On Tue, 12 Nov 2019 16:16:39 +0100, Arnd Bergmann wrote:
From: Baolin Wang baolin.wang@linaro.org
The struct snd_rawmidi_status will use 'timespec' type variables to record timestamp, which is not year 2038 safe on 32bits system.
Thus we introduced 'struct snd_rawmidi_status32' and 'struct snd_rawmidi_status64' to handle 32bit time_t and 64bit time_t in native mode, which replace timespec with s64 type.
In compat mode, we renamed or introduced new structures to handle 32bit/64bit time_t in compatible mode. The 'struct snd_rawmidi_status32' and snd_rawmidi_ioctl_status32() are used to handle 32bit time_t in compat mode. 'struct compat_snd_rawmidi_status64' is used to handle 64bit time_t.
When glibc changes time_t to 64-bit, any recompiled program will issue ioctl commands that the kernel does not understand without this patch.
Signed-off-by: Baolin Wang baolin.wang@linaro.org Signed-off-by: Arnd Bergmann arnd@arndb.de
include/uapi/sound/asound.h | 3 + sound/core/rawmidi.c | 132 ++++++++++++++++++++++++++++-------- sound/core/rawmidi_compat.c | 87 ++++++------------------ 3 files changed, 128 insertions(+), 94 deletions(-)
diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h index 7b74524f9406..cb830813da5d 100644 --- a/include/uapi/sound/asound.h +++ b/include/uapi/sound/asound.h @@ -651,13 +651,16 @@ struct snd_rawmidi_params { unsigned char reserved[16]; /* reserved for future use */ };
+#ifndef __KERNEL__ struct snd_rawmidi_status { int stream;
- unsigned char pad1[sizeof(time_t) - sizeof(int)]; struct timespec tstamp; /* Timestamp */ size_t avail; /* available bytes */ size_t xruns; /* count of overruns since last status (in bytes) */ unsigned char reserved[16]; /* reserved for future use */
};
Can we use union instead of padding? Something like:
struct snd_rawmidi_status { union { int stream; time_t stream_alignment; }; struct timespec tstamp; /* Timestamp */ ....
thanks,
Takashi