/* Runtime library */

# define _GNU_SOURCE 1

# include "runtime.h"
# include "runtime_common.h"
# include "gc.h"

# define __ENABLE_GC__
# ifndef __ENABLE_GC__
# define alloc malloc
# endif

//# define DEBUG_PRINT 1

# ifdef __ENABLE_GC__

/* GC extern invariant for built-in functions */
extern void __pre_gc  ();
extern void __post_gc ();

# else

# define __pre_gc __pre_gc_subst
# define __post_gc __post_gc_subst

void __pre_gc_subst () {}
void __post_gc_subst () {}

# endif
/* end */

static void vfailure (char *s, va_list args) {
    fprintf  (stderr, "*** FAILURE: ");
    vfprintf (stderr, s, args); // vprintf (char *, va_list) <-> printf (char *, ...)
    exit     (255);
}

void failure (char *s, ...) {
    va_list args;

    va_start (args, s);
    vfailure (s, args);
}

void Lassert (void *f, char *s, ...) {
    if (!UNBOX(f)) {
        va_list args;

        va_start (args, s);
        vfailure (s, args);
    }
}

# define ASSERT_BOXED(memo, x)               \
  do if (UNBOXED(x)) failure ("boxed value expected in %s\n", memo); while (0)
# define ASSERT_UNBOXED(memo, x)             \
  do if (!UNBOXED(x)) failure ("unboxed value expected in %s\n", memo); while (0)
# define ASSERT_STRING(memo, x)              \
  do if (!UNBOXED(x) && TAG(TO_DATA(x)->data_header) \
	 != STRING_TAG) failure ("string value expected in %s\n", memo); while (0)

//extern void* alloc    (size_t);
extern void* Bsexp    (int n, ...);
extern int   LtagHash (char*);

void *global_sysargs;

// Gets a raw data_header
extern int LkindOf (void *p) {
    if (UNBOXED(p)) return UNBOXED_TAG;

    return TAG(TO_DATA(p)->data_header);
}

// Compare sexprs tags
extern int LcompareTags (void *p, void *q) {
    data *pd, *qd;

    ASSERT_BOXED ("compareTags, 0", p);
    ASSERT_BOXED ("compareTags, 1", q);

    pd = TO_DATA(p);
    qd = TO_DATA(q);

    if (TAG(pd->data_header) == SEXP_TAG && TAG(qd->data_header) == SEXP_TAG) {
        return
#ifndef DEBUG_PRINT
                BOX((TO_SEXP(p)->tag) - (TO_SEXP(q)->tag));
#else
        BOX((GET_SEXP_TAG(TO_SEXP(p)->data_header)) - (GET_SEXP_TAG(TO_SEXP(p)->data_header)));
#endif
    }
    else failure ("not a sexpr in compareTags: %d, %d\n", TAG(pd->data_header), TAG(qd->data_header));

    return 0; // never happens
}

// Functional synonym for built-in operator ":";
void* Ls__Infix_58 (void *p, void *q) {
    void *res;

    __pre_gc ();

    push_extra_root(&p);
    push_extra_root(&q);
    res = Bsexp (BOX(3), p, q, LtagHash ("cons")); //BOX(848787));
    pop_extra_root(&q);
    pop_extra_root(&p);

    __post_gc ();

    return res;
}

// Functional synonym for built-in operator "!!";
int Ls__Infix_3333 (void *p, void *q) {
    ASSERT_UNBOXED("captured !!:1", p);
    ASSERT_UNBOXED("captured !!:2", q);

    return BOX(UNBOX(p) || UNBOX(q));
}

// Functional synonym for built-in operator "&&";
int Ls__Infix_3838 (void *p, void *q) {
    ASSERT_UNBOXED("captured &&:1", p);
    ASSERT_UNBOXED("captured &&:2", q);

    return BOX(UNBOX(p) && UNBOX(q));
}

// Functional synonym for built-in operator "==";
int Ls__Infix_6161 (void *p, void *q) {
    return BOX(p == q);
}

// Functional synonym for built-in operator "!=";
int Ls__Infix_3361 (void *p, void *q) {
    ASSERT_UNBOXED("captured !=:1", p);
    ASSERT_UNBOXED("captured !=:2", q);

    return BOX(UNBOX(p) != UNBOX(q));
}

// Functional synonym for built-in operator "<=";
int Ls__Infix_6061 (void *p, void *q) {
    ASSERT_UNBOXED("captured <=:1", p);
    ASSERT_UNBOXED("captured <=:2", q);

    return BOX(UNBOX(p) <= UNBOX(q));
}

// Functional synonym for built-in operator "<";
int Ls__Infix_60 (void *p, void *q) {
    ASSERT_UNBOXED("captured <:1", p);
    ASSERT_UNBOXED("captured <:2", q);

    return BOX(UNBOX(p) < UNBOX(q));
}

// Functional synonym for built-in operator ">=";
int Ls__Infix_6261 (void *p, void *q) {
    ASSERT_UNBOXED("captured >=:1", p);
    ASSERT_UNBOXED("captured >=:2", q);

    return BOX(UNBOX(p) >= UNBOX(q));
}

// Functional synonym for built-in operator ">";
int Ls__Infix_62 (void *p, void *q) {
    ASSERT_UNBOXED("captured >:1", p);
    ASSERT_UNBOXED("captured >:2", q);

    return BOX(UNBOX(p) > UNBOX(q));
}

// Functional synonym for built-in operator "+";
int Ls__Infix_43 (void *p, void *q) {
    ASSERT_UNBOXED("captured +:1", p);
    ASSERT_UNBOXED("captured +:2", q);

    return BOX(UNBOX(p) + UNBOX(q));
}

// Functional synonym for built-in operator "-";
int Ls__Infix_45 (void *p, void *q) {
    if (UNBOXED(p)) {
        ASSERT_UNBOXED("captured -:2", q);
        return BOX(UNBOX(p) - UNBOX(q));
    }

    ASSERT_BOXED("captured -:1", q);
    return BOX(p - q);
}

// Functional synonym for built-in operator "*";
int Ls__Infix_42 (void *p, void *q) {
    ASSERT_UNBOXED("captured *:1", p);
    ASSERT_UNBOXED("captured *:2", q);

    return BOX(UNBOX(p) * UNBOX(q));
}

// Functional synonym for built-in operator "/";
int Ls__Infix_47 (void *p, void *q) {
    ASSERT_UNBOXED("captured /:1", p);
    ASSERT_UNBOXED("captured /:2", q);

    return BOX(UNBOX(p) / UNBOX(q));
}

// Functional synonym for built-in operator "%";
int Ls__Infix_37 (void *p, void *q) {
    ASSERT_UNBOXED("captured %:1", p);
    ASSERT_UNBOXED("captured %:2", q);

    return BOX(UNBOX(p) % UNBOX(q));
}

extern int Llength (void *p) {
    ASSERT_BOXED(".length", p);
    return BOX(obj_size_row_ptr(p));
}

static char* chars = "_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'";

extern char* de_hash (int);

extern int LtagHash (char *s) {
    char *p;
    int  h = 0, limit = 0;

    p = s;

    while (*p && limit++ <= 4) {
        char *q = chars;
        int pos = 0;

        for (; *q && *q != *p; q++, pos++);

        if (*q) h = (h << 6) | pos;
        else failure ("tagHash: character not found: %c\n", *p);

        p++;
    }

    if (strcmp (s, de_hash (h)) != 0) {
        failure ("%s <-> %s\n", s, de_hash(h));
    }

    return BOX(h);
}

char* de_hash (int n) {
    //  static char *chars = (char*) BOX (NULL);
    static char buf[6] = {0,0,0,0,0,0};
    char *p = (char *) BOX (NULL);
    p = &buf[5];

#ifdef DEBUG_PRINT
    indent++; print_indent ();
  printf ("de_hash: data_header: %d\n", n); fflush (stdout);
#endif

    *p-- = 0;

    while (n != 0) {
#ifdef DEBUG_PRINT
        print_indent ();
    printf ("char: %c\n", chars [n & 0x003F]); fflush (stdout);
#endif
        *p-- = chars [n & 0x003F];
        n = n >> 6;
    }

#ifdef DEBUG_PRINT
    indent--;
#endif

    return ++p;
}

typedef struct {
    char *contents;
    int ptr;
    int len;
} StringBuf;

static StringBuf stringBuf;

# define STRINGBUF_INIT 128

static void createStringBuf () {
    stringBuf.contents = (char*) malloc (STRINGBUF_INIT);
    memset(stringBuf.contents, 0, STRINGBUF_INIT);
    stringBuf.ptr      = 0;
    stringBuf.len      = STRINGBUF_INIT;
}

static void deleteStringBuf () {
    free (stringBuf.contents);
}

static void extendStringBuf () {
    int len = stringBuf.len << 1;

    stringBuf.contents = (char*) realloc (stringBuf.contents, len);
    stringBuf.len      = len;
}

static void vprintStringBuf (char *fmt, va_list args) {
    int     written = 0,
            rest    = 0;
    char   *buf     = (char*) BOX(NULL);
    va_list vsnargs;

    again:
    va_copy (vsnargs, args);

    buf     = &stringBuf.contents[stringBuf.ptr];
    rest    = stringBuf.len - stringBuf.ptr;

    written = vsnprintf (buf, rest, fmt, vsnargs);

    va_end(vsnargs);

    if (written >= rest) {
        extendStringBuf ();
        goto again;
    }

    stringBuf.ptr += written;
}

static void printStringBuf (char *fmt, ...) {
    va_list args;

    va_start (args, fmt);
    vprintStringBuf (fmt, args);
}

//int is_valid_heap_pointer (void *p);

static void printValue (void *p) {
    data *a = (data*) BOX(NULL);
    int i   = BOX(0);
    if (UNBOXED(p)) printStringBuf ("%d", UNBOX(p));
    else {
        if (!is_valid_heap_pointer(p)) {
            printStringBuf ("0x%x", p);
            return;
        }

        a = TO_DATA(p);

        switch (TAG(a->data_header)) {
            case STRING_TAG:
                printStringBuf ("\"%s\"", a->contents);
                break;

            case CLOSURE_TAG:
                printStringBuf ("<closure ");
                for (i = 0; i < LEN(a->data_header); i++) {
                    if (i) printValue ((void*)((int*) a->contents)[i]);
                    else printStringBuf ("0x%x", (void*)((int*) a->contents)[i]);
                    if (i != LEN(a->data_header) - 1) printStringBuf (", ");
                }
                printStringBuf (">");
                break;

            case ARRAY_TAG:
                printStringBuf ("[");
                for (i = 0; i < LEN(a->data_header); i++) {
                    printValue ((void*)((int*) a->contents)[i]);
                    if (i != LEN(a->data_header) - 1) printStringBuf (", ");
                }
                printStringBuf ("]");
                break;

            case SEXP_TAG: {
#ifndef DEBUG_PRINT
                char * tag = de_hash (TO_SEXP(p)->tag);
#else
                char * data_header = de_hash (GET_SEXP_TAG(TO_SEXP(p)->data_header));
#endif

                if (strcmp (tag, "cons") == 0) {
                    data *b = a;
                    printStringBuf ("{");
                    while (LEN(a->data_header)) {
                        printValue ((void*)((int*) b->contents)[0]);
                        b = (data*)((int*) b->contents)[1];
                        if (! UNBOXED(b)) {
                            printStringBuf (", ");
                            b = TO_DATA(b);
                        }
                        else break;
                    }
                    printStringBuf ("}");
                }
                else {
                    printStringBuf ("%s", tag);
                    if (LEN(a->data_header)) {
                        printStringBuf (" (");
                        for (i = 0; i < LEN(a->data_header); i++) {
                            printValue ((void*)((int*) a->contents)[i]);
                            if (i != LEN(a->data_header) - 1) printStringBuf (", ");
                        }
                        printStringBuf (")");
                    }
                }
            }
                break;

            default:
                printStringBuf ("*** invalid data_header: 0x%x ***", TAG(a->data_header));
        }
    }
}

static void stringcat (void *p) {
    data *a;
    int i;

    if (UNBOXED(p)) ;
    else {
        a = TO_DATA(p);

        switch (TAG(a->data_header)) {
            case STRING_TAG:
                printStringBuf ("%s", a->contents);
                break;

            case SEXP_TAG: {
#ifndef DEBUG_PRINT
                char * tag = de_hash (TO_SEXP(p)->tag);
#else
                char * data_header = de_hash (GET_SEXP_TAG(TO_SEXP(p)->data_header));
#endif
                if (strcmp (tag, "cons") == 0) {
                    data *b = a;

                    while (LEN(a->data_header)) {
                        stringcat ((void*)((int*) b->contents)[0]);
                        b = (data*)((int*) b->contents)[1];
                        if (! UNBOXED(b)) {
                            b = TO_DATA(b);
                        }
                        else break;
                    }
                }
                else printStringBuf ("*** non-list data_header: %s ***", tag);
            }
                break;

            default:
                printStringBuf ("*** invalid data_header: 0x%x ***", TAG(a->data_header));
        }
    }
}

extern int Luppercase (void *v) {
    ASSERT_UNBOXED("Luppercase:1", v);
    return BOX(toupper ((int) UNBOX(v)));
}

extern int Llowercase (void *v) {
    ASSERT_UNBOXED("Llowercase:1", v);
    return BOX(tolower ((int) UNBOX(v)));
}

extern int LmatchSubString (char *subj, char *patt, int pos) {
    data *p = TO_DATA(patt), *s = TO_DATA(subj);
    int   n;

    ASSERT_STRING("matchSubString:1", subj);
    ASSERT_STRING("matchSubString:2", patt);
    ASSERT_UNBOXED("matchSubString:3", pos);

    n = LEN (p->data_header);

    if (n + UNBOX(pos) > LEN(s->data_header))
        return BOX(0);

    return BOX(strncmp (subj + UNBOX(pos), patt, n) == 0);
}

extern void* Lsubstring (void *subj, int p, int l) {
    data *d = TO_DATA(subj);
    int pp = UNBOX (p), ll = UNBOX (l);

    ASSERT_STRING("substring:1", subj);
    ASSERT_UNBOXED("substring:2", p);
    ASSERT_UNBOXED("substring:3", l);

    if (pp + ll <= LEN(d->data_header)) {
        data *r;

        __pre_gc ();

        push_extra_root (&subj);
        r = (data*) alloc_string(ll);
        pop_extra_root (&subj);

        strncpy (r->contents, (char*) subj + pp, ll);

        __post_gc ();

        return r->contents;
    }

    failure ("substring: index out of bounds (position=%d, length=%d, \
            subject length=%d)", pp, ll, LEN(d->data_header));
}

extern struct re_pattern_buffer *Lregexp (char *regexp) {
    regex_t *b = (regex_t*) malloc (sizeof (regex_t));

    /* printf ("regexp: %s,\test_small_tree_compaction%x\n", regexp, b); */

    memset (b, 0, sizeof (regex_t));

    int n = (int) re_compile_pattern (regexp, strlen (regexp), b);

    if (n != 0) {
        failure ("%", strerror (n));
    };

    return b;
}

extern int LregexpMatch (struct re_pattern_buffer *b, char *s, int pos) {
    int res;

    ASSERT_BOXED("regexpMatch:1", b);
    ASSERT_STRING("regexpMatch:2", s);
    ASSERT_UNBOXED("regexpMatch:3", pos);

    res = re_match (b, s, LEN(TO_DATA(s)->data_header), UNBOX(pos), 0);

    /* printf ("regexpMatch %x: %s, res=%d\n", b, s+UNBOX(pos), res); */

    if (res) {
        return BOX (res);
    }

    return BOX (res);
}

extern void* Bstring (void*);

void *Lclone (void *p) {
    data *obj;
    sexp *sobj;
    void* res;
    int n;
#ifdef DEBUG_PRINT
    register int * ebp asm ("ebp");
  indent++; print_indent ();
  printf ("Lclone arg: %p %p\n", &p, p); fflush (stdout);
#endif
    __pre_gc ();

    if (UNBOXED(p)) return p;
    else {
        data *a = TO_DATA(p);
        int t   = TAG(a->data_header), l = LEN(a->data_header);

        push_extra_root (&p);
        switch (t) {
            case STRING_TAG:
#ifdef DEBUG_PRINT
                print_indent ();
      printf ("Lclone: string1 &p=%p p=%p\n", &p, p); fflush (stdout);
#endif
                res = Bstring (TO_DATA(p)->contents);
#ifdef DEBUG_PRINT
                print_indent ();
      printf ("Lclone: string2 %p %p\n", &p, p); fflush (stdout);
#endif
                break;

            case ARRAY_TAG:
#ifdef DEBUG_PRINT
                print_indent ();
                printf ("Lclone: array &p=%p p=%p ebp=%p\n", &p, p, ebp); fflush (stdout);
#endif
                obj = (data *) alloc_array(l);
                memcpy(obj, TO_DATA(p), array_size(l));
                res = (void *) obj->contents;
                break;
            case CLOSURE_TAG:
#ifdef DEBUG_PRINT
                print_indent ();
                printf ("Lclone: closure &p=%p p=%p ebp=%p\n", &p, p, ebp); fflush (stdout);
#endif
                obj = (data *) alloc_closure(l);
                memcpy (obj, TO_DATA(p), closure_size(l));
                res = (void*) (obj->contents);
                break;

            case SEXP_TAG:
#ifdef DEBUG_PRINT
                print_indent (); printf ("Lclone: sexp\n"); fflush (stdout);
#endif
                sobj = (sexp*) alloc_sexp(l);
                memcpy (sobj, TO_SEXP(p), sexp_size(l));
                res = (void*) sobj->contents.contents;
                break;

            default:
                failure ("invalid data_header %d in clone *****\n", t);
        }
        pop_extra_root (&p);
    }
#ifdef DEBUG_PRINT
    print_indent (); printf ("Lclone ends1\n"); fflush (stdout);
#endif

    __post_gc ();
#ifdef DEBUG_PRINT
    print_indent ();
  printf ("Lclone ends2\n"); fflush (stdout);
  indent--;
#endif
    return res;
}

# define HASH_DEPTH 3
# define HASH_APPEND(acc, x) (((acc + (unsigned) x) << (WORD_SIZE / 2)) | ((acc + (unsigned) x) >> (WORD_SIZE / 2)))

int inner_hash (int depth, unsigned acc, void *p) {
    if (depth > HASH_DEPTH) return acc;

    if (UNBOXED(p)) return HASH_APPEND(acc, UNBOX(p));
    else if (is_valid_heap_pointer (p)) {
        data *a = TO_DATA(p);
        int t = TAG(a->data_header), l = LEN(a->data_header), i;

        acc = HASH_APPEND(acc, t);
        acc = HASH_APPEND(acc, l);

        switch (t) {
            case STRING_TAG: {
                char *p = a->contents;

                while (*p) {
                    int n = (int) *p++;
                    acc = HASH_APPEND(acc, n);
                }

                return acc;
            }

            case CLOSURE_TAG:
                acc = HASH_APPEND(acc, ((void**) a->contents)[0]);
                i = 1;
                break;

            case ARRAY_TAG:
                i = 0;
                break;

            case SEXP_TAG: {
#ifndef DEBUG_PRINT
                int ta = TO_SEXP(p)->tag;
#else
                int ta = GET_SEXP_TAG(TO_SEXP(p)->data_header);
#endif
                acc = HASH_APPEND(acc, ta);
                i = 0;
                break;
            }

            default:
                failure ("invalid data_header %d in hash *****\n", t);
        }

        for (; i<l; i++)
            acc = inner_hash (depth+1, acc, ((void**) a->contents)[i]);

        return acc;
    }
    else return HASH_APPEND(acc, p);
}

extern void* LstringInt (char *b) {
    int n;
    sscanf (b, "%d", &n);
    return (void*) BOX(n);
}

extern int Lhash (void *p) {
    return BOX(0x3fffff & inner_hash (0, 0, p));
}

extern int LflatCompare (void *p, void *q) {
    if (UNBOXED(p)) {
        if (UNBOXED(q)) {
            return BOX (UNBOX(p) - UNBOX(q));
        }

        return -1;
    }
    else if (~UNBOXED(q)) {
        return BOX(p - q);
    }
    else BOX(1);
}

extern int Lcompare (void *p, void *q) {
# define COMPARE_AND_RETURN(x,y) do if (x != y) return BOX(x - y); while (0)

    if (p == q) return BOX(0);

    if (UNBOXED(p)) {
        if (UNBOXED(q)) return BOX(UNBOX(p) - UNBOX(q));
        else return BOX(-1);
    }
    else if (UNBOXED(q)) return BOX(1);
    else {
        if (is_valid_heap_pointer (p)) {
            if (is_valid_heap_pointer (q)) {
                data *a = TO_DATA(p), *b = TO_DATA(q);
                int ta = TAG(a->data_header), tb = TAG(b->data_header);
                int la = LEN(a->data_header), lb = LEN(b->data_header);
                int i;

                COMPARE_AND_RETURN (ta, tb);

                switch (ta) {
                    case STRING_TAG:
                        return BOX(strcmp (a->contents, b->contents));

                    case CLOSURE_TAG:
                        COMPARE_AND_RETURN (((void**) a->contents)[0], ((void**) b->contents)[0]);
                        COMPARE_AND_RETURN (la, lb);
                        i = 1;
                        break;

                    case ARRAY_TAG:
                        COMPARE_AND_RETURN (la, lb);
                        i = 0;
                        break;

                    case SEXP_TAG: {
#ifndef DEBUG_PRINT
                        int ta = TO_SEXP(p)->tag, tb = TO_SEXP(q)->tag;
#else
                        int ta = GET_SEXP_TAG(TO_SEXP(p)->data_header), tb = GET_SEXP_TAG(TO_SEXP(q)->data_header);
#endif
                        COMPARE_AND_RETURN (ta, tb);
                        COMPARE_AND_RETURN (la, lb);
                        i = 0;
                        break;
                    }

                    default:
                        failure ("invalid data_header %d in compare *****\n", ta);
                }

                for (; i<la; i++) {
                    int c = Lcompare (((void**) a->contents)[i], ((void**) b->contents)[i]);
                    if (c != BOX(0)) return BOX(c);
                }

                return BOX(0);
            }
            else return BOX(-1);
        }
        else if (is_valid_heap_pointer (q)) return BOX(1);
        else return BOX (p - q);
    }
}

extern void* Belem (void *p, int i) {
    data *a = (data *)BOX(NULL);

    ASSERT_BOXED(".elem:1", p);
    ASSERT_UNBOXED(".elem:2", i);

    a = TO_DATA(p);
    i = UNBOX(i);

    if (TAG(a->data_header) == STRING_TAG) {
        return (void*) BOX(a->contents[i]);
    }

    return (void*) ((int*) a->contents)[i];
}

extern void* LmakeArray (int length) {
    data *r;
    int n, *p;

    ASSERT_UNBOXED("makeArray:1", length);

    __pre_gc ();

    n = UNBOX(length);
    r = (data*) alloc_array(n);

    p = (int*) r->contents;
    while (n--) *p++ = BOX(0);

    __post_gc ();

    return r->contents;
}

extern void* LmakeString (int length) {
    int   n = UNBOX(length);
    data *r;

    ASSERT_UNBOXED("makeString", length);

    __pre_gc () ;

    r = (data*) alloc_string(n); // '\0' in the end of the string is taken into account

    __post_gc();

    return r->contents;
}

extern void* Bstring (void *p) {
    int   n = strlen (p);
    void *s = NULL;

    __pre_gc ();
#ifdef DEBUG_PRINT
    indent++; print_indent ();
    printf ("Bstring: call LmakeString %s %p %p %p %i\n", p, &p, p, s, n);
    fflush(stdout);
#endif
    push_extra_root (&p);
    s = LmakeString (BOX(n));
    pop_extra_root(&p);
#ifdef DEBUG_PRINT
    print_indent ();
    printf ("\tBstring: call strncpy: %p %p %p %i\n", &p, p, s, n); fflush(stdout);
#endif
    strncpy ((char*)s, p, n + 1); // +1 because of '\0' in the end of C-strings
#ifdef DEBUG_PRINT
    print_indent ();
    printf ("\tBstring: ends\n"); fflush(stdout);
    indent--;
#endif
    __post_gc ();

    return s;
}

extern void* Lstringcat (void *p) {
    void *s;

    /* ASSERT_BOXED("stringcat", p); */

    __pre_gc ();

    createStringBuf ();
    stringcat (p);

    push_extra_root(&p);
    s = Bstring (stringBuf.contents);
    pop_extra_root(&p);

    deleteStringBuf ();

    __post_gc ();

    return s;
}

extern void* Lstring (void *p) {
    void *s = (void *) BOX (NULL);

    __pre_gc () ;

    createStringBuf ();
    printValue (p);

    push_extra_root(&p);
    s = Bstring (stringBuf.contents);
    pop_extra_root(&p);

    deleteStringBuf ();

    __post_gc ();

    return s;
}

extern void* Bclosure (int bn, void *entry, ...) {
    va_list args;
    int     i, ai;
    register int * ebp asm ("ebp");
    size_t  *argss;
    data    *r;
    int     n = UNBOX(bn);

    __pre_gc ();
#ifdef DEBUG_PRINT
    indent++; print_indent ();
  printf ("Bclosure: create n = %d\n", n); fflush(stdout);
#endif
    argss = (ebp + 12);
    for (i = 0; i<n; i++, argss++) {
        push_extra_root ((void**)argss);
    }

    r = (data*) alloc_closure(n + 1);

    ((void**) r->contents)[0] = entry;

    va_start(args, entry);

    for (i = 0; i<n; i++) {
        ai = va_arg(args, int);
        ((int*)r->contents)[i+1] = ai;
    }

    va_end(args);

    __post_gc();

    argss--;
    for (i = 0; i<n; i++, argss--) {
        pop_extra_root ((void**)argss);
    }

#ifdef DEBUG_PRINT
    print_indent ();
    printf ("Bclosure: ends\n", n); fflush(stdout);
    indent--;
#endif

    return r->contents;
}

extern void* Barray (int bn, ...) {
    va_list args;
    int     i, ai;
    data    *r;
    int     n = UNBOX(bn);

    __pre_gc ();

#ifdef DEBUG_PRINT
    indent++; print_indent ();
  printf ("Barray: create n = %d\n", n); fflush(stdout);
#endif
    r = (data*) alloc_array(n);

    va_start(args, bn);

    for (i = 0; i<n; i++) {
        ai = va_arg(args, int);
        ((int*)r->contents)[i] = ai;
    }

    va_end(args);

    __post_gc();
#ifdef DEBUG_PRINT
    indent--;
#endif
    return r->contents;
}

#ifdef DEBUG_VERSION
extern memory_chunk heap;
#endif

extern void* Bsexp (int bn, ...) {
    va_list args;
    int     i;
    int     ai;
    size_t *p;
    sexp   *r;
    data   *d;
    int n = UNBOX(bn);

    __pre_gc () ;

#ifdef DEBUG_PRINT
    indent++; print_indent ();
  printf("Bsexp: allocate %zu!\n",sizeof(int) * (n+1)); fflush (stdout);
#endif
    int fields_cnt = n - 1;
    r = (sexp*) alloc_sexp(fields_cnt);
    d = &(r->contents);
    r->tag = 0;

    va_start(args, bn);

    for (i=0; i<n-1; i++) {
        ai = va_arg(args, int);

#ifdef DEBUG_VERSION
        if (!UNBOXED(ai)) {
            assert(is_valid_heap_pointer((size_t *) ai));
        }
#endif

        p = (size_t*) ai;
        ((int*)d->contents)[i] = ai;
    }

    r->tag = UNBOX(va_arg(args, int));

#ifdef DEBUG_PRINT
    r->data_header = SEXP_TAG | ((r->data_header) << 3);
    print_indent ();
    printf("Bsexp: ends\n"); fflush (stdout);
    indent--;
#endif

    va_end(args);

    __post_gc();

    return d->contents;
}

extern int Btag (void *d, int t, int n) {
    data *r;

    if (UNBOXED(d)) return BOX(0);
    else {
        r = TO_DATA(d);
#ifndef DEBUG_PRINT
        return BOX(TAG(r->data_header) == SEXP_TAG && TO_SEXP(d)->tag == UNBOX(t) && LEN(r->data_header) == UNBOX(n));
#else
        return BOX(TAG(r->data_header) == SEXP_TAG &&
               GET_SEXP_TAG(TO_SEXP(d)->data_header) == UNBOX(test_small_tree_compaction) && LEN(r->data_header) == UNBOX(n));
#endif
    }
}

extern int Barray_patt (void *d, int n) {
    data *r;

    if (UNBOXED(d)) return BOX(0);
    else {
        r = TO_DATA(d);
        return BOX(TAG(r->data_header) == ARRAY_TAG && LEN(r->data_header) == UNBOX(n));
    }
}

extern int Bstring_patt (void *x, void *y) {
    data *rx = (data *) BOX (NULL),
            *ry = (data *) BOX (NULL);

    ASSERT_STRING(".string_patt:2", y);

    if (UNBOXED(x)) return BOX(0);
    else {
        rx = TO_DATA(x); ry = TO_DATA(y);

        if (TAG(rx->data_header) != STRING_TAG) return BOX(0);

        return BOX(strcmp (rx->contents, ry->contents) == 0 ? 1 : 0); // TODO: ???
    }
}

extern int Bclosure_tag_patt (void *x) {
    if (UNBOXED(x)) return BOX(0);

    return BOX(TAG(TO_DATA(x)->data_header) == CLOSURE_TAG);
}

extern int Bboxed_patt (void *x) {
    return BOX(UNBOXED(x) ? 0 : 1);
}

extern int Bunboxed_patt (void *x) {
    return BOX(UNBOXED(x) ? 1 : 0);
}

extern int Barray_tag_patt (void *x) {
    if (UNBOXED(x)) return BOX(0);

    return BOX(TAG(TO_DATA(x)->data_header) == ARRAY_TAG);
}

extern int Bstring_tag_patt (void *x) {
    if (UNBOXED(x)) return BOX(0);

    return BOX(TAG(TO_DATA(x)->data_header) == STRING_TAG);
}

extern int Bsexp_tag_patt (void *x) {
    if (UNBOXED(x)) return BOX(0);

    return BOX(TAG(TO_DATA(x)->data_header) == SEXP_TAG);
}

extern void* Bsta (void *v, int i, void *x) {
    if (UNBOXED(i)) {
        ASSERT_BOXED(".sta:3", x);
        //    ASSERT_UNBOXED(".sta:2", i);

        if (TAG(TO_DATA(x)->data_header) == STRING_TAG)((char*) x)[UNBOX(i)] = (char) UNBOX(v);
        else ((int*) x)[UNBOX(i)] = (int) v;

        return v;
    }

    * (void**) x = v;

    return v;
}

static void fix_unboxed (char *s, va_list va) {
    size_t *p = (size_t*)va;
    int i = 0;

    while (*s) {
        if (*s == '%') {
            size_t n = p [i];
            if (UNBOXED (n)) {
                p[i] = UNBOX(n);
            }
            i++;
        }
        s++;
    }
}

extern void Lfailure (char *s, ...) {
    va_list args;

    va_start    (args, s);
    fix_unboxed (s, args);
    vfailure    (s, args);
}

extern void Bmatch_failure (void *v, char *fname, int line, int col) {
    createStringBuf ();
    printValue (v);
    failure ("match failure at %s:%d:%d, value '%s'\n",
             fname, UNBOX(line), UNBOX(col), stringBuf.contents);
}

extern void* /*Lstrcat*/ Li__Infix_4343 (void *a, void *b) {
    data *da = (data*) BOX (NULL);
    data *db = (data*) BOX (NULL);
    data *d  = (data*) BOX (NULL);

    ASSERT_STRING("++:1", a);
    ASSERT_STRING("++:2", b);

    da = TO_DATA(a);
    db = TO_DATA(b);

    __pre_gc () ;

    push_extra_root (&a);
    push_extra_root (&b);
    d = alloc_string(LEN(da->data_header) + LEN(db->data_header));
    pop_extra_root (&b);
    pop_extra_root (&a);

    da = TO_DATA(a);
    db = TO_DATA(b);

    strncpy (d->contents               , da->contents, LEN(da->data_header));
    strncpy (d->contents + LEN(da->data_header), db->contents, LEN(db->data_header));

    d->contents[LEN(da->data_header) + LEN(db->data_header)] = 0;

    __post_gc();

    return d->contents;
}

extern void* Lsprintf (char * fmt, ...) {
    va_list args;
    void *s;

    ASSERT_STRING("sprintf:1", fmt);

    va_start (args, fmt);
    fix_unboxed (fmt, args);

    createStringBuf ();

    vprintStringBuf (fmt, args);

    __pre_gc ();

    push_extra_root ((void**)&fmt);
    s = Bstring (stringBuf.contents);
    pop_extra_root ((void**)&fmt);

    __post_gc ();

    deleteStringBuf ();

    return s;
}

extern void* LgetEnv (char *var) {
    char *e = getenv (var);
    void *s;

    if (e == NULL)
        return (void*) BOX(0); // TODO add (void*) cast?

    __pre_gc ();

    s = Bstring (e);

    __post_gc ();

    return s;
}

extern int Lsystem (char *cmd) {
    return BOX (system (cmd));
}

extern void Lfprintf (FILE *f, char *s, ...) {
    va_list args = (va_list) BOX (NULL);

    ASSERT_BOXED("fprintf:1", f);
    ASSERT_STRING("fprintf:2", s);

    va_start    (args, s);
    fix_unboxed (s, args);

    if (vfprintf (f, s, args) < 0) {
        failure ("fprintf (...): %s\n", strerror (errno));
    }
}

extern void Lprintf (char *s, ...) {
    va_list args = (va_list) BOX (NULL);

    ASSERT_STRING("printf:1", s);

    va_start    (args, s);
    fix_unboxed (s, args);

    if (vprintf (s, args) < 0) {
        failure ("fprintf (...): %s\n", strerror (errno));
    }

    fflush (stdout);
}

extern FILE* Lfopen (char *f, char *m) {
    FILE* h;

    ASSERT_STRING("fopen:1", f);
    ASSERT_STRING("fopen:2", m);

    h = fopen (f, m);

    if (h)
        return h;

    failure ("fopen (\"%s\", \"%s\"): %s, %s, %s\n", f, m, strerror (errno));
}

extern void Lfclose (FILE *f) {
    ASSERT_BOXED("fclose", f);

    fclose (f);
}

extern void* LreadLine () {
    char *buf;

    if (scanf ("%m[^\n]", &buf) == 1) {
        void * s = Bstring (buf);

        getchar ();

        free (buf);
        return s;
    }

    if (errno != 0)
        failure ("readLine (): %s\n", strerror (errno));

    return (void*) BOX (0);
}

extern void* Lfread (char *fname) {
    FILE *f;

    ASSERT_STRING("fread", fname);

    f = fopen (fname, "r");

    if (f) {
        if (fseek (f, 0l, SEEK_END) >= 0) {
            long size = ftell (f);
            void *s   = LmakeString (BOX(size));

            rewind (f);

            if (fread (s, 1, size, f) == size) {
                fclose (f);
                return s;
            }
        }
    }

    failure ("fread (\"%s\"): %s\n", fname, strerror (errno));
}

extern void Lfwrite (char *fname, char *contents) {
    FILE *f;

    ASSERT_STRING("fwrite:1", fname);
    ASSERT_STRING("fwrite:2", contents);

    f = fopen (fname, "w");

    if (f) {
        if (fprintf (f, "%s", contents) < 0);
        else {
            fclose (f);
            return;
        }
    }

    failure ("fwrite (\"%s\"): %s\n", fname, strerror (errno));
}

extern void* Lfexists (char *fname) {
    FILE *f;

    ASSERT_STRING("fexists", fname);

    f = fopen (fname, "r");

    if (f) return (void*) BOX(1); // (void*) cast?

    return (void*) BOX(0); // (void*) cast?
}

extern void* Lfst (void *v) {
    return Belem (v, BOX(0));
}

extern void* Lsnd (void *v) {
    return Belem (v, BOX(1));
}

extern void* Lhd (void *v) {
    return Belem (v, BOX(0));
}

extern void* Ltl (void *v) {
    return Belem (v, BOX(1));
}

/* Lread is an implementation of the "read" construct */
extern int Lread () {
    int result = BOX(0);

    printf ("> ");
    fflush (stdout);
    scanf  ("%d", &result);

    return BOX(result);
}

/* Lwrite is an implementation of the "write" construct */
extern int Lwrite (int n) {
    printf ("%d\n", UNBOX(n));
    fflush (stdout);

    return 0;
}

extern int Lrandom (int n) {
    ASSERT_UNBOXED("Lrandom, 0", n);

    if (UNBOX(n) <= 0) {
        failure ("invalid range in random: %d\n", UNBOX(n));
    }

    return BOX (random () % UNBOX(n));
}

extern int Ltime () {
    struct timespec t;

    clock_gettime (CLOCK_MONOTONIC_RAW, &t);

    return BOX(t.tv_sec * 1000000 + t.tv_nsec / 1000);
}

extern void set_args (int argc, char *argv[]) {
    data *a;
    int n = argc, *p = NULL;
    int i;

    __pre_gc ();

#ifdef DEBUG_PRINT
    indent++; print_indent ();
  printf ("set_args: call: n=%i &p=%p p=%p: ", n, &p, p); fflush(stdout);
  for (i = 0; i < n; i++)
    printf("%s ", argv[i]);
  printf("EE\n");
#endif

    p = LmakeArray (BOX(n));
    push_extra_root ((void**)&p);

    for (i=0; i<n; i++) {
#ifdef DEBUG_PRINT
        print_indent ();
    printf ("set_args: iteration %i %p %p ->\n", i, &p, p); fflush(stdout);
#endif
        ((int*)p) [i] = (int) Bstring (argv[i]);
#ifdef DEBUG_PRINT
        print_indent ();
    printf ("set_args: iteration %i <- %p %p\n", i, &p, p); fflush(stdout);
#endif
    }

    pop_extra_root ((void**)&p);
    __post_gc ();

    global_sysargs = p;
    push_extra_root ((void**)&global_sysargs);
#ifdef DEBUG_PRINT
    print_indent ();
  printf ("set_args: end\n", n, &p, p); fflush(stdout);
  indent--;
#endif
}

/* GC starts here */

static int enable_GC = 1;

extern void LenableGC () {
    enable_GC = 1;
}

extern void LdisableGC () {
    enable_GC = 0;
}