Utilities cleanup

This is the final patch in a series mostly devoted to clean up of the
common library. After application of this patch pkicommon will be in
it's proposed form.

A large proportion of this patch is devoted to replacing the use of UNIX
shell commands to perform basic file system operations with built in
Perl functions. The other items in this patch are things which didn't
logically fit into any of the other patches.

The rationale for eschewing the use of shell commands where possible
is:

1) shell commands are OS specific, not all UN*X variants have the same
behavior.

2) shell commands are available only on UN*X variants.

3) the built in Perl functions are portable across most OS's

4) the built in Perl functions have better error handling and
reporting

5) the built in Perl functions are more efficient since they don't
need to spawn a shell to do one simple operation, instead they call
into the native OS library in the same process/thread.

6) the built in Perl functions are not subject to shell interpretation
thus making their use more robust. It's not unusual to have to
properly quote arguments when using a shell to protect against
unintended interpretation by the shell. Or worse to expose the
application to injection attacks where expanding a shell command
results in an untended operation performed with root privileges.

Also, many of the commands which used the Perl backtick operator to
perform a shell operation were not properly detecting if the command
failed. The backtick operator returns the stdout of the executed shell
command and discards stderr. The old code would capture the result of
the backtick operator (stdout), test to see if it was the empty string
and if so concluded the command succeeded. This is not correct, one
needs to check the exit status to determine success/failure. If an
error did occur the command probably wrote to stderr, but stderr is
discarded by the backtick operator. All this is documented in the patch
which added the run_command() utility.

For those routines for which there wasn't a Perl built-in equivalent
the code was changed to call run_command() instead of using the
backtick operator.

Each of the utility routines which creates/copies files/directories
had their parameter list expanded to accept optional specification of
the permission and ownership to be applied to the file system
object. This allows one call to replace multiple calls to utility
routines which ultimately makes the code in pkicreate smaller, less
verbose, easier to read and more robust.

The code used to parse an initscript was removed
(extract_chkconfig_parameters_from_start_stop_script()), it wasn't
called and I'm at a loss for why this would have been needed in the
first place. Also the parametrization of the start/stop positions is
changing as we move closer to LSB. The global variable
chkconfig_fields was also removed. It was only used in the routine
extract_chkconfig_parameters_from_start_stop_script(). What's up with
these global variables which should be private to the subroutine
utilizing them?

Many routines had logging added to them for tracing purposes. A call
to emit() with the subroutine name and parameters.

Many routines had the dry run check added to them. If $dry_run is true
they emit their tracing information and then return success.

Many routines had calls to add_install_info() added to them. This is
used to record the installation actions being performed.

Code that formerly had used shell commands to operate recursively on
directories now instead iterate over the contents of the directories
invoking our utilities, this allows us to use our primitives which
record the installation action. For example rather than
copy_directory() doing a "cp -r src dst" we walk the tree and invoke
our own create_directory() and copy_file() routines which are
responsible for recording the operation and doing such things as
setting permissions and ownership.

Comments referencing arg0, arg1, etc. were removed or edited (see
previous patch for parameter list clean up for an explanation).

Some functions were renamed to better reflect their actual operation
as would be understood by a system administrator.
e.g. give_file_to() became set_owner_group(), give_directory_to()
became set_owner_group_on_directory_contents().

A utility called set_permissions() was added as well as a utility
called set_file_props() which sets permissions and ownership with a
single call.

The routines move_file() and move_directory() were removed. They were
using the deprecated shell methodology but were never called by any
code. Rather than re-implement them I just removed them, if we need
these again in the future we can add them back with the preferred Perl
methodology.

A potential bug was fixed in copy_directory(). The logic used to
enumerate the set of destination directories which needed to be
created had a logic flaw. If a source directory was empty it wouldn't
get created in the destination. This occurred because the previous
logic was to enumerate all the source files to be copied and generate
a set of directories from those, but if a directory was empty it
wouldn't show up in the file list. The new logic is to independently
enumerate both directories and files in the src tree, this makes the
directory list complete.

Add utility to return the initscript name, get_registry_initscript_name().


git-svn-id: svn+ssh://svn.fedorahosted.org/svn/pki/trunk@1545 c9f7a03b-bd48-0410-a16d-cbbf54688b0b

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