RFR:8060449:Proper error messages for newly obsolete command line flags.

[Daniel D. Daugherty]

On 11/7/14 12:13 PM, Max Ockner wrote:
> ID: 8060449
> webrev: http://cr.openjdk.java.net/~coleenp/8060449/

src/share/vm/runtime/arguments.cpp

     line 336: ) {
         This fragment is on a line by itself and far left.
         Minimally, it should align like this:

         line 331:     if (...
         line 336:        ) {

     However, I recommend a slightly different structure to
     this logic:

     size_t f_len = strlen(flag_status.name);
     size_t s_len = strlen(s);
     if (f_len == s_len || (f_len + 1) == s_len) {
       // this flag is the right length for a possible match
       if (strncmp(flag_status.name, s, f_len) == 0) ||
           ((s[0] == '+' || s[0] == '-') &&
            strncmp(flag_status.name, &s[1], f_len) == 0)) {
         // this flag is an exact match
         if (JDK_Version::current().compare(flag_status.accept_until) == 
-1) {
         ...
         }
       }
     }
     i++;

I have no idea if the above formatting is going to be
preserved by e-mail clients...

Dan


>
> Summary: A "newly obsolete" command line option is one which is no 
> longer supported, but still is acknowledged. There is a list of these 
> in arguments.cpp.
> It used to be that only a fixed number of characters were checked when 
> comparing a given command line option to the list of obsolete flags 
> (strncmp was used, where the number of characters to check is equal to 
> the length of the flag name from the table.)
> As a result, an arbitrary string appended to the end of an obsolete 
> argument goes unnoticed.
> This issue is fixed by comparing the lengths of the given flag and the 
> flags from the obsolete flags table.
> When a misspelled flag is fuzzy-matched to an obsolete flag, an 
> appropriate warning is given to save the user a few key strokes: (1) 
> unrecognized option [bad option]. (2) Did you mean [option]? (3) 
> [option] is obsolete as of [version])
>
> A new test for this feature checks for the presence of all three 
> components of the above error message.
>
> Tested with: vm.quick.testlist
>              hotspot jtreg tests
>              jprt
>
> Thanks for your help!
> Max Ockner
>
>