From f50ada19dcd0dc6185dc4b410e721d46d1caba9f Mon Sep 17 00:00:00 2001
From: Sebastian Harl <sh@tokkee.org>
Date: Wed, 11 Feb 2009 11:31:30 +0100
Subject: [PATCH] Fixed various signedness issues identified by -Wextra.

The following two issues have been addressed:

 * comparison between signed and unsigned - this was found in several places
   throughout the code and has been fixed by switching to more appropriate
   types or adding appropriate explicit casts.
 * comparison of unsigned expression < 0 is always false - this was found in
   the processes and vserver plugins where a size_t had wrongly been used
   instead of a ssize_t and an int respectively.
---
 src/apache.c           |  2 +-
 src/ascent.c           | 10 +++++-----
 src/collectd-nagios.c  | 10 +++++-----
 src/common.c           |  2 +-
 src/configfile.c       |  4 ++--
 src/netlink.c          |  9 +++++----
 src/network.c          |  9 +++++----
 src/nginx.c            |  5 +++--
 src/plugin.c           | 10 ++++++----
 src/processes.c        |  2 +-
 src/snmp.c             | 12 ++++++------
 src/tail.c             |  4 ++--
 src/thermal.c          | 19 ++++++++++++-------
 src/utils_cache.c      |  2 +-
 src/utils_cmd_getval.c |  4 ++--
 src/utils_match.c      |  4 ++--
 src/utils_rrdcreate.c  | 11 +++++++----
 src/utils_subst.c      |  3 ++-
 src/utils_tail_match.c |  6 +++---
 src/vserver.c          | 10 +++++-----
 20 files changed, 76 insertions(+), 62 deletions(-)

diff --git a/src/apache.c b/src/apache.c
index 091d5947..4fa7aa1b 100644
--- a/src/apache.c
+++ b/src/apache.c
@@ -148,7 +148,7 @@ static int init (void)
 
 		status = ssnprintf (credentials, sizeof (credentials), "%s:%s",
 				user, (pass == NULL) ? "" : pass);
-		if (status >= sizeof (credentials))
+		if ((status < 0) || ((size_t) status >= sizeof (credentials)))
 		{
 			ERROR ("apache plugin: init: Returning an error "
 					"because the credentials have been "
diff --git a/src/ascent.c b/src/ascent.c
index 54341c77..8829e518 100644
--- a/src/ascent.c
+++ b/src/ascent.c
@@ -174,7 +174,7 @@ static size_t ascent_curl_callback (void *buf, size_t size, size_t nmemb, /* {{{
 
 static int ascent_submit_players (player_stats_t *ps) /* {{{ */
 {
-  int i;
+  size_t i;
   gauge_t value;
 
   for (i = 0; i < RACES_LIST_LENGTH; i++)
@@ -213,7 +213,7 @@ static int ascent_account_player (player_stats_t *ps, /* {{{ */
 {
   if (pi->race >= 0)
   {
-    if ((pi->race >= RACES_LIST_LENGTH)
+    if (((size_t) pi->race >= RACES_LIST_LENGTH)
         || (races_list[pi->race] == NULL))
       ERROR ("ascent plugin: Ignoring invalid numeric race %i.", pi->race);
     else
@@ -222,7 +222,7 @@ static int ascent_account_player (player_stats_t *ps, /* {{{ */
 
   if (pi->class >= 0)
   {
-    if ((pi->class >= CLASSES_LIST_LENGTH)
+    if (((size_t) pi->class >= CLASSES_LIST_LENGTH)
         || (classes_list[pi->class] == NULL))
       ERROR ("ascent plugin: Ignoring invalid numeric class %i.", pi->class);
     else
@@ -231,7 +231,7 @@ static int ascent_account_player (player_stats_t *ps, /* {{{ */
 
   if (pi->gender >= 0)
   {
-    if ((pi->gender >= GENDERS_LIST_LENGTH)
+    if (((size_t) pi->gender >= GENDERS_LIST_LENGTH)
         || (genders_list[pi->gender] == NULL))
       ERROR ("ascent plugin: Ignoring invalid numeric gender %i.",
           pi->gender);
@@ -549,7 +549,7 @@ static int ascent_init (void) /* {{{ */
 
     status = ssnprintf (credentials, sizeof (credentials), "%s:%s",
         user, (pass == NULL) ? "" : pass);
-    if (status >= sizeof (credentials))
+    if ((status < 0) || ((size_t) status >= sizeof (credentials)))
     {
       ERROR ("ascent plugin: ascent_init: Returning an error because the "
           "credentials have been truncated.");
diff --git a/src/collectd-nagios.c b/src/collectd-nagios.c
index b995b1c5..8f4a4105 100644
--- a/src/collectd-nagios.c
+++ b/src/collectd-nagios.c
@@ -165,7 +165,7 @@ static int filter_ds (size_t *values_num,
 		return (RET_UNKNOWN);
 	}
 
-	for (i = 0; i < match_ds_num_g; i++)
+	for (i = 0; i < (size_t) match_ds_num_g; i++)
 	{
 		size_t j;
 
@@ -298,7 +298,7 @@ static int do_check_con_none (size_t values_num,
 	int num_okay = 0;
 	const char *status_str = "UNKNOWN";
 	int status_code = RET_UNKNOWN;
-	int i;
+	size_t i;
 
 	for (i = 0; i < values_num; i++)
 	{
@@ -349,7 +349,7 @@ static int do_check_con_none (size_t values_num,
 static int do_check_con_average (size_t values_num,
 		double *values, char **values_names)
 {
-	int i;
+	size_t i;
 	double total;
 	int total_num;
 	double average;
@@ -402,7 +402,7 @@ static int do_check_con_average (size_t values_num,
 static int do_check_con_sum (size_t values_num,
 		double *values, char **values_names)
 {
-	int i;
+	size_t i;
 	double total;
 	int total_num;
 	const char *status_str = "UNKNOWN";
@@ -452,7 +452,7 @@ static int do_check_con_sum (size_t values_num,
 static int do_check_con_percentage (size_t values_num,
 		double *values, char **values_names)
 {
-	int i;
+	size_t i;
 	double sum = 0.0;
 	double percentage;
 
diff --git a/src/common.c b/src/common.c
index 7cc1d9d4..28f16da0 100644
--- a/src/common.c
+++ b/src/common.c
@@ -411,7 +411,7 @@ int check_create_dir (const char *file_orig)
 	char *saveptr;
 	int   last_is_file = 1;
 	int   path_is_absolute = 0;
-	int   len;
+	size_t len;
 	int   i;
 
 	/*
diff --git a/src/configfile.c b/src/configfile.c
index 0f49de26..bb1770d2 100644
--- a/src/configfile.c
+++ b/src/configfile.c
@@ -555,7 +555,7 @@ static oconfig_item_t *cf_read_dir (const char *dir, int depth)
 
 		status = ssnprintf (name, sizeof (name), "%s/%s",
 				dir, de->d_name);
-		if (status >= sizeof (name))
+		if ((status < 0) || ((size_t) status >= sizeof (name)))
 		{
 			ERROR ("configfile: Not including `%s/%s' because its"
 					" name is too long.",
@@ -630,7 +630,7 @@ static oconfig_item_t *cf_read_generic (const char *path, int depth)
 	int status;
 	const char *path_ptr;
 	wordexp_t we;
-	int i;
+	size_t i;
 
 	if (depth >= CF_MAX_DEPTH)
 	{
diff --git a/src/netlink.c b/src/netlink.c
index 8f45ea2e..b15768e7 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -246,7 +246,7 @@ static int link_filter (const struct sockaddr_nl __attribute__((unused)) *sa,
 
   /* Update the `iflist'. It's used to know which interfaces exist and query
    * them later for qdiscs and classes. */
-  if (msg->ifi_index >= iflist_len)
+  if ((msg->ifi_index >= 0) && ((size_t) msg->ifi_index >= iflist_len))
   {
     char **temp;
 
@@ -359,7 +359,8 @@ static int qos_filter (const struct sockaddr_nl __attribute__((unused)) *sa,
     return (0);
   }
 
-  if (msg->tcm_ifindex >= iflist_len)
+  if ((msg->tcm_ifindex >= 0)
+      && ((size_t) msg->tcm_ifindex >= iflist_len))
   {
     ERROR ("netlink plugin: qos_filter: msg->tcm_ifindex = %i "
 	">= iflist_len = %zu",
@@ -580,9 +581,9 @@ static int ir_read (void)
 
   /* `link_filter' will update `iflist' which is used here to iterate over all
    * interfaces. */
-  for (ifindex = 0; ifindex < iflist_len; ifindex++)
+  for (ifindex = 0; (size_t) ifindex < iflist_len; ifindex++)
   {
-    int type_index;
+    size_t type_index;
 
     if (iflist[ifindex] == NULL)
       continue;
diff --git a/src/network.c b/src/network.c
index e0800004..66f04380 100644
--- a/src/network.c
+++ b/src/network.c
@@ -498,7 +498,7 @@ static int parse_part_values (void **ret_buffer, int *ret_buffer_len,
 
 	exp_size = 3 * sizeof (uint16_t)
 		+ pkg_numval * (sizeof (uint8_t) + sizeof (value_t));
-	if (buffer_len < exp_size)
+	if ((buffer_len < 0) || ((size_t) buffer_len < exp_size))
 	{
 		WARNING ("network plugin: parse_part_values: "
 				"Packet too short: "
@@ -562,7 +562,7 @@ static int parse_part_number (void **ret_buffer, int *ret_buffer_len,
 	uint16_t pkg_length;
 	uint16_t pkg_type;
 
-	if (buffer_len < exp_size)
+	if ((buffer_len < 0) || ((size_t) buffer_len < exp_size))
 	{
 		WARNING ("network plugin: parse_part_number: "
 				"Packet too short: "
@@ -602,7 +602,7 @@ static int parse_part_string (void **ret_buffer, int *ret_buffer_len,
 	uint16_t pkg_length;
 	uint16_t pkg_type;
 
-	if (buffer_len < header_size)
+	if ((buffer_len < 0) || ((size_t) buffer_len < header_size))
 	{
 		WARNING ("network plugin: parse_part_string: "
 				"Packet too short: "
@@ -644,7 +644,8 @@ static int parse_part_string (void **ret_buffer, int *ret_buffer_len,
 	/* Check that the package data fits into the output buffer.
 	 * The previous if-statement ensures that:
 	 * `pkg_length > header_size' */
-	if ((pkg_length - header_size) > output_len)
+	if ((output_len < 0)
+			|| ((size_t) output_len < ((size_t) pkg_length - header_size)))
 	{
 		WARNING ("network plugin: parse_part_string: "
 				"Output buffer too small.");
diff --git a/src/nginx.c b/src/nginx.c
index dfa4f983..2de3633b 100644
--- a/src/nginx.c
+++ b/src/nginx.c
@@ -123,8 +123,9 @@ static int init (void)
 
   if (user != NULL)
   {
-    if (ssnprintf (credentials, sizeof (credentials),
-	  "%s:%s", user, pass == NULL ? "" : pass) >= sizeof (credentials))
+    int status = ssnprintf (credentials, sizeof (credentials),
+	"%s:%s", user, pass == NULL ? "" : pass);
+    if ((status < 0) || ((size_t) status >= sizeof (credentials)))
     {
       ERROR ("nginx plugin: Credentials would have been truncated.");
       return (-1);
diff --git a/src/plugin.c b/src/plugin.c
index 9d558cb1..61cc09c6 100644
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -328,6 +328,7 @@ int plugin_load (const char *type)
 	int   ret;
 	struct stat    statbuf;
 	struct dirent *de;
+	int status;
 
 	DEBUG ("type = %s", type);
 
@@ -336,8 +337,8 @@ int plugin_load (const char *type)
 
 	/* `cpu' should not match `cpufreq'. To solve this we add `.so' to the
 	 * type when matching the filename */
-	if (ssnprintf (typename, sizeof (typename),
-			"%s.so", type) >= sizeof (typename))
+	status = ssnprintf (typename, sizeof (typename), "%s.so", type);
+	if ((status < 0) || ((size_t) status >= sizeof (typename)))
 	{
 		WARNING ("snprintf: truncated: `%s.so'", type);
 		return (-1);
@@ -357,8 +358,9 @@ int plugin_load (const char *type)
 		if (strncasecmp (de->d_name, typename, typename_len))
 			continue;
 
-		if (ssnprintf (filename, sizeof (filename),
-				"%s/%s", dir, de->d_name) >= sizeof (filename))
+		status = ssnprintf (filename, sizeof (filename),
+				"%s/%s", dir, de->d_name);
+		if ((status < 0) || ((size_t) status >= sizeof (filename)))
 		{
 			WARNING ("snprintf: truncated: `%s/%s'", dir, de->d_name);
 			continue;
diff --git a/src/processes.c b/src/processes.c
index 553b1955..26dde3e4 100644
--- a/src/processes.c
+++ b/src/processes.c
@@ -821,7 +821,7 @@ static char *ps_get_cmdline (pid_t pid, char *name, char *buf, size_t buf_len)
 	n = 0;
 
 	while (42) {
-		size_t status;
+		ssize_t status;
 
 		status = read (fd, (void *)buf_ptr, len);
 
diff --git a/src/snmp.c b/src/snmp.c
index 82fd6583..998c4b64 100644
--- a/src/snmp.c
+++ b/src/snmp.c
@@ -530,9 +530,9 @@ static int csnmp_config_add_host_interval (host_definition_t *hd, oconfig_item_t
     return (-1);
   }
 
-  hd->interval = (int) ci->values[0].value.number;
-  if (hd->interval < 0)
-    hd->interval = 0;
+  hd->interval = ci->values[0].value.number >= 0
+    ? (uint32_t) ci->values[0].value.number
+    : 0;
 
   return (0);
 } /* int csnmp_config_add_host_interval */
@@ -1138,7 +1138,7 @@ static int csnmp_read_table (host_definition_t *host, data_definition_t *data)
       break;
     }
 
-    for (i = 0; i < oid_list_len; i++)
+    for (i = 0; (uint32_t) i < oid_list_len; i++)
       snmp_add_null_var (req, oid_list[i].oid, oid_list[i].oid_len);
 
     res = NULL;
@@ -1441,7 +1441,7 @@ static int csnmp_read_host (host_definition_t *host)
   time_end = time (NULL);
   DEBUG ("snmp plugin: csnmp_read_host (%s) finished at %u;", host->name,
       (unsigned int) time_end);
-  if ((time_end - time_start) > host->interval)
+  if ((uint32_t) (time_end - time_start) > host->interval)
   {
     WARNING ("snmp plugin: Host `%s' should be queried every %i seconds, "
 	"but reading all values takes %u seconds.",
@@ -1504,7 +1504,7 @@ static int csnmp_init (void)
     {
       host->interval = interval_g;
     }
-    else if (host->interval < interval_g)
+    else if (host->interval < (uint32_t) interval_g)
     {
       host->interval = interval_g;
       WARNING ("snmp plugin: Data for host `%s' will be collected every %i seconds.",
diff --git a/src/tail.c b/src/tail.c
index 01bf6292..3a98c60f 100644
--- a/src/tail.c
+++ b/src/tail.c
@@ -305,7 +305,7 @@ static int ctail_init (void)
 static int ctail_read (void)
 {
   int success = 0;
-  int i;
+  size_t i;
 
   for (i = 0; i < tail_match_list_num; i++)
   {
@@ -329,7 +329,7 @@ static int ctail_read (void)
 
 static int ctail_shutdown (void)
 {
-  int i;
+  size_t i;
 
   for (i = 0; i < tail_match_list_num; i++)
   {
diff --git a/src/thermal.c b/src/thermal.c
index 2ea6a24f..fe54aee4 100644
--- a/src/thermal.c
+++ b/src/thermal.c
@@ -71,8 +71,9 @@ static int thermal_sysfs_device_read (const char __attribute__((unused)) *dir,
 	if (device_list && ignorelist_match (device_list, name))
 		return -1;
 
-	len = snprintf (filename, sizeof (filename), "%s/%s/temp", dirname_sysfs, name);
-	if ((len < 0) || ((unsigned int)len >= sizeof (filename)))
+	len = snprintf (filename, sizeof (filename),
+			"%s/%s/temp", dirname_sysfs, name);
+	if ((len < 0) || ((size_t) len >= sizeof (filename)))
 		return -1;
 
 	len = read_file_contents (filename, data, sizeof(data));
@@ -90,8 +91,9 @@ static int thermal_sysfs_device_read (const char __attribute__((unused)) *dir,
 		}
 	}
 
-	len = snprintf (filename, sizeof (filename), "%s/%s/cur_state", dirname_sysfs, name);
-	if ((len < 0) || ((unsigned int)len >= sizeof (filename)))
+	len = snprintf (filename, sizeof (filename),
+			"%s/%s/cur_state", dirname_sysfs, name);
+	if ((len < 0) || ((size_t) len >= sizeof (filename)))
 		return -1;
 
 	len = read_file_contents (filename, data, sizeof(data));
@@ -128,12 +130,15 @@ static int thermal_procfs_device_read (const char __attribute__((unused)) *dir,
 	 * temperature:             55 C
 	 */
 	
-	len = snprintf (filename, sizeof (filename), "%s/%s/temperature", dirname_procfs, name);
-	if ((len < 0) || ((unsigned int)len >= sizeof (filename)))
+	len = snprintf (filename, sizeof (filename),
+			"%s/%s/temperature", dirname_procfs, name);
+	if ((len < 0) || ((size_t) len >= sizeof (filename)))
 		return -1;
 
 	len = read_file_contents (filename, data, sizeof(data));
-	if (len > sizeof(str_temp) && data[--len] == '\n' && !strncmp(data, str_temp, sizeof(str_temp)-1)) {
+	if ((len > 0) && ((size_t) len > sizeof(str_temp))
+			&& (data[--len] == '\n')
+			&& (! strncmp(data, str_temp, sizeof(str_temp)-1))) {
 		char *endptr = NULL;
 		double temp;
 		double celsius, add;
diff --git a/src/utils_cache.c b/src/utils_cache.c
index 824b7c80..b2f2c36b 100644
--- a/src/utils_cache.c
+++ b/src/utils_cache.c
@@ -522,7 +522,7 @@ gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl)
 
   /* This is important - the caller has no other way of knowing how many
    * values are returned. */
-  if (ret_num != ds->ds_num)
+  if (ret_num != (size_t) ds->ds_num)
   {
     ERROR ("utils_cache: uc_get_rate: ds[%s] has %i values, "
 	"but uc_get_rate_by_name returned %zu.",
diff --git a/src/utils_cmd_getval.c b/src/utils_cmd_getval.c
index 186ef9b5..ce3e28e0 100644
--- a/src/utils_cmd_getval.c
+++ b/src/utils_cmd_getval.c
@@ -51,7 +51,7 @@ int handle_getval (FILE *fh, char *buffer)
   const data_set_t *ds;
 
   int   status;
-  int   i;
+  size_t i;
 
   if ((fh == NULL) || (buffer == NULL))
     return (-1);
@@ -123,7 +123,7 @@ int handle_getval (FILE *fh, char *buffer)
     return (-1);
   }
 
-  if (ds->ds_num != values_num)
+  if ((size_t) ds->ds_num != values_num)
   {
     ERROR ("ds[%s]->ds_num = %i, "
 	"but uc_get_rate_by_name returned %u values.",
diff --git a/src/utils_match.c b/src/utils_match.c
index 906d7c70..c19c5ffc 100644
--- a/src/utils_match.c
+++ b/src/utils_match.c
@@ -50,7 +50,7 @@ static char *match_substr (const char *str, int begin, int end)
 
   if ((begin < 0) || (end < 0) || (begin >= end))
     return (NULL);
-  if (end > (strlen (str) + 1))
+  if ((size_t) end > (strlen (str) + 1))
   {
     ERROR ("utils_match: match_substr: `end' points after end of string.");
     return (NULL);
@@ -228,7 +228,7 @@ int match_apply (cu_match_t *obj, const char *str)
   regmatch_t re_match[32];
   char *matches[32];
   size_t matches_num;
-  int i;
+  size_t i;
 
   if ((obj == NULL) || (str == NULL))
     return (-1);
diff --git a/src/utils_rrdcreate.c b/src/utils_rrdcreate.c
index f006d13f..c4e9d8ba 100644
--- a/src/utils_rrdcreate.c
+++ b/src/utils_rrdcreate.c
@@ -148,12 +148,15 @@ static int rra_get (char ***ret, const value_list_t *vl, /* {{{ */
 
     for (j = 0; j < rra_types_num; j++)
     {
+      int status;
+
       if (rra_num >= rra_max)
         break;
 
-      if (ssnprintf (buffer, sizeof (buffer), "RRA:%s:%3.1f:%u:%u",
-            rra_types[j], cfg->xff,
-            cdp_len, cdp_num) >= sizeof (buffer))
+      status = ssnprintf (buffer, sizeof (buffer), "RRA:%s:%3.1f:%u:%u",
+          rra_types[j], cfg->xff, cdp_len, cdp_num);
+
+      if ((status < 0) || ((size_t) status >= sizeof (buffer)))
       {
         ERROR ("rra_get: Buffer would have been truncated.");
         continue;
@@ -236,7 +239,7 @@ static int ds_get (char ***ret, /* {{{ */
         d->name, type,
         (cfg->heartbeat > 0) ? cfg->heartbeat : (2 * vl->interval),
         min, max);
-    if ((status < 1) || (status >= sizeof (buffer)))
+    if ((status < 1) || ((size_t) status >= sizeof (buffer)))
       break;
 
     ds_def[ds_num] = sstrdup (buffer);
diff --git a/src/utils_subst.c b/src/utils_subst.c
index 640007c7..a49f6db5 100644
--- a/src/utils_subst.c
+++ b/src/utils_subst.c
@@ -37,7 +37,8 @@ char *subst (char *buf, size_t buflen, const char *string, int off1, int off2,
 			|| (NULL == replacement))
 		return NULL;
 
-	sstrncpy (buf_ptr, string, (off1 + 1 > buflen) ? buflen : off1 + 1);
+	sstrncpy (buf_ptr, string,
+			((size_t)off1 + 1 > buflen) ? buflen : (size_t)off1 + 1);
 	buf_ptr += off1;
 	len     -= off1;
 
diff --git a/src/utils_tail_match.c b/src/utils_tail_match.c
index ae1f4f75..22c79179 100644
--- a/src/utils_tail_match.c
+++ b/src/utils_tail_match.c
@@ -103,7 +103,7 @@ static int tail_callback (void *data, char *buf,
     int __attribute__((unused)) buflen)
 {
   cu_tail_match_t *obj = (cu_tail_match_t *) data;
-  int i;
+  size_t i;
 
   for (i = 0; i < obj->matches_num; i++)
     match_apply (obj->matches[i].match, buf);
@@ -135,7 +135,7 @@ cu_tail_match_t *tail_match_create (const char *filename)
 
 void tail_match_destroy (cu_tail_match_t *obj)
 {
-  int i;
+  size_t i;
 
   if (obj == NULL)
     return;
@@ -237,7 +237,7 @@ int tail_match_read (cu_tail_match_t *obj)
 {
   char buffer[4096];
   int status;
-  int i;
+  size_t i;
 
   status = cu_tail_read (obj->tail, buffer, sizeof (buffer), tail_callback,
       (void *) obj);
diff --git a/src/vserver.c b/src/vserver.c
index 8747d9ba..8fdae272 100644
--- a/src/vserver.c
+++ b/src/vserver.c
@@ -139,7 +139,7 @@ static int vserver_read (void)
 
 	while (42)
 	{
-		size_t len;
+		int len;
 		char file[BUFSIZE];
 
 		FILE *fh;
@@ -168,7 +168,7 @@ static int vserver_read (void)
 		if (dent->d_name[0] == '.')
 			continue;
 
-		len = snprintf (file, sizeof (file), PROCDIR "/%s", dent->d_name);
+		len = ssnprintf (file, sizeof (file), PROCDIR "/%s", dent->d_name);
 		if ((len < 0) || (len >= BUFSIZE))
 			continue;
 		
@@ -187,7 +187,7 @@ static int vserver_read (void)
 		/* socket message accounting */
 		len = ssnprintf (file, sizeof (file),
 				PROCDIR "/%s/cacct", dent->d_name);
-		if ((len < 0) || (len >= sizeof (file)))
+		if ((len < 0) || ((size_t) len >= sizeof (file)))
 			continue;
 
 		if (NULL == (fh = fopen (file, "r")))
@@ -235,7 +235,7 @@ static int vserver_read (void)
 		/* thread information and load */
 		len = ssnprintf (file, sizeof (file),
 				PROCDIR "/%s/cvirt", dent->d_name);
-		if ((len < 0) || (len >= sizeof (file)))
+		if ((len < 0) || ((size_t) len >= sizeof (file)))
 			continue;
 
 		if (NULL == (fh = fopen (file, "r")))
@@ -288,7 +288,7 @@ static int vserver_read (void)
 		/* processes and memory usage */
 		len = ssnprintf (file, sizeof (file),
 				PROCDIR "/%s/limit", dent->d_name);
-		if ((len < 0) || (len >= sizeof (file)))
+		if ((len < 0) || ((size_t) len >= sizeof (file)))
 			continue;
 
 		if (NULL == (fh = fopen (file, "r")))
-- 
2.11.0