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// Copyright 2019 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
// This size report uses pw::string::Format and std::snprintf to write to the
// same buffer numerous times. No error handling or size checking is done.
//
// This compares the overhead of calling pw::string::Format with a span to
// calling std::snprintf with a separate pointer and buffer size.
#ifndef USE_FORMAT
#error "USE_FORMAT must be defined"
#endif // USE_FORMAT
#if USE_FORMAT
#include "pw_string/format.h"
#define FORMAT_CASE(...) \
pw::string::Format(buffer, __VA_ARGS__) \
.IgnoreError() // TODO(b/242598609): Handle Status properly
#else // std::snprintf
#include <cstdio>
#define FORMAT_CASE(...) std::snprintf(buffer, buffer_size, __VA_ARGS__)
#endif // USE_FORMAT
namespace pw::string {
char buffer_1[128];
char buffer_2[128];
char* volatile get_buffer_1 = buffer_1;
char* volatile get_buffer_2 = buffer_2;
volatile unsigned get_size;
void OutputStringsToBuffer() {
#if USE_FORMAT
auto buffer = span(get_buffer_1, get_size);
#else
char* buffer = get_buffer_1;
unsigned buffer_size = get_size;
#endif // USE_FORMAT
const char* string = get_buffer_2;
unsigned value = get_size;
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
FORMAT_CASE("The quick brown");
FORMAT_CASE("%s", string);
FORMAT_CASE("jumped over the %s d%ug.", string, value);
FORMAT_CASE("One two %s %d %s", "three", 4, "five");
FORMAT_CASE("a %c %x d %s %f g", 'b', 0xc, "e", 0.0f);
}
} // namespace pw::string
int main() {
pw::string::OutputStringsToBuffer();
return 0;
}
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