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asm6.c
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/* History:
1.6
Prevent error overload by emitting 2 bytes when branch instructions fail to parse
Bugfix for negative numbers being parsed incorrectly after too many passes are made
Compatible with big-endian and 64-bit machines
-q (quiet mode) command line option added
Lots of miscellaneous code cleanup
1.51
Added extra INCBIN args
1.5
Added local labels
Added DL, DH directives
Added ERROR directive
Bugfix for ACC opcode type
1.4
Decided to start keeping a history.
Added some special handling of IFDEF in expandline()
Changed macro usage: no parentheses around arg list, and args must be comma separated.
*/
//todo - do NOT open source files in update mode, since we do not want to modify them in any way
//todo - don't open text files in binary mode
//todo - thoroughly verify operation on big-endian machine
//todo - avoid putting special values into pointers, like (char*)1
//todo - don't depend on platform supporting unaligned objects
//todo - make everything static
//todo - redundant parsing code is all over the place, try clean it up / consolidate
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stddef.h>
#include <ctype.h>
#include <stdarg.h>
#define VERSION "1.6"
#define addr firstlabel.value//'$' value
#define NOORIGIN -0x40000000//nice even number so aligning works before origin is defined
#define INITLISTSIZE 128//initial label list size
#define BUFFSIZE 8192//file buffer (inputbuff, outputbuff) size
#define WORDMAX 128 //used with getword()
#define LINEMAX 2048//plenty of room for nested equates
#define MAXPASSES 7//# of tries before giving up
#define IFNESTS 32//max nested IF levels
#define DEFAULTFILLER 0 //default fill value
#define LOCALCHAR '@'
static void* true_ptr = &true_ptr;
enum labeltypes {LABEL,VALUE,EQUATE,MACRO,RESERVED};
//LABEL: known address
//VALUE: defined with '='
//EQUATE: made with EQU
//MACRO: macro (duh)
//RESERVED: reserved word
typedef struct {
const char *name; //label name
// ptrdiff_t so it can hold function pointer on 64-bit machines
ptrdiff_t value; //PC (label), value (equate), param count (macro), funcptr (reserved)
char *line; //for macro or equate, also used to mark unknown label
//*next:text->*next:text->..
//for macros, the first <value> lines hold param names
//for opcodes (reserved), this holds opcode definitions, see initlabels
int type; //labeltypes enum (see above)
int used; //for EQU and MACRO recursion check
int pass; //when label was last defined
int scope; //where visible (0=global, nonzero=local)
void *link; //labels that share the same name (local labels) are chained together
} label;
label firstlabel={ //'$' label
"$",//*name
0,//value
(char*)&true_ptr,//*line
VALUE,//type
0,//used
0,//pass
0,//scope
0,//link
};
typedef unsigned char byte;
typedef void (*icfn)(label*,char**);
label *findlabel(char*);
void initlabels();
label *newlabel();
void getword(char*,char**,int);
int getvalue(char**);
int getoperator(char**);
int eval(char**,int);
label *getreserved(char**);
int getlabel(char*,char**);
void processline(char*,char*,int);
void listline(char*,char*);
void endlist();
void opcode(label*,char**);
void org(label*,char**);
void base(label*,char**);
void pad(label*,char**);
void equ(label*,char**);
void equal(label*,char**);
void nothing(label*,char**);
void include(label*,char**);
void incbin(label*,char**);
void dw(label*,char**);
void db(label*,char**);
void dl(label*,char**);
void dh(label*,char**);
void hex(label*,char**);
void dsw(label*,char**);
void dsb(label*,char**);
void align(label*,char**);
void _if(label*,char**);
void ifdef(label*,char**);
void ifndef(label*,char**);
void elseif(label*,char**);
void _else(label*,char**);
void endif(label*,char**);
void macro(label*,char**);
void endm(label*,char**);
void endr(label*,char**);
void rept(label*,char**);
void _enum(label*,char**);
void ende(label*,char**);
void fillval(label*,char**);
void expandmacro(label*,char**,int,char*);
void expandrept(int,char*);
void make_error(label*,char**);
enum optypes {ACC,IMM,IND,INDX,INDY,ZPX,ZPY,ABSX,ABSY,ZP,ABS,REL,IMP};
int opsize[]={0,1,2,1,1,1,1,2,2,1,2,1,0};
char ophead[]={0,'#','(','(','(',0,0,0,0,0,0,0,0};
char *optail[]={"A","",")",",X)","),Y",",X",",Y",",X",",Y","","","",""};
byte brk[]={0x00,IMM,0x00,ZP,0x00,IMP,-1};
byte ora[]={0x09,IMM,0x01,INDX,0x11,INDY,0x15,ZPX,0x1d,ABSX,0x19,ABSY,0x05,ZP,0x0d,ABS,-1};
byte asl[]={0x0a,ACC,0x16,ZPX,0x1e,ABSX,0x06,ZP,0x0e,ABS,0x0a,IMP,-1};
byte php[]={0x08,IMP,-1};
byte bpl[]={0x10,REL,-1};
byte clc[]={0x18,IMP,-1};
byte jsr[]={0x20,ABS,-1};
byte and[]={0x29,IMM,0x21,INDX,0x31,INDY,0x35,ZPX,0x3d,ABSX,0x39,ABSY,0x25,ZP,0x2d,ABS,-1};
byte bit[]={0x24,ZP,0x2c,ABS,-1};
byte rol[]={0x2a,ACC,0x36,ZPX,0x3e,ABSX,0x26,ZP,0x2e,ABS,0x2a,IMP,-1};
byte plp[]={0x28,IMP,-1};
byte bmi[]={0x30,REL,-1};
byte sec[]={0x38,IMP,-1};
byte rti[]={0x40,IMP,-1};
byte eor[]={0x49,IMM,0x41,INDX,0x51,INDY,0x55,ZPX,0x5d,ABSX,0x59,ABSY,0x45,ZP,0x4d,ABS,-1};
byte lsr[]={0x4a,ACC,0x56,ZPX,0x5e,ABSX,0x46,ZP,0x4e,ABS,0x4a,IMP,-1};
byte pha[]={0x48,IMP,-1};
byte jmp[]={0x6c,IND,0x4c,ABS,-1};
byte bvc[]={0x50,REL,-1};
byte cli[]={0x58,IMP,-1};
byte rts[]={0x60,IMP,-1};
byte adc[]={0x69,IMM,0x61,INDX,0x71,INDY,0x75,ZPX,0x7d,ABSX,0x79,ABSY,0x65,ZP,0x6d,ABS,-1};
byte ror[]={0x6a,ACC,0x76,ZPX,0x7e,ABSX,0x66,ZP,0x6e,ABS,0x6a,IMP,-1};
byte pla[]={0x68,IMP,-1};
byte bvs[]={0x70,REL,-1};
byte sei[]={0x78,IMP,-1};
byte sta[]={0x81,INDX,0x91,INDY,0x95,ZPX,0x9d,ABSX,0x99,ABSY,0x85,ZP,0x8d,ABS,-1};
byte sty[]={0x94,ZPX,0x84,ZP,0x8c,ABS,-1};
byte stx[]={0x96,ZPY,0x86,ZP,0x8e,ABS,-1};
byte dey[]={0x88,IMP,-1};
byte txa[]={0x8a,IMP,-1};
byte bcc[]={0x90,REL,-1};
byte tya[]={0x98,IMP,-1};
byte txs[]={0x9a,IMP,-1};
byte ldy[]={0xa0,IMM,0xb4,ZPX,0xbc,ABSX,0xa4,ZP,0xac,ABS,-1};
byte lda[]={0xa9,IMM,0xa1,INDX,0xb1,INDY,0xb5,ZPX,0xbd,ABSX,0xb9,ABSY,0xa5,ZP,0xad,ABS,-1};
byte ldx[]={0xa2,IMM,0xb6,ZPY,0xbe,ABSY,0xa6,ZP,0xae,ABS,-1};
byte tay[]={0xa8,IMP,-1};
byte tax[]={0xaa,IMP,-1};
byte bcs[]={0xb0,REL,-1};
byte clv[]={0xb8,IMP,-1};
byte tsx[]={0xba,IMP,-1};
byte cpy[]={0xc0,IMM,0xc4,ZP,0xcc,ABS,-1};
byte cmp[]={0xc9,IMM,0xc1,INDX,0xd1,INDY,0xd5,ZPX,0xdd,ABSX,0xd9,ABSY,0xc5,ZP,0xcd,ABS,-1};
byte dec[]={0xd6,ZPX,0xde,ABSX,0xc6,ZP,0xce,ABS,-1};
byte iny[]={0xc8,IMP,-1};
byte dex[]={0xca,IMP,-1};
byte bne[]={0xd0,REL,-1};
byte cld[]={0xd8,IMP,-1};
byte cpx[]={0xe0,IMM,0xe4,ZP,0xec,ABS,-1};
byte sbc[]={0xe9,IMM,0xe1,INDX,0xf1,INDY,0xf5,ZPX,0xfd,ABSX,0xf9,ABSY,0xe5,ZP,0xed,ABS,-1};
byte inc[]={0xf6,ZPX,0xfe,ABSX,0xe6,ZP,0xee,ABS,-1};
byte inx[]={0xe8,IMP,-1};
byte nop[]={0xea,IMP,-1};
byte beq[]={0xf0,REL,-1};
byte sed[]={0xf8,IMP,-1};
void *rsvdlist[]={ //all reserved words
"BRK",brk,
"PHP",php,
"BPL",bpl,
"CLC",clc,
"JSR",jsr,
"PLP",plp,
"BMI",bmi,
"SEC",sec,
"RTI",rti,
"PHA",pha,
"BVC",bvc,
"CLI",cli,
"RTS",rts,
"PLA",pla,
"BVS",bvs,
"SEI",sei,
"DEY",dey,
"BCC",bcc,
"TYA",tya,
"LDY",ldy,
"TAY",tay,
"BCS",bcs,
"CLV",clv,
"CPY",cpy,
"INY",iny,
"BNE",bne,
"CLD",cld,
"CPX",cpx,
"INX",inx,
"BEQ",beq,
"SED",sed,
"ORA",ora,
"AND",and,
"EOR",eor,
"ADC",adc,
"STA",sta,
"LDA",lda,
"CMP",cmp,
"SBC",sbc,
"ASL",asl,
"ROL",rol,
"LSR",lsr,
"ROR",ror,
"TXA",txa,
"TXS",txs,
"LDX",ldx,
"TAX",tax,
"TSX",tsx,
"DEX",dex,
"NOP",nop,
"BIT",bit,
"JMP",jmp,
"STY",sty,
"STX",stx,
"DEC",dec,
"INC",inc,
0, 0
};
struct {
char* name;
void (*func)( label*, char** );
} directives[]={
"",nothing,
"IF",_if,
"ELSEIF",elseif,
"ELSE",_else,
"ENDIF",endif,
"IFDEF",ifdef,
"IFNDEF",ifndef,
"=",equal,
"EQU",equ,
"ORG",org,
"BASE",base,
"PAD",pad,
"INCLUDE",include,"INCSRC",include,
"INCBIN",incbin,"BIN",incbin,
"HEX",hex,
"WORD",dw,"DW",dw,"DCW",dw,"DC.W",dw,
"BYTE",db,"DB",db,"DCB",db,"DC.B",db,
"DSW",dsw,"DS.W",dsw,
"DSB",dsb,"DS.B",dsb,
"ALIGN",align,
"MACRO",macro,
"REPT",rept,
"ENDM",endm,
"ENDR",endr,
"ENUM",_enum,
"ENDE",ende,
"FILLVALUE",fillval,
"DL",dl,
"DH",dh,
"ERROR",make_error,
0, 0
};
char OutOfRange[]="Value out of range.";
char SeekOutOfRange[]="Seek position out of range.";
char BadIncbinSize[]="INCBIN size is out of range.";
char NotANumber[]="Not a number.";
char UnknownLabel[]="Unknown label.";
char Illegal[]="Illegal instruction.";
char IncompleteExp[]="Incomplete expression.";
char LabelDefined[]="Label already defined.";
char MissingOperand[]="Missing operand.";
char DivZero[]="Divide by zero.";
char BadAddr[]="Can't determine address.";
char NeedName[]="Need a name.";
char CantOpen[]="Can't open file.";
char ExtraENDM[]="ENDM without MACRO.";
char ExtraENDR[]="ENDR without REPT.";
char ExtraENDE[]="ENDE without ENUM.";
char RecurseMACRO[]="Recursive MACRO not allowed.";
char RecurseEQU[]="Recursive EQU not allowed.";
char NoENDIF[]="Missing ENDIF.";
char NoENDM[]="Missing ENDM.";
char NoENDR[]="Missing ENDR.";
char NoENDE[]="Missing ENDE.";
char IfNestLimit[]="Too many nested IFs.";
char undefinedPC[]="PC is undefined (use ORG first)";
char whitesp[]=" \t\r\n:"; //treat ":" like whitespace (for labels)
char whitesp2[]=" \t\r\n\""; //(used for filename processing)
char tmpstr[LINEMAX]; //all purpose big string
int pass=0;
int scope;//current scope, 0=global
int nextscope;//next nonglobal scope (increment on each new block of localized code)
int lastchance=0;//set on final attempt
int needanotherpass;//still need to take care of some things..
int error=0;//hard error (stop assembly after this pass)
char **makemacro=0;//(during macro creation) where next macro line will go. 1 to skip past macro
char **makerept;//like makemacro.. points to end of string chain
int reptcount=0;//counts rept statements during rept string storage
int iflevel=0;//index into ifdone[],skipline[]
int ifdone[IFNESTS];//nonzero if current IF level has been true
int skipline[IFNESTS];//1 on an IF statement that is false
const char *errmsg;
char *inputfilename=0;
char *outputfilename=0;
char *listfilename=0;
int verboselisting=0;//expand REPT loops in listing
const char *listerr=0;//error message for list file
label *labelhere;//points to the label being defined on the current line (for EQU, =, etc)
FILE *listfile=0;
FILE *outputfile=0;
byte outputbuff[BUFFSIZE];
byte inputbuff[BUFFSIZE];
int outcount;//bytes waiting in outputbuff
label **labellist; //array of label pointers (list starts from center and grows outward)
int labels;//# of labels in labellist
int maxlabels;//max # of labels labellist can hold
int labelstart;//index of first label
int labelend;//index of last label
label *lastlabel;//last label created
int nooutput=0;//supress output (use with ENUM)
int defaultfiller;//default fill value
int insidemacro=0;//macro/rept is being expanded
int verbose=1;
static void* ptr_from_bool( int b )
{
if ( b )
return true_ptr;
return NULL;
}
// Prints printf-style message to stderr, then exits.
// Closes and deletes output file.
static void fatal_error( const char fmt [], ... )
{
va_list args;
if ( outputfile != NULL ) {
fclose( outputfile );
remove( outputfilename );
}
va_start( args, fmt );
fprintf( stderr, "\nError: " );
vfprintf( stderr, fmt, args );
fprintf( stderr, "\n\n" );
va_end( args );
exit( EXIT_FAILURE );
}
// Prints printf-style message if verbose mode is enabled.
static void message( const char fmt [], ... )
{
if ( verbose ) {
va_list args;
va_start( args, fmt );
vprintf( fmt, args );
va_end( args );
}
}
// Same as malloc(), but prints error and exits if allocation fails
static char* my_malloc( size_t s )
{
char* p = malloc( s ? s : 1 );
if ( p == NULL )
fatal_error( "out of memory" );
return p;
}
// Same as common strdup(), but prints error and exits if allocation fails
static char* my_strdup(const char *in)
{
size_t size = strlen( in ) + 1;
char* out = my_malloc( size );
memcpy( out, in, size );
return out;
}
//-------------------------------------------------------
//parsing functions
//-------------------------------------------------------
// Not all systems support this, so we implement our own always.
// More problematic to try to use the system's version rather than
// ours in all cases.
char *my_strupr(char *string)
{
char *s;
if (string == NULL) {
return (char *)NULL;
}
for (s = string; *s; ++s) {
*s = toupper((unsigned char) *s);
}
return string;
}
int hexify(int i) {
if(i>='0' && i<='9') {
return i-'0';
} else if(i>='a' && i<='f') {
return i-('a'-10);
} else if(i>='A' && i<='F') {
return i-('A'-10);
} else {
errmsg=NotANumber;
return 0;
}
}
#define eatwhitespace(str) (*str+=strspn(*str,whitesp))
//find end of str, excluding any chars in whitespace
char *strend(char *str, char *whitespace) {
char c;
char *w=whitespace;
char *end=str+strlen(str);
while(*w && end!=str) {
for(w=whitespace, c=end[-1]; *w; w++) {
if(*w==c) {
end--;
break;
}
}
}
return end;
}
//decode str into a number
//set errmsg on error
char gvline[WORDMAX];
int dependant;//set to nonzero if symbol couldn't be resolved
int getvalue(char **str) {
char *s,*end;
int ret,chars,j;
label *p;
getword(gvline,str,1);
s=gvline;
if(!*s) {
errmsg=MissingOperand;
return 0;
}
ret=chars=0;
if(*s=='$') { //hex---------------------
s++;
if(!*s) {
ret=addr;//$ by itself is the PC
} else do {
hexi: j=hexify(*s);
s++;
chars++;
ret=(ret<<4)|j;
} while(*s);
if(chars>8)
errmsg=OutOfRange;
} else if(*s=='%') { //binary----------------------
s++;
do {
bin: j=*s;
s++;
chars++;
j-='0';
if(j>1) {
errmsg=NotANumber;
}
ret=(ret<<1)|j;
} while(*s);
if(chars>32)
errmsg=OutOfRange;
} else if(*s=='\'') { //char-----------------
s++;
if(*s=='\\') s++;
ret=*s;
s++;
if(*s!='\'')
errmsg=NotANumber;
} else if(*s=='"') { //char 2-----------------
s++;
if(*s=='\\') s++;
ret=*s;
s++;
if(*s!='"')
errmsg=NotANumber;
} else if(*s>='0' && *s<='9') {//number--------------
end=s+strlen(s)-1;
if(strspn(s,"0123456789")==strlen(s))
ret=atoi(s);
else if(*end=='b' || *end=='B') {
*end=0;
goto bin;
} else if(*end=='h' || *end=='H') {
*end=0;
goto hexi;
} else
errmsg=NotANumber;
} else { //label---------------
p=findlabel(gvline);
if(!p) {//label doesn't exist (yet?)
needanotherpass=dependant=1;
if(lastchance) {//only show error once we're certain label will never exist
errmsg=UnknownLabel;
}
} else {
dependant|=!(*p).line;
needanotherpass|=!(*p).line;
if((*p).type==LABEL || (*p).type==VALUE) {
ret=(*p).value;
} else if((*p).type==MACRO) {
errmsg="Can't use macro in expression.";
} else {//what else is there?
errmsg=UnknownLabel;
}
}
}
return ret;
}
char mathy[]="!^&|+-*/%()<>=,";
enum prectypes {WHOLEEXP,ORORP,ANDANDP,ORP,XORP,ANDP,EQCOMPARE,COMPARE,SHIFT,PLUSMINUS,MULDIV,UNARY};//precedence levels
enum operators {NOOP,EQUAL,NOTEQUAL,GREATER,GREATEREQ,LESS,LESSEQ,PLUS,MINUS,MUL,DIV,MOD,AND,XOR,OR,ANDAND,OROR,LEFTSHIFT,RIGHTSHIFT};//all operators
char prec[]={WHOLEEXP,EQCOMPARE,EQCOMPARE,COMPARE,COMPARE,COMPARE,COMPARE,PLUSMINUS,PLUSMINUS,MULDIV,MULDIV,MULDIV,ANDP,XORP,ORP,ANDANDP,ORORP,SHIFT,SHIFT};//precedence of each operator
//get operator from str and advance str
int getoperator(char **str) {
*str+=strspn(*str,whitesp); //eatwhitespace
(*str)++;
switch(*(*str-1)) {
case '&':
if(**str=='&') {
(*str)++;
return ANDAND;
} else
return AND;
case '|':
if(**str=='|') {
(*str)++;
return OROR;
} else
return OR;
case '^':
return XOR;
case '+':
return PLUS;
case '-':
return MINUS;
case '*':
return MUL;
case '%':
return MOD;
case '/':
return DIV;
case '=':
if(**str=='=')
(*str)++;
return EQUAL;
case '>':
if(**str=='=') {
(*str)++;
return GREATEREQ;
} else if(**str=='>') {
(*str)++;
return RIGHTSHIFT;
} else
return GREATER;
case '<':
if(**str=='=') {
(*str)++;
return LESSEQ;
} else if(**str=='>') {
(*str)++;
return NOTEQUAL;
} else if(**str=='<') {
(*str)++;
return LEFTSHIFT;
} else
return LESS;
case '!':
if(**str=='=') {
(*str)++;
return NOTEQUAL;
}
//(to default)
default:
(*str)--;
return NOOP;
}
}
//evaluate expression in str and advance str
int eval(char **str,int precedence) {
char unary;
char *s,*s2;
int ret,val2;
int op;
s=*str+strspn(*str,whitesp); //eatwhitespace
unary=*s;
switch(unary) {
case '(':
s++;
ret=eval(&s,WHOLEEXP);
s+=strspn(s,whitesp); //eatwhitespace
if(*s==')')
s++;
else
errmsg=IncompleteExp;
break;
case '#':
s++;
ret=eval(&s,WHOLEEXP);
break;
case '~':
s++;
ret=~eval(&s,UNARY);
break;
case '!':
s++;
ret=!eval(&s,UNARY);
break;
case '<':
s++;
ret=eval(&s,UNARY)&0xff;
break;
case '>':
s++;
ret=(eval(&s,UNARY)>>8)&0xff;
break;
case '+':
case '-':
//careful.. might be +-label
s2=s;
s++;
op=dependant;//eval() is reentrant so don't mess up dependant
val2=needanotherpass;
dependant=0;
ret=getvalue(&s2);
if (errmsg == UnknownLabel)
errmsg=0;
if(!dependant || s2==s) {//found something or single + -
s=s2;
s2=0;//flag that we got something
dependant|=op;
} else {//not a label after all..
dependant=op;
needanotherpass=val2;
}
if(s2) {//if it wasn't a +-label
ret=eval(&s,UNARY);
if(unary=='-') ret=-ret;
}
break;
default:
ret=getvalue(&s);
}
do {
*str=s;
op=getoperator(&s);
if(precedence<prec[op]) {
val2=eval(&s,prec[op]);
if(!dependant) switch(op) {
case AND:
ret&=val2;
break;
case ANDAND:
ret=ret&&val2;
break;
case OR:
ret|=val2;
break;
case OROR:
ret=ret||val2;
break;
case XOR:
ret^=val2;
break;
case PLUS:
ret+=val2;
break;
case MINUS:
ret-=val2;
break;
case MUL:
ret*=val2;
break;
case DIV:
if(!val2) errmsg=DivZero;
else ret/=val2;
break;
case MOD:
if(!val2) errmsg=DivZero;
else ret%=val2;
break;
case EQUAL:
ret=(ret==val2);
break;
case NOTEQUAL:
ret=(ret!=val2);
break;
case GREATER:
ret=ret>val2;
break;
case GREATEREQ:
ret=ret>=val2;
break;
case LESS:
ret=ret<val2;
break;
case LESSEQ:
ret=ret<=val2;
break;
case LEFTSHIFT:
ret<<=val2;
break;
case RIGHTSHIFT:
ret>>=val2;
break;
} else ret=0;
}
} while(precedence<prec[op] && !errmsg);
return ret;
}
//copy next word from src into dst and advance src
//mcheck=1 to crop mathy stuff (0 for filenames,etc)
void getword(char *dst,char **src,int mcheck) {
*src+=strspn(*src,whitesp);//eatwhitespace
strncpy(dst,*src,WORDMAX-1);
dst[WORDMAX-1]=0;
strtok(dst,whitesp);//no trailing whitespace
if(mcheck) strtok(dst,mathy);
*src+=strlen(dst);
if(**src==':') (*src)++;//cheesy fix for rept/macro listing
}
//grab string with optional quotes
void getfilename(char *dst, char **next) {
char *s,*end;
int len;
eatwhitespace(next);
if(**next=='"') { //look for end quote, grab everything inside
s=*next+1;
end=strchr(s,'"');
if(end) {
len=(int)(end-s);
memcpy(dst,s,len); dst[len]=0;
*next=end+1;
} else { //no end quote.. grab everything minus trailing whitespace
end=strend(s,whitesp);
len=(int)(end-s);
memcpy(dst,s,len); dst[len]=0;
*next=end;
}
} else {
getword(dst,next,0);
}
}
//get word in src, advance src, and return reserved label*
label *getreserved(char **src) {
char dst[WORDMAX];
char upp[WORDMAX];
label *p;
*src+=strspn(*src,whitesp);//eatwhitespace
if(**src=='=') {//special '=' reserved word
upp[0]='=';
upp[1]=0;
(*src)++;
} else {
if(**src=='.')//reserved words can start with "."
(*src)++;
getword(dst,src,1);
strcpy(upp,dst);
my_strupr(upp);
}
p=findlabel(upp);//case insensitive reserved word
if(!p) p=findlabel(dst);//or case sensitive macro
if(p) {
if((*p).type==MACRO) {
if((*p).pass!=pass)
p=0;
} else if((*p).type!=RESERVED)
p=0;
}
if(!p) errmsg=Illegal;
return p;
}
//copy word to dst, advance src
//return true if it looks like a label
int getlabel(char *dst,char **src) {
char *s;
char c;
getword(dst,src,1);
if(*dst=='$'&&!dst[1])//'$' label
return 1;
s=dst;//+label, -label
c=*s;
if(c=='+' || c=='-') {
do s++; while(*s==c);
if(!*s)//just ++.. or --.., no text
return 1;
}
c=*s;
if(c==LOCALCHAR || c=='_' || (c>='A' && c<='Z') || (c>='a' && c<='z')) {//label can start with these
return 1;
} else {
errmsg=Illegal;//fucked up instruction
return 0;
}
}
//Expand all equates from src into dst, and remove comment
//returns a pointer to the comment in src or null.
//CRIPES what a mess...
char *expandline(char *dst,char *src) {
char *start;
char *comment=0;
char c,c2;
label *p;
int def_skip=0;
char upp[WORDMAX];
do {
c=*src;
if(c=='$' || (c>='0' && c<='9')) {//read past numbers (could be mistaken for a symbol, i.e. $BEEF)
do {
*dst=c;
src++;
dst++;
c=*src;
} while((c>='0' && c<='9') || (c>='A' && c<='H') || (c>='a' && c<='h'));
c=1;//don't terminate yet
} else if(c=='"' || c=='\'') {//read past quotes
*dst=c;
dst++; src++;
do {
*dst=c2=*src;
if(c2=='\\') {
dst++; src++;
*dst=*src;
}
dst++; src++;
} while(c2 && c2!=c);
c=c2;
} else if(c=='_' || c=='.' || c==LOCALCHAR || (c>='A' && c<='Z') || (c>='a' && c<='z')) {//symbol
start=src;
do {//scan to end of symbol
src++;
c=*src;
} while(c=='_' || c=='.' || c==LOCALCHAR || (c>='0' && c<='9') || (c>='A' && c<='Z') || (c>='a' && c<='z'));
*src=0; //terminate @ end of word (temporarily)
/*
ghey hack.
expandline() is called quite early during parsing, so
FOO equ xxxx
ifdef FOO
becomes
FOO equ xxxx
ifdef xxxx
rendering IFDEF useless, so we will bypass expansion in this special case.
I'm avoiding getreserved() because it does searching and other unnecessary crap.
*/
p=0;
if(!def_skip) {
strcpy(upp,start+(*start=='.'));
my_strupr(upp);
if(!strcmp(upp,"IFDEF") || !strcmp(upp,"IFNDEF")) {
def_skip=1;
} else {
p=findlabel(start);
}
}
if(p) {
if((*p).type!=EQUATE || (*p).pass!=pass)//equates MUST be defined before being used otherwise they will be expanded in their own definition
p=0;//i.e. (label equ whatever) gets translated to (whatever equ whatever)
else {
if((*p).used) {
p=0;
errmsg=RecurseEQU;
}
}
}
if(p) {
(*p).used=1;
expandline(dst,(*p).line);
(*p).used=0;
} else {
strcpy(dst,start);
}
dst+=strlen(dst);
*src=c;
} else {
if(c==';') {//comment
c=0;
comment=src;
}
*dst=c;
dst++;
src++;
}
} while(c);
return comment;
}
int eatchar(char **str,char c) {
if(c) {
*str+=strspn(*str,whitesp); //eatwhitespace
if(**str==c) {
(*str)++;
return 1;
} else
return 0;
}
return 1;
}
//reverse string
void reverse(char *dst,char *src) {
dst+=strlen(src);
*dst=0;
while(*src)
*(--dst)=*(src++);
}
//===========================================================================================================
//local:
// false: if label starts with LOCALCHAR, make it local, otherwise it's global
// true: force label to be local (used for macros)
void addlabel(char *word, int local) {
char c=*word;
label *p=findlabel(word);
if(p && local && !(*p).scope && (*p).type!=VALUE) //if it's global and we're local
p=0;//pretend we didn't see it (local label overrides global of the same name)
//global labels advance scope
if(c!=LOCALCHAR && !local) {
scope=nextscope++;
}
if(!p) {//new label
labelhere=newlabel();
if(!(*labelhere).name)//name already set if it's a duplicate
(*labelhere).name=my_strdup(word);
(*labelhere).type=LABEL;//assume it's a label.. could mutate into something else later
(*labelhere).pass=pass;
(*labelhere).value=addr;
(*labelhere).line=ptr_from_bool(addr>=0);
(*labelhere).used=0;
if(c==LOCALCHAR || local) { //local
(*labelhere).scope=scope;
} else { //global