Add basic ls

src/kernel/kernel.c

@@ -56,7 +56,7 @@ void kernel_main() {
   kernel->stdin = keyboard_init();
   kernel->stdout = vga_init();
 
-  fs_node_t *bin = fs_open_by(kernel->root, "terminal");
+  fs_node_t *bin = path_open_file(kernel->root, kernel->cwd, "bin/terminal");
 
   ASSERT(bin, "kernel: terminal not found");
 

src/kernel/syscall.asm

@@ -28,6 +28,7 @@ syscall_entry:
     push r14
     push r15
 
+    mov r8, r10     ; arg4
     mov rcx, rdx    ; arg3
     mov rdx, rsi    ; arg2
     mov rsi, rdi    ; arg1

src/kernel/syscall.c

@@ -145,11 +145,36 @@ static uint64_t spawn(const char *path, uint64_t argc, const char **argv) {
   return 0;
 }
 
+static uint64_t readdir(const char *path, uint64_t index, uint64_t max, char *to) {
+  fs_node_t *dir = path_open_directory(current_process->root, current_process->cwd, path);
+  if (!dir) {
+    return (uint64_t)-1;
+  }
+  fs_node_t *item = fs_open_at(dir, index);
+  if (!item) {
+    if (dir != current_process->root) {
+      fs_close(dir);
+    }
+    return 0;
+  }
+  uint64_t length = string_length(item->name);
+  uint64_t size = length > max - 1 ? max - 1 : length;
+  memory_copy(item->name, size, to);
+  to[size] = '\0';
+
+  fs_close(item);
+  if (dir != current_process->root) {
+    fs_close(dir);
+  }
+
+  return size;
+}
+
 static void exit() {
   process_switch_to(&current_process->kernel_rsp, current_process->parent->kernel_rsp, VIRT_TO_PHYS(current_process->parent->pml4));
 }
 
-uint64_t syscall_dispatch(uint64_t func, uint64_t arg1, uint64_t arg2, uint64_t arg3) {
+uint64_t syscall_dispatch(uint64_t func, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4) {
   switch (func) {
   case SYSCALL_READ:
     return read(arg1, arg2, (char *)arg3);
@@ -161,6 +186,8 @@ uint64_t syscall_dispatch(uint64_t func, uint64_t arg1, uint64_t arg2, uint64_t
     return chdir((const char *)arg1);
   case SYSCALL_SPAWN:
     return spawn((const char *)arg1, arg2, (const char **)arg3);
+  case SYSCALL_READDIR:
+    return readdir((const char *)arg1, arg2, arg3, (char *)arg4);
   case SYSCALL_EXIT:
     exit();
     return 0;

src/kernel/syscall.h

@@ -7,8 +7,9 @@
 #define SYSCALL_GETCWD 2
 #define SYSCALL_CHDIR 3
 #define SYSCALL_SPAWN 4
+#define SYSCALL_READDIR 5
 #define SYSCALL_EXIT 60
 
 void syscall_init();
 
-uint64_t syscall_dispatch(uint64_t func, uint64_t arg1, uint64_t arg2, uint64_t arg3);
+uint64_t syscall_dispatch(uint64_t func, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4);