Documentation
¶
Overview ¶
Package libatbus_buffer provides buffer management utilities for libatbus. This file implements StaticBufferBlock, a Go port of C++ static_buffer_block.
Index ¶
- Constants
- Variables
- func FullSize(s int) int
- func HeadSize(s int) int
- func MimallocPaddingSize(originSize int) int
- func PaddingSize(s int) int
- func ReadVint(data []byte) (uint64, int)
- func VintEncodedSize(value uint64) int
- func WriteVint(value uint64, data []byte) int
- type BufferBlock
- func (b *BufferBlock) Clone() *BufferBlock
- func (b *BufferBlock) Data() []byte
- func (b *BufferBlock) Pop(s int) []byte
- func (b *BufferBlock) RawData() []byte
- func (b *BufferBlock) RawSize() int
- func (b *BufferBlock) Reset()
- func (b *BufferBlock) SetUsed(used int)
- func (b *BufferBlock) Size() int
- func (b *BufferBlock) Used() int
- type BufferManager
- func (m *BufferManager) Back() *BufferBlock
- func (m *BufferManager) BackData() (data []byte, nread, nwrite int, err error)
- func (m *BufferManager) Count() int
- func (m *BufferManager) Empty() bool
- func (m *BufferManager) ForEach(fn func(block *BufferBlock) bool)
- func (m *BufferManager) Front() *BufferBlock
- func (m *BufferManager) FrontData() (data []byte, nread, nwrite int, err error)
- func (m *BufferManager) IsDynamicMode() bool
- func (m *BufferManager) IsStaticMode() bool
- func (m *BufferManager) Limit() Limit
- func (m *BufferManager) MergeBack(size int) (data []byte, err error)
- func (m *BufferManager) MergeFront(size int) (data []byte, err error)
- func (m *BufferManager) PopBack(size int, freeUnwritable bool) error
- func (m *BufferManager) PopFront(size int, freeUnwritable bool) error
- func (m *BufferManager) PushBack(size int) (data []byte, err error)
- func (m *BufferManager) PushFront(size int) (data []byte, err error)
- func (m *BufferManager) Reset()
- func (m *BufferManager) SetLimit(maxSize, maxNumber int) bool
- func (m *BufferManager) SetMode(maxSize, maxNumber int)
- type Limit
- type StaticBufferBlock
- func (s *StaticBufferBlock) Data() []byte
- func (s *StaticBufferBlock) IsEmpty() bool
- func (s *StaticBufferBlock) MaxSpan() []byte
- func (s *StaticBufferBlock) Reset()
- func (s *StaticBufferBlock) SetUsed(used int)
- func (s *StaticBufferBlock) Size() int
- func (s *StaticBufferBlock) Used() int
- func (s *StaticBufferBlock) UsedSpan() []byte
- func (s *StaticBufferBlock) Write(data []byte) int
- func (s *StaticBufferBlock) WriteAt(offset int, data []byte) int
Constants ¶
const DataAlignSize = 8
DataAlignSize is the alignment size for buffer data
Variables ¶
var ( ErrSuccess = errors.New("success") ErrNoData = errors.New("no data available") ErrBuffLimit = errors.New("buffer limit reached") ErrMalloc = errors.New("memory allocation failed") ErrInvalidArg = errors.New("invalid argument") )
Error codes
Functions ¶
func HeadSize ¶
HeadSize returns the overhead size for a buffer block header In Go, we don't need actual header storage since we use struct fields, but we keep this for compatibility with size calculations
func MimallocPaddingSize ¶
MimallocPaddingSize calculates padded size following mimalloc-style size class patterns. This helps reduce memory fragmentation and improve malloc efficiency.
func PaddingSize ¶
PaddingSize calculates the padded size aligned to DataAlignSize
func ReadVint ¶
ReadVint reads a variable-length encoded integer from the buffer. Each byte uses 7 bits for data and the highest bit (0x80) indicates continuation. Returns the decoded value and the number of bytes consumed. If the buffer is empty or truncated (continuation bit set but no more data), returns (0, 0).
func VintEncodedSize ¶
VintEncodedSize returns the number of bytes needed to encode the given value.
Types ¶
type BufferBlock ¶
type BufferBlock struct {
// contains filtered or unexported fields
}
BufferBlock represents a buffer block with size and used tracking It manages a slice of bytes with a "used" offset for pop operations
func NewBufferBlock ¶
func NewBufferBlock(size int) *BufferBlock
NewBufferBlock creates a new BufferBlock with the specified size
func NewBufferBlockFromSlice ¶
func NewBufferBlockFromSlice(data []byte) *BufferBlock
NewBufferBlockFromSlice creates a BufferBlock wrapping an existing slice
func (*BufferBlock) Clone ¶
func (b *BufferBlock) Clone() *BufferBlock
Clone creates a deep copy of the buffer block
func (*BufferBlock) Data ¶
func (b *BufferBlock) Data() []byte
Data returns the unread portion of the buffer (after used offset)
func (*BufferBlock) Pop ¶
func (b *BufferBlock) Pop(s int) []byte
Pop advances the used pointer by s bytes, reducing the available size Returns the new data slice after the pop
func (*BufferBlock) RawData ¶
func (b *BufferBlock) RawData() []byte
RawData returns the entire buffer from the beginning
func (*BufferBlock) RawSize ¶
func (b *BufferBlock) RawSize() int
RawSize returns the total size of the buffer
func (*BufferBlock) SetUsed ¶
func (b *BufferBlock) SetUsed(used int)
SetUsed sets the used counter directly
func (*BufferBlock) Size ¶
func (b *BufferBlock) Size() int
Size returns the remaining size (total - used)
func (*BufferBlock) Used ¶
func (b *BufferBlock) Used() int
Used returns how many bytes have been popped
type BufferManager ¶
type BufferManager struct {
// contains filtered or unexported fields
}
BufferManager manages a collection of buffer blocks It can operate in dynamic mode (using linked list) or static mode (using circular buffer)
func NewBufferManager ¶
func NewBufferManager() *BufferManager
NewBufferManager creates a new buffer manager in dynamic mode
func (*BufferManager) Back ¶
func (m *BufferManager) Back() *BufferBlock
Back returns the last buffer block
func (*BufferManager) BackData ¶
func (m *BufferManager) BackData() (data []byte, nread, nwrite int, err error)
BackData returns the data pointer, read size, and write size of the back block
func (*BufferManager) Count ¶
func (m *BufferManager) Count() int
Count returns the number of buffer blocks
func (*BufferManager) Empty ¶
func (m *BufferManager) Empty() bool
Empty returns true if there are no buffer blocks
func (*BufferManager) ForEach ¶
func (m *BufferManager) ForEach(fn func(block *BufferBlock) bool)
ForEach iterates over all buffer blocks
func (*BufferManager) Front ¶
func (m *BufferManager) Front() *BufferBlock
Front returns the first buffer block
func (*BufferManager) FrontData ¶
func (m *BufferManager) FrontData() (data []byte, nread, nwrite int, err error)
FrontData returns the data pointer, read size, and write size of the front block
func (*BufferManager) IsDynamicMode ¶
func (m *BufferManager) IsDynamicMode() bool
IsDynamicMode returns true if the manager is in dynamic mode
func (*BufferManager) IsStaticMode ¶
func (m *BufferManager) IsStaticMode() bool
IsStaticMode returns true if the manager is in static mode
func (*BufferManager) Limit ¶
func (m *BufferManager) Limit() Limit
Limit returns the current limit configuration
func (*BufferManager) MergeBack ¶
func (m *BufferManager) MergeBack(size int) (data []byte, err error)
MergeBack extends the back block by additional size
func (*BufferManager) MergeFront ¶
func (m *BufferManager) MergeFront(size int) (data []byte, err error)
MergeFront extends the front block by additional size
func (*BufferManager) PopBack ¶
func (m *BufferManager) PopBack(size int, freeUnwritable bool) error
PopBack pops bytes from the back block
func (*BufferManager) PopFront ¶
func (m *BufferManager) PopFront(size int, freeUnwritable bool) error
PopFront pops bytes from the front block
func (*BufferManager) PushBack ¶
func (m *BufferManager) PushBack(size int) (data []byte, err error)
PushBack allocates a new block at the back and returns the data slice
func (*BufferManager) PushFront ¶
func (m *BufferManager) PushFront(size int) (data []byte, err error)
PushFront allocates a new block at the front and returns the data slice
func (*BufferManager) Reset ¶
func (m *BufferManager) Reset()
Reset clears all data and returns to initial state
func (*BufferManager) SetLimit ¶
func (m *BufferManager) SetLimit(maxSize, maxNumber int) bool
SetLimit sets limits when in dynamic mode Returns true on success, false if in static mode
func (*BufferManager) SetMode ¶
func (m *BufferManager) SetMode(maxSize, maxNumber int)
SetMode switches to static mode with a fixed buffer size and max number of blocks
type Limit ¶
type Limit struct {
CostNumber int // Current number of blocks
CostSize int // Current total size used
LimitNumber int // Maximum number of blocks (0 = unlimited)
LimitSize int // Maximum total size (0 = unlimited)
}
Limit tracks the buffer usage limits and current costs
type StaticBufferBlock ¶
type StaticBufferBlock struct {
// contains filtered or unexported fields
}
StaticBufferBlock is a buffer block designed for temporary buffer allocation. It tracks the total allocated size and the used portion.
This is the Go equivalent of C++ static_buffer_block from libatbus. Unlike the C++ version which uses unique_ptr<unsigned char[]>, we use a []byte slice.
func AllocateTemporaryBufferBlock ¶
func AllocateTemporaryBufferBlock(originSize int) *StaticBufferBlock
AllocateTemporaryBufferBlock allocates a temporary buffer with size padding.
func NewStaticBufferBlock ¶
func NewStaticBufferBlock(size int) *StaticBufferBlock
NewStaticBufferBlock creates a new StaticBufferBlock with the given size. The buffer is allocated but used is set to 0.
func NewStaticBufferBlockFromData ¶
func NewStaticBufferBlockFromData(data []byte) *StaticBufferBlock
NewStaticBufferBlockFromData creates a StaticBufferBlock from existing data. The data is copied (not referenced) to avoid aliasing issues.
func NewStaticBufferBlockWithUsed ¶
func NewStaticBufferBlockWithUsed(size, used int) *StaticBufferBlock
NewStaticBufferBlockWithUsed creates a StaticBufferBlock with specified size and used.
func (*StaticBufferBlock) Data ¶
func (s *StaticBufferBlock) Data() []byte
Data returns the underlying buffer data pointer (up to size).
func (*StaticBufferBlock) IsEmpty ¶
func (s *StaticBufferBlock) IsEmpty() bool
IsEmpty returns true if no bytes are used.
func (*StaticBufferBlock) MaxSpan ¶
func (s *StaticBufferBlock) MaxSpan() []byte
MaxSpan returns a slice of the entire allocated buffer.
func (*StaticBufferBlock) Reset ¶
func (s *StaticBufferBlock) Reset()
Reset clears the used counter to 0 (does not zero the buffer).
func (*StaticBufferBlock) SetUsed ¶
func (s *StaticBufferBlock) SetUsed(used int)
SetUsed sets the used size, clamped to [0, size].
func (*StaticBufferBlock) Size ¶
func (s *StaticBufferBlock) Size() int
Size returns the total allocated size of the buffer.
func (*StaticBufferBlock) Used ¶
func (s *StaticBufferBlock) Used() int
Used returns the number of bytes actually used.
func (*StaticBufferBlock) UsedSpan ¶
func (s *StaticBufferBlock) UsedSpan() []byte
UsedSpan returns a slice of only the used portion of the buffer.
func (*StaticBufferBlock) Write ¶
func (s *StaticBufferBlock) Write(data []byte) int
Write appends data to the buffer, updating used. Returns the number of bytes written.
Source Files