[bitbake-devel] [PATCH 1/3] fetcher: quote filenames given in commands

[Enrico Scholz]

Richard Purdie <richard.purdie at linuxfoundation.org> writes:

>> Filenames were given as-is to shell commands. This causes problems
>> when names contain characters which have a special meaning. 
> ...
> Whilst I understand what you're trying to fix, I'm afraid I don't like
> the patch. I'd prefer to have one way of building these commands, rather
> than two different ones with the shell=isinstance(cmd, basestring)
> check.

ok; one way would be calling of 'pipes.quote()' on every variable
substituting %s.  But that's boring, error prone and makes the code
ugly.

Another way might be to declare every command as a sequence with special
objects for shell operations; e.g.

| class ShellOp:
|     def __init__(self, op):
|         self.op = op
| 
| cmd = ['bunzip2', '-d', file, ShellOp('|'), 'tar', 'xf', '-']

In simple case (no ShellOp objects), sequence will be given directly to
Popen() with shell=False. Else, pipes.quote() will be applied on every
string element of the sequence while ShellOp() objects will be kept as
as-is.


> I'd like to find a cleaner approach that doesn't involve runfetchcmd2.

As I wrote in the comment, runfetchcmd2() exists because ${FETCHCMD}
might be defined as

  git -c 'url.file://${WORKSPACE_DIR}/avrprog.insteadOf=git://git.somewhere/avrprog.git'

There is no simple way to split it into a sequence (note: there might be
quoted whitespaces in an option).



Enrico