add: strdup

include/libasm.h

@@ -6,4 +6,5 @@
 char *ft_strcpy(char *dest, const char *src);
 size_t ft_strlen(const char *str);
 int ft_strcmp( const char *first, const char *second);
-ssize_t ft_write(int fd, const void *buf, size_t count);
+ssize_t ft_write(int fd, const void *buf, size_t count);
+char *ft_strdup(const char *s);

src/ft_strdup.asm

@@ -0,0 +1,27 @@
+extern ft_strlen
+extern malloc
+extern ft_strcpy
+
+section .text
+        global ft_strdup
+        ft_strdup:
+                call ft_strlen
+
+                mov rbx, rdi
+                mov rdi, rax
+
+                call malloc
+
+                cmp rax, 0
+                je error
+
+                mov rdi, rax
+                mov rsi, rbx
+
+                call ft_strcpy
+
+                ret
+
+        error:
+                xor rax, rax
+                ret