SpiderScript! (with a sample script)

[tpg/acess2.git] / Usermode / Libraries / libspiderscript.so_src / lex.c

diff --git a/Usermode/Libraries/libspiderscript.so_src/lex.c b/Usermode/Libraries/libspiderscript.so_src/lex.c
index 6badd45..25a7aa7 100644 (file)
--- a/Usermode/Libraries/libspiderscript.so_src/lex.c
+++ b/Usermode/Libraries/libspiderscript.so_src/lex.c
@@ -1,14 +1,22 @@
 /*
- * Acess2 init
+ * SpiderScript
  * - Script Lexer
  */
 #include "tokens.h"
 #include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#define USE_SCOPE_CHAR 0
+
+#define DEBUG  0
+
+#define ARRAY_SIZE(x)  ((sizeof(x))/(sizeof((x)[0])))
 
 // === PROTOTYPES ===
  int   is_ident(char ch);
- int   isdigit(char ch);
- int   isspace(char ch);
+ int   isdigit(int ch);
+ int   isspace(int ch);
  int   GetToken(tParser *File);
 
 // === CONSTANTS ===
@@ -17,8 +25,12 @@ const struct {
        const char      *Name;
 } csaReservedWords[] = {
        {TOK_RWD_FUNCTION, "function"},
-       {TOK_RWD_INTEGER, "integer"},
-       {TOK_RWD_REAL, "string"}
+       {TOK_RWD_RETURN, "return"},
+       {TOK_RWD_VOID, "void"},
+       {TOK_RWD_OBJECT, "Object"},
+       {TOK_RWD_INTEGER, "Integer"},
+       {TOK_RWD_REAL, "Real"},
+       {TOK_RWD_STRING, "String"}
 };
 
 // === CODE ===
@@ -31,19 +43,43 @@ int GetToken(tParser *File)
         int    ret;
        
        if( File->NextToken != -1 ) {
+               // Save Last
+               File->LastToken = File->Token;
+               File->LastTokenStr = File->TokenStr;
+               File->LastTokenLen = File->TokenLen;
+               File->LastLine = File->CurLine;
+               // Restore Next
                File->Token = File->NextToken;
                File->TokenStr = File->NextTokenStr;
                File->TokenLen = File->NextTokenLen;
+               File->CurLine = File->NextLine;
+               // Set State
+               File->CurPos = File->TokenStr + File->TokenLen;
                File->NextToken = -1;
+               {
+                       char    buf[ File->TokenLen + 1];
+                       memcpy(buf, File->TokenStr, File->TokenLen);
+                       buf[File->TokenLen] = 0;
+                       #if DEBUG
+                       printf(" GetToken: FAST Return %i (%i long) (%s)\n", File->Token, File->TokenLen, buf);
+                       #endif
+               }
                return File->Token;
        }
        
+       //printf("  GetToken: File=%p, File->CurPos = %p\n", File, File->CurPos);
+       
        // Clear whitespace (including comments)
        for( ;; )
        {
                // Whitespace
                while( isspace( *File->CurPos ) )
+               {
+                       //printf("whitespace 0x%x, line = %i\n", *File->CurPos, File->CurLine);
+                       if( *File->CurPos == '\n' )
+                               File->CurLine ++;
                        File->CurPos ++;
+               }
                
                // # Line Comments
                if( *File->CurPos == '#' ) {
@@ -61,9 +97,13 @@ int GetToken(tParser *File)
                
                // C-Style Block Comments
                if( *File->CurPos == '/' && File->CurPos[1] == '*' ) {
-                       File->CurPos += 2;
+                       File->CurPos += 2;      // Eat the '/*'
                        while( *File->CurPos && !(File->CurPos[-1] == '*' && *File->CurPos == '/') )
+                       {
+                               if( *File->CurPos == '\n' )     File->CurLine ++;
                                File->CurPos ++;
+                       }
+                       File->CurPos ++;        // Eat the '/'
                        continue ;
                }
                
@@ -75,11 +115,14 @@ int GetToken(tParser *File)
        File->LastToken = File->Token;
        File->LastTokenStr = File->TokenStr;
        File->LastTokenLen = File->TokenLen;
+       File->LastLine = File->CurLine;
        
        // Read token
        File->TokenStr = File->CurPos;
        switch( *File->CurPos++ )
        {
+       case '\0':      ret = TOK_EOF;  break;
+       
        // Operations
        case '/':       ret = TOK_DIV;  break;
        case '*':       ret = TOK_MUL;  break;
@@ -95,9 +138,9 @@ int GetToken(tParser *File)
        
        // Strings
        case '"':
-               File->TokenStr ++;
                while( *File->CurPos && !(*File->CurPos == '"' && *File->CurPos != '\\') )
                        File->CurPos ++;
+               File->CurPos ++;
                ret = TOK_STR;
                break;
        
@@ -111,7 +154,10 @@ int GetToken(tParser *File)
        
        // Core symbols
        case ';':       ret = TOK_SEMICOLON;    break;
+       case ',':       ret = TOK_COMMA;        break;
+       #if USE_SCOPE_CHAR
        case '.':       ret = TOK_SCOPE;        break;
+       #endif
        
        // Equals
        case '=':
@@ -128,7 +174,6 @@ int GetToken(tParser *File)
        // Variables
        // \$[0-9]+ or \$[_a-zA-Z][_a-zA-Z0-9]*
        case '$':
-               File->TokenStr ++;
                // Numeric Variable
                if( isdigit( *File->CurPos ) ) {
                        while( isdigit(*File->CurPos) )
@@ -136,7 +181,7 @@ int GetToken(tParser *File)
                }
                // Ident Variable
                else {
-                       while( is_ident(*File->CurPos) )
+                       while( is_ident(*File->CurPos) || isdigit(*File->CurPos) )
                                File->CurPos ++;
                }
                ret = TOK_VARIABLE;
@@ -144,6 +189,7 @@ int GetToken(tParser *File)
        
        // Default (Numbers and Identifiers)
        default:
+               File->CurPos --;
                // Numbers
                if( isdigit(*File->CurPos) )
                {
@@ -160,16 +206,49 @@ int GetToken(tParser *File)
                        while( is_ident(*File->CurPos) || isdigit(*File->CurPos) )
                                File->CurPos ++;
                        
+                       // This is set later too, but we use it below
+                       File->TokenLen = File->CurPos - File->TokenStr;
                        ret = TOK_IDENT;
+                       
+                       // Check if it's a reserved word
+                       {
+                               char    buf[File->TokenLen + 1];
+                                int    i;
+                               memcpy(buf, File->TokenStr, File->TokenLen);
+                               buf[File->TokenLen] = 0;
+                               for( i = 0; i < ARRAY_SIZE(csaReservedWords); i ++ )
+                               {
+                                       if(strcmp(csaReservedWords[i].Name, buf) == 0) {
+                                               ret = csaReservedWords[i].Value;
+                                               break ;
+                                       }
+                               }
+                       }
+                       // If there's no match, just keep ret as TOK_IDENT
+                       
                        break;
                }
                // Syntax Error
-               ret = 0;
+               ret = TOK_INVAL;
+               
+               fprintf(stderr, "Syntax Error: Unknown symbol '%c'\n", *File->CurPos);
+               longjmp(File->JmpTarget, 1);
+               
                break;
        }
        // Return
        File->Token = ret;
        File->TokenLen = File->CurPos - File->TokenStr;
+       
+       #if DEBUG
+       {
+               char    buf[ File->TokenLen + 1];
+               memcpy(buf, File->TokenStr, File->TokenLen);
+               buf[File->TokenLen] = 0;
+               //printf("  GetToken: File->CurPos = %p\n", File->CurPos);
+               printf(" GetToken: Return %i (%i long) (%s)\n", ret, File->TokenLen, buf);
+       }
+       #endif
        return ret;
 }
 
@@ -177,13 +256,20 @@ void PutBack(tParser *File)
 {
        if( File->LastToken == -1 ) {
                // ERROR:
+               fprintf(stderr, "INTERNAL ERROR: Putback when LastToken==-1\n");
+               longjmp( File->JmpTarget, -1 );
                return ;
        }
+       #if DEBUG
+       printf(" PutBack: Was on %i\n", File->Token);
+       #endif
        // Save
+       File->NextLine = File->CurLine;
        File->NextToken = File->Token;
        File->NextTokenStr = File->TokenStr;
        File->NextTokenLen = File->TokenLen;
        // Restore
+       File->CurLine = File->LastLine;
        File->Token = File->LastToken;
        File->TokenStr = File->LastTokenStr;
        File->TokenLen = File->LastTokenLen;
@@ -194,6 +280,7 @@ void PutBack(tParser *File)
 
 int LookAhead(tParser *File)
 {
+       // TODO: Should I save the entire state here?
         int    ret = GetToken(File);
        PutBack(File);
        return ret;
@@ -207,19 +294,22 @@ int LookAhead(tParser *File)
 int is_ident(char ch)
 {
        if('a' <= ch && ch <= 'z')      return 1;
-       if('Z' <= ch && ch <= 'Z')      return 1;
+       if('A' <= ch && ch <= 'Z')      return 1;
        if(ch == '_')   return 1;
+       #if !USE_SCOPE_CHAR
+       if(ch == '.')   return 1;
+       #endif
        if(ch < 0)      return 1;
        return 0;
 }
 
-int isdigit(char ch)
+int isdigit(int ch)
 {
        if('0' <= ch && ch <= '9')      return 1;
        return 0;
 }
 
-int isspace(char ch)
+int isspace(int ch)
 {
        if(' ' == ch)   return 1;
        if('\t' == ch)  return 1;