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authorKeuin <[email protected]>2023-07-07 00:33:12 +0800
committerKeuin <[email protected]>2023-07-07 00:33:12 +0800
commitc133daaba30d6c75eda2136a3c11682710f4562a (patch)
tree4c14b331b6870b852aff08fb71a4c222a777bda8 /common
parent76a7674dae069e0be15bed6af8450ad214f8dde2 (diff)
Refactor: remove unused code.
Diffstat (limited to 'common')
-rw-r--r--common/copy.go153
-rw-r--r--common/minmax.go27
2 files changed, 0 insertions, 180 deletions
diff --git a/common/copy.go b/common/copy.go
deleted file mode 100644
index 02e33a5..0000000
--- a/common/copy.go
+++ /dev/null
@@ -1,153 +0,0 @@
-package common
-
-/*
-Copied from https://ixday.github.io/post/golang-cancel-copy/
-*/
-
-import (
- "context"
- "fmt"
- "io"
- "os"
- "sync"
-)
-
-// CopyToFileWithBuffer copies data from io.Reader to os.File with given buffer and read chunk size.
-// The reader and writer may not be synchronized if any error occurs.
-// A block contains one or more chunks.
-// Every syscall reads at most one chunk.
-// Every disk-write writes at most one block.
-// The buffer is a ring contains one or more blocks.
-// The reader and file won't be closed.
-// If syncFile is set, the file will be synced after every read.
-// ringSize: how many blocks are in the buffer ring.
-func CopyToFileWithBuffer(
- ctx context.Context,
- out *os.File,
- in io.Reader,
- buffer []byte,
- syncFile bool,
- ringSize uint,
-) (written int64, err error) {
- var blkSize uint
- bufSize := uint(len(buffer))
- if bufSize%ringSize != 0 {
- err = fmt.Errorf("len(buffer) %% ringSize != 0")
- } else {
- blkSize = bufSize / ringSize
- }
-
- chWriteQue := make(chan uint, ringSize) // buffer write task queue
- chReadQue := make(chan uint, ringSize) // buffer read task queue
-
- // when reader and writer are stopped, this channel must have 2 elements
- chResult := make(chan error, 2)
-
- type task struct {
- Offset uint
- Length uint
- }
-
- chLastWrite := make(chan task, 1)
-
- rwCtx, cancelReadWrite := context.WithCancel(ctx)
-
- // wait reader and writer to finish
- wg := sync.WaitGroup{}
-
- // buffer reader
- // buffer -> file
- go func() {
- var err error
- wg.Add(1)
- defer wg.Done()
- defer func() {
- chResult <- err
- }()
- for {
- select {
- case <-rwCtx.Done():
- return
- default:
- // get the next available block to read from
- // this block is fully written in the buffer
- off := <-chReadQue
-
- // read the entire block to file
- n, err2 := out.Write(buffer[off : off+blkSize])
- if err2 != nil {
- // failed to write to the file
- // we can do nothing more than stop reading and writing
- err = fmt.Errorf("write error (%v byte written in this call): %w", n, err2)
- cancelReadWrite()
- return
- }
- }
- }
- }()
-
- // buffer writer
- // reader -> buffer
- go func() {
- var err error
- wg.Add(1)
- defer wg.Done()
- defer func() {
- chResult <- err
- }()
- for {
- select {
- case <-rwCtx.Done():
- chLastWrite <- task{
- Offset: 0,
- Length: 0,
- }
- return
- default:
- // get the next free block for writing
- off := <-chWriteQue // byte offset
-
- // fully fill the block
- nWritten := uint(0) // bytes written in this block currently
- for nWritten < blkSize {
- n, err := in.Read(buffer[off+nWritten : off+blkSize])
- nWritten += uint(n)
- if err != nil {
- // if we can't fully fill current block (e.g. EOF or IO error),
- // set nLeft to make the main goroutine handle that
- cancelReadWrite()
- err = fmt.Errorf("reader failed: %w", err)
- chLastWrite <- task{
- Offset: off,
- Length: nWritten, // bytes of valid data in the last incomplete block
- }
- return
- }
- }
- }
- }
- }()
-
- // init write tasks, all buffer blocks are available for writing initially
- for i := uint(0); i < bufSize; i += blkSize {
- chWriteQue <- i
- }
-
- wg.Wait()
-
- for i := 0; i < 2; i++ {
- if err2 := <-chResult; err2 != nil {
- err = err2
- return
- }
- }
-
- // write the remaining data
- last := <-chLastWrite
- if last.Length > 0 {
- var n int
- n, err = out.Write(buffer[last.Offset : last.Offset+last.Length])
- written += int64(n)
- }
- return
-}
diff --git a/common/minmax.go b/common/minmax.go
deleted file mode 100644
index b670887..0000000
--- a/common/minmax.go
+++ /dev/null
@@ -1,27 +0,0 @@
-package common
-
-/*
-Golang is a piece of shit. Its creators are paranoids.
-*/
-
-import (
- "golang.org/x/exp/constraints"
-)
-
-type Number interface {
- constraints.Integer | constraints.Float
-}
-
-func Min[T Number](t1 T, t2 T) T {
- if t1 < t2 {
- return t1
- }
- return t2
-}
-
-func Max[T Number](t1 T, t2 T) T {
- if t1 > t2 {
- return t1
- }
- return t2
-}