Give a PacketDialog a Buffer and read directly into it and into its wtap_rec.

We may or may not be working on the currently-selected packet, so
there's no reason to use read into the capture_file's wtap_rec and
Buffer for the currently-selected packet.  We already have a wtap_rec of
our own, and we currently have a pointer to a raw packet data array that
we can replace with a Buffer of our own; just read into them.

Use wtap_rec_init() on the wtap_rec, rather than using its implicit
constructor - there's no guarantee that the initial values of the
structure members, as defined by C (and C++), are what we want.

Use wtap_rec_cleanup() in the destructor; it might do more than the
implied destructor (which does nothing).  wtap_rec and Buffer are C
structures, so they don't get C++ constructors and destructors - we have
to use the C ones, which are explicit functions.  I think there are
memory leaks that this fixes (packet comments and Buffer for the options
data, leaked when a PacketDialog window is closed).

Change-Id: Ica1d937fd00e4d2f5e4e2275bcd8edddb7a7921b
Reviewed-on: https://code.wireshark.org/review/32832
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

2 files changed, 13 insertions, 15 deletions

diff --git a/ui/qt/packet_dialog.cpp b/ui/qt/packet_dialog.cpp
index e35ec88885..ea917b1535 100644
--- a/ui/qt/packet_dialog.cpp
+++ b/ui/qt/packet_dialog.cpp
@@ -34,13 +34,15 @@ PacketDialog::PacketDialog(QWidget &parent, CaptureFile &cf, frame_data *fdata)
     WiresharkDialog(parent, cf),
     ui(new Ui::PacketDialog),
     proto_tree_(NULL),
-    byte_view_tab_(NULL),
-    rec_(wtap_rec()),
-    packet_data_(NULL)
+    byte_view_tab_(NULL)
 {
     ui->setupUi(this);
     loadGeometry(parent.width() * 4 / 5, parent.height() * 4 / 5);
     ui->hintLabel->setSmallText();
+
+    wtap_rec_init(&rec_);
+    ws_buffer_init(&buf_, 1514);
+
     edt_.session = NULL;
     edt_.tvb = NULL;
     edt_.tree = NULL;
@@ -49,23 +51,17 @@ PacketDialog::PacketDialog(QWidget &parent, CaptureFile &cf, frame_data *fdata)
 
     setWindowSubtitle(tr("Packet %1").arg(fdata->num));
 
-    if (!cf_read_record(cap_file_.capFile(), fdata)) {
+    if (!cf_read_record_r(cap_file_.capFile(), fdata, &rec_, &buf_)) {
         reject();
         return;
     }
 
-    rec_ = cap_file_.capFile()->rec;
-
-#ifndef __clang_analyzer__
-    packet_data_ = (guint8 *) g_memdup(ws_buffer_start_ptr(&(cap_file_.capFile()->buf)), fdata->cap_len);
-#endif
-
-    /* proto tree, visible. We need a proto tree if there's custom columns */
+    /* proto tree, visible. We need a proto tree if there are custom columns */
     epan_dissect_init(&edt_, cap_file_.capFile()->epan, TRUE, TRUE);
     col_custom_prime_edt(&edt_, &(cap_file_.capFile()->cinfo));
 
     epan_dissect_run(&edt_, cap_file_.capFile()->cd_t, &rec_,
-                     frame_tvbuff_new(&cap_file_.capFile()->provider, fdata, packet_data_),
+                     frame_tvbuff_new_buffer(&cap_file_.capFile()->provider, fdata, &buf_),
                      fdata, &(cap_file_.capFile()->cinfo));
     epan_dissect_fill_in_columns(&edt_, TRUE, TRUE);
 
@@ -108,7 +104,8 @@ PacketDialog::~PacketDialog()
 {
     delete ui;
     epan_dissect_cleanup(&edt_);
-    g_free(packet_data_);
+    wtap_rec_cleanup(&rec_);
+    ws_buffer_free(&buf_);
 }
 
 void PacketDialog::captureFileClosing()
diff --git a/ui/qt/packet_dialog.h b/ui/qt/packet_dialog.h
index 7beb1ff92a..d4bf898d0f 100644
--- a/ui/qt/packet_dialog.h
+++ b/ui/qt/packet_dialog.h
@@ -14,6 +14,7 @@
 
 #include "epan/epan_dissect.h"
 #include "wiretap/wtap.h"
+#include "wsutil/buffer.h"
 
 #include <ui/qt/utils/field_information.h>
 
@@ -44,9 +45,9 @@ private:
     QString col_info_;
     ProtoTree *proto_tree_;
     ByteViewTab *byte_view_tab_;
-    epan_dissect_t edt_;
     wtap_rec rec_;
-    guint8 *packet_data_;
+    Buffer buf_;
+    epan_dissect_t edt_;
 };
 
 #endif // PACKET_DIALOG_H