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
13U_NAMESPACE_BEGIN
14
15ByteSink::~ByteSink() {}
16
17char* 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
29void ByteSink::Flush() {}
30
31CheckedArrayByteSink::CheckedArrayByteSink(char* outbuf, int32_t capacity)
32 : outbuf_(outbuf), capacity_(capacity < 0 ? 0 : capacity),
33 size_(0), appended_(0), overflowed_(false) {
34}
35
36CheckedArrayByteSink::~CheckedArrayByteSink() {}
37
38CheckedArrayByteSink& CheckedArrayByteSink::Reset() {
39 size_ = appended_ = 0;
40 overflowed_ = false;
41 return *this;
42}
43
44void 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
66char* 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
85U_NAMESPACE_END
86