1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
#pragma once
///@file
#include <limits>
#include <string>
namespace nix {
enum class StandardOutputStream {
Stdout = 1,
Stderr = 2,
};
/**
* Determine whether the output is a real terminal (i.e. not dumb, not a pipe).
*
* This is probably not what you want, you may want shouldANSI() or something
* more specific. Think about how the output should work with a pager or
* entirely non-interactive scripting use.
*
* The user may be redirecting the Lix output to a pager, but have stderr
* connected to a terminal. Think about where you are outputting the text when
* deciding whether to use STDERR_FILENO or STDOUT_FILENO.
*
* \param fileno file descriptor number to check if it is a tty
*/
bool isOutputARealTerminal(StandardOutputStream fileno);
/**
* Determine whether ANSI escape sequences are appropriate for the
* present output.
*
* This follows the rules described on https://bixense.com/clicolors/
* with CLICOLOR defaulted to enabled (and thus ignored).
*
* That is to say, the following procedure is followed in order:
* - NO_COLOR or NOCOLOR set -> always disable colour
* - CLICOLOR_FORCE or FORCE_COLOR set -> enable colour
* - The output is a tty; TERM != "dumb" -> enable colour
* - Otherwise -> disable colour
*
* \param fileno which file descriptor number to consider. Use the one you are outputting to
*/
bool shouldANSI(StandardOutputStream fileno = StandardOutputStream::Stderr);
/**
* Truncate a string to 'width' printable characters. If 'filterAll'
* is true, all ANSI escape sequences are filtered out. Otherwise,
* some escape sequences (such as colour setting) are copied but not
* included in the character count. Also, tabs are expanded to
* spaces.
*/
std::string filterANSIEscapes(std::string_view s,
bool filterAll = false,
unsigned int width = std::numeric_limits<unsigned int>::max(),
bool eatTabs = true);
/**
* Recalculate the window size, updating a global variable. Used in the
* `SIGWINCH` signal handler.
*/
void updateWindowSize();
/**
* @return the number of rows and columns of the terminal.
*
* The value is cached so this is quick. The cached result is computed
* by `updateWindowSize()`.
*/
std::pair<unsigned short, unsigned short> getWindowSize();
}
|
