feat: add ANSI color/style formatting

- at some log levels by defaults,
- can be used within format
This commit is contained in:
Johann Dreo 2020-10-17 22:13:40 +02:00
commit a93411c4f6
3 changed files with 266 additions and 9 deletions

View file

@ -167,6 +167,62 @@ log.depth_mark(CLUTCHLOG_DEFAULT_DEPTH_MARK); // Defaults to ">".
```
Output style
------------
The output can be colored differently depending on the log level.
```cpp
// Print error messages in bold red:
log.style(clutchlog::level::error,
clutchlog::fmt(
clutchlog::fmt::fg::red,
clutchlog::fmt::typo::bold));
```
Using the `clutchlog::fmt` class, you can style:
- the foreground color, passing a `clutchlog::fmt::fg`,
- the background color, passing a `clutchlog::fmt::bg`,
- some typographic style, passing a `clutchlog::fmt::typo`.
Any of the three arguments may be passed, in any order,
if an argument is omitted, it defaults to no color/style.
Available colors are:
- black,
- red,
- green,
- yellow,
- blue,
- magenta,
- cyan,
- white,
- none.
Available typographies:
- reset (remove any style),
- bold,
- underline,
- inverse,
- none.
You may use styling within the format message template itself, to add even more colors:
```cpp
using fmt = clutchlog::fmt;
std::ostringstream format;
fmt discreet(fmt::fg::blue);
format << "{level}: "
<< discreet("{file}:") // Used as a function (inserts a reset at the end).
<< fmt(fmt::fg::yellow) << "{line}" // Used as a tag (no reset inserted).
<< fmt(fmt::typo::reset) << " {msg}" << std::endl; // This is a reset.
log.format(format.str());
```
Note: messages at the "quiet", "error" and "warning" log levels are colored by default.
You may want to set their style to `none` if you want to cleanly insert colors in the format template.
Disabled calls
--------------
@ -229,6 +285,8 @@ the features relying on the depth of the call stack and the display of the progr
are only available for operating systems having the following headers:
`execinfo.h`, `stdlib.h` and `libgen.h` (so far, tested with Linux).
Some colors/styles may not be supported by some exotic terminal emulators.
Clutchlog needs `C++-17` with the `filesystem` feature.
You may need to indicate `-std=c++17 -lstdc++fs` to your compiler.
@ -256,3 +314,8 @@ ctest
There's a script which tests all the build types combinations: `./build_all.sh`.
How to
======

View file

@ -138,6 +138,121 @@ class clutchlog
/** }@ High-level API */
/** Formating API @{ */
/** Color and style formatter for ANSI terminal escape sequences.
*
* @note All styles may not be supported by a given terminal/operating system.
*/
class fmt {
public:
//! Foreground color codes.
enum class fg {
black = 30,
red = 31,
green = 32,
yellow = 33,
blue = 34,
magenta = 35,
cyan = 36,
white = 37,
none
} fore;
//! Background color codes.
enum class bg {
black = 40,
red = 41,
green = 42,
yellow = 43,
blue = 44,
magenta = 45,
cyan = 46,
white = 47,
none
} back;
//! Typographic style codes.
enum class typo {
reset = 0,
bold = 1,
underline = 4,
inverse = 7,
none
} style;
//! Empty constructor, only useful for a no-op formatter.
fmt() : fore(fg::none), back(bg::none), style(typo::none) { }
/** All combination of constructors with different parameters orders. @{ */
fmt( fg f, bg b = bg::none, typo s = typo::none) : fore(f), back(b), style(s) { }
fmt( fg f, typo s , bg b = bg::none) : fore(f), back(b), style(s) { }
fmt( bg b, fg f = fg::none, typo s = typo::none) : fore(f), back(b), style(s) { }
fmt( bg b, typo s , fg f = fg::none) : fore(f), back(b), style(s) { }
fmt(typo s, fg f = fg::none, bg b = bg::none) : fore(f), back(b), style(s) { }
fmt(typo s, bg b , fg f = fg::none) : fore(f), back(b), style(s) { }
/** @} */
protected:
//! Print the currently encoded format escape code on the given output stream.
std::ostream& print_on( std::ostream& os) const
{
std::vector<int> codes; codes.reserve(3);
if(this->fore != fg::none) { codes.push_back(static_cast<int>(this->fore ));}
if(this->back != bg::none) { codes.push_back(static_cast<int>(this->back ));}
if(this->style != typo::none) { codes.push_back(static_cast<int>(this->style));}
if(codes.size() == 0) {return os;}
os << "\033[";
assert(codes.size() > 0);
os << codes[0];
for(size_t i=1; i < codes.size(); ++i) {
os << ";" << codes[i];
}
os << "m";
return os;
}
public:
/** Output stream overload.
*
* Allow to use a formatter as a tag within a stream:
* @code
* clutchlog::fmt end(clutchlog::fmt::typo::reset);
* clutchlog::fmt error(clutchlog::fmt::fg::red, clutchlog::fmt::typo::bold);
* std::cout << error << "ERROR" << end << std::endl;
* @endcode
*
* @note An formatter called this way will NOT output a reset escape code.
*/
friend std::ostream& operator<<(std::ostream& os, const fmt& fmt)
{
return fmt.print_on(os);
}
/** Format the given string with the currently encoded format.
*
* Allow to use a formatter as a function:
* @code
* clutchlog::fmt error(clutchlog::fmt::fg::red, clutchlog::fmt::typo::bold);
* std::cout << error("ERROR") << std::endl;
* @endcode
*
* @note A formatter called this way WILL output a reset escape code at the end.
*/
std::string operator()( const std::string& msg ) const
{
std::ostringstream os;
this->print_on(os);
fmt end(fmt::typo::reset);
os << msg;
end.print_on(os);
return os.str();
}
}; // fmt class
/** @} Formating API */
/** Internal details @{ */
public:
@ -147,15 +262,24 @@ class clutchlog
private:
clutchlog() :
// system, main, log
_strip_calls(3),
_strip_calls(5),
_level_words({
{level::quiet,"Quiet"},
{level::error,"Error"},
{level::warning,"Warning"},
{level::quiet ,"Quiet"},
{level::error ,"Error"},
{level::warning ,"Warning"},
{level::progress,"Progress"},
{level::info,"Info"},
{level::debug,"Debug"},
{level::xdebug,"XDebug"}
{level::info ,"Info"},
{level::debug ,"Debug"},
{level::xdebug ,"XDebug"}
}),
_level_fmt({
{level::quiet ,fmt(fmt::bg::red, fmt::typo::underline)},
{level::error ,fmt(fmt::fg::red, fmt::typo::bold)},
{level::warning ,fmt(fmt::fg::magenta, fmt::typo::bold)},
{level::progress,fmt()},
{level::info ,fmt()},
{level::debug ,fmt()},
{level::xdebug ,fmt()}
}),
_format_log(CLUTCHLOG_DEFAULT_FORMAT),
_format_dump(CLUTCHDUMP_DEFAULT_FORMAT),
@ -173,6 +297,7 @@ class clutchlog
protected:
const size_t _strip_calls;
const std::map<level,std::string> _level_words;
std::map<level,fmt> _level_fmt;
std::string _format_log;
std::string _format_dump;
std::ostream* _out;
@ -202,6 +327,7 @@ class clutchlog
{}
};
//! Gather information on the current location of the call.
scope_t locate(
const level& stage,
@ -290,6 +416,9 @@ class clutchlog
line(in_line);
}
void style(level stage, fmt style) { _level_fmt.at(stage) = style; }
fmt style(level stage) const { return _level_fmt.at(stage); }
/** }@ Configuration */
public:
@ -389,9 +518,9 @@ class clutchlog
format = replace(format, "\\{msg\\}", what);
format = replace(format, "\\{file\\}", file);
format = replace(format, "\\{func\\}", func);
format = replace(format, "\\{level\\}", _level_words.at(stage));
format = replace(format, "\\{line\\}", line);
format = replace(format, "\\{level\\}", _level_words.at(stage));
std::string letter(1, _level_words.at(stage).at(0)); // char -> string
format = replace(format, "\\{level_letter\\}", letter);
@ -406,7 +535,7 @@ class clutchlog
format = replace(format, "\\{depth_marks\\}", chevrons.str());
#endif
return format;
return _level_fmt.at(stage)(format);
}
void log(
@ -498,6 +627,24 @@ class clutchlog
public:
static clutchlog& logger() { }
enum level {quiet=0, error=1, warning=2, progress=3, info=4, debug=5, xdebug=6};
class fmt {
public:
enum class fg { black, red, green, yellow, blue, magenta, cyan, white, none } fore;
enum class bg { black, red, green, yellow, blue, magenta, cyan, white, none } back;
enum class typo { reset, bold, underline, inverse, none } style;
fmt() : fore(fg::none), back(bg::none), style(typo::none) { }
fmt( fg f, bg b = bg::none, typo s = typo::none) : fore(f), back(b), style(s) { }
fmt( fg f, typo s , bg b = bg::none) : fore(f), back(b), style(s) { }
fmt( bg b, fg f = fg::none, typo s = typo::none) : fore(f), back(b), style(s) { }
fmt( bg b, typo s , fg f = fg::none) : fore(f), back(b), style(s) { }
fmt(typo s, fg f = fg::none, bg b = bg::none) : fore(f), back(b), style(s) { }
fmt(typo s, bg b , fg f = fg::none) : fore(f), back(b), style(s) { }
protected:
std::ostream& print_on(std::ostream&) const { }
public:
friend std::ostream& operator<<(std::ostream&, const fmt&) { }
std::string operator()(const std::string&) const { }
};
public:
clutchlog(clutchlog const&) = delete;
void operator=(clutchlog const&) = delete;
@ -546,6 +693,8 @@ class clutchlog
)
{ }
#pragma GCC diagnostic pop
void style(level, fmt) { }
fmt style(level) const { }
public:
std::string replace(
const std::string&,

45
tests/t-color.cpp Normal file
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@ -0,0 +1,45 @@
#include <iostream>
#include <limits>
#include "../clutchlog/clutchlog.h"
int main(/*const int argc, char* argv[]*/)
{
using typo = clutchlog::fmt::typo;
using fg = clutchlog::fmt::fg;
using bg = clutchlog::fmt::bg;
clutchlog::fmt none;
clutchlog::fmt end(typo::reset);
clutchlog::fmt note(typo::bold);
clutchlog::fmt info(fg::green);
clutchlog::fmt warning(fg::magenta, typo::bold);
clutchlog::fmt error(fg::red, typo::bold);
clutchlog::fmt critical(bg::red, typo::underline, fg::black);
auto& log = clutchlog::logger();
log.threshold(clutchlog::level::info);
// Change a style.
log.style(clutchlog::level::quiet, error);
CLUTCHLOG(quiet,"Styles demo");
CLUTCHLOG(info,"Either using functions...");
std::cout << none("No style: ") << std::endl;
std::cout << note("NOTE: bold") << std::endl;
std::cout << info("INFO: green") << std::endl;
CLUTCHLOG(info,"... or tags.");
std::cout << warning << "WARNING" << end << ": bold magenta" << std::endl;
std::cout << error << "ERROR" << end << ": bold red" << std::endl;
std::cout << critical << "CRITICAL" << end << ": underlined black over red background" << std::endl;
std::ostringstream format;
clutchlog::fmt discreet(clutchlog::fmt::fg::white);
format << "{level}: "
<< discreet("{file}:")
<< clutchlog::fmt(clutchlog::fmt::fg::yellow) << "{line}"
<< clutchlog::fmt(clutchlog::fmt::typo::reset) << " {msg} ! " << std::endl;
log.format(format.str());
CLUTCHLOG(quiet,"After having inserted styles within a new format template");
}