Improve error handling

3 files changed, 39 insertions, 12 deletions

diff --git a/cpufreq.c b/cpufreq.c
index d9e0e4e..75eb774 100644
--- a/cpufreq.c
+++ b/cpufreq.c
@@ -20,6 +20,7 @@ int cpufreq_set_str(char *parameter,char *value,int checkdelay)
 {
  int fd;
  char sysfs_file[128];
+ int done=0;
 
  DEBUG1_CPUFREQ("Set %s to %s\n",parameter,value)
 
@@ -66,11 +67,14 @@ int cpufreq_set_str(char *parameter,char *value,int checkdelay)
      DEBUG1_CPUFREQ("Failed to set %s\n",d->d_name);
      return -1;
     }
+    done++;
    }
    bpos+=d->d_reclen;
   } 
  }
  close(fd);
+
+ return done;
 }
 
 int cpufreq_set_long_int(char *parameter,long int value,int checkdelay)
@@ -78,5 +82,5 @@ int cpufreq_set_long_int(char *parameter,long int value,int checkdelay)
  char buf[255];
 
  snprintf(buf,255,"%ld",value);
- cpufreq_set_str(parameter,buf,checkdelay);
+ return cpufreq_set_str(parameter,buf,checkdelay);
 }
diff --git a/cputemp2maxfreq.c b/cputemp2maxfreq.c
index 6ea71bf..00d8f4f 100644
--- a/cputemp2maxfreq.c
+++ b/cputemp2maxfreq.c
@@ -57,7 +57,7 @@ int main()
  }
 
 // Set the governor
- if (cpufreq_set_str("scaling_governor",config.governor,0)!=0)
+ if (cpufreq_set_str("scaling_governor",config.governor,0)<0)
  {
   printf("Failed to set governor, error %d (%s).\n",errno,strerror(errno));
 
@@ -84,24 +84,48 @@ int main()
 
   DEBUG1_MAIN("Data: %ld %ld %ld %ld %ld\n",cpudata.cur_temp,config.max_temp,cpudata.max_freq,cpudata.scale_max,cpudata.cur_freq);
 
+// Check if we should increase
   if ((cpudata.cur_temp<config.max_temp) && (cpudata.scale_max<cpudata.max_freq))
   {
    diff=(config.max_temp-cpudata.cur_temp)/1000;
    newfreq=cpudata.scale_max+(config.freq_step*diff);
    if (newfreq>cpudata.max_freq) newfreq=cpudata.max_freq;
    DEBUG1_MAIN("Increase to %ld\n",newfreq);
-   cpufreq_set_long_int("scaling_max_freq",newfreq,100);
+
+// Set new value and validate
+   if (cpufreq_set_long_int("scaling_max_freq",newfreq,100)<0)
+   {
+    printf("Failed to set scaling_max_freq, exiting.\n");
+    failsafe(1);
+   }
    cpudata.scale_max=sysfs_read_long_int("/sys/devices/system/cpu/cpufreq/policy0/scaling_max_freq");
+   if ((cpudata.scale_max<VALID_FREQ_MIN) || (cpudata.scale_max>VALID_FREQ_MAX))
+   {
+    printf("Invalid scale_max_freq reported, exiting,\n");
+    failsafe(1);
+   }
   }
 
+// Check if we should decrease
   if ((cpudata.cur_temp>config.max_temp) && (cpudata.scale_max>cpudata.min_freq))
   {
    diff=(cpudata.cur_temp-config.max_temp)/1000;
    newfreq=cpudata.scale_max-(config.freq_step*diff);
    if (newfreq<cpudata.min_freq) newfreq=cpudata.min_freq;
    DEBUG1_MAIN("Decrease to %ld\n",newfreq);
-   cpufreq_set_long_int("scaling_max_freq",newfreq,100);
+
+// Set new value and validate
+   if (cpufreq_set_long_int("scaling_max_freq",newfreq,100)<0)
+   {
+    printf("Failed to set scaling_max_freq, exiting.\n");
+    failsafe(1);
+   }
    cpudata.scale_max=sysfs_read_long_int("/sys/devices/system/cpu/cpufreq/policy0/scaling_max_freq");
+   if ((cpudata.scale_max<VALID_FREQ_MIN) || (cpudata.scale_max>VALID_FREQ_MAX))
+   {
+    printf("Invalid scale_max_freq reported, exiting,\n");
+    failsafe(1);
+   }
   }
 
   sleep(config.interval);
diff --git a/failsafe.c b/failsafe.c
index 3b9fe48..fec00e8 100644
--- a/failsafe.c
+++ b/failsafe.c
@@ -10,24 +10,23 @@ extern struct s_config config;
 
 void failsafe(int code)
 {
- printf("Failed to set governor, error %d (%s).\n",errno,strerror(errno));
-
-// We failed to set the governor, try to fail safe. First try the CPU minimum
-// frequency, if that doesn't work out try the fallback frequency
- if (cpufreq_set_long_int("scaling_max_freq",cpudata.min_freq,100)==0)
+// First try to set the CPU to it's minimum frequency
+ if (cpufreq_set_long_int("scaling_max_freq",cpudata.min_freq,100)>0)
  {
-  printf("Set scaling frequency to CPU's minimum frequency.");
+  printf("Set scaling frequency to CPU's minimum frequency.\n");
   exit(code);
  }
  printf("Failed to set scaling frequency to CPU's minimum frequency, error: %d (%s).\n",errno,strerror(errno));
 
- if (cpufreq_set_long_int("scaling_max_freq",config.fallback_freq,100)==0)
+// If that failed, try the fallback frequency
+ if (cpufreq_set_long_int("scaling_max_freq",config.fallback_freq,100)>0)
  {
-  printf("Set scaling frequency to fallback frequency.");
+  printf("Set scaling frequency to fallback frequency.\n");
   exit(code);
  }
  printf("Failed to set scaling frequency to fallback frequency, error: %d (%s).\n",errno,strerror(errno));
 
+// Everything failed, issue a warning 
  printf("All safety measures failed, watch out not to fry your hardware.\n");
  exit(code);
 }