move source files to own subdirectory

[rsbs2] / src / rsb-crc.c

diff --git a/src/rsb-crc.c b/src/rsb-crc.c
new file mode 100644 (file)
index 0000000..6a2bf99
--- /dev/null
+++ b/src/rsb-crc.c
@@ -0,0 +1,54 @@
+#include <stdio.h>
+
+#define POLY 0x04c11db7
+
+unsigned int rsb_crc(unsigned int r11_crc, unsigned char *r10_buf, unsigned int r14_len) {
+       unsigned int r6_pos = 0;
+       unsigned int r3_data;
+       int r5_bit;
+
+       while (r6_pos < r14_len) {
+               r3_data = (*(r6_pos+r10_buf)) << 24;
+               r11_crc = r11_crc ^ r3_data;
+
+               r5_bit = 8;
+               
+               do {
+                       r3_data = r11_crc & 0x80000000;
+
+                       if (r3_data != 0) {
+                               r3_data = r11_crc << 1;
+                               r11_crc = r3_data ^ POLY;
+                       } else {
+                               r11_crc = r11_crc << 1;
+                       }
+                       r5_bit--;
+               } while (r5_bit);
+
+               r6_pos++;
+       }
+
+       return r11_crc;
+}
+
+unsigned int rsb_crc2(unsigned char *r0_buf, unsigned int r1_buflen, unsigned int r2_magic, unsigned int *crc_out) {
+       unsigned int r4_len;
+       unsigned int file_crc;
+
+       r4_len = *(unsigned int*)(r0_buf + 0x20);
+
+       if (*((unsigned int*)(r0_buf + 0x24)) != r2_magic)
+               return 2; /* MAGIC does not match */
+       
+       if (r1_buflen < r4_len)
+               return 3; /* image to small */
+       
+       *crc_out = ~rsb_crc(~0x0, r0_buf, r4_len);
+
+       file_crc = *((unsigned int*)(r0_buf + r4_len));
+
+       if (file_crc != *crc_out)
+               return 4;
+
+       return 0;
+}