From cf955ef3fbf4e01703ea7498aca6337124c4a4bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dominik=20Madar=C3=A1sz?= <zaklaus@outlook.com>
Date: Tue, 4 May 2021 01:57:19 +0200
Subject: [PATCH] additional packing helpers

---
 code/apps/client/source/network.c    | 10 ++++++++++
 code/apps/server/source/main.c       |  2 --
 code/common/packets/packet.c         |  3 +++
 code/common/packets/packet_utils.h   |  6 +++++-
 code/common/packets/pkt_01_welcome.c | 19 +++++++++----------
 5 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/code/apps/client/source/network.c b/code/apps/client/source/network.c
index 59058f5..fbebdfd 100644
--- a/code/apps/client/source/network.c
+++ b/code/apps/client/source/network.c
@@ -8,6 +8,7 @@
 #include "librg.h"
 
 #include "network.h"
+#include "packets/packet.h"
 
 #define NETWORK_UPDATE_DELAY 0.100
 
@@ -108,6 +109,15 @@ int32_t network_client_tick() {
             } break;
 
             case ENET_EVENT_TYPE_RECEIVE: {
+                pkt_header header = {0};
+                uint32_t ok = pkt_header_decode(&header, event.packet->data, event.packet->dataLength);
+                
+                if (ok && header.ok) {
+                    pkt_handlers[header.id].handler(&header);
+                } else {
+                    zpl_printf("[INFO] Server sent us an unsupported packet.\n");
+                }
+                
                 /* handle a newly received event */
                 // librg_world_read(
                 //     world,
diff --git a/code/apps/server/source/main.c b/code/apps/server/source/main.c
index 4c96890..eea0433 100644
--- a/code/apps/server/source/main.c
+++ b/code/apps/server/source/main.c
@@ -99,5 +99,3 @@ int main(int argc, char** argv) {
 void platform_shutdown(void) {
     is_running = false;
 }
-
-#include "packets/pkt_01_welcome.c"
diff --git a/code/common/packets/packet.c b/code/common/packets/packet.c
index e2f20ad..149bc6c 100644
--- a/code/common/packets/packet.c
+++ b/code/common/packets/packet.c
@@ -42,6 +42,7 @@ int32_t pkt_unpack_struct(cw_unpack_context *uc, pkt_desc *desc, void *raw_blob,
     for (pkt_desc *field = desc; field->type != 0; ++field) {
         cw_unpack_next(uc);
         if (uc->item.type != field->type) return -1; // unexpected field
+        if (blob + field->offset + field->size >= blob + blob_size) return -1; // field does not fit
         switch (field->type) {
             case CWP_ITEM_POSITIVE_INTEGER: {
                 zpl_memcopy(blob + field->offset, (uint8_t*)uc->item.as.u64, field->size);
@@ -55,3 +56,5 @@ int32_t pkt_unpack_struct(cw_unpack_context *uc, pkt_desc *desc, void *raw_blob,
     
     return 0;
 }
+
+#include "packets/pkt_01_welcome.c"
\ No newline at end of file
diff --git a/code/common/packets/packet_utils.h b/code/common/packets/packet_utils.h
index e0e27d3..01cc871 100644
--- a/code/common/packets/packet_utils.h
+++ b/code/common/packets/packet_utils.h
@@ -41,7 +41,7 @@ inline int32_t pkt_validate_eof_msg(cw_unpack_context *uc) {
 #endif
 
 #ifndef PKT_STRUCT_PTR
-#define PKT_STRUCT_PTR(a) (void*)a, (uint32_t)sizeof(*a)
+#define PKT_STRUCT_PTR(a) (void*)(a), (uint32_t)sizeof(*(a))
 #endif
 
 #ifndef PKT_FIELD
@@ -52,6 +52,10 @@ inline int32_t pkt_validate_eof_msg(cw_unpack_context *uc) {
 #define PKT_END .type = CWP_NOT_AN_ITEM
 #endif
 
+#ifndef PKT_IF
+#define PKT_IF(c) if (c < 0) return -1;
+#endif
+
 typedef struct pkt_desc {
     cwpack_item_types type;
     size_t offset;
diff --git a/code/common/packets/pkt_01_welcome.c b/code/common/packets/pkt_01_welcome.c
index f1cf755..17275e7 100644
--- a/code/common/packets/pkt_01_welcome.c
+++ b/code/common/packets/pkt_01_welcome.c
@@ -4,12 +4,7 @@
 
 #define PKT_01_WELCOME_ARGS 2
 
-pkt_desc pkt_01_welcome_desc[3] = {
-    { PKT_FIELD(CWP_ITEM_POSITIVE_INTEGER, pkt_01_welcome, chunk_size) },
-    { PKT_FIELD(CWP_ITEM_POSITIVE_INTEGER, pkt_01_welcome, chunk_amount) },
-    { PKT_END },
-};
-
+#ifdef SERVER
 size_t pkt_01_welcome_encode(pkt_01_welcome *table) {
     cw_pack_context pc = {0};
     pkt_pack_msg(&pc, PKT_01_WELCOME_ARGS);
@@ -19,7 +14,12 @@ size_t pkt_01_welcome_encode(pkt_01_welcome *table) {
 
     return pc.current - pc.start; /* length */
 }
-
+#else
+pkt_desc pkt_01_welcome_desc[3] = {
+    { PKT_FIELD(CWP_ITEM_POSITIVE_INTEGER, pkt_01_welcome, chunk_size) },
+    { PKT_FIELD(CWP_ITEM_POSITIVE_INTEGER, pkt_01_welcome, chunk_amount) },
+    { PKT_END },
+};
 int32_t pkt_01_welcome_decode(pkt_01_welcome *table, pkt_header *header) {
     cw_unpack_context uc = {0};
     pkt_unpack_msg(&uc, header, PKT_01_WELCOME_ARGS);
@@ -29,11 +29,10 @@ int32_t pkt_01_welcome_decode(pkt_01_welcome *table, pkt_header *header) {
 }
 
 int32_t pkt_01_welcome_handler(pkt_header *header) {
-#if 1
     pkt_01_welcome table;
-    pkt_01_welcome_decode(&table, header);
+    PKT_IF(pkt_01_welcome_decode(&table, header));
 
     zpl_printf("we received: chunk_size: %d and chunk_amount: %d\n", table.chunk_size, table.chunk_amount);
-#endif
     return 0;
 }
+#endif
\ No newline at end of file