discover: Add support for checking directories in parser API

This change adds a function to the parser API:

  int parser_check_dir(struct discover_context *ctx,
  		struct discover_device *dev, const char *dirname)

- which allows parsers to check for the presence of a directory (path of
'dirname') on the device ('dev'). We use this in the GRUB2 parser to
implement the `test -d` check.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/discover/parser.c b/discover/parser.c
index 21b48de..74b2559 100644
--- a/discover/parser.c
+++ b/discover/parser.c
@@ -49,6 +49,25 @@ int parser_request_file(struct discover_context *ctx,
 	return rc;
 }
 
+int parser_check_dir(struct discover_context *ctx,
+		struct discover_device *dev, const char *dirname)
+{
+	struct stat statbuf;
+	char *path;
+	int rc;
+
+	if (!dev->mount_path)
+		return -1;
+
+	path = local_path(ctx, dev, dirname);
+
+	rc = stat(path, &statbuf);
+	if (!rc)
+		return -1;
+
+	return S_ISDIR(statbuf.st_mode) ? 0 : -1;
+}
+
 int parser_replace_file(struct discover_context *ctx,
 		struct discover_device *dev, const char *filename,
 		char *buf, int len)