Initial commit

channel/channelapp/source/blob.c

@@ -0,0 +1,84 @@
+#include <ogcsys.h>
+#include <ogc/machine/processor.h>
+
+#include "../config.h"
+#include "debug.h"
+#include "panic.h"
+#include "blob.h"
+
+#define MAX_BLOBS 8
+#define BLOB_MINSLACK (512*1024)
+
+typedef struct {
+	void *the_blob;
+	size_t blob_size;
+	void *old_arena2hi;
+} blob_t;
+
+blob_t blobs[MAX_BLOBS];
+int num_blobs = 0;
+
+// supports only stack-type allocs (free last alloced)
+void *blob_alloc(size_t size)
+{
+	u32 level;
+	u32 addr;
+	void *old_arena2hi;
+
+	_CPU_ISR_Disable(level);
+	if (num_blobs >= MAX_BLOBS) {
+		_CPU_ISR_Restore(level);
+		gprintf("too many blobs\n");
+		panic();
+	}
+
+	old_arena2hi = SYS_GetArena2Hi();
+	addr = (((u32)old_arena2hi) - size) & (~0x1f);
+
+	if (addr < (BLOB_MINSLACK + (u32)SYS_GetArena2Lo())) {
+		_CPU_ISR_Restore(level);
+		return NULL;
+	}
+
+	blobs[num_blobs].old_arena2hi = old_arena2hi;
+	blobs[num_blobs].the_blob = (void*)addr;
+	blobs[num_blobs].blob_size = size;
+	num_blobs++;
+
+	SYS_SetArena2Hi((void*)addr);
+	_CPU_ISR_Restore(level);
+	gprintf("allocated blob size %d at 0x%08lx\n", size, addr);
+	return (void*)addr;
+}
+
+void blob_free(void *p)
+{
+	u32 level;
+	if (!p)
+		return;
+
+	_CPU_ISR_Disable(level);
+
+	if (num_blobs == 0) {
+		_CPU_ISR_Restore(level);
+		gprintf("blob_free with no blobs\n");
+		panic();
+	}
+
+	num_blobs--;
+	if (p != blobs[num_blobs].the_blob) {
+		_CPU_ISR_Restore(level);
+		gprintf("mismatched blob_free (%p != %p)\n", p, blobs[num_blobs].the_blob);
+		panic();
+	}
+	if (SYS_GetArena2Hi() != p) {
+		_CPU_ISR_Restore(level);
+		gprintf("someone else used MEM2 (%p != %p)\n", p, SYS_GetArena2Hi());
+		panic();
+	}
+
+	SYS_SetArena2Hi(blobs[num_blobs].old_arena2hi);
+	_CPU_ISR_Restore(level);
+	gprintf("freed blob size %d at %p\n", blobs[num_blobs].blob_size, p);
+}
+