coverity: Use a better random number generator for goom.

MythTV · Sep 3, 2020 · c44aa18 · c44aa18
1 parent 6f1c2fc
commit c44aa18
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Showing 4 changed files with 15 additions and 13 deletions.
diff --git a/mythtv/libs/libmythtv/visualisations/goom/goom_core.cpp b/mythtv/libs/libmythtv/visualisations/goom/goom_core.cpp
@@ -7,6 +7,7 @@
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <random>
 
 #include "goom_core.h"
 #include "goom_tools.h"
@@ -87,9 +88,7 @@ void goom_init (guint32 resx, guint32 resy, int cinemascope) {
         srand ((uintptr_t) pixel);
         if (!rand_tab) rand_tab = (int *) malloc (NB_RAND * sizeof(int)) ;
         rand_pos = 1 ;
-        // Pseudo-random is good enough. Don't need a true random.
-        // NOLINTNEXTLINE(cert-msc30-c,cert-msc50-cpp)
-        while (rand_pos != 0) rand_tab [rand_pos++] = rand () ;
+        while (rand_pos != 0) rand_tab [rand_pos++] = goom_rand () ;
 
 	cycle = 0;
 
@@ -978,3 +977,10 @@ void update_message (char *message) {
 	}
 }
 */
+
+guint32 goom_rand (void)
+{
+    static std::random_device rd;
+    static std::mt19937 mt(rd());
+    return mt();
+}
diff --git a/mythtv/libs/libmythtv/visualisations/goom/goom_core.h b/mythtv/libs/libmythtv/visualisations/goom/goom_core.h
@@ -21,5 +21,6 @@ MTV_PUBLIC void goom_set_resolution (guint32 resx, guint32 resy, int cinemascope
  */
 MTV_PUBLIC guint32 *goom_update (GoomDualData& data, int forceMode);
 MTV_PUBLIC void    goom_close (void);
+MTV_PUBLIC guint32 goom_rand (void);
 
 #endif // GOOMCORE_H
diff --git a/mythtv/libs/libmythtv/visualisations/goom/ifs.cpp b/mythtv/libs/libmythtv/visualisations/goom/ifs.cpp
@@ -41,6 +41,7 @@
 #include <cstdlib>
 
 #include "ifs.h"
+#include "goom_core.h"
 
 #define MODE_ifs
 
@@ -279,9 +280,7 @@ init_ifs (int width, int height)
 	Fractal->m_count = 0;
 	Fractal->m_lx = (Fractal->m_width - 1) / 2;
 	Fractal->m_ly = (Fractal->m_height - 1) / 2;
-	// Pseudo-random is good enough. Don't need a true random.
-	// NOLINTNEXTLINE(cert-msc30-c,cert-msc50-cpp)
-	Fractal->m_col = rand () % (width * height);	/* modif by JeKo */
+	Fractal->m_col = goom_rand () % (width * height);	/* modif by JeKo */
 
 	Random_Simis (Fractal, Fractal->m_components, 0, 5 * MAX_SIMI);
 

diff --git a/mythtv/libs/libmythtv/visualisations/goom/tentacle3d.cpp b/mythtv/libs/libmythtv/visualisations/goom/tentacle3d.cpp
@@ -29,14 +29,10 @@ void tentacle_new (void) {
 	vals = (float*)malloc ((definitionx+20)*sizeof(float));
 
 	for (auto & tmp : grille) {
-		// Pseudo-random is good enough. Don't need a true random.
-		// NOLINTNEXTLINE(cert-msc30-c,cert-msc50-cpp)
-		int z = 45+rand()%30;
-		// NOLINTNEXTLINE(cert-msc30-c,cert-msc50-cpp)
-		int x = 85+rand()%5;
+		int z = 45+goom_rand()%30;
+		int x = 85+goom_rand()%5;
 		center.z = z;
-		// NOLINTNEXTLINE(cert-msc30-c,cert-msc50-cpp)
-		tmp = grid3d_new (x,definitionx,z,definitionz+rand()%10,center);
+		tmp = grid3d_new (x,definitionx,z,definitionz+goom_rand()%10,center);
 		center.y += 8;
 	}
 }