More error checking; improve gdbm_recover

* Makefile.am (set-dist-date): New rule
(dist-hook): Catch FIXMEs in NEWS.
* NEWS: Updated.
* src/findkey.c (gdbm_bucket_element_valid_p): New function.
(_gdbm_read_entry): Validate the retrieved bucket element.
* src/gdbm.h.in (gdbm_recovery): New member: duplicate_keys.
(GDBM_BAD_HASH_TABLE): New error code.
* src/gdbmdefs.h (TYPE_WIDTH,SIGNED_TYPE_MAXIMUM)
(OFF_T_MAX): New defines.
(off_t_sum_ok): New function.
(gdbm_bucket_element_valid_p): New prototype.
* src/gdbmerrno.c: Support for GDBM_BAD_HASH_TABLE code.
* src/gdbmtool.c (recover_handler): Fix argument counting.
New argument 'summary' prints statistics summary at the end
of the run.
(export_handler,import_handler): Fix argument counting.
* src/mmap.c (SUM_FILE_SIZE): Rewrite as inlined function.
Add error checking.
(_gdbm_mapped_remap): More error checking.
* src/recover.c (run_recovery): Don't bail out on GDBM_CANNOT_REPLACE.
(gdbm_recover): Initialize duplicate_keys
* src/systems.h: Include limits.h

1 files changed, 20 insertions, 2 deletions

diff --git a/src/mmap.c b/src/mmap.c
index 114d8b2..24ede29 100644
--- a/src/mmap.c
+++ b/src/mmap.c
@@ -41,14 +41,21 @@
   ((off) >= (dbf)->mapped_off \
    && ((off) - (dbf)->mapped_off) < (dbf)->mapped_size)
 /* Return true if the current region needs to be remapped */
 # define _GDBM_NEED_REMAP(dbf) \
   (!(dbf)->mapped_region || (dbf)->mapped_pos == (dbf)->mapped_size)
 /* Return the sum of the currently mapped size and DELTA */
-# define SUM_FILE_SIZE(dbf, delta) \
-  ((dbf)->mapped_off + (dbf)->mapped_size + (delta))
+static inline off_t
+SUM_FILE_SIZE (GDBM_FILE dbf, off_t delta)
+{
+  if (delta >= 0
+      && off_t_sum_ok (dbf->mapped_off, dbf->mapped_size)
+      && off_t_sum_ok (dbf->mapped_off + dbf->mapped_size, delta))
+    return dbf->mapped_off + dbf->mapped_size + delta;
+  return -1;
+}
 
 /* Store the size of the GDBM file DBF in *PSIZE.
    Return 0 on success and -1 on failure. */
 int
 _gdbm_file_size (GDBM_FILE dbf, off_t *psize)
 {
@@ -179,12 +186,23 @@ _gdbm_file_extend (GDBM_FILE dbf, off_t size)
    The function returns 0 on success, -1 on failure. */
 int
 _gdbm_mapped_remap (GDBM_FILE dbf, off_t size, int flag)
 {
   off_t file_size, pos;
 
+  if (size < 0)
+    {
+      errno = EINVAL;
+      GDBM_SET_ERRNO (dbf, GDBM_FILE_SEEK_ERROR, TRUE);
+      return -1;
+    }
+
+  if (size < dbf->mapped_size)
+    /* Nothing to do */
+    return 0;
+  
   if (_gdbm_file_size (dbf, &file_size))
     {
       SAVE_ERRNO (_gdbm_mapped_unmap (dbf));
       return -1; 
     }