• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 // Copyright (C) 2009-2011, International Business Machines
4 // Corporation and others. All Rights Reserved.
5 //
6 // Copyright 2007 Google Inc. All Rights Reserved.
7 // Author: sanjay@google.com (Sanjay Ghemawat)
8 
9 #include "unicode/utypes.h"
10 #include "unicode/bytestream.h"
11 #include "cmemory.h"
12 
13 U_NAMESPACE_BEGIN
14 
~ByteSink()15 ByteSink::~ByteSink() {}
16 
GetAppendBuffer(int32_t min_capacity,int32_t,char * scratch,int32_t scratch_capacity,int32_t * result_capacity)17 char* ByteSink::GetAppendBuffer(int32_t min_capacity,
18                                 int32_t /*desired_capacity_hint*/,
19                                 char* scratch, int32_t scratch_capacity,
20                                 int32_t* result_capacity) {
21   if (min_capacity < 1 || scratch_capacity < min_capacity) {
22     *result_capacity = 0;
23     return nullptr;
24   }
25   *result_capacity = scratch_capacity;
26   return scratch;
27 }
28 
Flush()29 void ByteSink::Flush() {}
30 
CheckedArrayByteSink(char * outbuf,int32_t capacity)31 CheckedArrayByteSink::CheckedArrayByteSink(char* outbuf, int32_t capacity)
32     : outbuf_(outbuf), capacity_(capacity < 0 ? 0 : capacity),
33       size_(0), appended_(0), overflowed_(false) {
34 }
35 
~CheckedArrayByteSink()36 CheckedArrayByteSink::~CheckedArrayByteSink() {}
37 
Reset()38 CheckedArrayByteSink& CheckedArrayByteSink::Reset() {
39   size_ = appended_ = 0;
40   overflowed_ = false;
41   return *this;
42 }
43 
Append(const char * bytes,int32_t n)44 void CheckedArrayByteSink::Append(const char* bytes, int32_t n) {
45   if (n <= 0) {
46     return;
47   }
48   if (n > (INT32_MAX - appended_)) {
49     // TODO: Report as integer overflow, not merely buffer overflow.
50     appended_ = INT32_MAX;
51     overflowed_ = true;
52     return;
53   }
54   appended_ += n;
55   int32_t available = capacity_ - size_;
56   if (n > available) {
57     n = available;
58     overflowed_ = true;
59   }
60   if (n > 0 && bytes != (outbuf_ + size_)) {
61     uprv_memcpy(outbuf_ + size_, bytes, n);
62   }
63   size_ += n;
64 }
65 
GetAppendBuffer(int32_t min_capacity,int32_t,char * scratch,int32_t scratch_capacity,int32_t * result_capacity)66 char* CheckedArrayByteSink::GetAppendBuffer(int32_t min_capacity,
67                                             int32_t /*desired_capacity_hint*/,
68                                             char* scratch,
69                                             int32_t scratch_capacity,
70                                             int32_t* result_capacity) {
71   if (min_capacity < 1 || scratch_capacity < min_capacity) {
72     *result_capacity = 0;
73     return nullptr;
74   }
75   int32_t available = capacity_ - size_;
76   if (available >= min_capacity) {
77     *result_capacity = available;
78     return outbuf_ + size_;
79   } else {
80     *result_capacity = scratch_capacity;
81     return scratch;
82   }
83 }
84 
85 U_NAMESPACE_END
86