Fix modulo issues in vga-overlay

[netwatch.git] / lib / minilib.c

diff --git a/lib/minilib.c b/lib/minilib.c
index 232878b8478743c4a70d6574ef2785768d9e01e7..56090ed9389f9a8e1d0657649ca73438fc70203d 100644 (file)
--- a/lib/minilib.c
+++ b/lib/minilib.c
@@ -1,12 +1,66 @@
 #include "console.h"
 #include <minilib.h>
+#include <output.h>
 
-void memcpy(void *dest, void *src, int bytes)
+/* We have both _memcpy and memcpy, because gcc might be able to do better in lwip.
+ * For small things, gcc inlines its memcpy, but for large things, we call out
+ * to this memcpy.
+ */
+inline void _memcpy(void *dest, const void *src, int bytes)
 {
-       char * cdest = dest;
-       char * csrc = src;
-       while (bytes--)
+       /* I hate everyone */
+       /* Since we otherwise compile with -O0, we might as well manually speed this up a bit. */
+       
+       char *cdest = dest;
+       const char *csrc = src;
+       int *idest;
+       const int *isrc;
+       int nwords;
+       
+       /* Align to src (picked arbitrarily; might as well align to something) */
+       while (bytes && ((unsigned int)csrc & 3))
+       {
                *(cdest++) = *(csrc++);
+               bytes--;
+       }
+       
+       idest = (int *)cdest;
+       isrc = (const int *)csrc;
+       
+       nwords = bytes / 4;
+       bytes -= bytes & ~3;
+       if (nwords != 0)
+               switch(nwords % 8)      /* They see me Duff'sin'.  They hatin'. */
+                       do {
+               case  0:        nwords--; *(idest++) = *(isrc++);
+               case  7:        nwords--; *(idest++) = *(isrc++);
+               case  6:        nwords--; *(idest++) = *(isrc++);
+               case  5:        nwords--; *(idest++) = *(isrc++);
+               case  4:        nwords--; *(idest++) = *(isrc++);
+               case  3:        nwords--; *(idest++) = *(isrc++);
+               case  2:        nwords--; *(idest++) = *(isrc++);
+               case  1:        nwords--; *(idest++) = *(isrc++);
+                       } while (nwords);
+       
+       cdest = (char *)idest;
+       csrc = (const char *)isrc;
+       while (bytes)   /* Clean up the remainder */
+       {
+               *(cdest++) = *(csrc++);
+               bytes--;
+       }
+}
+
+void memcpy(void *dest, const void *src, int bytes)
+{
+       _memcpy(dest, src, bytes);
+}
+
+void memset(void *dest, int data, int bytes)
+{
+       unsigned char *cdest = dest;
+       while (bytes--)
+               *(cdest++) = (unsigned char)data;
 }
 
 void memmove(void *dest, void *src, int bytes)
@@ -21,8 +75,7 @@ void memmove(void *dest, void *src, int bytes)
                while (bytes--)
                        *(--cdest) = *(--csrc);
        } else
-               while (bytes--)
-                       *(cdest++) = *(csrc++);
+               memcpy(dest, src, bytes);
 }
 
 int memcmp (const char *a2, const char *a1, int bytes) {
@@ -43,7 +96,17 @@ int strcmp (const char *a2, const char *a1) {
        }
 }
 
-int strlen(char *c)
+int strncmp (const char *a2, const char *a1, int n) {
+       while (n--) {
+               if (*a2 != *a1) return 1;
+               if (*a2 == 0) return 0;
+               a1++;
+               a2++;
+       }
+       return 0;
+}
+
+int strlen(const char *c)
 {
        int l = 0;
        while (*(c++))
@@ -58,7 +121,16 @@ void strcpy(char *a2, const char *a1)
        } while (*(a1++));
 }
 
-void puts(char *c)
+void strcat(char *dest, char *src)
+{
+       while (*dest)
+               dest++;
+       while (*src)
+               *(dest++) = *(src++);
+       *(dest++) = *(src++);
+}
+
+void puts(const char *c)
 {
        putbytes(c, strlen(c));
 }
@@ -82,4 +154,15 @@ void puthex(unsigned long l)
        puts(d);
 }
 
+unsigned short htons(unsigned short in)
+{
+       return (in >> 8) | (in << 8);
+}
 
+unsigned int htonl(unsigned int in)
+{
+       return ((in & 0xff) << 24) |
+              ((in & 0xff00) << 8) |
+              ((in & 0xff0000UL) >> 8) |
+              ((in & 0xff000000UL) >> 24);
+}