tar: live within system-supplied limits on file descriptors

[chaz/tar] / src / incremen.c

diff --git a/src/incremen.c b/src/incremen.c
index afd19af66ae7e67db457669f3c1e4d1579d345ad..c6d4f4c5849a2ecdb5e9633a36e718c95e195f93 100644 (file)
--- a/src/incremen.c
+++ b/src/incremen.c
@@ -426,7 +426,6 @@ procdir (const char *name_buffer, struct tar_stat_info *st,
 {
   struct directory *directory;
   struct stat *stat_data = &st->stat;
-  int fd = st->fd;
   dev_t device = st->parent ? st->parent->stat.st_dev : 0;
   bool nfs = NFS_FILE_STAT (*stat_data);
 
@@ -566,7 +565,7 @@ procdir (const char *name_buffer, struct tar_stat_info *st,
     {
       const char *tag_file_name;
 
-      switch (check_exclusion_tags (fd, &tag_file_name))
+      switch (check_exclusion_tags (st, &tag_file_name))
        {
        case exclusion_tag_all:
          /* This warning can be duplicated by code in dump_file0, but only
@@ -680,8 +679,7 @@ struct directory *
 scan_directory (struct tar_stat_info *st)
 {
   char const *dir = st->orig_file_name;
-  int fd = st->fd;
-  char *dirp = 0;
+  char *dirp = get_directory_entries (st);
   dev_t device = st->stat.st_dev;
   bool cmdline = ! st->parent;
   namebuf_t nbuf;
@@ -689,18 +687,6 @@ scan_directory (struct tar_stat_info *st)
   struct directory *directory;
   char ch;
 
-  int dupfd = dup (fd);
-  if (0 <= dupfd)
-    {
-      dirp = fdsavedir (dupfd);
-      if (! dirp)
-       {
-         int e = errno;
-         close (dupfd);
-         errno = e;
-       }
-    }
-
   if (! dirp)
     savedir_error (dir);
 
@@ -734,19 +720,29 @@ scan_directory (struct tar_stat_info *st)
            *entry = 'N';
          else
            {
+             int fd = st->fd;
              void (*diag) (char const *) = 0;
              struct tar_stat_info stsub;
              tar_stat_init (&stsub);
 
-             if (fstatat (fd, entry + 1, &stsub.stat, fstatat_flags) != 0)
+             if (fd < 0)
+               {
+                 errno = - fd;
+                 diag = open_diag;
+               }
+             else if (fstatat (fd, entry + 1, &stsub.stat, fstatat_flags) != 0)
                diag = stat_diag;
              else if (S_ISDIR (stsub.stat.st_mode))
                {
-                 stsub.fd = openat (fd, entry + 1, open_read_flags);
-                 if (stsub.fd < 0)
+                 int subfd = subfile_open (st, entry + 1, open_read_flags);
+                 if (subfd < 0)
                    diag = open_diag;
-                 else if (fstat (stsub.fd, &stsub.stat) != 0)
-                   diag = stat_diag;
+                 else
+                   {
+                     stsub.fd = subfd;
+                     if (fstat (subfd, &stsub.stat) != 0)
+                       diag = stat_diag;
+                   }
                }
 
              if (diag)
@@ -762,7 +758,10 @@ scan_directory (struct tar_stat_info *st)
                  else if (directory->children == ALL_CHILDREN)
                    pd_flag |= PD_FORCE_CHILDREN | ALL_CHILDREN;
                  *entry = 'D';
+
+                 stsub.parent = st;
                  procdir (full_name, &stsub, pd_flag, entry);
+                 restore_parent_fd (&stsub);
                }
              else if (one_file_system_option && device != stsub.stat.st_dev)
                *entry = 'N';