check_snmp: Update last patch to copy value verbatim

Rework last patch, copying the converted portion of the string rather
than re-converting it. This is safer for backwards-compatibility as the
value is never modified.

diff --git a/plugins/check_snmp.c b/plugins/check_snmp.c
index ce3919d1af4f3592f08b3fa229cffe1102ce4bc5..fdb5819e05d443e5a71accbe5625e843b63b5989 100644 (file)
--- a/plugins/check_snmp.c
+++ b/plugins/check_snmp.c
@@ -117,12 +117,11 @@ int needmibs = FALSE;
 int
 main (int argc, char **argv)
 {
-       int i;
+       int i, len;
        int iresult = STATE_UNKNOWN;
        int result = STATE_UNKNOWN;
        int return_code = 0;
        int external_error = 0;
-       double perftmp;
        char **command_line = NULL;
        char *cl_hidden_auth = NULL;
        char *oidname = NULL;
@@ -352,17 +351,14 @@ main (int argc, char **argv)
                if (nunits > (size_t)0 && (size_t)i < nunits && unitv[i] != NULL)
                        asprintf (&outbuff, "%s %s", outbuff, unitv[i]);
 
-               /* Try a two-way conversion of show and add perfdata only if we get
-                * something back at the end */
+               /* Write perfdata with whatever can be parsed by strtod, if possible */
                ptr = NULL;
-               perftmp = strtod(show, &ptr);
-               if (ptr != show) {
-                       ptr = NULL;
-                       asprintf(&ptr, "%0.9g", perftmp);
+               strtod(show, &ptr);
+               if (ptr > show) {
                        strncat(perfstr, oidname, sizeof(perfstr)-strlen(perfstr)-1);
                        strncat(perfstr, "=", sizeof(perfstr)-strlen(perfstr)-1);
-                       strncat(perfstr, ptr, sizeof(perfstr)-strlen(perfstr)-1);
-                       free(ptr);
+                       len = sizeof(perfstr)-strlen(perfstr)-1;
+                       strncat(perfstr, show, len>ptr-show ? ptr-show : len);
 
                        if (type)
                                strncat(perfstr, type, sizeof(perfstr)-strlen(perfstr)-1);