1 /*
2  * Copyright 2023 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "log.h"
18 
19 #include <fmt/color.h>
20 #include <fmt/core.h>
21 
22 #include <array>
23 #include <chrono>
24 #include <cstdio>
25 #include <cstdlib>
26 #include <cstring>
27 #include <ctime>
28 #include <optional>
29 
30 namespace rootcanal::log {
31 
32 // Enable flag for log styling.
33 static bool enable_log_color = true;
34 
SetLogColorEnable(bool enable)35 void SetLogColorEnable(bool enable) { enable_log_color = enable; }
36 
37 static std::array<char, 5> verbosity_tag = {'D', 'I', 'W', 'E', 'F'};
38 
39 static std::array<fmt::text_style, 5> text_style = {
40     fmt::fg(fmt::color::dim_gray),
41     fmt::fg(fmt::color::floral_white),
42     fmt::emphasis::bold | fmt::fg(fmt::color::yellow),
43     fmt::emphasis::bold | fmt::fg(fmt::color::orange_red),
44     fmt::emphasis::bold | fmt::fg(fmt::color::red),
45 };
46 
47 static std::array<fmt::color, 16> text_color = {
48     fmt::color::cadet_blue,   fmt::color::aquamarine,
49     fmt::color::indian_red,   fmt::color::blue_violet,
50     fmt::color::chartreuse,   fmt::color::medium_sea_green,
51     fmt::color::deep_pink,    fmt::color::medium_orchid,
52     fmt::color::green_yellow, fmt::color::dark_orange,
53     fmt::color::golden_rod,   fmt::color::medium_slate_blue,
54     fmt::color::coral,        fmt::color::lemon_chiffon,
55     fmt::color::wheat,        fmt::color::turquoise,
56 };
57 
VLog(Verbosity verb,char const * file,int line,std::optional<int> instance,char const * format,fmt::format_args args)58 void VLog(Verbosity verb, char const* file, int line,
59           std::optional<int> instance, char const* format,
60           fmt::format_args args) {
61   // Generate the time label.
62   auto now = std::chrono::system_clock::now();
63   auto now_ms = std::chrono::time_point_cast<std::chrono::milliseconds>(now);
64   auto now_t = std::chrono::system_clock::to_time_t(now);
65   char time_str[19];  // "mm-dd_HH:MM:SS.mmm\0" is 19 byte long
66   auto n = std::strftime(time_str, sizeof(time_str), "%m-%d %H:%M:%S",
67                          std::localtime(&now_t));
68   snprintf(time_str + n, sizeof(time_str) - n, ".%03u",
69            static_cast<unsigned int>(now_ms.time_since_epoch().count() % 1000));
70 
71   // Generate the file label.
72   char delimiter = '/';
73   char const* file_name = ::strrchr(file, delimiter);
74   file_name = file_name == nullptr ? file : file_name + 1;
75   char file_str[40];  // file:line limited to 40 characters
76   snprintf(file_str, sizeof(file_str), "%.35s:%d", file_name, line);
77 
78   fmt::print("root-canal {} {} {:<35.35} ", verbosity_tag[verb], time_str,
79              file_str);
80 
81   if (instance.has_value() && enable_log_color) {
82     fmt::color instance_color = text_color[*instance % text_color.size()];
83     fmt::print(fmt::bg(instance_color) | fmt::fg(fmt::color::black), " {:>2} ",
84                *instance);
85     fmt::print(" ");
86   } else if (instance.has_value()) {
87     fmt::print(" {:>2}  ", *instance);
88   } else {
89     fmt::print("     ");
90   }
91 
92   if (enable_log_color) {
93     fmt::text_style style = text_style[verb];
94     fmt::vprint(stdout, style, format, args);
95   } else {
96     fmt::vprint(stdout, format, args);
97   }
98 
99   fmt::print("\n");
100 
101   if (verb == Verbosity::kFatal) {
102     std::abort();
103   }
104 }
105 
106 }  // namespace rootcanal::log
107