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Diffstat (limited to 'misc-utils/fadvise.c')
| -rw-r--r-- | misc-utils/fadvise.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/misc-utils/fadvise.c b/misc-utils/fadvise.c new file mode 100644 index 0000000..9606fb4 --- /dev/null +++ b/misc-utils/fadvise.c @@ -0,0 +1,162 @@ +/* + * fadvise - utility to use the posix_fadvise(2) + * + * Copyright (C) 2022 Red Hat, Inc. All rights reserved. + * Written by Masatake YAMATO <yamato@redhat.com> + * + * 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 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it would 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. + */ + +#include <fcntl.h> +#include <getopt.h> +#include <stdbool.h> +#include <stdio.h> + +#include "c.h" +#include "nls.h" +#include "strutils.h" + +static const struct advice { + const char *name; + int num; +} advices [] = { + { "normal", POSIX_FADV_NORMAL, }, + { "sequential", POSIX_FADV_SEQUENTIAL, }, + { "random", POSIX_FADV_RANDOM, }, + { "noreuse", POSIX_FADV_NOREUSE, }, + { "willneeded", POSIX_FADV_WILLNEED, }, + { "dontneed", POSIX_FADV_DONTNEED, }, +}; + +static void __attribute__((__noreturn__)) usage(void) +{ + FILE *out = stdout; + size_t i; + + fputs(USAGE_HEADER, out); + fprintf(out, _(" %s [options] file\n"), program_invocation_short_name); + fprintf(out, _(" %s [options] --fd|-d file-descriptor\n"), program_invocation_short_name); + + fputs(USAGE_OPTIONS, out); + fputs(_(" -a, --advice <advice> applying advice to the file (default: \"dontneed\")\n"), out); + fputs(_(" -l, --length <num> length for range operations, in bytes\n"), out); + fputs(_(" -o, --offset <num> offset for range operations, in bytes\n"), out); + + fputs(USAGE_SEPARATOR, out); + printf(USAGE_HELP_OPTIONS(23)); + + fputs(_("\nAvailable values for advice:\n"), out); + for (i = 0; i < ARRAY_SIZE(advices); i++) { + fprintf(out, " %s\n", + advices[i].name); + } + + printf(USAGE_MAN_TAIL("fadvise(1)")); + + exit(EXIT_SUCCESS); +} + +int main(int argc, char ** argv) +{ + int c; + int rc; + bool do_close = false; + + int fd = -1; + off_t offset = 0; + off_t len = 0; + int advice = POSIX_FADV_DONTNEED; + + static const struct option longopts[] = { + { "advice", required_argument, NULL, 'a' }, + { "fd", required_argument, NULL, 'd' }, + { "length", required_argument, NULL, 'l' }, + { "offset", required_argument, NULL, 'o' }, + { "version", no_argument, NULL, 'V' }, + { "help", no_argument, NULL, 'h' }, + { NULL, 0, NULL, 0 }, + }; + + setlocale(LC_ALL, ""); + bindtextdomain(PACKAGE, LOCALEDIR); + textdomain(PACKAGE); + + while ((c = getopt_long (argc, argv, "a:d:hl:o:V", longopts, NULL)) != -1) { + switch (c) { + case 'a': + advice = -1; + for (size_t i = 0; i < ARRAY_SIZE(advices); i++) { + if (strcmp(optarg, advices[i].name) == 0) { + advice = advices[i].num; + break; + } + } + if (advice == -1) + errx(EXIT_FAILURE, "invalid advice argument: '%s'", optarg); + break; + case 'd': + fd = strtos32_or_err(optarg, + _("invalid fd argument")); + break; + case 'l': + len = strtosize_or_err(optarg, + _("invalid length argument")); + break; + case 'o': + offset = strtosize_or_err(optarg, + _("invalid offset argument")); + break; + case 'V': + print_version(EXIT_SUCCESS); + case 'h': + usage(); + default: + errtryhelp(EXIT_FAILURE); + } + } + + if (optind == argc && fd == -1) { + warnx(_("no file specified")); + errtryhelp(EXIT_FAILURE); + } + + if (argc - optind > 0 && fd != -1) { + warnx(_("specify either file descriptor or file name")); + errtryhelp(EXIT_FAILURE); + } + + if (argc - optind > 1) { + warnx(_("specify one file descriptor or file name")); + errtryhelp(EXIT_FAILURE); + } + + if (fd == -1) { + fd = open(argv[optind], O_RDONLY); + if (fd < 0) + err(EXIT_FAILURE, _("cannot open %s"), argv[optind]); + do_close = true; + } + + rc = posix_fadvise(fd, + offset, len, + advice); + if (rc != 0) + warnx(_("failed to advise: %s"), strerror(rc)); + + if (do_close) + close(fd); + + return rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE; +} |