Have a pseudo-header for Ethernet packets, giving the size of the FCS -

[obnox/wireshark/wip.git] / wiretap / lanalyzer.c

diff --git a/wiretap/lanalyzer.c b/wiretap/lanalyzer.c
index 0675da026d5e72a23579eaecc3a46a43997a38f5..6b27df5b18f0584b7586269d77a9bc17b3278e07 100644 (file)
--- a/wiretap/lanalyzer.c
+++ b/wiretap/lanalyzer.c
@@ -1,6 +1,6 @@
 /* lanalyzer.c
  *
- * $Id: lanalyzer.c,v 1.39 2003/07/29 20:30:00 guy Exp $
+ * $Id: lanalyzer.c,v 1.40 2003/10/01 07:11:47 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -118,6 +118,8 @@ static const gint8 LA_CyclicInformationFake[] = {
       };
 
 static gboolean lanalyzer_read(wtap *wth, int *err, long *data_offset);
+static gboolean lanalyzer_seek_read(wtap *wth, long seek_off,
+    union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err);
 static void     lanalyzer_close(wtap *wth);
 static gboolean lanalyzer_dump_close(wtap_dumper *wdh, int *err);
 
@@ -155,7 +157,7 @@ int lanalyzer_open(wtap *wth, int *err)
        wth->file_type = WTAP_FILE_LANALYZER;
        wth->capture.lanalyzer = g_malloc(sizeof(lanalyzer_t));
        wth->subtype_read = lanalyzer_read;
-       wth->subtype_seek_read = wtap_def_seek_read;
+       wth->subtype_seek_read = lanalyzer_seek_read;
        wth->subtype_close = lanalyzer_close;
        wth->snapshot_length = 0;
 
@@ -384,6 +386,44 @@ static gboolean lanalyzer_read(wtap *wth, int *err, long *data_offset)
        wth->phdr.caplen = packet_size;
        wth->phdr.pkt_encap = wth->file_encap;
 
+       switch (wth->file_encap) {
+
+       case WTAP_ENCAP_ETHERNET:
+               /* We assume there's no FCS in this frame. */
+               wth->pseudo_header.eth.fcs_len = 0;
+               break;
+       }
+
+       return TRUE;
+}
+
+static gboolean lanalyzer_seek_read(wtap *wth, long seek_off,
+    union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err)
+{
+       int bytes_read;
+
+       if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
+               return FALSE;
+
+       /*
+        * Read the packet data.
+        */
+       bytes_read = file_read(pd, sizeof(guint8), length, wth->random_fh);
+       if (bytes_read != length) {
+               *err = file_error(wth->random_fh);
+               if (*err == 0)
+                       *err = WTAP_ERR_SHORT_READ;
+               return FALSE;
+       }
+
+       switch (wth->file_encap) {
+
+       case WTAP_ENCAP_ETHERNET:
+               /* We assume there's no FCS in this frame. */
+               pseudo_header->eth.fcs_len = 0;
+               break;
+       }
+
        return TRUE;
 }