map parsing code added

src/game/map_parser.c

@@ -0,0 +1,58 @@
+#include <ultra64.h>
+#include <PR/os_internal_error.h>
+#include <stdarg.h>
+#include <string.h>
+#include "segments.h"
+
+struct MapEntry {
+	u32 addr;
+	u32 nm_offset;
+	u32 nm_len;
+	u32 pad;
+};
+extern u8 gMapStrings[];
+extern struct MapEntry gMapEntries[];
+extern u32 gMapEntrySize;
+extern u8 _mapDataSegmentRomStart[];
+
+u8 *gMapStringAddr;
+struct MapEntry *gMapEntryAddr;
+
+// code provided by Wiseguy
+static s32 headless_dma(u32 devAddr, void *dramAddr, u32 size)
+{
+    register u32 stat;
+    stat = IO_READ(PI_STATUS_REG);
+	while (stat & (PI_STATUS_IO_BUSY | PI_STATUS_DMA_BUSY)) {
+	    stat = IO_READ(PI_STATUS_REG);
+	}
+    IO_WRITE(PI_DRAM_ADDR_REG, K0_TO_PHYS(dramAddr));
+    IO_WRITE(PI_CART_ADDR_REG, K1_TO_PHYS((u32)osRomBase | devAddr));
+    IO_WRITE(PI_WR_LEN_REG, size - 1);
+    return 0;
+}
+static u32 headless_pi_status(void)
+{
+    return IO_READ(PI_STATUS_REG);
+}
+// end of code provided by Wiseguy
+
+
+void map_data_init(void) {
+	headless_dma(_mapDataSegmentRomStart, 0x80700000, 0x100000);
+	while (headless_pi_status() & (PI_STATUS_DMA_BUSY | PI_STATUS_ERROR));
+}
+
+char *parse_map(u32 pc) {
+	u32 i;
+
+	for (i = 0; i < gMapEntrySize; i++) {
+		if (gMapEntries[i].addr >= pc) break;
+	}
+
+	if (i == gMapEntrySize - 1) {
+		return "Unknown";
+	} else {
+		return (char*) ((u32)gMapStrings + gMapEntries[i - 1].nm_offset);
+	}
+}