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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 03:57:19 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 03:57:19 +0000
commita0b8f38ab54ac451646aa00cd5e91b6c76f22a84 (patch)
treefc451898ccaf445814e26b46664d78702178101d /vendor/memmap2-0.2.3/src/unix.rs
parentAdding debian version 1.71.1+dfsg1-2. (diff)
downloadrustc-a0b8f38ab54ac451646aa00cd5e91b6c76f22a84.tar.xz
rustc-a0b8f38ab54ac451646aa00cd5e91b6c76f22a84.zip
Merging upstream version 1.72.1+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/memmap2-0.2.3/src/unix.rs')
-rw-r--r--vendor/memmap2-0.2.3/src/unix.rs235
1 files changed, 235 insertions, 0 deletions
diff --git a/vendor/memmap2-0.2.3/src/unix.rs b/vendor/memmap2-0.2.3/src/unix.rs
new file mode 100644
index 000000000..2d45e68d6
--- /dev/null
+++ b/vendor/memmap2-0.2.3/src/unix.rs
@@ -0,0 +1,235 @@
+extern crate libc;
+
+use std::fs::File;
+use std::os::unix::io::{AsRawFd, RawFd};
+use std::{io, ptr};
+
+#[cfg(any(
+ all(target_os = "linux", not(target_arch = "mips")),
+ target_os = "freebsd",
+ target_os = "android"
+))]
+const MAP_STACK: libc::c_int = libc::MAP_STACK;
+
+#[cfg(not(any(
+ all(target_os = "linux", not(target_arch = "mips")),
+ target_os = "freebsd",
+ target_os = "android"
+)))]
+const MAP_STACK: libc::c_int = 0;
+
+#[cfg(any(target_os = "linux", target_os = "android"))]
+const MAP_POPULATE: libc::c_int = libc::MAP_POPULATE;
+
+#[cfg(not(any(target_os = "linux", target_os = "android")))]
+const MAP_POPULATE: libc::c_int = 0;
+
+pub struct MmapInner {
+ ptr: *mut libc::c_void,
+ len: usize,
+}
+
+impl MmapInner {
+ /// Creates a new `MmapInner`.
+ ///
+ /// This is a thin wrapper around the `mmap` sytem call.
+ fn new(
+ len: usize,
+ prot: libc::c_int,
+ flags: libc::c_int,
+ file: RawFd,
+ offset: u64,
+ ) -> io::Result<MmapInner> {
+ let alignment = offset % page_size() as u64;
+ let aligned_offset = offset - alignment;
+ let aligned_len = len + alignment as usize;
+ if aligned_len == 0 {
+ // Normally the OS would catch this, but it segfaults under QEMU.
+ return Err(io::Error::new(
+ io::ErrorKind::InvalidInput,
+ "memory map must have a non-zero length",
+ ));
+ }
+
+ unsafe {
+ let ptr = libc::mmap(
+ ptr::null_mut(),
+ aligned_len as libc::size_t,
+ prot,
+ flags,
+ file,
+ aligned_offset as libc::off_t,
+ );
+
+ if ptr == libc::MAP_FAILED {
+ Err(io::Error::last_os_error())
+ } else {
+ Ok(MmapInner {
+ ptr: ptr.offset(alignment as isize),
+ len,
+ })
+ }
+ }
+ }
+
+ pub fn map(len: usize, file: &File, offset: u64, populate: bool) -> io::Result<MmapInner> {
+ let populate = if populate { MAP_POPULATE } else { 0 };
+ MmapInner::new(
+ len,
+ libc::PROT_READ,
+ libc::MAP_SHARED | populate,
+ file.as_raw_fd(),
+ offset,
+ )
+ }
+
+ pub fn map_exec(len: usize, file: &File, offset: u64, populate: bool) -> io::Result<MmapInner> {
+ let populate = if populate { MAP_POPULATE } else { 0 };
+ MmapInner::new(
+ len,
+ libc::PROT_READ | libc::PROT_EXEC,
+ libc::MAP_SHARED | populate,
+ file.as_raw_fd(),
+ offset,
+ )
+ }
+
+ pub fn map_mut(len: usize, file: &File, offset: u64, populate: bool) -> io::Result<MmapInner> {
+ let populate = if populate { MAP_POPULATE } else { 0 };
+ MmapInner::new(
+ len,
+ libc::PROT_READ | libc::PROT_WRITE,
+ libc::MAP_SHARED | populate,
+ file.as_raw_fd(),
+ offset,
+ )
+ }
+
+ pub fn map_copy(len: usize, file: &File, offset: u64, populate: bool) -> io::Result<MmapInner> {
+ let populate = if populate { MAP_POPULATE } else { 0 };
+ MmapInner::new(
+ len,
+ libc::PROT_READ | libc::PROT_WRITE,
+ libc::MAP_PRIVATE | populate,
+ file.as_raw_fd(),
+ offset,
+ )
+ }
+
+ pub fn map_copy_read_only(
+ len: usize,
+ file: &File,
+ offset: u64,
+ populate: bool,
+ ) -> io::Result<MmapInner> {
+ let populate = if populate { MAP_POPULATE } else { 0 };
+ MmapInner::new(
+ len,
+ libc::PROT_READ,
+ libc::MAP_PRIVATE | populate,
+ file.as_raw_fd(),
+ offset,
+ )
+ }
+
+ /// Open an anonymous memory map.
+ pub fn map_anon(len: usize, stack: bool) -> io::Result<MmapInner> {
+ let stack = if stack { MAP_STACK } else { 0 };
+ MmapInner::new(
+ len,
+ libc::PROT_READ | libc::PROT_WRITE,
+ libc::MAP_PRIVATE | libc::MAP_ANON | stack,
+ -1,
+ 0,
+ )
+ }
+
+ pub fn flush(&self, offset: usize, len: usize) -> io::Result<()> {
+ let alignment = (self.ptr as usize + offset) % page_size();
+ let offset = offset as isize - alignment as isize;
+ let len = len + alignment;
+ let result =
+ unsafe { libc::msync(self.ptr.offset(offset), len as libc::size_t, libc::MS_SYNC) };
+ if result == 0 {
+ Ok(())
+ } else {
+ Err(io::Error::last_os_error())
+ }
+ }
+
+ pub fn flush_async(&self, offset: usize, len: usize) -> io::Result<()> {
+ let alignment = (self.ptr as usize + offset) % page_size();
+ let offset = offset as isize - alignment as isize;
+ let len = len + alignment;
+ let result =
+ unsafe { libc::msync(self.ptr.offset(offset), len as libc::size_t, libc::MS_ASYNC) };
+ if result == 0 {
+ Ok(())
+ } else {
+ Err(io::Error::last_os_error())
+ }
+ }
+
+ fn mprotect(&mut self, prot: libc::c_int) -> io::Result<()> {
+ unsafe {
+ let alignment = self.ptr as usize % page_size();
+ let ptr = self.ptr.offset(-(alignment as isize));
+ let len = self.len + alignment;
+ if libc::mprotect(ptr, len, prot) == 0 {
+ Ok(())
+ } else {
+ Err(io::Error::last_os_error())
+ }
+ }
+ }
+
+ pub fn make_read_only(&mut self) -> io::Result<()> {
+ self.mprotect(libc::PROT_READ)
+ }
+
+ pub fn make_exec(&mut self) -> io::Result<()> {
+ self.mprotect(libc::PROT_READ | libc::PROT_EXEC)
+ }
+
+ pub fn make_mut(&mut self) -> io::Result<()> {
+ self.mprotect(libc::PROT_READ | libc::PROT_WRITE)
+ }
+
+ #[inline]
+ pub fn ptr(&self) -> *const u8 {
+ self.ptr as *const u8
+ }
+
+ #[inline]
+ pub fn mut_ptr(&mut self) -> *mut u8 {
+ self.ptr as *mut u8
+ }
+
+ #[inline]
+ pub fn len(&self) -> usize {
+ self.len
+ }
+}
+
+impl Drop for MmapInner {
+ fn drop(&mut self) {
+ let alignment = self.ptr as usize % page_size();
+ unsafe {
+ assert!(
+ libc::munmap(
+ self.ptr.offset(-(alignment as isize)),
+ (self.len + alignment) as libc::size_t
+ ) == 0,
+ "unable to unmap mmap: {}",
+ io::Error::last_os_error()
+ );
+ }
+ }
+}
+
+unsafe impl Sync for MmapInner {}
+unsafe impl Send for MmapInner {}
+
+fn page_size() -> usize {
+ unsafe { libc::sysconf(libc::_SC_PAGESIZE) as usize }
+}