1aaa100bdb
* add alloc/free_transfer_and_buffer. Manages the buffer memory on the C side. * switch libusb.go to use the new alloc/free_transfer_and_buffer. Add a new buffer() call to get access to the allocated buffer as a Go slice. * Fake USB transfer uses the new alloc/free/buffer interface. * Switch to the new libusb.alloc signature, where libusb owns the buffer. * newUSBTransfer now allocates a separate buffer, do a copy on endpoint.transfer. * newUSBTransfer will now allocate it's own buffer. * Enable autodetach in rawread.
45 lines
1.5 KiB
Go
45 lines
1.5 KiB
Go
// Copyright 2017 the gousb Authors. All rights reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package gousb
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func (e *endpoint) newStream(size, count int, submit bool) (*stream, error) {
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var ts []transferIntf
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for i := 0; i < count; i++ {
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t, err := newUSBTransfer(e.h, &e.Desc, size, e.Timeout)
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if err != nil {
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for _, t := range ts {
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t.free()
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}
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return nil, err
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}
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ts = append(ts, t)
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}
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return newStream(ts, submit), nil
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}
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// NewStream prepares a new read stream that will keep reading data from the
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// endpoint until closed.
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// Size defines a buffer size for a single read transaction and count
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// defines how many transactions should be active at any time.
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// By keeping multiple transfers active at the same time, a Stream reduces
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// the latency between subsequent transfers and increases reading throughput.
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func (e *InEndpoint) NewStream(size, count int) (*ReadStream, error) {
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s, err := e.newStream(size, count, true)
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if err != nil {
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return nil, err
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}
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return &ReadStream{s}, nil
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}
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