Fix test prob distr parameters that caused warnings.

They were causing the following warnings in circuitpadding/circuitpadding_sample_distribution:

     src/lib/math/prob_distr.c:1311:17: runtime error: division by zero
     SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior src/lib/math/prob_distr.c:1311:17 in
     src/lib/math/prob_distr.c:1219:49: runtime error: division by zero
     SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior src/lib/math/prob_distr.c:1219:49 in

because the distributions were called with erroneous parameters (e.g. geometric
distribution with p=0).

We now defined these test probability distributions with more realistic
parameters.

As far as the circuitpadding_sample_distribution() test is concerned, it
doesn't matter if the distributions return values outside of [0,10] since we
already restrict the values into that interval using min=0 and max=10 (and RTT
estimate is disabled).

1 files changed, 10 insertions, 1 deletions

diff --git a/src/core/or/circuitpadding.h b/src/core/or/circuitpadding.h
index 74f9f35c98..fefdf2ba94 100644
--- a/src/core/or/circuitpadding.h
+++ b/src/core/or/circuitpadding.h
@@ -198,14 +198,23 @@ typedef enum {
  * These can be used instead of histograms for the inter-packet
  * timing distribution, or to specify a distribution on the number
  * of cells that can be sent while in a specific state of the state
- * machine. */
+ * machine.
+ *
+ * Each distribution takes up to two parameters which are described below. */
 typedef enum {
+  /* No probability distribution is used */
   CIRCPAD_DIST_NONE = 0,
+  /* Uniform distribution: param1 is lower bound and param2 is upper bound */
   CIRCPAD_DIST_UNIFORM = 1,
+  /* Logistic distribution: param1 is Mu, param2 is sigma. */
   CIRCPAD_DIST_LOGISTIC = 2,
+  /* Log-logistic distribution: param1 is Alpha, param2 is 1.0/Beta */
   CIRCPAD_DIST_LOG_LOGISTIC = 3,
+  /* Geometric distribution: param1 is 'p' (success probability) */
   CIRCPAD_DIST_GEOMETRIC = 4,
+  /* Weibull distribution: param1 is k, param2 is Lambda */
   CIRCPAD_DIST_WEIBULL = 5,
+  /* Generalized Pareto distribution: param1 is sigma, param2 is xi */
   CIRCPAD_DIST_PARETO = 6
 } circpad_distribution_type_t;