Wyatt Hepler | ce9b952 | 2019-11-11 10:45:48 -0800 | [diff] [blame^] | 1 | // Copyright 2019 The Pigweed Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| 4 | // use this file except in compliance with the License. You may obtain a copy |
| 5 | // of the License at |
| 6 | // |
| 7 | // https://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| 11 | // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 12 | // License for the specific language governing permissions and limitations |
| 13 | // under the License. |
| 14 | |
| 15 | #include "pw_string/string_builder.h" |
| 16 | |
| 17 | #include <cstdio> |
| 18 | |
| 19 | #include "pw_string/format.h" |
| 20 | #include "pw_string/util.h" |
| 21 | |
| 22 | namespace pw { |
| 23 | |
| 24 | void StringBuilder::clear() { |
| 25 | size_ = 0; |
| 26 | NullTerminate(); |
| 27 | status_ = Status::OK; |
| 28 | last_status_ = Status::OK; |
| 29 | } |
| 30 | |
| 31 | StringBuilder& StringBuilder::append(size_t count, char ch) { |
| 32 | char* const append_destination = &buffer_[size_]; |
| 33 | std::memset(append_destination, ch, ResizeAndTerminate(count)); |
| 34 | return *this; |
| 35 | } |
| 36 | |
| 37 | StringBuilder& StringBuilder::append(const char* str, size_t count) { |
| 38 | char* const append_destination = &buffer_[size_]; |
| 39 | std::memcpy(append_destination, str, ResizeAndTerminate(count)); |
| 40 | return *this; |
| 41 | } |
| 42 | |
| 43 | StringBuilder& StringBuilder::append(const char* str) { |
| 44 | // Use buffer_.size() - size() as the maximum length so that strings too long |
| 45 | // to fit in the buffer will request one character too many, which sets the |
| 46 | // status to RESOURCE_EXHAUSTED. |
| 47 | return append(str, string::Length(str, buffer_.size() - size())); |
| 48 | } |
| 49 | |
| 50 | StringBuilder& StringBuilder::append(const std::string_view& str) { |
| 51 | return append(str.data(), str.size()); |
| 52 | } |
| 53 | |
| 54 | StringBuilder& StringBuilder::append(const std::string_view& str, |
| 55 | size_t pos, |
| 56 | size_t count) { |
| 57 | if (pos > str.size()) { |
| 58 | SetErrorStatus(Status::OUT_OF_RANGE); |
| 59 | return *this; |
| 60 | } |
| 61 | |
| 62 | return append(str.data() + pos, std::min(str.size() - pos, count)); |
| 63 | } |
| 64 | |
| 65 | size_t StringBuilder::ResizeAndTerminate(size_t chars_to_append) { |
| 66 | const size_t copied = std::min(chars_to_append, max_size() - size()); |
| 67 | size_ += copied; |
| 68 | NullTerminate(); |
| 69 | |
| 70 | if (buffer_.empty() || chars_to_append != copied) { |
| 71 | SetErrorStatus(Status::RESOURCE_EXHAUSTED); |
| 72 | } else { |
| 73 | last_status_ = Status::OK; |
| 74 | } |
| 75 | return copied; |
| 76 | } |
| 77 | |
| 78 | void StringBuilder::resize(size_t new_size) { |
| 79 | if (new_size <= size_) { |
| 80 | size_ = new_size; |
| 81 | NullTerminate(); |
| 82 | last_status_ = Status::OK; |
| 83 | } else { |
| 84 | SetErrorStatus(Status::OUT_OF_RANGE); |
| 85 | } |
| 86 | } |
| 87 | |
| 88 | StringBuilder& StringBuilder::Format(const char* format, ...) { |
| 89 | va_list args; |
| 90 | va_start(args, format); |
| 91 | Format(format, args); |
| 92 | va_end(args); |
| 93 | |
| 94 | return *this; |
| 95 | } |
| 96 | |
| 97 | StringBuilder& StringBuilder::Format(const char* format, va_list args) { |
| 98 | HandleStatusWithSize(string::Format(buffer_.subspan(size_), format, args)); |
| 99 | return *this; |
| 100 | } |
| 101 | |
| 102 | void StringBuilder::CopySizeAndStatus(const StringBuilder& other) { |
| 103 | size_ = other.size_; |
| 104 | status_ = other.status_; |
| 105 | last_status_ = other.last_status_; |
| 106 | } |
| 107 | |
| 108 | void StringBuilder::HandleStatusWithSize(StatusWithSize written) { |
| 109 | const Status status = written.status(); |
| 110 | last_status_ = status; |
| 111 | if (!status.ok()) { |
| 112 | status_ = status; |
| 113 | } |
| 114 | |
| 115 | size_ += written.size(); |
| 116 | } |
| 117 | |
| 118 | void StringBuilder::SetErrorStatus(Status status) { |
| 119 | last_status_ = status; |
| 120 | status_ = status; |
| 121 | } |
| 122 | |
| 123 | } // namespace pw |