diff options
Diffstat (limited to 'src/nice.c')
| -rw-r--r-- | src/nice.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/src/nice.c b/src/nice.c new file mode 100644 index 0000000..19b38bc --- /dev/null +++ b/src/nice.c @@ -0,0 +1,195 @@ +/* nice -- run a program with modified niceness + Copyright (C) 1990-2005 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* David MacKenzie <djm@gnu.ai.mit.edu> */ + +#include <config.h> +#include <stdio.h> +#include <getopt.h> +#include <sys/types.h> + +#include "system.h" + +#if ! HAVE_NICE +/* Include this after "system.h" so we're sure to have definitions + (from time.h or sys/time.h) required for e.g. the ru_utime member. */ +# include <sys/resource.h> +#endif + +#include "error.h" +#include "long-options.h" +#include "quote.h" +#include "xstrtol.h" + +/* The official name of this program (e.g., no `g' prefix). */ +#define PROGRAM_NAME "nice" + +#define AUTHORS "David MacKenzie" + +#if HAVE_NICE +# define GET_NICENESS() nice (0) +#else +# define GET_NICENESS() getpriority (PRIO_PROCESS, 0) +#endif + +#ifndef NZERO +# define NZERO 20 +#endif + +/* This is required for Darwin Kernel Version 7.7.0. */ +#if NZERO == 0 +# undef NZERO +# define NZERO 20 +#endif + +/* The name this program was run with. */ +char *program_name; + +static struct option const longopts[] = +{ + {"adjustment", required_argument, NULL, 'n'}, + {NULL, 0, NULL, 0} +}; + +void +usage (int status) +{ + if (status != EXIT_SUCCESS) + fprintf (stderr, _("Try `%s --help' for more information.\n"), + program_name); + else + { + printf (_("Usage: %s [OPTION] [COMMAND [ARG]...]\n"), program_name); + printf (_("\ +Run COMMAND with an adjusted niceness, which affects process scheduling.\n\ +With no COMMAND, print the current niceness. Nicenesses range from\n\ +%d (most favorable scheduling) to %d (least favorable).\n\ +\n\ + -n, --adjustment=N add integer N to the niceness (default 10)\n\ +"), + - NZERO, NZERO - 1); + fputs (HELP_OPTION_DESCRIPTION, stdout); + fputs (VERSION_OPTION_DESCRIPTION, stdout); + printf (USAGE_BUILTIN_WARNING, PROGRAM_NAME); + printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT); + } + exit (status); +} + +int +main (int argc, char **argv) +{ + int current_niceness; + int adjustment = 10; + char const *adjustment_given = NULL; + bool ok; + int i; + + initialize_main (&argc, &argv); + program_name = argv[0]; + setlocale (LC_ALL, ""); + bindtextdomain (PACKAGE, LOCALEDIR); + textdomain (PACKAGE); + + initialize_exit_failure (EXIT_FAIL); + atexit (close_stdout); + + parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION, + usage, AUTHORS, (char const *) NULL); + + for (i = 1; i < argc; /* empty */) + { + char const *s = argv[i]; + + if (s[0] == '-' && ISDIGIT (s[1 + (s[1] == '-' || s[1] == '+')])) + { + adjustment_given = s + 1; + ++i; + } + else + { + int optc; + int fake_argc = argc - (i - 1); + char **fake_argv = argv + (i - 1); + + /* Ensure that any getopt diagnostics use the right name. */ + fake_argv[0] = program_name; + + /* Initialize getopt_long's internal state. */ + optind = 0; + + optc = getopt_long (fake_argc, fake_argv, "+n:", longopts, NULL); + i += optind - 1; + + if (optc == '?') + usage (EXIT_FAIL); + else if (optc == 'n') + adjustment_given = optarg; + else /* optc == -1 */ + break; + } + } + + if (adjustment_given) + { + /* If the requested adjustment is outside the valid range, + silently bring it to just within range; this mimics what + "setpriority" and "nice" do. */ + enum { MIN_ADJUSTMENT = 1 - 2 * NZERO, MAX_ADJUSTMENT = 2 * NZERO - 1 }; + long int tmp; + if (LONGINT_OVERFLOW < xstrtol (adjustment_given, NULL, 10, &tmp, "")) + error (EXIT_FAIL, 0, _("invalid adjustment %s"), + quote (adjustment_given)); + adjustment = MAX (MIN_ADJUSTMENT, MIN (tmp, MAX_ADJUSTMENT)); + } + + if (i == argc) + { + if (adjustment_given) + { + error (0, 0, _("a command must be given with an adjustment")); + usage (EXIT_FAIL); + } + /* No command given; print the niceness. */ + errno = 0; + current_niceness = GET_NICENESS (); + if (current_niceness == -1 && errno != 0) + error (EXIT_FAIL, errno, _("cannot get niceness")); + printf ("%d\n", current_niceness); + exit (EXIT_SUCCESS); + } + + errno = 0; +#if HAVE_NICE + ok = (nice (adjustment) != -1 || errno == 0); +#else + current_niceness = GET_NICENESS (); + if (current_niceness == -1 && errno != 0) + error (EXIT_FAIL, errno, _("cannot get niceness")); + ok = (setpriority (PRIO_PROCESS, 0, current_niceness + adjustment) == 0); +#endif + if (!ok) + error (errno == EPERM ? 0 : EXIT_FAIL, errno, _("cannot set niceness")); + + execvp (argv[i], &argv[i]); + + { + int exit_status = (errno == ENOENT ? EXIT_ENOENT : EXIT_CANNOT_INVOKE); + error (0, errno, "%s", argv[i]); + exit (exit_status); + } +} |