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From: dgreen@hilo.cs.ucla.edu (Dan R. Greening)
Newsgroups: comp.windows.x
Subject: Bug in Storing non-String types to a resource database?
Message-ID: <1991May20.192203.8525@cs.ucla.edu>
Date: 20 May 91 19:22:03 GMT
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In digging around X11R4/mit/lib/X/Xrm.c, trying to figure out what the
resource database does when someone wants to write a non-String typed
entry to a file, I came across this piece of code:

[if a string then do something]

    } else {
        (void) fprintf(stream, "!%s:\t", XrmRepresentationToString(type));
        for (i = 0; i < value->size; i++)
            (void) fprintf(stream, "%02x", (int) value->addr[i]);
        if (index(value->addr, '\n')) {
           (void) fprintf(stream, ":\t\\\n");
           for (i = 0; value->addr[i]; i++) {
               if (value->addr[i] == '\n') {
                   (void) fprintf(stream, "\\n");
                   if (value->addr[i+1]) (void) fprintf(stream, "\\");
                   (void) fprintf(stream, "\n");
               } else {
                   (void) putc(value->addr[i], stream);
               }
            }
           }
        } else {
           (void) fprintf(stream, ":\t%s\n", value->addr);
        }

Basically, I think this is probably a bug that nobody has encountered yet.
It looks like when a non String-type entry is found, it is written out as

  <resource-name>"!"<resource-type>":	"<hex-representation-for-resource>
  <string-representation-for-resource-including-nulls>

Which is pretty weird.  The fix is easy, just replace it with

    } else {
        (void) fprintf(stream, "!%s:\t", XrmRepresentationToString(type));
        for (i = 0; i < value->size; i++)
            (void) fprintf(stream, "%02x", (int) value->addr[i]);
	(void) fprintf(stream, "\n");
	}

Unfortunately, though one can write out non-String values to a resource file,
you can't read them back in!  Since PutLineResources uses this to
insert the line:

        XrmQPutResource(pdb, bindings, quarks, XrmQString, &value);

Clearly, no fix to allow reading of non-String resources will be made to 
X11R4.  It does seem apparent to me that the resource database routines
were intended to handle non-String values (by the simple reason that there is 
a "type" field in all the Put/Get calls to the resource manager), but these 
were never fully implemented.  Will this be in X11R5?  (plead, plead).

I could very happily make use of them.
-- 
____
\  /Dan Greening	Software Transformation	  1601 Saratoga-Sunnyvale Rd
 \/ dgreen@cs.ucla.edu	(408) 973-8081 x313	  Cupertino, CA 95014