From ffe81214b6bd99544d072545be47dac745786794 Mon Sep 17 00:00:00 2001
From: lonkaars <loek@pipeframe.xyz>
Date: Wed, 1 May 2024 17:20:19 +0200
Subject: add package fiddling + editorconfig + preprocessor options

---
 .editorconfig                   |  3 ++
 captures.txt                    |  9 ++++++
 src/frontend/qt_sdl/LocalMP.cpp | 67 ++++++++++++++++++++++++++++++-----------
 3 files changed, 62 insertions(+), 17 deletions(-)
 create mode 100644 .editorconfig
 create mode 100644 captures.txt

diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..3c77f6d
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,3 @@
+[*.{cpp,h}]
+indent_style = space
+indent_size = 4
diff --git a/captures.txt b/captures.txt
new file mode 100644
index 0000000..c3ed84f
--- /dev/null
+++ b/captures.txt
@@ -0,0 +1,9 @@
+historically significant pictochat captures
+
+melon_1714483602.pcap: first plain-text proof
+melon_1714557482.pcap: completely black message capture
+melon_1714564166.pcap: pattern v2 message
+
+melon_1714566548.pcap: 1 pixel vertical line, then 1 pixel horizontal line (check structure)
+
+
diff --git a/src/frontend/qt_sdl/LocalMP.cpp b/src/frontend/qt_sdl/LocalMP.cpp
index cc42706..b2e307e 100644
--- a/src/frontend/qt_sdl/LocalMP.cpp
+++ b/src/frontend/qt_sdl/LocalMP.cpp
@@ -16,6 +16,11 @@
     with melonDS. If not, see http://www.gnu.org/licenses/.
 */
 
+// VSR-specific experiments
+
+// #define VSR_MESSAGE_FIDDLING 1
+#define VSR_DUMP_MESSAGES 1
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -39,13 +44,18 @@
 #include "LocalMP.h"
 #include "Platform.h"
 
-#include <pcap/pcap.h>
-#include <time.h>
-#include <vector>
 #include <stdint.h>
 
+#ifdef VSR_DUMP_MESSAGES
+#include <pcap/pcap.h>
+#include <vector>
 pcap_dumper_t* dumper;
+#endif
+
+#ifdef VSR_MESSAGE_FIDDLING
+#include <time.h>
 unsigned long test_start = time(NULL);
+#endif
 
 using namespace melonDS;
 using namespace melonDS::Platform;
@@ -241,10 +251,12 @@ void SemReset(int num)
 
 bool Init()
 {
+#ifdef VSR_DUMP_MESSAGES
     pcap_t* handle = pcap_open_dead(DLT_USER0, 1 << 16);
     char filename[80];
     snprintf(filename, 79, "melon_%lu.pcap", time(NULL));
     dumper = pcap_dump_open(handle, filename);
+#endif
 
     MPQueue = new QSharedMemory("melonNIFI");
 
@@ -307,7 +319,9 @@ bool Init()
 
 void DeInit()
 {
+#ifdef VSR_DUMP_MESSAGES
     pcap_dump_close(dumper);
+#endif
 
     if (MPQueue)
     {
@@ -447,16 +461,18 @@ int SendPacketGeneric(u32 type, u8* packet, int len, u64 timestamp)
 
     u16 mask = header->ConnectedBitmask;
 
-    // // packet dropping test
-    // unsigned long now = time(NULL);
-    // static bool first = true;
-    // bool dropping = false;
-    // if (now - test_start > 20 && InstanceID == 0) {
-    //     if (first == true)
-    //         printf("[INSTANCE %d] started dropping packets!\n", InstanceID);
-    //     first = false;
-    //     dropping = true;
-    // }
+#ifdef VSR_MESSAGE_FIDDLING
+    // fiddle the packets after 20 seconds
+    unsigned long now = time(NULL);
+    static bool first = true;
+    bool fiddle = false;
+    if (now - test_start > 20 && InstanceID == 0) {
+        if (first == true)
+            printf("[INSTANCE %d] started fiddling!\n", InstanceID);
+        first = false;
+        fiddle = true;
+    }
+#endif
 
     // TODO: check if the FIFO is full!
 
@@ -467,30 +483,47 @@ int SendPacketGeneric(u32 type, u8* packet, int len, u64 timestamp)
     pktheader.Length = len;
     pktheader.Timestamp = timestamp;
 
+#ifdef VSR_DUMP_MESSAGES
     std::vector<uint8_t> buf;
+#endif
 
     type &= 0xFFFF;
     int nfifo = (type == 2) ? 1 : 0;
     // NOTE: this is the ni-fi packet header, altering this header in any way
     // seems to consistently trigger PACKET FIFO OVERFLOW errors
     FIFOWrite(nfifo, &pktheader, sizeof(pktheader));
+#ifdef VSR_DUMP_MESSAGES
     buf.insert(buf.end(), (uint8_t*) &pktheader, (uint8_t*) &pktheader + sizeof(pktheader));
+#endif
     if (len)
     {
-        // // replace packet content with random noise while dropping
-        // if (dropping)
-        //     for (size_t i = 0; i < len; i++)
-        //         packet[i] = rand();
+#ifdef VSR_MESSAGE_FIDDLING
+        if (fiddle && len == 0xde) {
+            // NOTE: packet indexes are after NIFI header!
+            packet[0x80] = 0x11;
+            packet[0x81] = 0x11;
+            packet[0x82] = 0x11;
+            packet[0x83] = 0x11;
+            packet[0x84] = 0x11;
+            packet[0x85] = 0x11;
+            packet[0x86] = 0x11;
+            packet[0x87] = 0x11;
+        }
+#endif
 
+#ifdef VSR_DUMP_MESSAGES
         buf.insert(buf.end(), (uint8_t*) packet, (uint8_t*) packet + len);
+#endif
         FIFOWrite(nfifo, packet, len);
     }
 
+#ifdef VSR_DUMP_MESSAGES
     struct pcap_pkthdr p;
     p.len = buf.size();
     p.caplen = buf.size();
     gettimeofday(&p.ts, NULL);
     pcap_dump((u_char*) dumper, &p, buf.data());
+#endif
 
     if (type == 1)
     {
-- 
cgit v1.2.3