streval.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1982-2012 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* D. G. Korn
* AT&T Labs
*
* arithmetic expression evaluator
*
* this version compiles the expression onto a stack
* and has a separate executor
*/
#include "streval.h"
#include <ctype.h>
#include <error.h>
#include <stak.h>
#include "FEATURE/externs"
#include "defs.h" /* for sh.decomma */
#ifndef ERROR_dictionary
# define ERROR_dictionary(s) (s)
#endif
#ifndef SH_DICT
# define SH_DICT "libshell"
#endif
#define MAXLEVEL 9
#define SMALL_STACK 12
/*
* The following are used with tokenbits() macro
*/
#define T_OP 0x3f /* mask for operator number */
#define T_BINARY 0x40 /* binary operators */
#define T_NOFLOAT 0x80 /* non floating point operator */
#define A_LVALUE (2*MAXPREC+2)
#define pow2size(x) ((x)<=2?2:(x)<=4?4:(x)<=8?8:(x)<=16?16:(x)<=32?32:64)
#define round(x,size) (((x)+(size)-1)&~((size)-1))
#define stakpush(v,val,type) ((((v)->offset=round(staktell(),pow2size(sizeof(type)))),\
stakseek((v)->offset+sizeof(type)), \
*((type*)stakptr((v)->offset)) = (val)),(v)->offset)
#define roundptr(ep,cp,type) (((unsigned char*)(ep))+round(cp-((unsigned char*)(ep)),pow2size(sizeof(type))))
static int level;
struct vars /* vars stacked per invocation */
{
Shell_t *shp;
const char *expr; /* current expression */
const char *nextchr; /* next char in current expression */
const char *errchr; /* next char after error */
const char *errstr; /* error string */
struct lval errmsg; /* error message text */
int offset; /* offset for pushchr macro */
int staksize; /* current stack size needed */
int stakmaxsize; /* maximum stack size needed */
unsigned char paren; /* parenthesis level */
char infun; /* incremented by comma inside function */
int emode;
Sfdouble_t (*convert)(const char**,struct lval*,int,Sfdouble_t);
};
typedef Sfdouble_t (*Math_f)(Sfdouble_t,...);
typedef Sfdouble_t (*Math_1f_f)(Sfdouble_t);
typedef int (*Math_1i_f)(Sfdouble_t);
typedef Sfdouble_t (*Math_2f_f)(Sfdouble_t,Sfdouble_t);
typedef Sfdouble_t (*Math_2f_i)(Sfdouble_t,int);
typedef int (*Math_2i_f)(Sfdouble_t,Sfdouble_t);
typedef Sfdouble_t (*Math_3f_f)(Sfdouble_t,Sfdouble_t,Sfdouble_t);
typedef int (*Math_3i_f)(Sfdouble_t,Sfdouble_t,Sfdouble_t);
#define getchr(vp) (*(vp)->nextchr++)
#define peekchr(vp) (*(vp)->nextchr)
#define ungetchr(vp) ((vp)->nextchr--)
#if ('a'==97) /* ASCII encodings */
# define getop(c) (((c) >= sizeof(strval_states))? \
((c)=='|'?A_OR:((c)=='^'?A_XOR:((c)=='~'?A_TILDE:A_REG))):\
strval_states[(c)])
#else
# define getop(c) (isdigit(c)?A_DIG:((c==' '||c=='\t'||c=='\n'||c=='"')?0: \
(c=='<'?A_LT:(c=='>'?A_GT:(c=='='?A_ASSIGN: \
(c=='+'?A_PLUS:(c=='-'?A_MINUS:(c=='*'?A_TIMES: \
(c=='/'?A_DIV:(c=='%'?A_MOD:(c==','?A_COMMA: \
(c=='&'?A_AND:(c=='!'?A_NOT:(c=='('?A_LPAR: \
(c==')'?A_RPAR:(c==0?A_EOF:(c==':'?A_COLON: \
(c=='?'?A_QUEST:(c=='|'?A_OR:(c=='^'?A_XOR: \
(c=='\''?A_LIT: \
(c=='.'?A_DOT:(c=='~'?A_TILDE:A_REG)))))))))))))))))))))))
#endif
#define seterror(v,msg) _seterror(v,ERROR_dictionary(msg))
#define ERROR(vp,msg) return(seterror((vp),msg))
/*
* set error message string and return(0)
*/
static int _seterror(struct vars *vp,const char *msg)
{
if(!vp->errmsg.value)
vp->errmsg.value = (char*)msg;
vp->errchr = vp->nextchr;
vp->nextchr = "";
level = 0;
return(0);
}
static void arith_error(const char *message,const char *expr, int mode)
{
level = 0;
mode = (mode&3)!=0;
errormsg(SH_DICT,ERROR_exit(mode),message,expr);
}
#if _ast_no_um2fm
static Sfdouble_t U2F(Sfulong_t u)
{
Sflong_t s = u;
Sfdouble_t f;
if (s >= 0)
return s;
s = u / 2;
f = s;
f *= 2;
if (u & 1)
f++;
return f;
}
#else
#define U2F(x) x
#endif
Sfdouble_t arith_exec(Arith_t *ep)
{
register Sfdouble_t num=0,*dp,*sp;
register unsigned char *cp = ep->code;
register int c,type=0;
register char *tp;
Sfdouble_t small_stack[SMALL_STACK+1],arg[9];
const char *ptr = "";
char *lastval=0;
int lastsub;
Math_f fun;
struct lval node;
Shell_t *shp = ep->shp;
node.shp = shp;
node.emode = ep->emode;
node.expr = ep->expr;
node.elen = ep->elen;
node.value = 0;
node.nosub = 0;
node.ptr = 0;
node.eflag = 0;
if(level++ >=MAXLEVEL)
{
arith_error(e_recursive,ep->expr,ep->emode);
return(0);
}
if(ep->staksize < SMALL_STACK)
sp = small_stack;
else
sp = (Sfdouble_t*)stakalloc(ep->staksize*(sizeof(Sfdouble_t)+1));
tp = (char*)(sp+ep->staksize);
tp--,sp--;
while(c = *cp++)
{
if(c&T_NOFLOAT)
{
if(type==1 || ((c&T_BINARY) && (c&T_OP)!=A_MOD && tp[-1]==1))
arith_error(e_incompatible,ep->expr,ep->emode);
}
switch(c&T_OP)
{
case A_JMP: case A_JMPZ: case A_JMPNZ:
c &= T_OP;
cp = roundptr(ep,cp,short);
if((c==A_JMPZ && num) || (c==A_JMPNZ &&!num))
cp += sizeof(short);
else
cp = (unsigned char*)ep + *((short*)cp);
continue;
case A_NOTNOT:
num = (num!=0);
type=0;
break;
case A_PLUSPLUS:
node.nosub = -1;
(*ep->fun)(&ptr,&node,ASSIGN,num+1);
break;
case A_MINUSMINUS:
node.nosub = -1;
(*ep->fun)(&ptr,&node,ASSIGN,num-1);
break;
case A_INCR:
num = num+1;
node.nosub = -1;
num = (*ep->fun)(&ptr,&node,ASSIGN,num);
break;
case A_DECR:
num = num-1;
node.nosub = -1;
num = (*ep->fun)(&ptr,&node,ASSIGN,num);
break;
case A_SWAP:
num = sp[-1];
sp[-1] = *sp;
type = tp[-1];
tp[-1] = *tp;
break;
case A_POP:
sp--;
continue;
case A_ASSIGNOP1:
node.emode |= ARITH_ASSIGNOP;
case A_PUSHV:
cp = roundptr(ep,cp,Sfdouble_t*);
dp = *((Sfdouble_t**)cp);
cp += sizeof(Sfdouble_t*);
c = *(short*)cp;
cp += sizeof(short);
lastval = node.value = (char*)dp;
if(node.flag = c)
lastval = 0;
node.isfloat=0;
node.level = level;
node.nosub = 0;
num = (*ep->fun)(&ptr,&node,VALUE,num);
if(node.emode&ARITH_ASSIGNOP)
{
lastsub = node.nosub;
node.nosub = 0;
node.emode &= ~ARITH_ASSIGNOP;
}
if(node.value != (char*)dp)
arith_error(node.value,ptr,ep->emode);
*++sp = num;
type = node.isfloat;
if(num > LDBL_ULLONG_MAX || num < LDBL_LLONG_MIN)
type = 1;
else
{
Sfdouble_t d=num;
if(num > LDBL_LLONG_MAX && num <= LDBL_ULLONG_MAX)
{
type = 2;
d -= LDBL_LLONG_MAX;
}
if((Sflong_t)d!=d)
type = 1;
}
*++tp = type;
c = 0;
break;
case A_ENUM:
node.eflag = 1;
continue;
case A_ASSIGNOP:
node.nosub = lastsub;
case A_STORE:
cp = roundptr(ep,cp,Sfdouble_t*);
dp = *((Sfdouble_t**)cp);
cp += sizeof(Sfdouble_t*);
c = *(short*)cp;
if(c<0)
c = 0;
cp += sizeof(short);
node.value = (char*)dp;
node.flag = c;
if(lastval)
node.eflag = 1;
node.ptr = 0;
num = (*ep->fun)(&ptr,&node,ASSIGN,num);
if(lastval && node.ptr)
{
Sfdouble_t r;
node.flag = 0;
node.value = lastval;
r = (*ep->fun)(&ptr,&node,VALUE,num);
if(r!=num)
{
node.flag=c;
node.value = (char*)dp;
num = (*ep->fun)(&ptr,&node,ASSIGN,r);
}
}
lastval = 0;
c=0;
break;
case A_PUSHF:
cp = roundptr(ep,cp,Math_f);
*++sp = (Sfdouble_t)(cp-ep->code);
cp += sizeof(Math_f);
*++tp = *cp++;
continue;
case A_PUSHN:
cp = roundptr(ep,cp,Sfdouble_t);
num = *((Sfdouble_t*)cp);
cp += sizeof(Sfdouble_t);
*++sp = num;
*++tp = type = *cp++;
break;
case A_NOT:
type=0;
num = !num;
break;
case A_UMINUS:
num = -num;
break;
case A_TILDE:
num = ~((Sflong_t)(num));
break;
case A_PLUS:
num += sp[-1];
break;
case A_MINUS:
num = sp[-1] - num;
break;
case A_TIMES:
num *= sp[-1];
break;
case A_POW:
num = pow(sp[-1],num);
break;
case A_MOD:
if(!(Sflong_t)num)
arith_error(e_divzero,ep->expr,ep->emode);
if(type==2 || tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) % (Sfulong_t)(num));
else
num = (Sflong_t)(sp[-1]) % (Sflong_t)(num);
break;
case A_DIV:
if(type==1 || tp[-1]==1)
{
num = sp[-1]/num;
type = 1;
}
else if((Sfulong_t)(num)==0)
arith_error(e_divzero,ep->expr,ep->emode);
else if(type==2 || tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) / (Sfulong_t)(num));
else
num = (Sflong_t)(sp[-1]) / (Sflong_t)(num);
break;
case A_LSHIFT:
if(tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) << (long)(num));
else
num = (Sflong_t)(sp[-1]) << (long)(num);
break;
case A_RSHIFT:
if(tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) >> (long)(num));
else
num = (Sflong_t)(sp[-1]) >> (long)(num);
break;
case A_XOR:
if(type==2 || tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) ^ (Sfulong_t)(num));
else
num = (Sflong_t)(sp[-1]) ^ (Sflong_t)(num);
break;
case A_OR:
if(type==2 || tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) | (Sfulong_t)(num));
else
num = (Sflong_t)(sp[-1]) | (Sflong_t)(num);
break;
case A_AND:
if(type==2 || tp[-1]==2)
num = U2F((Sfulong_t)(sp[-1]) & (Sfulong_t)(num));
else
num = (Sflong_t)(sp[-1]) & (Sflong_t)(num);
break;
case A_EQ:
num = (sp[-1]==num);
type=0;
break;
case A_NEQ:
num = (sp[-1]!=num);
type=0;
break;
case A_LE:
num = (sp[-1]<=num);
type=0;
break;
case A_GE:
num = (sp[-1]>=num);
type=0;
break;
case A_GT:
num = (sp[-1]>num);
type=0;
break;
case A_LT:
num = (sp[-1]<num);
type=0;
break;
case A_CALL1F:
sp--,tp--;
fun = *((Math_f*)(ep->code+(int)(*sp)));
type = *tp;
if(c&T_BINARY)
{
c &= ~T_BINARY;
arg[0] = num;
arg[1] = 0;
num = sh_mathfun(shp,(void*)fun,1,arg);
break;
}
num = (*((Math_1f_f)fun))(num);
break;
case A_CALL1I:
sp--,tp--;
fun = *((Math_f*)(ep->code+(int)(*sp)));
type = *tp;
num = (*((Math_1i_f)fun))(num);
break;
case A_CALL2F:
sp-=2,tp-=2;
fun = *((Math_f*)(ep->code+(int)(*sp)));
type = *tp;
if(c&T_BINARY)
{
c &= ~T_BINARY;
arg[0] = sp[1];
arg[1] = num;
arg[2] = 0;
num = sh_mathfun(shp,(void*)fun,2,arg);
break;
}
if(c&T_NOFLOAT)
num = (*((Math_2f_i)fun))(sp[1],(int)num);
else
num = (*((Math_2f_f)fun))(sp[1],num);
break;
case A_CALL2I:
sp-=2,tp-=2;
fun = *((Math_f*)(ep->code+(int)(*sp)));
type = *tp;
num = (*((Math_2i_f)fun))(sp[1],num);
break;
case A_CALL3F:
sp-=3,tp-=3;
fun = *((Math_f*)(ep->code+(int)(*sp)));
type = *tp;
if(c&T_BINARY)
{
c &= ~T_BINARY;
arg[0] = sp[1];
arg[1] = sp[2];
arg[2] = num;
arg[3] = 0;
num = sh_mathfun(shp,(void*)fun,3,arg);
break;
}
num = (*((Math_3f_f)fun))(sp[1],sp[2],num);
break;
}
if(c)
lastval = 0;
if(c&T_BINARY)
{
node.ptr = 0;
sp--,tp--;
type |= (*tp!=0);
}
*sp = num;
*tp = type;
}
if(level>0)
level--;
if(type==0 && !num)
num = 0;
return(num);
}
/*
* This returns operator tokens or A_REG or A_NUM
*/
static int gettok(register struct vars *vp)
{
register int c,op;
vp->errchr = vp->nextchr;
while(1)
{
c = getchr(vp);
switch(op=getop(c))
{
case 0:
vp->errchr = vp->nextchr;
continue;
case A_EOF:
vp->nextchr--;
break;
case A_COMMA:
if(vp->shp->decomma && (c=peekchr(vp))>='0' && c<='9')
{
op = A_DIG;
goto keep;
}
break;
case A_DOT:
if((c=peekchr(vp))>='0' && c<='9')
op = A_DIG;
else
op = A_REG;
/*FALL THRU*/
case A_DIG: case A_REG: case A_LIT:
keep:
ungetchr(vp);
break;
case A_QUEST:
if(peekchr(vp)==':')
{
getchr(vp);
op = A_QCOLON;
}
break;
case A_LT: case A_GT:
if(peekchr(vp)==c)
{
getchr(vp);
op -= 2;
break;
}
/* FALL THRU */
case A_NOT: case A_COLON:
c = '=';
/* FALL THRU */
case A_ASSIGN:
case A_TIMES:
case A_PLUS: case A_MINUS:
case A_OR: case A_AND:
if(peekchr(vp)==c)
{
getchr(vp);
op--;
}
}
return(op);
}
}
/*
* evaluate a subexpression with precedence
*/
static int expr(register struct vars *vp,register int precedence)
{
register int c, op;
int invalid,wasop=0;
struct lval lvalue,assignop;
const char *pos;
Sfdouble_t d;
lvalue.value = 0;
lvalue.nargs = 0;
lvalue.fun = 0;
lvalue.shp = vp->shp;
again:
op = gettok(vp);
c = 2*MAXPREC+1;
switch(op)
{
case A_PLUS:
goto again;
case A_EOF:
if(precedence>2)
ERROR(vp,e_moretokens);
return(1);
case A_MINUS:
op = A_UMINUS;
goto common;
case A_NOT:
goto common;
case A_MINUSMINUS:
c = A_LVALUE;
op = A_DECR|T_NOFLOAT;
goto common;
case A_PLUSPLUS:
c = A_LVALUE;
op = A_INCR|T_NOFLOAT;
/* FALL THRU */
case A_TILDE:
op |= T_NOFLOAT;
common:
if(!expr(vp,c))
return(0);
stakputc(op);
break;
default:
vp->nextchr = vp->errchr;
wasop = 1;
}
invalid = wasop;
while(1)
{
assignop.value = 0;
op = gettok(vp);
if(op==A_DIG || op==A_REG || op==A_LIT)
{
if(!wasop)
ERROR(vp,e_synbad);
goto number;
}
if(wasop++ && op!=A_LPAR)
ERROR(vp,e_synbad);
/* check for assignment operation */
if(peekchr(vp)== '=' && !(strval_precedence[op]&NOASSIGN))
{
if((!lvalue.value || precedence > 3))
ERROR(vp,e_notlvalue);
if(precedence==3)
precedence = 2;
assignop = lvalue;
getchr(vp);
c = 3;
}
else
{
c = (strval_precedence[op]&PRECMASK);
if(c==MAXPREC || op==A_POW)
c++;
c *= 2;
}
/* from here on c is the new precedence level */
if(lvalue.value && (op!=A_ASSIGN))
{
if(vp->staksize++>=vp->stakmaxsize)
vp->stakmaxsize = vp->staksize;
if(op==A_EQ || op==A_NEQ)
stakputc(A_ENUM);
stakputc(assignop.value?A_ASSIGNOP1:A_PUSHV);
stakpush(vp,lvalue.value,char*);
if(lvalue.flag<0)
lvalue.flag = 0;
stakpush(vp,lvalue.flag,short);
if(vp->nextchr==0)
ERROR(vp,e_badnum);
if(!(strval_precedence[op]&SEQPOINT))
lvalue.value = 0;
invalid = 0;
}
else if(precedence==A_LVALUE)
ERROR(vp,e_notlvalue);
if(invalid && op>A_ASSIGN)
ERROR(vp,e_synbad);
if(precedence >= c)
goto done;
if(strval_precedence[op]&RASSOC)
c--;
if((c < (2*MAXPREC+1)) && !(strval_precedence[op]&SEQPOINT))
{
wasop = 0;
if(!expr(vp,c))
return(0);
}
switch(op)
{
case A_RPAR:
if(!vp->paren)
ERROR(vp,e_paren);
if(invalid)
ERROR(vp,e_synbad);
goto done;
case A_COMMA:
wasop = 0;
if(vp->infun)
vp->infun++;
else
{
stakputc(A_POP);
vp->staksize--;
}
if(!expr(vp,c))
{
stakseek(staktell()-1);
return(0);
}
lvalue.value = 0;
break;
case A_LPAR:
{
int infun = vp->infun;
int userfun=0;
Sfdouble_t (*fun)(Sfdouble_t,...);
int nargs = lvalue.nargs;
if(nargs<0)
nargs = -nargs;
fun = lvalue.fun;
lvalue.fun = 0;
if(fun)
{
if(vp->staksize++>=vp->stakmaxsize)
vp->stakmaxsize = vp->staksize;
vp->infun=1;
if((int)lvalue.nargs<0)
userfun = T_BINARY;
else if((int)lvalue.nargs&040)
userfun = T_NOFLOAT;
stakputc(A_PUSHF);
stakpush(vp,fun,Math_f);
stakputc(1);
}
else
vp->infun = 0;
if(!invalid)
ERROR(vp,e_synbad);
vp->paren++;
if(!expr(vp,1))
return(0);
vp->paren--;
if(fun)
{
int x= (nargs&010)?2:-1;
nargs &= 7;
if(vp->infun != nargs)
ERROR(vp,e_argcount);
if((vp->staksize+=nargs)>=vp->stakmaxsize)
vp->stakmaxsize = vp->staksize+nargs;
stakputc(A_CALL1F+userfun+nargs+x);
vp->staksize -= nargs;
}
vp->infun = infun;
if (gettok(vp) != A_RPAR)
ERROR(vp,e_paren);
wasop = 0;
break;
}
case A_PLUSPLUS:
case A_MINUSMINUS:
wasop=0;
op |= T_NOFLOAT;
case A_ASSIGN:
if(!lvalue.value)
ERROR(vp,e_notlvalue);
if(op==A_ASSIGN)
{
stakputc(A_STORE);
stakpush(vp,lvalue.value,char*);
stakpush(vp,lvalue.flag,short);
vp->staksize--;
}
else
stakputc(op);
lvalue.value = 0;
break;
case A_QUEST:
{
int offset1,offset2;
stakputc(A_JMPZ);
offset1 = stakpush(vp,0,short);
stakputc(A_POP);
if(!expr(vp,1))
return(0);
if(gettok(vp)!=A_COLON)
ERROR(vp,e_questcolon);
stakputc(A_JMP);
offset2 = stakpush(vp,0,short);
*((short*)stakptr(offset1)) = staktell();
stakputc(A_POP);
if(!expr(vp,3))
return(0);
*((short*)stakptr(offset2)) = staktell();
lvalue.value = 0;
wasop = 0;
break;
}
case A_COLON:
ERROR(vp,e_badcolon);
break;
case A_QCOLON:
case A_ANDAND:
case A_OROR:
{
int offset;
if(op==A_ANDAND)
op = A_JMPZ;
else
op = A_JMPNZ;
stakputc(op);
offset = stakpush(vp,0,short);
stakputc(A_POP);
if(!expr(vp,c))
return(0);
*((short*)stakptr(offset)) = staktell();
if(op!=A_QCOLON)
stakputc(A_NOTNOT);
lvalue.value = 0;
wasop=0;
break;
}
case A_AND: case A_OR: case A_XOR: case A_LSHIFT:
case A_RSHIFT: case A_MOD:
op |= T_NOFLOAT;
/* FALL THRU */
case A_PLUS: case A_MINUS: case A_TIMES: case A_DIV:
case A_EQ: case A_NEQ: case A_LT: case A_LE:
case A_GT: case A_GE: case A_POW:
stakputc(op|T_BINARY);
vp->staksize--;
break;
case A_NOT: case A_TILDE:
default:
ERROR(vp,e_synbad);
number:
wasop = 0;
if(*vp->nextchr=='L' && vp->nextchr[1]=='\'')
{
vp->nextchr++;
op = A_LIT;
}
pos = vp->nextchr;
lvalue.isfloat = 0;
lvalue.expr = vp->expr;
lvalue.emode = vp->emode;
if(op==A_LIT)
{
/* character constants */
if(pos[1]=='\\' && pos[2]=='\'' && pos[3]!='\'')
{
d = '\\';
vp->nextchr +=2;
}
else
d = chresc(pos+1,(char**)&vp->nextchr);
/* posix allows the trailing ' to be optional */
if(*vp->nextchr=='\'')
vp->nextchr++;
}
else
d = (*vp->convert)(&vp->nextchr, &lvalue, LOOKUP, 0);
if (vp->nextchr == pos)
{
if(vp->errmsg.value = lvalue.value)
vp->errstr = pos;
ERROR(vp,op==A_LIT?e_charconst:e_synbad);
}
if(op==A_DIG || op==A_LIT)
{
stakputc(A_PUSHN);
if(vp->staksize++>=vp->stakmaxsize)
vp->stakmaxsize = vp->staksize;
stakpush(vp,d,Sfdouble_t);
stakputc(lvalue.isfloat);
}
/* check for function call */
if(lvalue.fun)
continue;
break;
}
invalid = 0;
if(assignop.value)
{
if(vp->staksize++>=vp->stakmaxsize)
vp->stakmaxsize = vp->staksize;
if(assignop.flag<0)
assignop.flag = 0;
stakputc(c&1?A_ASSIGNOP:A_STORE);
stakpush(vp,assignop.value,char*);
stakpush(vp,assignop.flag,short);
}
}
done:
vp->nextchr = vp->errchr;
return(1);
}
Arith_t *arith_compile(Shell_t *shp,const char *string,char **last,Sfdouble_t(*fun)(const char**,struct lval*,int,Sfdouble_t),int emode)
{
struct vars cur;
register Arith_t *ep;
int offset;
memset((void*)&cur,0,sizeof(cur));
cur.shp = shp;
cur.expr = cur.nextchr = string;
cur.convert = fun;
cur.emode = emode;
cur.errmsg.value = 0;
cur.errmsg.emode = emode;
stakseek(sizeof(Arith_t));
if(!expr(&cur,0) && cur.errmsg.value)
{
if(cur.errstr)
string = cur.errstr;
if((*fun)( &string , &cur.errmsg, MESSAGE, 0) < 0)
{
stakseek(0);
*last = (char*)Empty;
return(0);
}
cur.nextchr = cur.errchr;
}
stakputc(0);
offset = staktell();
ep = (Arith_t*)stakfreeze(0);
ep->shp = shp;
ep->expr = string;
ep->elen = strlen(string);
ep->code = (unsigned char*)(ep+1);
ep->fun = fun;
ep->emode = emode;
ep->size = offset - sizeof(Arith_t);
ep->staksize = cur.stakmaxsize+1;
if(last)
*last = (char*)(cur.nextchr);
return(ep);
}
/*
* evaluate an integer arithmetic expression in s
*
* (Sfdouble_t)(*convert)(char** end, struct lval* string, int type, Sfdouble_t value)
* is a user supplied conversion routine that is called when unknown
* chars are encountered.
* *end points to the part to be converted and must be adjusted by convert to
* point to the next non-converted character; if typ is MESSAGE then string
* points to an error message string
*
* NOTE: (*convert)() may call strval()
*/
Sfdouble_t strval(Shell_t *shp,const char *s,char **end,Sfdouble_t(*conv)(const char**,struct lval*,int,Sfdouble_t),int emode)
{
Arith_t *ep;
Sfdouble_t d;
char *sp=0;
int offset;
if(offset=staktell())
sp = stakfreeze(1);
ep = arith_compile(shp,s,end,conv,emode);
ep->emode = emode;
d = arith_exec(ep);
stakset(sp?sp:(char*)ep,offset);
return(d);
}
#if _mem_name__exception
#undef _mem_name_exception
#define _mem_name_exception 1
#undef exception
#define exception _exception
#undef matherr
#endif
#if _mem_name_exception
#undef error
#if _BLD_shell && defined(__EXPORT__)
#define extern __EXPORT__
#endif
#ifndef DOMAIN
#define DOMAIN _DOMAIN
#endif
#ifndef OVERFLOW
#define OVERFLOW _OVERFLOW
#endif
#ifndef SING
#define SING _SING
#endif
extern int matherr(struct exception *ep)
{
const char *message;
switch(ep->type)
{
#ifdef DOMAIN
case DOMAIN:
message = ERROR_dictionary(e_domain);
break;
#endif
#ifdef OVERFLOW
case OVERFLOW:
message = ERROR_dictionary(e_overflow);
break;
#endif
#ifdef SING
case SING:
message = ERROR_dictionary(e_singularity);
break;
#endif
default:
return(1);
}
level=0;
errormsg(SH_DICT,ERROR_exit(1),message,ep->name);
return(0);
}
#undef extern
#endif /* _mem_name_exception */