This patch. although more convoluted than simple,
is likelier a better forward looking approach to
accessing metadata uniformly no matter what
the RPM_FOO_TYPE, or whether its a macro or a tag
or an array or lua or ....

    https://lists.dulug.duke.edu/pipermail/rpm-maint/2007-November/ 
000567.html

The patch is integrated (although largely untested
and unused other than as a means to popuate
RPMTAG_BUILDMACROS so far).

hth Happy hacking!

73 de Jeff

On Dec 27, 2007, at 10:43 AM, Jeff Johnson wrote:

> Multiple items like
>     Class: foo
>     Class: bar
> was the already implemented intent.
>
> (hysterical) The comma is treated as white space
> almost (just in case there is some weird corner
> case I fergit) everwhere identical to the more usual
> white space characters \0x20 \t \n through rpmbuild.
>
> Very b0rken and awkward when everyone's primary
> MUSTHAVE demand is "legacy compatibility".
>
> I dinna have the luxury of design wrto *.spec, feel free
> to add whatever additional hackery as you see fit. I'm
> all about bulldozing existing spec files by adding
> sparkly and glittery suger loaded syntax until everyone
> cries "Uncle!" many years now.
>
> 73 de Jeff
>
> On Dec 27, 2007, at 10:32 AM, Ralf S. Engelschall wrote:
>
>>   RPM Package Manager, CVS Repository
>>   http://rpm5.org/cvs/
>>    
>> _____________________________________________________________________ 
>> _______
>>
>>   Server: rpm5.org                         Name:   Ralf S.  
>> Engelschall
>>   Root:   /v/rpm/cvs                       Email:  rse@rpm5.org
>>   Module: rpm                              Date:   27-Dec-2007  
>> 16:32:32
>>   Branch: HEAD                             Handle: 2007122715323101
>>
>>   Modified files:
>>     rpm                     VENDOR
>>     rpm/build               parsePreamble.c
>>
>>   Log:
>>     - OpenPKG-specific change "make-class-available-as-macro":
>>       Do not treat "Class" tag as a fully arbitrary tag. In  
>> OpenPKG some
>>       .spec processing depends on the macro %{class} to be filled  
>> from
>>       the value of the "Class" tag, hence make sure it is not treated
>>       fully arbitrary (or else the macro would be not available). As
>>       %_arbitrary_tags restricts the allowed tags anyway, best  
>> would be to
>>       export also arbitrary tags as macros!
>>
>>     - OpenPKG-specific change "append-tag-value-to-macro"
>>       Instead of overwriting macro "foo" with the latest value  
>> "quux" in
>>       case of tag "Foo: bar" followed by tag "Foo: quux", set the  
>> macro
>>       "foo" to the comma-separated list "bar, quux". This allows  
>> one to get
>>       the values of all(!) tags instead of just the last one. In  
>> OpenPKG we
>>       use this to fetch the value of tags like BuildPreReq or  
>> NoSource.
>>
>>   Summary:
>>     Revision    Changes     Path
>>     2.20        +20 -0      rpm/VENDOR
>>     2.166       +17 -0      rpm/build/parsePreamble.c
>>    
>> _____________________________________________________________________ 
>> _______
>>
>>   patch -p0 <<'@@ .'
>>   Index: rpm/VENDOR
>>    
>> ===================================================================== 
>> =======
>>   $ cvs diff -u -r2.19 -r2.20 VENDOR
>>   --- rpm/VENDOR	25 Dec 2007 19:22:34 -0000	2.19
>>   +++ rpm/VENDOR	27 Dec 2007 15:32:31 -0000	2.20
>>   @@ -328,4 +328,24 @@
>>                         expanded macro text already terminates  
>> with a newline
>>         Reason:         Using e.g. rpm --eval "%{lua: print('foo\ 
>> \n') }" should
>>                         not lead to an extra trailing blank line.
>>   +      
>> _____________________________________________________________________ 
>> ___
>>   +
>>   +     Change:         make-class-available-as-macro
>>   +     Purpose:        Do not treat "Class" tag as a fully  
>> arbitrary tag.
>>   +     Reason:         In OpenPKG some .spec processing depends  
>> on the
>>   +                     macro %{class} to be filled from the value  
>> of the
>>   +                     "Class" tag, hence make sure it is not  
>> treated fully
>>   +                     arbitrary (or else the macro would be not  
>> available).
>>   +     Hint:           As %_arbitrary_tags restricts the allowed  
>> tags anyway,
>>   +                     best would be to export also arbitrary  
>> tags as macros!
>>   +      
>> _____________________________________________________________________ 
>> ___
>>   +
>>   +     Change:         append-tag-value-to-macro
>>   +     Purpose:        Instead of overwriting macro "foo" with  
>> the latest
>>   +                     value "quux" in case of tag "Foo: bar"  
>> followed
>>   +                     by tag "Foo: quux", set the macro "foo" to  
>> the
>>   +                     comma-separated list "bar, quux".
>>   +     Reason:         This allows one to get the values of all 
>> (!) tags
>>   +                     instead of just the last one. In OpenPKG  
>> we use this
>>   +                     to fetch the value of tags like  
>> BuildPreReq or NoSource.
>>
>>   @@ .
>>   patch -p0 <<'@@ .'
>>   Index: rpm/build/parsePreamble.c
>>    
>> ===================================================================== 
>> =======
>>   $ cvs diff -u -r2.165 -r2.166 parsePreamble.c
>>   --- rpm/build/parsePreamble.c	26 Dec 2007 09:36:35 -0000	2.165
>>   +++ rpm/build/parsePreamble.c	27 Dec 2007 15:32:32 -0000	2.166
>>   @@ -608,6 +608,9 @@
>>    	break;
>>        case RPMTAG_GROUP:
>>        case RPMTAG_SUMMARY:
>>   +#if defined(RPM_VENDOR_OPENPKG) /* make-class-available-as- 
>> macro */
>>   +    case RPMTAG_CLASS:
>>   +#endif
>>    	(void) stashSt(spec, pkg->header, tag, lang);
>>    	/*@fallthrough@*/
>>        case RPMTAG_DISTRIBUTION:
>>   @@ -807,7 +810,18 @@
>>        }
>>
>>        if (macro)
>>   +#if defined(RPM_VENDOR_OPENPKG) /* append-tag-value-to-macro */
>>   +    {
>>   +        char *value = rpmExpand("%{?", macro, ":%{", macro,  
>> "}, }", NULL);
>>   +        size_t value_len = strlen(value);
>>   +        value = xrealloc(value, value_len + strlen(field) + 1);
>>   +        strcpy(value+value_len, field);
>>   +        addMacro(spec->macros, macro, NULL, value, RMIL_SPEC);
>>   +        value = _free(value);
>>   +    }
>>   +#else
>>    	addMacro(spec->macros, macro, NULL, field, RMIL_SPEC);
>>   +#endif
>>
>>        return RPMRC_OK;
>>    }
>>   @@ -884,6 +898,9 @@
>>        {RPMTAG_KEYWORDS,		0, 0, "keywords"},
>>        {RPMTAG_KEYWORDS,		0, 0, "keyword"},
>>        {RPMTAG_BUILDPLATFORMS,	0, 0, "buildplatforms"},
>>   +#if defined(RPM_VENDOR_OPENPKG) /* make-class-available-as- 
>> macro */
>>   +    {RPMTAG_CLASS,		0, 0, "class"},
>>   +#endif
>>        /*@-nullassign@*/	/* LCL: can't add null annotation */
>>        {0, 0, 0, 0}
>>        /*@=nullassign@*/
>>   @@ .
>> _____________________________________________________________________ 
>> _
>> RPM Package Manager                                    http:// 
>> rpm5.org
>> CVS Sources Repository                                rpm- 
>> cvs@rpm5.org
>
> ______________________________________________________________________
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> Developer Communication List                        rpm-devel@rpm5.org