[Mesa-dev] [PATCH] mesa: Drop PATH_MAX usage.

[Roland Mainz]

On Tue, Nov 15, 2016 at 9:56 PM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
> On 15 November 2016 at 20:04, Kenneth Graunke <kenneth at whitecape.org> wrote:
>> GNU/Hurd does not define PATH_MAX since it doesn't have such arbitrary
>> limitation, so this failed to compile.  Apparently glibc does not
>> enforce PATH_MAX restrictions anyway, so it's kind of a hoax:
>>
>> https://www.gnu.org/software/libc/manual/html_node/Limits-for-Files.html
>>
>> MSVC uses a different name (_MAX_PATH) as well, which is annoying.
>>
>> We don't really need it.  We can simply asprintf() the filenames.
>> If the filename exceeds an OS path limit, presumably fopen() will
>> fail, and we already check that.  (We actually use ralloc_asprintf
>> because Mesa provides that everywhere, and it doesn't look like we've
>> provided an implementation of GNU's asprintf() for all platforms.)
>>
>> Fixes the build on GNU/Hurd.
>>
>> Cc: "13.0" <mesa-stable at lists.freedesktop.org>
>> Signed-off-by: Samuel Thibault <samuel.thibault at ens-lyon.org>
>> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98632
>> ---
>>  src/mesa/main/arbprogram.c | 12 ++++--------
>>  src/mesa/main/shaderapi.c  | 37 +++++++++++--------------------------
>>  2 files changed, 15 insertions(+), 34 deletions(-)
>>
>> Samuel, does this fix the build for you?
>>
>> Emil, I didn't add the Fixes: tag because this was broken long before
>> that patch - MESA_SHADER_DUMP_PATH/MESA_SHADER_READ_PATH have existed
>> for a while now.
>>
> Ack, makes sense. I've only looked at the latest instance which
> introduces/uses the define.
>
> The patch is spot on afaict
> Reviewed-by: Emil Velikov <emil.velikov at collabora.com>

-- snip --
+   char *name = construct_name(stage, source, read_path);
    f = fopen(name, "r");
+   ralloc_free(name);
    if (!f)
       return NULL;
-- snip --

You don't need |errno|, right ? Most variants of |*free()| don't
preserve the |errno| value...

----

Bye,
Roland

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