common,w32: New function read_w32_reg_string.

* common/w32-reg.c (read_w32_reg_string): New.

* common/t-w32-reg.c (test_read_registry): Add another test.

common/t-w32-reg.c

@@ -44,25 +44,28 @@
 static void
 test_read_registry (void)
 {
-  char *string;
+  char *string1, *string2;
 
-#ifdef HAVE_W32CE_SYSTEM
-  string = read_w32_registry_string ("HKEY_CLASSES_ROOT",
-                                     "BOOTSTRAP\\CLSID", NULL);
-  if (!string)
-    fail (0);
-  fprintf (stderr, "Bootstrap clsid: %s\n", string);
-  xfree (string);
-#endif
-
-  string = read_w32_registry_string
+  string1 = read_w32_registry_string
     ("HKEY_CURRENT_USER",
      "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings",
      "User Agent");
-  if (!string)
+  if (!string1)
     fail (0);
-  fprintf (stderr, "User agent: %s\n", string);
-  xfree (string);
+  fprintf (stderr, "User agent: %s\n", string1);
+
+  string2 = read_w32_reg_string
+    ("HKCU\\Software\\Microsoft\\Windows\\CurrentVersion"
+     "\\Internet Settings:User Agent");
+  if (!string2)
+    fail (1);
+  fprintf (stderr, "User agent: %s\n", string2);
+  if (strcmp (string1, string2))
+    fail (2);
+
+
+  xfree (string1);
+  xfree (string2);
 }
 
 
@@ -71,10 +74,14 @@ test_read_registry (void)
 int
 main (int argc, char **argv)
 {
-  (void)argc;
-  (void)argv;
-
-  test_read_registry ();
+  if (argc > 1)
+    {
+      char *string = read_w32_reg_string (argv[1]);
+      printf ("%s -> %s\n", argv[1], string? string : "(null)");
+      xfree (string);
+    }
+  else
+    test_read_registry ();
 
   return 0;
 }

common/w32-reg.c

@@ -226,5 +226,53 @@ read_w32_registry_string (const char *root, const char *dir, const char *name)
 #endif /*!HAVE_W32CE_SYSTEM*/
 }
 
+/* Compact version of read_w32_registry_string.  This version expects
+ * a single string as key described here using an example:
+ *
+ *    HKCU\Software\GNU\GnuPG:HomeDir
+ *
+ * HKCU := the class, other supported classes are HKLM, HKCR, HKU, and
+ *         HKCC.  If no class is given and the string thus starts with
+ *         a backslash HKCU with a fallback to HKLM is used.
+ * Software\GNU\GnuPG := The actual key.
+ * HomeDir := the name of the item.  The name is optional to use the default
+ *            value.
+ *
+ * Note that the first backslash and the first colon act as delimiters.
+ *
+ * Returns a malloced string or NULL if not found.
+ */
+char *
+read_w32_reg_string (const char *key_arg)
+{
+  char *key;
+  char *p1, *p2;
+  char *result;
+
+  if (!key_arg)
+    return NULL;
+  key = xtrystrdup (key_arg);
+  if (!key)
+    {
+      log_info ("warning: malloc failed while reading registry key\n");
+      return NULL;
+    }
+
+  p1 = strchr (key, '\\');
+  if (!p1)
+    {
+      xfree (key);
+      return NULL;
+    }
+  *p1++ = 0;
+  p2 = strchr (p1, ':');
+  if (p2)
+    *p2++ = 0;
+
+  result = read_w32_registry_string (*key? key : NULL, p1, p2);
+  xfree (key);
+  return result;
+}
+
 
 #endif /*HAVE_W32_SYSTEM*/

common/w32help.h

@@ -44,6 +44,7 @@ char **w32_parse_commandline (char *cmdline, int globing, int *r_argv,
 /*-- w32-reg.c --*/
 char *read_w32_registry_string (const char *root,
 				const char *dir, const char *name );
+char *read_w32_reg_string (const char *key);
 
 /* Other stuff.  */
 #ifdef HAVE_W32CE_SYSTEM