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#ifndef NEWSBEUTER_STRPRINTF_H_
#define NEWSBEUTER_STRPRINTF_H_
#include <memory>
#include <string>
namespace newsbeuter {
class strprintf {
public:
static std::pair<std::string, std::string>
split_format(const std::string& printf_format);
static std::string fmt(const std::string& format) {
char buffer[1024];
std::string result;
// Empty string is a dummy value that we pass in order to silence
// Clang's warning about format not being a literal.
//
// The thing is, at this point we know *for sure* that the format
// either contains no formats at all, or only escaped percent signs
// (which don't require any additional arguments to snprintf). It's
// just the way fmt recurses. The only reason we're calling
// snprintf at all is to process these escaped percent signs, if
// any. So we don't need additional parameters.
unsigned int len = 1 + snprintf(
buffer, sizeof(buffer), format.c_str(), "");
if (len <= sizeof(buffer)) {
result = buffer;
} else {
std::unique_ptr<char> buf(new char[len]);
snprintf(buf.get(), len, format.c_str(), "");
result = buf.get();
}
return result;
}
template<typename... Args>
static std::string fmt(
const std::string& format, const std::string& argument, Args... args)
{
return fmt(format, argument.c_str(), args...);
}
template<typename T, typename... Args>
static std::string fmt(
const std::string& format, const T& argument, Args... args)
{
std::string local_format, remaining_format;
std::tie(local_format, remaining_format) = split_format(format);
char buffer[1024];
std::string result;
unsigned int len = 1 + snprintf(
buffer, sizeof(buffer), local_format.c_str(), argument);
if (len <= sizeof(buffer)) {
result = buffer;
} else {
std::unique_ptr<char> buf(new char[len]);
snprintf(buf.get(), len, local_format.c_str(), argument);
result = buf.get();
}
return result + fmt(remaining_format, args...);
}
};
}
#endif /* NEWSBEUTER_STRPRINTF_H_ */
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