Implemented do, while, and for

c02.c

@@ -37,6 +37,7 @@ void init()
   inpfil = srcfil;
   strcpy(inpnam, srcnam);
   alcvar = TRUE;
+  inblck = FALSE;
   nxtwrd[0] = 0;
   nxtptr = 0;
 }
@@ -45,7 +46,7 @@ void init()
 pword()
 {
   getwrd();
-  SCMNT(word);
+  ACMNT(word);
   DEBUG("Parsing Word '%s'\n", word);
   if (wordis("byte")) 
     pdecl(VTBYTE);   //Parse 'byte' declaration
@@ -88,17 +89,16 @@ void compile()
     //DEBUG("Checking next character '%c'\n", nxtchr);
     if (match(EOF)) 
       break;
+    else if (match('}'))
+      endblk(TRUE);  //End Multi-Line Program Block
     else if (match('#'))
-      pdrctv(); //Process Directive
+      pdrctv();      //Parse Directive
     else if (match('/')) 
-      skpcmt();
+      skpcmt();      //Skip Comment
     else if (isalph()) 
-      pword();
+      pword();       //Parse Word
     else
-	  {
+      ERROR("Unexpected character '%c'\n", nxtchr, EXIT_FAILURE);
-      printf("Unexpected character '%c'\n", nxtchr);	 
-		  exterr(EXIT_FAILURE);
-	  }
   }    
   epilog();
 }

common.h

@@ -8,7 +8,8 @@
 #define MAXDEF 255        //Maximum Number of Definitions
 #define VARLEN 6          //Maximum Variable Length
 #define MAXVAR 255        //Maximum Number of Variables
-#define DATASPC 2048      //Space to Allocate for 
+#define MAXFNS 16         //Maximum Functions in Stack
+#define DATASPC 2048      //Space to Allocate for Variable Data
 #define LABLEN 6          //Maximum Label Length
 #define LABFMT "L_%04d"   //Label Format
 #define LABSFX ":"        //Label Suffix

cond.c

@@ -41,16 +41,20 @@ int enccmp(char c)
  * Args: comparator - Encoded Comparison Operator     *
  * Uses: term - Term Being Compared Against           *
  *       label - Branch Target if Comparison is FALSE */
-void prccmp(int cmprtr) 
+void prccmp() 
 {
   DEBUG("Processing comparison operator %d\n", cmprtr);
+  DEBUG("Expression signedness is %d\n", expsgn);
   switch(cmprtr) {
+    case 0: // Raw Expression (Skip)
+      asmlin("BEQ", curlbl);
+      break;
     case 1: // = or ==
       asmlin("CMP", term);
       asmlin("BNE", curlbl);
       break;
     case 2: // <
-      if (cmpsgn) {
+      if (expsgn) {
         asmlin("CMP", term);
         asmlin("BPL", curlbl);
       }
@@ -60,7 +64,7 @@ void prccmp(int cmprtr)
       }
       break;
     case 3: // <= or =<
-      if (cmpsgn) {
+      if (expsgn) {
         asmlin("CMP", term);
         asmlin("BPL", curlbl);
         asmlin("BNE", curlbl);
@@ -72,7 +76,7 @@ void prccmp(int cmprtr)
       }
       break;
     case 4: // >
-      if (cmpsgn) {
+      if (expsgn) {
         asmlin("CMP", term);
         asmlin("BMI", curlbl);
         asmlin("BEQ", curlbl);
@@ -84,7 +88,7 @@ void prccmp(int cmprtr)
       }
       break;
     case 5: // >= or =>
-      if (cmpsgn) {
+      if (expsgn) {
         asmlin("CMP", term);
         asmlin("BMI", curlbl);
       }
@@ -97,6 +101,9 @@ void prccmp(int cmprtr)
       asmlin("CMP", term);
       asmlin("BEQ", curlbl);
       break;
+    case 7: // Raw Expression (Normal)
+      asmlin("BNE", curlbl);
+      break;
     default:
       printf("Unsupported comparison operator index %d\n", cmprtr);
       exterr(EXIT_FAILURE);
@@ -104,13 +111,13 @@ void prccmp(int cmprtr)
 }
 
 /* Parse Comparison Operator                      *
- * Sets: comparitor - Encoded Comparison Operator */
+ * Sets: cmprtr - Encoded Comparison Operator */
 int prscmp() 
 {
   cmpenc = enccmp(nxtchr);      //Encode Comparison Character
-  if (cmpenc == 0) 
-    expctd("comparison operator");
   cmprtr = cmpenc;              //Set Encoded Comparator 
+  if (cmprtr == 0)              //No Comparison
+    return;
   cmpenc = enccmp(nxtchr);      //Encode Next Comparison Character
   if (cmpenc != 0)
     cmprtr = cmprtr | cmpenc;   //Combine Encoded Comparator
@@ -120,15 +127,17 @@ int prscmp()
 
 /* Parse and Compile Conditional Expression     *
  * Condition = <expression> <comparator> <term> */
-void prscnd(char trmntr) 
+void prscnd(char trmntr, int revrse) 
 {
   DEBUG("Parsing condition\n", 0);
   prsxpr(0);
   skpspc();
   prscmp();
-  prstrm();
+  if (cmprtr)
+    prstrm();
+  cmprtr = cmprtr ^ revrse & 7;
+  prccmp();
   CCMNT(trmntr);
-  prccmp(cmprtr);
   expect(trmntr);
 }
 

cond.h

@@ -4,5 +4,5 @@
 
 int cmpsgn;  // Comparison contains signed operands
 
-void prscnd(char trmntr); //Parse Conditional Expression 
+void prscnd(char trmntr, int revrse); //Parse Conditional Expression 
 

expr.c

@@ -11,8 +11,16 @@
 #include "asm.h"
 #include "parse.h"
 #include "vars.h"
+#include "label.h"
 #include "expr.h"
 
+/* Set Expession Signedness */
+setsgn(int sgndns)
+{
+  expsgn = sgndns;
+  DEBUG("Set Expression Signedness to %d\n", expsgn);
+}
+
 /* Parse value (constant or identifier)  *
  * Sets: value - the value (as a string) *
  *       valtyp - value type           */
@@ -22,8 +30,11 @@ void prsval()
   //expdef();      //Check for and expand define -- BROKEN!
   if (iscpre())
     prscon(0xff); //Parse Constant
-  else if (isalph())
+  else if (isalph()) {
     prsvar();     //Parse Variable
+    DEBUG("Checking type of variable '%s'\n", value);
+    if (vartyp[lookup(value)] == VTBYTE) setsgn(TRUE);  
+  }
   else
     expctd("constant or variable");
   skpspc();
@@ -41,7 +52,7 @@ void prsidx()
   expect(']');
 }
 
-/* Parse term in expression            *
+/* Parse term in  expression            *
  * Sets: term - the term (as a string) * 
  *       trmtxt - type of term      */
 void prstrm()
@@ -62,39 +73,80 @@ void prstrm()
   skpspc();
 }
 
-/* Parse and Compile Pointer Dereference */
+/* Compile Address Reference */
-void prsadr(char dlmtr)
+void prcadr(char* symbol)
 {
-  prsvar();
-  DEBUG("Dereferencing variable '%s'\n", value);
-  ACMNT(value);
   strcpy(word,"#<");
-  strcat(word,value);
+  strcat(word,symbol);
   asmlin("LDX", word);
   strcpy(word,"#>");
-  strcat(word,value);
+  strcat(word,symbol);
   asmlin("LDY", word);
-  if (dlmtr) expect(dlmtr);
+} 
+
+/* Parse and Compile Address of Operator */
+void prsadr()
+{
+  prsvar();
+  DEBUG("Parsing address of variable '%s'\n", value);
+  ACMNT(value);
+  prcadr(value);  //Compile Address Reference
 }
 
-
+/* Parse and Create Anonymous String */
-/* Parse function call in first term of expression *
+void prsstr()
- * Function call may include term as an argument   */
-void prsxfn() 
 {
-  char fnname[255]; /*Function name*/ 
+  DEBUG("Parsing anonymous string\n", 0);
-  DEBUG("Processing expression function call '%s'...\n", term);
+  strcpy(tmplbl, curlbl);//Save Current Label
-  strcpy(fnname, term);
+  newlbl();              //Generate Label Name
+  strcpy(word, curlbl);  //and Use as Variable Name
+  value[0] = 0;          //Use Variable Size 0
+  setvar(VTCHAR);        //Set Variable Name, Type, and Size
+  prsdts();              //Parse Data String
+  setdat();              //Set Variable Data
+  varcnt++;              //Increment Variable Counter
+  prcadr(curlbl);        //Compile Address Reference
+  strcpy(curlbl, tmplbl);//Restore Current Label
+}
+
+/* Parse Additional Function Parameters */
+void prsfnp() 
+{
+  if (look(',')) {
+    if (look('&'))
+      prsadr();
+    else if (match('"'))
+      prsstr();
+    else {
+      prstrm();
+      asmlin("LDY", term);
+      if (look(',')) {
+        prsval();
+        asmlin("LDX", value);
+      }  
+    }
+  }
+}
+
+/* Parse function call */
+void prsfnc() 
+{
+  DEBUG("Processing Function Call '%s'...\n", term);
+  if (fnscnt >= MAXFNS)
+    ERROR("Maximum Function Call Depth Exceeded", 0, EXIT_FAILURE);
+  strcpy(fnstck[fnscnt++], term);
   skpchr(); //skip open paren
   CCMNT('(');
   if (look('&'))
-    prsadr(0);
+    prsadr();
+  else if (match('"'))
+    prsstr();
   else if (isvpre()) {
-    prstrm();
+    prsxpr(0);
-    asmlin("LDA", term);
+    prsfnp();
-  }
+  }  
   expect(')');
-  asmlin("JSR", fnname);
+  asmlin("JSR", fnstck[--fnscnt]);
   skpspc();
 }
 
@@ -107,7 +159,7 @@ void prsftm()
   strcpy(term, value);
   trmtxt = valtyp;
   if (trmtxt == FUNCTION) {
-     prsxfn(); //Parse Expression Function
+     prsfnc(); //Parse Expression Function
      return;
   }
   if (trmtxt == ARRAY) {
@@ -153,8 +205,12 @@ void prsxpr(char trmntr)
 {
   DEBUG("Parsing expression\n", 0);
   skpspc();
-  if (match('-')) 
+  setsgn(FALSE); //Default Expression to Unsigned
-    asmlin("LDA", "#$00");  //Handle Unary Minus
+  if (match('-')) {
+    DEBUG("Processing unary minus", 0);
+    asmlin("LDA", "#$00");  //Handle Unary Minus  
+    setsgn(TRUE); //Expression is Signed
+  } 
   else 
     prsftm(); //Parse First Term
   while (isoper())

expr.h

@@ -5,7 +5,13 @@
 char term[255];   /*Term parsed from equation*/
 int  trmtxt;      /*Term Type*/
 
+int expsgn; //Expression Contains Signed Term
+
+char fnstck[MAXFNS][VARLEN+1];   //Function Call Stack
+int  fnscnt;                     //Number of Functions in Stack
+
 void prsidx();            //Parse Array Index
 void prstrm();            //Parse Term in Expression
 void prsxpr(char trmntr); //Parse Expression
 
+

label.c

@@ -13,6 +13,29 @@
 #include "parse.h"
 #include "label.h"
 
+/* Find Last Label of Specified Type *
+ * Args: lbtype: Label type          *
+ * Sets: tmplbl - Label name         *
+ * Returns: Index into label table   *
+ *          (-1 if not found)        */
+int lstlbl(int lbtype)
+{
+  int i;
+  DEBUG("Searching for label type %d\n", lbtype);
+  for (i = lblcnt - 1; i>-1; i--) 
+    if (lbltyp[i] == lbtype) break;
+  DEBUG("Search produced label index %d\n", i);
+  if (i>=0) 
+    strcpy(tmplbl, lblnam[i]);
+  return i;
+}
+
+/* Set Block Flag for Last Label */
+void setblk(int blkflg)
+{
+  lblblk[lblcnt-1] = blkflg;
+}
+
 /* Set label for next line of *
  * Assembly Language Code     *
  * to word                    */
@@ -21,8 +44,8 @@ void setlbl(char *lblset)
   DEBUG("Setting Label '%s''\n", lblset);
   if (strlen(lblasm) > 0)
     asmlin("",""); //Emit Block End Label on it's own line
-  if (strlen(word) > LABLEN) 
+  if (strlen(lblset) > LABLEN) 
-    ERROR("Label '%s' exceeds maximum size", word, EXIT_FAILURE);
+    ERROR("Label '%s' exceeds maximum size\n", word, EXIT_FAILURE);
   strcpy(lblasm, lblset);
 }
 
@@ -35,27 +58,35 @@ void prslbl()
 }
 
 /* generate new label */
-void newlbl(int lbtype) 
+void newlbl() 
 {
   sprintf(curlbl, LABFMT, lblnxt++);
   DEBUG("Generated new label '%s'\n", curlbl);
-  strcpy(lblnam[lblcnt++], curlbl);
-  lbltyp[lblcnt] = lbtype;
 }
 
-/* set label to emit on next line and remove from stack */
+/* Pop Label from Stack and Emit on Next Line */
-void lbllin() 
+int poplbl() 
 {
   int lbtype = lbltyp[--lblcnt];
-  if (lbtype == 1) {
+  DEBUG("Popped label type %d\n", lbtype);
-      DEBUG("Ending Loop at Level %d'\n", lblcnt);
+  if (lbtype == LTLOOP)
-      strcpy(endlbl, lblnam[lblcnt]);  //Save End of Loop Label
+    asmlin("JMP", lblnam[lblcnt--]); //Jump to Beginning of Loop   
-      asmlin("JMP", lblnam[--lblcnt]); //Jump to Beginning of Loop   
+  if (lbtype == LTDO)
-      setlbl(endlbl);                  //Set End of Loop Label
+    strcpy(loplbl, lblnam[lblcnt]);
-  }
   else
     setlbl(lblnam[lblcnt]);
- DEBUG("Set label '%s' to emit on next line\n", lblasm);
+  inblck = lblblk[lblcnt-1];
+  return lbtype;
 }
 
+/* Push Label onto Stack        *
+ * Args: lbltyp - Label type    *
+ * Uses: curlbl - Label to push */
+void pshlbl(int lbtype) 
+{
+  strcpy(lblnam[lblcnt], curlbl);
+  lbltyp[lblcnt] = lbtype;
+  lblblk[lblcnt++] = FALSE;
+  DEBUG("Pushed label '%s' onto stack\n", curlbl);
+}
 

label.h

@@ -2,18 +2,25 @@
  * C02 Label Parsing, Generation, and Lookup Routines *
  ******************************************************/
 
+int  inblck;                       //Multiline Block Flag
+
 char curlbl[LABLEN+1];             //Most recently generated label
-char endlbl[LABLEN+1];             //Label at end of block
+char endlbl[LABLEN+1];             //End Label
+char loplbl[LABLEN+1];             //Skip Increment Label
+char skplbl[LABLEN+1];             //Skip Increment Label
+char tmplbl[LABLEN+1];             //Temporary Label
 char lblnam[MAXLAB+1][LABLEN+1];   //Label Name Table
 int  lbltyp[MAXLAB+1];             //Label Type
+int  lblblk[MAXLAB+1];             //Label Ends Program Block
 int  lblcnt;                       //Number of Labels in stack
 int  lblnxt;                       //Sequence of next label to be generated
 char lbltmp[LABLEN+1];             //Label Temporary Storage
 
-enum ltypes {LTIF, LTLOOP, LTEND}; //Label Types
+enum ltypes {LTIF, LTLOOP, LTEND, LTDO}; //Label Types
 
-void prslbl();     //Parse Label From Code
+int lstlbl(int lbtype); //Find Last Label of Specified Type
-void newlbl();     //Generate New Block Label
+void prslbl();          //Parse Label From Code
-void lbllin();     //Pull Last Label and Emit on Next Line
+void newlbl();          //Generate New Block Label
-void setlbl();     //Emit word as Label on Next Line
+int poplbl();          //Pull Last Label and Emit on Next Line
+void setlbl();          //Emit word as Label on Next Line
 

parse.c

@@ -15,22 +15,22 @@
 char opstr[2]; //Operator as a String
 
 /* Various tests against nxtchr */
-int match(char c) {return (nxtchr == c);}
+int match(char c) {return TF(nxtchr == c);}
-int inbtwn(char mn, char mx) {return nxtchr >= mn && nxtchr <= mx;}
+int inbtwn(char mn, char mx) {return TF(nxtchr >= mn && nxtchr <= mx);}
 int isprnt() {return isprint(nxtchr);}
 int isalph() {return isalpha(nxtchr);}
 int isanum() {return isalnum(nxtchr);}
 int isdec()  {return inbtwn('0', '9');}
-int ishexd() {return isdec() || inbtwn('A', 'Z');}
+int ishexd() {return TF(isdec() || inbtwn('A', 'Z'));}
 int isbin()  {return inbtwn('0', '1');}
-int isnl()   {return match('\n') || match('\r');}
+int isnl()   {return TF(match('\n') || match('\r'));}
 int isspc()  {return isspace(nxtchr);}
-int isnpre() {return isdec() || match('$') || match('%');}
+int isnpre() {return TF(isdec() || match('$') || match('%'));}
 int isapos() {return match('\'');}
-int iscpre() {return isnpre() || isapos();}
+int iscpre() {return TF(isnpre() || isapos());}
-int isvpre() {return isalph() || iscpre();}
+int isvpre() {return TF(isalph() || iscpre());}
-int isoper() {return (strchr("+-&|^", nxtchr)) ? TRUE : FALSE;}
+int isoper() {return TF(strchr("+-&|^", nxtchr));}
-int ispopr() {return (strchr("+-<>", nxtchr)) ? TRUE : FALSE;}
+int ispopr() {return TF(strchr("+-<>", nxtchr));}
 
 /* if Word is s then return TRUE else return FALSE*/
 int wordis(char *s)
@@ -182,29 +182,37 @@ void expdef()
 
 char escape(char c) 
 {
+  DEBUG("Escaping character '%c'\n", c);
   switch (c) {
     case 'r': return 0x0d;
     default: return c;
   }
 }
 
-void get_string() {
+/* Get String */
-  char str_del, tmp_char;
+
-  int wrdlen = 0, esc_next = FALSE;
+void getstr() {
+  char strdel, tmpchr;
+  int wrdlen = 0, escnxt = FALSE;
   DEBUG("Parsing string\n", 0);
-  str_del = getnxt();
+  strdel = getnxt();  //Get String Delimiter
-  while(!match(str_del)) {
+  CCMNT(strdel);
-    if (esc_next)
+  while(match(strdel) == escnxt) {
+    CCMNT(nxtchr);
+    if (escnxt) {
       word[wrdlen++] = escape(getnxt());
+      escnxt = FALSE;    
+    }
     else {
       if (match('\\')) 
-        esc_next = TRUE;
+        escnxt = TRUE;
       else
         word[wrdlen++] = nxtchr;
       skpchr();
     }  
   }
-  skpchr();
+  skpchr(); //Skip End Delimiter
+  CCMNT(strdel);
   word[wrdlen++] = 0;
 }
 
@@ -343,15 +351,18 @@ int prsnum(int maxval)
  *       valtyp - value type (CONSTANT)   */
 void prscon(int maxval) 
 {
-  int constant = prsnum(maxval);
+  cnstnt = prsnum(maxval);
   valtyp = CONSTANT;
   if (maxval > 255)
-    sprintf(value, "#$%04X", constant);
+    sprintf(value, "#$%04X", cnstnt);
   else
-    sprintf(value, "#$%02X", constant);
+    sprintf(value, "#$%02X", cnstnt);
   DEBUG("Generated constant '%s'\n", value);
 }
-int get_vartyp()
+
+
+/* Get Value Type */
+int gettyp()
 {
   if (match('(')) return FUNCTION;
   else if (match('[')) return ARRAY;
@@ -364,7 +375,7 @@ int get_vartyp()
 void prsvar() 
 {
   getwrd();
-  valtyp = get_vartyp();
+  valtyp = gettyp();
   if (valtyp != FUNCTION) chksym(word);
   strcpy(value, word);
   DEBUG("Parsed variable '%s'\n", value);

parse.h

@@ -2,6 +2,8 @@
  * C02 Input File Parsing Routines   *
  *************************************/
 
+#define TF(x) (x) ? TRUE : FALSE;
+
 enum trmtxts {CONSTANT, VARIABLE, ARRAY, FUNCTION};
 enum etypes {ETDEF, ETMAC};      //Definition Types
 
@@ -11,6 +13,7 @@ int  nxtptr;          //Pointer to next character in nxtwrd
 char value[LINELEN];  //Term parsed from equation
 int  valtyp;          //Value Type
 char oper;            //Arithmetic or Bitwise Operator
+int cnstnt;           //Value of Parsed Constant
 
 char defnam[MAXDEF+1][VARLEN+1]; //Definition Name Table
 char deftxt[MAXDEF+1][DEFLEN+1]; //Definition Text Table

stmnt.c

@@ -11,73 +11,17 @@
 #include "asm.h"
 #include "parse.h"
 #include "vars.h"
-#include "expr.h"
 #include "label.h"
+#include "expr.h"
 #include "stmnt.h"
 
-/* parse and compile if statement */
-void pif() {
-  DEBUG("Parsing IF statement '%c'\n", nxtchr);
-  expect('(');
-  newlbl(LTIF);
-  prscnd(')');  //Parse Conditional Expession
-}
 
-/* parse and compile else statement */
+/* Process Assignment */
-void pelse() {
+void prcasn(char trmntr)
-  DEBUG("Parsing ELSE statement '%c'\n", nxtchr);
-  strcpy(lbltmp, lblasm);
-  lblasm[0] = 0;
-  newlbl(LTIF);
-  asmlin("JMP", curlbl);
-  strcpy(lblasm, lbltmp);
-}
-
-/* parse and compile for statement */
-void pfor() {
-  ERROR("Unsupported statement FOR encountered",0, EXIT_FAILURE);  
-}
-
-/* parse and compile if statement */
-void pgoto() {
-  DEBUG("Parsing GOTO statement\n", 0);
-  getwrd();
-  ACMNT(word);
-  asmlin("JMP", word);
-  expect(';');  
-}
-
-/* parse and compile if statement */
-void pretrn() {
-  DEBUG("Parsing RETURN statement\n", 0);
-  if (!look(';'))
-    prsxpr(';');
-  asmlin("RTS", "");
-}
-
-/* parse and compile while statement */
-void pwhile() {
-  DEBUG("Parsing WHILE statement '%c'\n", nxtchr);
-  expect('(');
-  newlbl(LTLOOP);         //create Loop Label
-  setlbl(curlbl);
-  newlbl(LTEND);          //Create End Label
-  prscnd(')');            //Parse Conditional Expession
-}
-
-/* generate unimplemented statement error */
-void punimp() {
-  ERROR("Unimplemented statement '%s' encountered", word, EXIT_FAILURE);  
-}
-
-
-/* Parse and compile assignment */
-void prsasn()
 {
-  DEBUG("Parsing assignment of variable '%s''\n", asnvar);
+  DEBUG("Processing assignment of variable '%s'\n", asnvar);
-  skpchr(); //skip equals sign
+  expect('=');
-  ACMNT("=");
+  prsxpr(trmntr);
-  prsxpr(';');
   if (strlen(asnidx)) {
     asmlin("LDX", asnidx);
     strcat(asnvar,",X");
@@ -108,50 +52,22 @@ void prcpop() {
 }
 
 /* Parse Post Operator */
-void prspop() {
+void prspop(char trmntr) {
   oper = getnxt();
   CCMNT(oper); CCMNT(oper);
   DEBUG("Checking for post operation '%c'\n", oper);
   if (nxtchr == oper) {
     skpchr();
     prcpop();  //Process Post-Op
-    expect(';');
+    expect(trmntr);
   }
   else
     expctd("post operator"); 
 }
 
-/* Parse function call in first expression  */
+/* Process Variable at Beginning of Statement */
-void prsfnc() 
+void prcvar(char trmntr)
 {
-  char fnname[255]; /*Function name*/ 
-  DEBUG("Processing function call '%s'...\n", term);
-  strcpy(fnname, word);
-  skpchr(); //skip open paren
-  CCMNT('(');
-  skpspc();
-  if (match(')'))    //if no arguments 
-    skpchr();       //  skip close paren
-  else {               //otherwise
-    if (look('&')) {
-      prsadr(')');
-    }
-    else
-      prsxpr(')');  //parse expression
-  }
-  asmlin("JSR", fnname);
-  expect(';');
-}
-
-/* parse and compile identifier (variable or function call) */
-void prssym()
-{
-  DEBUG("Parsing Identifier %s\n", word);
-  valtyp = get_vartyp();
-  if (valtyp == FUNCTION) {
-    prsfnc();  //Parse Function Call
-    return;
-  }
   chksym(word);
   strcpy(asnvar, word);  //sav variable to assign to
   if (valtyp == ARRAY) {
@@ -161,15 +77,180 @@ void prssym()
   else
     asnidx[0] = 0;
   if (ispopr(nxtchr))
-    prspop();  //Parse Post Operator
+    prspop(trmntr);  //Parse Post Operator
   else
-  {
+    prcasn(trmntr);
-    skpspc();
+}
-    if (match('='))
+
-      prsasn();      //Parse Assignment
+/* Begin Program Block */
-    else
+void bgnblk()
-      expctd("=");
+{
-  }
+  DEBUG("Begining program block\n", 0);
+  inblck = look('{');  
+  setblk(inblck);
+}
+
+/* Parse and Compile and Assignment */
+void prsasn(char trmntr) 
+{
+  getwrd();               //Get Variable to be Assigned
+  ACMNT(word);
+  prcvar(trmntr);
+}
+
+/* parse and compile 'break'/'continue' statement */
+void pbrcnt(int lbtype) {
+  DEBUG("Parsing BREAK/CONTINUE statement\n", 0);
+  if (lstlbl(lbtype) < 0)
+    ERROR("Break/continue statement outside of loop\n", 0, EXIT_FAILURE);
+  DEBUG("Found Label '%s'\n", tmplbl);
+  asmlin("JMP", tmplbl);
+  expect(';'); 
+}
+
+/* parse and compile 'do' statement */
+void pdo() {
+  DEBUG("Parsing DO statement '%c'\n", nxtchr);
+  newlbl();                //Create Do Loop Label
+  pshlbl(LTDO);            //Push onto Stack
+  setlbl(curlbl);          //Set Label to Emit on Next Line
+  bgnblk();                //Check For and Begin Block
+}
+
+/* parse and compile 'while' after 'do' statement */
+void pdowhl() {
+  DEBUG("Parsing WHILE after DO '%c'\n", nxtchr);
+  getwrd();                //Check for While
+  ACMNT(word);
+  if (!wordis("while"))
+     expctd("while statement");
+  expect('(');
+  newlbl();                //Create Skip Label
+  prscnd(')', FALSE);      //Parse Conditional Expession
+  asmlin("JMP", loplbl);   //Emit Jump to Beginning of Loop
+  setlbl(curlbl);          //and Set Label to Emit on Next Line
+  expect(';');             //Check for End of Statement
+}
+
+
+/* parse and compile for statement */
+void pfor() {
+  DEBUG("Parsing FOR statement '%c'\n", nxtchr);
+  expect('(');
+  prsasn(';');            //Process Initial Assignment     
+  newlbl();               //Create Temporary Label
+  setlbl(curlbl);         //Set to Emit on Next Line
+  strcpy(tmplbl, curlbl); //and Save it
+  newlbl();               //Create End Label
+  pshlbl(LTEND);          //and Push onto Stack
+  strcpy(endlbl, curlbl); //and Save it
+  newlbl();               //Create Loop Label
+  strcpy(loplbl, curlbl); //and Save it
+  pshlbl(LTLOOP);         //and Push onto Stack
+  newlbl();               //Create Skip Increment Label
+  strcpy(skplbl, curlbl); //and Save it
+  prscnd(';', TRUE);     //Parse Conditional Expession
+  asmlin("JMP", endlbl);  //Jump over Increment
+  setlbl(loplbl);         //Set to Emit on Next Line
+  prsasn(')');            //Parse Increment Assignment
+  asmlin("JMP", tmplbl);  //Jump to Conditional
+  setlbl(skplbl);         //Emit Label at Start of Loop  
+  bgnblk();               //Check For and Begin Block
+}
+
+/* parse and compile if statement */
+void pif() {
+  DEBUG("Parsing IF statement '%c'\n", nxtchr);
+  expect('(');
+  newlbl();            //Create New Label
+  pshlbl(LTIF);        //Push Onto Stack
+  prscnd(')', FALSE);  //Parse Conditional Expession
+  bgnblk();            //Check For and Begin Block
+}
+
+/* parse and compile else statement */
+void pelse() {
+  DEBUG("Parsing ELSE statement '%c'\n", nxtchr);
+  strcpy(lbltmp, lblasm);
+  lblasm[0] = 0;
+  newlbl();      //Create New Label
+  pshlbl(LTIF);  //Push Onto Stack
+  asmlin("JMP", curlbl);
+  strcpy(lblasm, lbltmp);
+  bgnblk();                //Check For and Begin Block
+}
+
+/* parse and compile if statement */
+void pgoto() {
+  DEBUG("Parsing GOTO statement\n", 0);
+  getwrd();
+  ACMNT(word);
+  asmlin("JMP", word);
+  expect(';');  
+}
+
+/* parse and compile if statement */
+void pretrn() {
+  DEBUG("Parsing RETURN statement\n", 0);
+  if (!look(';'))
+    prsxpr(';');
+  asmlin("RTS", "");
+}
+
+/* parse and compile while statement */
+void pwhile() {
+  DEBUG("Parsing WHILE statement '%c'\n", nxtchr);
+  expect('(');
+  newlbl();                //Create End Label
+  pshlbl(LTEND);           //Push onto Stack
+  strcpy(endlbl, curlbl);  //and Save it
+  newlbl();                //create Loop Label
+  setlbl(curlbl);          //Set to Emit on Next Line
+  pshlbl(LTLOOP);          //Push onto Stack
+  newlbl();                //Create Conditional Skip Label
+  prscnd(')', TRUE);       //Parse Conditional Expession
+  asmlin("JMP", endlbl);   //Emit Jump to End of Loop
+  setlbl(curlbl);          //and Set Label to Emit on Next Line
+  bgnblk();                //Check For and Begin Block
+}
+
+/* generate unimplemented statement error */
+void punimp() {
+  ERROR("Unimplemented statement '%s' encountered\n", word, EXIT_FAILURE);  
+}
+
+
+/* Parse Function Call as Statement */
+void prsfns()
+{
+  strcpy(term, word);  //Copy Function Name
+  prsfnc();            //Parse Function Call
+  expect(';');
+  return;
+}
+
+/* parse and compile identifier (variable or function call) */
+void prssym()
+{
+  DEBUG("Parsing Identifier %s\n", word);
+  valtyp = gettyp();
+  if (valtyp == FUNCTION)
+    prsfns();  //Parse Statement Function Call
+  else
+    prcvar(';'); //Parse Assignment
+}
+
+/* End Program Block                    *
+ * Args: blkflg: End of Multiline Block */
+void endblk(int blkflg)
+{
+  DEBUG("Ending program block with flag %d\n", blkflg);
+  skpchr();  //Skip '}';
+  DEBUG("Found inblck set to %d\n", inblck);
+  if (inblck != blkflg)
+    ERROR("Encountered '}' without matching '{'\n",0,EXIT_FAILURE);
+  if (poplbl() == LTDO)
+    pdowhl(); //Parse While at End of Do Loop
 }
 
 /* parse and compile program statement */
@@ -180,6 +261,10 @@ void pstmnt()
     prslbl();  //Parse Label
     return;
   }
+  if (wordis("do")) {
+    pdo();
+    return;
+  }
   if (wordis("if")) {
     pif();
     return;
@@ -193,17 +278,22 @@ void pstmnt()
     return;  
   }
   if (wordis("for")) {
-    punimp();
+    pfor();
     return;  
   }
+  else if (wordis("break"))
+    pbrcnt(LTEND);
+  else if (wordis("continue"))
+    pbrcnt(LTLOOP);
   else if (wordis("goto"))
     pgoto();
   else if (wordis("return"))
     pretrn();
   else
     prssym();
-  if (lblcnt) {
+  if (lblcnt && !inblck) {
-    lbllin();
+  if (poplbl() == LTDO)
+    pdowhl(); //Parse While at End of Do Loop
   }
 }
 

stmnt.h

@@ -2,7 +2,8 @@
  * C02 Statement Compiling Routines *
  ************************************/
 
-char asnvar[VARLEN+1];         /*Assigned Variable Name*/
+char asnvar[VARLEN+1];         //Assigned Variable Name
-char asnidx[VARLEN+1] ;         /*Assigned Variable Index*/
+char asnidx[VARLEN+1] ;        //Assigned Variable Index
-
 
+void endblk();                 //End Program Block
+void pstmnt();                 //Parse and Compile Program Statement

vars.c

@@ -45,7 +45,6 @@ void chksym(char *name)
     ERROR("Undeclared variable '%s' encountered\n", word, EXIT_FAILURE);
 }
 
-
 /* Check for Array specifier and get size *
  * Sets: value - array size (as string)   *
  *               "" if not an array       */
@@ -76,36 +75,64 @@ void prsdtc()
 void prsdts()
 {
   dtype = DTSTR;
-  get_string();
+  getstr();
   strcpy(value, word);
   DEBUG("Parsed Data String '%s'\n", value);
 }
 
-/* Parse and store variable data    *
+/* Store variable data              *
+ * Uses: value    - Data to store   *
  * Sets: datvar[] - Variable Data   *
  *       datlen[] - Data Length     */
+void setdat()
+{
+  int i;
+  if (dtype == DTBYTE) {
+    DEBUG("Setting variable data to '%d'\n", cnstnt);
+    dlen = 1;
+    datvar[dsize++] = cnstnt;
+  }
+  else {
+    DEBUG("Setting variable data to '%s'\n", value);
+    dlen = strlen(value);
+    for (i=0; i<dlen; i++) 
+      datvar[dsize++] = value[i];   
+  } 
+  datlen[varcnt] = dlen;
+  dattyp[varcnt] = dtype;  
+}
+
+/* Parse and store variable data */
 void prsdat()
 {
   DEBUG("Checking for variable data\n", 0);
-  int i;
   if (!look('=')) {
     datlen[varcnt] = 0;
     return;
   }
   skpspc();
   if (isnpre())
-    prsdtc(0xff);
+    prsdtc(0xff);   //Parse Data Constant
   else if (match('"'))
-    prsdts();
+    prsdts();       //Parse Data String
-  dlen = strlen(value);
+  else
-  datlen[varcnt] = dlen;
+    expctd("numeric or string constant");
-  dattyp[varcnt] = dtype;
+  setdat();   //Store Data Value
-  DEBUG("Setting variable data to '%s'\n", value);
-  for (i=0; i<dlen; i++) 
-    datvar[dsize++] = value[i]; 
 }
 
 /* Add Variable to Variable table *
+ * Uses: word - variable name     *
+ *       value - variable size    */
+void setvar(int t) 
+{
+  DEBUG("Adding variable '%s'\n", word);
+  strncpy(varnam[varcnt], word, VARLEN);
+  vartyp[varcnt] = t;
+  strncpy(varsiz[varcnt], value, 3);
+  DEBUG("Added at index %d\n", varcnt);
+}
+
+/* Parse and Compile Variable Declaration *
  * Uses: word - variable name     */
 void addvar(int t) 
 {
@@ -113,14 +140,10 @@ void addvar(int t)
     ERROR("Duplicate declaration of variable '%s\n", word,EXIT_FAILURE);
   if (t == VTVOID)
     ERROR("Illegal Variable Type\n", 0, EXIT_FAILURE);
-  DEBUG("Adding variable '%s'\n", word);
+  pvarsz();   //Check for Array Declaration and Get Size
-  strncpy(varnam[varcnt], word, VARLEN);
+  setvar(t);  //Add to Variable Table  
-  vartyp[varcnt] = t;
+  prsdat();   //Parse Variable Data
-  pvarsz();
+  varcnt++;   //Increment Variable Counter
-  strncpy(varsiz[varcnt], value, 3);
-  DEBUG("Added at index %d\n", varcnt);
-  prsdat(); //Parse Variable Data
-  varcnt++;
 }
 
 void addfnc()
@@ -155,7 +178,7 @@ void vardat(int i)
   value[0] = 0;
   for (j=0; j<datlen[i]; j++) {
     if (j) strcat(value,",");
-    sprintf(word, "$%02X", datvar[dlen++]);
+    sprintf(word, "$%hhX", datvar[dlen++]);
     strcat(value, word);  
   }
   if (dattyp[i] == DTSTR) strcat(value, ",$00");
@@ -191,10 +214,10 @@ void vartbl()
 void logvar()
 {
   int i;
-  fprintf(logfil, "\n%-31s %s %s\n", "Variable", "Type", "Size");
+  fprintf(logfil, "\n%-31s %s %s %s\n", "Variable", "Type", "Size", "Data");
   for (i=0; i<varcnt; i++)
   {
-    fprintf(logfil, "%-31s %4d %s\n", varnam[i], vartyp[i], varsiz[i]);
+    fprintf(logfil, "%-31s %4d %4s %1d-%d\n", varnam[i], vartyp[i], varsiz[i], dattyp[i], datlen[i]);
   }
 }
 

vars.h

@@ -8,6 +8,10 @@ char vartyp[MAXVAR+1];             //Variable Type
 char varsiz[MAXVAR+1][4];          //Variable Array
 int  varcnt;                       //Number of Variables in Table
 
+/*
+int varidx; //Index into Variable Table
+int vrtype; //Variable Type
+*/
 enum vtypes {VTVOID, VTBYTE, VTCHAR};    //Variable Types
 
 char datvar[DATASPC+1];            //Variable Data Storage
@@ -22,6 +26,9 @@ enum dtypes {DTBYTE, DTSTR};       //Variable Data Types
 int symdef(char *name);   //Is Variable defined (TRUE or FALSE)
 void chksym(char *name);  //Error if Variable not defined
 
-void pdecl(int t); //Parse Variable Declaration
+void prsdts();       //Parse Data String
+void setdat();       //Set Variable Data
+void setvar(int t);  //Set Variable Name and Size
+void pdecl(int t);   //Parse Variable Declaration
 
 void vartbl();      //Create Variable Table