Allow wtap_read() and wtap_seek_read() to return records other than packets.

Add a "record type" field to "struct wtap_pkthdr"; currently, it can be
REC_TYPE_PACKET, for a record containing a packet, or
REC_TYPE_FILE_TYPE_SPECIFIC, for records containing file-type-specific
data.

Modify code that reads packets to be able to handle non-packet records,
even if that just means ignoring them.

Rename some routines to indicate that they handle more than just
packets.

We don't yet have any libwiretap code that supplies records other than
REC_TYPE_PACKET or that supporting writing records other than
REC_TYPE_PACKET, or any code to support plugins for handling
REC_TYPE_FILE_TYPE_SPECIFIC records; this is just the first step for bug
8590.

Change-Id: Idb40b78f17c2c3aea72031bcd252abf9bc11c813
Reviewed-on: https://code.wireshark.org/review/1773
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 32 insertions, 31 deletions

diff --git a/file.c b/file.c
index e75a78d4f9..7630989115 100644
--- a/file.c
+++ b/file.c
@@ -1754,8 +1754,8 @@ cf_redissect_packets(capture_file *cf)
 }
 
 gboolean
-cf_read_frame_r(capture_file *cf, const frame_data *fdata,
-                struct wtap_pkthdr *phdr, Buffer *buf)
+cf_read_record_r(capture_file *cf, const frame_data *fdata,
+                 struct wtap_pkthdr *phdr, Buffer *buf)
 {
   int    err;
   gchar *err_info;
@@ -1807,9 +1807,9 @@ cf_read_frame_r(capture_file *cf, const frame_data *fdata,
 }
 
 gboolean
-cf_read_frame(capture_file *cf, frame_data *fdata)
+cf_read_record(capture_file *cf, frame_data *fdata)
 {
-  return cf_read_frame_r(cf, fdata, &cf->phdr, &cf->buf);
+  return cf_read_record_r(cf, fdata, &cf->phdr, &cf->buf);
 }
 
 /* Rescan the list of packets, reconstructing the CList.
@@ -2005,7 +2005,7 @@ rescan_packets(capture_file *cf, const char *action, const char *action_item, gb
     /* Frame dependencies from the previous dissection/filtering are no longer valid. */
     fdata->flags.dependent_of_displayed = 0;
 
-    if (!cf_read_frame(cf, fdata))
+    if (!cf_read_record(cf, fdata))
       break; /* error reading the frame */
 
     /* If the previous frame is displayed, and we haven't yet seen the
@@ -2230,7 +2230,7 @@ typedef enum {
 } psp_return_t;
 
 static psp_return_t
-process_specified_packets(capture_file *cf, packet_range_t *range,
+process_specified_records(capture_file *cf, packet_range_t *range,
     const char *string1, const char *string2, gboolean terminate_is_stop,
     gboolean (*callback)(capture_file *, frame_data *,
                          struct wtap_pkthdr *, const guint8 *, void *),
@@ -2332,7 +2332,7 @@ process_specified_packets(capture_file *cf, packet_range_t *range,
     }
 
     /* Get the packet */
-    if (!cf_read_frame_r(cf, fdata, &phdr, &buf)) {
+    if (!cf_read_record_r(cf, fdata, &phdr, &buf)) {
       /* Attempt to get the packet failed. */
       ret = PSP_FAILED;
       break;
@@ -2411,7 +2411,7 @@ cf_retap_packets(capture_file *cf)
   packet_range_init(&range, cf);
   packet_range_process_init(&range);
 
-  ret = process_specified_packets(cf, &range, "Recalculating statistics on",
+  ret = process_specified_records(cf, &range, "Recalculating statistics on",
                                   "all packets", TRUE, retap_packet,
                                   &callback_args);
 
@@ -2724,7 +2724,7 @@ cf_print_packets(capture_file *cf, print_args_t *print_args)
 
   /* Iterate through the list of packets, printing the packets we were
      told to print. */
-  ret = process_specified_packets(cf, &print_args->range, "Printing",
+  ret = process_specified_records(cf, &print_args->range, "Printing",
                                   "selected packets", TRUE, print_packet,
                                   &callback_args);
   epan_dissect_cleanup(&callback_args.edt);
@@ -2815,7 +2815,7 @@ cf_write_pdml_packets(capture_file *cf, print_args_t *print_args)
 
   /* Iterate through the list of packets, printing the packets we were
      told to print. */
-  ret = process_specified_packets(cf, &print_args->range, "Writing PDML",
+  ret = process_specified_records(cf, &print_args->range, "Writing PDML",
                                   "selected packets", TRUE,
                                   write_pdml_packet, &callback_args);
 
@@ -2896,7 +2896,7 @@ cf_write_psml_packets(capture_file *cf, print_args_t *print_args)
 
   /* Iterate through the list of packets, printing the packets we were
      told to print. */
-  ret = process_specified_packets(cf, &print_args->range, "Writing PSML",
+  ret = process_specified_records(cf, &print_args->range, "Writing PSML",
                                   "selected packets", TRUE,
                                   write_psml_packet, &callback_args);
 
@@ -2976,7 +2976,7 @@ cf_write_csv_packets(capture_file *cf, print_args_t *print_args)
 
   /* Iterate through the list of packets, printing the packets we were
      told to print. */
-  ret = process_specified_packets(cf, &print_args->range, "Writing CSV",
+  ret = process_specified_records(cf, &print_args->range, "Writing CSV",
                                   "selected packets", TRUE,
                                   write_csv_packet, &callback_args);
 
@@ -3048,7 +3048,7 @@ cf_write_carrays_packets(capture_file *cf, print_args_t *print_args)
 
   /* Iterate through the list of packets, printing the packets we were
      told to print. */
-  ret = process_specified_packets(cf, &print_args->range,
+  ret = process_specified_records(cf, &print_args->range,
                   "Writing C Arrays",
                   "selected packets", TRUE,
                                   write_carrays_packet, &callback_args);
@@ -3109,7 +3109,7 @@ match_protocol_tree(capture_file *cf, frame_data *fdata, void *criterion)
   epan_dissect_t  edt;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3213,7 +3213,7 @@ match_summary_line(capture_file *cf, frame_data *fdata, void *criterion)
   size_t          c_match    = 0;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3311,7 +3311,7 @@ match_narrow_and_wide(capture_file *cf, frame_data *fdata, void *criterion)
   size_t        c_match    = 0;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3359,7 +3359,7 @@ match_narrow(capture_file *cf, frame_data *fdata, void *criterion)
   size_t        c_match    = 0;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3406,7 +3406,7 @@ match_wide(capture_file *cf, frame_data *fdata, void *criterion)
   size_t        c_match    = 0;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3452,7 +3452,7 @@ match_binary(capture_file *cf, frame_data *fdata, void *criterion)
   size_t        c_match     = 0;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3522,7 +3522,7 @@ match_dfilter(capture_file *cf, frame_data *fdata, void *criterion)
   match_result    result;
 
   /* Load the frame's data. */
-  if (!cf_read_frame(cf, fdata)) {
+  if (!cf_read_record(cf, fdata)) {
     /* Attempt to get the packet failed. */
     return MR_ERROR;
   }
@@ -3848,7 +3848,7 @@ cf_select_packet(capture_file *cf, int row)
   }
 
   /* Get the data in that frame. */
-  if (!cf_read_frame (cf, fdata)) {
+  if (!cf_read_record (cf, fdata)) {
     return;
   }
 
@@ -4028,7 +4028,7 @@ cf_get_comment(capture_file *cf, const frame_data *fd)
     memset(&phdr, 0, sizeof(struct wtap_pkthdr));
 
     buffer_init(&buf, 1500);
-    if (!cf_read_frame_r(cf, fd, &phdr, &buf))
+    if (!cf_read_record_r(cf, fd, &phdr, &buf))
       { /* XXX, what we can do here? */ }
 
     buffer_free(&buf);
@@ -4110,7 +4110,7 @@ typedef struct {
  * up a message box for the failure.
  */
 static gboolean
-save_packet(capture_file *cf _U_, frame_data *fdata,
+save_record(capture_file *cf _U_, frame_data *fdata,
             struct wtap_pkthdr *phdr, const guint8 *pd,
             void *argsp)
 {
@@ -4138,6 +4138,7 @@ save_packet(capture_file *cf _U_, frame_data *fdata,
 
      For WTAP_HAS_PACK_FLAGS, we currently don't save the FCS length
      from the packet flags. */
+  hdr.rec_type = phdr->rec_type;
   hdr.presence_flags = 0;
   if (fdata->flags.has_ts)
     hdr.presence_flags |= WTAP_HAS_TS;
@@ -4147,8 +4148,8 @@ save_packet(capture_file *cf _U_, frame_data *fdata,
     hdr.presence_flags |= WTAP_HAS_PACK_FLAGS;
   hdr.ts.secs      = fdata->abs_ts.secs;
   hdr.ts.nsecs     = fdata->abs_ts.nsecs;
-  hdr.caplen       = fdata->cap_len;
-  hdr.len          = fdata->pkt_len;
+  hdr.caplen       = phdr->caplen;
+  hdr.len          = phdr->len;
   hdr.pkt_encap    = fdata->lnk_t;
   /* pcapng */
   hdr.interface_id = phdr->interface_id;   /* identifier of the interface. */
@@ -4551,7 +4552,7 @@ rescan_file(capture_file *cf, const char *fname, gboolean is_tempfile, int *err)
 }
 
 cf_write_status_t
-cf_save_packets(capture_file *cf, const char *fname, guint save_format,
+cf_save_records(capture_file *cf, const char *fname, guint save_format,
                 gboolean compressed, gboolean discard_comments,
                 gboolean dont_reopen)
 {
@@ -4698,8 +4699,8 @@ cf_save_packets(capture_file *cf, const char *fname, guint save_format,
     callback_args.pdh = pdh;
     callback_args.fname = fname;
     callback_args.file_type = save_format;
-    switch (process_specified_packets(cf, NULL, "Saving", "packets",
-                                      TRUE, save_packet, &callback_args)) {
+    switch (process_specified_records(cf, NULL, "Saving", "packets",
+                                      TRUE, save_record, &callback_args)) {
 
     case PSP_FINISHED:
       /* Completed successfully. */
@@ -4927,14 +4928,14 @@ cf_export_specified_packets(capture_file *cf, const char *fname,
      told to process.
 
      XXX - we've already called "packet_range_process_init(range)", but
-     "process_specified_packets()" will do it again.  Fortunately,
+     "process_specified_records()" will do it again.  Fortunately,
      that's harmless in this case, as we haven't done anything to
      "range" since we initialized it. */
   callback_args.pdh = pdh;
   callback_args.fname = fname;
   callback_args.file_type = save_format;
-  switch (process_specified_packets(cf, range, "Writing", "specified packets",
-                                    TRUE, save_packet, &callback_args)) {
+  switch (process_specified_records(cf, range, "Writing", "specified records",
+                                    TRUE, save_record, &callback_args)) {
 
   case PSP_FINISHED:
     /* Completed successfully. */