3733c831f293b3bbfd0e51faec8ee71112c62c3e
the snd_pcm_mmap_control struct used with SNDRV_PCM_IOCTL_SYNC_PTR was mistakenly defined in the kernel uapi with "before u32" padding both before and after the first u32 member. our conversion between the modern struct and the legacy time32 struct was written without awareness of that mistake, and assumed the time64 version of the struct was the intended form with padding to match the layout on 64-bit archs. as a result, the struct was not converted correctly when running on old kernels, with audio glitches as the likely result. this was discovered thanks to a related bug in the kernel, whereby 32-bit userspace running on a 64-bit kernel also suffered from the types mismatching. the mistaken layout is now the ABI and can't be changed -- or at least making a new ioctl to change it would just result in a worse situation. our conversion here is changed to treat the snd_pcm_mmap_control substruct as two separate substructs at locations dependent on endianness (since the displacement depends on endianness), using the existing conversion framework.
musl libc
musl, pronounced like the word "mussel", is an MIT-licensed
implementation of the standard C library targetting the Linux syscall
API, suitable for use in a wide range of deployment environments. musl
offers efficient static and dynamic linking support, lightweight code
and low runtime overhead, strong fail-safe guarantees under correct
usage, and correctness in the sense of standards conformance and
safety. musl is built on the principle that these goals are best
achieved through simple code that is easy to understand and maintain.
The 1.1 release series for musl features coverage for all interfaces
defined in ISO C99 and POSIX 2008 base, along with a number of
non-standardized interfaces for compatibility with Linux, BSD, and
glibc functionality.
For basic installation instructions, see the included INSTALL file.
Information on full musl-targeted compiler toolchains, system
bootstrapping, and Linux distributions built on musl can be found on
the project website:
http://www.musl-libc.org/