[gnome-color-manager] Ensure EDID strings are printable, and ignore totally junk strings

[Richard Hughes <rhughes src gnome org>]

commit 20267bc0f0c2838fe9108a6537acca22f01d7f4a
Author: Richard Hughes <richard hughsie com>
Date:   Thu Sep 30 18:57:44 2010 +0100

    Ensure EDID strings are printable, and ignore totally junk strings

 libcolor-glib/gcm-edid.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)
---
diff --git a/libcolor-glib/gcm-edid.c b/libcolor-glib/gcm-edid.c
index 819d51a..654fb75 100644
--- a/libcolor-glib/gcm-edid.c
+++ b/libcolor-glib/gcm-edid.c
@@ -336,6 +336,8 @@ static gchar *
 gcm_edid_parse_string (const guint8 *data)
 {
 	gchar *text;
+	guint i;
+	guint replaced = 0;
 
 	/* copy 12 bytes */
 	text = g_strndup ((const gchar *) data, 12);
@@ -350,7 +352,24 @@ gcm_edid_parse_string (const guint8 *data)
 	if (text[0] == '\0') {
 		g_free (text);
 		text = NULL;
+		goto out;
+	}
+
+	/* ensure string is printable */
+	for (i=0;i<12;i++) {
+		if (!g_ascii_isprint (text[i])) {
+			text[i] = '-';
+			replaced++;
+		}
 	}
+
+	/* if the string is junk, ignore the string */
+	if (replaced > 4) {
+		g_free (text);
+		text = NULL;
+		goto out;
+	}
+out:
 	return text;
 }