o tvgettime.o tvsettime.o tvsleep.o tvtouch.o cmdarg.o vecargs.o vecfile.o vecfree.o vecload.o vecstring.o univdata.o touch.o mnt.o debug.o memccpy.o memchr.o memcmp.o memcpy.o memdup.o memmove.o memset.o mkdir.o mkfifo.o mknod.o rmdir.o remove.o rename.o link.o unlink.o strdup.o strchr.o strrchr.o strstr.o strtod.o strtold.o strtol.o strtoll.o strtoul.o strtoull.o strton.o strtonll.o strntod.o strntold.o strnton.o
|
||||
exec - ${AR} rc libast.a strntonll.o strntol.o strntoll.o strntoul.o strntoull.o strcasecmp.o strncasecmp.o strerror.o mktemp.o tmpnam.o fsync.o execlp.o execve.o execvp.o execvpe.o spawnveg.o vfork.o killpg.o hsearch.o tsearch.o getlogin.o putenv.o setenv.o unsetenv.o lstat.o statvfs.o eaccess.o gross.o omitted.o readlink.o symlink.o getpgrp.o setpgid.o setsid.o waitpid.o creat64.o fcntl.o open.o atexit.o getdents.o getwd.o dup2.o errno.o getpreroot.o ispreroot.o realopen.o setpreroot.o getgroups.o mount.o system.o iblocks.o modedata.o tmdata.o memfatal.o sfkeyprintf.o sfdcdio.o sfdcdos.o sfdcfilter.o sfdcseekable.o sfdcslow.o sfdcsubstr.o sfdctee.o sfdcunion.o sfdcmore.o sfdcprefix.o wc.o wc2utf8.o basename.o closelog.o dirname.o fmtmsglib.o fnmatch.o ftw.o getdate.o getsubopt.o glob.o nftw.o openlog.o re_comp.o resolvepath.o realpath.o regcmp.o regexp.o setlogmask.o strftime.o strptime.o swab.o syslog.o tempnam.o wordexp.o mktime.o regalloc.o regclass.o regcoll.o regcomp.o regcache.o regdecomp.o regerror.o regexec.o regfatal.o reginit.o
|
||||
exec - ${AR} rc libast.a regnexec.o regsubcomp.o regsubexec.o regsub.o regrecord.o regrexec.o regstat.o dtclose.o dtdisc.o dthash.o dtlist.o dtmethod.o dtopen.o dtstrhash.o dttree.o dtview.o dtwalk.o dtnew.o dtcomp.o sfclose.o sfclrlock.o sfdisc.o sfdlen.o sfexcept.o sfgetl.o sfgetu.o sfcvt.o sfecvt.o sffcvt.o sfextern.o sffilbuf.o sfflsbuf.o sfprints.o sfgetd.o sfgetr.o sfllen.o sfmode.o sfmove.o sfnew.o sfpkrd.o sfnotify.o sfnputc.o sfopen.o sfpeek.o sfpoll.o sfpool.o sfpopen.o sfprintf.o sfputd.o sfputl.o sfputr.o sfputu.o sfrd.o sfread.o sfreserve.o sfscanf.o sfseek.o sfset.o sfsetbuf.o sfsetfd.o sfsize.o sfsk.o sfstack.o sfstrtod.o sfsync.o sfswap.o sftable.o sftell.o sftmp.o sfungetc.o sfvprintf.o sfvscanf.o sfwr.o sfwrite.o sfpurge.o sfraise.o sfwalk.o sfgetm.o sfmutex.o sfputm.o sfresize.o _sfclrerr.o _sfeof.o _sferror.o _sffileno.o _sfopen.o _sfstacked.o _sfvalue.o _sfgetc.o _sfgetl.o _sfgetl2.o _sfgetu.o _sfgetu2.o _sfdlen.o _sfllen.o _sfslen.o _sfulen.o _sfputc.o _sfputd.o _sfputl.o _sfputm.o
|
||||
exec - ${AR} rc libast.a regnexec.o regsubcomp.o regsubexec.o regsub.o regrecord.o regrexec.o regstat.o dtclose.o dtdisc.o dthash.o dtlist.o dtmethod.o dtopen.o dtstat.o dtstrhash.o dttree.o dtuser.o dtview.o dtwalk.o dtnew.o dtcomp.o sfclose.o sfclrlock.o sfdisc.o sfdlen.o sfexcept.o sfgetl.o sfgetu.o sfcvt.o sfecvt.o sffcvt.o sfextern.o sffilbuf.o sfflsbuf.o sfprints.o sfgetd.o sfgetr.o sfllen.o sfmode.o sfmove.o sfnew.o sfpkrd.o sfnotify.o sfnputc.o sfopen.o sfpeek.o sfpoll.o sfpool.o sfpopen.o sfprintf.o sfputd.o sfputl.o sfputr.o sfputu.o sfrd.o sfread.o sfreserve.o sfscanf.o sfseek.o sfset.o sfsetbuf.o sfsetfd.o sfsize.o sfsk.o sfstack.o sfstrtod.o sfsync.o sfswap.o sftable.o sftell.o sftmp.o sfungetc.o sfvprintf.o sfvscanf.o sfwr.o sfwrite.o sfpurge.o sfraise.o sfwalk.o sfgetm.o sfmutex.o sfputm.o sfresize.o _sfclrerr.o _sfeof.o _sferror.o _sffileno.o _sfopen.o _sfstacked.o _sfvalue.o _sfgetc.o _sfgetl.o _sfgetl2.o _sfgetu.o _sfgetu2.o _sfdlen.o _sfllen.o _sfslen.o _sfulen.o _sfputc.o _sfputd.o _sfputl.o _sfputm.o
|
||||
exec - ${AR} rc libast.a _sfputu.o clearerr.o fclose.o fdopen.o feof.o ferror.o fflush.o fgetc.o fgetpos.o fgets.o fileno.o fopen.o fprintf.o fpurge.o fputc.o fputs.o fread.o freopen.o fscanf.o fseek.o fseeko.o fsetpos.o ftell.o ftello.o fwrite.o flockfile.o ftrylockfile.o funlockfile.o getc.o getchar.o getw.o pclose.o popen.o printf.o putc.o putchar.o puts.o putw.o rewind.o scanf.o setbuf.o setbuffer.o setlinebuf.o setvbuf.o snprintf.o sprintf.o sscanf.o asprintf.o vasprintf.o tmpfile.o ungetc.o vfprintf.o vfscanf.o vprintf.o vscanf.o vsnprintf.o vsprintf.o vsscanf.o _doprnt.o _doscan.o _filbuf.o _flsbuf.o _stdfun.o _stdopen.o _stdprintf.o _stdscanf.o _stdsprnt.o _stdvbuf.o _stdvsnprnt.o _stdvsprnt.o _stdvsscn.o fgetwc.o fwprintf.o putwchar.o vfwscanf.o wprintf.o fgetws.o fwscanf.o swprintf.o vswprintf.o wscanf.o fputwc.o getwc.o swscanf.o vswscanf.o fputws.o getwchar.o ungetwc.o vwprintf.o fwide.o putwc.o vfwprintf.o vwscanf.o stdio_c99.o fcloseall.o fmemopen.o getdelim.o getline.o frexp.o frexpl.o astcopy.o
|
||||
exec - ${AR} rc libast.a astconf.o astdynamic.o astlicense.o astquery.o astwinsize.o conftab.o aststatic.o getopt.o getoptl.o aso.o asolock.o asometh.o asorelax.o aso-sem.o aso-fcntl.o vmbest.o vmclear.o vmclose.o vmdcheap.o vmdebug.o vmdisc.o vmexit.o vmlast.o vmopen.o vmpool.o vmprivate.o vmprofile.o vmregion.o vmsegment.o vmset.o vmstat.o vmstrdup.o vmtrace.o vmwalk.o vmmopen.o malloc.o vmgetmem.o a64l.o acosh.o asinh.o atanh.o cbrt.o crypt.o erf.o err.o exp.o exp__E.o expm1.o gamma.o getpass.o lgamma.o log.o log1p.o log__L.o rand48.o random.o rcmd.o rint.o support.o sfstrtmp.o spawn.o
|
||||
exec - (ranlib libast.a) >/dev/null 2>&1 || true
|
||||
|
|
|
|||
|
|
@ -58,9 +58,9 @@
|
|||
/* This struct holds private method data created on DT_OPEN */
|
||||
struct _dtdata_s
|
||||
{ unsigned int lock; /* general dictionary lock */
|
||||
Dtuser_t user; /* application's data */
|
||||
unsigned int type; /* method type, control flags */
|
||||
ssize_t size; /* number of objects */
|
||||
Dtuser_t user; /* application's data */
|
||||
Dt_t dict; /* when DT_INDATA is requested */
|
||||
};
|
||||
|
||||
|
|
@ -123,7 +123,7 @@ typedef struct _dtlib_s
|
|||
#endif /* _BLD_cdt */
|
||||
|
||||
/* these macros lock/unlock dictionaries. DTRETURN substitutes for "return" */
|
||||
#define DTSETLOCK(dt) (((dt)->data->type&DT_SHARE) ? asolock(&(dt)->data->lock,1,ASO_SPINLOCK) : 0 )
|
||||
#define DTSETLOCK(dt) (((dt)->data->type&DT_SHARE) ? asolock(&(dt)->data->lock,1,ASO_LOCK) : 0 )
|
||||
#define DTCLRLOCK(dt) (((dt)->data->type&DT_SHARE) ? asolock(&(dt)->data->lock,1,ASO_UNLOCK) : 0 )
|
||||
#define DTRETURN(ob,rv) do { (ob) = (rv); goto dt_return; } while(0)
|
||||
#define DTERROR(dt, mesg) (!((dt)->disc && (dt)->disc->eventf) ? 0 : \
|
||||
|
|
|
|||
|
|
@ -52,9 +52,3 @@ extern ssize_t dtsize(Dt_t* d)
|
|||
{
|
||||
return (ssize_t)(*(_DT(d)->searchf))((d),(Void_t*)(0),DT_STAT);
|
||||
}
|
||||
|
||||
#undef dtstat
|
||||
extern ssize_t dtstat(Dt_t* d)
|
||||
{
|
||||
return (ssize_t)(*(_DT(d)->searchf))((d),(Void_t*)(0),DT_STAT);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -52,11 +52,13 @@ static int htable(Dt_t* dt)
|
|||
if((n = hash->tblz) > 0 && (hash->type&H_FIXED) )
|
||||
return 0; /* fixed size table */
|
||||
|
||||
if(n == 0 && disc && disc->eventf) /* let user have input */
|
||||
if(disc && disc->eventf) /* let user have input */
|
||||
{ if((*disc->eventf)(dt, DT_HASHSIZE, &n, disc) > 0 )
|
||||
{ if(n < 0) /* fix table size */
|
||||
{ hash->type |= H_FIXED;
|
||||
n = -n;
|
||||
n = -n; /* desired table size */
|
||||
if(hash->tblz >= n ) /* table size is fixed now */
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -234,12 +236,13 @@ static Void_t* hstat(Dt_t* dt, Dtstat_t* st)
|
|||
|
||||
for(endt = (t = hash->htbl) + hash->tblz; t < endt; ++t)
|
||||
{ for(n = 0, l = *t; l; l = l->_rght)
|
||||
{ if(n < DT_MAXSIZE)
|
||||
st->lsize[n] += 1;
|
||||
n += 1;
|
||||
}
|
||||
st->mlev = n > st->mlev ? n : st->mlev;
|
||||
if(n < DT_MAXSIZE) /* if chain length is small */
|
||||
{ st->msize = n > st->msize ? n : st->msize;
|
||||
st->lsize[n] += n;
|
||||
}
|
||||
st->msize = n > st->msize ? n : st->msize;
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -310,7 +313,7 @@ int type;
|
|||
hsh = _DTHSH(dt,key,disc);
|
||||
|
||||
tbl = hash->htbl + (hsh & (hash->tblz-1));
|
||||
pp = ll = NIL(Dtlink_t*);
|
||||
pp = ll = NIL(Dtlink_t*); /* pp is the before, ll is the here */
|
||||
for(p = NIL(Dtlink_t*), l = *tbl; l; p = l, l = l->_rght)
|
||||
{ if(hsh == l->_hash)
|
||||
{ o = _DTOBJ(disc,l); k = _DTKEY(disc,o);
|
||||
|
|
@ -342,20 +345,41 @@ int type;
|
|||
_dtfree(dt, ll, type);
|
||||
DTRETURN(obj, _DTOBJ(disc,ll));
|
||||
}
|
||||
else if(type & DT_INSTALL )
|
||||
{ if(dt->meth->type&DT_BAG)
|
||||
goto do_insert;
|
||||
else if(!(lnk = _dtmake(dt, obj, type)) )
|
||||
DTRETURN(obj, NIL(Void_t*) );
|
||||
else /* replace old object with new one */
|
||||
{ if(pp) /* remove old object */
|
||||
pp->_rght = ll->_rght;
|
||||
else *tbl = ll->_rght;
|
||||
o = _DTOBJ(disc,ll);
|
||||
_dtfree(dt, ll, DT_DELETE);
|
||||
DTANNOUNCE(dt, o, DT_DELETE);
|
||||
|
||||
goto do_insert;
|
||||
}
|
||||
}
|
||||
else
|
||||
{ /**/DEBUG_ASSERT(type&(DT_INSERT|DT_ATTACH|DT_APPEND|DT_RELINK));
|
||||
if(!(dt->meth->type&DT_BAG) )
|
||||
if((dt->meth->type&DT_BAG) )
|
||||
goto do_insert;
|
||||
else
|
||||
{ if(type&(DT_INSERT|DT_APPEND|DT_ATTACH) )
|
||||
type |= DT_SEARCH; /* for announcement */
|
||||
type |= DT_MATCH; /* for announcement */
|
||||
else if(lnk && (type&DT_RELINK) )
|
||||
{ /* remove a duplicate */
|
||||
o = _DTOBJ(disc, lnk);
|
||||
_dtfree(dt, lnk, DT_DELETE);
|
||||
DTANNOUNCE(dt, o, DT_DELETE);
|
||||
}
|
||||
DTRETURN(obj, _DTOBJ(disc,ll));
|
||||
}
|
||||
else goto do_insert;
|
||||
}
|
||||
}
|
||||
else /* no matching object */
|
||||
{ if(!(type&(DT_INSERT|DT_APPEND|DT_ATTACH|DT_RELINK)) )
|
||||
{ if(!(type&(DT_INSERT|DT_INSTALL|DT_APPEND|DT_ATTACH|DT_RELINK)) )
|
||||
DTRETURN(obj, NIL(Void_t*));
|
||||
|
||||
do_insert: /* inserting a new object */
|
||||
|
|
|
|||
|
|
@ -142,9 +142,9 @@ int type;
|
|||
}
|
||||
|
||||
#if __STD_C
|
||||
static Void_t* liststat(Dt_t* dt, Dtstat_t* st)
|
||||
static Void_t* listat(Dt_t* dt, Dtstat_t* st)
|
||||
#else
|
||||
static Void_t* liststat(dt, st)
|
||||
static Void_t* listat(dt, st)
|
||||
Dt_t* dt;
|
||||
Dtstat_t* st;
|
||||
#endif
|
||||
|
|
@ -186,7 +186,7 @@ int type;
|
|||
else if(type&DT_CLEAR)
|
||||
DTRETURN(obj, lclear(dt));
|
||||
else if(type&DT_STAT )
|
||||
DTRETURN(obj, liststat(dt, (Dtstat_t*)obj));
|
||||
DTRETURN(obj, listat(dt, (Dtstat_t*)obj));
|
||||
|
||||
h = list->here; /* save finger to last search object */
|
||||
list->here = NIL(Dtlink_t*);
|
||||
|
|
@ -202,8 +202,9 @@ int type;
|
|||
{ r = (Dtlink_t*)obj;
|
||||
goto do_insert;
|
||||
}
|
||||
else if(type&(DT_INSERT|DT_APPEND|DT_ATTACH))
|
||||
{ if(!(r = _dtmake(dt, obj, type)) )
|
||||
else if(type&(DT_INSERT|DT_INSTALL|DT_APPEND|DT_ATTACH))
|
||||
{ dt_insert:
|
||||
if(!(r = _dtmake(dt, obj, type)) )
|
||||
DTRETURN(obj, NIL(Void_t*));
|
||||
dt->data->size += 1;
|
||||
|
||||
|
|
@ -290,7 +291,7 @@ int type;
|
|||
}
|
||||
r = h ? h : r;
|
||||
}
|
||||
if(!r)
|
||||
if(!r) /* not found */
|
||||
DTRETURN(obj, NIL(Void_t*));
|
||||
|
||||
if(type&(DT_DELETE|DT_DETACH|DT_REMOVE))
|
||||
|
|
|
|||
|
|
@ -153,25 +153,3 @@ void _dtfree(Dt_t* dt, Dtlink_t* l, int type)
|
|||
if(disc->link < 0) /* free holder */
|
||||
(void)(*dt->memoryf)(dt, (Void_t*)l, 0, disc);
|
||||
}
|
||||
|
||||
int dtuserlock(Dt_t* dt, unsigned int key, int type)
|
||||
{
|
||||
if(type > 0)
|
||||
return asolock(&dt->data->user.lock, key, ASO_LOCK);
|
||||
else if(type < 0)
|
||||
return asolock(&dt->data->user.lock, key, ASO_UNLOCK);
|
||||
else return asolock(&dt->data->user.lock, key, ASO_TRYLOCK);
|
||||
}
|
||||
|
||||
Void_t* dtuserdata(Dt_t* dt, Void_t* data, unsigned int key)
|
||||
{
|
||||
if(key == 0)
|
||||
return dt->data->user.data;
|
||||
else if(dtuserlock(dt, key, 1) < 0 )
|
||||
return NIL(Void_t*);
|
||||
else
|
||||
{ dt->data->user.data = data;
|
||||
dtuserlock(dt, key, -1);
|
||||
return data;
|
||||
}
|
||||
}
|
||||
|
|
|
|||
54
src/lib/libast/cdt/dtstat.c
Normal file
54
src/lib/libast/cdt/dtstat.c
Normal file
|
|
@ -0,0 +1,54 @@
|
|||
/***********************************************************************
|
||||
* *
|
||||
* This software is part of the ast package *
|
||||
* Copyright (c) 1985-2012 AT&T Intellectual Property *
|
||||
* and is licensed under the *
|
||||
* Eclipse Public License, Version 1.0 *
|
||||
* by AT&T Intellectual Property *
|
||||
* *
|
||||
* A copy of the License is available at *
|
||||
* http://www.eclipse.org/org/documents/epl-v10.html *
|
||||
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
|
||||
* *
|
||||
* Information and Software Systems Research *
|
||||
* AT&T Research *
|
||||
* Florham Park NJ *
|
||||
* *
|
||||
* Glenn Fowler <gsf@research.att.com> *
|
||||
* David Korn <dgk@research.att.com> *
|
||||
* Phong Vo <kpv@research.att.com> *
|
||||
* *
|
||||
***********************************************************************/
|
||||
#include "dthdr.h"
|
||||
|
||||
/* Get statistics for a dictionary
|
||||
**
|
||||
** Written by Kiem-Phong Vo
|
||||
*/
|
||||
|
||||
ssize_t dtstat(Dt_t* dt, Dtstat_t* dtst)
|
||||
{
|
||||
ssize_t sz, k, maxk;
|
||||
char *str;
|
||||
char *end;
|
||||
|
||||
sz = (ssize_t)(*dt->meth->searchf)(dt, (Void_t*)dtst, DT_STAT);
|
||||
|
||||
str = dtst->mesg;
|
||||
end = &dtst->mesg[sizeof(dtst->mesg)] - 1;
|
||||
str += sfsprintf(str, end - str, "Objects=%d Levels=%d(Largest:", dtst->size, dtst->mlev+1);
|
||||
|
||||
/* print top 3 levels */
|
||||
for(k = maxk = 0; k <= dtst->mlev; ++k)
|
||||
if(dtst->lsize[k] > dtst->lsize[maxk])
|
||||
maxk = k;
|
||||
if(maxk > 0)
|
||||
maxk -= 1;
|
||||
for(k = 0; k < 3 && maxk <= dtst->mlev; ++k, ++maxk)
|
||||
str += sfsprintf(str, end - str, " lev[%d]=%d", maxk, dtst->lsize[maxk] );
|
||||
if (str < end)
|
||||
*str++ = ')';
|
||||
*str = 0;
|
||||
|
||||
return sz;
|
||||
}
|
||||
|
|
@ -22,40 +22,38 @@
|
|||
#include "dthdr.h"
|
||||
|
||||
/* Hashing a string into an unsigned integer.
|
||||
** The basic method is to continuingly accumulate bytes and multiply
|
||||
** with some given prime. The length n of the string is added last.
|
||||
** The recurrent equation is like this:
|
||||
** h[k] = (h[k-1] + bytes)*prime for 0 <= k < n
|
||||
** h[n] = (h[n-1] + n)*prime
|
||||
** The prime is chosen to have a good distribution of 1-bits so that
|
||||
** the multiplication will distribute the bits in the accumulator well.
|
||||
** The below code accumulates 2 bytes at a time for speed.
|
||||
**
|
||||
** Written by Kiem-Phong Vo (02/28/03)
|
||||
** This is the FNV (Fowler-Noll-Vo) hash function.
|
||||
** Written by Kiem-Phong Vo (01/10/2012)
|
||||
*/
|
||||
|
||||
#if __STD_C
|
||||
uint dtstrhash(uint h, Void_t* args, ssize_t n)
|
||||
#else
|
||||
uint dtstrhash(h,args,n)
|
||||
reg uint h;
|
||||
uint h;
|
||||
Void_t* args;
|
||||
ssize_t n;
|
||||
#endif
|
||||
{
|
||||
unsigned char *s = (unsigned char*)args;
|
||||
|
||||
if(n <= 0)
|
||||
{ for(; *s != 0; s += s[1] ? 2 : 1)
|
||||
h = (h + (s[0]<<8) + s[1])*DT_PRIME;
|
||||
n = s - (unsigned char*)args;
|
||||
#if _ast_sizeof_int == 8 /* 64-bit hash */
|
||||
#define FNV_PRIME ((1<<40) + (1<<8) + 0xb3)
|
||||
#define FNV_OFFSET 14695981039346656037
|
||||
#else /* 32-bit hash */
|
||||
#define FNV_PRIME ((1<<24) + (1<<8) + 0x93)
|
||||
#define FNV_OFFSET 2166136261
|
||||
#endif
|
||||
h = (h == 0 || h == ~0) ? FNV_OFFSET : h;
|
||||
if(n <= 0) /* see discipline key definition for == 0 */
|
||||
{ for(; *s != 0; ++s )
|
||||
h = (h ^ s[0]) * FNV_PRIME;
|
||||
}
|
||||
else
|
||||
{ unsigned char* ends;
|
||||
for(ends = s+n-1; s < ends; s += 2)
|
||||
h = (h + (s[0]<<8) + s[1])*DT_PRIME;
|
||||
if(s <= ends)
|
||||
h = (h + (s[0]<<8))*DT_PRIME;
|
||||
for(ends = s+n; s < ends; ++s)
|
||||
h = (h ^ s[0]) * FNV_PRIME;
|
||||
}
|
||||
return (h+n)*DT_PRIME;
|
||||
|
||||
return h;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -545,7 +545,14 @@ int type;
|
|||
}
|
||||
else goto no_root;
|
||||
}
|
||||
else if(type&DT_REMOVE) /* remove a particular element in the tree */
|
||||
else if(type&(DT_DELETE|DT_DETACH))
|
||||
{ dt_delete: /* remove an object from the dictionary */
|
||||
obj = _DTOBJ(disc,root);
|
||||
_dtfree(dt, root, type);
|
||||
dt->data->size -= 1;
|
||||
goto no_root;
|
||||
}
|
||||
else if(type&DT_REMOVE) /* remove a particular object */
|
||||
{ if(_DTOBJ(disc,root) == obj)
|
||||
goto dt_delete;
|
||||
else
|
||||
|
|
@ -555,28 +562,32 @@ int type;
|
|||
DTRETURN(obj, NIL(Void_t*));
|
||||
}
|
||||
}
|
||||
else if(type&(DT_DELETE|DT_DETACH))
|
||||
{ dt_delete: /* remove an object from the dictionary */
|
||||
obj = _DTOBJ(disc,root);
|
||||
_dtfree(dt, root, type);
|
||||
dt->data->size -= 1;
|
||||
goto no_root;
|
||||
}
|
||||
else if(type&(DT_INSERT|DT_APPEND|DT_ATTACH))
|
||||
{ if(dt->meth->type&DT_OSET)
|
||||
{ type |= DT_SEARCH; /* for announcement */
|
||||
{ type |= DT_MATCH; /* for announcement */
|
||||
goto has_root;
|
||||
}
|
||||
else
|
||||
else /* if(dt->meth->type&DT_OBAG) */
|
||||
{ root->_left = NIL(Dtlink_t*);
|
||||
root->_rght = link._left;
|
||||
link._left = root;
|
||||
goto dt_insert;
|
||||
}
|
||||
}
|
||||
else if(type&DT_INSTALL)
|
||||
{ /* remove old object before insert new one */
|
||||
o = _DTOBJ(disc, root);
|
||||
_dtfree(dt, root, DT_DELETE);
|
||||
DTANNOUNCE(dt, o, DT_DELETE);
|
||||
goto dt_insert;
|
||||
}
|
||||
else if(type&DT_RELINK) /* a duplicate */
|
||||
{ if(dt->meth->type&DT_OSET)
|
||||
{ /* remove object */
|
||||
o = _DTOBJ(disc, me);
|
||||
_dtfree(dt, me, DT_DELETE);
|
||||
DTANNOUNCE(dt, o, DT_DELETE);
|
||||
}
|
||||
else
|
||||
{ me->_left = NIL(Dtlink_t*);
|
||||
me->_rght = link._left;
|
||||
|
|
@ -612,7 +623,7 @@ int type;
|
|||
{ obj = NIL(Void_t*);
|
||||
goto no_root;
|
||||
}
|
||||
else if(type&(DT_INSERT|DT_APPEND|DT_ATTACH))
|
||||
else if(type&(DT_INSERT|DT_APPEND|DT_ATTACH|DT_INSTALL))
|
||||
{ dt_insert:
|
||||
if(!(root = _dtmake(dt, obj, type)) )
|
||||
{ obj = NIL(Void_t*);
|
||||
|
|
|
|||
59
src/lib/libast/cdt/dtuser.c
Normal file
59
src/lib/libast/cdt/dtuser.c
Normal file
|
|
@ -0,0 +1,59 @@
|
|||
/***********************************************************************
|
||||
* *
|
||||
* This software is part of the ast package *
|
||||
* Copyright (c) 1985-2012 AT&T Intellectual Property *
|
||||
* and is licensed under the *
|
||||
* Eclipse Public License, Version 1.0 *
|
||||
* by AT&T Intellectual Property *
|
||||
* *
|
||||
* A copy of the License is available at *
|
||||
* http://www.eclipse.org/org/documents/epl-v10.html *
|
||||
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
|
||||
* *
|
||||
* Information and Software Systems Research *
|
||||
* AT&T Research *
|
||||
* Florham Park NJ *
|
||||
* *
|
||||
* Glenn Fowler <gsf@research.att.com> *
|
||||
* David Korn <dgk@research.att.com> *
|
||||
* Phong Vo <kpv@research.att.com> *
|
||||
* *
|
||||
***********************************************************************/
|
||||
#include "dthdr.h"
|
||||
|
||||
/* Perform various functions on the user's behalf.
|
||||
**
|
||||
** Written by Kiem-Phong Vo (01/05/2012)
|
||||
*/
|
||||
|
||||
/* managing the lock dt->data->user.lock */
|
||||
int dtuserlock(Dt_t* dt, unsigned int key, int type)
|
||||
{
|
||||
if(key == 0)
|
||||
return -1;
|
||||
else if(type > 0)
|
||||
return asolock(&dt->data->user.lock, key, ASO_LOCK);
|
||||
else if(type < 0)
|
||||
return asolock(&dt->data->user.lock, key, ASO_UNLOCK);
|
||||
else return asolock(&dt->data->user.lock, key, ASO_TRYLOCK);
|
||||
}
|
||||
|
||||
/* managing the user data slot dt->data->user.data */
|
||||
Void_t* dtuserdata(Dt_t* dt, Void_t* data, int set)
|
||||
{
|
||||
if(set == 0) /* just return current value */
|
||||
return asogetptr(&dt->data->user.data);
|
||||
else while(1)
|
||||
{ Void_t *current = dt->data->user.data;
|
||||
if(asocasptr(&dt->data->user.data, current, data) == current)
|
||||
return current;
|
||||
}
|
||||
}
|
||||
|
||||
/* announcing an event on the user's behalf */
|
||||
int dtuserevent(Dt_t* dt, int flags, Void_t* data)
|
||||
{
|
||||
if(!dt->disc->eventf)
|
||||
return 0;
|
||||
else return (*dt->disc->eventf)(dt, DT_ANNOUNCE|DT_USER|flags, data, dt->disc);
|
||||
}
|
||||
|
|
@ -164,6 +164,7 @@ struct _dtstat_s
|
|||
ssize_t msize; /* max #defined elts in below arrays */
|
||||
ssize_t lsize[DT_MAXSIZE]; /* #objects by level */
|
||||
ssize_t tsize[DT_MAXSIZE]; /* #tables by level */
|
||||
char mesg[256]; /* digest of top level statistics */
|
||||
};
|
||||
|
||||
/* supported storage methods */
|
||||
|
|
@ -199,7 +200,8 @@ struct _dtstat_s
|
|||
#define DT_ATLEAST 0000040000 /* find the least elt >= object */
|
||||
#define DT_ATMOST 0000100000 /* find the biggest elt <= object */
|
||||
#define DT_REMOVE 0002000000 /* remove a specific object */
|
||||
#define DT_TOANNOUNCE (DT_INSERT|DT_DELETE|DT_SEARCH|DT_NEXT|DT_PREV|DT_FIRST|DT_LAST|DT_MATCH|DT_ATTACH|DT_DETACH|DT_APPEND|DT_ATLEAST|DT_ATMOST|DT_REMOVE)
|
||||
#define DT_INSTALL 0004000000 /* install a new object */
|
||||
#define DT_TOANNOUNCE (DT_INSERT|DT_DELETE|DT_SEARCH|DT_NEXT|DT_PREV|DT_FIRST|DT_LAST|DT_MATCH|DT_ATTACH|DT_DETACH|DT_APPEND|DT_ATLEAST|DT_ATMOST|DT_REMOVE|DT_INSTALL)
|
||||
|
||||
#define DT_RELINK 0000002000 /* re-inserting (dtdisc,dtmethod...) */
|
||||
#define DT_FLATTEN 0000000040 /* flatten objects into a list */
|
||||
|
|
@ -216,6 +218,7 @@ struct _dtstat_s
|
|||
/* the actual event will be this bit */
|
||||
/* combined with the operation bit */
|
||||
#define DT_OPTIMIZE 0100000000 /* optimizing data structure */
|
||||
#define DT_USER 0200000000 /* an announcement on user's behalf */
|
||||
|
||||
/* events for discipline and method event-handling functions */
|
||||
#define DT_OPEN 1 /* a dictionary is being opened */
|
||||
|
|
@ -277,7 +280,8 @@ extern int dtwalk _ARG_((Dt_t*, int(*)(Dt_t*,Void_t*,Void_t*), Void_t*));
|
|||
extern int dtcustomize _ARG_((Dt_t*, int, int));
|
||||
extern unsigned int dtstrhash _ARG_((unsigned int, Void_t*, ssize_t));
|
||||
extern int dtuserlock _ARG_((Dt_t*, unsigned int, int));
|
||||
extern Void_t* dtuserdata _ARG_((Dt_t*, Void_t*, unsigned int));
|
||||
extern Void_t* dtuserdata _ARG_((Dt_t*, Void_t*, int));
|
||||
extern int dtuserevent _ARG_((Dt_t*, int, Void_t*));
|
||||
|
||||
/* deal with upward binary compatibility (operation bit translation, etc.) */
|
||||
extern Dt_t* _dtopen _ARG_((Dtdisc_t*, Dtmethod_t*, unsigned long));
|
||||
|
|
@ -334,6 +338,7 @@ _END_EXTERNS_
|
|||
#define dtsearch(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_SEARCH)
|
||||
#define dtmatch(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_MATCH)
|
||||
#define dtinsert(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_INSERT)
|
||||
#define dtinstall(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_INSTALL)
|
||||
#define dtappend(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_APPEND)
|
||||
#define dtdelete(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_DELETE)
|
||||
#define dtremove(d,o) (*(_DT(d)->searchf))((d),(Void_t*)(o),DT_REMOVE)
|
||||
|
|
@ -345,7 +350,6 @@ _END_EXTERNS_
|
|||
#define dtextract(d) (Dtlink_t*)(*(_DT(d)->searchf))((d),(Void_t*)(0),DT_EXTRACT)
|
||||
#define dtrestore(d,l) (Dtlink_t*)(*(_DT(d)->searchf))((d),(Void_t*)(l),DT_RESTORE)
|
||||
|
||||
#define dtstat(d,s) (ssize_t)(*(_DT(d)->searchf))((d),(Void_t*)(s),DT_STAT)
|
||||
#define dtsize(d) (ssize_t)(*(_DT(d)->searchf))((d),(Void_t*)(0),DT_STAT)
|
||||
|
||||
#define DT_PRIME 17109811 /* 2#00000001 00000101 00010011 00110011 */
|
||||
|
|
|
|||
|
|
@ -33,6 +33,7 @@ Dtdisc_t;
|
|||
Dtmethod_t;
|
||||
Dtlink_t;
|
||||
Dtstat_t;
|
||||
Dtuser_t;
|
||||
.Ce
|
||||
.Ss "DICTIONARY CONTROL"
|
||||
.Cs
|
||||
|
|
@ -42,10 +43,10 @@ void dtclear(dt);
|
|||
Dtdisc_t* dtdisc(Dt_t* dt, const Dtdisc_t* disc, int type);
|
||||
Dtmethod_t* dtmethod(Dt_t* dt, const Dtmethod_t* meth);
|
||||
Dt_t* dtview(Dt_t* dt, Dt_t* view);
|
||||
int dtcustomize(Dt_t* dt, int type, Void_t* arg);
|
||||
int dtoptimize(Dt_t* dt);
|
||||
int dtshare(Dt_t* dt, int type);
|
||||
int dtlock(Dt_t* dt, unsigned int key, int type);
|
||||
int dtcustomize(Dt_t* dt, int type, int action);
|
||||
int dtuserlock(Dt_t* dt, unsigned int key, int action);
|
||||
Void_t* dtuserdata(Dt_t* dt, Void_t* data, int set);
|
||||
int dtuserevent(Dt_t* dt, int flags, Void_t* data);
|
||||
.Ce
|
||||
.Ss "STORAGE METHODS"
|
||||
.Cs
|
||||
|
|
@ -74,8 +75,10 @@ typedef int (*Dtevent_f)(Dt_t*, int, Void_t*, Dtdisc_t*);
|
|||
.Ss "OBJECT OPERATIONS"
|
||||
.Cs
|
||||
Void_t* dtinsert(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtinstall(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtappend(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtdelete(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtremove(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtattach(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtdetach(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtsearch(Dt_t* dt, Void_t* obj);
|
||||
|
|
@ -84,9 +87,12 @@ Void_t* dtfirst(Dt_t* dt);
|
|||
Void_t* dtnext(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtlast(Dt_t* dt);
|
||||
Void_t* dtprev(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtleast(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtmost(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtatleast(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtatmost(Dt_t* dt, Void_t* obj);
|
||||
int dtwalk(Dt_t* dt, int (*userf)(Dt_t*, Void_t*, Void_t*), Void_t*);
|
||||
Void_t* dtstart(Dt_t* dt, Void_t* obj);
|
||||
Void_t* dtstep(Dt_t* dt, Void_t* path);
|
||||
Void_t* dtstop(Dt_t* dt, Void_t* path);
|
||||
Dtlink_t* dtflatten(Dt_t* dt);
|
||||
Dtlink_t* dtlink(Dt_t* dt, Dtlink_t* link);
|
||||
Void_t* dtobj(Dt_t* dt, Dtlink_t* link);
|
||||
|
|
@ -101,10 +107,9 @@ Dt_t* dtvhere(Dt_t* dt);
|
|||
ssize_t dtsize(Dt_t* dt);
|
||||
ssize_t dtstat(Dt_t* dt, Dtstat_t* st);
|
||||
.Ce
|
||||
.Ss "HASH FUNCTIONS"
|
||||
.Ss "HASH FUNCTION"
|
||||
.Cs
|
||||
unsigned int dtstrhash(unsigned int h, char* str, int n);
|
||||
unsigned int dtcharhash(unsigned int h, unsigned char c);
|
||||
.Ce
|
||||
.SH DESCRIPTION
|
||||
.PP
|
||||
|
|
@ -120,6 +125,7 @@ and \f5char\fP for older C compilation environments.
|
|||
.PP
|
||||
.Ss " Dt_t"
|
||||
This is the type of a dictionary handle.
|
||||
It contains a field \f5Dt_t.user\fP of type \f5Dtuser_t*\fP (see below).
|
||||
.PP
|
||||
.Ss " Dtdisc_t"
|
||||
This defines the type of a discipline structure which define the lay-out of
|
||||
|
|
@ -134,6 +140,22 @@ This is the type of a dictionary object holder (see \f5dtdisc()\fP.)
|
|||
.Ss " Dtstat_t"
|
||||
This is the type of a structure to return dictionary statistics (see \f5dtstat()\fP.)
|
||||
.PP
|
||||
.Ss " Dtuser_t"
|
||||
This is the type of a structure pointed to by \f5Dt_t.user\fP.
|
||||
If a discipline function \f5memoryf()\fP was defined, this structure
|
||||
will reside in memory allocated via \f5memoryf\fP.
|
||||
Although the structure is intended to be used by an application outside of CDT operations,
|
||||
the functions \f5dtuserlock()\fP and \f5dtuserdata()\fP
|
||||
are provided for certain common usages of the defined fields.
|
||||
It should be emphasized, however, that a particular application can choose
|
||||
to use this structure in anyway that it sees fit.
|
||||
.Cs
|
||||
typedef struct
|
||||
{ unsigned int lock; /* for locking a shared dictionary */
|
||||
Void_t* data; /* for application-specific data */
|
||||
} Dtuser_t;
|
||||
.Ce
|
||||
.PP
|
||||
.Ss "DICTIONARY CONTROL"
|
||||
.PP
|
||||
.Ss " Dt_t* dtopen(const Dtdisc_t* disc, const Dtmethod_t* meth)"
|
||||
|
|
@ -183,50 +205,63 @@ In addition, dictionaries on the same view path should
|
|||
treat objects in a consistent manner with respect to comparison or hashing.
|
||||
If not, undefined behaviors may result.
|
||||
.PP
|
||||
.Ss " int dtcustomize(Dt_t* dt, int type, Void_t* arg)"
|
||||
.Ss " int dtcustomize(Dt_t* dt, int type, int action)"
|
||||
This customizes a storage method. The \f5type\fP argument
|
||||
indicates the type of customization and \f5arg\fP gives additional
|
||||
information for the operation. Here are the types:
|
||||
is composed of bits indicating different types of customization.
|
||||
The \f5action\fP argument, if positive, turns on the desired customization;
|
||||
else, turning it off.
|
||||
The return value is a bit vector telling the customization types successfully performed.
|
||||
|
||||
Here are the types:
|
||||
.Tp
|
||||
\f5DT_SHARE\fP:
|
||||
This turns on/off the share mode for a dictionary.
|
||||
Concurrent accesses of a dictionary not in share mode
|
||||
may exhibit undefined behaviors including memory segmentation.
|
||||
|
||||
Share mode allows multiple accessors, threads or processes, to access objects.
|
||||
Such objects could be in the same directory in the case of threads or shared
|
||||
memory in the case of processes.
|
||||
This controls the shared or concurrent mode for a dictionary.
|
||||
Shared mode allows concurrent threads or processes to safely
|
||||
access objects in a dictionary.
|
||||
.Tp
|
||||
\f5DT_ANNOUNCE\fP:
|
||||
This requires each dictionary access operation to invoke
|
||||
the discipline \f5eventf\fP function to announce an object found or constructed
|
||||
by the operation before returning (See the DISCIPLINE section below).
|
||||
.Tp
|
||||
\f5DT_OPTIMIZE\fP:
|
||||
This causes the underlying method to optimize its internal
|
||||
data structure. For example, the splay tree underlying \f5Dtoset\fP
|
||||
would be balanced.
|
||||
.PP
|
||||
.Ss " int dtoptimize(Dt_t* dt)"
|
||||
This is a short-hand for invoking \f5dtcustomize()\fP with the \f5DT_OPTIMIZE\fP event.
|
||||
.PP
|
||||
.Ss " int dtshare(Dt_t* dt, int type)"
|
||||
This turns on or off share mode for dictionary \f5dt\fP depending on whether \f5type\fP
|
||||
is positive or non-positive. It returns -1 on failure.
|
||||
.PP
|
||||
.Ss " int dtlock(Dt_t* dt, unsigned int key, int type)"
|
||||
This globally locks/unlocks a dictionary using the given \f5key\fP.
|
||||
.Ss " int dtuserlock(Dt_t* dt, unsigned int key, int action)"
|
||||
This manipulates the lock \f5dt->user->lock\fP.
|
||||
It returns 0 on success and -1 on failure.
|
||||
The value of \f5key\fP must not be 0.
|
||||
The argument \f5type\fP is used as follows:
|
||||
The value of \f5key\fP must be non-zero.
|
||||
The argument \f5action\fP is used as follows:
|
||||
.Tp
|
||||
\f5type < 0\fP:
|
||||
Unlock the dictionary if it was locked with \f5key\fP.
|
||||
An error will result if the dictionary was locked with a different key.
|
||||
\f5action < 0\fP:
|
||||
Unlock \f5dt->user.lock\fP if it was locked with \f5key\fP.
|
||||
An error will result if \f5dt->user->lock\fP was locked with a different key.
|
||||
.Tp
|
||||
\f5type == 0\fP:
|
||||
Attempt to lock the dictionary with \f5key\fP if it is unlocked.
|
||||
\f5action == 0\fP:
|
||||
Attempt to lock \f5dt->user->lock\fP with \f5key\fP if it is unlocked.
|
||||
An error will result if the dictionary was already locked with a different key.
|
||||
.Tp
|
||||
\f5type > 0\fP:
|
||||
Attempt to lock the dictionary with \f5key\fP.
|
||||
If the dictionary is already locked with a different key,
|
||||
the call will loop and wait until the lock is open to lock it.
|
||||
\f5action > 0\fP:
|
||||
Attempt to lock \f5dt->user->lock\fP with \f5key\fP.
|
||||
If \f5dt->user.lock\fP is already locked with a different key,
|
||||
the call will block until \f5dt->user->lock\fP can be locked with the given \f5key\fP.
|
||||
|
||||
Note that obtaining or removing a lock with \f5dtuserlock()\fP
|
||||
is just a service provided to the
|
||||
application for their own use and has nothing to do with dictionary operations
|
||||
which may or may not employ their own locking schemes based on the semantics
|
||||
of the container data structures in use.
|
||||
.PP
|
||||
.Ss " Void_t* dtuserdata(Dt_t* dt, Void_t* data, int set)"
|
||||
This function returns the current value of \f5dt->user->data\fP.
|
||||
In addition, if \f5set\fP is non-zero,
|
||||
the value of \f5dt->user->data\fP will be changed to \f5data\fP.
|
||||
.PP
|
||||
.Ss " int dtuserevent(Dt_t* dt, int flags, Void_t* data)"
|
||||
This function invokes the discipline event function
|
||||
with the event \f5DT_ANNOUNCE|DT_USER|flags\fP and the given data.
|
||||
|
||||
.PP
|
||||
.Ss "STORAGE METHODS"
|
||||
|
|
@ -252,13 +287,14 @@ The underlying data structure is a hash table with chaining to handle collisions
|
|||
These methods are like \f5Dtset\fP and \f5Dtbag\fP but are based on
|
||||
a recursive hashing data structure that allows table extension without
|
||||
object relocation. The data structure also supports lock-free
|
||||
concurrent search operations for share dictionaries.
|
||||
concurrent search operations for shared dictionaries and nearly lock-free
|
||||
insertions and deletions.
|
||||
.PP
|
||||
.Ss " Dtlist"
|
||||
Objects are kept in a list.
|
||||
\fIA current object\fP is always defined to be either the head of
|
||||
the list or an object resulting from a recent search or insert operation.
|
||||
The call \f5dtinsert()\fP will insert a new object
|
||||
The calls \f5dtinsert()\fP and \f5dtinstall()\fP will insert a new object
|
||||
in front of such a current object
|
||||
while the call \f5dtappend()\fP will append in back of it.
|
||||
.PP
|
||||
|
|
@ -313,7 +349,7 @@ i.e., at address \f5(Dtlink_t*)((char*)obj+link)\fP.
|
|||
.PP
|
||||
.Ss " Void_t* (*makef)(Dt_t* dt, Void_t* obj, Dtdisc_t* disc)"
|
||||
If \f5makef\fP is not \f5NULL\fP,
|
||||
\f5dtinsert(dt,obj)\fP or \f5dtappend()\fP will call it
|
||||
\f5dtinsert()\fP, \f5dtinstall()\fP or \f5dtappend()\fP will call it
|
||||
to make a copy of \f5obj\fP suitable for insertion into \f5dt\fP.
|
||||
If \f5makef\fP is \f5NULL\fP, \f5obj\fP itself will be inserted into \f5dt\fP.
|
||||
.PP
|
||||
|
|
@ -362,11 +398,11 @@ On a negative return value, \f5dtopen()\fP will return failure.
|
|||
|
||||
On a zero return value, \f5eventf()\fP may set \f5*(Void_t**)data\fP to some non-\f5NULL\fP
|
||||
value to indicate that the dictionary structure itself should be allocated
|
||||
along with the \f5Dtdisc_t.data\fP section.
|
||||
along with the \f5Dt_t.data\fP section.
|
||||
Otherwise, it will be allocated separately with \f5malloc(3)\fP.
|
||||
|
||||
On a positive return value, the dictionary is being reconstructed
|
||||
based on existing states of some previous dictionary.
|
||||
based on the existing states of some previous dictionary.
|
||||
In this case, \f5eventf()\fP should set \f5*(Void_t**)data\fP to point to
|
||||
the field \f5Dt_t.data\fP of the corresponding previous dictionary (see \f5DT_CLOSE\fP below).
|
||||
If the handle of the previous dictionary was created as discussed above
|
||||
|
|
@ -386,7 +422,7 @@ The return value of \f5eventf\fP is significant as follows:
|
|||
On a negative return value, \f5dtclose()\fP will return failure.
|
||||
|
||||
On a zero return value, all dictionary objects will be deleted and
|
||||
and all associated memory will be freed.
|
||||
and associated memory freed.
|
||||
|
||||
On a positive return value, allocated objects and memory will be kept intact.
|
||||
This means that \f5dt->data\fP remains intact and can be reused in some future
|
||||
|
|
@ -398,31 +434,60 @@ This event is raised at the end of the process to close a dictionary.
|
|||
The return value of \f5eventf()\fP will be ignored.
|
||||
.Tp
|
||||
\f5DT_DISC\fP:
|
||||
The discipline of \f5dt\fP is being changed to a new one given in
|
||||
This event indicates that the discipline of \f5dt\fP is being changed to a new one given in
|
||||
\f5(Dtdisc_t*)data\fP.
|
||||
.Tp
|
||||
\f5DT_METH\fP:
|
||||
The method of \f5dt\fP is being changed to a new one given in
|
||||
This event indicates that the method of \f5dt\fP is being changed to a new one given in
|
||||
\f5(Dtmethod_t*)data\fP.
|
||||
.Tp
|
||||
\f5DT_HASHSIZE\fP:
|
||||
This event is applicable to
|
||||
the methods \f5Dtset\fP, \f5Dtbag\fP, \f5Dtrhset\fP and \f5Dtrhbag\fP.
|
||||
It is typically issued when the respective internal data structure of
|
||||
a method is about to be initialized.
|
||||
If the return value of the event handling function is positive,
|
||||
\f5*(ssize_t*)data\fP is examined for further action;
|
||||
else, it is ignored.
|
||||
A positive return value means that the event function wishes to suggest a table size.
|
||||
It does that by setting \f5*(ssize_t*)data\fP to the desired size.
|
||||
Then, the actual table size will be the maximum of the absolute value
|
||||
of \f5*(ssize_t*)data\fP and some predefined value set by the method.
|
||||
In addition, if \f5*(ssize_t*)data\fP was negative,
|
||||
the \f5Dtset\fP and \f5Dtbag\fP methods will never resize the hash table.
|
||||
This event is raised by the methods \f5Dtset\fP, \f5Dtbag\fP, \f5Dtrhset\fP and \f5Dtrhbag\fP
|
||||
to ask an application to suggest a size (measured in objects) for the data structure in use.
|
||||
This is useful, for example, to set a initial size for a hash table to reduce collisions and rehashing.
|
||||
On each call, \f5*(ssize_t*)data\fP will initially have the current size
|
||||
(which should be \f50\fP on the first call).
|
||||
|
||||
The return value of the event handling function indicates actions to be taken.
|
||||
If non-positive, the method will proceed with its default actions.
|
||||
Otherwise, the application may set \f5*(ssize_t*)data\fP to suggest a table size.
|
||||
The actual table size will be based on the absolute value of \f5*(ssize_t*)data\fP
|
||||
but may be modified to suit for the data structure in use.
|
||||
Further, if \f5*(ssize_t*)data\fP was negative, the size of the hash table will be fixed going forward.
|
||||
.Tp
|
||||
\f5DT_ERROR\fP:
|
||||
This event announces an error that occurred during some operations.
|
||||
The argument \f5(char*)data\fP is a null-terminated string describing the error.
|
||||
This event states an error that occurred during some operations, e.g.,
|
||||
\f5dtinsert()\fP or \f5dtinstall()\fP failing to create a new object due to a memory allocation error.
|
||||
The argument \f5(char*)data\fP is a null-terminated string describing the problem.
|
||||
.Tp
|
||||
\f5DT_ANNOUNCE\fP:
|
||||
The event will be a combination of this bit and a bit indicating a successful operation.
|
||||
For example, \f5DT_ANNOUNCE|DT_SEARCH\fP announces that \f5dtsearch()\fP
|
||||
found the object that was searched for. The \f5data\fP argument points to the object itself.
|
||||
|
||||
The bits representing operations that can cause an announcement are:
|
||||
\f5DT_INSERT\fP,
|
||||
\f5DT_DELETE\fP,
|
||||
\f5DT_REMOVE\fP,
|
||||
\f5DT_SEARCH\fP,
|
||||
\f5DT_NEXT\fP,
|
||||
\f5DT_PREV\fP,
|
||||
\f5DT_FIRST\fP,
|
||||
\f5DT_LAST\fP,
|
||||
\f5DT_MATCH\fP,
|
||||
\f5DT_ATTACH\fP,
|
||||
\f5DT_DETACH\fP,
|
||||
\f5DT_APPEND\fP,
|
||||
\f5DT_INSTALL\fP,
|
||||
\f5DT_LEAST\fP, and
|
||||
\f5DT_MOST\fP.
|
||||
|
||||
Note that a call to \f5dtinsert()\fP or \f5dtattach()\fP may return
|
||||
a successfully inserted new object or a found matching object.
|
||||
For \f5dtinsert()\fP, the former case will be announced as \f5DT_ANNOUNCE|DT_INSERT\fP while
|
||||
the latter as \f5DT_ANNOUNCE|DT_INSERT|DT_SEARCH\fP.
|
||||
For \f5dtattach()\fP, the events will be similarly announced as \f5DT_ANNOUNCE|DT_ATTACH\fP
|
||||
and \f5DT_ANNOUNCE|DT_ATTACH|DT_SEARCH\fP.
|
||||
.PP
|
||||
.Ss "#define DTOFFSET(struct_s,member)"
|
||||
This macro function computes the offset of \f5member\fP from the start
|
||||
|
|
@ -436,25 +501,30 @@ with the given values.
|
|||
.Ss "OBJECT OPERATIONS"
|
||||
.PP
|
||||
.Ss " Void_t* dtinsert(Dt_t* dt, Void_t* obj)"
|
||||
.Ss " Void_t* dtinstall(Dt_t* dt, Void_t* obj)"
|
||||
.Ss " Void_t* dtappend(Dt_t* dt, Void_t* obj)"
|
||||
These functions add an object prototyped by \f5obj\fP into \f5dt\fP.
|
||||
See \f5Dtdisc_t.makef\fP for object construction.
|
||||
\f5dtinsert()\fP and \f5dtappend()\fP perform the same function
|
||||
for all methods except for \f5Dtlist\fP (see \f5Dtlist\fP for details).
|
||||
If there is an existing object in \f5dt\fP matching \f5obj\fP
|
||||
and the storage method is \f5Dtset\fP, \f5Dtrhset\fP or \f5Dtoset\fP,
|
||||
\f5dtinsert()\fP and \f5dtappend()\fP will simply return the matching object.
|
||||
Otherwise, a new object is inserted according to the method in use.
|
||||
See \f5Dtdisc_t.makef\fP for object construction.
|
||||
The new object or a matching object as noted will be returned on success
|
||||
while \f5NULL\fP is returned on error.
|
||||
For \f5Dtset\fP, \f5Dtrhset\fP or \f5Dtoset\fP,
|
||||
if there is an object in \f5dt\fP matching \f5obj\fP
|
||||
\f5dtinsert()\fP and \f5dtappend()\fP will not insert a new object.
|
||||
On the other hand, \f5dtinstall()\fP remove such a matching
|
||||
object then insert the new object.
|
||||
|
||||
On failure, \f5dtinsert()\fP and \f5dtinstall()\fP return \f5NULL\fP.
|
||||
Otherwise, the return value is either the newly inserted object
|
||||
or the matching object as noted.
|
||||
.PP
|
||||
.Ss " Void_t* dtdelete(Dt_t* dt, Void_t* obj)"
|
||||
If \f5obj\fP is \f5NULL\fP, methods \f5Dtstack\fP and \f5Dtqueue\fP
|
||||
delete respectively stack top or queue head while other methods do nothing.
|
||||
If \f5obj\fP is not \f5NULL\fP, an object matching \f5obj\fP is deleted.
|
||||
.Ss " Void_t* dtremove(Dt_t* dt, Void_t* obj)"
|
||||
When \f5obj\fP is not \f5NULL\fP, \f5dtdelete()\fP removes some object \fImatching\fP \f5obj\fP
|
||||
while \f5dtremove()\fP removes \f5obj\fP itself if it exists.
|
||||
When \f5obj\fP is \f5NULL\fP, if the method is \f5Dtstack\fP or \f5Dtqueue\fP
|
||||
then the stack top or queue head is respectively deleted.
|
||||
See \f5Dtdisc_t.freef\fP for object destruction.
|
||||
\f5dtdelete()\fP returns the deleted object (even if it was deallocated)
|
||||
or \f5NULL\fP on error.
|
||||
\f5dtdelete()\fP and \f5dtremove()\fP return the deleted object or \f5NULL\fP.
|
||||
.PP
|
||||
.Ss " Void_t* dtattach(Dt_t* dt, Void_t* obj)"
|
||||
This function is similar to \f5dtinsert()\fP but \f5obj\fP itself
|
||||
|
|
@ -469,13 +539,21 @@ from \f5dt\fP will not be freed (via the discipline \f5freef\fP function).
|
|||
.Ss " Void_t* dtmatch(Dt_t* dt, Void_t* key)"
|
||||
These functions find an object matching \f5obj\fP or \f5key\fP either from \f5dt\fP or
|
||||
from some dictionary accessible from \f5dt\fP via a viewpath (see \f5dtview()\fP.)
|
||||
\f5dtsearch()\fP and \f5dtmatch()\fP return the matching object or
|
||||
\f5NULL\fP on failure.
|
||||
The return value is the matching object or \f5NULL\fP.
|
||||
.PP
|
||||
.Ss " Void_t* dtfirst(Dt_t* dt)"
|
||||
.Ss " Void_t* dtnext(Dt_t* dt, Void_t* obj)"
|
||||
\f5dtfirst()\fP returns the first object in \f5dt\fP.
|
||||
\f5dtnext()\fP returns the object that follows an object matching \f5obj\fP.
|
||||
.Ss " Void_t* dtlast(Dt_t* dt)"
|
||||
.Ss " Void_t* dtprev(Dt_t* dt, Void_t* obj)"
|
||||
These functions assume some object ordering (more below) and can be used
|
||||
to iterate over all objects.
|
||||
\f5dtfirst()\fP returns the first object in \f5dt\fP or \f5NULL\fP if the
|
||||
dictionary is empty.
|
||||
\f5dtnext()\fP returns the object coming after \f5obj\fP
|
||||
or \f5NULL\fP if there is no such object.
|
||||
\f5dtlast()\fP and \f5dtprev()\fP are like \f5dtfirst()\fP and \f5dtnext()\fP
|
||||
but work in reverse order.
|
||||
|
||||
Objects are ordered based on the storage method in use.
|
||||
For \f5Dtoset\fP and \f5Dtobag\fP, objects are ordered by object comparisons.
|
||||
For \f5Dtstack\fP, objects are ordered in reverse order of insertion.
|
||||
|
|
@ -484,33 +562,47 @@ For \f5Dtlist\fP, objects are ordered by list position.
|
|||
For \f5Dtset\fP, \f5Dtbag\fP, \f5Dtrhset\fP and \f5Dtrhbag\fP,
|
||||
objects are ordered by some internal order defined at the time when these
|
||||
functions are called.
|
||||
In fact, both forward and reverse orders are defined to be the same
|
||||
for these methods.
|
||||
|
||||
Objects in a dictionary or a viewpath of dictionaries can be walked using
|
||||
\f5for(;;)\fP loops as below:
|
||||
|
||||
Objects in a dictionary or a viewpath can be walked using
|
||||
a \f5for(;;)\fP loop as below.
|
||||
.Cs
|
||||
for(obj = dtfirst(dt); obj; obj = dtnext(dt,obj))
|
||||
.Ce
|
||||
or
|
||||
.Cs
|
||||
for(obj = dtlast(dt); obj; obj = dtprev(dt,obj))
|
||||
.Ce
|
||||
|
||||
The argument \f5obj\fP of \f5dtnext()\fP or \f5dtprev()\fP is treated specially
|
||||
for a method that allows multiple equal elements such as \f5Dtobag\fP or \f5Dtbag\fP.
|
||||
If it is in the dictionary, then the returned object will be respectively
|
||||
immediately before or after it in the implicitly defined object ordering.
|
||||
If it is not in the dictionary but still matching a group of objects,
|
||||
then the returned object will be immediately after the last or before the first
|
||||
of the group respectively.
|
||||
.PP
|
||||
.Ss " Void_t* dtlast(Dt_t* dt)"
|
||||
.Ss " Void_t* dtprev(Dt_t* dt, Void_t* obj)"
|
||||
\f5dtlast()\fP and \f5dtprev()\fP are like \f5dtfirst()\fP and \f5dtnext()\fP
|
||||
but work in reverse order.
|
||||
For \f5Dtset\fP, \f5Dtbag\fP, \f5Dtrhset\fP and \f5Dtrhbag\fP,
|
||||
both reverse and forward orders are the same.
|
||||
Note that dictionaries on a viewpath are still walked in the order
|
||||
of the viewpath.
|
||||
.PP
|
||||
.Ss " Void_t* dtleast(Dt_t* dt, Void_t* obj)"
|
||||
.Ss " Void_t* dtmost(Dt_t* dt, Void_t* obj)"
|
||||
\f5dtleast()\fP returns the smallest object greater or equal to \f5obj\fP.
|
||||
\f5dtmost()\fP returns the largest object smaller or equal to \f5obj\fP.
|
||||
.Ss " Void_t* dtatleast(Dt_t* dt, Void_t* obj)"
|
||||
.Ss " Void_t* dtatmost(Dt_t* dt, Void_t* obj)"
|
||||
\f5dtatleast()\fP returns the smallest object greater or equal to \f5obj\fP.
|
||||
\f5dtatmost()\fP returns the largest object smaller or equal to \f5obj\fP.
|
||||
In addition, if there are multiple such objects in \f5dt\fP
|
||||
(i.e., when a bag method was used), then
|
||||
\f5dtatmost()\fP returns the first instance of such an object while
|
||||
\f5dtatleast()\fP returns the last one.
|
||||
Both functions return \f5NULL\fP if the desired object does not exist.
|
||||
|
||||
Again, object ordering depends on the storage method in use.
|
||||
For example, with \f5Dtoset\fP and \f5Dtobag\fP, the ordering of objects
|
||||
is well-defined and it is possible to call \f5dtleast()\fP or \f5dtmost()\fP
|
||||
With \f5Dtoset\fP and \f5Dtobag\fP, objects are linearly ordered by
|
||||
the discipline comparison function.
|
||||
As such, it is possible to call \f5dtatleast()\fP or \f5dtatmost()\fP
|
||||
on an object not in the dictionary and still get a meaningful result.
|
||||
On the other hand, with \f5Dtset\fP or \f5Dtrhset\fP, such a call will
|
||||
essentially be the same as \f5dtsearch()\fP because without matching
|
||||
an object, it cannot be determined what comes before or after.
|
||||
Storage methods other than \f5Dtoset\fP and \f5Dtobag\fP do not have
|
||||
an explicit ordering so \f5dtatmost()\fP
|
||||
and \f5dtatleast()\fP will return \f5NULL\fP when there are no matching objects.
|
||||
.PP
|
||||
.Ss " dtwalk(Dt_t* dt, int (*userf)(Dt_t*, Void_t*, Void_t*), Void_t* data)"
|
||||
This function calls \f5(*userf)(walk,obj,data)\fP on each object in \f5dt\fP and
|
||||
|
|
@ -528,6 +620,7 @@ to walk a single dictionary can incur significant cost due to function calls.
|
|||
For efficient walking of a single directory (i.e., no viewpathing),
|
||||
\f5dtflatten()\fP and \f5dtlink()\fP can be used.
|
||||
Objects in \f5dt\fP are made into a linked list and walked as follows:
|
||||
|
||||
.Cs
|
||||
for(link = dtflatten(dt); link; link = dtlink(dt,link) )
|
||||
.Ce
|
||||
|
|
@ -537,11 +630,48 @@ not \f5Void_t*\fP. That is, it returns a dictionary holder pointer,
|
|||
not a user object pointer
|
||||
(although both are the same if the discipline field \f5link\fP is zero.)
|
||||
The macro function \f5dtlink()\fP
|
||||
returns the dictionary holder object following \f5link\fP.
|
||||
The macro function \f5dtobj(dt,link)\fP
|
||||
returns the dictionary holder object following \f5link\fP and
|
||||
the macro function \f5dtobj(dt,link)\fP
|
||||
returns the user object associated with \f5link\fP,
|
||||
Beware that the flattened object list is unflattened on any
|
||||
dictionary operations other than \f5dtlink()\fP.
|
||||
Beware that a flattened object list is not guaranteed to maintain integrity
|
||||
if any dictionary operation other than \f5dtlink()\fP is performed
|
||||
(for example, this is important to watch out for
|
||||
if a dictionary is in \f5DT_SHARE\fP mode).
|
||||
.PP
|
||||
.Ss " Void_t* dtstart(Dt_t* dt, Void_t* obj);"
|
||||
This function starts a path for walking a dictionary.
|
||||
Note that such a path is restricted to \f5dt\fP only while disregarding
|
||||
all viewpath dictionaries (see \f5dtview()\fP).
|
||||
On success, a structure
|
||||
to be used in \f5dtstep()\fP for walking the path is returned.
|
||||
Otherwise, \f5NULL\fP is returned.
|
||||
|
||||
If \f5obj\fP is \f5NULL\fP, the path starts at the same object returned by \f5dtfirst()\fP.
|
||||
If \f5obj\fP is not \f5NULL\fP, it must match some object in the dictionary \f5dt\fP
|
||||
and the path will start there. No matching object will result in error.
|
||||
.PP
|
||||
.Ss " Void_t* dtstop(Dt_t* dt, Void_t* path);"
|
||||
This function ends a path and releases all memory source associated with it.
|
||||
.PP
|
||||
.Ss " Void_t* dtstep(Dt_t* dt, Void_t* path);"
|
||||
This function returns the object at current position in the given \f5path\fP.
|
||||
Successive calls move forward one object at a time in the same order that \f5dtnext()\fP
|
||||
does in the example \f5for(;;)\fP loop above. If there is no more object in the path,
|
||||
\f5dtstep()\fP returns \f5NULL\fP.
|
||||
|
||||
Below is a code fragment showing how to create and walk a path of objects.
|
||||
This object walking method is more restricted than the \f5dtfirst()/dtnext()\fP method
|
||||
since viewpathed dictionaries are ignored.
|
||||
However, it allows multiple paths to be traversed concurrently in the
|
||||
most efficient manner possible as supported by the underlying data structures.
|
||||
.Cs
|
||||
path = dtstart(dt, firstobj);
|
||||
for(obj = dtstep(dt, path); obj; obj = dtstep(dt,path))
|
||||
{
|
||||
...
|
||||
}
|
||||
dtstop(dt, path);
|
||||
.Ce
|
||||
.PP
|
||||
.Ss " Dtlink_t* dtextract(Dt_t* dt)"
|
||||
.Ss " Dtlink_t* dtrestore(Dt_t* dt, Dtlink_t* list)"
|
||||
|
|
@ -579,39 +709,232 @@ This has the number of objects in the dictionary.
|
|||
.Tp
|
||||
\f5ssize_t mlev\fP:
|
||||
This returns the maximum number of levels in the data structure used for object storage, i.e.,
|
||||
the binary tree or the recursive hash table.
|
||||
For a hash table with chaining (i.e., \f5Dtset\fP and \f5Dtbag\fP),
|
||||
the binary tree (e.g., \f5Dtoset\fP) or the recursive hash table based on a trie structure (e.g., \f5Dtrhset\fP).
|
||||
For a hash table with chaining (e.g., \f5Dtset\fP and \f5Dtbag\fP),
|
||||
it gives the length of the longest chain.
|
||||
.Tp
|
||||
\f5ssize_t lsize[]\fP:
|
||||
This gives the object counts at each level.
|
||||
For a hash table with chaining (i.e., \f5Dtset\fP and \f5Dtbag\fP),
|
||||
For a hash table with chaining (e.g., \f5Dtset\fP and \f5Dtbag\fP),
|
||||
a level is defined as objects at that position in their chains.
|
||||
Since chains can be arbitrarily long, the report is limited
|
||||
to objects at a level less than \f5DT_MAXSIZE\fP.
|
||||
The reported levels is limited to less than \f5DT_MAXSIZE\fP.
|
||||
.Tp
|
||||
\f5ssize_t tsize[]\fP:
|
||||
For a hash table using a trie structure, this counts the number of
|
||||
For a recursive hash table using a trie structure (\f5Dtrehash\fP), this counts the number of
|
||||
sub-tables at each level. For example, \f5tsize[0]\fP should be 1
|
||||
only for this hash table type.
|
||||
The reported levels is limited to less than \f5DT_MAXSIZE\fP.
|
||||
.Tp
|
||||
\f5char* mesg\fP:
|
||||
A summary message of some of the statistics.
|
||||
.PP
|
||||
.Ss "HASH FUNCTIONS"
|
||||
.PP
|
||||
.Ss " unsigned int dtcharhash(unsigned int h, char c)"
|
||||
.Ss " unsigned int dtstrhash(unsigned int h, char* str, int n)"
|
||||
These functions compute hash values from bytes or strings.
|
||||
\f5dtcharhash()\fP computes a new hash value from byte \f5c\fP and seed value \f5h\fP.
|
||||
\f5dtstrhash()\fP computes a new hash value from string \f5str\fP and seed value \f5h\fP.
|
||||
This function computes a new hash value from string \f5str\fP and seed value \f5h\fP.
|
||||
If \f5n\fP is positive, \f5str\fP is a byte array of length \f5n\fP;
|
||||
otherwise, \f5str\fP is a null-terminated string.
|
||||
.PP
|
||||
.SH CONCURRENCY PROGRAMMING NOTES
|
||||
Applications requiring concurrent accesses of a dictionary whether via separate threads
|
||||
or processes using shared memory should turn on shared mode for the dictionary.
|
||||
CDT uses locking and lockless data structures to
|
||||
provide safe concurrent accesses of objects.
|
||||
Much of this work is based on the atomic scalar operations available in \fIlibaso(3)\fP.
|
||||
|
||||
Even though CDT only considers objects
|
||||
via the attributes specified in a discipline structure,
|
||||
practical objects will often have many more attributes germane to the needs of an application.
|
||||
Thus, beyond safe concurrent dictionary operations, an application must also
|
||||
protect objects in concurrent computations outside of CDT.
|
||||
In particular, both \fIobject deletion\fP and \fIobject creation\fP should be handled with care.
|
||||
|
||||
The deletion case is relatively simple.
|
||||
No object should be destroyed as long as there is a reference to it.
|
||||
This guarantee is automatic when some garbage collection scheme is in place.
|
||||
Otherwise, some form of reference counting could be used to make sure
|
||||
that only objects with no reference would be deleted.
|
||||
An example to be given below discusses how reference counting could be
|
||||
done using the \f5DT_ANNOUNCE\fP feature of CDT to ensure correct timing
|
||||
for object deletion.
|
||||
|
||||
In general, object attributes should be well-defined before they are used.
|
||||
The simplest way to ensure this is to completely construct an object before
|
||||
before inserting it into a shared dictionary.
|
||||
However, an application using complex objects may try
|
||||
to avoid unnecessary construction work as follows.
|
||||
First, only a partial object with minimal information needed for dictionary operations
|
||||
is constructed.
|
||||
Then, either\f5dtinsert()\fP or \f5dtattach()\fP is called to insert this partial object
|
||||
into the dictionary. If the call returns this same object, then it was properly inserted and
|
||||
the rest of its attributes could then be filled in.
|
||||
If only a matching object is returned, then the new object is simply discarded.
|
||||
Although this object construction strategy works well in single-threaded code,
|
||||
it can cause references to uninitialized data in concurrent computations
|
||||
because objects are accessible by concurrent code
|
||||
as soon as \f5dtinsert()\fP or \f5dtattach()\fP returns.
|
||||
A way to solve this problem is to make sure that an incomplete object
|
||||
is completed before allowing any dictionary operation accessing such an object
|
||||
to return it to the application.
|
||||
|
||||
Both reference counting for safe objection deletion and ensuring readiness
|
||||
on object creation can be coordinate with CDT via the event \f5DT_ANNOUNCE\fP.
|
||||
An example of how to do this is given next.
|
||||
Objects are assumed to be of type \f5Obj_t\fP and have two
|
||||
fields: \f5ready\fP to indicate the readiness of an object
|
||||
and \f5refn\fP for reference counting.
|
||||
Both fields \f5ready\fP and \f5refn\fP are initialized to zero.
|
||||
Below are the relevant discipline functions \f5Dtdisc_t.eventf\fP
|
||||
and \f5Dtdisc_t.freef\fP to handle events and to free an object:
|
||||
|
||||
.Cs
|
||||
int eventf(Dt_t* dt, int type, Void_t* arg, Dtdisc_t* disc)
|
||||
{
|
||||
if(type & DT_ANNOUNCE)
|
||||
{
|
||||
if(!(type & DT_DELETE) )
|
||||
{
|
||||
Obj_t *obj = (Obj_t*)arg;
|
||||
|
||||
if(type & ~(DT_ANNOUNCE|DT_INSERT|DT_ATTACH))
|
||||
while(asogetchar(&obj->ready) == 0 )
|
||||
asorelax(1);
|
||||
|
||||
asoaddint(&obj->refn, 1);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
...
|
||||
}
|
||||
|
||||
void freef(Dt_t* dt, Void_t* arg, Dtdisc_t* disc)
|
||||
{
|
||||
Obj_t *obj = (Obj_t*)arg;
|
||||
|
||||
while(asogetchar(&obj->ready) == 0 )
|
||||
asorelax(1);
|
||||
|
||||
while(asogetint(&obj->refn) > 0 )
|
||||
asorelax(1);
|
||||
|
||||
... destroy the object ...
|
||||
}
|
||||
.Ce
|
||||
|
||||
Recall that each operation announcement is composed of \f5DT_ANNOUNCE\fP
|
||||
and some bits to indicate the operation itself.
|
||||
The test to exclude \f5dtdelete()\fP (indicated by the bit \f5DT_DELETE\fP)
|
||||
in \f5eventf()\fP is needed because an announcement always occurs
|
||||
right before the relevant
|
||||
CDT operation returns and, in the case of \f5dtdelete()\fP,
|
||||
the object may/will be already destroyed at that time.
|
||||
|
||||
The \f5while()\fP loops in both \f5eventf()\fP and \f5freef()\fP cause
|
||||
the relevant operations to wait until the object is \fIready\fP (i.e.,
|
||||
all of its attributes are constructed) before proceeding.
|
||||
The \f5asorelax(1)\fP call yields control of the processor for 1 nanosecond
|
||||
so other processes can do their work.
|
||||
Note that the test for \f5~(DT_ANNOUNCE|DT_INSERT|DT_ATTACH)\fP in \f5eventf()\fP
|
||||
means that the loop will execute for all CDT operations except for
|
||||
the \f5dtinsert()\fP or \f5dtattach()\fP call that actually inserts \f5obj\fP
|
||||
into the dictionary (more on this below).
|
||||
|
||||
When the \f5while\fP loop finished, the construction of object \f5obj\fP is known
|
||||
to be completed. \f5eventf()\fP increases the reference count \f5obj->refn\fP by one
|
||||
before the respective operation returns \f5obj\fP to the calling code.
|
||||
On the other hand, \f5freef()\fP waits for the reference
|
||||
count to reach zero before proceeding to destroy the object.
|
||||
Waiting for object readiness in \f5freef()\fP before object destruction is necessary
|
||||
to avoid any issues with deleting uninitialized data.
|
||||
Again, it should be emphasized that reference counting
|
||||
is needed only for a memory management model where objects can be freed
|
||||
regardless of whether or not there are any references to them.
|
||||
Applications that use some form of garbage collection in general or
|
||||
for dictionary objects may ignore doing reference counting as done in this example.
|
||||
|
||||
Next, consider a fragment of code to access
|
||||
objects concurrently from different threads or processes:
|
||||
|
||||
.Cs
|
||||
if((obj = dtmatch(dt, "key_string")) != NULL)
|
||||
{
|
||||
...process the object obj...
|
||||
|
||||
asosubint(&obj->refn, 1);
|
||||
dtdelete(dt, obj);
|
||||
}
|
||||
.Ce
|
||||
|
||||
The sequence of activities is as follows.
|
||||
First, the call \f5dtmatch()\fP retrieves an object \f5obj\fP.
|
||||
An announcement would be made during the call just before \f5obj\fP is returned
|
||||
causing the reference count of \f5obj\fP to be increased by one.
|
||||
After processing \f5obj\fP, the reference count is decreased by one using the
|
||||
atomic subtraction operator \f5asosubint()\fP.
|
||||
Then, \f5dtdelete()\fP is called to delete the object.
|
||||
|
||||
A possible danger is that concurrent calls to \f5dtdelete()\fP
|
||||
may end up causing the same memory to be freed more than once.
|
||||
Fortunately, this cannot happen.
|
||||
CDT guarantees that, of all the concurrent calls to \f5dtdelete()\fP on \f5obj\fP,
|
||||
only one will get far enough to make the \f5freef()\fP call while others do nothing.
|
||||
|
||||
Finally, consider a code fragment to construct and use the object \f5obj\fP:
|
||||
|
||||
.Cs
|
||||
... construct a partial object obj ...
|
||||
if((insobj = dtinsert(dt, obj)) == obj )
|
||||
{
|
||||
... fully construct obj ...
|
||||
asocaschar(&obj->ready, 0, 1);
|
||||
|
||||
... compute based on obj...
|
||||
asosubint(&obj->refn, 1);
|
||||
}
|
||||
else
|
||||
{ ... destroy the partial obj ...
|
||||
|
||||
... compute based on insobj...
|
||||
asosubint(&insobj->refn, 1);
|
||||
}
|
||||
.Ce
|
||||
|
||||
After the \f5dtinsert()\fP call returns,
|
||||
all other concurrent computations invoking dictionary operations to access \f5obj\fP
|
||||
will be blocked in the \f5eventf()\fP function until \f5obj->ready\fP is set to 1
|
||||
by the above \f5asocaschar()\fP call.
|
||||
As this is a concurrent computing application,
|
||||
the above code fragment itself can be
|
||||
executed in parallel with different but equivalent versions of \f5obj\fP.
|
||||
In that case, only one \f5dtinsert()\fP call will succeed in inserting a new object
|
||||
while the others will report a matching object, i.e., the one actually inserted.
|
||||
The announcement of the successful case is \f5DT_ANNOUNCE|DT_INSERT\fP
|
||||
while the announcement of the other cases is \f5DT_ANNOUNCE|DT_INSERT|DT_SEARCH\fP.
|
||||
The bit \f5DT_SEARCH\fP causes \f5eventf()\fP to
|
||||
to run the loop waiting for object completion. Thus, overall, except for the single case
|
||||
of a successful insertion of a new object, all other dictionary accesses that involve
|
||||
this object will return only when the object is ready.
|
||||
|
||||
Note that, for simplicity, the possibility of failure was ignored in the example.
|
||||
In both successful outcomes of \f5dtinsert()\fP, the reference count of an
|
||||
appropriate object will be increased by one. Thus, care must be taken to
|
||||
reduce that reference count for the object after it is no longer needed.
|
||||
Else, per this example implementation, a deletion of such an object will
|
||||
cause an infinite loop in the discipline \f5freef()\fP function.
|
||||
It is possible to implement a delayed object destruction scheme
|
||||
that avoids an infinite loop waiting for the reference count to drop to zero.
|
||||
However, a discussion of that is beyond the scope of this document.
|
||||
.PP
|
||||
.SH IMPLEMENTATION NOTES
|
||||
\f5Dtlist\fP, \f5Dtstack\fP and \f5Dtqueue\fP are based on doubly linked list.
|
||||
\f5Dtlist\fP, \f5Dtstack\fP, \f5Dtdeque\fP and \f5Dtqueue\fP are based on doubly linked list.
|
||||
\f5Dtoset\fP and \f5Dtobag\fP are based on top-down splay trees.
|
||||
\f5Dtset\fP and \f5Dtbag\fP are based on hash tables with
|
||||
move-to-front collision chains.
|
||||
\f5Dtset\fP and \f5Dtbag\fP are based on hash tables with collision chains.
|
||||
\f5Dtrhset\fP and \f5Dtrhbag\fP are based on a recursive hashing data structure
|
||||
that avoids table resizing.
|
||||
.PP
|
||||
.SH SEE ALSO
|
||||
libaso(3), libvmalloc(3)
|
||||
.PP
|
||||
.SH AUTHOR
|
||||
Kiem-Phong Vo, kpv@research.att.com
|
||||
|
|
|
|||
Loading…
Reference in a new issue