Re: PATCH: Add type_sprint() function to return type in string form

[Andrew Cagney <ac131313@redhat.com>]

> On Fri, Apr 18, 2003 at 03:24:26PM -0700, Jason Molenda wrote:
> 
>> There are a few places in gdb where code prints an error message
>> with a type included in it.  The only way for these functions to
>> print a type is with type_print(), which takes a ui_file stream to
>> print its output to.  This means they either have to send the output
>> to gdb_stderr, or build up a fake memory ui_file and retrieve the
>> contents.
>> 
>> This patch adds a type_sprint() which does the latter and returns the
>> xmalloc()'ed string.

Good interface choice!  Just some tweaks.

sprint makes me think of the nasty sprintf family, which this is 
definitly not.  So ..  suggest calling it something like type_xstrdup: 
x-> xmalloc family; strdup -> allocate a string duplicate (like 
ui_file_xstrdup, but yes pushing it a bit).  The alternative would be 
type_xasprint (&string, ...) but I think that is getting ugly :-)

The old error message should never have included a period ("."), might 
as well remove it while tweaking the code.

>> The current code gives bogus data to an MI client.  We had a bug that
>> gave this output at Apple:
>> 
>> -> 64-var-list-children "var7" 2
>> <- 64^error,msg="."
>> -> 65-exec-status
>> <- (gdb) 
>> <- &"Type TWindow has no component named TWindow"
>> <- 65^done,status="stopped"
>> 
>> This happens because this particular error reporter looked like this:

Ulgh.  Testcase tweak?

>>   fprintf_unfiltered (gdb_stderr, "Type ");
>>   type_print (type, "", gdb_stderr, -1);
>>   fprintf_unfiltered (gdb_stderr, " has no component named ");
>>   fputs_filtered (name, gdb_stderr);
>>   error (".");
>> 
>> Similar code shows up in a few places, so it made sense to create a 
>> single function to format a type into a string and return the string.
>> 
>> I can drop the ada-lang.c part of the patch if that will complicate
>> the approval, but given that this code is clearly derived from
>> gdbtypes.c, I don't think the change is particularly controversial.
>> 
>> This patch adds no new testsuite failures on RHL7.1 (gcc 2.96, stabs).
> 
> 
> I think this is OK.  Sit on it for another day or two and check it in
> if no one objects in that time, please.

yup.  For ada, a best guess is sufficient.

Andrew


>> 2003-04-18  Jason Molenda  (jmolenda @ apple.com)
>> 
>>         * typeprint.c (type_sprint): New function to return string form
>>         of types.  Use as type_print, sans a stream.
>>         * value.h (type_sprint): Add prototype.
>>         * ada-lang.c (ada_lookup_struct_elt_type): Use type_sprint() when
>>         building error message.
>>         * gdbtypes.c (lookup_struct_elt_type): Ditto.
>>         * varobj.c (varobj_get_type): Use type_sprint() to get the type
>>         in a string form.
> 
> 
> 
> -- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer