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 of
5 // 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 under
13 // 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
clear()24 void StringBuilder::clear() {
25 *size_ = 0;
26 NullTerminate();
27 status_ = StatusCode(OkStatus());
28 last_status_ = StatusCode(OkStatus());
29 }
30
append(size_t count,char ch)31 StringBuilder& StringBuilder::append(size_t count, char ch) {
32 char* const append_destination = buffer_.data() + size();
33 std::fill_n(append_destination, ResizeAndTerminate(count), ch);
34 return *this;
35 }
36
append(const char * str,size_t count)37 StringBuilder& StringBuilder::append(const char* str, size_t count) {
38 char* const append_destination = buffer_.data() + size();
39 std::copy_n(str, ResizeAndTerminate(count), append_destination);
40 return *this;
41 }
42
append(const char * str)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(string::ClampedCString(str, buffer_.size() - size()));
48 }
49
append(std::string_view str)50 StringBuilder& StringBuilder::append(std::string_view str) {
51 return append(str.data(), str.size());
52 }
53
append(std::string_view str,size_t pos,size_t count)54 StringBuilder& StringBuilder::append(std::string_view str,
55 size_t pos,
56 size_t count) {
57 if (pos > str.size()) {
58 SetErrorStatus(Status::OutOfRange());
59 return *this;
60 }
61
62 return append(str.data() + pos, std::min(str.size() - pos, count));
63 }
64
ResizeAndTerminate(size_t chars_to_append)65 size_t StringBuilder::ResizeAndTerminate(size_t chars_to_append) {
66 const size_t copied = std::min(chars_to_append, max_size() - size());
67 // NOTE: `+=` is not used in order to avoid implicit integer conversion which
68 // results in an error on some compilers.
69 *size_ = static_cast<InlineString<>::size_type>(copied + *size_);
70 NullTerminate();
71
72 if (buffer_.empty() || chars_to_append != copied) {
73 SetErrorStatus(Status::ResourceExhausted());
74 } else {
75 last_status_ = StatusCode(OkStatus());
76 }
77 return copied;
78 }
79
resize(size_t new_size)80 void StringBuilder::resize(size_t new_size) {
81 if (new_size <= size()) {
82 *size_ = static_cast<InlineString<>::size_type>(new_size);
83 NullTerminate();
84 last_status_ = StatusCode(OkStatus());
85 } else {
86 SetErrorStatus(Status::OutOfRange());
87 }
88 }
89
Format(const char * format,...)90 StringBuilder& StringBuilder::Format(const char* format, ...) {
91 va_list args;
92 va_start(args, format);
93 FormatVaList(format, args);
94 va_end(args);
95
96 return *this;
97 }
98
FormatVaList(const char * format,va_list args)99 StringBuilder& StringBuilder::FormatVaList(const char* format, va_list args) {
100 HandleStatusWithSize(
101 string::FormatVaList(buffer_.subspan(size()), format, args));
102 return *this;
103 }
104
WriteBytes(span<const std::byte> data)105 void StringBuilder::WriteBytes(span<const std::byte> data) {
106 if (size() + data.size() * 2 > max_size()) {
107 SetErrorStatus(Status::ResourceExhausted());
108 } else {
109 for (std::byte val : data) {
110 *this << val;
111 }
112 }
113 }
114
CopySizeAndStatus(const StringBuilder & other)115 void StringBuilder::CopySizeAndStatus(const StringBuilder& other) {
116 *size_ = static_cast<InlineString<>::size_type>(other.size());
117 status_ = other.status_;
118 last_status_ = other.last_status_;
119 }
120
HandleStatusWithSize(StatusWithSize written)121 void StringBuilder::HandleStatusWithSize(StatusWithSize written) {
122 const Status status = written.status();
123 last_status_ = StatusCode(status);
124 if (!status.ok()) {
125 status_ = StatusCode(status);
126 }
127
128 // NOTE: `+=` is not used in order to avoid implicit integer conversion which
129 // results in an error on some compilers.
130 *size_ = static_cast<InlineString<>::size_type>(written.size() + *size_);
131 }
132
SetErrorStatus(Status status)133 void StringBuilder::SetErrorStatus(Status status) {
134 last_status_ = StatusCode(status);
135 status_ = StatusCode(status);
136 }
137
138 } // namespace pw
139