Fix directory scanner to correctly ignore files without d_type

torvalds · spearce · commit 07134421fc57 · 2007-10-21T01:44:40.000-04:00
On Fri, 19 Oct 2007, Todd T. Fries wrote:
&gt; If DT_UNKNOWN exists, then we have to do a stat() of some form to
&gt; find out the right type.

That happened in the case of a pathname that was ignored, and we did
not ask for "dir-&gt;show_ignored". That test used to be *together*
with the "DTYPE(de) != DT_DIR", but splitting the two tests up
means that we can do that (common) test before we even bother to
calculate the real dtype.

Of course, that optimization only matters for systems that don't
have, or don't fill in DTYPE properly.

I also clarified the real relationship between "exclude" and
"dir-&gt;show_ignored". It used to do

	if (exclude != dir-&gt;show_ignored) {
		..

which wasn't exactly obvious, because it triggers for two different
cases:

 - the path is marked excluded, but we are not interested in ignored
   files: ignore it

 - the path is *not* excluded, but we *are* interested in ignored
   files: ignore it unless it's a directory, in which case we might
   have ignored files inside the directory and need to recurse
   into it).

so this splits them into those two cases, since the first case
doesn't even care about the type.

I also made a the DT_UNKNOWN case a separate helper function,
and added some commentary to the cases.

		Linus

Signed-off-by: Shawn O. Pearce &lt;spearce@spearce.org&gt;
diff --git a/dir.c b/dir.c
@@ -443,6 +443,24 @@ static int in_pathspec(const char *path, int len, const struct path_simplify *si
 	return 0;
 }
 
+static int get_dtype(struct dirent *de, const char *path)
+{
+	int dtype = DTYPE(de);
+	struct stat st;
+
+	if (dtype != DT_UNKNOWN)
+		return dtype;
+	if (lstat(path, &st))
+		return dtype;
+	if (S_ISREG(st.st_mode))
+		return DT_REG;
+	if (S_ISDIR(st.st_mode))
+		return DT_DIR;
+	if (S_ISLNK(st.st_mode))
+		return DT_LNK;
+	return dtype;
+}
+
 /*
  * Read a directory tree. We currently ignore anything but
  * directories, regular files and symlinks. That's because git
@@ -466,7 +484,7 @@ static int read_directory_recursive(struct dir_struct *dir, const char *path, co
 		exclude_stk = push_exclude_per_directory(dir, base, baselen);
 
 		while ((de = readdir(fdir)) != NULL) {
-			int len;
+			int len, dtype;
 			int exclude;
 
 			if ((de->d_name[0] == '.') &&
@@ -486,24 +504,30 @@ static int read_directory_recursive(struct dir_struct *dir, const char *path, co
 			if (exclude && dir->collect_ignored
 			    && in_pathspec(fullname, baselen + len, simplify))
 				dir_add_ignored(dir, fullname, baselen + len);
-			if (exclude != dir->show_ignored) {
-				if (!dir->show_ignored || DTYPE(de) != DT_DIR) {
+
+			/*
+			 * Excluded? If we don't explicitly want to show
+			 * ignored files, ignore it
+			 */
+			if (exclude && !dir->show_ignored)
+				continue;
+
+			dtype = get_dtype(de, fullname);
+
+			/*
+			 * Do we want to see just the ignored files?
+			 * We still need to recurse into directories,
+			 * even if we don't ignore them, since the
+			 * directory may contain files that we do..
+			 */
+			if (!exclude && dir->show_ignored) {
+				if (dtype != DT_DIR)
 					continue;
-				}
 			}
 
-			switch (DTYPE(de)) {
-			struct stat st;
+			switch (dtype) {
 			default:
 				continue;
-			case DT_UNKNOWN:
-				if (lstat(fullname, &st))
-					continue;
-				if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode))
-					break;
-				if (!S_ISDIR(st.st_mode))
-					continue;
-				/* fallthrough */
 			case DT_DIR:
 				memcpy(fullname + baselen + len, "/", 2);
 				len++;
