Check for errors in seeks, "tell"s, and "stat()"s/"fstat()"s.

For file types where we allocate private data, add "close" routines
where they were missing, to free the private data.  Also fix up the code
to clean up after some errors by freeing private data where that wasn't
being done.

Get rid of unused arguments to "wtap_dump_open_finish()".

Fix indentation.

svn path=/trunk/; revision=4857

1 files changed, 49 insertions, 18 deletions

diff --git a/wiretap/vms.c b/wiretap/vms.c
index f1e0760bf2..19af1bfbc1 100644
--- a/wiretap/vms.c
+++ b/wiretap/vms.c
@@ -1,6 +1,6 @@
 /* vms.c
  *
- * $Id: vms.c,v 1.7 2002/03/02 20:41:08 guy Exp $
+ * $Id: vms.c,v 1.8 2002/03/04 00:25:35 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 2001 by Marc Milgram <mmilgram@arrayinc.com>
@@ -18,8 +18,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
- *
  */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
@@ -80,12 +80,12 @@ static int parse_vms_rec_hdr(wtap *wth, FILE_T fh, int *err);
 
 
 /* Seeks to the beginning of the next packet, and returns the
-   byte offset.  Returns -1 on failure. */
-/* XXX - Handle I/O errors. */
-static long vms_seek_next_packet(wtap *wth)
+   byte offset.  Returns -1 on failure, and sets "*err" to the error. */
+static long vms_seek_next_packet(wtap *wth, int *err)
 {
   int byte;
   unsigned int level = 0;
+  long cur_off;
 
   while ((byte = file_getc(wth->fh)) != EOF) {
     if ((level == 3) && (byte != vms_rec_magic[level]))
@@ -93,13 +93,27 @@ static long vms_seek_next_packet(wtap *wth)
     if (byte == vms_rec_magic[level]) {
       level++;
       if (level >= VMS_REC_MAGIC_SIZE) {
-          /* note: we're leaving file pointer right after the magic characters */
-        return file_tell(wth->fh) + 1;
+        /* note: we're leaving file pointer right after the magic characters */
+        cur_off = file_tell(wth->fh);
+        if (cur_off == -1) {
+          /* Error. */
+          *err = file_error(wth->fh);
+          return -1;
+        }
+        return cur_off + 1;
       }
     } else {
       level = 0;
     }
   }
+  if (file_eof(wth->fh)) {
+    /* We got an EOF. */
+    *err = 0;
+  } else {
+    /* We (presumably) got an error (there's no equivalent to "ferror()"
+       in zlib, alas, so we don't have a wrapper to check for an error). */
+    *err = file_error(wth->fh);
+  }
   return -1;
 }
 
@@ -109,12 +123,13 @@ static long vms_seek_next_packet(wtap *wth)
 /* Look through the first part of a file to see if this is
  * a VMS trace file.
  *
- * Returns TRUE if it is, FALSE if it isn't.
+ * Returns TRUE if it is, FALSE if it isn't or if we get an I/O error;
+ * if we get an I/O error, "*err" will be set to a non-zero value.
  *
  * Leaves file handle at begining of line that contains the VMS Magic
  * identifier.
  */
-static gboolean vms_check_file_type(wtap *wth)
+static gboolean vms_check_file_type(wtap *wth, int *err)
 {
     char    buf[VMS_LINE_LENGTH];
     int    line, byte;
@@ -125,6 +140,11 @@ static gboolean vms_check_file_type(wtap *wth)
 
     for (line = 0; line < VMS_HEADER_LINES_TO_CHECK; line++) {
         mpos = file_tell(wth->fh);
+        if (mpos == -1) {
+            /* Error. */
+            *err = file_error(wth->fh);
+            return FALSE;
+        }
         if (file_gets(buf, VMS_LINE_LENGTH, wth->fh) != NULL) {
 
             reclen = strlen(buf);
@@ -139,7 +159,11 @@ static gboolean vms_check_file_type(wtap *wth)
                 if (byte == vms_hdr_magic[level]) {
                     level++;
                     if (level >= VMS_HDR_MAGIC_SIZE) {
-                        file_seek(wth->fh, mpos, SEEK_SET);
+                        if (file_seek(wth->fh, mpos, SEEK_SET) == -1) {
+                            /* Error. */
+                            *err = file_error(wth->fh);
+                            return FALSE;
+                        }
                         return TRUE;
                     }
                 }
@@ -147,19 +171,28 @@ static gboolean vms_check_file_type(wtap *wth)
                     level = 0;
             }
         }
-        else
+        else {
+            /* EOF or error. */
+            if (file_eof(wth->fh))
+                *err = 0;
+            else
+                *err = file_error(wth->fh);
             return FALSE;
+        }
     }
+    *err = 0;
     return FALSE;
 }
 
 
-/* XXX - return -1 on I/O error and actually do something with 'err'. */
 int vms_open(wtap *wth, int *err)
 {
     /* Look for VMS header */
-    if (!vms_check_file_type(wth)) {
-        return 0;
+    if (!vms_check_file_type(wth, err)) {
+        if (*err == 0)
+            return 0;
+        else
+            return -1;
     }
 
     wth->data_offset = 0;
@@ -180,11 +213,9 @@ static gboolean vms_read(wtap *wth, int *err, long *data_offset)
     int    pkt_len;
 
     /* Find the next packet */
-    offset = vms_seek_next_packet(wth);
-    if (offset < 1) {
-        *err = 0;    /* XXX - assume, for now, that it's an EOF */
+    offset = vms_seek_next_packet(wth, err);
+    if (offset < 1)
         return FALSE;
-    }
 
     /* Parse the header */
     pkt_len = parse_vms_rec_hdr(wth, wth->fh, err);