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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
// 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.
#pragma once
// This provides the pw::string::Format functions, which are safer alternatives
// to std::snprintf and std::vsnprintf. The snprintf return value is awkward to
// interpret, and misinterpreting it can lead to serious bugs.
// These functions return a StatusWithSize. The Status is set to reflect any
// errors and the return value is always the number of characters written before
// the null terminator.
#include <cstdarg>
#include "pw_preprocessor/compiler.h"
#include "pw_span/span.h"
#include "pw_status/status_with_size.h"
namespace pw::string {
// Writes a printf-style formatted string to the provided buffer, similarly to
// std::snprintf. Returns the number of characters written, excluding the null
// terminator. The buffer is always null-terminated unless it is empty.
// The status is
// Status::OK if the operation succeeded,
// Status::RESOURCE_EXHAUSTED if the buffer was too small to fit the output,
// Status::INVALID_ARGUMENT if there was a formatting error.
StatusWithSize Format(const span<char>& buffer, const char* format, ...);
// Writes a printf-style formatted string with va_list-packed arguments to the
// provided buffer, similarly to std::vsnprintf. The return value is the same as
// above.
StatusWithSize FormatVaList(const span<char>& buffer,
const char* format,
va_list args);
} // namespace pw::string