From a916ae72b89d0bcb5fe28d55def7327e8a1f6ce0 Mon Sep 17 00:00:00 2001
From: Ruben Kerkhof <ruben@rubenkerkhof.com>
Date: Sat, 25 Jul 2015 15:21:52 +0200
Subject: [PATCH] utils_mount: use reentrant getmntent_r when we can

Fixes #1162
---
 configure.ac      |  7 +++++++
 src/utils_mount.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+)

diff --git a/configure.ac b/configure.ac
index 6ee6e9a5..6a664e67 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1244,6 +1244,8 @@ have_getvfsstat="no"
 AC_CHECK_FUNCS(getvfsstat, [have_getvfsstat="yes"])
 have_listmntent="no"
 AC_CHECK_FUNCS(listmntent, [have_listmntent="yes"])
+have_getmntent_r="no"
+AC_CHECK_FUNCS(getmntent_r, [have_getmntent_r="yes"])
 
 have_getmntent="no"
 AC_CHECK_FUNCS(getmntent, [have_getmntent="c"])
@@ -5501,6 +5503,11 @@ then
 	plugin_df="yes"
 fi
 
+if test "x$c_cv_have_getmntent_r" = "xyes"
+then
+	plugin_df="yes"
+fi
+
 # Df plugin: Check if we have either `statfs' or `statvfs' second.
 if test "x$plugin_df" = "xyes"
 then
diff --git a/src/utils_mount.c b/src/utils_mount.c
index b63a81ad..afeb39e1 100644
--- a/src/utils_mount.c
+++ b/src/utils_mount.c
@@ -571,6 +571,64 @@ static cu_mount_t *cu_mount_gen_getmntent (void)
 #warn "This version of `getmntent' hat not yet been implemented!"
 /* #endif HAVE_SEQ_GETMNTENT */
 
+#elif HAVE_GETMNTENT_R
+static cu_mount_t *cu_mount_getmntent (void)
+{
+	FILE *fp;
+	struct mntent me;
+	char mntbuf[1024];
+
+	cu_mount_t *first = NULL;
+	cu_mount_t *last  = NULL;
+	cu_mount_t *new   = NULL;
+
+	DEBUG ("utils_mount: (void); COLLECTD_MNTTAB = %s", COLLECTD_MNTTAB);
+
+	if ((fp = setmntent (COLLECTD_MNTTAB, "r")) == NULL)
+	{
+		char errbuf[1024];
+		ERROR ("setmntent (%s): %s", COLLECTD_MNTTAB,
+				sstrerror (errno, errbuf, sizeof (errbuf)));
+		return (NULL);
+	}
+
+	while (getmntent_r (fp, &me, mntbuf, sizeof (mntbuf) ))
+	{
+		if ((new = malloc (sizeof (cu_mount_t))) == NULL)
+			break;
+		memset (new, '\0', sizeof (cu_mount_t));
+
+		/* Copy values from `struct mntent *' */
+		new->dir         = sstrdup (me.mnt_dir);
+		new->spec_device = sstrdup (me.mnt_fsname);
+		new->type        = sstrdup (me.mnt_type);
+		new->options     = sstrdup (me.mnt_opts);
+		new->device      = get_device_name (new->options);
+		new->next        = NULL;
+
+		DEBUG ("utils_mount: new = {dir = %s, spec_device = %s, type = %s, options = %s, device = %s}",
+				new->dir, new->spec_device, new->type, new->options, new->device);
+
+		/* Append to list */
+		if (first == NULL)
+		{
+			first = new;
+			last  = new;
+		}
+		else
+		{
+			last->next = new;
+			last       = new;
+		}
+	}
+
+	endmntent (fp);
+
+	DEBUG ("utils_mount: return (0x%p)", (void *) first);
+
+	return (first);
+} /* HAVE_GETMNTENT_R */
+
 #elif HAVE_ONE_GETMNTENT
 static cu_mount_t *cu_mount_getmntent (void)
 {
-- 
2.11.0