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authorRandom <28494085+Random06457@users.noreply.github.com>2020-10-03 17:22:44 +0200
committerGitHub <noreply@github.com>2020-10-03 11:22:44 -0400
commit174af7384d1cfcbf15da02d9069bf02bdc433c20 (patch)
treee4fb18346f71047c123ec4d34a80ae7e4d8ab9ea /src/libultra_code_O2/__osContAddressCrc.c
parent6136ee6debd570a63fc695a6f4664553303f2324 (diff)
libultra cleanup (#215)
* cleanup libultra * fixes - use quotes instead of <> for includes - add macros for zelda specific thread priorities - fix Makefile - properly format the remaining pfs structs * fix button macros + add CHECK_BTN_ANY/CHECK_BTN_ALL * remove ULTRA_ABS * fix includes * update z_player.c/z_lib.c + run format.sh * merge upstream/master * fix include in En_Goroiwa * fix includes
Diffstat (limited to 'src/libultra_code_O2/__osContAddressCrc.c')
-rw-r--r--src/libultra_code_O2/__osContAddressCrc.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/src/libultra_code_O2/__osContAddressCrc.c b/src/libultra_code_O2/__osContAddressCrc.c
new file mode 100644
index 000000000..9b0c779ec
--- /dev/null
+++ b/src/libultra_code_O2/__osContAddressCrc.c
@@ -0,0 +1,65 @@
+#include "global.h"
+
+// Valid addr up to 0x7FF
+// It's the address of a block of 0x20 bytes in the mempak
+// So that means the whole mempak has a 16-bit address space
+u8 __osContAddressCrc(u16 addr) {
+ u32 addr32 = addr;
+ u32 ret = 0;
+ u32 bit;
+ s32 i;
+
+ for (bit = 0x400; bit; bit >>= 1) {
+ ret <<= 1;
+ if (addr32 & bit) {
+ if (ret & 0x20) {
+ ret ^= 0x14;
+ } else {
+ ++ret;
+ }
+ } else {
+ if (ret & 0x20) {
+ ret ^= 0x15;
+ }
+ }
+ }
+ for (i = 0; i < 5; ++i) {
+ ret <<= 1;
+ if (ret & 0x20) {
+ ret ^= 0x15;
+ }
+ }
+ return ret & 0x1f;
+}
+
+u8 __osContDataCrc(u8* data) {
+ s32 ret;
+ u32 bit;
+ u32 byte;
+
+ ret = 0;
+ for (byte = 0x20; byte; --byte, ++data) {
+ for (bit = 0x80; bit; bit >>= 1) {
+ ret <<= 1;
+ if ((*data & bit) != 0) {
+ if ((ret & 0x100) != 0) {
+ ret ^= 0x84;
+ } else {
+ ++ret;
+ }
+ } else {
+ if (ret & 0x100) {
+ ret ^= 0x85;
+ }
+ }
+ }
+ }
+ do {
+ ret <<= 1;
+ if (ret & 0x100) {
+ ret ^= 0x85;
+ }
+ ++byte;
+ } while (byte < 8U);
+ return ret;
+}