mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer-rs.git
synced 2024-05-14 06:12:40 +00:00
617 lines
21 KiB
Rust
617 lines
21 KiB
Rust
// Take a look at the license at the top of the repository in the LICENSE file.
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use std::{fmt, io, marker::PhantomData, mem, ptr, u64, usize};
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use crate::{
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buffer::{Readable, Writable},
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Buffer, BufferRef,
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};
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pub struct BufferCursor<T> {
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buffer: Option<Buffer>,
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size: u64,
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num_mem: u32,
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cur_mem_idx: u32,
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cur_offset: u64,
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cur_mem_offset: usize,
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map_info: ffi::GstMapInfo,
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phantom: PhantomData<T>,
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}
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pub struct BufferRefCursor<T> {
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buffer: T,
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size: u64,
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num_mem: u32,
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cur_mem_idx: u32,
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cur_offset: u64,
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cur_mem_offset: usize,
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map_info: ffi::GstMapInfo,
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}
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macro_rules! define_seek_impl(
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($get_buffer_ref:expr) => {
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fn seek(&mut self, pos: io::SeekFrom) -> Result<u64, io::Error> {
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match pos {
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io::SeekFrom::Start(off) => {
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self.cur_offset = std::cmp::min(self.size, off);
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}
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io::SeekFrom::End(off) if off <= 0 => {
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self.cur_offset = self.size;
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}
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io::SeekFrom::End(off) => {
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self.cur_offset = self.size.checked_sub(off as u64).ok_or_else(|| {
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io::Error::new(io::ErrorKind::InvalidInput, "Seek before start of buffer")
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})?;
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}
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io::SeekFrom::Current(std::i64::MIN) => {
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return Err(io::Error::new(
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io::ErrorKind::InvalidInput,
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"Seek before start of buffer",
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));
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}
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io::SeekFrom::Current(off) => {
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if off <= 0 {
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self.cur_offset =
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self.cur_offset.checked_sub((-off) as u64).ok_or_else(|| {
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io::Error::new(
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io::ErrorKind::InvalidInput,
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"Seek before start of buffer",
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)
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})?;
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} else {
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self.cur_offset = std::cmp::min(
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self.size,
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self.cur_offset.checked_add(off as u64).unwrap_or(self.size),
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);
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}
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}
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}
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// Work around lifetime annotation issues with closures
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let buffer_ref: fn(&Self) -> &BufferRef = $get_buffer_ref;
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let (range, skip) = buffer_ref(self)
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.find_memory(self.cur_offset as usize..)
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.expect("Failed to find memory");
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if range.start != self.cur_mem_idx && !self.map_info.memory.is_null() {
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unsafe {
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ffi::gst_memory_unmap(self.map_info.memory, &mut self.map_info);
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self.map_info.memory = ptr::null_mut();
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}
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}
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self.cur_mem_idx = range.start;
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self.cur_mem_offset = skip;
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Ok(self.cur_offset)
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}
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// Once stabilized
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// fn stream_len(&mut self) -> Result<u64, io::Error> {
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// Ok(self.size)
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// }
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//
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// fn stream_position(&mut self) -> Result<u64, io::Error> {
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// Ok(self.current_offset)
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// }
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}
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);
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macro_rules! define_read_write_fn_impl(
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($self:ident, $data:ident, $data_type:ty, $get_buffer_ref:expr, $map_flags:path, $copy:expr, $split:expr) => {
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#[allow(clippy::redundant_closure_call)]
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{
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let mut copied = 0;
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while !$data.is_empty() && $self.cur_mem_idx < $self.num_mem {
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// Map memory if needed. cur_mem_idx, cur_mem_offset and cur_offset are required to be
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// set correctly here already (from constructor, seek and the bottom of the loop)
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if $self.map_info.memory.is_null() {
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unsafe {
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// Work around lifetime annotation issues with closures
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let buffer_ref: fn(&Self) -> &BufferRef = $get_buffer_ref;
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let memory = ffi::gst_buffer_peek_memory(
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buffer_ref($self).as_mut_ptr(),
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$self.cur_mem_idx,
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);
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debug_assert!(!memory.is_null());
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if ffi::gst_memory_map(memory, &mut $self.map_info, $map_flags)
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== glib::ffi::GFALSE
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{
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return Err(io::Error::new(
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io::ErrorKind::InvalidData,
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"Failed to map memory readable",
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));
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}
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}
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debug_assert!($self.cur_mem_offset < $self.map_info.size);
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}
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debug_assert!(!$self.map_info.memory.is_null());
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// Copy all data we can currently copy
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let data_left = $self.map_info.size - $self.cur_mem_offset;
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let to_copy = std::cmp::min($data.len(), data_left);
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$copy(&$self.map_info, $self.cur_mem_offset, $data, to_copy);
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copied += to_copy;
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$self.cur_offset += to_copy as u64;
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$self.cur_mem_offset += to_copy;
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// Work around lifetime annotation issues with closures
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let split: fn($data_type, usize) -> $data_type = $split;
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#[allow(clippy::redundant_closure_call)]
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{
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$data = split($data, to_copy);
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}
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// If we're at the end of the current memory, unmap and advance to the next memory
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if $self.cur_mem_offset == $self.map_info.size {
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unsafe {
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ffi::gst_memory_unmap($self.map_info.memory, &mut $self.map_info);
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}
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$self.map_info.memory = ptr::null_mut();
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$self.cur_mem_idx += 1;
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$self.cur_mem_offset = 0;
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}
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}
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Ok(copied)
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}}
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);
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macro_rules! define_read_impl(
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($get_buffer_ref:expr) => {
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fn read(&mut self, mut data: &mut [u8]) -> Result<usize, io::Error> {
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define_read_write_fn_impl!(
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self,
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data,
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&mut [u8],
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$get_buffer_ref,
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ffi::GST_MAP_READ,
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|map_info: &ffi::GstMapInfo, off, data: &mut [u8], to_copy| unsafe {
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ptr::copy_nonoverlapping(
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(map_info.data as *const u8).add(off),
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data.as_mut_ptr(),
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to_copy,
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);
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},
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|data, to_copy| &mut data[to_copy..]
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)
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}
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}
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);
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macro_rules! define_write_impl(
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($get_buffer_ref:expr) => {
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fn write(&mut self, mut data: &[u8]) -> Result<usize, io::Error> {
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define_read_write_fn_impl!(
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self,
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data,
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&[u8],
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$get_buffer_ref,
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ffi::GST_MAP_WRITE,
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|map_info: &ffi::GstMapInfo, off, data: &[u8], to_copy| unsafe {
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ptr::copy_nonoverlapping(
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data.as_ptr(),
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(map_info.data as *mut u8).add(off),
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to_copy,
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);
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},
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|data, to_copy| &data[to_copy..]
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)
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}
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fn flush(&mut self) -> Result<(), io::Error> {
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if !self.map_info.memory.is_null() {
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unsafe {
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ffi::gst_memory_unmap(self.map_info.memory, &mut self.map_info);
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self.map_info.memory = ptr::null_mut();
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}
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}
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Ok(())
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}
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}
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);
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impl<T> fmt::Debug for BufferCursor<T> {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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f.debug_struct("BufferCursor")
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.field("buffer", &self.buffer)
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.field("size", &self.size)
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.field("num_mem", &self.num_mem)
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.field("cur_mem_idx", &self.cur_mem_idx)
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.field("cur_offset", &self.cur_offset)
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.field("cur_mem_offset", &self.cur_mem_offset)
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.field("map_info", &self.map_info)
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.finish()
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}
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}
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impl<T> Drop for BufferCursor<T> {
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fn drop(&mut self) {
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if !self.map_info.memory.is_null() {
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unsafe {
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ffi::gst_memory_unmap(self.map_info.memory, &mut self.map_info);
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}
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}
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}
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}
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impl io::Read for BufferCursor<Readable> {
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define_read_impl!(|s| s.buffer.as_ref().unwrap());
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}
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impl io::Write for BufferCursor<Writable> {
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define_write_impl!(|s| s.buffer.as_ref().unwrap());
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}
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impl<T> io::Seek for BufferCursor<T> {
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define_seek_impl!(|s| s.buffer.as_ref().unwrap());
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}
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impl<T> BufferCursor<T> {
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pub fn stream_len(&mut self) -> Result<u64, io::Error> {
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Ok(self.size)
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}
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pub fn stream_position(&mut self) -> Result<u64, io::Error> {
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Ok(self.cur_offset)
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}
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#[doc(alias = "get_buffer")]
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pub fn buffer(&self) -> &BufferRef {
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self.buffer.as_ref().unwrap().as_ref()
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}
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pub fn into_buffer(mut self) -> Buffer {
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self.buffer.take().unwrap()
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}
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}
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impl BufferCursor<Readable> {
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pub(crate) fn new_readable(buffer: Buffer) -> BufferCursor<Readable> {
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skip_assert_initialized!();
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let size = buffer.size() as u64;
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let num_mem = buffer.n_memory();
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BufferCursor {
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buffer: Some(buffer),
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size,
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num_mem,
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cur_mem_idx: 0,
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cur_offset: 0,
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cur_mem_offset: 0,
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map_info: unsafe { mem::zeroed() },
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phantom: PhantomData,
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}
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}
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pub fn buffer_owned(&self) -> Buffer {
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self.buffer.as_ref().unwrap().clone()
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}
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}
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impl BufferCursor<Writable> {
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pub(crate) fn new_writable(buffer: Buffer) -> Result<BufferCursor<Writable>, glib::BoolError> {
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skip_assert_initialized!();
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if !buffer.is_writable() || !buffer.is_all_memory_writable() {
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return Err(glib::bool_error!("Not all memories are writable"));
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}
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let size = buffer.size() as u64;
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let num_mem = buffer.n_memory();
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Ok(BufferCursor {
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buffer: Some(buffer),
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size,
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num_mem,
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cur_mem_idx: 0,
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cur_offset: 0,
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cur_mem_offset: 0,
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map_info: unsafe { mem::zeroed() },
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phantom: PhantomData,
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})
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}
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}
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unsafe impl<T> Send for BufferCursor<T> {}
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unsafe impl<T> Sync for BufferCursor<T> {}
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impl<T: fmt::Debug> fmt::Debug for BufferRefCursor<T> {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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f.debug_struct("BufferRefCursor")
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.field("buffer", &self.buffer)
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.field("size", &self.size)
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.field("num_mem", &self.num_mem)
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.field("cur_mem_idx", &self.cur_mem_idx)
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.field("cur_offset", &self.cur_offset)
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.field("cur_mem_offset", &self.cur_mem_offset)
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.field("map_info", &self.map_info)
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.finish()
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}
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}
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impl<T> Drop for BufferRefCursor<T> {
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fn drop(&mut self) {
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if !self.map_info.memory.is_null() {
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unsafe {
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ffi::gst_memory_unmap(self.map_info.memory, &mut self.map_info);
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}
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}
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}
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}
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impl<'a> io::Read for BufferRefCursor<&'a BufferRef> {
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define_read_impl!(|s| s.buffer);
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}
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impl<'a> io::Write for BufferRefCursor<&'a mut BufferRef> {
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define_write_impl!(|s| s.buffer);
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}
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impl<'a> io::Seek for BufferRefCursor<&'a BufferRef> {
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define_seek_impl!(|s| s.buffer);
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}
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impl<'a> io::Seek for BufferRefCursor<&'a mut BufferRef> {
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define_seek_impl!(|s| s.buffer);
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}
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impl<T> BufferRefCursor<T> {
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pub fn stream_len(&mut self) -> Result<u64, io::Error> {
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Ok(self.size)
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}
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pub fn stream_position(&mut self) -> Result<u64, io::Error> {
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Ok(self.cur_offset)
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}
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}
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impl<'a> BufferRefCursor<&'a BufferRef> {
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#[doc(alias = "get_buffer")]
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pub fn buffer(&self) -> &BufferRef {
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self.buffer
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}
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pub(crate) fn new_readable(buffer: &'a BufferRef) -> BufferRefCursor<&'a BufferRef> {
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skip_assert_initialized!();
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let size = buffer.size() as u64;
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let num_mem = buffer.n_memory();
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BufferRefCursor {
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buffer,
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size,
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num_mem,
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cur_mem_idx: 0,
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cur_offset: 0,
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cur_mem_offset: 0,
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map_info: unsafe { mem::zeroed() },
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}
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}
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}
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impl<'a> BufferRefCursor<&'a mut BufferRef> {
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#[doc(alias = "get_buffer")]
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pub fn buffer(&self) -> &BufferRef {
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self.buffer
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}
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pub(crate) fn new_writable(
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buffer: &'a mut BufferRef,
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) -> Result<BufferRefCursor<&'a mut BufferRef>, glib::BoolError> {
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skip_assert_initialized!();
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if !buffer.is_all_memory_writable() {
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return Err(glib::bool_error!("Not all memories are writable"));
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}
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let size = buffer.size() as u64;
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let num_mem = buffer.n_memory();
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Ok(BufferRefCursor {
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buffer,
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size,
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num_mem,
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cur_mem_idx: 0,
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cur_offset: 0,
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cur_mem_offset: 0,
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map_info: unsafe { mem::zeroed() },
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})
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}
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}
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unsafe impl<T> Send for BufferRefCursor<T> {}
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unsafe impl<T> Sync for BufferRefCursor<T> {}
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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#[allow(clippy::cognitive_complexity)]
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fn test_buffer_cursor() {
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use std::io::{self, Read, Seek, Write};
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crate::init().unwrap();
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let mut buffer = Buffer::new();
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{
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let buffer = buffer.get_mut().unwrap();
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buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
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buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
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buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
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buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
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buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 10]));
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}
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assert!(buffer.is_all_memory_writable());
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assert_eq!(buffer.n_memory(), 5);
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assert_eq!(buffer.size(), 30);
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let mut cursor = buffer.into_cursor_writable().unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 0);
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cursor.write_all(b"01234567").unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 8);
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cursor.write_all(b"890123").unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 14);
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cursor.write_all(b"456").unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 17);
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cursor.write_all(b"78901234567").unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 28);
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cursor.write_all(b"89").unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 30);
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assert!(cursor.write_all(b"0").is_err());
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assert_eq!(cursor.seek(io::SeekFrom::Start(5)).unwrap(), 5);
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assert_eq!(cursor.stream_position().unwrap(), 5);
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cursor.write_all(b"A").unwrap();
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assert_eq!(cursor.seek(io::SeekFrom::End(5)).unwrap(), 25);
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assert_eq!(cursor.stream_position().unwrap(), 25);
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cursor.write_all(b"B").unwrap();
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assert_eq!(cursor.seek(io::SeekFrom::Current(-1)).unwrap(), 25);
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assert_eq!(cursor.stream_position().unwrap(), 25);
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cursor.write_all(b"C").unwrap();
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assert_eq!(cursor.seek(io::SeekFrom::Current(1)).unwrap(), 27);
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assert_eq!(cursor.stream_position().unwrap(), 27);
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cursor.write_all(b"D").unwrap();
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let buffer = cursor.into_buffer();
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let mut cursor = buffer.into_cursor_readable();
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let mut data = [0; 30];
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assert_eq!(cursor.stream_position().unwrap(), 0);
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cursor.read_exact(&mut data[0..7]).unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 7);
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assert_eq!(&data[0..7], b"01234A6");
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cursor.read_exact(&mut data[0..5]).unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 12);
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assert_eq!(&data[0..5], b"78901");
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cursor.read_exact(&mut data[0..10]).unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 22);
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assert_eq!(&data[0..10], b"2345678901");
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cursor.read_exact(&mut data[0..8]).unwrap();
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assert_eq!(cursor.stream_position().unwrap(), 30);
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assert_eq!(&data[0..8], b"234C6D89");
|
|
assert!(cursor.read_exact(&mut data[0..1]).is_err());
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Start(5)).unwrap(), 5);
|
|
assert_eq!(cursor.stream_position().unwrap(), 5);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"A");
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::End(5)).unwrap(), 25);
|
|
assert_eq!(cursor.stream_position().unwrap(), 25);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"C");
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Current(-1)).unwrap(), 25);
|
|
assert_eq!(cursor.stream_position().unwrap(), 25);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"C");
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Current(1)).unwrap(), 27);
|
|
assert_eq!(cursor.stream_position().unwrap(), 27);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"D");
|
|
}
|
|
|
|
#[test]
|
|
#[allow(clippy::cognitive_complexity)]
|
|
fn test_buffer_cursor_ref() {
|
|
use std::io::{self, Read, Seek, Write};
|
|
|
|
crate::init().unwrap();
|
|
|
|
let mut buffer = Buffer::new();
|
|
{
|
|
let buffer = buffer.get_mut().unwrap();
|
|
buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
|
|
buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
|
|
buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
|
|
buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 5]));
|
|
buffer.append_memory(crate::Memory::from_mut_slice(vec![0; 10]));
|
|
}
|
|
|
|
assert!(buffer.is_all_memory_writable());
|
|
assert_eq!(buffer.n_memory(), 5);
|
|
assert_eq!(buffer.size(), 30);
|
|
|
|
{
|
|
let buffer = buffer.get_mut().unwrap();
|
|
|
|
let mut cursor = buffer.as_cursor_writable().unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 0);
|
|
cursor.write_all(b"01234567").unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 8);
|
|
cursor.write_all(b"890123").unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 14);
|
|
cursor.write_all(b"456").unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 17);
|
|
cursor.write_all(b"78901234567").unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 28);
|
|
cursor.write_all(b"89").unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 30);
|
|
assert!(cursor.write_all(b"0").is_err());
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Start(5)).unwrap(), 5);
|
|
assert_eq!(cursor.stream_position().unwrap(), 5);
|
|
cursor.write_all(b"A").unwrap();
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::End(5)).unwrap(), 25);
|
|
assert_eq!(cursor.stream_position().unwrap(), 25);
|
|
cursor.write_all(b"B").unwrap();
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Current(-1)).unwrap(), 25);
|
|
assert_eq!(cursor.stream_position().unwrap(), 25);
|
|
cursor.write_all(b"C").unwrap();
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Current(1)).unwrap(), 27);
|
|
assert_eq!(cursor.stream_position().unwrap(), 27);
|
|
cursor.write_all(b"D").unwrap();
|
|
}
|
|
|
|
let mut cursor = buffer.as_cursor_readable();
|
|
let mut data = [0; 30];
|
|
|
|
assert_eq!(cursor.stream_position().unwrap(), 0);
|
|
cursor.read_exact(&mut data[0..7]).unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 7);
|
|
assert_eq!(&data[0..7], b"01234A6");
|
|
cursor.read_exact(&mut data[0..5]).unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 12);
|
|
assert_eq!(&data[0..5], b"78901");
|
|
cursor.read_exact(&mut data[0..10]).unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 22);
|
|
assert_eq!(&data[0..10], b"2345678901");
|
|
cursor.read_exact(&mut data[0..8]).unwrap();
|
|
assert_eq!(cursor.stream_position().unwrap(), 30);
|
|
assert_eq!(&data[0..8], b"234C6D89");
|
|
assert!(cursor.read_exact(&mut data[0..1]).is_err());
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Start(5)).unwrap(), 5);
|
|
assert_eq!(cursor.stream_position().unwrap(), 5);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"A");
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::End(5)).unwrap(), 25);
|
|
assert_eq!(cursor.stream_position().unwrap(), 25);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"C");
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Current(-1)).unwrap(), 25);
|
|
assert_eq!(cursor.stream_position().unwrap(), 25);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"C");
|
|
|
|
assert_eq!(cursor.seek(io::SeekFrom::Current(1)).unwrap(), 27);
|
|
assert_eq!(cursor.stream_position().unwrap(), 27);
|
|
cursor.read_exact(&mut data[0..1]).unwrap();
|
|
assert_eq!(&data[0..1], b"D");
|
|
}
|
|
}
|