twister

commit 3ea91942f5dd739ccccee2ff2d996081003d654a
parent c5a65df2f40125fdd7d35f29822038d0d93fc5b5
Author: Marcello Stanisci <stanisci.m@gmail.com>
Date:   Mon,  4 Jun 2018 10:40:18 +0200

Addressing #5336.

Diffstat:
M
src/twister/taler-twister-service.c
 | 
30
++++++++++++++++++++++++------

1 file changed, 24 insertions(+), 6 deletions(-)
diff --git a/src/twister/taler-twister-service.c b/src/twister/taler-twister-service.c
@@ -918,6 +918,13 @@ flip_object (struct MHD_Connection *con,
 {
   char *target;
   json_t *parent;
+  #define CROCKFORD_MAX_INDEX 31
+  char crockford_chars[] = {'0', '1', '2', '3', '4', '5',
+                            '6', '7', '8', '9', 'A', 'B',
+                            'C', 'D', 'E', 'F', 'G', 'H',
+                            'J', 'K', 'M', 'N', 'P', 'Q',
+                            'R', 'S', 'T', 'V', 'W', 'X',
+                            'Y', 'Z'}; // index: 0-31
 
   if (GNUNET_OK != walk_response_object (flip_path,
                                          &parent,
@@ -930,7 +937,8 @@ flip_object (struct MHD_Connection *con,
   json_t *child = NULL;
   const char *current_value;
   char *current_value_flip;
-  uint32_t index;
+  uint32_t crockford_index;
+  uint32_t flip_index;
 
   if (json_is_object (parent))
     child = json_object_get (parent, target);
@@ -949,11 +957,19 @@ flip_object (struct MHD_Connection *con,
 
   #warning When free this?
   current_value_flip = GNUNET_strdup (current_value);
-  index = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
-                                    strlen (current_value_flip));
+  crockford_index = GNUNET_CRYPTO_random_u32
+    (GNUNET_CRYPTO_QUALITY_WEAK,
+     CROCKFORD_MAX_INDEX + 1);
 
-  /* flip the LSB.  */
-  current_value_flip[index] ^= 1;
+  flip_index = GNUNET_CRYPTO_random_u32
+    (GNUNET_CRYPTO_QUALITY_WEAK,
+     strlen (current_value_flip));
+
+  /* flip the LSB.  WARNING: if the flipping does NOT
+   * reach a Crockford-friendly char, then the test cases
+   * will get disoriented by "400 Bad request" responses.  */
+  current_value_flip[flip_index] =
+    crockford_chars[crockford_index];
 
   TALER_LOG_INFO ("Flipping %s to %s\n",
                   current_value,
@@ -1413,7 +1429,9 @@ create_response (void *cls,
   {
     TALER_LOG_DEBUG ("Will flip path: %s\n",
                      flip_path_dl);
-    flip_object (con, hr->json, flip_path_dl);
+    flip_object (con,
+                 hr->json,
+                 flip_path_dl);
   }
 
   if ('\0' != delete_path[0])