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-rw-r--r--libblkid/lib/readutmp.c78
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diff --git a/libblkid/lib/readutmp.c b/libblkid/lib/readutmp.c
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+/* GNU's read utmp module.
+
+ Copyright (C) 1992-2001, 2003-2006, 2009-2014 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */
+
+/* Written by jla; revised by djm */
+/* extracted for util-linux by ooprala */
+
+#include <errno.h>
+#include <stdio.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#include "xalloc.h"
+#include "readutmp.h"
+
+/* Read the utmp entries corresponding to file FILE into freshly-
+ malloc'd storage, set *UTMP_BUF to that pointer, set *N_ENTRIES to
+ the number of entries, and return zero. If there is any error,
+ return -1, setting errno, and don't modify the parameters.
+ If OPTIONS & READ_UTMP_CHECK_PIDS is nonzero, omit entries whose
+ process-IDs do not currently exist. */
+int
+read_utmp (char const *file, size_t *n_entries, struct utmp **utmp_buf)
+{
+ size_t n_read = 0;
+ size_t n_alloc = 0;
+ struct utmp *utmp = NULL;
+ struct utmp *u;
+
+ /* Ignore the return value for now.
+ Solaris' utmpname returns 1 upon success -- which is contrary
+ to what the GNU libc version does. In addition, older GNU libc
+ versions are actually void. */
+ utmpname(file);
+
+ setutent();
+
+ errno = 0;
+ while ((u = getutent()) != NULL) {
+ if (n_read == n_alloc) {
+ n_alloc += 32;
+ utmp = xrealloc(utmp, n_alloc * sizeof (struct utmp));
+ if (!utmp)
+ return -1;
+ }
+ utmp[n_read++] = *u;
+ }
+ if (!u && errno) {
+ free(utmp);
+ return -1;
+ }
+
+ endutent();
+
+ *n_entries = n_read;
+ *utmp_buf = utmp;
+
+ return 0;
+}