working userland with some invoke syscalls

1 files changed, 27 insertions, 0 deletions

diff --git a/lib/mem.c b/lib/mem.c
new file mode 100644
index 0000000..2ce67f3
--- /dev/null
+++ b/lib/mem.c
@@ -0,0 +1,27 @@
+#include "string.h"
+
+void*
+memset(void *dest, char c, size_t n)
+{
+    char *a = dest;
+    for(size_t i = 0; i < n; i++) a[i] = c;
+    return dest;
+}
+
+void*
+memcpy(void *dest, const void *src, size_t n)
+{
+    char *a = dest;
+    const char *b = src;
+    for(size_t i = 0; i < n; i++) a[i] = b[i];
+    return dest;
+}
+
+void*
+memmove(void *dest, const void *src, size_t n)
+{
+    char buffer[n];
+    memcpy(buffer, src, n);
+    memcpy(dest, buffer, n);
+    return dest;
+}