added working paging small kernel

Tests/isa/Cprograms/string.c

@@ -0,0 +1,114 @@
+#include <string.h>
+#include <stdint.h>
+#include <ctype.h>
+
+void* memcpy(void* dest, const void* src, size_t len)
+{
+  if ((((uintptr_t)dest | (uintptr_t)src | len) & (sizeof(uintptr_t)-1)) == 0) {
+    const uintptr_t* s = src;
+    uintptr_t *d = dest;
+    while (d < (uintptr_t*)(dest + len))
+      *d++ = *s++;
+  } else {
+    const char* s = src;
+    char *d = dest;
+    while (d < (char*)(dest + len))
+      *d++ = *s++;
+  }
+  return dest;
+}
+
+void* memset(void* dest, int byte, size_t len)
+{
+  if ((((uintptr_t)dest | len) & (sizeof(uintptr_t)-1)) == 0) {
+    uintptr_t word = byte & 0xFF;
+    word |= word << 8;
+    word |= word << 16;
+    word |= word << 16 << 16;
+
+    uintptr_t *d = dest;
+    while (d < (uintptr_t*)(dest + len))
+      *d++ = word;
+  } else {
+    char *d = dest;
+    while (d < (char*)(dest + len))
+      *d++ = byte;
+  }
+  return dest;
+}
+
+size_t strlen(const char *s)
+{
+  const char *p = s;
+  while (*p)
+    p++;
+  return p - s;
+}
+
+int strcmp(const char* s1, const char* s2)
+{
+  unsigned char c1, c2;
+
+  do {
+    c1 = *s1++;
+    c2 = *s2++;
+  } while (c1 != 0 && c1 == c2);
+
+  return c1 - c2;
+}
+
+int memcmp(const void* s1, const void* s2, size_t n)
+{
+  if ((((uintptr_t)s1 | (uintptr_t)s2) & (sizeof(uintptr_t)-1)) == 0) {
+    const uintptr_t* u1 = s1;
+    const uintptr_t* u2 = s2;
+    const uintptr_t* end = u1 + (n / sizeof(uintptr_t));
+    while (u1 < end) {
+      if (*u1 != *u2)
+        break;
+      u1++;
+      u2++;
+    }
+    n -= (const void*)u1 - s1;
+    s1 = u1;
+    s2 = u2;
+  }
+
+  while (n--) {
+    unsigned char c1 = *(const unsigned char*)s1++;
+    unsigned char c2 = *(const unsigned char*)s2++;
+    if (c1 != c2)
+      return c1 - c2;
+  }
+
+  return 0;
+}
+
+char* strcpy(char* dest, const char* src)
+{
+  char* d = dest;
+  while ((*d++ = *src++))
+    ;
+  return dest;
+}
+
+long atol(const char* str)
+{
+  long res = 0;
+  int sign = 0;
+
+  while (*str == ' ')
+    str++;
+
+  if (*str == '-' || *str == '+') {
+    sign = *str == '-';
+    str++;
+  }
+
+  while (*str) {
+    res *= 10;
+    res += *str++ - '0';
+  }
+
+  return sign ? -res : res;
+}