[FFmpeg-devel] [PATCH v17 4/5] libavformat: Remove MAX_PATH limit and use UTF-8 version of getenv()

[Martin Storsjö]

On Sun, 19 Jun 2022, Martin Storsjö wrote:

> On Fri, 17 Jun 2022, Nil Admirari wrote:
>
>> 1. getenv() is replaced with getenv_utf8() across libavformat.
>> 2. New versions of AviSynth+ are now called with UTF-8 filenames.
>> 3. Old versions of AviSynth are still using ANSI strings,
>>   but MAX_PATH limit on filename is removed.
>> ---
>> libavformat/avisynth.c    | 39 +++++++++++++++++++++++++++------------
>> libavformat/http.c        | 20 +++++++++++++-------
>> libavformat/ipfsgateway.c | 35 +++++++++++++++++++++++------------
>> libavformat/tls.c         | 11 +++++++++--
>> 4 files changed, 72 insertions(+), 33 deletions(-)
>> 
>> diff --git a/libavformat/http.c b/libavformat/http.c
>> index c8f3f4b6a3..d90117e422 100644
>> --- a/libavformat/http.c
>> +++ b/libavformat/http.c
>> @@ -29,6 +29,7 @@
>> #include "libavutil/avassert.h"
>> #include "libavutil/avstring.h"
>> #include "libavutil/bprint.h"
>> +#include "libavutil/getenv_utf8.h"
>> #include "libavutil/opt.h"
>> #include "libavutil/time.h"
>> #include "libavutil/parseutils.h"
>
> This actually causes some surprise breakage in MSVC builds. Here, 
> getenv_utf8.h includes windows.h. If including windows.h and winsock2 headers 
> in the same file, the winsock2 headers must be included before.
>
> I fixed it locally by moving this new include down, with a comment like this:
>
> /* This header can include <windows.h>. That header has to be included after
> * winsock2 headers (included by network.h and os_support.h above). */
> #include "libavutil/getenv_utf8.h"
>
> (I had to do the same fixup in http.c and ipfsgateway.c.)

Alternatively, as these env variables mostly are used for host names to a 
proxy or similar, there's probably not much need for handling anything 
outside of ASCII anyway, so we could also consider just leaving these as 
plain getenv().

// Martin