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Diffstat (limited to 'include/fmt/os.h')
| -rw-r--r-- | include/fmt/os.h | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/include/fmt/os.h b/include/fmt/os.h new file mode 100644 index 00000000..d44ea0c9 --- /dev/null +++ b/include/fmt/os.h @@ -0,0 +1,480 @@ +// Formatting library for C++ - optional OS-specific functionality +// +// Copyright (c) 2012 - present, Victor Zverovich +// All rights reserved. +// +// For the license information refer to format.h. + +#ifndef FMT_OS_H_ +#define FMT_OS_H_ + +#if defined(__MINGW32__) || defined(__CYGWIN__) +// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/. +# undef __STRICT_ANSI__ +#endif + +#include <cerrno> +#include <clocale> // for locale_t +#include <cstddef> +#include <cstdio> +#include <cstdlib> // for strtod_l + +#if defined __APPLE__ || defined(__FreeBSD__) +# include <xlocale.h> // for LC_NUMERIC_MASK on OS X +#endif + +#include "format.h" + +// UWP doesn't provide _pipe. +#if FMT_HAS_INCLUDE("winapifamily.h") +# include <winapifamily.h> +#endif +#if (FMT_HAS_INCLUDE(<fcntl.h>) || defined(__APPLE__) || \ + defined(__linux__)) && \ + (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP)) +# include <fcntl.h> // for O_RDONLY +# define FMT_USE_FCNTL 1 +#else +# define FMT_USE_FCNTL 0 +#endif + +#ifndef FMT_POSIX +# if defined(_WIN32) && !defined(__MINGW32__) +// Fix warnings about deprecated symbols. +# define FMT_POSIX(call) _##call +# else +# define FMT_POSIX(call) call +# endif +#endif + +// Calls to system functions are wrapped in FMT_SYSTEM for testability. +#ifdef FMT_SYSTEM +# define FMT_POSIX_CALL(call) FMT_SYSTEM(call) +#else +# define FMT_SYSTEM(call) ::call +# ifdef _WIN32 +// Fix warnings about deprecated symbols. +# define FMT_POSIX_CALL(call) ::_##call +# else +# define FMT_POSIX_CALL(call) ::call +# endif +#endif + +// Retries the expression while it evaluates to error_result and errno +// equals to EINTR. +#ifndef _WIN32 +# define FMT_RETRY_VAL(result, expression, error_result) \ + do { \ + (result) = (expression); \ + } while ((result) == (error_result) && errno == EINTR) +#else +# define FMT_RETRY_VAL(result, expression, error_result) result = (expression) +#endif + +#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1) + +FMT_BEGIN_NAMESPACE + +/** + \rst + A reference to a null-terminated string. It can be constructed from a C + string or ``std::string``. + + You can use one of the following type aliases for common character types: + + +---------------+-----------------------------+ + | Type | Definition | + +===============+=============================+ + | cstring_view | basic_cstring_view<char> | + +---------------+-----------------------------+ + | wcstring_view | basic_cstring_view<wchar_t> | + +---------------+-----------------------------+ + + This class is most useful as a parameter type to allow passing + different types of strings to a function, for example:: + + template <typename... Args> + std::string format(cstring_view format_str, const Args & ... args); + + format("{}", 42); + format(std::string("{}"), 42); + \endrst + */ +template <typename Char> class basic_cstring_view { + private: + const Char* data_; + + public: + /** Constructs a string reference object from a C string. */ + basic_cstring_view(const Char* s) : data_(s) {} + + /** + \rst + Constructs a string reference from an ``std::string`` object. + \endrst + */ + basic_cstring_view(const std::basic_string<Char>& s) : data_(s.c_str()) {} + + /** Returns the pointer to a C string. */ + const Char* c_str() const { return data_; } +}; + +using cstring_view = basic_cstring_view<char>; +using wcstring_view = basic_cstring_view<wchar_t>; + +// An error code. +class error_code { + private: + int value_; + + public: + explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {} + + int get() const FMT_NOEXCEPT { return value_; } +}; + +#ifdef _WIN32 +namespace detail { +// A converter from UTF-16 to UTF-8. +// It is only provided for Windows since other systems support UTF-8 natively. +class utf16_to_utf8 { + private: + memory_buffer buffer_; + + public: + utf16_to_utf8() {} + FMT_API explicit utf16_to_utf8(wstring_view s); + operator string_view() const { return string_view(&buffer_[0], size()); } + size_t size() const { return buffer_.size() - 1; } + const char* c_str() const { return &buffer_[0]; } + std::string str() const { return std::string(&buffer_[0], size()); } + + // Performs conversion returning a system error code instead of + // throwing exception on conversion error. This method may still throw + // in case of memory allocation error. + FMT_API int convert(wstring_view s); +}; + +FMT_API void format_windows_error(buffer<char>& out, int error_code, + string_view message) FMT_NOEXCEPT; +} // namespace detail + +/** A Windows error. */ +class windows_error : public system_error { + private: + FMT_API void init(int error_code, string_view format_str, format_args args); + + public: + /** + \rst + Constructs a :class:`fmt::windows_error` object with the description + of the form + + .. parsed-literal:: + *<message>*: *<system-message>* + + where *<message>* is the formatted message and *<system-message>* is the + system message corresponding to the error code. + *error_code* is a Windows error code as given by ``GetLastError``. + If *error_code* is not a valid error code such as -1, the system message + will look like "error -1". + + **Example**:: + + // This throws a windows_error with the description + // cannot open file 'madeup': The system cannot find the file specified. + // or similar (system message may vary). + const char *filename = "madeup"; + LPOFSTRUCT of = LPOFSTRUCT(); + HFILE file = OpenFile(filename, &of, OF_READ); + if (file == HFILE_ERROR) { + throw fmt::windows_error(GetLastError(), + "cannot open file '{}'", filename); + } + \endrst + */ + template <typename... Args> + windows_error(int error_code, string_view message, const Args&... args) { + init(error_code, message, make_format_args(args...)); + } +}; + +// Reports a Windows error without throwing an exception. +// Can be used to report errors from destructors. +FMT_API void report_windows_error(int error_code, + string_view message) FMT_NOEXCEPT; +#endif // _WIN32 + +// A buffered file. +class buffered_file { + private: + FILE* file_; + + friend class file; + + explicit buffered_file(FILE* f) : file_(f) {} + + public: + buffered_file(const buffered_file&) = delete; + void operator=(const buffered_file&) = delete; + + // Constructs a buffered_file object which doesn't represent any file. + buffered_file() FMT_NOEXCEPT : file_(nullptr) {} + + // Destroys the object closing the file it represents if any. + FMT_API ~buffered_file() FMT_NOEXCEPT; + + public: + buffered_file(buffered_file&& other) FMT_NOEXCEPT : file_(other.file_) { + other.file_ = nullptr; + } + + buffered_file& operator=(buffered_file&& other) { + close(); + file_ = other.file_; + other.file_ = nullptr; + return *this; + } + + // Opens a file. + FMT_API buffered_file(cstring_view filename, cstring_view mode); + + // Closes the file. + FMT_API void close(); + + // Returns the pointer to a FILE object representing this file. + FILE* get() const FMT_NOEXCEPT { return file_; } + + // We place parentheses around fileno to workaround a bug in some versions + // of MinGW that define fileno as a macro. + FMT_API int(fileno)() const; + + void vprint(string_view format_str, format_args args) { + fmt::vprint(file_, format_str, args); + } + + template <typename... Args> + inline void print(string_view format_str, const Args&... args) { + vprint(format_str, make_format_args(args...)); + } +}; + +#if FMT_USE_FCNTL +// A file. Closed file is represented by a file object with descriptor -1. +// Methods that are not declared with FMT_NOEXCEPT may throw +// fmt::system_error in case of failure. Note that some errors such as +// closing the file multiple times will cause a crash on Windows rather +// than an exception. You can get standard behavior by overriding the +// invalid parameter handler with _set_invalid_parameter_handler. +class file { + private: + int fd_; // File descriptor. + + // Constructs a file object with a given descriptor. + explicit file(int fd) : fd_(fd) {} + + public: + // Possible values for the oflag argument to the constructor. + enum { + RDONLY = FMT_POSIX(O_RDONLY), // Open for reading only. + WRONLY = FMT_POSIX(O_WRONLY), // Open for writing only. + RDWR = FMT_POSIX(O_RDWR), // Open for reading and writing. + CREATE = FMT_POSIX(O_CREAT), // Create if the file doesn't exist. + APPEND = FMT_POSIX(O_APPEND) // Open in append mode. + }; + + // Constructs a file object which doesn't represent any file. + file() FMT_NOEXCEPT : fd_(-1) {} + + // Opens a file and constructs a file object representing this file. + FMT_API file(cstring_view path, int oflag); + + public: + file(const file&) = delete; + void operator=(const file&) = delete; + + file(file&& other) FMT_NOEXCEPT : fd_(other.fd_) { other.fd_ = -1; } + + file& operator=(file&& other) FMT_NOEXCEPT { + close(); + fd_ = other.fd_; + other.fd_ = -1; + return *this; + } + + // Destroys the object closing the file it represents if any. + FMT_API ~file() FMT_NOEXCEPT; + + // Returns the file descriptor. + int descriptor() const FMT_NOEXCEPT { return fd_; } + + // Closes the file. + FMT_API void close(); + + // Returns the file size. The size has signed type for consistency with + // stat::st_size. + FMT_API long long size() const; + + // Attempts to read count bytes from the file into the specified buffer. + FMT_API size_t read(void* buffer, size_t count); + + // Attempts to write count bytes from the specified buffer to the file. + FMT_API size_t write(const void* buffer, size_t count); + + // Duplicates a file descriptor with the dup function and returns + // the duplicate as a file object. + FMT_API static file dup(int fd); + + // Makes fd be the copy of this file descriptor, closing fd first if + // necessary. + FMT_API void dup2(int fd); + + // Makes fd be the copy of this file descriptor, closing fd first if + // necessary. + FMT_API void dup2(int fd, error_code& ec) FMT_NOEXCEPT; + + // Creates a pipe setting up read_end and write_end file objects for reading + // and writing respectively. + FMT_API static void pipe(file& read_end, file& write_end); + + // Creates a buffered_file object associated with this file and detaches + // this file object from the file. + FMT_API buffered_file fdopen(const char* mode); +}; + +// Returns the memory page size. +long getpagesize(); + +namespace detail { + +struct buffer_size { + size_t value = 0; + buffer_size operator=(size_t val) const { + auto bs = buffer_size(); + bs.value = val; + return bs; + } +}; + +struct ostream_params { + int oflag = file::WRONLY | file::CREATE; + size_t buffer_size = BUFSIZ > 32768 ? BUFSIZ : 32768; + + ostream_params() {} + + template <typename... T> + ostream_params(T... params, int oflag) : ostream_params(params...) { + this->oflag = oflag; + } + + template <typename... T> + ostream_params(T... params, detail::buffer_size bs) + : ostream_params(params...) { + this->buffer_size = bs.value; + } +}; +} // namespace detail + +static constexpr detail::buffer_size buffer_size; + +// A fast output stream which is not thread-safe. +class ostream final : private detail::buffer<char> { + private: + file file_; + + void flush() { + if (size() == 0) return; + file_.write(data(), size()); + clear(); + } + + FMT_API void grow(size_t) override final; + + ostream(cstring_view path, const detail::ostream_params& params) + : file_(path, params.oflag) { + set(new char[params.buffer_size], params.buffer_size); + } + + public: + ostream(ostream&& other) + : detail::buffer<char>(other.data(), other.size(), other.capacity()), + file_(std::move(other.file_)) { + other.set(nullptr, 0); + } + ~ostream() { + flush(); + delete[] data(); + } + + template <typename... T> + friend ostream output_file(cstring_view path, T... params); + + void close() { + flush(); + file_.close(); + } + + template <typename S, typename... Args> + void print(const S& format_str, const Args&... args) { + format_to(detail::buffer_appender<char>(*this), format_str, args...); + } +}; + +/** + Opens a file for writing. Supported parameters passed in `params`: + * ``<integer>``: Output flags (``file::WRONLY | file::CREATE`` by default) + * ``buffer_size=<integer>``: Output buffer size + */ +template <typename... T> +inline ostream output_file(cstring_view path, T... params) { + return {path, detail::ostream_params(params...)}; +} +#endif // FMT_USE_FCNTL + +#ifdef FMT_LOCALE +// A "C" numeric locale. +class locale { + private: +# ifdef _WIN32 + using locale_t = _locale_t; + + static void freelocale(locale_t loc) { _free_locale(loc); } + + static double strtod_l(const char* nptr, char** endptr, _locale_t loc) { + return _strtod_l(nptr, endptr, loc); + } +# endif + + locale_t locale_; + + public: + using type = locale_t; + locale(const locale&) = delete; + void operator=(const locale&) = delete; + + locale() { +# ifndef _WIN32 + locale_ = FMT_SYSTEM(newlocale(LC_NUMERIC_MASK, "C", nullptr)); +# else + locale_ = _create_locale(LC_NUMERIC, "C"); +# endif + if (!locale_) FMT_THROW(system_error(errno, "cannot create locale")); + } + ~locale() { freelocale(locale_); } + + type get() const { return locale_; } + + // Converts string to floating-point number and advances str past the end + // of the parsed input. + double strtod(const char*& str) const { + char* end = nullptr; + double result = strtod_l(str, &end, locale_); + str = end; + return result; + } +}; +using Locale FMT_DEPRECATED_ALIAS = locale; +#endif // FMT_LOCALE +FMT_END_NAMESPACE + +#endif // FMT_OS_H_ |