Fix some errors reported by Coverity (#6797)

* coverity_20190905: Fix reported bugs

This commit has fixes for some bugs reported by Coverity in the present day

* coverity_20190905: Fix missing report

FIx a missing report of error

* coverity_20190905: Pipe close

The previous fix had an error that wolud allow a socket continue opened, this commit fixes this

* coverity_20190905: Error pattern

The call of perror would generate a different error report, instead I am using strerror() to keep pattern

* coverity_20190905: Error function

Rewrite the call to error function

* coverity_20190905: Fix missing tests

The previous fix did not have correct tests after to clean the variables

* coverity_20190905: Fix readable

I changed for an else instead a new if, it is more clean this way

* coverity_20190905: remove unecessary test

This commit is removing an unecessary test for a variable that will never be NULL.

* coverity_20190905: Add neccessary NULLL

After to clean the variable, I am setting NULL to variable to avoid clean again

* coverity_20190905: Remove false error

The condition added to fix Coverity was generating false positives, so we are changing to debug

* coverity_20190905: Remove false error

The condition added to fix Coverity was generating false positives, so we are changing to debug

* coverity_20190905: Bring else to avoid error

Bring an else to solve the problem to read a FD not opened

* coverity_20190905: Return

After to analyse the last changes, I decided to return, because they were not necessary

* coverity_20190905: Remove NULL

Remove unecessary set of variable to NULL

1 files changed, 18 insertions, 20 deletions

diff --git a/health/health.c b/health/health.c
index 1460b5ba48..ed43b146c2 100644
--- a/health/health.c
+++ b/health/health.c
@@ -45,32 +45,30 @@ inline char *health_stock_config_dir(void) {
  * Function used to initialize the silencer structure.
  */
 void health_silencers_init(void) {
-    struct stat statbuf;
-    if (!stat(silencers_filename,&statbuf)) {
-        off_t length = statbuf.st_size;
+    FILE *fd = fopen(silencers_filename, "r");
+    if (fd) {
+        fseek(fd, 0 , SEEK_END);
+        off_t length = (off_t) ftell(fd);
+        fseek(fd, 0 , SEEK_SET);
+
         if (length && length < HEALTH_SILENCERS_MAX_FILE_LEN) {
-            FILE *fd = fopen(silencers_filename, "r");
-            if (fd) {
-                char *str = mallocz((length+1)* sizeof(char));
-                if(str) {
-                    size_t copied;
-                    copied = fread(str, sizeof(char), length, fd);
-                    if (copied == (length* sizeof(char))) {
-                        str[length] = 0x00;
-                        json_parse(str, NULL, health_silencers_json_read_callback);
-                        info("Parsed health silencers file %s", silencers_filename);
-                    } else {
-                        error("Cannot read the data from health silencers file %s", silencers_filename);
-                    }
-                    freez(str);
+            char *str = mallocz((length+1)* sizeof(char));
+            if(str) {
+                size_t copied;
+                copied = fread(str, sizeof(char), length, fd);
+                if (copied == (length* sizeof(char))) {
+                    str[length] = 0x00;
+                    json_parse(str, NULL, health_silencers_json_read_callback);
+                    info("Parsed health silencers file %s", silencers_filename);
+                } else {
+                    error("Cannot read the data from health silencers file %s", silencers_filename);
                 }
-                fclose(fd);
-            } else {
-                error("Cannot open the file %s",silencers_filename);
+                freez(str);
             }
         } else {
             error("Health silencers file %s has the size %ld that is out of range[ 1 , %d ]. Aborting read.", silencers_filename, length, HEALTH_SILENCERS_MAX_FILE_LEN);
         }
+        fclose(fd);
     } else {
         error("Cannot open the file %s",silencers_filename);
     }