add mutex debugging

diff --git a/d0.c b/d0.c
index fccc4e51326645b85f8725b9e8dc7c452cdbe5c2..0a246767d7fa9754320d3fe69071b8b52a4d5e5c 100644 (file)
--- a/d0.c
+++ b/d0.c
@@ -43,13 +43,49 @@ const char *d0_bsd_license_notice = "\n"
 
 #include <stdlib.h>
 
+#define MUTEX_DEBUG
+
 void *(*d0_malloc)(size_t len) = malloc;
 void (*d0_free)(void *p) = free;
 
-static void *dummy = (void *) 1; // some dummy non-NULL pointer
+#ifdef MUTEX_DEBUG
+#define NUM_MUTEXES 2
+#include <stdio.h>
+static mutexarray[NUM_MUTEXES];
+static int mutexpos = 0;
+static void *dummy_createmutex(void)
+{
+       if(mutexpos >= NUM_MUTEXES)
+       {
+               printf("We don't support creating so many mutexes here\n");
+               return NULL;
+       }
+       return &mutexarray[mutexpos++];
+}
+static void dummy_destroymutex(void *m)
+{
+       if(*(int *)m != 0)
+               printf("Destroying in-use mutex\n");
+       *(int *)m = -1;
+}
+static int dummy_lockmutex(void *m)
+{
+       if(*(int *)m != 0)
+               printf("Locking in-use mutex\n");
+       *(int *)m += 1;
+       return 0;
+}
+static int dummy_unlockmutex(void *m)
+{
+       if(*(int *)m != 1)
+               printf("Unlocking not-in-use mutex\n");
+       *(int *)m -= 1;
+       return 0;
+}
+#else
 static void *dummy_createmutex(void)
 {
-       return NULL;
+       return (void *) 1; // some dummy non-NULL pointer
 }
 static void dummy_destroymutex(void *m)
 {
@@ -62,6 +98,7 @@ static int dummy_unlockmutex(void *m)
 {
        return 0;
 }
+#endif
 
 void *(*d0_createmutex)(void) = dummy_createmutex;
 void (*d0_destroymutex)(void *) = dummy_destroymutex;