fix: support ALSA timestamps on 32-bit musl time64

vendor/alsa/src/direct/ffi.rs

@@ -0,0 +1,212 @@
+//! Some definitions from the kernel headers
+
+#![allow(non_camel_case_types)]
+
+use cfg_if::cfg_if;
+
+// const SNDRV_PCM_MMAP_OFFSET_DATA: c_uint = 0x00000000;
+pub const SNDRV_PCM_MMAP_OFFSET_STATUS: libc::c_uint = 0x80000000;
+pub const SNDRV_PCM_MMAP_OFFSET_CONTROL: libc::c_uint = 0x81000000;
+
+pub const SNDRV_PCM_SYNC_PTR_HWSYNC: libc::c_uint = 1;
+pub const SNDRV_PCM_SYNC_PTR_APPL: libc::c_uint = 2;
+pub const SNDRV_PCM_SYNC_PTR_AVAIL_MIN: libc::c_uint = 4;
+
+// #[repr(C)]
+#[allow(non_camel_case_types)]
+pub type snd_pcm_state_t = libc::c_int;
+
+// #[repr(C)]
+#[allow(non_camel_case_types)]
+pub type snd_pcm_uframes_t = libc::c_ulong;
+
+// I think?! Not sure how this will work with X32 ABI?!
+#[allow(non_camel_case_types)]
+pub type __kernel_off_t = libc::c_long;
+
+#[repr(C)]
+#[derive(Copy, Clone, Debug)]
+pub struct snd_pcm_mmap_status {
+    pub state: snd_pcm_state_t,    /* RO: state - SNDRV_PCM_STATE_XXXX */
+    pub pad1: libc::c_int,         /* Needed for 64 bit alignment */
+    pub hw_ptr: snd_pcm_uframes_t, /* RO: hw ptr (0...boundary-1) */
+    pub tstamp: libc::timespec,    /* Timestamp */
+    pub suspended_state: snd_pcm_state_t, /* RO: suspended stream state */
+    pub audio_tstamp: libc::timespec, /* from sample counter or wall clock */
+}
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct snd_pcm_mmap_control {
+    pub appl_ptr: snd_pcm_uframes_t,  /* RW: appl ptr (0...boundary-1) */
+    pub avail_min: snd_pcm_uframes_t, /* RW: min available frames for wakeup */
+}
+
+#[repr(C)]
+#[derive(Debug)]
+pub struct snd_pcm_channel_info {
+    pub channel: libc::c_uint,
+    pub offset: __kernel_off_t, /* mmap offset */
+    pub first: libc::c_uint,    /* offset to first sample in bits */
+    pub step: libc::c_uint,     /* samples distance in bits */
+}
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub union snd_pcm_mmap_status_r {
+    pub status: snd_pcm_mmap_status,
+    pub reserved: [libc::c_uchar; 64],
+}
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub union snd_pcm_mmap_control_r {
+    pub control: snd_pcm_mmap_control,
+    pub reserved: [libc::c_uchar; 64],
+}
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct snd_pcm_sync_ptr {
+    pub flags: libc::c_uint,
+    pub s: snd_pcm_mmap_status_r,
+    pub c: snd_pcm_mmap_control_r,
+}
+
+cfg_if! {
+    if #[cfg(any(target_os = "linux", target_os = "android"))] {
+        // See <https://github.com/nix-rust/nix/blob/197f55b3ccbce3273bf6ce119d1a8541b5df5d66/src/sys/ioctl/linux.rs>
+
+        cfg_if! {
+            if #[cfg(any(target_os = "android", target_env = "musl"))] {
+                pub(super) type ioctl_num_type = libc::c_int;
+            } else {
+                pub(super) type ioctl_num_type = libc::c_ulong;
+            }
+        }
+
+        // The READ dir is consistent across arches
+        pub(super) const READ: ioctl_num_type = 2;
+
+        // But WRITE is not, as well as having a different number of bits for the SIZEBITS
+        cfg_if!{
+            if #[cfg(any(
+                target_arch = "mips",
+                target_arch = "mips32r6",
+                target_arch = "mips64",
+                target_arch = "mips64r6",
+                target_arch = "powerpc",
+                target_arch = "powerpc64",
+                target_arch = "sparc64"
+            ))] {
+                pub(super) const WRITE: ioctl_num_type = 4;
+                const SIZEBITS: ioctl_num_type = 13;
+            } else {
+                pub(super) const WRITE: ioctl_num_type = 1;
+                const SIZEBITS: ioctl_num_type = 14;
+            }
+        }
+
+        const NRSHIFT: ioctl_num_type = 0;
+        const NRBITS: ioctl_num_type = 8;
+        const TYPEBITS: ioctl_num_type = 8;
+        const TYPESHIFT: ioctl_num_type = NRSHIFT + NRBITS;
+        const SIZESHIFT: ioctl_num_type = TYPESHIFT + TYPEBITS;
+        const DIRSHIFT: ioctl_num_type = SIZESHIFT + SIZEBITS;
+
+        /// Replication of the [`nix::ioc!`](https://github.com/nix-rust/nix/blob/197f55b3ccbce3273bf6ce119d1a8541b5df5d66/src/sys/ioctl/linux.rs#L78-L96)
+        pub(super) const fn make_request(
+            dir: ioctl_num_type,
+            typ: u8,
+            nr: u8,
+            size: usize,
+        ) -> ioctl_num_type {
+            dir << DIRSHIFT
+                | (typ as ioctl_num_type) << TYPESHIFT
+                | (nr as ioctl_num_type) << NRSHIFT
+                | (size as ioctl_num_type) << SIZESHIFT
+        }
+    } else if #[cfg(any(
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "netbsd",
+        target_os = "openbsd",
+        target_os = "solaris",
+        target_os = "illumos"
+    ))] {
+        // See <https://github.com/nix-rust/nix/blob/197f55b3ccbce3273bf6ce119d1a8541b5df5d66/src/sys/ioctl/bsd.rs>
+
+        cfg_if! {
+            if #[cfg(not(any(target_os = "illumos", target_os = "solaris")))] {
+                pub(super) type ioctl_num_type = libc::c_ulong;
+            } else {
+                pub(super) type ioctl_num_type = libc::c_int;
+            }
+        }
+
+        #[allow(overflowing_literals)]
+        pub(super) const READ: ioctl_num_type = 0x4000_0000;
+        #[allow(overflowing_literals)]
+        pub(super) const WRITE: ioctl_num_type = 0x8000_0000;
+
+        const IOCPARM_MASK: ioctl_num_type = 0x1fff;
+
+        /// Replication of [`nix::ioc!`](https://github.com/nix-rust/nix/blob/197f55b3ccbce3273bf6ce119d1a8541b5df5d66/src/sys/ioctl/bsd.rs#L31-L42)
+        pub(super) const fn make_request(
+            dir: ioctl_num_type,
+            typ: u8,
+            nr: u8,
+            size: usize,
+        ) -> ioctl_num_type {
+            dir | ((size as ioctl_num_type) & IOCPARM_MASK) << 16
+                | (typ as ioctl_num_type) << 8
+                | nr as ioctl_num_type
+        }
+    } else {
+        compile_error!("unknown target platform");
+    }
+}
+
+pub(crate) unsafe fn sndrv_pcm_ioctl_channel_info(
+    fd: libc::c_int,
+    data: *mut snd_pcm_channel_info,
+) -> Result<(), crate::Error> {
+    const REQUEST: ioctl_num_type = make_request(
+        READ,
+        b'A',
+        0x32,
+        core::mem::size_of::<snd_pcm_channel_info>(),
+    );
+
+    unsafe {
+        if libc::ioctl(fd, REQUEST, data) == -1 {
+            Err(crate::Error::last("SNDRV_PCM_IOCTL_CHANNEL_INFO"))
+        } else {
+            Ok(())
+        }
+    }
+}
+
+pub(crate) unsafe fn sndrv_pcm_ioctl_sync_ptr(
+    fd: libc::c_int,
+    data: *mut snd_pcm_sync_ptr,
+) -> Result<(), crate::Error> {
+    const REQUEST: ioctl_num_type = make_request(
+        READ | WRITE,
+        b'A',
+        0x23,
+        core::mem::size_of::<snd_pcm_sync_ptr>(),
+    );
+
+    unsafe {
+        if libc::ioctl(fd, REQUEST, data) == -1 {
+            Err(crate::Error::last("SNDRV_PCM_IOCTL_SYNC_PTR"))
+        } else {
+            Ok(())
+        }
+    }
+}
+
+pub fn pagesize() -> usize {
+    unsafe { libc::sysconf(libc::_SC_PAGESIZE) as usize }
+}