softap: Fix for hostapd.conf corruption

SoftAP fails to load the default hostapd.conf file
which was left behind as part of failed attempt to
start the softAP. The default hostapd.conf is required
to be copied in case of accidental corruption of
hostapd.conf

Change-Id: I4e6ab7a6bc67fcdcfe225e7e1a811fafe402ebc7
CRs-Fixed: 626022

softap/sdk/qsap_api.c

@@ -3172,6 +3172,20 @@ int qsapsetSoftap(int argc, char *argv[])
     return 0;
 }
 
+
+static int check_for_config_file_size(FILE *fp)
+{
+   int length = 0;
+
+   if( NULL != fp )
+   {
+      fseek(fp, 0L, SEEK_END);
+      length = ftell(fp);
+   }
+
+   return length;
+}
+
 void check_for_configuration_files(void)
 {
     FILE * fp;
@@ -3184,6 +3198,11 @@ void check_for_configuration_files(void)
         wifi_qsap_reset_to_default(CONFIG_FILE, DEFAULT_CONFIG_FILE_PATH);
     }
     else {
+
+        /* The configuration file could be of 0 byte size, replace with default */
+        if (check_for_config_file_size(fp) <= 0)
+            wifi_qsap_reset_to_default(CONFIG_FILE, DEFAULT_CONFIG_FILE_PATH);
+
         fclose(fp);
     }
 
@@ -3192,6 +3211,11 @@ void check_for_configuration_files(void)
         wifi_qsap_reset_to_default(ACCEPT_LIST_FILE, DEFAULT_ACCEPT_LIST_FILE_PATH);
     }
     else {
+
+        /* The configuration file could be of 0 byte size, replace with default */
+        if (check_for_config_file_size(fp) <= 0)
+            wifi_qsap_reset_to_default(ACCEPT_LIST_FILE, DEFAULT_ACCEPT_LIST_FILE_PATH);
+
         fclose(fp);
     }
 
@@ -3200,6 +3224,11 @@ void check_for_configuration_files(void)
         wifi_qsap_reset_to_default(DENY_LIST_FILE, DEFAULT_DENY_LIST_FILE_PATH);
     }
     else {
+
+        /* The configuration file could be of 0 byte size, replace with default */
+        if (check_for_config_file_size(fp) <= 0)
+            wifi_qsap_reset_to_default(DENY_LIST_FILE, DEFAULT_DENY_LIST_FILE_PATH);
+
         fclose(fp);
     }