Re: [Bug-tar] Error "Cannot allocate memory" incorrectly reported in some cases.

[Paul Eggert]

"Sergey Poznyakoff" <address@hidden> writes:

> --- lib/savedir.c     19 Sep 2005 17:28:15 -0000      1.26
> +++ lib/savedir.c     28 Oct 2005 12:39:06 -0000
> @@ -104,6 +104,7 @@ savedir (const char *dir)
>             while (allocated <= used + entry_size);
>  
>             name_space = xrealloc (name_space, allocated);
> +              errno = 0;
>           }
>         memcpy (name_space + used, entry, entry_size);
>         used += entry_size;

Thanks for the diagnosis, but the fix isn't quite right in general,
since the C standard says memcpy can set errno as well.

I installed this patch instead, both in gnulib and coreutils.

2005-10-28  Paul Eggert  <address@hidden>

        * lib/savedir.c (savedir): Don't assume that xrealloc etc. leave
        errno alone.  Problem reported by Frederic Jolliton.

--- lib/savedir.c       19 Sep 2005 17:28:15 -0000      1.26
+++ lib/savedir.c       28 Oct 2005 23:01:41 -0000
@@ -70,7 +70,6 @@ char *
 savedir (const char *dir)
 {
   DIR *dirp;
-  struct dirent *dp;
   char *name_space;
   size_t allocated = NAME_SIZE_DEFAULT;
   size_t used = 0;
@@ -82,12 +81,19 @@ savedir (const char *dir)
 
   name_space = xmalloc (allocated);
 
-  errno = 0;
-  while ((dp = readdir (dirp)) != NULL)
+  for (;;)
     {
+      struct dirent const *dp;
+      char const *entry;
+
+      errno = 0;
+      dp = readdir (dirp);
+      if (! dp)
+       break;
+
       /* Skip "", ".", and "..".  "" is returned by at least one buggy
          implementation: Solaris 2.4 readdir on NFS file systems.  */
-      char const *entry = dp->d_name;
+      entry = dp->d_name;
       if (entry[entry[0] != '.' ? 0 : entry[1] != '.' ? 1 : 2] != '\0')
        {
          size_t entry_size = strlen (entry) + 1;