fix: coverity warnings (#3168)

* fix: uninitialized peer_atom field

* fix: silence inaccurate open-files-test warning

* fix: assertion-is-always-true

asserting unsigned val is >= 0

* fix: unnecessary nullptr check

* fix: nullptr dereference warning

gtk/FaviconCache.cc

@@ -94,10 +94,7 @@ bool favicon_web_done_idle_cb(std::unique_ptr<favicon_data> fav)
     }
 
     // Not released into the next web request, means we're done trying (even if `pixbuf` is still invalid)
-    if (fav != nullptr)
-    {
-        fav->func(pixbuf);
-    }
+    fav->func(pixbuf);
 
     return false;
 }

libtransmission/handshake.cc

@@ -704,7 +704,7 @@ static ReadState readPeerId(tr_handshake* handshake, struct evbuffer* inbuf)
     // if we've somehow connected to ourselves, don't keep the connection
     auto const hash = tr_peerIoGetTorrentHash(handshake->io);
     auto* const tor = hash ? handshake->session->torrents().get(*hash) : nullptr;
-    bool const connected_to_self = peer_id == tr_torrentGetPeerId(tor);
+    bool const connected_to_self = tor != nullptr && peer_id == tr_torrentGetPeerId(tor);
 
     return tr_handshakeDone(handshake, !connected_to_self);
 }

libtransmission/peer-mgr.cc

@@ -229,7 +229,7 @@ struct peer_atom
     time_t lastConnectionAttemptAt = {};
     time_t lastConnectionAt = {};
 
-    tr_peer* peer; /* will be nullptr if not connected */
+    tr_peer* peer = nullptr; // will be nullptr if not connected
 
     uint8_t const fromFirst; /* where the peer was first found */
     uint8_t fromBest; /* the "best" value of where the peer has been found */
@@ -2308,7 +2308,6 @@ static void removePeer(tr_peer* peer)
     --s->stats.peer_from_count[atom->fromFirst];
 
     TR_ASSERT(s->stats.peer_count == s->peerCount());
-    TR_ASSERT(s->stats.peer_from_count[atom->fromFirst] >= 0);
 
     delete peer;
 }

tests/libtransmission/open-files-test.cc

@@ -42,8 +42,8 @@ TEST_F(OpenFilesTest, getOpensIfNotCached)
     auto buf = std::array<char, std::size(Contents) + 1>{};
     auto bytes_read = uint64_t{};
     EXPECT_TRUE(tr_sys_file_read_at(*fd, std::data(buf), std::size(Contents), 0, &bytes_read));
-    buf[bytes_read] = '\0';
-    EXPECT_EQ(Contents, (char*)std::data(buf));
+    auto const contents = std::string_view{ std::data(buf), static_cast<size_t>(bytes_read) };
+    EXPECT_EQ(Contents, contents);
 }
 
 TEST_F(OpenFilesTest, getCacheSucceedsIfCached)