1// Copyright 2019 The Rust Project Developers. See the COPYRIGHT
2// file at the top-level directory of this distribution and at
3// http://rust-lang.org/COPYRIGHT.
4//
5// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8// option. This file may not be copied, modified, or distributed
9// except according to those terms.
10
11//! ncurses-compatible database discovery
12//!
13//! Does not support hashed database, only filesystem!
14
15use std::env;
16use std::fs;
17use std::path::PathBuf;
18
19use dirs_next as dirs;
20
21/// Return path to database entry for `term`
22pub fn get_dbpath_for_term(term: &str) -> Option<PathBuf> {
23 let mut dirs_to_search = Vec::new();
24 let first_char = match term.chars().next() {
25 Some(c) => c,
26 None => return None,
27 };
28
29 // Find search directory
30 // The terminfo manual says:
31 //
32 // > If the environment variable TERMINFO is set, it is interpreted
33 // > as the pathname of a directory containing the compiled description
34 // > you are working on. Only that directory is searched.
35 //
36 // However, the ncurses manual says:
37 //
38 // > If the environment variable TERMINFO is defined, any program using
39 // > curses checks for a local terminal definition before checking in
40 // > the standard place.
41 //
42 // Given that ncurses is the defacto standard, we follow the ncurses manual.
43 if let Some(dir) = env::var_os("TERMINFO") {
44 dirs_to_search.push(PathBuf::from(dir));
45 }
46
47 if let Ok(dirs) = env::var("TERMINFO_DIRS") {
48 for i in dirs.split(':') {
49 if i == "" {
50 dirs_to_search.push(PathBuf::from("/usr/share/terminfo"));
51 } else {
52 dirs_to_search.push(PathBuf::from(i));
53 }
54 }
55 } else {
56 // Found nothing in TERMINFO_DIRS, use the default paths:
57 // According to /etc/terminfo/README, after looking at
58 // ~/.terminfo, ncurses will search /etc/terminfo, then
59 // /lib/terminfo, and eventually /usr/share/terminfo.
60 // On Haiku the database can be found at /boot/system/data/terminfo
61 if let Some(mut homedir) = dirs::home_dir() {
62 homedir.push(".terminfo");
63 dirs_to_search.push(homedir)
64 }
65
66 dirs_to_search.push(PathBuf::from("/etc/terminfo"));
67 dirs_to_search.push(PathBuf::from("/lib/terminfo"));
68 dirs_to_search.push(PathBuf::from("/usr/share/terminfo"));
69 dirs_to_search.push(PathBuf::from("/boot/system/data/terminfo"));
70 }
71
72 // Look for the terminal in all of the search directories
73 for mut p in dirs_to_search {
74 if fs::metadata(&p).is_ok() {
75 p.push(&first_char.to_string());
76 p.push(&term);
77 if fs::metadata(&p).is_ok() {
78 return Some(p);
79 }
80 p.pop();
81 p.pop();
82
83 // on some installations the dir is named after the hex of the char
84 // (e.g. OS X)
85 p.push(&format!("{:x}", first_char as usize));
86 p.push(term);
87 if fs::metadata(&p).is_ok() {
88 return Some(p);
89 }
90 }
91 }
92 None
93}
94