external/cde
1
0
Fork 0
mirror of git://git.code.sf.net/p/cdesktopenv/code synced 2025-03-09 15:50:02 +00:00
Code Issues Releases Wiki Activity

Refactor new b_hash(); better hash table clear (re: d8428a83)

Browse source 
The b_hash() function duplicated much of its code from b_alias(),
while b_alias() retained some code to support being called as
'hash'. There is no reason why 'hash' and 'alias' can't be handled
with a single function, as is the case several other builtins. Note
that option parsing can easily be made dependent on the name the
command was invoked with (in this case, argv[0]=='h').

The new hash builtin's -r option cleared the hash table by
assigning to PATH its existing value, triggering its associated
discipline function (put_restricted() in init.c) which then
actually cleared the hash table. That's a bit of a hack. It's nicer
if we can just do that directly. This requires taking a static
handler function rehash() from init.c, which invalidates one hash
table entry, and making it available to the builtin.

src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/include/builtins.h,
src/cmd/ksh93/include/nval.h,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/sh/name.c:
- Merge b_hash() into b_alias().
- The -x option was still uselessly setting the NV_EXPORT flag.
  Exported aliases were in ksh88 but were removed in ksh93.
- Rename rehash() handler function from init.c to nv_rehash
  (avoiding a possible conflict with another rehash() in cd_pwd.c)
  and move it to name.c just above nv_scan(), which it's meant to
  be used with. Make it an extern so typeset.c can use it.
- b_alias(): Replace the PATH assignment by an nv_scan() call to
  clear the hash table directly using the nv_rehash() handler.

src/cmd/ksh93/data/builtins.c:
- POSIX compliance fix: Remove BLT_SPC (special builtin) flag from
  "alias" definition. 'alias' is specified as a regular builtin.
- sh_optalias[]: Fix uninformative -t option documentation.
- sh_opthash[]: Edit for conciseness and clarity.

src/cmd/ksh93/sh.1:
- Edit the 'alias -t' and 'hash' documentation.
- Remove the -- prefix from the 'alias' entry, which indicated that
  it was supposed to be a declaration builtin like 'typeset', with
  assignment-arguments expanding tildes and not being subject to
  field splitting. However, my testing shows that 'alias' has never
  actually behaved that way on ksh93. Even adding the BLT_DCL flag
  in data/builtins.c doesn't seem to change that.

(cherry picked from commit afa68dca5c786daa13213973e8b0f9bf3a1dadf6)
This commit is contained in:
Martijn Dekker 2020-06-11 05:23:38 +02:00
parent 74b4162178
commit 80d9ae2b1c
8 changed files with 68 additions and 98 deletions
Download patch file Download diff file Expand all files Collapse all files

74
src/cmd/ksh93/bltins/typeset.c
View file

@ -133,56 +133,20 @@ int b_readonly(int argc,char *argv[],Shbltin_t *context)
return(setall(argv,flag,tdata.sh->var_tree, &tdata));
}
int b_hash(int argc,char *argv[],Shbltin_t *context)
{
register unsigned flag = NV_NOARRAY | NV_NOSCOPE | NV_ASSIGN | NV_TAGGED;
register Dt_t *troot;
register int rflag=0, n;
struct tdata tdata;
NOT_USED(argc);
memset((void *)&tdata, 0, sizeof(tdata));
tdata.sh = context->shp;
troot = tdata.sh->alias_tree;
/* The hash utility should not be recognized as the alias builtin */
tdata.aflag = '-';
while((n = optget(argv,sh_opthash))) switch(n)
{
case 'r':
rflag = 1;
break;
case ':':
error(2,"%s",opt_info.arg);
break;
case '?':
error(ERROR_usage(0),"%s",opt_info.arg);
return 2;
}
if (error_info.errors)
errormsg(SH_DICT,ERROR_usage(2),"%s",optusage(NULL));
argv += (opt_info.index-1);
/* Handle -r */
if (rflag)
{
Namval_t *np = nv_search((char *)PATHNOD, tdata.sh->var_tree, HASH_BUCKET);
nv_putval(np, nv_getval(np), NV_RDONLY);
}
troot = tdata.sh->track_tree;
/* We must fork in subshells to avoid polluting the parent shell's hash table. */
if(tdata.sh->subshell && !tdata.sh->subshare)
sh_subfork();
return setall(argv, flag, troot, &tdata);
}
/*
* 'alias' and 'hash' builtins
*/
#if 0
/* for the dictionary generator */
int b_hash(int argc,register char *argv[],Shbltin_t *context){}
#endif
int b_alias(int argc,register char *argv[],Shbltin_t *context)
{
register unsigned flag = NV_NOARRAY|NV_NOSCOPE|NV_ASSIGN;
register Dt_t *troot;
register int n;
register int rflag=0, n;
struct tdata tdata;
Namval_t *np;
NOT_USED(argc);
memset((void*)&tdata,0,sizeof(tdata));
tdata.sh = context->shp;
@ -196,7 +160,7 @@ int b_alias(int argc,register char *argv[],Shbltin_t *context)
*opt_info.option = 0;
tdata.argnum = 0;
tdata.aflag = *argv[1];
while((n = optget(argv,sh_optalias))) switch(n)
while((n = optget(argv, *argv[0]=='h' ? sh_opthash : sh_optalias))) switch(n)
{
case 'p':
tdata.prefix = argv[0];
@ -205,7 +169,10 @@ int b_alias(int argc,register char *argv[],Shbltin_t *context)
flag |= NV_TAGGED;
break;
case 'x':
flag |= NV_EXPORT;
/* obsolete, ignored */
break;
case 'r':
rflag=1;
break;
case ':':
errormsg(SH_DICT,2, "%s", opt_info.arg);
@ -217,11 +184,18 @@ int b_alias(int argc,register char *argv[],Shbltin_t *context)
if(error_info.errors)
errormsg(SH_DICT,ERROR_usage(2),"%s",optusage(NIL(char*)));
argv += (opt_info.index-1);
if(flag&NV_TAGGED)
troot = tdata.sh->track_tree;
}
if(context->shp->subshell && !context->shp->subshare)
/* fork a virtual subshell to avoid affecting parent shell's hash/alias table */
if((argv[1] || rflag) && tdata.sh->subshell && !tdata.sh->subshare)
sh_subfork();
/* 'alias -t', 'hash' */
if(flag&NV_TAGGED)
{
troot = tdata.sh->track_tree; /* use hash table */
tdata.aflag = '-'; /* make setall() treat 'hash' like 'alias -t' */
if(rflag) /* hash -r: clear hash table */
nv_scan(troot,nv_rehash,(void*)0,NV_TAGGED,NV_TAGGED);
}
return(setall(argv,flag,troot,&tdata));
}