Merge pull request #385 from ccin2p3/libvirt-plugin-instance

[collectd.git] / src / common.c

diff --git a/src/common.c b/src/common.c
index 81142fd..1608d52 100644 (file)
--- a/src/common.c
+++ b/src/common.c
@@ -377,8 +377,10 @@ int strunescape (char *buf, size_t buf_len)
                if (buf[i] != '\\')
                        continue;
 
-               if ((i >= buf_len) || (buf[i + 1] == '\0')) {
+               if (((i + 1) >= buf_len) || (buf[i + 1] == 0)) {
                        ERROR ("string unescape: backslash found at end of string.");
+                       /* Ensure null-byte at the end of the buffer. */
+                       buf[i] = 0;
                        return (-1);
                }
 
@@ -397,7 +399,10 @@ int strunescape (char *buf, size_t buf_len)
                                break;
                }
 
+               /* Move everything after the position one position to the left.
+                * Add a null-byte as last character in the buffer. */
                memmove (buf + i + 1, buf + i + 2, buf_len - i - 2);
+               buf[buf_len - 1] = 0;
        }
        return (0);
 } /* int strunescape */
@@ -650,7 +655,7 @@ int get_kstat (kstat_t **ksp_ptr, char *module, int instance, char *name)
        char ident[128];
 
        *ksp_ptr = NULL;
-       
+
        if (kc == NULL)
                return (-1);
 
@@ -1236,7 +1241,7 @@ int walk_directory (const char *dir, dirwalk_callback_f callback,
        while ((ent = readdir (dh)) != NULL)
        {
                int status;
-               
+
                if (include_hidden)
                {
                        if ((strcmp (".", ent->d_name) == 0)
@@ -1399,6 +1404,69 @@ int rate_to_value (value_t *ret_value, gauge_t rate, /* {{{ */
        return (0);
 } /* }}} value_t rate_to_value */
 
+int value_to_rate (value_t *ret_rate, derive_t value, /* {{{ */
+               value_to_rate_state_t *state,
+               int ds_type, cdtime_t t)
+{
+       double interval;
+
+       /* Another invalid state: The time is not increasing. */
+       if (t <= state->last_time)
+       {
+               memset (state, 0, sizeof (*state));
+               return (EINVAL);
+       }
+
+       interval = CDTIME_T_TO_DOUBLE(t - state->last_time);
+
+       /* Previous value is invalid. */
+       if (state->last_time == 0) /* {{{ */
+       {
+               if (ds_type == DS_TYPE_DERIVE)
+               {
+                       state->last_value.derive = value;
+               }
+               else if (ds_type == DS_TYPE_COUNTER)
+               {
+                       state->last_value.counter = (counter_t) value;
+               }
+               else if (ds_type == DS_TYPE_ABSOLUTE)
+               {
+                       state->last_value.absolute = (absolute_t) value;
+               }
+               else
+               {
+                       assert (23 == 42);
+               }
+
+               state->last_time = t;
+               return (EAGAIN);
+       } /* }}} */
+
+       if (ds_type == DS_TYPE_DERIVE)
+       {
+               ret_rate->gauge = (value - state->last_value.derive) / interval;
+               state->last_value.derive = value;
+       }
+       else if (ds_type == DS_TYPE_COUNTER)
+       {
+               ret_rate->gauge = (((counter_t)value) - state->last_value.counter) / interval;
+               state->last_value.counter = (counter_t) value;
+       }
+       else if (ds_type == DS_TYPE_ABSOLUTE)
+       {
+               ret_rate->gauge = (((absolute_t)value) - state->last_value.absolute) / interval;
+               state->last_value.absolute = (absolute_t) value;
+       }
+       else
+       {
+               assert (23 == 42);
+       }
+
+        state->last_time = t;
+       return (0);
+} /* }}} value_t rate_to_value */
+
 int service_name_to_port_number (const char *service_name)
 {
        struct addrinfo *ai_list;