Developer Documentation
snappy-sinksource.cc
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28 
29 #include <string.h>
30 
31 #include "snappy-sinksource.h"
32 
33 namespace snappy {
34 
35 Source::~Source() { }
36 
37 Sink::~Sink() { }
38 
39 char* Sink::GetAppendBuffer(size_t length, char* scratch) {
40  return scratch;
41 }
42 
43 char* Sink::GetAppendBufferVariable(
44  size_t min_size, size_t desired_size_hint, char* scratch,
45  size_t scratch_size, size_t* allocated_size) {
46  *allocated_size = scratch_size;
47  return scratch;
48 }
49 
50 void Sink::AppendAndTakeOwnership(
51  char* bytes, size_t n,
52  void (*deleter)(void*, const char*, size_t),
53  void *deleter_arg) {
54  Append(bytes, n);
55  (*deleter)(deleter_arg, bytes, n);
56 }
57 
58 ByteArraySource::~ByteArraySource() { }
59 
60 size_t ByteArraySource::Available() const { return left_; }
61 
62 const char* ByteArraySource::Peek(size_t* len) {
63  *len = left_;
64  return ptr_;
65 }
66 
67 void ByteArraySource::Skip(size_t n) {
68  left_ -= n;
69  ptr_ += n;
70 }
71 
72 UncheckedByteArraySink::~UncheckedByteArraySink() { }
73 
74 void UncheckedByteArraySink::Append(const char* data, size_t n) {
75  // Do no copying if the caller filled in the result of GetAppendBuffer()
76  if (data != dest_) {
77  memcpy(dest_, data, n);
78  }
79  dest_ += n;
80 }
81 
82 char* UncheckedByteArraySink::GetAppendBuffer(size_t len, char* scratch) {
83  return dest_;
84 }
85 
86 void UncheckedByteArraySink::AppendAndTakeOwnership(
87  char* data, size_t n,
88  void (*deleter)(void*, const char*, size_t),
89  void *deleter_arg) {
90  if (data != dest_) {
91  memcpy(dest_, data, n);
92  (*deleter)(deleter_arg, data, n);
93  }
94  dest_ += n;
95 }
96 
97 char* UncheckedByteArraySink::GetAppendBufferVariable(
98  size_t min_size, size_t desired_size_hint, char* scratch,
99  size_t scratch_size, size_t* allocated_size) {
100  *allocated_size = desired_size_hint;
101  return dest_;
102 }
103 
104 } // namespace snappy