| // Copyright (C) 2015 The Android Open Source Project |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package memory |
| |
| import ( |
| "bufio" |
| "io" |
| |
| "android.googlesource.com/platform/tools/gpu/database" |
| "android.googlesource.com/platform/tools/gpu/log" |
| ) |
| |
| // Maximum number of bytes to buffer |
| const maxReadBuffer = 1024 |
| |
| // Reader returns a binary reader for the specified Slice. |
| func Reader(s Slice, d database.Database, l log.Logger) io.Reader { |
| c := s.Size() |
| return bufio.NewReaderSize(&reader{s, d, l, c, 0}, int(min(c, maxReadBuffer))) |
| } |
| |
| type reader struct { |
| s Slice |
| d database.Database |
| l log.Logger |
| r uint64 |
| o uint64 |
| } |
| |
| func (r *reader) Read(dst []byte) (n int, err error) { |
| if r.r == 0 { |
| return 0, io.EOF |
| } |
| c := min(uint64(len(dst)), r.r) |
| src, err := r.s.Slice(Range{Base: r.o, Size: c}).Get(r.d, r.l) |
| r.o += c |
| r.r -= c |
| return copy(dst, src), err |
| } |