Fix the snapshot length part of the "same interface?" check.

Fix a typo - compare for unequal snapshot lengths, not equal snapshot
lengths.

Also, move the debug messages about checks right above the checks.

Change-Id: If6f5e125f05f3788b63e9f75d98f55e27830870b
Reviewed-on: https://code.wireshark.org/review/16470
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 24 insertions, 12 deletions

diff --git a/wiretap/merge.c b/wiretap/merge.c
index ea3f9a6dd5..7df0f2ba7b 100644
--- a/wiretap/merge.c
+++ b/wiretap/merge.c
@@ -440,24 +440,34 @@ is_duplicate_idb(const wtap_block_t idb1, const wtap_block_t idb2)
     merge_debug("merge::is_duplicate_idb() called");
     merge_debug("idb1_mand->wtap_encap == idb2_mand->wtap_encap: %s",
                  (idb1_mand->wtap_encap == idb2_mand->wtap_encap) ? "TRUE":"FALSE");
-    merge_debug("idb1_mand->time_units_per_second == idb2_mand->time_units_per_second: %s",
-                 (idb1_mand->time_units_per_second == idb2_mand->time_units_per_second) ? "TRUE":"FALSE");
-    merge_debug("idb1_mand->tsprecision == idb2_mand->tsprecision: %s",
-                 (idb1_mand->tsprecision == idb2_mand->tsprecision) ? "TRUE":"FALSE");
+    if (idb1_mand->wtap_encap != idb2_mand->wtap_encap) {
+        /* Clearly not the same interface. */
+        merge_debug("merge::is_duplicate_idb() returning FALSE");
+        return FALSE;
+    }
+
     merge_debug("idb1_mand->link_type == idb2_mand->link_type: %s",
                  (idb1_mand->link_type == idb2_mand->link_type) ? "TRUE":"FALSE");
-    merge_debug("idb1_mand->snap_len == idb2_mand->snap_len: %s",
-                 (idb1_mand->snap_len == idb2_mand->snap_len) ? "TRUE":"FALSE");
-
-    if (idb1_mand->wtap_encap != idb2_mand->wtap_encap ||
-        idb1_mand->link_type != idb2_mand->link_type) {
+    if (idb1_mand->link_type != idb2_mand->link_type) {
         /* Clearly not the same interface. */
         merge_debug("merge::is_duplicate_idb() returning FALSE");
         return FALSE;
     }
 
-    if (idb1_mand->time_units_per_second != idb2_mand->time_units_per_second ||
-        idb1_mand->tsprecision != idb2_mand->tsprecision) {
+    merge_debug("idb1_mand->time_units_per_second == idb2_mand->time_units_per_second: %s",
+                 (idb1_mand->time_units_per_second == idb2_mand->time_units_per_second) ? "TRUE":"FALSE");
+    if (idb1_mand->time_units_per_second != idb2_mand->time_units_per_second) {
+        /*
+         * Probably not the same interface, and we can't combine them
+         * in any case.
+         */
+        merge_debug("merge::is_duplicate_idb() returning FALSE");
+        return FALSE;
+    }
+
+    merge_debug("idb1_mand->tsprecision == idb2_mand->tsprecision: %s",
+                 (idb1_mand->tsprecision == idb2_mand->tsprecision) ? "TRUE":"FALSE");
+    if (idb1_mand->tsprecision != idb2_mand->tsprecision) {
         /*
          * Probably not the same interface, and we can't combine them
          * in any case.
@@ -467,7 +477,9 @@ is_duplicate_idb(const wtap_block_t idb1, const wtap_block_t idb2)
     }
 
     /* XXX: should snaplen not be compared? */
-    if (idb1_mand->snap_len == idb2_mand->snap_len) {
+    merge_debug("idb1_mand->snap_len == idb2_mand->snap_len: %s",
+                 (idb1_mand->snap_len == idb2_mand->snap_len) ? "TRUE":"FALSE");
+    if (idb1_mand->snap_len != idb2_mand->snap_len) {
         merge_debug("merge::is_duplicate_idb() returning FALSE");
         return FALSE;
     }