[PATCH v3 2/2] discover/syslinux-parser: filter out duplicate conf files

[Brett Grandbois]

in case insensitive filesystems like vfat the duplicate conf file list
will create duplicate boot options.  to filter that out strore the
struct stat of each parsed conf file and compare inodes

Signed-off-by: Brett Grandbois <brett.grandbois at opengear.com>
---
 discover/syslinux-parser.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/discover/syslinux-parser.c b/discover/syslinux-parser.c
index b127494..be7b94a 100644
--- a/discover/syslinux-parser.c
+++ b/discover/syslinux-parser.c
@@ -36,6 +36,11 @@ struct syslinux_options {
 	char *cfg_dir;
 };
 
+struct conf_file_stat {
+	char *name;
+	struct stat stat;
+	struct list_item list;
+};
 
 static const char *const syslinux_conf_files[] = {
 	"/boot/syslinux/syslinux.cfg",
@@ -416,9 +421,12 @@ fail:
 
 static int syslinux_parse(struct discover_context *dc)
 {
+	struct conf_file_stat *confcmp, *confdat;
+	struct list processed_conf_files;
 	struct syslinux_options *state;
 	const char * const *filename;
 	struct conf_context *conf;
+	struct stat statbuf;
 	char *cfg_dir;
 	int len, rc;
 	char *buf;
@@ -441,6 +449,8 @@ static int syslinux_parse(struct discover_context *dc)
 	conf->parser_info = state = talloc_zero(conf, struct syslinux_options);
 	list_init(&state->processed_options);
 
+	list_init(&processed_conf_files);
+
 	/*
 	 * set the global defaults
 	 * by spec 'default' defaults to 'linux' and
@@ -453,10 +463,37 @@ static int syslinux_parse(struct discover_context *dc)
 	conf_set_global_option(conf, "append", "");
 
 	for (filename = syslinux_conf_files; *filename; filename++) {
+		/*
+		 * guard against duplicate entries in case-insensitive
+		 * filesystems, mainly vfat boot partitions
+		 */
+		rc = parser_stat_path(dc, dc->device, *filename, &statbuf);
+		if (rc)
+			continue;
+
+		rc = 0;
+
+		list_for_each_entry(&processed_conf_files, confcmp, list) {
+			if (confcmp->stat.st_ino == statbuf.st_ino) {
+				pb_log("conf file %s is a path duplicate of %s..skipping\n",
+				       *filename, confcmp->name);
+				rc = 1;
+				break;
+			}
+		}
+
+		if (rc)
+			continue;
+
 		rc = parser_request_file(dc, dc->device, *filename, &buf, &len);
 		if (rc)
 			continue;
 
+		confdat = talloc_zero(conf, struct conf_file_stat);
+		confdat->stat = statbuf;
+		confdat->name = talloc_strdup(confdat, *filename);
+		list_add(&processed_conf_files, &confdat->list);
+
 		/*
 		 * save location of root config file for possible
 		 * INCLUDE directives later
-- 
2.7.4