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1471 lines (1273 loc) · 50.3 KB
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// spell-checker:disable
//! mmap module
pub(crate) use mmap::make_module;
#[pymodule]
mod mmap {
use crate::common::{
borrow::{BorrowedValue, BorrowedValueMut},
lock::{MapImmutable, PyMutex, PyMutexGuard},
};
use crate::vm::{
AsObject, FromArgs, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
TryFromBorrowedObject, VirtualMachine, atomic_func,
builtins::{PyBytes, PyBytesRef, PyInt, PyIntRef, PyType, PyTypeRef},
byte::{bytes_from_object, value_from_object},
convert::ToPyException,
function::{ArgBytesLike, FuncArgs, OptionalArg},
protocol::{
BufferDescriptor, BufferMethods, PyBuffer, PyMappingMethods, PySequenceMethods,
},
sliceable::{SaturatedSlice, SequenceIndex, SequenceIndexOp},
types::{AsBuffer, AsMapping, AsSequence, Constructor, Representable},
};
use crossbeam_utils::atomic::AtomicCell;
use memmap2::{Mmap, MmapMut, MmapOptions};
use num_traits::Signed;
use std::io::{self, Write};
use std::ops::{Deref, DerefMut};
#[cfg(unix)]
use nix::{sys::stat::fstat, unistd};
#[cfg(unix)]
use rustpython_common::crt_fd;
#[cfg(windows)]
use rustpython_common::suppress_iph;
#[cfg(windows)]
use std::os::windows::io::{AsRawHandle, FromRawHandle, OwnedHandle, RawHandle};
#[cfg(windows)]
use windows_sys::Win32::{
Foundation::{
CloseHandle, DUPLICATE_SAME_ACCESS, DuplicateHandle, HANDLE, INVALID_HANDLE_VALUE,
},
Storage::FileSystem::{FILE_BEGIN, GetFileSize, SetEndOfFile, SetFilePointerEx},
System::Threading::GetCurrentProcess,
};
#[cfg(unix)]
fn validate_advice(vm: &VirtualMachine, advice: i32) -> PyResult<i32> {
match advice {
libc::MADV_NORMAL
| libc::MADV_RANDOM
| libc::MADV_SEQUENTIAL
| libc::MADV_WILLNEED
| libc::MADV_DONTNEED => Ok(advice),
#[cfg(any(
target_os = "linux",
target_os = "macos",
target_os = "ios",
target_os = "freebsd"
))]
libc::MADV_FREE => Ok(advice),
#[cfg(target_os = "linux")]
libc::MADV_DONTFORK
| libc::MADV_DOFORK
| libc::MADV_MERGEABLE
| libc::MADV_UNMERGEABLE
| libc::MADV_HUGEPAGE
| libc::MADV_NOHUGEPAGE
| libc::MADV_REMOVE
| libc::MADV_DONTDUMP
| libc::MADV_DODUMP
| libc::MADV_HWPOISON => Ok(advice),
#[cfg(target_os = "freebsd")]
libc::MADV_NOSYNC
| libc::MADV_AUTOSYNC
| libc::MADV_NOCORE
| libc::MADV_CORE
| libc::MADV_PROTECT => Ok(advice),
_ => Err(vm.new_value_error("Not a valid Advice value")),
}
}
#[repr(C)]
#[derive(PartialEq, Eq, Debug)]
enum AccessMode {
Default = 0,
Read = 1,
Write = 2,
Copy = 3,
}
impl<'a> TryFromBorrowedObject<'a> for AccessMode {
fn try_from_borrowed_object(vm: &VirtualMachine, obj: &'a PyObject) -> PyResult<Self> {
let i = u32::try_from_borrowed_object(vm, obj)?;
Ok(match i {
0 => Self::Default,
1 => Self::Read,
2 => Self::Write,
3 => Self::Copy,
_ => return Err(vm.new_value_error("Not a valid AccessMode value")),
})
}
}
#[cfg(unix)]
#[pyattr]
use libc::{
MADV_DONTNEED, MADV_NORMAL, MADV_RANDOM, MADV_SEQUENTIAL, MADV_WILLNEED, MAP_ANON,
MAP_ANONYMOUS, MAP_PRIVATE, MAP_SHARED, PROT_EXEC, PROT_READ, PROT_WRITE,
};
#[cfg(target_os = "macos")]
#[pyattr]
use libc::{MADV_FREE_REUSABLE, MADV_FREE_REUSE};
#[cfg(any(
target_os = "android",
target_os = "dragonfly",
target_os = "fuchsia",
target_os = "freebsd",
target_os = "linux",
target_os = "netbsd",
target_os = "openbsd",
target_vendor = "apple"
))]
#[pyattr]
use libc::MADV_FREE;
#[cfg(target_os = "linux")]
#[pyattr]
use libc::{
MADV_DODUMP, MADV_DOFORK, MADV_DONTDUMP, MADV_DONTFORK, MADV_HUGEPAGE, MADV_HWPOISON,
MADV_MERGEABLE, MADV_NOHUGEPAGE, MADV_REMOVE, MADV_UNMERGEABLE,
};
#[cfg(any(
target_os = "android",
all(
target_os = "linux",
any(
target_arch = "aarch64",
target_arch = "arm",
target_arch = "powerpc",
target_arch = "powerpc64",
target_arch = "s390x",
target_arch = "x86",
target_arch = "x86_64",
target_arch = "sparc64"
)
)
))]
#[pyattr]
use libc::MADV_SOFT_OFFLINE;
#[cfg(all(target_os = "linux", target_arch = "x86_64", target_env = "gnu"))]
#[pyattr]
use libc::{MAP_DENYWRITE, MAP_EXECUTABLE, MAP_POPULATE};
// MAP_STACK is available on Linux, OpenBSD, and NetBSD
#[cfg(any(target_os = "linux", target_os = "openbsd", target_os = "netbsd"))]
#[pyattr]
use libc::MAP_STACK;
// FreeBSD-specific MADV constants
#[cfg(target_os = "freebsd")]
#[pyattr]
use libc::{MADV_AUTOSYNC, MADV_CORE, MADV_NOCORE, MADV_NOSYNC, MADV_PROTECT};
#[pyattr]
const ACCESS_DEFAULT: u32 = AccessMode::Default as u32;
#[pyattr]
const ACCESS_READ: u32 = AccessMode::Read as u32;
#[pyattr]
const ACCESS_WRITE: u32 = AccessMode::Write as u32;
#[pyattr]
const ACCESS_COPY: u32 = AccessMode::Copy as u32;
#[cfg(not(target_arch = "wasm32"))]
#[pyattr(name = "PAGESIZE", once)]
fn page_size(_vm: &VirtualMachine) -> usize {
page_size::get()
}
#[cfg(not(target_arch = "wasm32"))]
#[pyattr(name = "ALLOCATIONGRANULARITY", once)]
fn granularity(_vm: &VirtualMachine) -> usize {
page_size::get_granularity()
}
#[pyattr(name = "error", once)]
fn error_type(vm: &VirtualMachine) -> PyTypeRef {
vm.ctx.exceptions.os_error.to_owned()
}
#[derive(Debug)]
enum MmapObj {
Write(MmapMut),
Read(Mmap),
}
impl MmapObj {
fn as_slice(&self) -> &[u8] {
match self {
MmapObj::Read(mmap) => &mmap[..],
MmapObj::Write(mmap) => &mmap[..],
}
}
}
#[pyattr]
#[pyclass(name = "mmap")]
#[derive(Debug, PyPayload)]
struct PyMmap {
closed: AtomicCell<bool>,
mmap: PyMutex<Option<MmapObj>>,
#[cfg(unix)]
fd: AtomicCell<i32>,
#[cfg(windows)]
handle: AtomicCell<isize>, // HANDLE is isize on Windows
offset: i64,
size: AtomicCell<usize>,
pos: AtomicCell<usize>, // relative to offset
exports: AtomicCell<usize>,
access: AccessMode,
}
impl PyMmap {
/// Close the underlying file handle/descriptor if open
fn close_handle(&self) {
#[cfg(unix)]
{
let fd = self.fd.swap(-1);
if fd >= 0 {
unsafe { libc::close(fd) };
}
}
#[cfg(windows)]
{
let handle = self.handle.swap(INVALID_HANDLE_VALUE as isize);
if handle != INVALID_HANDLE_VALUE as isize {
unsafe { CloseHandle(handle as HANDLE) };
}
}
}
}
impl Drop for PyMmap {
fn drop(&mut self) {
self.close_handle();
}
}
#[cfg(unix)]
#[derive(FromArgs)]
struct MmapNewArgs {
#[pyarg(any)]
fileno: i32,
#[pyarg(any)]
length: isize,
#[pyarg(any, default = libc::MAP_SHARED)]
flags: libc::c_int,
#[pyarg(any, default = libc::PROT_WRITE | libc::PROT_READ)]
prot: libc::c_int,
#[pyarg(any, default = AccessMode::Default)]
access: AccessMode,
#[pyarg(any, default = 0)]
offset: i64,
}
#[cfg(windows)]
#[derive(FromArgs)]
struct MmapNewArgs {
#[pyarg(any)]
fileno: i32,
#[pyarg(any)]
length: isize,
#[pyarg(any, default)]
#[allow(dead_code)]
tagname: Option<PyObjectRef>,
#[pyarg(any, default = AccessMode::Default)]
access: AccessMode,
#[pyarg(any, default = 0)]
offset: i64,
}
impl MmapNewArgs {
/// Validate mmap constructor arguments
fn validate_new_args(&self, vm: &VirtualMachine) -> PyResult<usize> {
if self.length < 0 {
return Err(vm.new_overflow_error("memory mapped length must be positive"));
}
if self.offset < 0 {
return Err(vm.new_overflow_error("memory mapped offset must be positive"));
}
Ok(self.length as usize)
}
}
#[derive(FromArgs)]
pub struct FlushOptions {
#[pyarg(positional, default)]
offset: Option<isize>,
#[pyarg(positional, default)]
size: Option<isize>,
}
impl FlushOptions {
fn values(self, len: usize) -> Option<(usize, usize)> {
let offset = match self.offset {
Some(o) if o < 0 => return None,
Some(o) => o as usize,
None => 0,
};
let size = match self.size {
Some(s) if s < 0 => return None,
Some(s) => s as usize,
None => len,
};
if len.checked_sub(offset)? < size {
return None;
}
Some((offset, size))
}
}
#[derive(FromArgs, Clone)]
pub struct FindOptions {
#[pyarg(positional)]
sub: Vec<u8>,
#[pyarg(positional, default)]
start: Option<isize>,
#[pyarg(positional, default)]
end: Option<isize>,
}
#[cfg(all(unix, not(target_os = "redox")))]
#[derive(FromArgs)]
pub struct AdviseOptions {
#[pyarg(positional)]
option: libc::c_int,
#[pyarg(positional, default)]
start: Option<PyIntRef>,
#[pyarg(positional, default)]
length: Option<PyIntRef>,
}
#[cfg(all(unix, not(target_os = "redox")))]
impl AdviseOptions {
fn values(self, len: usize, vm: &VirtualMachine) -> PyResult<(libc::c_int, usize, usize)> {
let start = self
.start
.map(|s| {
s.try_to_primitive::<usize>(vm)
.ok()
.filter(|s| *s < len)
.ok_or_else(|| vm.new_value_error("madvise start out of bounds"))
})
.transpose()?
.unwrap_or(0);
let length = self
.length
.map(|s| {
s.try_to_primitive::<usize>(vm)
.map_err(|_| vm.new_value_error("madvise length invalid"))
})
.transpose()?
.unwrap_or(len);
if isize::MAX as usize - start < length {
return Err(vm.new_overflow_error("madvise length too large"));
}
let length = if start + length > len {
len - start
} else {
length
};
Ok((self.option, start, length))
}
}
impl Constructor for PyMmap {
type Args = MmapNewArgs;
#[cfg(unix)]
fn py_new(_cls: &Py<PyType>, args: Self::Args, vm: &VirtualMachine) -> PyResult<Self> {
use libc::{MAP_PRIVATE, MAP_SHARED, PROT_READ, PROT_WRITE};
let mut map_size = args.validate_new_args(vm)?;
let MmapNewArgs {
fileno: fd,
flags,
prot,
access,
offset,
..
} = args;
if (access != AccessMode::Default)
&& ((flags != MAP_SHARED) || (prot != (PROT_WRITE | PROT_READ)))
{
return Err(vm.new_value_error("mmap can't specify both access and flags, prot."));
}
// TODO: memmap2 doesn't support mapping with prot and flags right now
let (_flags, _prot, access) = match access {
AccessMode::Read => (MAP_SHARED, PROT_READ, access),
AccessMode::Write => (MAP_SHARED, PROT_READ | PROT_WRITE, access),
AccessMode::Copy => (MAP_PRIVATE, PROT_READ | PROT_WRITE, access),
AccessMode::Default => {
let access = if (prot & PROT_READ) != 0 && (prot & PROT_WRITE) != 0 {
access
} else if (prot & PROT_WRITE) != 0 {
AccessMode::Write
} else {
AccessMode::Read
};
(flags, prot, access)
}
};
let fd = unsafe { crt_fd::Borrowed::try_borrow_raw(fd) };
// macOS: Issue #11277: fsync(2) is not enough on OS X - a special, OS X specific
// fcntl(2) is necessary to force DISKSYNC and get around mmap(2) bug
#[cfg(target_os = "macos")]
if let Ok(fd) = fd {
use std::os::fd::AsRawFd;
unsafe { libc::fcntl(fd.as_raw_fd(), libc::F_FULLFSYNC) };
}
if let Ok(fd) = fd {
let metadata = fstat(fd)
.map_err(|err| io::Error::from_raw_os_error(err as i32).to_pyexception(vm))?;
let file_len = metadata.st_size as i64;
if map_size == 0 {
if file_len == 0 {
return Err(vm.new_value_error("cannot mmap an empty file"));
}
if offset > file_len {
return Err(vm.new_value_error("mmap offset is greater than file size"));
}
map_size = (file_len - offset)
.try_into()
.map_err(|_| vm.new_value_error("mmap length is too large"))?;
} else if offset > file_len || file_len - offset < map_size as i64 {
return Err(vm.new_value_error("mmap length is greater than file size"));
}
}
let mut mmap_opt = MmapOptions::new();
let mmap_opt = mmap_opt.offset(offset as u64).len(map_size);
let (fd, mmap) = || -> std::io::Result<_> {
if let Ok(fd) = fd {
let new_fd: crt_fd::Owned = unistd::dup(fd)?.into();
let mmap = match access {
AccessMode::Default | AccessMode::Write => {
MmapObj::Write(unsafe { mmap_opt.map_mut(&new_fd) }?)
}
AccessMode::Read => MmapObj::Read(unsafe { mmap_opt.map(&new_fd) }?),
AccessMode::Copy => MmapObj::Write(unsafe { mmap_opt.map_copy(&new_fd) }?),
};
Ok((Some(new_fd), mmap))
} else {
let mmap = MmapObj::Write(mmap_opt.map_anon()?);
Ok((None, mmap))
}
}()
.map_err(|e| e.to_pyexception(vm))?;
Ok(Self {
closed: AtomicCell::new(false),
mmap: PyMutex::new(Some(mmap)),
fd: AtomicCell::new(fd.map_or(-1, |fd| fd.into_raw())),
offset,
size: AtomicCell::new(map_size),
pos: AtomicCell::new(0),
exports: AtomicCell::new(0),
access,
})
}
#[cfg(windows)]
fn py_new(_cls: &Py<PyType>, args: Self::Args, vm: &VirtualMachine) -> PyResult<Self> {
let mut map_size = args.validate_new_args(vm)?;
let MmapNewArgs {
fileno,
access,
offset,
..
} = args;
// Get file handle from fileno
// fileno -1 or 0 means anonymous mapping
let fh: Option<HANDLE> = if fileno != -1 && fileno != 0 {
// Convert CRT file descriptor to Windows HANDLE
// Use suppress_iph! to avoid crashes when the fd is invalid.
// This is critical because socket fds wrapped via _open_osfhandle
// may cause crashes in _get_osfhandle on Windows.
// See Python bug https://bugs.python.org/issue30114
let handle = unsafe { suppress_iph!(libc::get_osfhandle(fileno)) };
// Check for invalid handle value (-1 on Windows)
if handle == -1 || handle == INVALID_HANDLE_VALUE as isize {
return Err(vm.new_os_error(format!("Invalid file descriptor: {}", fileno)));
}
Some(handle as HANDLE)
} else {
None
};
// Get file size if we have a file handle and map_size is 0
let mut duplicated_handle: HANDLE = INVALID_HANDLE_VALUE;
if let Some(fh) = fh {
// Duplicate handle so Python code can close the original
let mut new_handle: HANDLE = INVALID_HANDLE_VALUE;
let result = unsafe {
DuplicateHandle(
GetCurrentProcess(),
fh,
GetCurrentProcess(),
&mut new_handle,
0,
0, // not inheritable
DUPLICATE_SAME_ACCESS,
)
};
if result == 0 {
return Err(io::Error::last_os_error().to_pyexception(vm));
}
duplicated_handle = new_handle;
// Get file size
let mut high: u32 = 0;
let low = unsafe { GetFileSize(fh, &mut high) };
if low == u32::MAX {
let err = io::Error::last_os_error();
if err.raw_os_error() != Some(0) {
unsafe { CloseHandle(duplicated_handle) };
return Err(err.to_pyexception(vm));
}
}
let file_len = ((high as i64) << 32) | (low as i64);
if map_size == 0 {
if file_len == 0 {
unsafe { CloseHandle(duplicated_handle) };
return Err(vm.new_value_error("cannot mmap an empty file"));
}
if offset >= file_len {
unsafe { CloseHandle(duplicated_handle) };
return Err(vm.new_value_error("mmap offset is greater than file size"));
}
if file_len - offset > isize::MAX as i64 {
unsafe { CloseHandle(duplicated_handle) };
return Err(vm.new_value_error("mmap length is too large"));
}
map_size = (file_len - offset) as usize;
} else {
// If map_size > file_len, extend the file (Windows behavior)
let required_size = offset.checked_add(map_size as i64).ok_or_else(|| {
unsafe { CloseHandle(duplicated_handle) };
vm.new_overflow_error("mmap size would cause file size overflow")
})?;
if required_size > file_len {
// Extend file using SetFilePointerEx + SetEndOfFile
let result = unsafe {
SetFilePointerEx(
duplicated_handle,
required_size,
std::ptr::null_mut(),
FILE_BEGIN,
)
};
if result == 0 {
let err = io::Error::last_os_error();
unsafe { CloseHandle(duplicated_handle) };
return Err(err.to_pyexception(vm));
}
let result = unsafe { SetEndOfFile(duplicated_handle) };
if result == 0 {
let err = io::Error::last_os_error();
unsafe { CloseHandle(duplicated_handle) };
return Err(err.to_pyexception(vm));
}
}
}
}
let mut mmap_opt = MmapOptions::new();
let mmap_opt = mmap_opt.offset(offset as u64).len(map_size);
let (handle, mmap) = if duplicated_handle != INVALID_HANDLE_VALUE {
// Safety: We just duplicated this handle and it's valid
let owned_handle =
unsafe { OwnedHandle::from_raw_handle(duplicated_handle as RawHandle) };
let mmap_result = match access {
AccessMode::Default | AccessMode::Write => {
unsafe { mmap_opt.map_mut(&owned_handle) }.map(MmapObj::Write)
}
AccessMode::Read => unsafe { mmap_opt.map(&owned_handle) }.map(MmapObj::Read),
AccessMode::Copy => {
unsafe { mmap_opt.map_copy(&owned_handle) }.map(MmapObj::Write)
}
};
let mmap = mmap_result.map_err(|e| e.to_pyexception(vm))?;
// Keep the handle alive
let raw = owned_handle.as_raw_handle() as isize;
std::mem::forget(owned_handle);
(raw, mmap)
} else {
// Anonymous mapping
let mmap = mmap_opt.map_anon().map_err(|e| e.to_pyexception(vm))?;
(INVALID_HANDLE_VALUE as isize, MmapObj::Write(mmap))
};
Ok(Self {
closed: AtomicCell::new(false),
mmap: PyMutex::new(Some(mmap)),
handle: AtomicCell::new(handle),
offset,
size: AtomicCell::new(map_size),
pos: AtomicCell::new(0),
exports: AtomicCell::new(0),
access,
})
}
}
static BUFFER_METHODS: BufferMethods = BufferMethods {
obj_bytes: |buffer| buffer.obj_as::<PyMmap>().as_bytes(),
obj_bytes_mut: |buffer| buffer.obj_as::<PyMmap>().as_bytes_mut(),
release: |buffer| {
buffer.obj_as::<PyMmap>().exports.fetch_sub(1);
},
retain: |buffer| {
buffer.obj_as::<PyMmap>().exports.fetch_add(1);
},
};
impl AsBuffer for PyMmap {
fn as_buffer(zelf: &Py<Self>, _vm: &VirtualMachine) -> PyResult<PyBuffer> {
let readonly = matches!(zelf.access, AccessMode::Read);
let buf = PyBuffer::new(
zelf.to_owned().into(),
BufferDescriptor::simple(zelf.__len__(), readonly),
&BUFFER_METHODS,
);
Ok(buf)
}
}
impl AsMapping for PyMmap {
fn as_mapping() -> &'static PyMappingMethods {
static AS_MAPPING: PyMappingMethods = PyMappingMethods {
length: atomic_func!(
|mapping, _vm| Ok(PyMmap::mapping_downcast(mapping).__len__())
),
subscript: atomic_func!(|mapping, needle, vm| {
PyMmap::mapping_downcast(mapping).getitem_inner(needle, vm)
}),
ass_subscript: atomic_func!(|mapping, needle, value, vm| {
let zelf = PyMmap::mapping_downcast(mapping);
if let Some(value) = value {
PyMmap::setitem_inner(zelf, needle, value, vm)
} else {
Err(vm
.new_type_error("mmap object doesn't support item deletion".to_owned()))
}
}),
};
&AS_MAPPING
}
}
impl AsSequence for PyMmap {
fn as_sequence() -> &'static PySequenceMethods {
use std::sync::LazyLock;
static AS_SEQUENCE: LazyLock<PySequenceMethods> = LazyLock::new(|| PySequenceMethods {
length: atomic_func!(|seq, _vm| Ok(PyMmap::sequence_downcast(seq).__len__())),
item: atomic_func!(|seq, i, vm| {
let zelf = PyMmap::sequence_downcast(seq);
zelf.getitem_by_index(i, vm)
}),
ass_item: atomic_func!(|seq, i, value, vm| {
let zelf = PyMmap::sequence_downcast(seq);
if let Some(value) = value {
PyMmap::setitem_by_index(zelf, i, value, vm)
} else {
Err(vm
.new_type_error("mmap object doesn't support item deletion".to_owned()))
}
}),
..PySequenceMethods::NOT_IMPLEMENTED
});
&AS_SEQUENCE
}
}
#[pyclass(
with(Constructor, AsMapping, AsSequence, AsBuffer, Representable),
flags(BASETYPE)
)]
impl PyMmap {
fn as_bytes_mut(&self) -> BorrowedValueMut<'_, [u8]> {
PyMutexGuard::map(self.mmap.lock(), |m| {
match m.as_mut().expect("mmap closed or invalid") {
MmapObj::Read(_) => panic!("mmap can't modify a readonly memory map."),
MmapObj::Write(mmap) => &mut mmap[..],
}
})
.into()
}
fn as_bytes(&self) -> BorrowedValue<'_, [u8]> {
PyMutexGuard::map_immutable(self.mmap.lock(), |m| {
m.as_ref().expect("mmap closed or invalid").as_slice()
})
.into()
}
#[pymethod]
fn __len__(&self) -> usize {
self.size.load()
}
#[inline]
fn pos(&self) -> usize {
self.pos.load()
}
#[inline]
fn advance_pos(&self, step: usize) {
self.pos.store(self.pos() + step);
}
#[inline]
fn try_writable<R>(
&self,
vm: &VirtualMachine,
f: impl FnOnce(&mut MmapMut) -> R,
) -> PyResult<R> {
if matches!(self.access, AccessMode::Read) {
return Err(vm.new_type_error("mmap can't modify a readonly memory map."));
}
match self.check_valid(vm)?.deref_mut().as_mut().unwrap() {
MmapObj::Write(mmap) => Ok(f(mmap)),
_ => unreachable!("already check"),
}
}
fn check_valid(&self, vm: &VirtualMachine) -> PyResult<PyMutexGuard<'_, Option<MmapObj>>> {
let m = self.mmap.lock();
if m.is_none() {
return Err(vm.new_value_error("mmap closed or invalid"));
}
Ok(m)
}
/// TODO: impl resize
#[allow(dead_code)]
fn check_resizeable(&self, vm: &VirtualMachine) -> PyResult<()> {
if self.exports.load() > 0 {
return Err(vm.new_buffer_error("mmap can't resize with extant buffers exported."));
}
if self.access == AccessMode::Write || self.access == AccessMode::Default {
return Ok(());
}
Err(vm.new_type_error("mmap can't resize a readonly or copy-on-write memory map."))
}
#[pygetset]
fn closed(&self) -> bool {
self.closed.load()
}
#[pymethod]
fn close(&self, vm: &VirtualMachine) -> PyResult<()> {
if self.closed() {
return Ok(());
}
if self.exports.load() > 0 {
return Err(vm.new_buffer_error("cannot close exported pointers exist."));
}
let mut mmap = self.mmap.lock();
self.closed.store(true);
*mmap = None;
self.close_handle();
Ok(())
}
fn get_find_range(&self, options: FindOptions) -> (usize, usize) {
let size = self.__len__();
let start = options
.start
.map(|start| start.saturated_at(size))
.unwrap_or_else(|| self.pos());
let end = options
.end
.map(|end| end.saturated_at(size))
.unwrap_or(size);
(start, end)
}
#[pymethod]
fn find(&self, options: FindOptions, vm: &VirtualMachine) -> PyResult<PyInt> {
let (start, end) = self.get_find_range(options.clone());
let sub = &options.sub;
// returns start position for empty string
if sub.is_empty() {
return Ok(PyInt::from(start as isize));
}
let mmap = self.check_valid(vm)?;
let buf = &mmap.as_ref().unwrap().as_slice()[start..end];
let pos = buf.windows(sub.len()).position(|window| window == sub);
Ok(pos.map_or(PyInt::from(-1isize), |i| PyInt::from(start + i)))
}
#[pymethod]
fn rfind(&self, options: FindOptions, vm: &VirtualMachine) -> PyResult<PyInt> {
let (start, end) = self.get_find_range(options.clone());
let sub = &options.sub;
// returns start position for empty string
if sub.is_empty() {
return Ok(PyInt::from(start as isize));
}
let mmap = self.check_valid(vm)?;
let buf = &mmap.as_ref().unwrap().as_slice()[start..end];
let pos = buf.windows(sub.len()).rposition(|window| window == sub);
Ok(pos.map_or(PyInt::from(-1isize), |i| PyInt::from(start + i)))
}
#[pymethod]
fn flush(&self, options: FlushOptions, vm: &VirtualMachine) -> PyResult<()> {
let (offset, size) = options
.values(self.__len__())
.ok_or_else(|| vm.new_value_error("flush values out of range"))?;
if self.access == AccessMode::Read || self.access == AccessMode::Copy {
return Ok(());
}
match self.check_valid(vm)?.deref().as_ref().unwrap() {
MmapObj::Read(_mmap) => {}
MmapObj::Write(mmap) => {
mmap.flush_range(offset, size)
.map_err(|e| e.to_pyexception(vm))?;
}
}
Ok(())
}
#[cfg(all(unix, not(target_os = "redox")))]
#[pymethod]
fn madvise(&self, options: AdviseOptions, vm: &VirtualMachine) -> PyResult<()> {
let (option, start, length) = options.values(self.__len__(), vm)?;
let advice = validate_advice(vm, option)?;
let guard = self.check_valid(vm)?;
let mmap = guard.deref().as_ref().unwrap();
let ptr = match mmap {
MmapObj::Read(m) => m.as_ptr(),
MmapObj::Write(m) => m.as_ptr(),
};
// Apply madvise to the specified range (start, length)
let ptr_with_offset = unsafe { ptr.add(start) };
let result =
unsafe { libc::madvise(ptr_with_offset as *mut libc::c_void, length, advice) };
if result != 0 {
return Err(io::Error::last_os_error().to_pyexception(vm));
}
Ok(())
}
#[pymethod(name = "move")]
fn move_(
&self,
dest: PyIntRef,
src: PyIntRef,
cnt: PyIntRef,
vm: &VirtualMachine,
) -> PyResult<()> {
fn args(
dest: PyIntRef,
src: PyIntRef,
cnt: PyIntRef,
size: usize,
vm: &VirtualMachine,
) -> Option<(usize, usize, usize)> {
if dest.as_bigint().is_negative()
|| src.as_bigint().is_negative()
|| cnt.as_bigint().is_negative()
{
return None;
}
let dest = dest.try_to_primitive(vm).ok()?;
let src = src.try_to_primitive(vm).ok()?;
let cnt = cnt.try_to_primitive(vm).ok()?;
if size - dest < cnt || size - src < cnt {
return None;
}
Some((dest, src, cnt))
}
let size = self.__len__();
let (dest, src, cnt) = args(dest, src, cnt, size, vm)
.ok_or_else(|| vm.new_value_error("source, destination, or count out of range"))?;
let dest_end = dest + cnt;
let src_end = src + cnt;
self.try_writable(vm, |mmap| {
let src_buf = mmap[src..src_end].to_vec();
(&mut mmap[dest..dest_end])
.write(&src_buf)
.map_err(|e| e.to_pyexception(vm))?;
Ok(())
})?
}
#[pymethod]
fn read(&self, n: OptionalArg<PyObjectRef>, vm: &VirtualMachine) -> PyResult<PyBytesRef> {
let num_bytes = n
.map(|obj| {
let class = obj.class().to_owned();
obj.try_into_value::<Option<isize>>(vm).map_err(|_| {
vm.new_type_error(format!(
"read argument must be int or None, not {}",
class.name()
))
})
})
.transpose()?
.flatten();
let mmap = self.check_valid(vm)?;
let pos = self.pos();
let remaining = self.__len__().saturating_sub(pos);
let num_bytes = num_bytes
.filter(|&n| n >= 0 && (n as usize) <= remaining)
.map(|n| n as usize)
.unwrap_or(remaining);
let end_pos = pos + num_bytes;
let bytes = mmap.deref().as_ref().unwrap().as_slice()[pos..end_pos].to_vec();
let result = PyBytes::from(bytes).into_ref(&vm.ctx);
self.advance_pos(num_bytes);
Ok(result)
}
#[pymethod]
fn read_byte(&self, vm: &VirtualMachine) -> PyResult<PyIntRef> {
let pos = self.pos();
if pos >= self.__len__() {
return Err(vm.new_value_error("read byte out of range"));
}
let b = self.check_valid(vm)?.deref().as_ref().unwrap().as_slice()[pos];
self.advance_pos(1);
Ok(PyInt::from(b).into_ref(&vm.ctx))
}
#[pymethod]
fn readline(&self, vm: &VirtualMachine) -> PyResult<PyBytesRef> {
let pos = self.pos();