wiretap: eliminate two WTAP_FILE_TYPE_SUBTYPE_ values.

Eliminate WTAP_FILE_TYPE_SUBTYPE_ERF and
WTAP_FILE_TYPE_SUBTYPE_SYSTEMD_JOURNAL - instead, fetch the values by
name, using wtap_name_to_file_type_subtype().

This requires that wtap_init() be called before epan_init(); that's
currently the case, but put in comments to indicate why it must continue
to be the case.

4 files changed, 46 insertions, 19 deletions

diff --git a/wiretap/erf.c b/wiretap/erf.c
index 0d7245fc3e..6ecf2db74f 100644
--- a/wiretap/erf.c
+++ b/wiretap/erf.c
@@ -177,6 +177,10 @@ static gboolean erf_wtap_blocks_to_erf_sections(wtap_block_t block, GPtrArray *s
 
 static guint32 erf_meta_read_tag(struct erf_meta_tag*, guint8*, guint32);
 
+static int erf_file_type_subtype = -1;
+
+void register_erf(void);
+
 static guint erf_anchor_mapping_hash(gconstpointer key) {
   const struct erf_anchor_mapping *anchor_map = (const struct erf_anchor_mapping*) key;
 
@@ -542,7 +546,7 @@ extern wtap_open_return_val erf_open(wtap *wth, int *err, gchar **err_info)
   }
 
   /* This is an ERF file */
-  wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_ERF;
+  wth->file_type_subtype = erf_file_type_subtype;
   wth->snapshot_length = 0;     /* not available in header, only in frame */
 
   /*
@@ -707,7 +711,7 @@ static gboolean erf_read_header(wtap *wth, FILE_T fh,
   {
     guint64 ts = pletoh64(&erf_header->ts);
 
-    /*if ((erf_header->type & 0x7f) != ERF_TYPE_META || wth->file_type_subtype != WTAP_FILE_TYPE_SUBTYPE_ERF) {*/
+    /*if ((erf_header->type & 0x7f) != ERF_TYPE_META || wth->file_type_subtype != file_type_subtype_erf) {*/
       rec->rec_type = REC_TYPE_PACKET;
     /*
      * XXX: ERF_TYPE_META records should ideally be FT_SPECIFIC for display
@@ -3391,6 +3395,23 @@ static void erf_close(wtap *wth)
   wth->priv = NULL;
 }
 
+static const struct file_type_subtype_info erf_info = {
+  "Endace ERF capture", "erf", "erf", NULL,
+  FALSE, TRUE, WTAP_COMMENT_PER_SECTION|WTAP_COMMENT_PER_INTERFACE|WTAP_COMMENT_PER_PACKET,
+  erf_dump_can_write_encap, erf_dump_open, NULL
+};
+
+void register_erf(void)
+{
+  erf_file_type_subtype = wtap_register_file_type_subtypes(&erf_info);
+
+  /*
+   * Register name for backwards compatibility with the
+   * wtap_filetypes table in Lua.
+   */
+  wtap_register_backwards_compatibility_lua_name("ERF", erf_file_type_subtype);
+}
+
 /*
  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
  *
diff --git a/wiretap/file_access.c b/wiretap/file_access.c
index 86b92602df..bc5c0bda21 100644
--- a/wiretap/file_access.c
+++ b/wiretap/file_access.c
@@ -1285,16 +1285,6 @@ static const struct file_type_subtype_info file_type_subtype_table_base[] = {
 	{ "ASN.1 Basic Encoding Rules", "ber", NULL, NULL,
 	  FALSE, FALSE, 0,
 	  NULL, NULL, NULL },
-
-	/* WTAP_FILE_TYPE_SUBTYPE_ERF */
-	{ "Endace ERF capture", "erf", "erf", NULL,
-	  FALSE, TRUE, WTAP_COMMENT_PER_SECTION|WTAP_COMMENT_PER_INTERFACE|WTAP_COMMENT_PER_PACKET,
-	  erf_dump_can_write_encap, erf_dump_open, NULL },
-
-	/* WTAP_FILE_TYPE_SUBTYPE_SYSTEMD_JOURNAL */
-	{ "systemd journal export", "systemd_journal", NULL, NULL,
-	  FALSE, FALSE, 0,
-	  NULL, NULL, NULL }
 };
 
 #define N_DUMP_OPEN_TABLE_BASE_ENTRIES	(sizeof(file_type_subtype_table_base) / sizeof(struct file_type_subtype_info))
@@ -2841,10 +2831,6 @@ wtap_register_backwards_compatibility_lua_name(const char *name, int ft)
 		    WTAP_FILE_TYPE_SUBTYPE_IPTRACE_2_0);
 		wtap_register_backwards_compatibility_lua_name("BER",
 		    WTAP_FILE_TYPE_SUBTYPE_BER);
-		wtap_register_backwards_compatibility_lua_name("ERF",
-		    WTAP_FILE_TYPE_SUBTYPE_ERF);
-		wtap_register_backwards_compatibility_lua_name("SYSTEMD_JOURNAL",
-		    WTAP_FILE_TYPE_SUBTYPE_SYSTEMD_JOURNAL);
 	}
 	entry.name = name;
 	entry.ft = ft;
diff --git a/wiretap/systemd_journal.c b/wiretap/systemd_journal.c
index 4414404199..621241e8f8 100644
--- a/wiretap/systemd_journal.c
+++ b/wiretap/systemd_journal.c
@@ -62,6 +62,10 @@ static gboolean systemd_journal_read_export_entry(FILE_T fh, wtap_rec *rec,
 #define FLD__REALTIME_TIMESTAMP "__REALTIME_TIMESTAMP="
 #define FLD__MONOTONIC_TIMESTAMP "__MONOTONIC_TIMESTAMP="
 
+static int systemd_journal_file_type_subtype = -1;
+
+void register_systemd_journal(void);
+
 wtap_open_return_val systemd_journal_open(wtap *wth, int *err _U_, gchar **err_info _U_)
 {
     gchar *entry_buff = (gchar*) g_malloc(MAX_EXPORT_ENTRY_LENGTH);
@@ -97,7 +101,7 @@ wtap_open_return_val systemd_journal_open(wtap *wth, int *err _U_, gchar **err_i
         return WTAP_OPEN_NOT_MINE;
     }
 
-    wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_SYSTEMD_JOURNAL;
+    wth->file_type_subtype = systemd_journal_file_type_subtype;
     wth->subtype_read = systemd_journal_read;
     wth->subtype_seek_read = systemd_journal_seek_read;
     wth->file_encap = WTAP_ENCAP_SYSTEMD_JOURNAL;
@@ -232,6 +236,24 @@ systemd_journal_read_export_entry(FILE_T fh, wtap_rec *rec, Buffer *buf, int *er
     return TRUE;
 }
 
+static const struct file_type_subtype_info systemd_journal_info = {
+    "systemd journal export", "systemd_journal", NULL, NULL,
+    FALSE, FALSE, 0,
+    NULL, NULL, NULL
+};
+
+void register_systemd_journal(void)
+{
+  systemd_journal_file_type_subtype = wtap_register_file_type_subtypes(&systemd_journal_info);
+
+  /*
+   * Register name for backwards compatibility with the
+   * wtap_filetypes table in Lua.
+   */
+  wtap_register_backwards_compatibility_lua_name("SYSTEMD_JOURNAL",
+                                                 systemd_journal_file_type_subtype);
+}
+
 /*
  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
  *
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index 2a0ecfb4f8..40006d829f 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -312,8 +312,6 @@ extern "C" {
 #define WTAP_FILE_TYPE_SUBTYPE_IPTRACE_1_0                    9
 #define WTAP_FILE_TYPE_SUBTYPE_IPTRACE_2_0                   10
 #define WTAP_FILE_TYPE_SUBTYPE_BER                           11
-#define WTAP_FILE_TYPE_SUBTYPE_ERF                           12
-#define WTAP_FILE_TYPE_SUBTYPE_SYSTEMD_JOURNAL               13
 
 /* timestamp precision (currently only these values are supported) */
 #define WTAP_TSPREC_UNKNOWN    -2