[PD-dev] the future of [declare] and canvas_savedeclarationsto()
Hans-Christoph Steiner
hans at eds.org
Fri May 23 23:56:09 CEST 2008
Yes, sure, that is possible. Then I would also have to do that in
libdir.c and any other place that relies on sys_libdir being an
absolute directory.
This will also make relative paths in [declare -stdpath] have
different behavior based on whether sys_libdir is relative or not.
If sys_libdir is absolute, then canvas_open() will use that path, if
sys_libdir is relative, then canvas_open() will append the parent
canvas' current dir. That's a bug with using realpath() prevents.
(which reminds me, I wrote a false comment in canvas_open(), "if not
absolute path, append Pd lib dir" should read "if not absolute path,
append parent canvas' current dir").
Also, I think that an API should provide a reliable interface that is
as simple as possible, yet no simpler. sys_libdir is part of the Pd
API, and insuring that it is _always_ absolute, rather than just
"almost always" absolute, is an important difference.
If you want, I'll re-write the realpath() section according to the
cert.org guidelines.
.hc
On May 23, 2008, at 9:23 PM, Miller Puckette wrote:
> So... I'm sure this is a dead end, but is there some way [import]
> could be written to invoke realpath() so Pd doesn't have to?
>
> cheers
> M
>
> On Fri, May 23, 2008 at 02:07:58AM +0200, Hans-Christoph Steiner
> wrote:
>>
>> If you really want to get into realpath():
>>
>> https://www.securecoding.cert.org/confluence/display/seccode/FIO02-A.
>> +Canonicalize+path+names+originating+from+untrusted+sources
>>
>> .hc
>>
>>> On May 22, 2008, at 10:06 PM, Hans-Christoph Steiner wrote:
>>>
>>>>
>>>> To quote the whole text:
>>>>
>>>> Avoid using this function. It is broken by design since (unless
>>>> using the non-
>>>> standard resolved_path == NULL feature) it is impossible to
>>>> determine a suitable
>>>> size for the output buffer, resolved_path. According to POSIX a
>>>> buffer of size
>>>> PATH_MAX suffices, but PATH_MAX need not be a defined constant,
>>>> and may have to
>>>> be obtained using pathconf(). And asking pathconf() does not
>>>> really help, since
>>>> on the one hand POSIX warns that the result of pathconf()
>>>> may be huge and
>>>> unsuitable for mallocing memory. And on the other hand pathconf
>>>> () may return -1
>>>> to signify that PATH_MAX is not bounded.
>>>>
>>>> I think whoever wrote that man page is really splitting hairs
>>>> there, the FreeBSD/Mac OS X man page has no complaints about it.
>>>> They are complaining that PATH_MAX _might_ not be defined. But on
>>>> GNU/Linux, MinGW, and FreeBSD/Mac OS X, FILENAME_MAX _is_
>>>> defined. So just use FILENAME_MAX to allocate the buffer that
>>>> realpath() uses (which was already happening anyway in s_main.c,
>>>> but with MAXPDSTRING instead). It's a widely implemented POSIX
>>>> function, how much more standard do you want? ;)
>>>>
>>>> I think that Pd should give reliable information in the publically
>>>> defined API (ok, s_stuff.h, but still). For example, it makes
>>>> life easier in a lot of ways if you can count on sys_libdir being
>>>> an absolute path, rather than making every other bit of code that
>>>> might every use a path that is based on sys_libdir check to make
>>>> sure that it is indeed absolute. The vast majority of the time,
>>>> sys_libdir is an absolute path, and AFAIK, on Windows it is always
>>>> an absolute path.
>>>>
>>>> .hc
>>>>
>>>>
>>>> On May 22, 2008, at 9:44 PM, Miller Puckette wrote:
>>>>
>>>>> I finally realized realpath() is a pre-existing function. (I
>>>>> imagined
>>>>> it was sitting in another source file that didn't make it to the
>>>>> patch)
>>>>>
>>>>> but.. "man realpath" says "Avoid using this function. It is
>>>>> broken by design..."
>>>>> so I'm sceptical of the idea. Anyway, why can't [import] just
>>>>> make the
>>>>> call if it needs it?
>>>>>
>>>>> cheers
>>>>> M
>>>>>
>>>>>
>>>>> On Thu, May 22, 2008 at 09:33:14PM +0200, Hans-Christoph Steiner
>>>>> wrote:
>>>>>>
>>>>>> The only real change to s_main.c in that path is the addition of
>>>>>> realpath(). It seems that the function there is just copying the
>>>>>> strings back and forth between sbuf and sbuf2, so I just added
>>>>>> one
>>>>>> more iteration of that back and forth for realpath().
>>>>>>
>>>>>> .hc
>>>>>>
>>>>>> On May 22, 2008, at 9:25 PM, Miller Puckette wrote:
>>>>>>
>>>>>>> I might have missed it, but I didn't see that realpath() itself
>>>>>>> made it into
>>>>>>> the patch... ?
>>>>>>>
>>>>>>> M
>>>>>>>
>>>>>>> On Thu, May 22, 2008 at 09:22:12PM +0200, Hans-Christoph Steiner
>>>>>>> wrote:
>>>>>>>>
>>>>>>>> The realpath() is definitely related. If you start Pd using a
>>>>>>>> relative path, like I do when doing dev work (e.g. make && ../
>>>>>>>> bin/
>>>>>>>> pd), then sys_libdir will be a relative path. That means it is
>>>>>>>> impossible to make absolute paths using sys_libdir, which is
>>>>>>>> what I
>>>>>>>> need to do to make [import] work, or loading libdirs with
>>>>>>>> [declare -
>>>>>>>> lib] and the libdir loader.
>>>>>>>>
>>>>>>>> I can't see any problems that realpath() might cause.
>>>>>>>>
>>>>>>>> .hc
>>>>>>>>
>>>>>>>> On May 22, 2008, at 8:45 PM, Miller Puckette wrote:
>>>>>>>>
>>>>>>>>> OK, I took most of the patch (not the "realpath()" call which
>>>>>>>>> seems
>>>>>>>>> unrelated) and uploaded to SVN, unless I'm mistaken.
>>>>>>>>>
>>>>>>>>> cheers
>>>>>>>>> Miller
>>>>>>>>>
>>>>>>>>> On Wed, May 21, 2008 at 08:22:23PM +0200, Hans-Christoph
>>>>>>>>> Steiner
>>>>>>>>> wrote:
>>>>>>>>>>
>>>>>>>>>> I was looking into this a bit more, and from what I can
>>>>>>>>>> tell, the
>>>>>>>>>> canvas-local path (ce_path) is always relative to the path
>>>>>>>>>> of the
>>>>>>>>>> parent patch. Here's the commit for pd-extended that adds
>>>>>>>>>> support
>>>>>>>>>> for absolute paths:
>>>>>>>>>>
>>>>>>>>>> http://pure-data.svn.sourceforge.net/viewvc/pure-data?
>>>>>>>>>> view=rev&revision=9862
>>>>>>>>>>
>>>>>>>>>> Also, I submitted a patch:
>>>>>>>>>>
>>>>>>>>>> http://sourceforge.net/tracker/index.php?
>>>>>>>>>> func=detail&aid=1917574&group_id=55736&atid=478072
>>>>>>>>>>
>>>>>>>>>> .hc
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On May 19, 2008, at 9:42 PM, Hans-Christoph Steiner wrote:
>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> I think I fixed the full paths bug, here's the commit:
>>>>>>>>>>>
>>>>>>>>>>> http://pure-data.svn.sourceforge.net/viewvc/pure-data?
>>>>>>>>>>> view=rev&revision=9856
>>>>>>>>>>>
>>>>>>>>>>> .hc
>>>>>>>>>>>
>>>>>>>>>>> On May 19, 2008, at 8:03 PM, Hans-Christoph Steiner wrote:
>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> I think this issue is pretty clear, and the languages that
>>>>>>>>>>>> I know
>>>>>>>>>>>> would fall along the lines of "each patch/abstraction has
>>>>>>>>>>>> its own
>>>>>>>>>>>> namespace" or in other words "#include only affects the
>>>>>>>>>>>> one .c
>>>>>>>>>>>> file", "import only affects the one .py file", etc. So I
>>>>>>>>>>>> agree
>>>>>>>>>>>> with Frank. Global settings are global, and canvas-local
>>>>>>>>>>>> settings
>>>>>>>>>>>> are local to the original file.
>>>>>>>>>>>>
>>>>>>>>>>>> The "semi-functional" part is the full paths that Marius
>>>>>>>>>>>> mentioned.
>>>>>>>>>>>>
>>>>>>>>>>>> Then the other question is how to use something like "#X
>>>>>>>>>>>> declare"/
>>>>>>>>>>>> canvas_savedeclarationsto() in externals. I'd like to
>>>>>>>>>>>> create an
>>>>>>>>>>>> [import] modelled after Python's import does, so I'd like
>>>>>>>>>>>> to use
>>>>>>>>>>>> "#X declare"/canvas_savedeclarationsto() with it.
>>>>>>>>>>>>
>>>>>>>>>>>> .hc
>>>>>>>>>>>>
>>>>>>>>>>>> On May 19, 2008, at 6:33 PM, Miller Puckette wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>> Hi all,
>>>>>>>>>>>>>
>>>>>>>>>>>>> I use 'declare' all the time.. don't think it's
>>>>>>>>>>>>> semifunctional at
>>>>>>>>>>>>> all.
>>>>>>>>>>>>> I think the questions about how declares should act inside
>>>>>>>>>>>>> abstractions
>>>>>>>>>>>>> are hard to resolve; in my own usage (and in the way I
>>>>>>>>>>>>> suggest
>>>>>>>>>>>>> others might
>>>>>>>>>>>>> want to use declare) it's always in the main patch, as a
>>>>>>>>>>>>> way to
>>>>>>>>>>>>> show the
>>>>>>>>>>>>> patch what libraries, etc, it needs.
>>>>>>>>>>>>>
>>>>>>>>>>>>> cheers
>>>>>>>>>>>>> Miller
>>>>>>>>>>>>>
>>>>>>>>>>>>> On Mon, May 19, 2008 at 06:28:31PM +0200, Hans-Christoph
>>>>>>>>>>>>> Steiner
>>>>>>>>>>>>> wrote:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Hey,
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> So I am diving into the whole canvas-local namespace and
>>>>>>>>>>>>>> [declare]
>>>>>>>>>>>>>> issue these days. I like the new "#X declare"/
>>>>>>>>>>>>>> canvas_savedeclarationsto() functionality, I think it
>>>>>>>>>>>>>> could be
>>>>>>>>>>>>>> useful
>>>>>>>>>>>>>> for a lot of things. I was thinking of making an API to
>>>>>>>>>>>>>> use
>>>>>>>>>>>>>> it in
>>>>>>>>>>>>>> externals, something like sys_register_loader(). I have
>>>>>>>>>>>>>> two
>>>>>>>>>>>>>> questions, first, how entrenched is the current
>>>>>>>>>>>>>> behavior of
>>>>>>>>>>>>>> [declare]? It currently is only semi-functional, and I
>>>>>>>>>>>>>> think few
>>>>>>>>>>>>>> people use it.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> The second is how to structure this for general use. I
>>>>>>>>>>>>>> have
>>>>>>>>>>>>>> thought
>>>>>>>>>>>>>> of two ways:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> - make "declare" the key word and allow other
>>>>>>>>>>>>>> objectclasses to
>>>>>>>>>>>>>> have
>>>>>>>>>>>>>> their own custom "#X declare" data.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> - allow objectclasses to register their own
>>>>>>>>>>>>>> declaration key
>>>>>>>>>>>>>> words,
>>>>>>>>>>>>>> like [import] could have "#X import".
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> The first would mean changing the behavior of [declare],
>>>>>>>>>>>>>> the
>>>>>>>>>>>>>> second
>>>>>>>>>>>>>> could lead to a big mess...
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> .hc
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> ---------------------------------------------------------
>>>>>>>>>>>>>> --
>>>>>>>>>>>>>> ----
>>>>>>>>>>>>>> --
>>>>>>>>>>>>>> --
>>>>>>>>>>>>>> -----
>>>>>>>>>>>>>> ----
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Man has survived hitherto because he was too ignorant to
>>>>>>>>>>>>>> know
>>>>>>>>>>>>>> how to
>>>>>>>>>>>>>> realize his wishes. Now that he can realize them, he
>>>>>>>>>>>>>> must
>>>>>>>>>>>>>> either
>>>>>>>>>>>>>> change them, or perish. -William Carlos Williams
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>>>> PD-dev mailing list
>>>>>>>>>>>>>> PD-dev at iem.at
>>>>>>>>>>>>>> http://lists.puredata.info/listinfo/pd-dev
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> -----------------------------------------------------------
>>>>>>>>>>>> --
>>>>>>>>>>>> ----
>>>>>>>>>>>> --
>>>>>>>>>>>> --
>>>>>>>>>>>> -------
>>>>>>>>>>>>
>>>>>>>>>>>> News is what people want to keep hidden and everything
>>>>>>>>>>>> else is
>>>>>>>>>>>> publicity. - Bill Moyers
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> ------------------------------------------------------------
>>>>>>>>>>> --
>>>>>>>>>>> ----
>>>>>>>>>>> --
>>>>>>>>>>> --
>>>>>>>>>>> ------
>>>>>>>>>>>
>>>>>>>>>>> You can't steal a gift. Bird gave the world his music, and
>>>>>>>>>>> if you
>>>>>>>>>>> can hear it, you can have it. - Dizzy Gillespie
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> -------------------------------------------------------------
>>>>>>>>>> --
>>>>>>>>>> ----
>>>>>>>>>> --
>>>>>>>>>> ---
>>>>>>>>>> ----
>>>>>>>>>>
>>>>>>>>>> News is what people want to keep hidden and everything
>>>>>>>>>> else is
>>>>>>>>>> publicity. - Bill Moyers
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> _______________________________________________
>>>>>>>>>> PD-dev mailing list
>>>>>>>>>> PD-dev at iem.at
>>>>>>>>>> http://lists.puredata.info/listinfo/pd-dev
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> ---------------------------------------------------------------
>>>>>>>> --
>>>>>>>> ----
>>>>>>>> ---
>>>>>>>> ----
>>>>>>>>
>>>>>>>> News is what people want to keep hidden and everything else is
>>>>>>>> publicity. - Bill Moyers
>>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> -----------------------------------------------------------------
>>>>>> --
>>>>>> -----
>>>>>> ----
>>>>>>
>>>>>> "It is convenient to imagine a power beyond us because that
>>>>>> means we
>>>>>> don't have to examine our own lives.", from "The Idols of
>>>>>> Environmentalism", by Curtis White
>>>>>>
>>>>>>
>>>>>>
>>>>
>>>>
>>>>
>>>> -------------------------------------------------------------------
>>>> --
>>>> -------
>>>>
>>>> If you are not part of the solution, you are part of the problem.
>>>>
>>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>> ---------------------------------------------------------------------
>> ---
>> ----
>>
>> You can't steal a gift. Bird gave the world his music, and if you can
>> hear it, you can have it. - Dizzy Gillespie
>>
>>
>>
>
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