Add a routine to Wiretap that takes a file type value and an

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

diff --git a/wiretap/file_access.c b/wiretap/file_access.c
index a6c5f43f62b31ec3d029193144fc7e58bd5a4534..c6b77cc391c8733dd652021539cc9490ab48deaa 100644 (file)
--- a/wiretap/file_access.c
+++ b/wiretap/file_access.c
@@ -683,6 +683,89 @@ int wtap_get_num_file_types(void)
        return wtap_num_file_types;
 }
 
+/*
+ * Get a GArray of WTAP_FILE_ values for file types that can be used
+ * to save a file of a given type with a given WTAP_ENCAP_ type.
+ */
+static gboolean
+can_save_with_wiretap(int ft, int encap)
+{
+       /*
+        * To save a file in a given file format, we have to handle that
+        * format, and the code to handle that format must be able to
+        * write a file with that file's encapsulation type.
+        */
+       return wtap_dump_can_open(ft) &&
+           wtap_dump_can_write_encap(ft, encap);
+}
+
+GArray *
+wtap_get_savable_file_types(int file_type, int file_encap)
+{
+       GArray *savable_file_types;
+       int ft;
+       int default_file_type = -1;
+       int other_file_type = -1;
+
+       /* Can we save this file in its own file type? */
+       if (can_save_with_wiretap(file_type, file_encap)) {
+               /* Yes - make that the default file type. */
+               default_file_type = file_type;
+       } else {
+               /* No - can we save it as a pcap-NG file? */
+               if (can_save_with_wiretap(WTAP_FILE_PCAPNG, file_encap)) {
+                       /* Yes - default to pcap-NG, instead. */
+                       default_file_type = WTAP_FILE_PCAPNG;
+               } else {
+                       /* OK, find the first file type we *can* save it as. */
+                       default_file_type = -1;
+                       for (ft = 0; ft < WTAP_NUM_FILE_TYPES; ft++) {
+                               if (can_save_with_wiretap(ft, file_encap)) {
+                                       /* OK, got it. */
+                                       default_file_type = ft;
+                               }
+                       }
+               }
+       }
+
+       if (default_file_type == -1) {
+               /* We don't support writing this file as any file type. */
+               return NULL;
+       }
+
+       /* Allocate the array. */
+       savable_file_types = g_array_new(FALSE, FALSE, (guint)sizeof (int));
+
+       /* Put the default file format first in the list. */
+       g_array_append_val(savable_file_types, default_file_type);
+
+       /* If it's pcap, put pcap-NG right after it; otherwise, if it's
+          pcap-NG, put pcap right after it. */
+       if (default_file_type == WTAP_FILE_PCAP) {
+               if (can_save_with_wiretap(WTAP_FILE_PCAPNG, file_encap))
+                       other_file_type = WTAP_FILE_PCAPNG;
+       } else if (default_file_type == WTAP_FILE_PCAPNG) {
+               if (can_save_with_wiretap(WTAP_FILE_PCAP, file_encap))
+                       other_file_type = WTAP_FILE_PCAP;
+       }
+       if (other_file_type != -1)
+               g_array_append_val(savable_file_types, other_file_type);
+
+       /* Add all the other file types that work. */
+       for (ft = 0; ft < WTAP_NUM_FILE_TYPES; ft++) {
+               if (ft == WTAP_FILE_UNKNOWN)
+                       continue;       /* not a real file type */
+               if (ft == default_file_type || ft == other_file_type)
+                       continue;       /* we've already done this one */
+               if (can_save_with_wiretap(ft, file_encap)) {
+                       /* OK, we can write it out in this type. */
+                       g_array_append_val(savable_file_types, ft);
+               }
+       }
+
+       return savable_file_types;
+}
+
 /* Name that should be somewhat descriptive. */
 const char *wtap_file_type_string(int filetype)
 {