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scheme.c
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/* T I N Y S C H E M E 1 . 3 9
* Dimitrios Souflis ([email protected])
* Based on MiniScheme (original credits follow)
* (MINISCM) coded by Atsushi Moriwaki (11/5/1989)
* (MINISCM) E-MAIL : [email protected]
* (MINISCM) This version has been modified by R.C. Secrist.
* (MINISCM)
* (MINISCM) Mini-Scheme is now maintained by Akira KIDA.
* (MINISCM)
* (MINISCM) This is a revised and modified version by Akira KIDA.
* (MINISCM) current version is 0.85k4 (15 May 1994)
*
*/
#define _SCHEME_SOURCE
#include "scheme-private.h"
#ifndef WIN32
# include <unistd.h>
#endif
#ifdef WIN32
#define snprintf _snprintf
#endif
#if USE_DL
# include "dynload.h"
#endif
#if USE_MATH
# include <math.h>
#endif
#include <limits.h>
#include <float.h>
#include <ctype.h>
#if USE_STRCASECMP
#include <strings.h>
# ifndef __APPLE__
# define stricmp strcasecmp
# endif
#endif
/* Used for documentation purposes, to signal functions in 'interface' */
#define INTERFACE
#define TOK_EOF (-1)
#define TOK_LPAREN 0
#define TOK_RPAREN 1
#define TOK_DOT 2
#define TOK_ATOM 3
#define TOK_QUOTE 4
#define TOK_COMMENT 5
#define TOK_DQUOTE 6
#define TOK_BQUOTE 7
#define TOK_COMMA 8
#define TOK_ATMARK 9
#define TOK_SHARP 10
#define TOK_SHARP_CONST 11
#define TOK_VEC 12
# define BACKQUOTE '`'
/*
* Basic memory allocation units
*/
#define banner "TinyScheme 1.39"
#include <string.h>
#include <stdlib.h>
#ifdef __APPLE__
static int stricmp(const char *s1, const char *s2)
{
unsigned char c1, c2;
do {
c1 = tolower(*s1);
c2 = tolower(*s2);
if (c1 < c2)
return -1;
else if (c1 > c2)
return 1;
s1++, s2++;
} while (c1 != 0);
return 0;
}
#endif /* __APPLE__ */
#if USE_STRLWR
static const char *strlwr(char *s) {
const char *p=s;
while(*s) {
*s=tolower(*s);
s++;
}
return p;
}
#endif
#ifndef prompt
# define prompt "ts> "
#endif
#ifndef InitFile
# define InitFile "init.scm"
#endif
#ifndef FIRST_CELLSEGS
# define FIRST_CELLSEGS 3
#endif
enum scheme_types {
T_STRING=1,
T_NUMBER=2,
T_SYMBOL=3,
T_PROC=4,
T_PAIR=5,
T_CLOSURE=6,
T_CONTINUATION=7,
T_FOREIGN=8,
T_CHARACTER=9,
T_PORT=10,
T_VECTOR=11,
T_MACRO=12,
T_PROMISE=13,
T_ENVIRONMENT=14,
T_LAST_SYSTEM_TYPE=14
};
/* ADJ is enough slack to align cells in a TYPE_BITS-bit boundary */
#define ADJ 32
#define TYPE_BITS 5
#define T_MASKTYPE 31 /* 0000000000011111 */
#define T_SYNTAX 4096 /* 0001000000000000 */
#define T_IMMUTABLE 8192 /* 0010000000000000 */
#define T_ATOM 16384 /* 0100000000000000 */ /* only for gc */
#define CLRATOM 49151 /* 1011111111111111 */ /* only for gc */
#define MARK 32768 /* 1000000000000000 */
#define UNMARK 32767 /* 0111111111111111 */
static num num_add(num a, num b);
static num num_mul(num a, num b);
static num num_div(num a, num b);
static num num_intdiv(num a, num b);
static num num_sub(num a, num b);
static num num_rem(num a, num b);
static num num_mod(num a, num b);
static int num_eq(num a, num b);
static int num_gt(num a, num b);
static int num_ge(num a, num b);
static int num_lt(num a, num b);
static int num_le(num a, num b);
#if USE_MATH
static double round_per_R5RS(double x);
#endif
static int is_zero_double(double x);
static INLINE int num_is_integer(pointer p) {
return ((p)->_object._number.is_fixnum);
}
static num num_zero;
static num num_one;
/* macros for cell operations */
#define typeflag(p) ((p)->_flag)
#define type(p) (typeflag(p)&T_MASKTYPE)
INTERFACE INLINE int is_string(pointer p) { return (type(p)==T_STRING); }
#define strvalue(p) ((p)->_object._string._svalue)
#define strlength(p) ((p)->_object._string._length)
INTERFACE static int is_list(scheme *sc, pointer p);
INTERFACE INLINE int is_vector(pointer p) { return (type(p)==T_VECTOR); }
INTERFACE static void fill_vector(pointer vec, pointer obj);
INTERFACE static pointer vector_elem(pointer vec, int ielem);
INTERFACE static pointer set_vector_elem(pointer vec, int ielem, pointer a);
INTERFACE INLINE int is_number(pointer p) { return (type(p)==T_NUMBER); }
INTERFACE INLINE int is_integer(pointer p) {
return is_number(p) && ((p)->_object._number.is_fixnum);
}
INTERFACE INLINE int is_real(pointer p) {
return is_number(p) && (!(p)->_object._number.is_fixnum);
}
INTERFACE INLINE int is_character(pointer p) { return (type(p)==T_CHARACTER); }
INTERFACE INLINE char *string_value(pointer p) { return strvalue(p); }
INLINE num nvalue(pointer p) { return ((p)->_object._number); }
INTERFACE long ivalue(pointer p) { return (num_is_integer(p)?(p)->_object._number.value.ivalue:(long)(p)->_object._number.value.rvalue); }
INTERFACE double rvalue(pointer p) { return (!num_is_integer(p)?(p)->_object._number.value.rvalue:(double)(p)->_object._number.value.ivalue); }
#define ivalue_unchecked(p) ((p)->_object._number.value.ivalue)
#define rvalue_unchecked(p) ((p)->_object._number.value.rvalue)
#define set_num_integer(p) (p)->_object._number.is_fixnum=1;
#define set_num_real(p) (p)->_object._number.is_fixnum=0;
INTERFACE long charvalue(pointer p) { return ivalue_unchecked(p); }
INTERFACE INLINE int is_port(pointer p) { return (type(p)==T_PORT); }
INTERFACE INLINE int is_inport(pointer p) { return is_port(p) && p->_object._port->kind & port_input; }
INTERFACE INLINE int is_outport(pointer p) { return is_port(p) && p->_object._port->kind & port_output; }
INTERFACE INLINE int is_pair(pointer p) { return (type(p)==T_PAIR); }
#define car(p) ((p)->_object._cons._car)
#define cdr(p) ((p)->_object._cons._cdr)
INTERFACE pointer pair_car(pointer p) { return car(p); }
INTERFACE pointer pair_cdr(pointer p) { return cdr(p); }
INTERFACE pointer set_car(pointer p, pointer q) { return car(p)=q; }
INTERFACE pointer set_cdr(pointer p, pointer q) { return cdr(p)=q; }
INTERFACE INLINE int is_symbol(pointer p) { return (type(p)==T_SYMBOL); }
INTERFACE INLINE char *symname(pointer p) { return strvalue(car(p)); }
#if USE_PLIST
SCHEME_EXPORT INLINE int hasprop(pointer p) { return (typeflag(p)&T_SYMBOL); }
#define symprop(p) cdr(p)
#endif
INTERFACE INLINE int is_syntax(pointer p) { return (typeflag(p)&T_SYNTAX); }
INTERFACE INLINE int is_proc(pointer p) { return (type(p)==T_PROC); }
INTERFACE INLINE int is_foreign(pointer p) { return (type(p)==T_FOREIGN); }
INTERFACE INLINE char *syntaxname(pointer p) { return strvalue(car(p)); }
#define procnum(p) ivalue(p)
static const char *procname(pointer x);
INTERFACE INLINE int is_closure(pointer p) { return (type(p)==T_CLOSURE); }
INTERFACE INLINE int is_macro(pointer p) { return (type(p)==T_MACRO); }
INTERFACE INLINE pointer closure_code(pointer p) { return car(p); }
INTERFACE INLINE pointer closure_env(pointer p) { return cdr(p); }
INTERFACE INLINE int is_continuation(pointer p) { return (type(p)==T_CONTINUATION); }
#define cont_dump(p) cdr(p)
/* To do: promise should be forced ONCE only */
INTERFACE INLINE int is_promise(pointer p) { return (type(p)==T_PROMISE); }
INTERFACE INLINE int is_environment(pointer p) { return (type(p)==T_ENVIRONMENT); }
#define setenvironment(p) typeflag(p) = T_ENVIRONMENT
#define is_atom(p) (typeflag(p)&T_ATOM)
#define setatom(p) typeflag(p) |= T_ATOM
#define clratom(p) typeflag(p) &= CLRATOM
#define is_mark(p) (typeflag(p)&MARK)
#define setmark(p) typeflag(p) |= MARK
#define clrmark(p) typeflag(p) &= UNMARK
INTERFACE INLINE int is_immutable(pointer p) { return (typeflag(p)&T_IMMUTABLE); }
/*#define setimmutable(p) typeflag(p) |= T_IMMUTABLE*/
INTERFACE INLINE void setimmutable(pointer p) { typeflag(p) |= T_IMMUTABLE; }
#define caar(p) car(car(p))
#define cadr(p) car(cdr(p))
#define cdar(p) cdr(car(p))
#define cddr(p) cdr(cdr(p))
#define cadar(p) car(cdr(car(p)))
#define caddr(p) car(cdr(cdr(p)))
#define cdaar(p) cdr(car(car(p)))
#define cadaar(p) car(cdr(car(car(p))))
#define cadddr(p) car(cdr(cdr(cdr(p))))
#define cddddr(p) cdr(cdr(cdr(cdr(p))))
#if USE_CHAR_CLASSIFIERS
static INLINE int Cisalpha(int c) { return isascii(c) && isalpha(c); }
static INLINE int Cisdigit(int c) { return isascii(c) && isdigit(c); }
static INLINE int Cisspace(int c) { return isascii(c) && isspace(c); }
static INLINE int Cisupper(int c) { return isascii(c) && isupper(c); }
static INLINE int Cislower(int c) { return isascii(c) && islower(c); }
#endif
#if USE_ASCII_NAMES
static const char *charnames[32]={
"nul",
"soh",
"stx",
"etx",
"eot",
"enq",
"ack",
"bel",
"bs",
"ht",
"lf",
"vt",
"ff",
"cr",
"so",
"si",
"dle",
"dc1",
"dc2",
"dc3",
"dc4",
"nak",
"syn",
"etb",
"can",
"em",
"sub",
"esc",
"fs",
"gs",
"rs",
"us"
};
static int is_ascii_name(const char *name, int *pc) {
int i;
for(i=0; i<32; i++) {
if(stricmp(name,charnames[i])==0) {
*pc=i;
return 1;
}
}
if(stricmp(name,"del")==0) {
*pc=127;
return 1;
}
return 0;
}
#endif
static int file_push(scheme *sc, const char *fname);
static void file_pop(scheme *sc);
static int file_interactive(scheme *sc);
static INLINE int is_one_of(char *s, int c);
static int alloc_cellseg(scheme *sc, int n);
static long binary_decode(const char *s);
static INLINE pointer get_cell(scheme *sc, pointer a, pointer b);
static pointer _get_cell(scheme *sc, pointer a, pointer b);
static pointer reserve_cells(scheme *sc, int n);
static pointer get_consecutive_cells(scheme *sc, int n);
static pointer find_consecutive_cells(scheme *sc, int n);
static void finalize_cell(scheme *sc, pointer a);
static int count_consecutive_cells(pointer x, int needed);
static pointer find_slot_in_env(scheme *sc, pointer env, pointer sym, int all);
static pointer mk_number(scheme *sc, num n);
static char *store_string(scheme *sc, int len, const char *str, char fill);
static pointer mk_vector(scheme *sc, int len);
static pointer mk_atom(scheme *sc, char *q);
static pointer mk_sharp_const(scheme *sc, char *name);
static pointer mk_port(scheme *sc, port *p);
static pointer port_from_filename(scheme *sc, const char *fn, int prop);
static pointer port_from_file(scheme *sc, FILE *, int prop);
static pointer port_from_string(scheme *sc, char *start, char *past_the_end, int prop);
static port *port_rep_from_filename(scheme *sc, const char *fn, int prop);
static port *port_rep_from_file(scheme *sc, FILE *, int prop);
static port *port_rep_from_string(scheme *sc, char *start, char *past_the_end, int prop);
static void port_close(scheme *sc, pointer p, int flag);
static void mark(pointer a);
static void gc(scheme *sc, pointer a, pointer b);
static int basic_inchar(port *pt);
static int inchar(scheme *sc);
static void backchar(scheme *sc, int c);
static char *readstr_upto(scheme *sc, char *delim);
static pointer readstrexp(scheme *sc);
static INLINE int skipspace(scheme *sc);
static int token(scheme *sc);
static void printslashstring(scheme *sc, char *s, int len);
static void atom2str(scheme *sc, pointer l, int f, char **pp, int *plen);
static void printatom(scheme *sc, pointer l, int f);
static pointer mk_proc(scheme *sc, enum scheme_opcodes op);
static pointer mk_closure(scheme *sc, pointer c, pointer e);
static pointer mk_continuation(scheme *sc, pointer d);
static pointer reverse(scheme *sc, pointer a);
static pointer reverse_in_place(scheme *sc, pointer term, pointer list);
static pointer append(scheme *sc, pointer a, pointer b);
static void dump_stack_mark(scheme *);
static pointer opexe_0(scheme *sc, enum scheme_opcodes op);
static pointer opexe_1(scheme *sc, enum scheme_opcodes op);
static pointer opexe_2(scheme *sc, enum scheme_opcodes op);
static pointer opexe_3(scheme *sc, enum scheme_opcodes op);
static pointer opexe_4(scheme *sc, enum scheme_opcodes op);
static pointer opexe_5(scheme *sc, enum scheme_opcodes op);
static pointer opexe_6(scheme *sc, enum scheme_opcodes op);
static void Eval_Cycle(scheme *sc, enum scheme_opcodes op);
static void assign_syntax(scheme *sc, char *name);
static int syntaxnum(pointer p);
static void assign_proc(scheme *sc, enum scheme_opcodes, char *name);
#define num_ivalue(n) (n.is_fixnum?(n).value.ivalue:(long)(n).value.rvalue)
#define num_rvalue(n) (!n.is_fixnum?(n).value.rvalue:(double)(n).value.ivalue)
static num num_add(num a, num b) {
num ret;
ret.is_fixnum=a.is_fixnum && b.is_fixnum;
if(ret.is_fixnum) {
ret.value.ivalue= a.value.ivalue+b.value.ivalue;
} else {
ret.value.rvalue=num_rvalue(a)+num_rvalue(b);
}
return ret;
}
static num num_mul(num a, num b) {
num ret;
ret.is_fixnum=a.is_fixnum && b.is_fixnum;
if(ret.is_fixnum) {
ret.value.ivalue= a.value.ivalue*b.value.ivalue;
} else {
ret.value.rvalue=num_rvalue(a)*num_rvalue(b);
}
return ret;
}
static num num_div(num a, num b) {
num ret;
ret.is_fixnum=a.is_fixnum && b.is_fixnum && a.value.ivalue%b.value.ivalue==0;
if(ret.is_fixnum) {
ret.value.ivalue= a.value.ivalue/b.value.ivalue;
} else {
ret.value.rvalue=num_rvalue(a)/num_rvalue(b);
}
return ret;
}
static num num_intdiv(num a, num b) {
num ret;
ret.is_fixnum=a.is_fixnum && b.is_fixnum;
if(ret.is_fixnum) {
ret.value.ivalue= a.value.ivalue/b.value.ivalue;
} else {
ret.value.rvalue=num_rvalue(a)/num_rvalue(b);
}
return ret;
}
static num num_sub(num a, num b) {
num ret;
ret.is_fixnum=a.is_fixnum && b.is_fixnum;
if(ret.is_fixnum) {
ret.value.ivalue= a.value.ivalue-b.value.ivalue;
} else {
ret.value.rvalue=num_rvalue(a)-num_rvalue(b);
}
return ret;
}
static num num_rem(num a, num b) {
num ret;
long e1, e2, res;
ret.is_fixnum=a.is_fixnum && b.is_fixnum;
e1=num_ivalue(a);
e2=num_ivalue(b);
res=e1%e2;
/* modulo should have same sign as second operand */
if (res > 0) {
if (e1 < 0) {
res -= labs(e2);
}
} else if (res < 0) {
if (e1 > 0) {
res += labs(e2);
}
}
ret.value.ivalue=res;
return ret;
}
static num num_mod(num a, num b) {
num ret;
long e1, e2, res;
ret.is_fixnum=a.is_fixnum && b.is_fixnum;
e1=num_ivalue(a);
e2=num_ivalue(b);
res=e1%e2;
if(res*e2<0) { /* modulo should have same sign as second operand */
e2=labs(e2);
if(res>0) {
res-=e2;
} else {
res+=e2;
}
}
ret.value.ivalue=res;
return ret;
}
static int num_eq(num a, num b) {
int ret;
int is_fixnum=a.is_fixnum && b.is_fixnum;
if(is_fixnum) {
ret= a.value.ivalue==b.value.ivalue;
} else {
ret=num_rvalue(a)==num_rvalue(b);
}
return ret;
}
static int num_gt(num a, num b) {
int ret;
int is_fixnum=a.is_fixnum && b.is_fixnum;
if(is_fixnum) {
ret= a.value.ivalue>b.value.ivalue;
} else {
ret=num_rvalue(a)>num_rvalue(b);
}
return ret;
}
static int num_ge(num a, num b) {
return !num_lt(a,b);
}
static int num_lt(num a, num b) {
int ret;
int is_fixnum=a.is_fixnum && b.is_fixnum;
if(is_fixnum) {
ret= a.value.ivalue<b.value.ivalue;
} else {
ret=num_rvalue(a)<num_rvalue(b);
}
return ret;
}
static int num_le(num a, num b) {
return !num_gt(a,b);
}
#if USE_MATH
/* Round to nearest. Round to even if midway */
static double round_per_R5RS(double x) {
double fl=floor(x);
double ce=ceil(x);
double dfl=x-fl;
double dce=ce-x;
if(dfl>dce) {
return ce;
} else if(dfl<dce) {
return fl;
} else {
if(fmod(fl,2.0)==0.0) { /* I imagine this holds */
return fl;
} else {
return ce;
}
}
}
#endif
static int is_zero_double(double x) {
return x<DBL_MIN && x>-DBL_MIN;
}
static long binary_decode(const char *s) {
long x=0;
while(*s!=0 && (*s=='1' || *s=='0')) {
x<<=1;
x+=*s-'0';
s++;
}
return x;
}
/* allocate new cell segment */
static int alloc_cellseg(scheme *sc, int n) {
pointer newp;
pointer last;
pointer p;
char *cp;
long i;
int k;
int adj=ADJ;
if(adj<sizeof(struct cell)) {
adj=sizeof(struct cell);
}
for (k = 0; k < n; k++) {
if (sc->last_cell_seg >= CELL_NSEGMENT - 1)
return k;
cp = (char*) sc->malloc(CELL_SEGSIZE * sizeof(struct cell)+adj);
if (cp == 0)
return k;
i = ++sc->last_cell_seg ;
sc->alloc_seg[i] = cp;
/* adjust in TYPE_BITS-bit boundary */
if(((unsigned long)cp)%adj!=0) {
cp=(char*)(adj*((unsigned long)cp/adj+1));
}
/* insert new segment in address order */
newp=(pointer)cp;
sc->cell_seg[i] = newp;
while (i > 0 && sc->cell_seg[i - 1] > sc->cell_seg[i]) {
p = sc->cell_seg[i];
sc->cell_seg[i] = sc->cell_seg[i - 1];
sc->cell_seg[--i] = p;
}
sc->fcells += CELL_SEGSIZE;
last = newp + CELL_SEGSIZE - 1;
for (p = newp; p <= last; p++) {
typeflag(p) = 0;
cdr(p) = p + 1;
car(p) = sc->NIL;
}
/* insert new cells in address order on free list */
if (sc->free_cell == sc->NIL || p < sc->free_cell) {
cdr(last) = sc->free_cell;
sc->free_cell = newp;
} else {
p = sc->free_cell;
while (cdr(p) != sc->NIL && newp > cdr(p))
p = cdr(p);
cdr(last) = cdr(p);
cdr(p) = newp;
}
}
return n;
}
static INLINE pointer get_cell_x(scheme *sc, pointer a, pointer b) {
if (sc->free_cell != sc->NIL) {
pointer x = sc->free_cell;
sc->free_cell = cdr(x);
--sc->fcells;
return (x);
}
return _get_cell (sc, a, b);
}
/* get new cell. parameter a, b is marked by gc. */
static pointer _get_cell(scheme *sc, pointer a, pointer b) {
pointer x;
if(sc->no_memory) {
return sc->sink;
}
if (sc->free_cell == sc->NIL) {
const int min_to_be_recovered = sc->last_cell_seg*8;
gc(sc,a, b);
if (sc->fcells < min_to_be_recovered
|| sc->free_cell == sc->NIL) {
/* if only a few recovered, get more to avoid fruitless gc's */
if (!alloc_cellseg(sc,1) && sc->free_cell == sc->NIL) {
sc->no_memory=1;
return sc->sink;
}
}
}
x = sc->free_cell;
sc->free_cell = cdr(x);
--sc->fcells;
return (x);
}
/* make sure that there is a given number of cells free */
static pointer reserve_cells(scheme *sc, int n) {
if(sc->no_memory) {
return sc->NIL;
}
/* Are there enough cells available? */
if (sc->fcells < n) {
/* If not, try gc'ing some */
gc(sc, sc->NIL, sc->NIL);
if (sc->fcells < n) {
/* If there still aren't, try getting more heap */
if (!alloc_cellseg(sc,1)) {
sc->no_memory=1;
return sc->NIL;
}
}
if (sc->fcells < n) {
/* If all fail, report failure */
sc->no_memory=1;
return sc->NIL;
}
}
return (sc->T);
}
static pointer get_consecutive_cells(scheme *sc, int n) {
pointer x;
if(sc->no_memory) { return sc->sink; }
/* Are there any cells available? */
x=find_consecutive_cells(sc,n);
if (x != sc->NIL) { return x; }
/* If not, try gc'ing some */
gc(sc, sc->NIL, sc->NIL);
x=find_consecutive_cells(sc,n);
if (x != sc->NIL) { return x; }
/* If there still aren't, try getting more heap */
if (!alloc_cellseg(sc,1))
{
sc->no_memory=1;
return sc->sink;
}
x=find_consecutive_cells(sc,n);
if (x != sc->NIL) { return x; }
/* If all fail, report failure */
sc->no_memory=1;
return sc->sink;
}
static int count_consecutive_cells(pointer x, int needed) {
int n=1;
while(cdr(x)==x+1) {
x=cdr(x);
n++;
if(n>needed) return n;
}
return n;
}
static pointer find_consecutive_cells(scheme *sc, int n) {
pointer *pp;
int cnt;
pp=&sc->free_cell;
while(*pp!=sc->NIL) {
cnt=count_consecutive_cells(*pp,n);
if(cnt>=n) {
pointer x=*pp;
*pp=cdr(*pp+n-1);
sc->fcells -= n;
return x;
}
pp=&cdr(*pp+cnt-1);
}
return sc->NIL;
}
/* To retain recent allocs before interpreter knows about them -
Tehom */
static void push_recent_alloc(scheme *sc, pointer recent, pointer extra)
{
pointer holder = get_cell_x(sc, recent, extra);
typeflag(holder) = T_PAIR | T_IMMUTABLE;
car(holder) = recent;
cdr(holder) = car(sc->sink);
car(sc->sink) = holder;
}
static pointer get_cell(scheme *sc, pointer a, pointer b)
{
pointer cell = get_cell_x(sc, a, b);
/* For right now, include "a" and "b" in "cell" so that gc doesn't
think they are garbage. */
/* Tentatively record it as a pair so gc understands it. */
typeflag(cell) = T_PAIR;
car(cell) = a;
cdr(cell) = b;
push_recent_alloc(sc, cell, sc->NIL);
return cell;
}
static pointer get_vector_object(scheme *sc, int len, pointer init)
{
pointer cells = get_consecutive_cells(sc,len/2+len%2+1);
if(sc->no_memory) { return sc->sink; }
/* Record it as a vector so that gc understands it. */
typeflag(cells) = (T_VECTOR | T_ATOM);
ivalue_unchecked(cells)=len;
set_num_integer(cells);
fill_vector(cells,init);
push_recent_alloc(sc, cells, sc->NIL);
return cells;
}
static INLINE void ok_to_freely_gc(scheme *sc)
{
car(sc->sink) = sc->NIL;
}
#if defined TSGRIND
static void check_cell_alloced(pointer p, int expect_alloced)
{
/* Can't use putstr(sc,str) because callers have no access to
sc. */
if(typeflag(p) & !expect_alloced)
{
fprintf(stderr,"Cell is already allocated!\n");
}
if(!(typeflag(p)) & expect_alloced)
{
fprintf(stderr,"Cell is not allocated!\n");
}
}
static void check_range_alloced(pointer p, int n, int expect_alloced)
{
int i;
for(i = 0;i<n;i++)
{ (void)check_cell_alloced(p+i,expect_alloced); }
}
#endif
/* Medium level cell allocation */
/* get new cons cell */
pointer _cons(scheme *sc, pointer a, pointer b, int immutable) {
pointer x = get_cell(sc,a, b);
typeflag(x) = T_PAIR;
if(immutable) {
setimmutable(x);
}
car(x) = a;
cdr(x) = b;
return (x);
}
/* ========== oblist implementation ========== */
#ifndef USE_OBJECT_LIST
static int hash_fn(const char *key, int table_size);
static pointer oblist_initial_value(scheme *sc)
{
return mk_vector(sc, 461); /* probably should be bigger */
}
/* returns the new symbol */
static pointer oblist_add_by_name(scheme *sc, const char *name)
{
pointer x;
int location;
x = immutable_cons(sc, mk_string(sc, name), sc->NIL);
typeflag(x) = T_SYMBOL;
setimmutable(car(x));
location = hash_fn(name, ivalue_unchecked(sc->oblist));
set_vector_elem(sc->oblist, location,
immutable_cons(sc, x, vector_elem(sc->oblist, location)));
return x;
}
static INLINE pointer oblist_find_by_name(scheme *sc, const char *name)
{
int location;
pointer x;
char *s;
location = hash_fn(name, ivalue_unchecked(sc->oblist));
for (x = vector_elem(sc->oblist, location); x != sc->NIL; x = cdr(x)) {
s = symname(car(x));
/* case-insensitive, per R5RS section 2. */
if(stricmp(name, s) == 0) {
return car(x);
}
}
return sc->NIL;
}
static pointer oblist_all_symbols(scheme *sc)
{
int i;
pointer x;
pointer ob_list = sc->NIL;
for (i = 0; i < ivalue_unchecked(sc->oblist); i++) {
for (x = vector_elem(sc->oblist, i); x != sc->NIL; x = cdr(x)) {
ob_list = cons(sc, x, ob_list);
}
}
return ob_list;
}
#else
static pointer oblist_initial_value(scheme *sc)
{
return sc->NIL;
}
static INLINE pointer oblist_find_by_name(scheme *sc, const char *name)
{
pointer x;
char *s;
for (x = sc->oblist; x != sc->NIL; x = cdr(x)) {
s = symname(car(x));
/* case-insensitive, per R5RS section 2. */
if(stricmp(name, s) == 0) {
return car(x);
}
}
return sc->NIL;
}
/* returns the new symbol */
static pointer oblist_add_by_name(scheme *sc, const char *name)
{
pointer x;
x = immutable_cons(sc, mk_string(sc, name), sc->NIL);
typeflag(x) = T_SYMBOL;
setimmutable(car(x));
sc->oblist = immutable_cons(sc, x, sc->oblist);
return x;
}
static pointer oblist_all_symbols(scheme *sc)
{
return sc->oblist;
}
#endif
static pointer mk_port(scheme *sc, port *p) {
pointer x = get_cell(sc, sc->NIL, sc->NIL);
typeflag(x) = T_PORT|T_ATOM;
x->_object._port=p;
return (x);
}
pointer mk_foreign_func(scheme *sc, foreign_func f) {
pointer x = get_cell(sc, sc->NIL, sc->NIL);
typeflag(x) = (T_FOREIGN | T_ATOM);
x->_object._ff=f;
return (x);
}
INTERFACE pointer mk_character(scheme *sc, int c) {
pointer x = get_cell(sc,sc->NIL, sc->NIL);
typeflag(x) = (T_CHARACTER | T_ATOM);
ivalue_unchecked(x)= c;
set_num_integer(x);
return (x);
}
/* get number atom (integer) */
INTERFACE pointer mk_integer(scheme *sc, long num) {
pointer x = get_cell(sc,sc->NIL, sc->NIL);
typeflag(x) = (T_NUMBER | T_ATOM);
ivalue_unchecked(x)= num;
set_num_integer(x);
return (x);
}
INTERFACE pointer mk_real(scheme *sc, double n) {
pointer x = get_cell(sc,sc->NIL, sc->NIL);
typeflag(x) = (T_NUMBER | T_ATOM);
rvalue_unchecked(x)= n;
set_num_real(x);
return (x);
}
static pointer mk_number(scheme *sc, num n) {
if(n.is_fixnum) {
return mk_integer(sc,n.value.ivalue);
} else {
return mk_real(sc,n.value.rvalue);
}
}
/* allocate name to string area */
static char *store_string(scheme *sc, int len_str, const char *str, char fill) {
char *q;
q=(char*)sc->malloc(len_str+1);
if(q==0) {
sc->no_memory=1;
return sc->strbuff;
}
if(str!=0) {
snprintf(q, len_str+1, "%s", str);
} else {
memset(q, fill, len_str);
q[len_str]=0;
}
return (q);
}
/* get new string */
INTERFACE pointer mk_string(scheme *sc, const char *str) {
return mk_counted_string(sc,str,strlen(str));
}
INTERFACE pointer mk_counted_string(scheme *sc, const char *str, int len) {
pointer x = get_cell(sc, sc->NIL, sc->NIL);
typeflag(x) = (T_STRING | T_ATOM);
strvalue(x) = store_string(sc,len,str,0);
strlength(x) = len;
return (x);
}
INTERFACE pointer mk_empty_string(scheme *sc, int len, char fill) {
pointer x = get_cell(sc, sc->NIL, sc->NIL);
typeflag(x) = (T_STRING | T_ATOM);
strvalue(x) = store_string(sc,len,0,fill);