libc: Add execl()

libc/include/unistd.h

@@ -31,6 +31,9 @@ extern "C"
     /* Replace the current process with another one. On success, does not return. */
     int execv(const char* path, char* const* argv);
 
+    /* Replace the current process with another one. On success, does not return. */
+    int execl(const char* path, const char* arg, ...);
+
     int execve(const char*, char* const*, char* const*);
     int execvp(const char*, char* const*);
 

libc/src/unistd.cpp

@@ -1,3 +1,5 @@
+#include <luna/Vector.h>
+
 #include <bits/errno-return.h>
 #include <fcntl.h>
 #include <stdarg.h>
@@ -31,6 +33,26 @@ extern "C"
         __errno_return(rc, int);
     }
 
+    int execl(const char* path, const char* arg, ...)
+    {
+        va_list ap;
+        va_start(ap, arg);
+
+        Vector<char*> args;
+        if (args.try_append(const_cast<char*>(arg)).has_error()) return -1;
+
+        while (true)
+        {
+            char* str = va_arg(ap, char*);
+            if (args.try_append(str).has_error()) return -1;
+            if (!str) break;
+        }
+
+        va_end(ap);
+
+        return execv(path, args.data());
+    }
+
     long syscall(long num, ...)
     {
         va_list ap;