1 /* nproc - print the number of processors.
2 Copyright (C) 2009-2023 Free Software Foundation, Inc.
3
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* Written by Giuseppe Scrivano. */
18
19 #include <config.h>
20 #include <getopt.h>
21 #include <stdio.h>
22 #include <sys/types.h>
23
24 #include "system.h"
25 #include "nproc.h"
26 #include "quote.h"
27 #include "xdectoint.h"
28
29 /* The official name of this program (e.g., no 'g' prefix). */
30 #define PROGRAM_NAME "nproc"
31
32 #define AUTHORS proper_name ("Giuseppe Scrivano")
33
34 enum
35 {
36 ALL_OPTION = CHAR_MAX + 1,
37 IGNORE_OPTION
38 };
39
40 static struct option const longopts[] =
41 {
42 {"all", no_argument, nullptr, ALL_OPTION},
43 {"ignore", required_argument, nullptr, IGNORE_OPTION},
44 {GETOPT_HELP_OPTION_DECL},
45 {GETOPT_VERSION_OPTION_DECL},
46 {nullptr, 0, nullptr, 0}
47 };
48
49 void
usage(int status)50 usage (int status)
51 {
52 if (status != EXIT_SUCCESS)
53 emit_try_help ();
54 else
55 {
56 printf (_("Usage: %s [OPTION]...\n"), program_name);
57 fputs (_("\
58 Print the number of processing units available to the current process,\n\
59 which may be less than the number of online processors\n\
60 \n\
61 "), stdout);
62 fputs (_("\
63 --all print the number of installed processors\n\
64 --ignore=N if possible, exclude N processing units\n\
65 "), stdout);
66
67 fputs (HELP_OPTION_DESCRIPTION, stdout);
68 fputs (VERSION_OPTION_DESCRIPTION, stdout);
69 emit_ancillary_info (PROGRAM_NAME);
70 }
71 exit (status);
72 }
73
74 int
main(int argc,char ** argv)75 main (int argc, char **argv)
76 {
77 unsigned long nproc, ignore = 0;
78 initialize_main (&argc, &argv);
79 set_program_name (argv[0]);
80 setlocale (LC_ALL, "");
81 bindtextdomain (PACKAGE, LOCALEDIR);
82 textdomain (PACKAGE);
83
84 atexit (close_stdout);
85
86 enum nproc_query mode = NPROC_CURRENT_OVERRIDABLE;
87
88 while (true)
89 {
90 int c = getopt_long (argc, argv, "", longopts, nullptr);
91 if (c == -1)
92 break;
93 switch (c)
94 {
95 case_GETOPT_HELP_CHAR;
96
97 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
98
99 case ALL_OPTION:
100 mode = NPROC_ALL;
101 break;
102
103 case IGNORE_OPTION:
104 ignore = xdectoumax (optarg, 0, ULONG_MAX, "", _("invalid number"),0);
105 break;
106
107 default:
108 usage (EXIT_FAILURE);
109 }
110 }
111
112 if (argc != optind)
113 {
114 error (0, 0, _("extra operand %s"), quote (argv[optind]));
115 usage (EXIT_FAILURE);
116 }
117
118 nproc = num_processors (mode);
119
120 if (ignore < nproc)
121 nproc -= ignore;
122 else
123 nproc = 1;
124
125 printf ("%lu\n", nproc);
126
127 return EXIT_SUCCESS;
128 }
129