undo: fix hanging on fake transaction ids.

Reported-by: Justin Sherrill <justin@shiningsilence.com>

diff --git a/usr.bin/undo/undo.c b/usr.bin/undo/undo.c
index 7803f10..cf78daa 100644 (file)
--- a/usr.bin/undo/undo.c
+++ b/usr.bin/undo/undo.c
@@ -246,6 +246,7 @@ doiterate(const char *filename, const char *outFileName,
        struct undo_hist_entry *tse1;
        struct undo_hist_entry *tse2;
        struct hammer_ioc_hist_entry tid_max;
+       struct stat sb;
        char *path = NULL;
        int i;
        int fd;
@@ -264,6 +265,11 @@ doiterate(const char *filename, const char *outFileName,
        collect_dir_history(filename, &error, &dir_tree);
        RB_FOREACH(tse1, undo_hist_entry_rb_tree, &dir_tree) {
                asprintf(&path, "%s@@0x%016jx", filename, (uintmax_t)tse1->tse.tid);
+               stat(path, &sb);
+               if (sb.st_mode & S_IFIFO) {
+                       fprintf(stderr, "Warning: fake transaction id 0x%016jx\n", (uintmax_t)tse1->tse.tid);
+                       continue;
+               }
                if ((fd = open(path, O_RDONLY)) > 0) {
                        collect_history(fd, &error, &tse_tree);
                        close(fd);