--- /dev/null
+/*
+ * fincore - count pages of file contents in core
+ *
+ * Copyright (C) 2017 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 <sys/mman.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "c.h"
+#include "nls.h"
+#include "closestream.h"
+
+/* For large files, mmap is called in iterative way.
+ Window is the unit of vma prepared in each mmap
+ calling.
+
+ Window size depends on page size.
+ e.g. 128MB on x86_64. ( = N_PAGES_IN_WINDOW * 4096 ). */
+#define N_PAGES_IN_WINDOW (32 * 1024)
+
+static void __attribute__((__noreturn__)) usage(FILE *out)
+{
+ const char *p = program_invocation_short_name;
+
+ if (!*p)
+ p = "fincore";
+
+ fputs(USAGE_HEADER, out);
+ fprintf(out, _(" %s [options] file...\n"), program_invocation_short_name);
+ fputs(USAGE_OPTIONS, out);
+ fputs(USAGE_SEPARATOR, out);
+ fputs(USAGE_HELP, out);
+ fputs(USAGE_VERSION, out);
+ fprintf(out, USAGE_MAN_TAIL("fincore(1)"));
+ exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+}
+
+static void report_count (const char *name, off_t file_size, off_t count_incore)
+{
+ printf ("%-10lu %-10lu %s\n", count_incore, file_size, name);
+}
+
+static void report_failure (const char *name)
+{
+ printf ("%-10s %-10ld %s\n", "failed", -1L, name);
+}
+
+static int do_mincore (void *window, const size_t len,
+ const char *name, const int pagesize,
+ off_t *count_incore)
+{
+ static unsigned char vec[N_PAGES_IN_WINDOW];
+ int n = (len / pagesize) + ((len % pagesize)? 1: 0);
+
+ if (mincore (window, len, vec) < 0) {
+ warn(_("failed to do mincore: %s"), name);
+ return EXIT_FAILURE;
+ }
+
+ while (n > 0)
+ {
+ if (vec[--n] & 0x1)
+ {
+ vec[n] = 0;
+ (*count_incore)++;
+ }
+ }
+
+ return EXIT_SUCCESS;
+}
+
+static int fincore_fd (int fd,
+ const char *name, const int pagesize,
+ off_t file_size,
+ off_t *count_incore)
+{
+ size_t window_size = N_PAGES_IN_WINDOW * pagesize;
+ off_t file_offset;
+ void *window = NULL;
+ int r = EXIT_SUCCESS;
+ int warned_once = 0;
+
+ for (file_offset = 0; file_offset < file_size; file_offset += window_size) {
+ size_t len;
+
+ len = file_size - file_offset;
+ if (len >= window_size)
+ len = window_size;
+
+ window = mmap(window, len, PROT_NONE, MAP_PRIVATE, fd, file_offset);
+ if (window == MAP_FAILED) {
+ if (!warned_once) {
+ r = EXIT_FAILURE;
+ warn(_("failed to do mmap: %s"), name);
+ warned_once = 1;
+ }
+ break;
+ }
+
+ if (do_mincore (window, len, name, pagesize, count_incore) != EXIT_SUCCESS)
+ r = EXIT_FAILURE;
+
+ munmap (window, len);
+ }
+
+ return r;
+}
+
+static int fincore_name (const char *name,
+ const int pagesize, struct stat *sb,
+ off_t *count_incore)
+{
+ int fd;
+ int r;
+
+ if ((fd = open (name, O_RDONLY)) < 0) {
+ warn(_("failed to open: %s"), name);
+ return EXIT_FAILURE;
+ }
+
+ if (fstat (fd, sb) < 0) {
+ warn(_("failed to do fstat: %s"), name);
+ return EXIT_FAILURE;
+ }
+
+ if (sb->st_size)
+ r = fincore_fd (fd, name, pagesize, sb->st_size, count_incore);
+ else
+ /* If the file is empty,
+ we just report this file as "successful". */
+ r = EXIT_SUCCESS;
+
+ close (fd);
+
+ return r;
+}
+
+int main(int argc, char ** argv)
+{
+ int c;
+ int pagesize;
+ int r;
+
+ static const struct option longopts[] = {
+ { "version", no_argument, NULL, 'V' },
+ { "help", no_argument, NULL, 'h' },
+ { NULL, 0, NULL, 0 },
+ };
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ while ((c = getopt_long (argc, argv, "Vh", longopts, NULL)) != -1) {
+ switch (c) {
+ case 'V':
+ printf(UTIL_LINUX_VERSION);
+ return EXIT_SUCCESS;
+ case 'h':
+ usage(stdout);
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ if (optind == argc) {
+ warnx(_("file argument is missing"));
+ usage(stderr);
+ }
+
+
+ pagesize = getpagesize();
+ r = EXIT_SUCCESS;
+ for(; optind < argc; optind++) {
+ char *name = argv[optind];
+ struct stat sb;
+ off_t count_incore = 0;
+
+ if (fincore_name (name, pagesize, &sb, &count_incore) == EXIT_SUCCESS)
+ report_count (name, sb.st_size, count_incore);
+ else {
+ report_failure (name);
+ r = EXIT_FAILURE;
+ }
+ }
+
+ return r;
+}
projects / thirdparty / util-linux.git / commitdiff
