From 7c29048397e8791d96cfc51cbb5aaf7f4c69f392 Mon Sep 17 00:00:00 2001
From: Maxwell Jeffress <maxwelljeffress@proton.me>
Date: Sat, 4 Jul 2026 17:53:14 +1000
Subject: [PATCH] Begin work on reworked extern instruction

---
 README.md                          |  8 ++++
 include/ground.h                   |  8 +++-
 src/Bytecode/Instruction/execute.c | 28 ++++++++++++++
 src/New/Bytecode.c                 | 59 +++++++++++++++++++++++++++++-
 4 files changed, 100 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index cb27d2a..0a9ef07 100644
--- a/README.md
+++ b/README.md
@@ -18,3 +18,11 @@ You may need to run `ldconfig` or reboot to update your ld cache.
 ## Bytecode Format
 
 Under the hood, Ground uses a bytecode format to store things.
+
+## Changes from old CGround
+
+### `extern` instruction
+
+`extern` no longer loads a dynamic library from /usr/lib/ground, it is now used to detail a system shared library to open.
+
+Format: `extern "libName" "symbolName" !functionName -returnType -argType...`
diff --git a/include/ground.h b/include/ground.h
index 53324e0..98d1092 100644
--- a/include/ground.h
+++ b/include/ground.h
@@ -126,7 +126,8 @@ struct GroundError {
 enum GroundTypeType {
     GroundType_Int, GroundType_Double, GroundType_Char, GroundType_Bool,
     GroundType_String, GroundType_List,
-    GroundType_Function, GroundType_Struct, GroundType_Object
+    GroundType_Function, GroundType_Struct, GroundType_Object,
+    GroundType_CoreType,
 };
 
 struct GroundType {
@@ -152,6 +153,8 @@ struct GroundValue {
         GroundFunction Function;
         GroundStruct   Struct;
         GroundObject   Object;
+
+        enum GroundTypeType CoreType;
     } as;
 
     GroundType type;
@@ -313,6 +316,9 @@ struct GroundBytecodeValue {
         GroundBytecodeFunction Function;
         GroundBytecodeStruct   Struct;
         GroundBytecodeObject   Object;
+
+        // For core types 
+        enum GroundTypeType CoreType;
     } as;
 
     GroundType type;
diff --git a/src/Bytecode/Instruction/execute.c b/src/Bytecode/Instruction/execute.c
index c64d09a..1166cd8 100644
--- a/src/Bytecode/Instruction/execute.c
+++ b/src/Bytecode/Instruction/execute.c
@@ -822,6 +822,34 @@ struct GroundExecutionResult _GroundBytecodeInstructionExecute(GroundBytecodeIns
         return CONTINUE;
     }
     EXTERN: {
+        // extern "libfile.so" "symbolName" !fnName -returnType -argType...
+        void* handle = Ground.FFI.openSharedObject(HEAP_GET(heap, instruction->args.at[0])->as.String.cstr);
+        if (Ground.Flags.error) {
+            return CONTINUE;
+        }
+        void* function = Ground.FFI.getFunction(handle, HEAP_GET(heap, instruction->args.at[0])->as.String.cstr);
+        if (Ground.Flags.error) {
+            return CONTINUE;
+        }
+        GroundSize argsSize = instruction->args.len - 4; // subtract 4 for libfile, symbol name, fn name, return type
+        GroundBytecodeFunction bf = {
+            .isNativeFunction = true,
+            .closure = NULL,
+            .program.native = handle,
+            .args = {
+                .at = malloc(sizeof(GroundFunctionArg) * argsSize),
+                .capacity = argsSize,
+                .count = argsSize
+            },
+        };
+        if (bf.args.at == NULL) {
+            Ground.Log.Error("malloc failed in Ground.Bytecode.Instruction.execute");
+            Ground.Flags.error = true;
+            return CONTINUE;
+        }
+        for (size_t i = 0; i < argsSize; i++) {
+
+        }
         return CONTINUE;
     }
     CREATELABEL: {
diff --git a/src/New/Bytecode.c b/src/New/Bytecode.c
index c8733d2..470e9f3 100644
--- a/src/New/Bytecode.c
+++ b/src/New/Bytecode.c
@@ -78,10 +78,10 @@ static inline void doLabels(GroundProgram* program, GroundState* state) {
 static inline GroundSize doOffsets(GroundProgram* gp, GroundState* state, GroundBytecodeProgram* gbp) {
     GroundSize size = 0;
 
-    // Add size of state
+    // Add size of state and assign offsets to pre-existing variables
     GroundVariable *s, *tmp;
     HASH_ITER(hh, state->variables, s, tmp) {
-        size++;
+        s->_offset = size++;
     }
 
     for (GroundSize i = 0; i < gp->len; i++) {
@@ -175,6 +175,61 @@ GroundBytecode _GroundNewBytecode(GroundProgram* program, GroundState* state) {
         return bytecode;
     }
 
+    // Add core types to state 
+    for (unsigned int i = 0; i < (unsigned int)GroundType_Object; i++) {
+        GroundVariable* var = malloc(sizeof(GroundVariable));
+        if (var == NULL) {
+            Ground.Log.Error("malloc failed in Ground.New.Bytecode");
+            Ground.Flags.error = true;
+            return bytecode;
+        }
+        var->value = (GroundValue) {
+            .type = {GroundType_CoreType},
+            .as.CoreType = (enum GroundTypeType) i
+        };
+
+        switch ((enum GroundTypeType) i) {
+            case GroundType_Int: {
+                sprintf(var->name, "int");
+                break;
+            }
+            case GroundType_Double: {
+                sprintf(var->name, "double");
+                break;
+            }
+            case GroundType_Char: {
+                sprintf(var->name, "char");
+                break;
+            }
+            case GroundType_Bool: {
+                sprintf(var->name, "bool");
+                break;
+            }
+            case GroundType_String: {
+                sprintf(var->name, "string");
+                break;
+            }
+            case GroundType_List: {
+                sprintf(var->name, "list");
+                break;
+            }
+            case GroundType_Function: {
+                sprintf(var->name, "function");
+                break;
+            }
+            case GroundType_Struct: {
+                sprintf(var->name, "struct");
+                break;
+            }
+            default: break; // unreachable (in theory)
+        }
+
+        HASH_ADD_STR(state->variables, name, var);
+
+    }
+
+    state->_size += (unsigned int)GroundType_Object + 1;
+
     // Precompute some really cool stuff
     doLabels(program, state);
     if (Ground.Flags.error) return bytecode;