psxbios: Add checks for strcmp & strncmp.

Yes, it's supposed to have a lot of checks like these.
Also merge some more fixes from PCSX4ALL. (upstream did not have
these as far as i know)

diff --git a/libpcsxcore/psxbios.c b/libpcsxcore/psxbios.c
index df0550e..44711b5 100644 (file)
--- a/libpcsxcore/psxbios.c
+++ b/libpcsxcore/psxbios.c
@@ -541,13 +541,35 @@ void psxBios_strncat() { // 0x16
 
 void psxBios_strcmp() { // 0x17
        char *p1 = (char *)Ra0, *p2 = (char *)Ra1;
-
+       s32 n=0;
+       if (a0 == 0 && a1 == 0)
+       {
+               v0 = 0;
+               pc0 = ra;
+               return;
+       }
+       else if (a0 == 0 && a1 != 0)
+       {
+               v0 = -1;
+               pc0 = ra;
+               return;
+       }
+       else if (a0 != 0 && a1 == 0)
+       {
+               v0 = 1;
+               pc0 = ra;
+               return;
+       }
 #ifdef PSXBIOS_LOG
        PSXBIOS_LOG("psxBios_%s: %s (%x), %s (%x)\n", biosA0n[0x17], Ra0, a0, Ra1, a1);
 #endif
 
        while (*p1 == *p2++) {
+               n++;
                if (*p1++ == '\0') {
+                       v1=n-1;
+                       a0+=n;
+                       a1+=n;
                        v0 = 0;
                        pc0 = ra;
                        return;
@@ -555,6 +577,9 @@ void psxBios_strcmp() { // 0x17
        }
 
        v0 = (*p1 - *--p2);
+       v1 = n;
+       a0+=n;
+       a1+=n;
        pc0 = ra;
 }