34350, 34353: document zsh/db/gdbm module, clean up a few things in the code

Still core dumps at this revision if the tied parameter is forced to be a local and is not untied before end of scope.

ChangeLog

@@ -38,6 +38,13 @@
 	* 34368: Completion/Zsh/Command/_zstyle: _zstyle vcs_info
 	completion: Add missing styles
 
+2015-01-24  Barton E. Schaefer  <schaefer@zsh.org>
+
+	* 34350, 34353: Doc/Makefile.in, Doc/Zsh/mod_db_gdbm.yo,
+	Src/Modules/db_gdbm.c: document zsh/db/gdbm module, clean up a few
+	things in the code.  Still core dumps if the tied parameter is
+	forced to be a local and is not untied before end of scope.
+
 2015-01-23  Jun-ichi Takimoto <takimoto-j@kba.biglobe.ne.jp>
 
 	* 34335: _yum: fix bugs in _yum_all_pkgs

Doc/Makefile.in

@@ -60,7 +60,7 @@ MODDOCSRC = \
 Zsh/mod_attr.yo Zsh/mod_cap.yo Zsh/mod_clone.yo \
 Zsh/mod_compctl.yo Zsh/mod_complete.yo Zsh/mod_complist.yo \
 Zsh/mod_computil.yo Zsh/mod_curses.yo \
-Zsh/mod_datetime.yo Zsh/mod_deltochar.yo \
+Zsh/mod_datetime.yo Zsh/mod_db_gdbm.yo Zsh/mod_deltochar.yo \
 Zsh/mod_example.yo Zsh/mod_files.yo Zsh/mod_langinfo.yo \
 Zsh/mod_mapfile.yo Zsh/mod_mathfunc.yo Zsh/mod_newuser.yo \
 Zsh/mod_parameter.yo Zsh/mod_pcre.yo Zsh/mod_regex.yo \

Doc/Zsh/mod_db_gdbm.yo

@@ -0,0 +1,27 @@
+COMMENT(!MOD!zsh/db/gdbm
+Builtins for managing associative array parameters tied to GDBM databases.
+!MOD!)
+The tt(zsh/db/gdbm) module is used to create "tied" associative arrays
+that interface to database files.  If the GDBM interface is not available,
+the builtins defined by this module will report an error.  This module is
+also intended as a prototype for creating additional database interfaces,
+so the tt(ztie) builtin may move to a more generic module in the future.
+
+The builtins in this module are:
+
+startitem()
+findex(ztie)
+cindex(tied array, creating)
+item(tt(ztie -d db/gdbm -f) var(filename) var(arrayname))(
+Open the GDBM database identified by var(filename) and, if successful,
+create the associative array var(arrayname) linked to the file.  Note
+that var(arrayname) must be unset at the time tt(ztie) is called, and
+is always created as a global parameter (as if with `tt(typeset -g)').
+)
+findex(zuntie)
+cindex(tied array, destroying)
+item(tt(zuntie) var(arrayname) ...)(
+Close the GDBM database associated with each var(arrayname) and then
+unset the variable.
+)
+enditem()

Src/Modules/db_gdbm.c

@@ -39,9 +39,7 @@
 
 #include <gdbm.h>
 
-#if 0 /* what is this for? */
 static char *backtype = "db/gdbm";
-#endif
 
 static const struct gsu_scalar gdbm_gsu =
 { gdbmgetfn, gdbmsetfn, gdbmunsetfn };
@@ -60,33 +58,38 @@ bin_ztie(char *nam, char **args, Options ops, UNUSED(int func))
     Param tied_param;
 
     if(!OPT_ISSET(ops,'d')) {
-        zwarnnam(nam, "you must pass `-d db/gdbm' to ztie", NULL);
+        zwarnnam(nam, "you must pass `-d %s'", backtype);
 	return 1;
     }
     if(!OPT_ISSET(ops,'f')) {
-        zwarnnam(nam, "you must pass `-f' with a filename to ztie", NULL);
+        zwarnnam(nam, "you must pass `-f' with a filename", NULL);
 	return 1;
     }
 
     /* Here should be a lookup of the backend type against
      * a registry.
      */
+    if (strcmp(OPT_ARG(ops, 'd'), backtype) != 0) {
+        zwarnnam(nam, "unsupported backend type `%s'", OPT_ARG(ops, 'd'));
+	return 1;
+    }
 
     pmname = ztrdup(*args);
 
     resource_name = OPT_ARG(ops, 'f');
 
-    if (!(tied_param = createspecialhash(pmname, &getgdbmnode, &scangdbmkeys, 0))) {
-        zwarnnam(nam, "cannot create the requested parameter name", NULL);
-	return 1;
-    }
-
     dbf = gdbm_open(resource_name, 0, GDBM_WRCREAT | GDBM_SYNC, 0666, 0);
     if(!dbf) {
         zwarnnam(nam, "error opening database file %s", resource_name);
 	return 1;
     }
 
+    if (!(tied_param = createspecialhash(pmname, &getgdbmnode, &scangdbmkeys, 0))) {
+        zwarnnam(nam, "cannot create the requested parameter %s", pmname);
+	gdbm_close(dbf);
+	return 1;
+    }
+
     tied_param->u.hash->tmpdata = (void *)dbf;
 
     return 0;
@@ -98,19 +101,25 @@ bin_zuntie(char *nam, char **args, Options ops, UNUSED(int func))
 {
     Param pm;
     GDBM_FILE dbf;
+    char *pmname;
+    int ret = 0;
 
-    pm = (Param) paramtab->getnode(paramtab, args[0]);
-    if(!pm) {
-        zwarnnam(nam, "cannot untie %s", args[0]);
-	return 1;
+    for (pmname = *args; *args++; pmname = *args) {
+	pm = (Param) paramtab->getnode(paramtab, pmname);
+	if(!pm) {
+	    zwarnnam(nam, "cannot untie %s", pmname);
+	    ret = 1;
+	    continue;
+	}
+
+	dbf = (GDBM_FILE)(pm->u.hash->tmpdata);
+	gdbm_close(dbf);
+	/* free(pm->u.hash->tmpdata); */
+	pm->u.hash->tmpdata = NULL;
+	paramtab->removenode(paramtab, pm->node.nam);
     }
 
-    dbf = (GDBM_FILE)(pm->u.hash->tmpdata);
-    gdbm_close(dbf);
-/*    free(pm->u.hash->tmpdata); */
-    paramtab->removenode(paramtab, pm->node.nam);
-
-    return 0;
+    return ret;
 }
 
 /**/