Add basic ls

src/user/app/echo/echo.c

@@ -1,7 +1,7 @@
 #include "src/lib/string.h"
 #include "src/user/syscall.h"
 
-int main(uint64_t argc, const char **argv) {
+uint64_t main(uint64_t argc, const char **argv) {
   for (uint64_t i = 1; i < argc; i++) {
     if (i > 1) {
       write(1, " ", 1);

src/user/app/ls/ls.c

@@ -0,0 +1,43 @@
+#include "src/lib/string.h"
+#include "src/user/syscall.h"
+
+#define WRITE_S(s) write(1, s, sizeof(s) - 1);
+#define WRITE_D(s) write(1, s, string_length(s));
+
+uint64_t ls(const char *path) {
+  uint64_t i = 0;
+  while (1) {
+    char out[100];
+    uint64_t s = readdir(path, i, 100, out);
+    if (!s) {
+      return 0;
+    }
+    if (s == (uint64_t)-1) {
+      WRITE_S("ls: path does not exist\n");
+      return (uint64_t)-1;
+    }
+    WRITE_D(out);
+    WRITE_S("\n");
+    i++;
+  }
+}
+
+uint64_t main(uint64_t argc, const char **argv) {
+  if (argc == 1) {
+    return ls(".");
+  }
+
+  uint64_t code = 0;
+  for (uint64_t i = 1; i < argc; i++) {
+    if (argc > 2) {
+      WRITE_S("\n");
+      WRITE_D(argv[i]);
+      WRITE_S(":\n");
+    }
+    if (ls(argv[i]) == (uint64_t)-1) {
+      code = (uint64_t)-1;
+    }
+  }
+
+  return code;
+}

src/user/app/terminal/terminal.c

@@ -6,6 +6,8 @@
 static void help(uint8_t argc, char **argv);
 static void cd(uint8_t argc, char **argv);
 
+#define PATH "/bin/"
+
 #define WRITE_S(s) write(1, s, sizeof(s) - 1);
 #define WRITE_D(s) write(1, s, string_length(s));
 
@@ -117,9 +119,14 @@ static void on_enter_pressed() {
     }
   }
   if (i == sizeof(builtins) / sizeof(app_entry_t)) {
-    if (spawn(argv[0], argc, (const char **)argv) == (uint64_t)-1){
+    uint64_t size = sizeof(PATH) + string_length(argv[0]) + 1;
+    char *path = memory_allocate(size);
+    memory_copy(PATH, sizeof(PATH), path);
+    memory_copy(argv[0], size - sizeof(PATH), path + sizeof(PATH) - 1);
+    if (spawn(path, argc, (const char **)argv) == (uint64_t)-1) {
       WRITE_S("terminal: program not found\n");
     }
+    memory_free(path);
   }
   prompt_length = prompt_offset = 0;
   print_prompt();
@@ -258,7 +265,7 @@ static void on_char_received(char c) {
   }
 }
 
-int main() {
+uint64_t main() {
   memory_set('\b', PROMPT_LENGTH, (char *)bs);
   memory_set(' ', PROMPT_LENGTH, (char *)ws);