Migrating external sources using rpmlib from 4.0 -> 4.1+

[Nicholas Wourms <nwourms myrealbox com>]

Hi,

For awhile now, I've been using a neat little program from slackware[1], 
called getrpmtype, in a few of my shell scripts.  The program itself 
determines the package type and what version (Major & Minor) of rpm was 
used to make it.  I've had problems with "file" in the past returning 
inaccurate results, so I really do prefer to use this little utility 
instead.  The problem is that it uses the function rpmReadPackageHeader 
to obtain the attributes of the rpm, which seems to have gone missing in 
newer versions of rpm >= 4.1.  I'm not quite sure what provides 
equivalent functionality in rpm >= 4.1 and maximum rpm has not yet been 
updated to reflect the changes in the ABI.  I guess my question is: 
What is the new way to obtain src/bin type and major/minor information 
for a package?  Anyhow, if anyone has any suggestions, here's a snippet 
of routine used to open and parse the header of the rpm (note that I 
left out the command line parsing stuff, so argv[i] is just the name of 
the rpm(s) passed at the command line):

...
int c;
int i, e, src, major, minor;
Header h;
FD_t fd;
...
/* open */
if( (fd=fdOpen(argv[i], O_RDONLY, 0644)) == NULL ) {
  fprintf( stderr, "ERROR: Cannot open %s\n", argv[i] );
  continue;
}
...
/* parse header */
if( (e = rpmReadPackageHeader(fd, &h, &src, &major, &minor)) ) {
  fprintf( stderr, "rpmReadPackageHeader Error: %d\n%s\n",
           e, strerror(errno) );
}
...
/* print type */
if ( src ) {
  printf( "RPM v%d.%d source package.\n", major, minor );
} else {
  printf( "RPM v%d.%d binary package.\n", major, minor );
}
...

As a side note, why not provide compatibility wrapper functions so that 
the new rpm won't break existing source compatibility?

Cheers,
Nicholas

[1]: 
http://distro.ibiblio.org/pub/Linux/distributions/slackware/slackware-current/source/a/bin/getrpmtype.tar.gz