Automatic regex generation for testing

1 files changed, 178 insertions, 37 deletions

diff --git a/src/regex/test_regex.c b/src/regex/test_regex.c
index 7428c001e4..d32bc9ed8f 100644
--- a/src/regex/test_regex.c
+++ b/src/regex/test_regex.c
@@ -23,7 +23,7 @@
  * @author Maximilian Szengel
  */
 #include <regex.h>
-
+#include <time.h>
 #include "platform.h"
 #include "gnunet_regex_lib.h"
 
@@ -36,44 +36,164 @@ enum Match_Result
 struct Regex_String_Pair
 {
   char *regex;
-  char *string;
-  enum Match_Result expected_result;
+  int string_count;
+  char **strings;
+  enum Match_Result *expected_results;
 };
 
-
 int
-test_automaton (struct GNUNET_REGEX_Automaton *a, struct Regex_String_Pair *rxstr)
+test_random (unsigned int rx_length, unsigned int max_str_len, unsigned int str_count)
 {
+  int i;
+  int rx_exp;
+  char rand_rx[rx_length+1];
+  char matching_str[str_count][max_str_len+1];
+  char *rand_rxp;
+  char *matching_strp;
+  int char_op_switch;
+  int last_was_op;
+  char current_char;
+  int eval;
+  int eval_check;
+  struct GNUNET_REGEX_Automaton *dfa;
   regex_t rx;
+  regmatch_t matchptr[1];
+  int char_offset;
+  char error[200];
+  int result;
+
+  // At least one string is needed for matching
+  GNUNET_assert (str_count > 0);
+  // The string should be at least as long as the regex itself
+  GNUNET_assert (max_str_len >= rx_length);
+
+  rand_rxp = rand_rx;
+  matching_strp = matching_str[0];
+
+  // Generate random regex and a string that matches the regex
+  for (i=0; i<rx_length; i++)
+  {
+    char_op_switch = 0 + (int)(1.0 * rand() / (RAND_MAX + 1.0));
+    char_offset = (rand()%2) ? 65 : 97;
+
+    if (0 == char_op_switch
+        && !last_was_op)
+    {
+      last_was_op = 1;
+      rx_exp = rand () % 3;
+
+      switch (rx_exp)
+      {
+        case 0:
+          current_char = '+';
+          break;
+        case 1:
+          current_char = '*';
+          break;
+        case 2:
+          if (i < rx_length -1)
+            current_char = '|';
+          else
+            current_char = (char)(char_offset + (int)( 25.0 * rand() / (RAND_MAX + 1.0)));
+          break;
+      }
+    }
+    else
+    {
+      current_char = (char)(char_offset + (int)( 25.0 * rand() / (RAND_MAX + 1.0)));
+      last_was_op = 0;
+    }
+
+    if (current_char != '+'
+        && current_char != '*'
+        && current_char != '|')
+    {
+      *matching_strp = current_char;
+      matching_strp++;
+    }
+
+    *rand_rxp = current_char;
+    rand_rxp++;
+  }
+  *rand_rxp = '\0';
+  *matching_strp = '\0';
+
+  result = 0;
+
+  for (i=0; i<str_count; i++)
+  {
+    // Match string using DFA
+    dfa = GNUNET_REGEX_construct_dfa (rand_rx, strlen (rand_rx));
+    if (NULL == dfa)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Constructing DFA failed\n");
+      return -1;
+    }
+
+    eval = GNUNET_REGEX_eval (dfa, matching_str[i]);
+    GNUNET_REGEX_automaton_destroy (dfa);
+
+    // Match string using glibc regex
+    if (0 != regcomp (&rx, rand_rx, REG_EXTENDED))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not compile regex using regcomp\n");
+      return -1;
+    }
+
+    eval_check = regexec (&rx, matching_str[i], 1, matchptr, 0);
+
+    // We only want to match the whole string, because that's what our DFA does, too.
+    if (eval_check == 0 && (matchptr[0].rm_so != 0 || matchptr[0].rm_eo != strlen (matching_str[i])))
+      eval_check = 1;
+
+    // compare result
+    if (eval_check != eval)
+    {
+      regerror (eval_check, &rx, error, sizeof error);
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "Unexpected result:\nregex: %s\nstring: %s\ngnunet regex: %i\nglibc regex: %i\nglibc error: %s\n\n",
+                  rand_rx, matching_str, eval, eval_check, error);
+      result += 1;
+    }
+  }
+  return result;
+}
+
+int
+test_automaton (struct GNUNET_REGEX_Automaton *a, regex_t *rx, struct Regex_String_Pair *rxstr)
+{
   int result;
   int eval;
   int eval_check;
+  char error[200];
+  int i;
 
   if (NULL == a)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Automaton was NULL\n");
     return 1;
+  }
 
   result = 0;
 
-  eval = GNUNET_REGEX_eval (a, rxstr->string);
-  regcomp (&rx, rxstr->regex, REG_EXTENDED);
-  eval_check = regexec (&rx, rxstr->string, 0, NULL, 0);
-
-  if ((rxstr->expected_result == match
-       && (0 != eval || 0 != eval_check))
-      ||
-      (rxstr->expected_result == nomatch
-       && (0 == eval || 0 == eval_check)))
+  for (i=0; i<rxstr->string_count; i++)
   {
-      result = 1;
-      char error[200];
-      regerror (eval_check, &rx, error, sizeof error);
-      GNUNET_log (GNUNET_ERROR_TYPE_ERROR, 
-                  "Unexpected result:\nregex: %s\nstring: %s\nexpected result: %i\ngnunet regex: %i\nglibc regex: %i\nglibc error: %s\n\n", 
-                  rxstr->regex, rxstr->string, rxstr->expected_result, eval, eval_check, error);
-  }
-
-  regfree (&rx);
+    eval = GNUNET_REGEX_eval (a, rxstr->strings[i]);
+    eval_check = regexec (rx, rxstr->strings[i], 0, NULL, 0);
 
+    if ((rxstr->expected_results[i] == match
+         && (0 != eval || 0 != eval_check))
+        ||
+        (rxstr->expected_results[i] == nomatch
+         && (0 == eval || 0 == eval_check)))
+    {
+        result = 1;
+        regerror (eval_check, rx, error, sizeof error);
+        GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                    "Unexpected result:\nregex: %s\nstring: %s\nexpected result: %i\ngnunet regex: %i\nglibc regex: %i\nglibc error: %s\n\n",
+                    rxstr->regex, rxstr->strings[i], rxstr->expected_results[i], eval, eval_check, error);
+    }
+  }
   return result;
 }
 
@@ -90,34 +210,55 @@ main (int argc, char *argv[])
 
   int check_nfa;
   int check_dfa;
+  int check_rand;
   struct Regex_String_Pair rxstr[3];
   struct GNUNET_REGEX_Automaton *a;
+  regex_t rx;
   int i;
 
-  rxstr[0].regex = "ab(c|d)+c*(a(b|c)d)+";
-  rxstr[0].string = "abcdcdcdcdddddabd";
-  rxstr[0].expected_result = match;
+  check_nfa = 0;
+  check_dfa = 0;
+  check_rand = 0;
 
-  rxstr[1].regex = "a*";
-  rxstr[1].string = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
-  rxstr[1].expected_result = match;
-
-  rxstr[2].regex = "a*b*c*d+";
-  rxstr[2].string = "a";
-  rxstr[2].expected_result = nomatch;
+  rxstr[0].regex = "ab(c|d)+c*(a(b|c)d)+";
+  rxstr[0].string_count = 5;
+  rxstr[0].strings = GNUNET_malloc (sizeof (char *) * rxstr[0].string_count);
+  rxstr[0].strings[0] = "abcdcdcdcdddddabd";
+  rxstr[0].strings[1] = "abcd";
+  rxstr[0].strings[2] = "abcddddddccccccccccccccccccccccccabdacdabd";
+  rxstr[0].strings[3] = "abccccca";
+  rxstr[0].strings[4] = "abcdcdcdccdabdabd";
+  rxstr[0].expected_results = GNUNET_malloc (sizeof (enum Match_Result) * rxstr[0].string_count);
+  rxstr[0].expected_results[0] = match;
+  rxstr[0].expected_results[1] = nomatch;
+  rxstr[0].expected_results[2] = match;
+  rxstr[0].expected_results[3] = nomatch;
+  rxstr[0].expected_results[4] = match;
 
-  for (i=0; i<3; i++)
+  for (i=0; i<1; i++)
   {
+    if (0 != regcomp (&rx, rxstr->regex, REG_EXTENDED | REG_NOSUB))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not compile regex using regcomp()\n");
+      return 1;
+    }
+
     // NFA test
     a = GNUNET_REGEX_construct_nfa (rxstr[i].regex, strlen (rxstr[i].regex));
-    check_nfa += test_automaton (a, &rxstr[i]);
+    check_nfa += test_automaton (a, &rx, &rxstr[i]);
     GNUNET_REGEX_automaton_destroy (a);
 
     // DFA test
     a = GNUNET_REGEX_construct_dfa (rxstr[i].regex, strlen (rxstr[i].regex));
-    check_dfa += test_automaton (a, &rxstr[i]);
+    check_dfa += test_automaton (a, &rx, &rxstr[i]);
     GNUNET_REGEX_automaton_destroy (a);
+
+    regfree (&rx);
   }
 
-  return check_nfa + check_dfa;
+  srand (time(NULL));
+  for (i=0; i< 100; i++)
+    check_rand += test_random (100, 100, 1);
+
+  return check_nfa + check_dfa + check_rand;
 }