kernel: string: add a strcpy function

Add an implmentation of strcpy. This function is used in several places
in the kernel to copy strings between memory addresses.

Signed-off-by: Danny Holman <dholman@gymli.org>

2 files changed, 29 insertions, 4 deletions

diff --git a/kernel/init.c b/kernel/init.c
index 195ce92..86567a4 100644
--- a/kernel/init.c
+++ b/kernel/init.c
@@ -1,8 +1,25 @@
-#include <kernel/tty.h>
 #include <kernel/io.h>
+#include <kernel/mem.h>
+#include <kernel/string.h>
 #include <kernel/serial.h>
 
-void kernel_main(void) {
-        tty_init();
-        kprintf("Hello world\n");
+void jump_userspace(void);
+
+char rootfs[1024];
+
+int start_init(int argc, char* argv[]) {
+        return 0;
+}
+
+void process_cmd(char *cmdline) {
+        char *token = strtok(cmdline, " ");
+        while (token != NULL) {
+                if (strncmp(token, "root=", 5) == 0)
+                        strcpy(rootfs, &token[6]);
+        }
+}
+
+void kernel_main(char *cmdline) {
+        kprintf("Box Kernel version %s\n", VERSION);
+        serial_init();
 }
diff --git a/kernel/string.c b/kernel/string.c
index 35dc16e..fa0fd3f 100644
--- a/kernel/string.c
+++ b/kernel/string.c
@@ -31,6 +31,14 @@ void* memcpy(void* __restrict dest, const void* __restrict src, size_t n) {
         return dest;
 }
 
+char* strncpy(char* __restrict dest, const char* __restrict src, size_t n) {
+        for (int i = 0; i < n; i++) {
+                if (src[i] == '\0')
+                        break;
+                dest[i] = src[i];
+        }
+}
+
 char* strcpy(char* __restrict dest, const char* __restrict src) {
         if (strlen(src) > strlen(dest))
                 return NULL;