Shell: Fixed pushd and popd

Fixed a few issues with both `pushd` and `popd`. There was a few
typos etcetera causing it to behave errantly in certain situations.

Shell/main.cpp

@@ -175,7 +175,7 @@ static int sh_popd(int argc, char** argv)
  return 0;
  }
 
- for (int i = 0; i < argc; i++) {
+ for (int i = 1; i < argc; i++) {
  const char* arg = argv[i];
  if (!strcmp(arg, "-n")) {
  should_switch = false;
@@ -189,7 +189,6 @@ static int sh_popd(int argc, char** argv)
  }
 
  const char* real_path = canonical_path.string().characters();
- g.directory_stack.append(g.cwd.characters());
 
  struct stat st;
  int rc = stat(real_path, &st);
@@ -247,13 +246,16 @@ static int sh_pushd(int argc, char** argv)
 
  // Let's assume the user's typed in 'pushd <dir>'
  if (argc == 2) {
+ g.directory_stack.append(g.cwd.characters());
  if (argv[1][0] == '/') {
  path_builder.append(argv[1]);
  }
- else 
+ else {
  path_builder.appendf("%s/%s", g.cwd.characters(), argv[1]);
+ }
  } else if (argc == 3) {
- for (int i = 0; i < argc; i++) {
+ g.directory_stack.append(g.cwd.characters());
+ for (int i = 1; i < argc; i++) {
  const char* arg = argv[i];
 
  if (arg[0] != '-') {
@@ -276,7 +278,6 @@ static int sh_pushd(int argc, char** argv)
  }
 
  const char* real_path = canonical_path.string().characters();
- g.directory_stack.append(real_path);
 
  struct stat st;
  int rc = stat(real_path, &st);