1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2008 Google Inc. All rights reserved.
3 // https://developers.google.com/protocol-buffers/
4 //
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are
7 // met:
8 //
9 // * Redistributions of source code must retain the above copyright
10 // notice, this list of conditions and the following disclaimer.
11 // * Redistributions in binary form must reproduce the above
12 // copyright notice, this list of conditions and the following disclaimer
13 // in the documentation and/or other materials provided with the
14 // distribution.
15 // * Neither the name of Google Inc. nor the names of its
16 // contributors may be used to endorse or promote products derived from
17 // this software without specific prior written permission.
18 //
19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31 // Author: kenton@google.com (Kenton Varda)
32 // Based on original Protocol Buffers design by
33 // Sanjay Ghemawat, Jeff Dean, and others.
34
35 #include <algorithm>
36
37 #include <google/protobuf/repeated_field.h>
38 #include <google/protobuf/stubs/logging.h>
39 #include <google/protobuf/stubs/common.h>
40
41 namespace google {
42 namespace protobuf {
43
44 namespace internal {
45
InternalExtend(int extend_amount)46 void** RepeatedPtrFieldBase::InternalExtend(int extend_amount) {
47 int new_size = current_size_ + extend_amount;
48 if (total_size_ >= new_size) {
49 // N.B.: rep_ is non-NULL because extend_amount is always > 0, hence
50 // total_size must be non-zero since it is lower-bounded by new_size.
51 return &rep_->elements[current_size_];
52 }
53 Rep* old_rep = rep_;
54 Arena* arena = GetArenaNoVirtual();
55 new_size = std::max(kMinRepeatedFieldAllocationSize,
56 std::max(total_size_ * 2, new_size));
57 GOOGLE_CHECK_LE(new_size,
58 (std::numeric_limits<size_t>::max() - kRepHeaderSize) /
59 sizeof(old_rep->elements[0]))
60 << "Requested size is too large to fit into size_t.";
61 if (arena == NULL) {
62 rep_ = reinterpret_cast<Rep*>(
63 new char[kRepHeaderSize + sizeof(old_rep->elements[0]) * new_size]);
64 } else {
65 rep_ = reinterpret_cast<Rep*>(
66 ::google::protobuf::Arena::CreateArray<char>(arena,
67 kRepHeaderSize + sizeof(old_rep->elements[0]) * new_size));
68 }
69 total_size_ = new_size;
70 if (old_rep && old_rep->allocated_size > 0) {
71 memcpy(rep_->elements, old_rep->elements,
72 old_rep->allocated_size * sizeof(rep_->elements[0]));
73 rep_->allocated_size = old_rep->allocated_size;
74 } else {
75 rep_->allocated_size = 0;
76 }
77 if (arena == NULL) {
78 delete [] reinterpret_cast<char*>(old_rep);
79 }
80 return &rep_->elements[current_size_];
81 }
82
Reserve(int new_size)83 void RepeatedPtrFieldBase::Reserve(int new_size) {
84 if (new_size > current_size_) {
85 InternalExtend(new_size - current_size_);
86 }
87 }
88
CloseGap(int start,int num)89 void RepeatedPtrFieldBase::CloseGap(int start, int num) {
90 if (rep_ == NULL) return;
91 // Close up a gap of "num" elements starting at offset "start".
92 for (int i = start + num; i < rep_->allocated_size; ++i)
93 rep_->elements[i - num] = rep_->elements[i];
94 current_size_ -= num;
95 rep_->allocated_size -= num;
96 }
97
98 } // namespace internal
99
100
101 } // namespace protobuf
102 } // namespace google
103