Handle "I can't map this for that file format" better.

For cases where record (meta)data is something that can't be written out
in a particular file format, return WTAP_ERR_UNWRITABLE_REC_DATA along
with an err_info string.

Report (and free) that err_info string in cases where
WTAP_ERR_UNWRITABLE_REC_DATA is returned.

Clean up some other error reporting cases, and flag with an XXX some
cases where we aren't reporting errors at all, while we're at it.

Change-Id: I91d02093af0d42c24ec4634c2c773b30f3d39ab3
Reviewed-on: https://code.wireshark.org/review/5823
Reviewed-by: Guy Harris <guy@alum.mit.edu>

25 files changed, 63 insertions, 48 deletions

diff --git a/wiretap/5views.c b/wiretap/5views.c
index aa5dd9afa9..67de759c1d 100644
--- a/wiretap/5views.c
+++ b/wiretap/5views.c
@@ -106,7 +106,7 @@ static gboolean _5views_seek_read(wtap *wth, gint64 seek_off,
 static int _5views_read_header(wtap *wth, FILE_T fh, t_5VW_TimeStamped_Header *hdr,
     struct wtap_pkthdr *phdr, int *err, gchar **err_info);
 
-static gboolean _5views_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr, const guint8 *pd, int *err);
+static gboolean _5views_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr, const guint8 *pd, int *err, gchar **err_info);
 static gboolean _5views_dump_close(wtap_dumper *wdh, int *err);
 
 
@@ -351,7 +351,7 @@ gboolean _5views_dump_open(wtap_dumper *wdh, int *err)
    Returns TRUE on success, FALSE on failure. */
 static gboolean _5views_dump(wtap_dumper *wdh,
 	const struct wtap_pkthdr *phdr,
-	const guint8 *pd, int *err)
+	const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	_5views_dump_t *_5views = (_5views_dump_t *)wdh->priv;
 	t_5VW_TimeStamped_Header HeaderFrame;
diff --git a/wiretap/btsnoop.c b/wiretap/btsnoop.c
index af10c3c86d..ee6231e3b2 100644
--- a/wiretap/btsnoop.c
+++ b/wiretap/btsnoop.c
@@ -281,10 +281,10 @@ static guint8 btsnoop_lookup_flags(guint8 hci_type, gboolean sent, guint8 *flags
     return FALSE;
 }
 
-static gboolean btsnoop_dump_partial_rec_hdr(wtap_dumper *wdh _U_,
+static gboolean btsnoop_format_partial_rec_hdr(
     const struct wtap_pkthdr *phdr,
     const union wtap_pseudo_header *pseudo_header,
-    const guint8 *pd, int *err,
+    const guint8 *pd, int *err, gchar **err_info,
     struct btsnooprec_hdr *rec_hdr)
 {
     gint64 ts_usec;
@@ -292,7 +292,10 @@ static gboolean btsnoop_dump_partial_rec_hdr(wtap_dumper *wdh _U_,
     guint8 flags = 0;
 
     if (!btsnoop_lookup_flags(*pd, pseudo_header->p2p.sent, &flags)) {
-        *err = WTAP_ERR_UNSUPPORTED;
+        *err = WTAP_ERR_UNWRITABLE_REC_DATA;
+        *err_info = g_strdup_printf("btsnoop: hci_type 0x%02x for %s data isn't supported",
+                                    *pd,
+                                    pseudo_header->p2p.sent ? "sent" : "received");
         return FALSE;
     }
 
@@ -310,7 +313,7 @@ static gboolean btsnoop_dump_partial_rec_hdr(wtap_dumper *wdh _U_,
 /* FIXME: How do we support multiple backends?*/
 static gboolean btsnoop_dump_h1(wtap_dumper *wdh,
     const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info)
 {
     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
     struct btsnooprec_hdr rec_hdr;
@@ -330,7 +333,8 @@ static gboolean btsnoop_dump_h1(wtap_dumper *wdh,
         return FALSE;
     }
 
-    if (!btsnoop_dump_partial_rec_hdr(wdh, phdr, pseudo_header, pd, err, &rec_hdr))
+    if (!btsnoop_format_partial_rec_hdr(phdr, pseudo_header, pd, err, err_info,
+                                        &rec_hdr))
         return FALSE;
 
     rec_hdr.incl_len = GUINT32_TO_BE(phdr->caplen-1);
@@ -354,7 +358,7 @@ static gboolean btsnoop_dump_h1(wtap_dumper *wdh,
 
 static gboolean btsnoop_dump_h4(wtap_dumper *wdh,
     const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info)
 {
     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
     struct btsnooprec_hdr rec_hdr;
@@ -371,7 +375,8 @@ static gboolean btsnoop_dump_h4(wtap_dumper *wdh,
         return FALSE;
     }
 
-    if (!btsnoop_dump_partial_rec_hdr(wdh, phdr, pseudo_header, pd, err, &rec_hdr))
+    if (!btsnoop_format_partial_rec_hdr(phdr, pseudo_header, pd, err, err_info,
+                                        &rec_hdr))
         return FALSE;
 
     rec_hdr.incl_len = GUINT32_TO_BE(phdr->caplen);
diff --git a/wiretap/catapult_dct2000.c b/wiretap/catapult_dct2000.c
index 28c60093b0..59ed3958df 100644
--- a/wiretap/catapult_dct2000.c
+++ b/wiretap/catapult_dct2000.c
@@ -111,7 +111,7 @@ static gboolean catapult_dct2000_seek_read(wtap *wth, gint64 seek_off,
 static void catapult_dct2000_close(wtap *wth);
 
 static gboolean catapult_dct2000_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-                                      const guint8 *pd, int *err);
+                                      const guint8 *pd, int *err, gchar **err_info);
 
 
 /************************************************************/
@@ -586,7 +586,7 @@ catapult_dct2000_dump_can_write_encap(int encap)
 
 static gboolean
 catapult_dct2000_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-                      const guint8 *pd, int *err)
+                      const guint8 *pd, int *err, gchar **err_info _U_)
 {
     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
     guint32 n;
diff --git a/wiretap/commview.c b/wiretap/commview.c
index c82fdbb51a..6c410f950e 100644
--- a/wiretap/commview.c
+++ b/wiretap/commview.c
@@ -86,7 +86,7 @@ static gboolean commview_seek_read(wtap *wth, gint64 seek_off,
 static gboolean commview_read_header(commview_header_t *cv_hdr, FILE_T fh,
 				     int *err, gchar **err_info);
 static gboolean commview_dump(wtap_dumper *wdh,	const struct wtap_pkthdr *phdr,
-			      const guint8 *pd, int *err);
+			      const guint8 *pd, int *err, gchar **err_info);
 
 wtap_open_return_val commview_open(wtap *wth, int *err, gchar **err_info)
 {
@@ -314,7 +314,7 @@ gboolean commview_dump_open(wtap_dumper *wdh, int *err _U_)
  * Returns TRUE on success, FALSE on failure. */
 static gboolean commview_dump(wtap_dumper *wdh,
 			      const struct wtap_pkthdr *phdr,
-			      const guint8 *pd, int *err)
+			      const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	commview_header_t cv_hdr;
 	struct tm *tm;
diff --git a/wiretap/erf.c b/wiretap/erf.c
index b6a984a82e..acf06057f6 100644
--- a/wiretap/erf.c
+++ b/wiretap/erf.c
@@ -592,7 +592,8 @@ static gboolean erf_dump(
     wtap_dumper                    *wdh,
     const struct wtap_pkthdr       *phdr,
     const guint8                   *pd,
-    int                            *err)
+    int                            *err,
+    gchar                          **err_info _U_)
 {
   const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
   union wtap_pseudo_header other_phdr;
diff --git a/wiretap/eyesdn.c b/wiretap/eyesdn.c
index 83daf82186..25e046edd6 100644
--- a/wiretap/eyesdn.c
+++ b/wiretap/eyesdn.c
@@ -356,7 +356,7 @@ esc_write(wtap_dumper *wdh, const guint8 *buf, int len, int *err)
 
 static gboolean eyesdn_dump(wtap_dumper *wdh,
 			    const struct wtap_pkthdr *phdr,
-			    const guint8 *pd, int *err);
+			    const guint8 *pd, int *err, gchar **err_info);
 
 gboolean eyesdn_dump_open(wtap_dumper *wdh, int *err)
 {
@@ -393,7 +393,7 @@ int eyesdn_dump_can_write_encap(int encap)
  *    Returns TRUE on success, FALSE on failure. */
 static gboolean eyesdn_dump(wtap_dumper *wdh,
 			    const struct wtap_pkthdr *phdr,
-			    const guint8 *pd, int *err)
+			    const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	static const guint8 start_flag = 0xff;
 	const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
diff --git a/wiretap/file_access.c b/wiretap/file_access.c
index 018045cf61..c475ffd6a6 100644
--- a/wiretap/file_access.c
+++ b/wiretap/file_access.c
@@ -2316,9 +2316,9 @@ wtap_dump_open_finish(wtap_dumper *wdh, int file_type_subtype, gboolean compress
 
 gboolean
 wtap_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-	  const guint8 *pd, int *err)
+	  const guint8 *pd, int *err, gchar **err_info)
 {
-	return (wdh->subtype_write)(wdh, phdr, pd, err);
+	return (wdh->subtype_write)(wdh, phdr, pd, err, err_info);
 }
 
 void
diff --git a/wiretap/k12.c b/wiretap/k12.c
index 934e8d4ec5..af1f4d84ca 100644
--- a/wiretap/k12.c
+++ b/wiretap/k12.c
@@ -1249,7 +1249,7 @@ static void k12_dump_src_setting(gpointer k _U_, gpointer v, gpointer p) {
 }
 
 static gboolean k12_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-                         const guint8 *pd, int *err) {
+                         const guint8 *pd, int *err, gchar **err_info _U_) {
     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
     k12_dump_t *k12 = (k12_dump_t *)wdh->priv;
     guint32 len;
diff --git a/wiretap/k12text.l b/wiretap/k12text.l
index f203fa7edb..f5192cadd0 100644
--- a/wiretap/k12text.l
+++ b/wiretap/k12text.l
@@ -369,7 +369,7 @@ static const struct { int e; const char* s; } encaps[] = {
 
 static gboolean
 k12text_dump(wtap_dumper *wdh _U_, const struct wtap_pkthdr *phdr,
-	     const guint8 *pd, int *err) {
+	     const guint8 *pd, int *err, gchar **err_info _U_) {
 #define K12BUF_SIZE 196808
 	char *buf;
 	size_t left = K12BUF_SIZE;
diff --git a/wiretap/lanalyzer.c b/wiretap/lanalyzer.c
index bac54fa204..26655cdb12 100644
--- a/wiretap/lanalyzer.c
+++ b/wiretap/lanalyzer.c
@@ -625,7 +625,7 @@ static void my_timersub(const struct timeval *a,
  *---------------------------------------------------*/
 static gboolean lanalyzer_dump(wtap_dumper *wdh,
 	const struct wtap_pkthdr *phdr,
-	const guint8 *pd, int *err)
+	const guint8 *pd, int *err, gchar **err_info _U_)
 {
       double x;
       int    i;
diff --git a/wiretap/libpcap.c b/wiretap/libpcap.c
index c6141cd1db..0aebcc30c7 100644
--- a/wiretap/libpcap.c
+++ b/wiretap/libpcap.c
@@ -67,7 +67,7 @@ static gboolean libpcap_seek_read(wtap *wth, gint64 seek_off,
 static gboolean libpcap_read_packet(wtap *wth, FILE_T fh,
     struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
 static gboolean libpcap_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static int libpcap_read_header(wtap *wth, FILE_T fh, int *err, gchar **err_info,
     struct pcaprec_ss990915_hdr *hdr);
 
@@ -889,7 +889,7 @@ gboolean libpcap_dump_open(wtap_dumper *wdh, int *err)
    Returns TRUE on success, FALSE on failure. */
 static gboolean libpcap_dump(wtap_dumper *wdh,
 	const struct wtap_pkthdr *phdr,
-	const guint8 *pd, int *err)
+	const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 	struct pcaprec_ss990915_hdr rec_hdr;
diff --git a/wiretap/logcat.c b/wiretap/logcat.c
index a10cc7544e..de11a42958 100644
--- a/wiretap/logcat.c
+++ b/wiretap/logcat.c
@@ -312,7 +312,7 @@ int logcat_dump_can_write_encap(int encap)
 
 static gboolean logcat_binary_dump(wtap_dumper *wdh,
     const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info _U_)
 {
     int caplen;
 
diff --git a/wiretap/logcat_text.c b/wiretap/logcat_text.c
index 96ec2cb656..c7bad0d7cf 100644
--- a/wiretap/logcat_text.c
+++ b/wiretap/logcat_text.c
@@ -404,7 +404,7 @@ int logcat_text_long_dump_can_write_encap(int encap) {
 
 static gboolean logcat_text_dump_text(wtap_dumper *wdh,
     const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info)
 {
     gchar                          *buf;
     gint                            length;
@@ -474,7 +474,9 @@ static gboolean logcat_text_dump_text(wtap_dumper *wdh,
             msg_pre_skip = 1 + (gint) strlen(tag) + 1;
             msg_begin = msg_payload + msg_pre_skip;
         } else {
-            *err = WTAP_ERR_UNSUPPORTED;
+            *err = WTAP_ERR_UNWRITABLE_REC_DATA;
+            *err_info = g_strdup_printf("logcat: version %d isn't supported",
+                                        logcat_version);
             return FALSE;
         }
 
diff --git a/wiretap/netmon.c b/wiretap/netmon.c
index e9f50ce204..a8648493da 100644
--- a/wiretap/netmon.c
+++ b/wiretap/netmon.c
@@ -183,7 +183,7 @@ static gboolean netmon_read_atm_pseudoheader(FILE_T fh,
     union wtap_pseudo_header *pseudo_header, int *err, gchar **err_info);
 static void netmon_sequential_close(wtap *wth);
 static gboolean netmon_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static gboolean netmon_dump_close(wtap_dumper *wdh, int *err);
 
 wtap_open_return_val netmon_open(wtap *wth, int *err, gchar **err_info)
@@ -993,7 +993,7 @@ gboolean netmon_dump_open(wtap_dumper *wdh, int *err)
 /* Write a record for a packet to a dump file.
    Returns TRUE on success, FALSE on failure. */
 static gboolean netmon_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 	netmon_dump_t *netmon = (netmon_dump_t *)wdh->priv;
diff --git a/wiretap/netscaler.c b/wiretap/netscaler.c
index 7d3fb9da6b..e8a0eb5ae5 100644
--- a/wiretap/netscaler.c
+++ b/wiretap/netscaler.c
@@ -640,7 +640,7 @@ static gboolean nstrace_set_start_time(wtap *wth);
 static guint64 ns_hrtime2nsec(guint32 tm);
 
 static gboolean nstrace_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-                             const guint8 *pd, int *err);
+                             const guint8 *pd, int *err, gchar **err_info);
 
 
 /*
@@ -1784,7 +1784,7 @@ nstrace_add_abstime(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
 /* Write a record for a packet to a dump file.
    Returns TRUE on success, FALSE on failure. */
 static gboolean nstrace_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info _U_)
 {
     nstrace_dump_t *nstrace = (nstrace_dump_t *)wdh->priv;
 
diff --git a/wiretap/nettl.c b/wiretap/nettl.c
index 88d42e6e8f..cb885661f9 100644
--- a/wiretap/nettl.c
+++ b/wiretap/nettl.c
@@ -183,7 +183,7 @@ static gboolean nettl_seek_read(wtap *wth, gint64 seek_off,
 static gboolean nettl_read_rec(wtap *wth, FILE_T fh, struct wtap_pkthdr *phdr,
 		Buffer *buf, int *err, gchar **err_info);
 static gboolean nettl_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 
 wtap_open_return_val nettl_open(wtap *wth, int *err, gchar **err_info)
 {
@@ -682,7 +682,7 @@ gboolean nettl_dump_open(wtap_dumper *wdh, int *err)
    Returns TRUE on success, FALSE on failure. */
 static gboolean nettl_dump(wtap_dumper *wdh,
         const struct wtap_pkthdr *phdr,
-        const guint8 *pd, int *err)
+        const guint8 *pd, int *err, gchar **err_info _U_)
 {
         const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
         struct nettlrec_hdr rec_hdr;
diff --git a/wiretap/network_instruments.c b/wiretap/network_instruments.c
index 7eb647b575..bf96b30cf8 100644
--- a/wiretap/network_instruments.c
+++ b/wiretap/network_instruments.c
@@ -108,7 +108,7 @@ static int read_packet_data(FILE_T fh, int offset_to_frame, int current_offset_f
 static gboolean skip_to_next_packet(wtap *wth, int offset_to_next_packet,
     int current_offset_from_packet_header, int *err, char **err_info);
 static gboolean observer_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static gint observer_to_wtap_encap(int observer_encap);
 static gint wtap_to_observer_encap(int wtap_encap);
 
@@ -668,7 +668,7 @@ gboolean network_instruments_dump_open(wtap_dumper *wdh, int *err)
    Returns TRUE on success, FALSE on failure. */
 static gboolean observer_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
     const guint8 *pd,
-    int *err)
+    int *err, gchar **err_info _U_)
 {
     observer_dump_private_state * private_state = NULL;
     packet_entry_header           packet_header;
diff --git a/wiretap/netxray.c b/wiretap/netxray.c
index fa047ccaca..69136373e0 100644
--- a/wiretap/netxray.c
+++ b/wiretap/netxray.c
@@ -412,11 +412,11 @@ static void netxray_guess_atm_type(wtap *wth, struct wtap_pkthdr *phdr,
     Buffer *buf);
 static gboolean netxray_dump_1_1(wtap_dumper *wdh,
     const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static gboolean netxray_dump_close_1_1(wtap_dumper *wdh, int *err);
 static gboolean netxray_dump_2_0(wtap_dumper *wdh,
     const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static gboolean netxray_dump_close_2_0(wtap_dumper *wdh, int *err);
 
 wtap_open_return_val
@@ -1728,7 +1728,7 @@ netxray_dump_open_1_1(wtap_dumper *wdh, int *err)
 static gboolean
 netxray_dump_1_1(wtap_dumper *wdh,
 		 const struct wtap_pkthdr *phdr,
-		 const guint8 *pd, int *err)
+		 const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	netxray_dump_t *netxray = (netxray_dump_t *)wdh->priv;
 	guint64 timestamp;
@@ -1906,7 +1906,7 @@ netxray_dump_open_2_0(wtap_dumper *wdh, int *err)
 static gboolean
 netxray_dump_2_0(wtap_dumper *wdh,
 		 const struct wtap_pkthdr *phdr,
-		 const guint8 *pd, int *err)
+		 const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 	netxray_dump_t *netxray = (netxray_dump_t *)wdh->priv;
diff --git a/wiretap/ngsniffer.c b/wiretap/ngsniffer.c
index 06ba78468b..60ad2e113e 100644
--- a/wiretap/ngsniffer.c
+++ b/wiretap/ngsniffer.c
@@ -528,7 +528,7 @@ static int fix_pseudo_header(int encap, Buffer *buf, int len,
 static void ngsniffer_sequential_close(wtap *wth);
 static void ngsniffer_close(wtap *wth);
 static gboolean ngsniffer_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static gboolean ngsniffer_dump_close(wtap_dumper *wdh, int *err);
 static int SnifferDecompress( unsigned char * inbuf, size_t inlen,
     unsigned char * outbuf, size_t outlen, int *err, gchar **err_info );
@@ -1993,7 +1993,7 @@ ngsniffer_dump_open(wtap_dumper *wdh, int *err)
    Returns TRUE on success, FALSE on failure. */
 static gboolean
 ngsniffer_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-	       const guint8 *pd, int *err)
+	       const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 	ngsniffer_dump_t *ngsniffer = (ngsniffer_dump_t *)wdh->priv;
diff --git a/wiretap/pcapng.c b/wiretap/pcapng.c
index 41edb34007..5ad679091a 100644
--- a/wiretap/pcapng.c
+++ b/wiretap/pcapng.c
@@ -3694,7 +3694,7 @@ pcapng_write_name_resolution_block(wtap_dumper *wdh, int *err)
 
 static gboolean pcapng_dump(wtap_dumper *wdh,
                             const struct wtap_pkthdr *phdr,
-                            const guint8 *pd, int *err)
+                            const guint8 *pd, int *err, gchar **err_info _U_)
 {
     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 #ifdef HAVE_PLUGINS
diff --git a/wiretap/snoop.c b/wiretap/snoop.c
index 88aecaf7a8..67816b438c 100644
--- a/wiretap/snoop.c
+++ b/wiretap/snoop.c
@@ -96,7 +96,7 @@ static gboolean snoop_read_shomiti_wireless_pseudoheader(FILE_T fh,
     union wtap_pseudo_header *pseudo_header, int *err, gchar **err_info,
     int *header_size);
 static gboolean snoop_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 
 /*
  * See
@@ -813,7 +813,7 @@ gboolean snoop_dump_open(wtap_dumper *wdh, int *err)
    Returns TRUE on success, FALSE on failure. */
 static gboolean snoop_dump(wtap_dumper *wdh,
 	const struct wtap_pkthdr *phdr,
-	const guint8 *pd, int *err)
+	const guint8 *pd, int *err, gchar **err_info _U_)
 {
 	const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 	struct snooprec_hdr rec_hdr;
diff --git a/wiretap/visual.c b/wiretap/visual.c
index 02acaf711b..01b353446b 100644
--- a/wiretap/visual.c
+++ b/wiretap/visual.c
@@ -165,7 +165,7 @@ static gboolean visual_seek_read(wtap *wth, gint64 seek_off,
 static gboolean visual_read_packet(wtap *wth, FILE_T fh,
     struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
 static gboolean visual_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err);
+    const guint8 *pd, int *err, gchar **err_info);
 static gboolean visual_dump_close(wtap_dumper *wdh, int *err);
 static void visual_dump_free(wtap_dumper *wdh);
 
@@ -642,7 +642,7 @@ gboolean visual_dump_open(wtap_dumper *wdh, int *err)
 /* Write a packet to a Visual dump file.
    Returns TRUE on success, FALSE on failure. */
 static gboolean visual_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
-    const guint8 *pd, int *err)
+    const guint8 *pd, int *err, gchar **err_info _U_)
 {
     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
     struct visual_write_info * visual = (struct visual_write_info *)wdh->priv;
diff --git a/wiretap/wtap-int.h b/wiretap/wtap-int.h
index c550502b81..6f63cfe939 100644
--- a/wiretap/wtap-int.h
+++ b/wiretap/wtap-int.h
@@ -95,7 +95,7 @@ typedef void *WFILE_T;
 
 typedef gboolean (*subtype_write_func)(struct wtap_dumper*,
                                        const struct wtap_pkthdr*,
-                                       const guint8*, int*);
+                                       const guint8*, int*, gchar**);
 typedef gboolean (*subtype_close_func)(struct wtap_dumper*, int*);
 
 struct wtap_dumper {
diff --git a/wiretap/wtap.c b/wiretap/wtap.c
index 74cab0901c..40cabd0821 100644
--- a/wiretap/wtap.c
+++ b/wiretap/wtap.c
@@ -883,7 +883,10 @@ static const char *wtap_errlist[] = {
 	NULL,
 
 	/* WTAP_ERR_REC_TYPE_UNSUPPORTED */
-	"That record type cannot be written in that format"
+	"That record type cannot be written in that format",
+
+	/* WTAP_ERR_UNWRITABLE_REC_DATA */
+	"That record can't be written in that format"
 };
 #define	WTAP_ERRLIST_SIZE	(sizeof wtap_errlist / sizeof wtap_errlist[0])
 
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index e7d80da355..5e707a24db 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -1562,7 +1562,8 @@ wtap_dumper* wtap_dump_fdopen_ng(int fd, int filetype, int encap, int snaplen,
 
 
 WS_DLL_PUBLIC
-gboolean wtap_dump(wtap_dumper *, const struct wtap_pkthdr *, const guint8 *, int *err);
+gboolean wtap_dump(wtap_dumper *, const struct wtap_pkthdr *, const guint8 *,
+     int *err, gchar **err_info);
 WS_DLL_PUBLIC
 void wtap_dump_flush(wtap_dumper *);
 WS_DLL_PUBLIC
@@ -1738,6 +1739,9 @@ int wtap_register_encap_type(const char* name, const char* short_name);
 #define WTAP_ERR_REC_TYPE_UNSUPPORTED         -24
     /** Specified record type can't be written to that file type */
 
+#define WTAP_ERR_UNWRITABLE_REC_DATA          -25
+    /** Something in the record data can't be written to that file type */
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */