fixes coverity identified issues (#4333)

4 files changed, 15 insertions, 6 deletions

diff --git a/src/common.c b/src/common.c
index eb5c4b7268..363ae2455a 100644
--- a/src/common.c
+++ b/src/common.c
@@ -1442,7 +1442,7 @@ char *strdupz_path_subpath(const char *path, const char *subpath) {
     while(len > 0 && path[len - 1] == '/') len--;
 
     // skip leading slashes in subpath
-    while(subpath && subpath[0] == '/') subpath++;
+    while(subpath[0] == '/') subpath++;
 
     // if the last character in path is / and (there is a subpath or path is now empty)
     // keep the trailing slash in path and remove the additional slash
@@ -1458,7 +1458,7 @@ char *strdupz_path_subpath(const char *path, const char *subpath) {
     }
 
     char buffer[FILENAME_MAX + 1];
-    snprintfz(buffer, FILENAME_MAX, "%.*s%s%s", (int)len, path, slash, (subpath)?subpath:"");
+    snprintfz(buffer, FILENAME_MAX, "%.*s%s%s", (int)len, path, slash, subpath);
     return strdupz(buffer);
 }
 
diff --git a/src/dictionary.h b/src/dictionary.h
index c872e2a810..058aab0e03 100644
--- a/src/dictionary.h
+++ b/src/dictionary.h
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
+#include "common.h"
+
 #ifndef NETDATA_DICTIONARY_H
 #define NETDATA_DICTIONARY_H 1
 
@@ -37,7 +39,7 @@ typedef struct dictionary {
 
 extern DICTIONARY *dictionary_create(uint8_t flags);
 extern void dictionary_destroy(DICTIONARY *dict);
-extern void *dictionary_set(DICTIONARY *dict, const char *name, void *value, size_t value_len);
+extern void *dictionary_set(DICTIONARY *dict, const char *name, void *value, size_t value_len) NEVERNULL;
 extern void *dictionary_get(DICTIONARY *dict, const char *name);
 extern int dictionary_del(DICTIONARY *dict, const char *name);
 
diff --git a/src/freeipmi_plugin.c b/src/freeipmi_plugin.c
index ad4dda139c..899a63d6fe 100644
--- a/src/freeipmi_plugin.c
+++ b/src/freeipmi_plugin.c
@@ -1529,8 +1529,8 @@ int main (int argc, char **argv) {
     int i, freq = 0;
     for(i = 1; i < argc ; i++) {
         if(isdigit(*argv[i]) && !freq) {
-            int n = atoi(argv[i]);
-            if(n > 0 && freq < 86400) {
+            int n = str2i(argv[i]);
+            if(n > 0 && n < 86400) {
                 freq = n;
                 continue;
             }
diff --git a/src/inlined.h b/src/inlined.h
index bd63271bfc..591b5adb08 100644
--- a/src/inlined.h
+++ b/src/inlined.h
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
+#include "common.h"
+
 #ifndef NETDATA_INLINED_H
 #define NETDATA_INLINED_H 1
 
@@ -245,12 +247,17 @@ static inline char *strncpyz(char *dst, const char *src, size_t n) {
 }
 
 static inline int read_file(const char *filename, char *buffer, size_t size) {
+    if(unlikely(!size)) return 3;
+
     int fd = open(filename, O_RDONLY, 0666);
-    if(unlikely(fd == -1))
+    if(unlikely(fd == -1)) {
+        buffer[0] = '\0';
         return 1;
+    }
 
     ssize_t r = read(fd, buffer, size);
     if(unlikely(r == -1)) {
+        buffer[0] = '\0';
         close(fd);
         return 2;
     }