Refactor stat cache handling into a function. Consistenly use

lstat(2) as no symlink sohuld ever be referenced at this point.
After unlink(2)/rmdir(2) operations ensure that the stat cache
is reset.

SVN-Revision: 42

diff --git a/libarchive/archive_write_disk.c b/libarchive/archive_write_disk.c
index b67903ad85dadd1142ecc1e607c94daf429a6fc4..38ed2fc7467fb7c9bbafc1b3c5cd7951dcca87e2 100644 (file)
--- a/libarchive/archive_write_disk.c
+++ b/libarchive/archive_write_disk.c
@@ -242,6 +242,31 @@ static int _archive_write_finish_entry(struct archive *);
 static ssize_t _archive_write_data(struct archive *, const void *, size_t);
 static ssize_t _archive_write_data_block(struct archive *, const void *, size_t, off_t);
 
+static int
+_archive_write_disk_lazy_stat(struct archive_write_disk *a)
+{
+       if (a->pst != NULL) {
+               /* Already have stat() data available. */
+               return (ARCHIVE_OK);
+       }
+#ifdef HAVE_FSTAT
+       if (a->fd >= 0 && fstat(a->fd, &a->st) == 0) {
+               a->pst = &a->st;
+               return (ARCHIVE_OK);
+       }
+#endif
+       /*
+        * XXX At this point, symlinks should not be hit, otherwise
+        * XXX a race occured.  Do we want to check explicitly for that?
+        */
+       if (lstat(a->name, &a->st) == 0) {
+               a->pst = &a->st;
+               return (ARCHIVE_OK);
+       }
+       archive_set_error(&a->archive, errno, "Couldn't stat file");
+       return (ARCHIVE_WARN);
+}
+
 static struct archive_vtable *
 archive_write_disk_vtable(void)
 {
@@ -725,11 +750,13 @@ restore_entry(struct archive_write_disk *a)
                 * object isn't a dir.
                 */
                if (unlink(a->name) == 0) {
-                       /* We removed it, we're done. */
+                       /* We removed it, reset cached stat. */
+                       a->pst = NULL;
                } else if (errno == ENOENT) {
                        /* File didn't exist, that's just as good. */
                } else if (rmdir(a->name) == 0) {
                        /* It was a dir, but now it's gone. */
+                       a->pst = NULL;
                } else {
                        /* We tried, but couldn't get rid of it. */
                        archive_set_error(&a->archive, errno,
@@ -770,6 +797,7 @@ restore_entry(struct archive_write_disk *a)
                            "Can't remove already-existing dir");
                        return (ARCHIVE_WARN);
                }
+               a->pst = NULL;
                /* Try again. */
                en = create_filesystem_object(a);
        } else if (en == EEXIST) {
@@ -809,6 +837,7 @@ restore_entry(struct archive_write_disk *a)
                                    "Can't unlink already-existing object");
                                return (ARCHIVE_WARN);
                        }
+                       a->pst = NULL;
                        /* Try again. */
                        en = create_filesystem_object(a);
                } else if (!S_ISDIR(a->mode)) {
@@ -1215,6 +1244,7 @@ check_symlinks(struct archive_write_disk *a)
                                        pn[0] = c;
                                        return (ARCHIVE_WARN);
                                }
+                               a->pst = NULL;
                                /*
                                 * Even if we did remove it, a warning
                                 * is in order.  The warning is silly,
@@ -1238,6 +1268,7 @@ check_symlinks(struct archive_write_disk *a)
                                        pn[0] = c;
                                        return (ARCHIVE_WARN);
                                }
+                               a->pst = NULL;
                        } else {
                                archive_set_error(&a->archive, 0,
                                    "Cannot extract through symlink %s",
@@ -1620,19 +1651,8 @@ set_mode(struct archive_write_disk *a, int mode)
                 * process, since systems sometimes set GID from
                 * the enclosing dir or based on ACLs.
                 */
-               if (a->pst != NULL) {
-                       /* Already have stat() data available. */
-#ifdef HAVE_FSTAT
-               } else if (a->fd >= 0 && fstat(a->fd, &a->st) == 0) {
-                       a->pst = &a->st;
-#endif
-               } else if (stat(a->name, &a->st) == 0) {
-                       a->pst = &a->st;
-               } else {
-                       archive_set_error(&a->archive, errno,
-                           "Couldn't stat file");
-                       return (ARCHIVE_WARN);
-               }
+               if ((r = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK)
+                       return (r);
                if (a->pst->st_gid != a->gid) {
                        mode &= ~ S_ISGID;
                        if (a->flags & ARCHIVE_EXTRACT_OWNER) {
@@ -1795,6 +1815,8 @@ static int
 set_fflags_platform(struct archive_write_disk *a, int fd, const char *name,
     mode_t mode, unsigned long set, unsigned long clear)
 {
+       int r;
+
        (void)mode; /* UNUSED */
        if (set == 0  && clear == 0)
                return (ARCHIVE_OK);
@@ -1805,15 +1827,8 @@ set_fflags_platform(struct archive_write_disk *a, int fd, const char *name,
         * about the correct approach if we're overwriting an existing
         * file that already has flags on it. XXX
         */
-       if (fd >= 0 && fstat(fd, &a->st) == 0)
-               a->pst = &a->st;
-       else if (lstat(name, &a->st) == 0)
-               a->pst = &a->st;
-       else {
-               archive_set_error(&a->archive, errno,
-                   "Couldn't stat file");
-               return (ARCHIVE_WARN);
-       }
+       if ((r = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK)
+               return (r);
 
        a->st.st_flags &= ~clear;
        a->st.st_flags |= set;