ceph/src/seastar/include/seastar/core/print.hh

   1 /*
   2  * This file is open source software, licensed to you under the terms
   3  * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
   4  * distributed with this work for additional information regarding copyright
   5  * ownership.  You may not use this file except in compliance with the License.
   6  *
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing,
  12  * software distributed under the License is distributed on an
  13  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  14  * KIND, either express or implied.  See the License for the
  15  * specific language governing permissions and limitations
  16  * under the License.
  17  */
  18 /*
  19  * Copyright (C) 2014 Cloudius Systems, Ltd.
  20  */
  21
  22 #pragma once
  23
  24 #include <fmt/ostream.h>
  25 #include <fmt/printf.h>
  26 #include <iostream>
  27 #include <iomanip>
  28 #include <chrono>
  29 #include <sstream>
  30 #include <seastar/core/sstring.hh>
  31
  32 #if 0
  33 inline
  34 std::ostream&
  35 operator<<(std::ostream& os, const void* ptr) {
  36     auto flags = os.flags();
  37     os << "0x" << std::hex << reinterpret_cast<uintptr_t>(ptr);
  38     os.flags(flags);
  39     return os;
  40 }
  41 #endif
  42
  43 inline
  44 std::ostream&
  45 operator<<(std::ostream&& os, const void* ptr) {
  46     return os << ptr; // selects non-rvalue version
  47 }
  48
  49 namespace seastar {
  50
  51 template <typename... A>
  52 std::ostream&
  53 fprint(std::ostream& os, const char* fmt, A&&... a) {
  54     ::fmt::fprintf(os, fmt, std::forward<A>(a)...);
  55     return os;
  56 }
  57
  58 template <typename... A>
  59 void
  60 print(const char* fmt, A&&... a) {
  61     ::fmt::printf(fmt, std::forward<A>(a)...);
  62 }
  63
  64 template <typename... A>
  65 std::string
  66 sprint(const char* fmt, A&&... a) {
  67     std::ostringstream os;
  68     ::fmt::fprintf(os, fmt, std::forward<A>(a)...);
  69     return os.str();
  70 }
  71
  72 template <typename... A>
  73 std::string
  74 sprint(const sstring& fmt, A&&... a) {
  75     std::ostringstream os;
  76     ::fmt::fprintf(os, fmt.c_str(), std::forward<A>(a)...);
  77     return os.str();
  78 }
  79
  80 template <typename Iterator>
  81 std::string
  82 format_separated(Iterator b, Iterator e, const char* sep = ", ") {
  83     std::string ret;
  84     if (b == e) {
  85         return ret;
  86     }
  87     ret += *b++;
  88     while (b != e) {
  89         ret += sep;
  90         ret += *b++;
  91     }
  92     return ret;
  93 }
  94
  95 template <typename TimePoint>
  96 struct usecfmt_wrapper {
  97     TimePoint val;
  98 };
  99
 100 template <typename TimePoint>
 101 inline
 102 usecfmt_wrapper<TimePoint>
 103 usecfmt(TimePoint tp) {
 104     return { tp };
 105 };
 106
 107 template <typename Clock, typename Rep, typename Period>
 108 std::ostream&
 109 operator<<(std::ostream& os, usecfmt_wrapper<std::chrono::time_point<Clock, std::chrono::duration<Rep, Period>>> tp) {
 110     auto usec = std::chrono::duration_cast<std::chrono::microseconds>(tp.val.time_since_epoch()).count();
 111     std::ostream tmp(os.rdbuf());
 112     tmp << std::setw(12) << (usec / 1000000) << "." << std::setw(6) << std::setfill('0') << (usec % 1000000);
 113     return os;
 114 }
 115
 116 template <typename... A>
 117 void
 118 log(A&&... a) {
 119     std::cout << usecfmt(std::chrono::high_resolution_clock::now()) << " ";
 120     print(std::forward<A>(a)...);
 121 }
 122
 123 /**
 124  * Evaluate the formatted string in a native fmt library format
 125  *
 126  * @param fmt format string with the native fmt library syntax
 127  * @param a positional parameters
 128  *
 129  * @return sstring object with the result of applying the given positional
 130  *         parameters on a given format string.
 131  */
 132 template <typename... A>
 133 sstring
 134 format(const char* fmt, A&&... a) {
 135     fmt::memory_buffer out;
 136     fmt::format_to(out, fmt, std::forward<A>(a)...);
 137     return sstring{out.data(), out.size()};
 138 }
 139
 140 // temporary, use fmt::print() instead
 141 template <typename... A>
 142 std::ostream&
 143 fmt_print(std::ostream& os, const char* format, A&&... a) {
 144     fmt::print(os, format, std::forward<A>(a)...);
 145     return os;
 146 }
 147
 148 }