USER adaptor: localxml

This is the localxml user directory adaptor for the wftk. It encapsulates user directory functionality, storing users and groups as XML files in local directories. The directories in question are determined by the config module using the USER_DIRECTORY and GROUP_DIRECTORY named values.
#include <stdio.h>
#include <stdarg.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef WINDOWS
#include <io.h>
#include <errno.h>
#include "xmlapi.h"
#include "../wftk_internals.h"
The adaptor_info structure is used to pass adaptor info (duh) back to the config module when it's building an adaptor instance. Here's what it contains:
static char *names[] = 

XML * USER_localxml_init (WFTK_ADAPTOR * ad, va_list args);
XML * USER_localxml_free (WFTK_ADAPTOR * ad, va_list args);
XML * USER_localxml_info (WFTK_ADAPTOR * ad, va_list args);
XML * USER_localxml_get  (WFTK_ADAPTOR * ad, va_list args);
XML * USER_localxml_auth (WFTK_ADAPTOR * ad, va_list args);

static WFTK_API_FUNC vtab[] = 

static struct adaptor_info _USER_localxml_info =
Cool. So here's the incredibly complex function which returns a pointer to that:
struct adaptor_info * USER_localxml_get_info ()
   return & _USER_localxml_info;
Thus concludes the communication with the config module. Now on with the actual implementation of functionality.
XML * USER_localxml_init (WFTK_ADAPTOR * ad, va_list args) {
   struct stat statbuf;
   const char * parms;
   char directory[256];
   char * end;

   parms = xml_attrval (ad->parms, "parm");
   if (!*parms) parms = config_get_value (ad->session, "");

   /* Check for existence, return error if the directory doesn't exist or if it isn't a directory. */
   strcpy (directory, parms);
   end = directory + strlen (directory) - 1;
   if (*end == '\\') *end = '\0';
   if (*end == '/') *end = '\0';

   if (stat (directory, &statbuf) == -1) {
      xml_setf (ad->parms, "error", "Directory '%s' not found.", directory);
      return (XML *) 0;
   if (!(statbuf.st_mode & S_IFDIR)) {
      xml_setf (ad->parms, "error", "Directory '%s' not directory.", directory);
      return (XML *) 0;

   strcat (directory, "/");
   xml_set (ad->parms, "dir", directory);
   strcpy (directory, "localxml:");
   strcat (directory, xml_attrval (ad->parms, "dir"));
   xml_set (ad->parms, "spec", directory);
   return (XML *) 0;
That wasn't so hard, was it? Well, freeing up the adaptor is much easier:
XML * USER_localxml_free (WFTK_ADAPTOR * ad, va_list args) { return (XML *) 0; }
Next up is the info call, which builds and returns a little XML telling the caller about the adaptor. If the adaptor itself is NULL, then it just returns info about the installed adaptor handler; otherwise it's free to elaborate on the adaptor instance.
XML * USER_localxml_info (WFTK_ADAPTOR * ad, va_list args) {
   XML * info;

   info = xml_create ("info");
   xml_set (info, "type", "user");
   xml_set (info, "name", "localxml");
   xml_set (info, "ver", "1.0.0");
   xml_set (info, "compiled", __TIME__ " " __DATE__);
   xml_set (info, "author", "Michael Roberts");
   xml_set (info, "contact", "");
   xml_set (info, "extra_functions", "0");

   return (info);
We've got two functions in the user adaptor, one to retrieve a descriptive XML file (which will, at least at first, just be the user entry itself), and one to authenticate a password against a user. For the time being we're going to be really slipshod about that last, and just store the password in plaintext. Post-v1.0 (sigh) we'll want to at least encrypt the password or something. Or just switch to LDAP.
XML * USER_localxml_get (WFTK_ADAPTOR * ad, va_list args) {
   char path[256];
   char *id = (char *) 0;
   FILE *file;
   XML * ret;

   if (args) id = va_arg (args, char *);
   if (!id) {
      xml_set (ad->parms, "error", "No ID given.");
      return (XML *) 0;

   strcpy (path, xml_attrval (ad->parms, "dir"));
   strcat (path, id);
   strcat (path, ".xml");
   file = fopen (path, "r");
   if (!file) {
      xml_setf (ad->parms, "error", "Couldn't open file '%s' for reading.", path);
      return (XML *) 0;

   ret = xml_read (file);
   fclose (file);

   return ret;


XML * USER_localxml_auth (WFTK_ADAPTOR * ad, va_list args) {
   XML * user = 0;
   char * password;

   if (args) user = va_arg (args, XML *);
   if (!user) {
      xml_set (ad->parms, "error", "No user given.");
      return (XML *) 0;
   password = va_arg (args, char *);

   if (!strcmp (password, xml_attrval (user, "password"))) return user;
   return (XML *) 0;

This code and documentation are released under the terms of the GNU license. They are additionally copyright (c) 2000, Vivtek. All rights reserved except those explicitly granted under the terms of the GNU license. This presentation was prepared with LPML. Try literate programming. You'll like it.