journalctl: tighten rules on parsing namespace journal dir suffixes

The dot must follow the machine ID immediately, let's check for that.
Also, I think it's generally better to parse the machine ID and then
comparing it, instead of comparing the string representation. That's
more in line how we usually do it, as we parse 128bit IDs generally
case-insensitively.

diff --git a/src/journal/journalctl-misc.c b/src/journal/journalctl-misc.c
index 9d878e8e0564b357ba46a1c9f919e3facad4540f..47eb72575ab92e86d9bbeab1a174d8a848535f82 100644 (file)
--- a/src/journal/journalctl-misc.c
+++ b/src/journal/journalctl-misc.c
@@ -211,7 +211,6 @@ int action_list_field_names(void) {
 int action_list_namespaces(void) {
         _cleanup_(table_unrefp) Table *table = NULL;
         sd_id128_t machine;
-        char machine_id[SD_ID128_STRING_MAX];
         int r;
 
         assert(arg_action == ACTION_LIST_NAMESPACES);
@@ -220,8 +219,6 @@ int action_list_namespaces(void) {
         if (r < 0)
                 return log_error_errno(r, "Failed to get machine ID: %m");
 
-        sd_id128_to_string(machine, machine_id);
-
         table = table_new("namespace");
         if (!table)
                 return log_oom();
@@ -243,19 +240,29 @@ int action_list_namespaces(void) {
                 }
 
                 FOREACH_DIRENT(de, dirp, return log_error_errno(errno, "Failed to iterate through %s: %m", path)) {
-                        char *dot;
 
-                        if (!startswith(de->d_name, machine_id))
+                        const char *e = strchr(de->d_name, '.');
+                        if (!e)
+                                continue;
+
+                        _cleanup_free_ char *ids = strndup(de->d_name, e - de->d_name);
+                        if (!ids)
+                                return log_oom();
+
+                        sd_id128_t id;
+                        r = sd_id128_from_string(ids, &id);
+                        if (r < 0)
                                 continue;
 
-                        dot = strchr(de->d_name, '.');
-                        if (!dot)
+                        if (!sd_id128_equal(machine, id))
                                 continue;
 
-                        if (!log_namespace_name_valid(dot + 1))
+                        e++;
+
+                        if (!log_namespace_name_valid(e))
                                 continue;
 
-                        r = table_add_cell(table, NULL, TABLE_STRING, dot + 1);
+                        r = table_add_cell(table, NULL, TABLE_STRING, e);
                         if (r < 0)
                                 return table_log_add_error(r);
                 }