Intrinsic functions implemented

git-svn-id: http://picoc.googlecode.com/svn/trunk@25 21eae674-98b7-11dd-bd71-f92a316d2d60

Makefile

@@ -3,7 +3,7 @@ CFLAGS=-Wall -g
 LIBS=-lm
 
 TARGET	= picoc
-SRCS	= picoc.c table.c str.c parse.c lex.c
+SRCS	= picoc.c table.c str.c parse.c lex.c intrinsic.c
 OBJS	:= $(SRCS:%.c=%.o)
 
 all: $(TARGET)

hello.c

@@ -1,6 +1,6 @@
 void fred()
 {
-    default
+    sayhello();
 }
 
 fred();

intrinsic.c

@@ -0,0 +1,62 @@
+#include <stdio.h>
+#include <string.h>
+#include "picoc.h"
+
+Str IntrinsicFilename = { 9, "intrinsic" };
+
+void IntrinsicPrintf(void)
+{
+    printf("IntrinsicPrintf\n");
+}
+
+void IntrinsicSayHello(void)
+{
+    printf("Hello\n");
+}
+
+struct IntrinsicFunction
+{
+    void (*Func)(void);
+    const char *Prototype;
+} Intrinsics[] =
+{
+    { IntrinsicSayHello,    "void sayhello()" },    /* -1 */
+    { IntrinsicPrintf,      "void printf()" },      /* -2 */
+};
+
+void IntrinsicInit(struct Table *GlobalTable)
+{
+    struct Value FuncVal;
+    struct LexState Lexer;
+    Str Source;
+    int Count;
+    union AnyValue Identifier;
+    enum ValueType Typ;
+    
+    FuncVal.Typ = TypeFunction;
+    for (Count = 0; Count < sizeof(Intrinsics) / sizeof(struct IntrinsicFunction); Count++)
+    {
+        Source.Str = Intrinsics[Count].Prototype;
+        Source.Len = strlen(Source.Str);
+        LexInit(&Lexer, &Source, &IntrinsicFilename, Count+1);
+        ParseType(&Lexer, &Typ);
+        LexGetToken(&Lexer, &Identifier);
+        FuncVal.Val.Integer = -1 - Count;
+        TableSet(GlobalTable, &Identifier.String, &FuncVal);
+    }
+}
+
+void IntrinsicGetLexer(struct LexState *Lexer, int IntrinsicId)
+{
+    Lexer->Line = -IntrinsicId;
+    Lexer->Pos = Intrinsics[-1-IntrinsicId].Prototype;
+    Lexer->End = Lexer->Pos + strlen(Lexer->Pos);
+    Lexer->FileName = &IntrinsicFilename;
+}
+
+void IntrinsicCall(struct LexState *Lexer, struct Value *Result, enum ValueType ReturnType, int IntrinsicId)
+{
+    Intrinsics[-1-IntrinsicId].Func();
+    Result->Typ = TypeVoid;
+}
+

parse.c

@@ -31,6 +31,7 @@ int ParseArguments(struct LexState *Lexer, int RunIt);
 void ParseInit()
 {
     TableInit(&GlobalTable, &GlobalHashTable[0], GLOBAL_TABLE_SIZE);
+    IntrinsicInit(&GlobalTable);
 }
 
 /* define a variable */
@@ -43,7 +44,7 @@ void VariableDefine(struct LexState *Lexer, const Str *Ident, struct Value *Init
 /* get the value of a variable. must be defined */
 void VariableGet(struct LexState *Lexer, Str *Ident, struct Value *Val, struct Value **LVal)
 {
-    if (!TableGet(&Stack[StackUsed-1].LocalTable, Ident, LVal))
+    if (StackUsed == 0 || !TableGet(&Stack[StackUsed-1].LocalTable, Ident, LVal))
     {
         if (!TableGet(&GlobalTable, Ident, LVal))
             ProgramFail(Lexer, "'%S' is undefined", Ident);
@@ -150,16 +151,25 @@ void ParseFunctionCall(struct LexState *Lexer, struct Value *Result, Str *FuncNa
             ProgramFail(Lexer, "not a function - can't call");
             
         StackFrameAdd(Lexer);
-        FuncLexer = FunctionStore[Result->Val.Integer];
+        if (Result->Val.Integer >= 0)
+            FuncLexer = FunctionStore[Result->Val.Integer];
+        else
+            IntrinsicGetLexer(&FuncLexer, Result->Val.Integer);
+
         ParseType(&FuncLexer, &ReturnType);             /* return type */
         Result->Typ = TypeVoid;
         LexGetPlainToken(&FuncLexer);                   /* function name again */
         ParseParameterList(Lexer, &FuncLexer, TRUE);    /* parameters */
-        if (LexPeekPlainToken(&FuncLexer) != TokenLeftBrace || !ParseStatement(&FuncLexer, TRUE))
-            ProgramFail(&FuncLexer, "function body expected");
+        if (Result->Val.Integer >= 0)
+        {
+            if (LexPeekPlainToken(&FuncLexer) != TokenLeftBrace || !ParseStatement(&FuncLexer, TRUE))
+                ProgramFail(&FuncLexer, "function body expected");
         
-        if (ReturnType != Result->Typ)
-            ProgramFail(&FuncLexer, "bad return value");
+            if (ReturnType != Result->Typ)
+                ProgramFail(&FuncLexer, "bad return value");
+        }
+        else
+            IntrinsicCall(Lexer, Result, ReturnType, Result->Val.Integer);
     }
 }
 

picoc.h

@@ -159,6 +159,8 @@ struct StackFrame
     struct TableEntry LocalHashTable[LOCAL_TABLE_SIZE];
 };
 
+/* globals */
+extern struct Table GlobalTable;
 
 /* str.c */
 void StrToC(char *Dest, int DestSize, const Str *Source);
@@ -188,6 +190,12 @@ enum LexToken LexPeekPlainToken(struct LexState *Lexer);
 /* parse.c */
 void ParseInit(void);
 void Parse(const Str *FileName, const Str *Source, int RunIt);
+int ParseType(struct LexState *Lexer, enum ValueType *Typ);
+
+/* intrinsic.c */
+void IntrinsicInit(struct Table *GlobalTable);
+void IntrinsicGetLexer(struct LexState *Lexer, int IntrinsicId);
+void IntrinsicCall(struct LexState *Lexer, struct Value *Result, enum ValueType ReturnType, int IntrinsicId);
 
 #endif /* PICOC_H */