bash "test" -nt and -ot operators mishandle nonpositive timestamps

[Paul Eggert]

Configuration Information [Automatically generated, do not change]:
Machine: sparc
OS: solaris2.8
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='sparc' 
-DCONF_OSTYPE='solaris2.8' -DCONF_MACHTYPE='sparc-sun-solaris2.8' 
-DCONF_VENDOR='sun' -DSHELL  -DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib -g 
-O2 -Wall -W -Wno-sign-compare -Wpointer-arith -Wstrict-prototypes 
-Wmissing-prototypes -Wmissing-noreturn -Wmissing-format-attribute
uname output: SunOS sic.twinsun.com 5.8 Generic_108528-13 sun4u sparc 
SUNW,UltraSPARC-IIi-Engine
Machine Type: sparc-sun-solaris2.8

Bash Version: 2.05a
Patch Level: 0
Release Status: release

Description:
        The "-ot" and "-nt" operators of the "test" command mishandle
        the case where one file has a nonpositive timestamp and the
        other file does not exist.  Files that do not exist should
        always be considered to be older than files that do exist.

Repeat-By:
        $ touch -m -t 196001010000 /var/tmp/foo
        $ ls -l /var/tmp/foo
        -rw-rw-r--   1 eggert   eggert         0 Jan  1  1960 /var/tmp/foo
        $ test /no/such/file -nt /var/tmp/foo && echo bug
        bug

Fix:

2002-02-26  Paul Eggert  <eggert@twinsun.com>

        * test.c (filecomp): Fix bug when one file has a nonpositive
        timestamp and the other file does not exist.

===================================================================
RCS file: test.c,v
retrieving revision 2.5.1.4.0.1
retrieving revision 2.5.1.4.0.2
diff -pu -r2.5.1.4.0.1 -r2.5.1.4.0.2
--- test.c      2001/11/19 06:25:18     2.5.1.4.0.1
+++ test.c      2002/02/26 23:42:34     2.5.1.4.0.2
@@ -395,25 +395,24 @@ filecomp (s, t, op)
      char *s, *t;
      int op;
 {
+  int r1, r2;
   struct stat st1, st2;
 
-  if (test_stat (s, &st1) < 0)
+  if ((r1 = test_stat (s, &st1)) < 0)
     {
-      st1.st_mtime = 0;
       if (op == EF)
        return (FALSE);
     }
-  if (test_stat (t, &st2) < 0)
+  if ((r2 = test_stat (t, &st2)) < 0)
     {
-      st2.st_mtime = 0;
       if (op == EF)
        return (FALSE);
     }
   
   switch (op)
     {
-    case OT: return (st1.st_mtime < st2.st_mtime);
-    case NT: return (st1.st_mtime > st2.st_mtime);
+    case OT: return (r1 < r2 || (r2 == 0 && st1.st_mtime < st2.st_mtime));
+    case NT: return (r1 > r2 || (r1 == 0 && st1.st_mtime > st2.st_mtime));
     case EF: return ((st1.st_dev == st2.st_dev) && (st1.st_ino == st2.st_ino));
     }
   return (FALSE);