[FFmpeg-devel] [PATCH] w32pthreads: add support for setting thread name

[Kacper Michajlow]

On Tue, 4 Mar 2025 at 15:50, James Almer <jamrial at gmail.com> wrote:
>
> On 3/4/2025 9:52 AM, Kacper Michajłow wrote:
> > Signed-off-by: Kacper Michajłow <kasper93 at gmail.com>
> > ---
> >   compat/w32pthreads.h | 30 ++++++++++++++++++++++++++++++
> >   libavutil/thread.h   |  2 ++
> >   2 files changed, 32 insertions(+)
> >
> > diff --git a/compat/w32pthreads.h b/compat/w32pthreads.h
> > index fd6428e29f..83b4819205 100644
> > --- a/compat/w32pthreads.h
> > +++ b/compat/w32pthreads.h
> > @@ -44,6 +44,7 @@
> >   #include "libavutil/internal.h"
> >   #include "libavutil/mem.h"
> >   #include "libavutil/time.h"
> > +#include "libavutil/wchar_filename.h"
> >
> >   typedef struct pthread_t {
> >       void *handle;
> > @@ -209,4 +210,33 @@ static inline int pthread_setcancelstate(int state, int *oldstate)
> >       return 0;
> >   }
> >
> > +static inline int win32_thread_setname(const char *name)
> > +{
> > +    typedef HRESULT (WINAPI *SetThreadDescriptionFn)(HANDLE, PCWSTR);
> > +    SetThreadDescriptionFn pSetThreadDescription;
> > +    HRESULT hr;
> > +    wchar_t *wname;
> > +
> > +#if !HAVE_UWP
> > +    HMODULE kernel32 = GetModuleHandleW(L"kernel32.dll");
> > +    if (!kernel32)
> > +        return ENOSYS;
> > +    pSetThreadDescription = (SetThreadDescriptionFn)
> > +        GetProcAddress(kernel32, "SetThreadDescription");
> > +    if (!pSetThreadDescription)
> > +        return ENOSYS;
> > +#else
> > +    WINBASEAPI HRESULT WINAPI
> > +    SetThreadDescription(HANDLE hThread, PCWSTR lpThreadDescription);
> > +    pSetThreadDescription = &SetThreadDescription;
> > +#endif
> > +
> > +    if (utf8towchar(name, &wname) < 0)
> > +        return ENOMEM;
> > +
> > +    hr = pSetThreadDescription(GetCurrentThread(), wname);
> > +    av_free(wname);
> > +    return SUCCEEDED(hr) ? 0 : EINVAL;
> > +}
> > +
> >   #endif /* COMPAT_W32PTHREADS_H */
> > diff --git a/libavutil/thread.h b/libavutil/thread.h
> > index 2c00c7cc35..d1a36a6772 100644
> > --- a/libavutil/thread.h
> > +++ b/libavutil/thread.h
> > @@ -229,6 +229,8 @@ static inline int ff_thread_setname(const char *name)
> >   #endif
> >   #elif HAVE_PTHREAD_SET_NAME_NP
> >       pthread_set_name_np(pthread_self(), name);
> > +#elif HAVE_W32THREADS
> > +    ret = AVERROR(win32_thread_setname(name));
>
> AVERROR(0) is probably not a good idea, so negate the codes in
> win32_thread_setname() directly.

Hmm, I can, but this is following the current pattern. All
`pthread_setname_np` calls above will return 0 on success and are
wrapped by AVERROR.