Added new parameter to -P

3 files changed, 66 insertions, 35 deletions

diff --git a/src/include/ndpi_api.h b/src/include/ndpi_api.h
index 12387cd70..97ae56b86 100644
--- a/src/include/ndpi_api.h
+++ b/src/include/ndpi_api.h
@@ -906,7 +906,11 @@ extern "C" {
   float ndpi_data_entropy(struct ndpi_analyze_struct *s);
   float ndpi_data_variance(struct ndpi_analyze_struct *s);
   float ndpi_data_stddev(struct ndpi_analyze_struct *s);
+  u_int32_t ndpi_data_min(struct ndpi_analyze_struct *s);
+  u_int32_t ndpi_data_max(struct ndpi_analyze_struct *s);
   float ndpi_data_ratio(u_int32_t sent, u_int32_t rcvd);
+  
+  
   const char* ndpi_data_ratio2str(float ratio);
   
   void ndpi_data_print_window_values(struct ndpi_analyze_struct *s); /* debug */
diff --git a/src/include/ndpi_typedefs.h b/src/include/ndpi_typedefs.h
index 9ffb2d5c4..679cb3993 100644
--- a/src/include/ndpi_typedefs.h
+++ b/src/include/ndpi_typedefs.h
@@ -1380,7 +1380,7 @@ typedef struct {
 
 struct ndpi_analyze_struct {
   u_int32_t *values;
-  u_int32_t sum_total, num_data_entries, next_value_insert_index;
+  u_int32_t min_val, max_val, sum_total, num_data_entries, next_value_insert_index;
   u_int16_t num_values_array_len /* lenght of the values array */;
 
   struct {
diff --git a/src/lib/ndpi_analyze.c b/src/lib/ndpi_analyze.c
index eb36cb516..68f6a7aeb 100644
--- a/src/lib/ndpi_analyze.c
+++ b/src/lib/ndpi_analyze.c
@@ -46,15 +46,17 @@ struct ndpi_analyze_struct* ndpi_init_data_analysis(u_int16_t _max_series_len) {
     memset(ret, 0, sizeof(struct ndpi_analyze_struct));
   
   if(_max_series_len > MAX_SERIES_LEN) _max_series_len = MAX_SERIES_LEN;
-  if(_max_series_len == 0)             _max_series_len = 1; /* At least 1 element */
   ret->num_values_array_len = _max_series_len;
 
-  len = sizeof(u_int32_t)*ret->num_values_array_len;
-  if((ret->values = ndpi_malloc(len)) == NULL) {
-    ndpi_free(ret);
-    ret = NULL;
+  if(ret->num_values_array_len > 0) {
+    len = sizeof(u_int32_t)*ret->num_values_array_len;
+    if((ret->values = ndpi_malloc(len)) == NULL) {
+      ndpi_free(ret);
+      ret = NULL;
+    } else
+      memset(ret->values, 0, len);
   } else
-    memset(ret->values, 0, len);
+    ret->values = NULL;
   
   return(ret);
 }
@@ -62,7 +64,7 @@ struct ndpi_analyze_struct* ndpi_init_data_analysis(u_int16_t _max_series_len) {
 /* ********************************************************************************* */
 
 void ndpi_free_data_analysis(struct ndpi_analyze_struct *d) {
-  ndpi_free(d->values);
+  if(d->values) ndpi_free(d->values);
   ndpi_free(d);
 }
 
@@ -74,11 +76,22 @@ void ndpi_free_data_analysis(struct ndpi_analyze_struct *d) {
 void ndpi_data_add_value(struct ndpi_analyze_struct *s, const u_int32_t value) {
   float tmp_mu;
 
-  s->sum_total += value, s->num_data_entries++, s->values[s->next_value_insert_index] = value;
+  if(s->sum_total == 0)
+    s->min_val = s->max_val = value;
+  else {
+    if(value < s->min_val) s->min_val = value;
+    if(value > s->max_val) s->max_val = value;
+  }
 
-  if(++s->next_value_insert_index == s->num_values_array_len)
-    s->next_value_insert_index = 0;
+  s->sum_total += value, s->num_data_entries++;
+  
+  if(s->num_values_array_len) {
+    s->values[s->next_value_insert_index] = value;
 
+    if(++s->next_value_insert_index == s->num_values_array_len)
+      s->next_value_insert_index = 0;
+  }
+  
   /* Update stddev */
   tmp_mu = s->stddev.mu;
   s->stddev.mu = ((s->stddev.mu * (s->num_data_entries - 1)) + value) / s->num_data_entries;
@@ -94,6 +107,12 @@ float ndpi_data_average(struct ndpi_analyze_struct *s) {
 
 /* ********************************************************************************* */
 
+/* Return min/max on all values */
+u_int32_t ndpi_data_min(struct ndpi_analyze_struct *s) { return(s->min_val); }
+u_int32_t ndpi_data_max(struct ndpi_analyze_struct *s) { return(s->max_val); }
+
+/* ********************************************************************************* */
+
 /* Compute the variance on all values */
 float ndpi_data_variance(struct ndpi_analyze_struct *s) {
   return(s->num_data_entries ? (s->stddev.q / s->num_data_entries) : 0);
@@ -110,13 +129,16 @@ float ndpi_data_stddev(struct ndpi_analyze_struct *s) {
 
 /* Compute the average only on the sliding window */
 float ndpi_data_window_average(struct ndpi_analyze_struct *s) {
-  float   sum = 0.0;
-  u_int16_t i, n = ndpi_min(s->num_data_entries, s->num_values_array_len);
+  if(s->num_values_array_len) {
+    float   sum = 0.0;
+    u_int16_t i, n = ndpi_min(s->num_data_entries, s->num_values_array_len);
     
-  for(i=0; i<n; i++)
-    sum += s->values[i];
-
-  return((float)sum / (float)n);
+    for(i=0; i<n; i++)
+      sum += s->values[i];
+    
+    return((float)sum / (float)n);
+  } else
+    return(0);
 }
 
 /* ********************************************************************************* */
@@ -125,31 +147,36 @@ float ndpi_data_window_average(struct ndpi_analyze_struct *s) {
   Compute entropy on the last sliding window values
 */
 float ndpi_data_entropy(struct ndpi_analyze_struct *s) {
-  int i;
-  float sum = 0.0, total = 0.0;
-
-  for(i=0; i<s->num_values_array_len; i++)
-    total += s->values[i];
+  if(s->num_values_array_len) {
+    int i;
+    float sum = 0.0, total = 0.0;
     
-  for (i=0; i<s->num_values_array_len; i++) {
-    float tmp = (float)s->values[i] / (float)total;
+    for(i=0; i<s->num_values_array_len; i++)
+      total += s->values[i];
     
-    if(tmp > FLT_EPSILON)
-      sum -= tmp * logf(tmp);    
-  }
-  
-  return(sum / logf(2.0));
+    for (i=0; i<s->num_values_array_len; i++) {
+      float tmp = (float)s->values[i] / (float)total;
+      
+      if(tmp > FLT_EPSILON)
+	sum -= tmp * logf(tmp);    
+    }
+    
+    return(sum / logf(2.0));
+  } else
+    return(0);
 }
 
 /* ********************************************************************************* */
 
 void ndpi_data_print_window_values(struct ndpi_analyze_struct *s) {
-  u_int16_t i, n = ndpi_min(s->num_data_entries, s->num_values_array_len);
-  
-  for(i=0; i<n; i++)
-    printf("[%u: %u]", i, s->values[i]);
-
-  printf("\n");
+  if(s->num_values_array_len) {
+    u_int16_t i, n = ndpi_min(s->num_data_entries, s->num_values_array_len);
+    
+    for(i=0; i<n; i++)
+      printf("[%u: %u]", i, s->values[i]);
+    
+    printf("\n");
+  }
 }
 
 /* ********************************************************************************* */