Factor out BustlePcapReader

1 files changed, 29 insertions, 46 deletions

diff --git a/c-sources/pcap-monitor.c b/c-sources/pcap-monitor.c
index 18b15e4..cb1d272 100644
--- a/c-sources/pcap-monitor.c
+++ b/c-sources/pcap-monitor.c
@@ -37,6 +37,8 @@
 #include <glib/gstdio.h>
 #include <gio/gunixinputstream.h>
 
+#include "pcap-reader.h"
+
 
 /* Prefix of name claimed by the connection that collects name owners. */
 const char *BUSTLE_MONITOR_NAME_PREFIX = "org.freedesktop.Bustle.Monitor.";
@@ -100,7 +102,7 @@ typedef struct _BustlePcapMonitor {
     /* If >= 0, master side of controlling terminal for dbus_monitor */
     int pt_master;
     GSource *dbus_monitor_source;
-    pcap_t *pcap_in;
+    BustlePcapReader *reader;
 
     /* output */
     gchar *filename;
@@ -230,7 +232,7 @@ bustle_pcap_monitor_dispose (GObject *object)
 
   g_clear_object (&self->cancellable);
   g_clear_pointer (&self->dbus_monitor_source, g_source_destroy);
-  g_clear_pointer (&self->pcap_in, pcap_close);
+  g_clear_object (&self->reader);
   g_clear_object (&self->dbus_monitor);
 
   close_dump (self);
@@ -654,7 +656,6 @@ start_pcap (
   GInputStream *stdout_pipe = NULL;
   gint stdout_fd = -1;
   FILE *dbus_monitor_filep = NULL;
-  char errbuf[PCAP_ERRBUF_SIZE] = {0};
 
   stdout_pipe = g_subprocess_get_stdout_pipe (self->dbus_monitor);
   g_return_val_if_fail (stdout_pipe != NULL, FALSE);
@@ -676,24 +677,17 @@ start_pcap (
    * fread(). It's safe to do this on the main thread, since we know the pipe
    * is readable. On short read, pcap_fopen_offline() fails immediately.
    */
-  self->pcap_in = pcap_fopen_offline (dbus_monitor_filep, errbuf);
-  if (self->pcap_in == NULL)
+  self->reader = bustle_pcap_reader_fopen (g_steal_pointer (&dbus_monitor_filep), error);
+  if (self->reader == NULL)
     {
-      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
-                   "Couldn't read messages from dbus-monitor: %s",
-                   errbuf);
-
-      /* Cause dbus-monitor to exit next time it tries to write a message */
-      g_clear_pointer (&dbus_monitor_filep, fclose);
+      g_prefix_error (error, "Couldn't read messages from dbus-monitor: ");
 
-      /* And try to terminate it immediately. */
+      /* Try to terminate dbus-monitor immediately. The reader closes the FILE * on error. */
       send_sigint (self);
 
       return FALSE;
     }
 
-  /* pcap_close() will call fclose() on the FILE * passed to
-   * pcap_fopen_offline() */
   dump_names_async (self);
   self->state = STATE_RUNNING;
   return TRUE;
@@ -706,41 +700,30 @@ read_one (
 {
   struct pcap_pkthdr *hdr;
   const guchar *blob;
-  int ret;
   g_autoptr(GDBusMessage) message = NULL;
 
-  ret = pcap_next_ex (self->pcap_in, &hdr, &blob);
-  switch (ret)
+  if (!bustle_pcap_reader_read_one (self->reader, &hdr, &blob, &message, error))
+    {
+      return FALSE;
+    }
+  else if (message == NULL)
     {
-      case 1:
-        message = g_dbus_message_new_from_blob ((guchar *) blob, hdr->caplen, G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING, error);
-        if (message == NULL)
-          {
-            g_prefix_error (error, "Error while parsing message from dbus-monitor: ");
-            return FALSE;
-          }
-
-        g_signal_emit (self, signals[SIG_MESSAGE_LOGGED], 0,
-            hdr->ts.tv_sec, hdr->ts.tv_usec, blob, hdr->caplen, message);
-
-        /* cast necessary because pcap_dump has a type matching the callback
-         * argument to pcap_loop()
-         * TODO don't block
-         */
-        pcap_dump ((u_char *) self->dumper, hdr, blob);
-        return TRUE;
-
-      case -2:
-        /* EOF; shouldn't happen since we waited for the FD to be readable */
-        g_set_error (error, G_IO_ERROR, G_IO_ERROR_CONNECTION_CLOSED,
-            "EOF when reading from dbus-monitor");
-        return FALSE;
+      /* EOF; shouldn't happen since we waited for the FD to be readable */
+      g_set_error (error, G_IO_ERROR, G_IO_ERROR_CONNECTION_CLOSED,
+          "EOF when reading from dbus-monitor");
+      return FALSE;
+    }
+  else
+    {
+      g_signal_emit (self, signals[SIG_MESSAGE_LOGGED], 0,
+          hdr->ts.tv_sec, hdr->ts.tv_usec, blob, hdr->caplen, message);
 
-      default:
-        g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
-            "Error %i reading dbus-monitor stream: %s",
-            ret, pcap_geterr (self->pcap_in));
-        return FALSE;
+      /* cast necessary because pcap_dump has a type matching the callback
+       * argument to pcap_loop()
+       * TODO don't block
+       */
+      pcap_dump ((u_char *) self->dumper, hdr, blob);
+      return TRUE;
     }
 }
 
@@ -834,7 +817,7 @@ cancellable_cancelled_cb (GCancellable *cancellable,
   /* Closes the stream; should cause dbus-monitor to quit in due course when it
    * tries to write to the other end of the pipe.
    */
-  g_clear_pointer (&self->pcap_in, pcap_close);
+  bustle_pcap_reader_close (self->reader);
 
   /* And try to terminate it immediately. */
   send_sigint (self);