rnd.range was causing a crash when MIN is bigger than MAX. Error mess…

…age added.
selimanac · Aug 10, 2020 · 6213cc4 · 6213cc4
1 parent d591df6
commit 6213cc4
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Showing 3 changed files with 34 additions and 20 deletions.
diff --git a/README.md b/README.md
@@ -15,7 +15,7 @@ You can use PCG Random in your own project by adding this project as a [Defold l
 
 ## Usage
 
-### rnd.seed(`init_state, init_seq`)
+### rnd.seed(`init_state`, `init_seq`)
 
 Seeds the random number generator.   
 Random number generator is always initialized by using entropy seed. You don't need to call this method unless you want to control the seed.
@@ -35,7 +35,7 @@ Random number generator is always initialized by using entropy seed. You don’t
 
 Returns a 32 bit unsigned integer.
 
-### rnd.range(`min, max`)
+### rnd.range(`min`, `max`)
 
 Returns a 32 bit unsigned integer between min and max values. Only for positive numbers(unsigned integers).   
 Same as **math.random(3,20)**  
@@ -62,6 +62,10 @@ Testing entropy.
 
 ## Release Notes
 
+1.2.2
+
+- `rnd.range` was causing a crash when MIN is bigger than MAX. Error message added.
+
 1.2.1
 
 - Added static seed

diff --git a/main/main.script b/main/main.script
@@ -43,6 +43,9 @@ local function test()
         print("Result (unsigned int): " .. num)
     end
 
+    print("Error check:")
+    local z =  rnd.range(1, 0) 
+    print(z)
     print("--------------------")
 end
 

diff --git a/pcgrandom/src/pcgrandom.cpp b/pcgrandom/src/pcgrandom.cpp
@@ -67,6 +67,13 @@ static int range(lua_State *L)
     int top = lua_gettop(L);
     min = luaL_checknumber(L, 1);
     max = luaL_checknumber(L, 2);
+
+
+    if (min >= max) {
+        dmLogError("rnd.range: MAX(%i) must be bigger than MIN(%i)", max, min);
+        return 0;
+    }
+
     max++;
     num = pcg32_boundedrand_r(&rng, (max - min)) + min;
     lua_pushnumber(L, num);
@@ -112,12 +119,12 @@ static int check(lua_State *L)
     printf("\n");
 
     printf("pcg32_random_r:\n"
-           "      -  result:      32-bit unsigned int (uint32_t)\n"
-           "      -  period:      2^64   (* 2^63 streams)\n"
-           "      -  state type:  pcg32_random_t (%zu bytes)\n"
-           "      -  output func: XSH-RR\n"
-           "\n",
-           sizeof(pcg32_random_t));
+        "      -  result:      32-bit unsigned int (uint32_t)\n"
+        "      -  period:      2^64   (* 2^63 streams)\n"
+        "      -  state type:  pcg32_random_t (%zu bytes)\n"
+        "      -  output func: XSH-RR\n"
+        "\n",
+        sizeof(pcg32_random_t));
 
     for (round = 1; round <= rounds; ++round)
     {
@@ -163,9 +170,9 @@ static int check(lua_State *L)
         }
 
         printf("  Cards:");
-        static const char number[] = {'A', '2', '3', '4', '5', '6', '7',
-                                      '8', '9', 'T', 'J', 'Q', 'K'};
-        static const char suit[] = {'h', 'c', 'd', 's'};
+        static const char number[] ={ 'A', '2', '3', '4', '5', '6', '7',
+            '8', '9', 'T', 'J', 'Q', 'K' };
+        static const char suit[] ={ 'h', 'c', 'd', 's' };
         for (i = 0; i < CARDS; ++i)
         {
             printf(" %c%c", number[cards[i] / SUITS], suit[cards[i] % SUITS]);
@@ -179,16 +186,16 @@ static int check(lua_State *L)
 }
 
 static const luaL_reg Module_methods[] =
-    {
+{
 
-        {"seed", seedgen},
-        {"double", double_num},
-        {"roll", roll},
-        {"toss", toss},
-        {"range", range},
-        {"number", number},
-        {"check", check},
-        {0, 0}};
+    { "seed", seedgen },
+    { "double", double_num },
+    { "roll", roll },
+    { "toss", toss },
+    { "range", range },
+    { "number", number },
+    { "check", check },
+    { 0, 0 } };
 
 static void LuaInit(lua_State *L)
 {