Labels and control flow

README.md

@@ -22,9 +22,9 @@ Progress marker:
     - [x] Values
     - [x] References
 - [ ] Interpreter
-    - [ ] Labels
+    - [x] Labels
     - [ ] Console I/O
-    - [ ] Control flow
+    - [x] Control flow
     - [ ] Data
         - [ ] Variable creation
         - [ ] Variable access

src/interpreter.c

@@ -6,6 +6,8 @@
 
 int currentInstruction = 0;
 
+GroundLabel* labels = NULL;
+
 void runtimeError(GroundRuntimeError error, char* what, GroundInstruction* where, int whereLine) {
     printf("Ground runtime error:\n  ErrorType: ");
     switch (error) {
@@ -41,11 +43,37 @@ void runtimeError(GroundRuntimeError error, char* what, GroundInstruction* where
     exit(1);
 }
 
+void addLabel(GroundLabel **head, const char *id, int data) {
+    GroundLabel* item = malloc(sizeof(GroundLabel));
+    snprintf(item->id, MAX_ID_LEN, "%s", id);
+    item->lineNum = data;
+    HASH_ADD_STR(*head, id, item);
+}
+
+GroundLabel* findLabel(GroundLabel* head, const char *id) {
+    GroundLabel *item;
+    HASH_FIND_STR(head, id, item);
+    return item;
+}
+
+void deleteLabel(GroundLabel** head, GroundLabel *item) {
+    HASH_DEL(*head, item);
+    free(item);
+}
+
+void delete_all(GroundLabel **head) {
+    GroundLabel *current, *tmp;
+    HASH_ITER(hh, *head, current, tmp) {
+        HASH_DEL(*head, current);
+        free(current);
+    }
+}
+
 void interpretGroundProgram(GroundProgram* in) {
     // Preprocess all labels
     for (int i = 0; i < in->size; i++) {
         if (in->instructions[i].type == CREATELABEL) {
-            // labelHashmap.addLabel()
+            addLabel(&labels, in->instructions[i].args.args[0].value.refName, i);
         }
     }
     while (currentInstruction < in->size) {
@@ -61,6 +89,54 @@ void interpretGroundInstruction(GroundInstruction* in) {
         case CREATELABEL: {
             break;
         }
+        case IF: {
+            if (in->args.length < 2) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 2 arguments", in, currentInstruction);
+            }
+            if (in->args.length > 2) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 2 arguments", in, currentInstruction);
+            }
+            if (in->args.args[0].type != VALUE && in->args.args[0].value.value.type != BOOL) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a bool for arg 0", in, currentInstruction);
+            }
+            if (in->args.args[0].type != LINEREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a LineRef for arg 1", in, currentInstruction);
+            }
+
+            if (in->args.args[0].value.value.data.boolVal) {
+                GroundLabel* label = findLabel(labels, in->args.args[1].value.refName);
+                if (label) {
+                    currentInstruction = label->lineNum;
+                } else {
+                    runtimeError(UNKNOWN_LABEL, NULL, in, currentInstruction);
+                }
+            }
+        }
+        case JUMP: {
+            if (in->args.length < 1) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 1 argument", in, currentInstruction);
+            }
+            if (in->args.length > 1) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 1 argument", in, currentInstruction);
+            }
+            if (in->args.args[0].type != LINEREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a LineRef for arg 1", in, currentInstruction);
+            }
+
+            GroundLabel* label = findLabel(labels, in->args.args[0].value.refName);
+            if (label) {
+                currentInstruction = label->lineNum;
+            } else {
+                runtimeError(UNKNOWN_LABEL, NULL, in, currentInstruction);
+            }
+        }
+        case END: {
+            if (in->args.length < 1) {
+                exit(0);
+            } else {
+            }
+            break;
+        }
         case PRINT: {
             if (in->args.length < 1) {
                 runtimeError(TOO_FEW_ARGS, NULL, in, currentInstruction);
@@ -82,13 +158,6 @@ void interpretGroundInstruction(GroundInstruction* in) {
             printf("\n");
             break;
         }
-        case END: {
-            if (in->args.length < 1) {
-                exit(0);
-            } else {
-            }
-            break;
-        }
         default: {
             runtimeError(FIXME, "Currently unimplemented instruction", in, currentInstruction);
         }

src/interpreter.h

@@ -1,16 +1,19 @@
 #ifndef INTERPRETER_H
 #define INTERPRETER_H
+#define MAX_ID_LEN 64
 
 #include "types.h"
 #include "parser.h"
 #include "include/uthash.h"
 
 typedef enum GroundRuntimeError {
-    ARG_TYPE_MISMATCH, TOO_FEW_ARGS, TOO_MANY_ARGS, FIXME 
+    ARG_TYPE_MISMATCH, TOO_FEW_ARGS, TOO_MANY_ARGS, UNKNOWN_LABEL, FIXME 
 } GroundRuntimeError;
 
 typedef struct GroundLabel {
-    
+    char id[MAX_ID_LEN];
+    int lineNum;
+    UT_hash_handle hh;
 } GroundLabel;
 
 void interpretGroundProgram(GroundProgram* in);

tests/simple.grnd

@@ -1 +1,3 @@
-print
+@myLabel
+println "dingus"
+jump %myLabel