Add lovrCheck macro;

lovrCheck is a new way of performing runtime assertions.

It's identical to lovrAssert, except it's compiled out if
LOVR_UNCHECKED is defined.

It is meant to be used for non-mission-critical validation, for
example proper usage of types passed to the Lua API.  lovrAssert
should still be used to check return values from platform APIs.

src/core/util.c

@@ -1,20 +1,13 @@
 #include "util.h"
 #include <stdlib.h>
-#include <stdio.h>
 #include <stdatomic.h>
 
 // Error handling
-static void defaultErrorCallback(void* p, const char* format, va_list args) {
-  fprintf(stderr, "Error: ");
-  vfprintf(stderr, format, args);
-  fprintf(stderr, "\n");
-}
-
-LOVR_THREAD_LOCAL errorFn* lovrErrorCallback = defaultErrorCallback;
-LOVR_THREAD_LOCAL void* lovrErrorUserdata = NULL;
+static LOVR_THREAD_LOCAL errorFn* lovrErrorCallback;
+static LOVR_THREAD_LOCAL void* lovrErrorUserdata;
 
 void lovrSetErrorCallback(errorFn* callback, void* userdata) {
-  lovrErrorCallback = callback ? callback : defaultErrorCallback;
+  lovrErrorCallback = callback;
   lovrErrorUserdata = userdata;
 }
 

src/core/util.h

@@ -33,12 +33,16 @@ typedef struct Color { float r, g, b, a; } Color;
 
 // Error handling
 typedef void errorFn(void*, const char*, va_list);
-extern LOVR_THREAD_LOCAL errorFn* lovrErrorCallback;
-extern LOVR_THREAD_LOCAL void* lovrErrorUserdata;
 void lovrSetErrorCallback(errorFn* callback, void* userdata);
 void LOVR_NORETURN lovrThrow(const char* format, ...);
 #define lovrAssert(c, ...) if (!(c)) { lovrThrow(__VA_ARGS__); }
 
+#ifdef LOVR_UNCHECKED
+#define lovrCheck(c, ...) ((void) 0)
+#else
+#define lovrCheck lovrAssert
+#endif
+
 // Logging
 typedef void logFn(void*, int, const char*, const char*, va_list);
 enum { LOG_DEBUG, LOG_INFO, LOG_WARN, LOG_ERROR };

src/main.c

@@ -32,7 +32,10 @@ int main(int argc, char** argv) {
     exit(0);
   }
 
-  lovrAssert(os_init(), "Failed to initialize platform");
+  if (!os_init()) {
+    fprintf(stderr, "Failed to initialize platform");
+    exit(1);
+  }
 
   int status;
   bool restart;