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/*
 * %CopyrightBegin%
 *
 * Copyright Ericsson AB 2005-2017. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * %CopyrightEnd%
 */

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

#include "erl_printf_term.h"
#include "sys.h"
#include "big.h"
#include "erl_map.h"
#include "erl_binary.h"

#define PRINT_CHAR(CNT, FN, ARG, C)					\
do {									\
    int res__ = erts_printf_char((FN), (ARG), (C));			\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

#define PRINT_STRING(CNT, FN, ARG, STR)					\
do {									\
    int res__ = erts_printf_string((FN), (ARG), (STR));			\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

#define PRINT_BUF(CNT, FN, ARG, BUF, LEN)				\
do {									\
    int res__ = erts_printf_buf((FN), (ARG), (char*)(BUF), (LEN));	\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

#define PRINT_POINTER(CNT, FN, ARG, PTR)				\
do {									\
    int res__ = erts_printf_pointer((FN), (ARG), (void *) (PTR));	\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

#define PRINT_UWORD(CNT, FN, ARG, C, P, W, I)				\
do {									\
    int res__ = erts_printf_uword((FN), (ARG), (C), (P), (W), (I));	\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

#define PRINT_SWORD(CNT, FN, ARG, C, P, W, I)				\
do {									\
    int res__ = erts_printf_sword((FN), (ARG), (C), (P), (W), (I));	\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

#define PRINT_DOUBLE(CNT, FN, ARG, C, P, W, I)				\
do {									\
    int res__ = erts_printf_double((FN), (ARG), (C), (P), (W), (I));	\
    if (res__ < 0)							\
	return res__;							\
    (CNT) += res__;							\
} while (0)

/* CTYPE macros */

#define LATIN1

#define IS_DIGIT(c)  ((c) >= '0' && (c) <= '9')
#ifdef LATIN1
#define IS_LOWER(c)  (((c) >= 'a' && (c) <= 'z') \
		      || ((c) >= 128+95 && (c) <= 255 && (c) != 247))
#define IS_UPPER(c)  (((c) >= 'A' && (c) <= 'Z') \
		      || ((c) >= 128+64 && (c) <= 128+94 && (c) != 247-32))
#else
#define IS_LOWER(c)  ((c) >= 'a' && (c) <= 'z')
#define IS_UPPER(c)  ((c) >= 'A' && (c) <= 'Z')
#endif

#define IS_ALNUM(c)  (IS_DIGIT(c) || IS_LOWER(c) || IS_UPPER(c))

/* We don't include 160 (non-breaking space). */
#define IS_SPACE(c)  (c == ' ' || c == '\n' || c == '\t' || c == '\r')

#ifdef LATIN1
#define IS_CNTRL(c)  ((c) < ' ' || (c) == 127 \
		      || ((c) >= 128 && (c) < 128+32))
#else
/* Treat all non-ASCII as control characters */
#define IS_CNTRL(c)  ((c) < ' ' || (c) >= 127)
#endif

#define IS_PRINT(c)  (!IS_CNTRL(c))

/* return 0 if list is not a non-empty flat list of printable characters */

static int
is_printable_string(Eterm list) {
    int len = 0;
    int c;

    while(is_list(list)) {
	Eterm* consp = list_val(list);
	Eterm hd = CAR(consp);

	if (!is_byte(hd))
	    return 0;
	c = signed_val(hd);
	/* IS_PRINT || IS_SPACE would be another way to put it */
	if (IS_CNTRL(c) && !IS_SPACE(c))
	   return 0;
	len++;
	list = CDR(consp);
    }
    if (is_nil(list))
	return len;
    return 0;
}

static int is_printable_ascii(byte* bytep, Uint bytesize, Uint bitoffs)
{
    if (!bitoffs) {
	while (bytesize--) {
	    if (*bytep < ' ' || *bytep >= 127)
		return 0;
	    bytep++;
	}
    } else {
	while (bytesize--) {
	    byte octet = (bytep[0] << bitoffs) | (bytep[1] >> (8-bitoffs));
	    if (octet < ' ' || octet >= 127)
		return 0;
	    bytep++;
	}
    }
    return 1;
}

/* print a atom doing what quoting is necessary */
static int print_atom_name(fmtfn_t fn, void* arg, Eterm atom, long *dcount)
{
    int n, i;
    int res;
    int need_quote;
    int pos;
    byte *s;
    byte *cpos;
    int c;

    res = 0;
    i = atom_val(atom);

    if ((i < 0) || (i >= atom_table_size()) ||  (atom_tab(i) == NULL)) {
	PRINT_STRING(res, fn, arg, "<bad atom index: ");
	PRINT_SWORD(res, fn, arg, 'd', 0, 1, (ErlPfSWord) i);
	PRINT_CHAR(res, fn, arg, '>');
	return res;
    }

    s = atom_tab(i)->name;
    n = atom_tab(i)->len;

    *dcount -= atom_tab(i)->len;

    if (n == 0) {
	PRINT_STRING(res, fn, arg, "''");
	return res;
    }


    need_quote = 0;
    cpos = s;
    pos = n - 1;

    c = *cpos++;
    if (!IS_LOWER(c))
	need_quote++;
    else {
	while (pos--) {
	    c = *cpos++;
	    if (!IS_ALNUM(c) && (c != '_')) {
		need_quote++;
		break;
	    }
	}
    }
    cpos = s;
    pos = n;
    if (need_quote)
	PRINT_CHAR(res, fn, arg, '\'');
    while(pos--) {
	c = *cpos++;
	switch(c) {
	case '\'': PRINT_STRING(res, fn, arg, "\\'"); break;
	case '\\': PRINT_STRING(res, fn, arg, "\\\\"); break;
	case '\n': PRINT_STRING(res, fn, arg, "\\n"); break;
	case '\f': PRINT_STRING(res, fn, arg, "\\f"); break;
	case '\t': PRINT_STRING(res, fn, arg, "\\t"); break;
	case '\r': PRINT_STRING(res, fn, arg, "\\r"); break;
	case '\b': PRINT_STRING(res, fn, arg, "\\b"); break;
	case '\v': PRINT_STRING(res, fn, arg, "\\v"); break;
	default:
	    if (IS_CNTRL(c)) {
		PRINT_CHAR(res, fn, arg, '\\');
		PRINT_UWORD(res, fn, arg, 'o', 1, 3, (ErlPfUWord) c);
	    }
	    else
		PRINT_CHAR(res, fn, arg, (char) c);
	    break;
	}
    }
    if (need_quote)
	PRINT_CHAR(res, fn, arg, '\'');
    return res;
}


#define PRT_BAR                ((Eterm) 0)
#define PRT_COMMA              ((Eterm) 1)
#define PRT_CLOSE_LIST         ((Eterm) 2)
#define PRT_CLOSE_TUPLE        ((Eterm) 3)
#define PRT_ASSOC              ((Eterm) 4)
#define PRT_TERM               ((Eterm) 5)
#define PRT_ONE_CONS           ((Eterm) 6)
#define PRT_PATCH_FUN_SIZE     ((Eterm) 7)
#define PRT_LAST_ARRAY_ELEMENT ((Eterm) 8) /* Note! Must be last... */

#if 0
static char *format_binary(Uint16 x, char *b) {
    int z;
    b[16] = '\0';
    for (z = 0; z < 16; z++) { 
	b[15-z] = ((x>>z) & 0x1) ? '1' : '0'; 
    }
    return b;
}
#endif

static int
print_term(fmtfn_t fn, void* arg, Eterm obj, long *dcount) {
    DECLARE_WSTACK(s);
    int res;
    int i;
    Eterm val;
    Uint32 *ref_num;
    union {
	UWord word;
	Eterm* ptr;
    }popped;
    Eterm* nobj;
    Wterm wobj;

    res = 0;

    goto L_jump_start;

 L_outer_loop:
    while (!WSTACK_ISEMPTY(s)) {
	switch (val = WSTACK_POP(s)) {
	case PRT_COMMA:
	    PRINT_CHAR(res, fn, arg, ',');
	    goto L_outer_loop;
	case PRT_BAR:
	    PRINT_CHAR(res, fn, arg, '|');
	    goto L_outer_loop;
	case PRT_CLOSE_LIST:
	    PRINT_CHAR(res, fn, arg, ']');
	    goto L_outer_loop;
	case PRT_CLOSE_TUPLE:
	    PRINT_CHAR(res, fn, arg, '}');
	    goto L_outer_loop;
	case PRT_ASSOC:
	    PRINT_STRING(res, fn, arg, "=>");
	    goto L_outer_loop;
	default:
	    popped.word = WSTACK_POP(s);

	    switch (val) {
	    case PRT_TERM:
		obj = (Eterm) popped.word;
		break;
	    case PRT_ONE_CONS:
		obj = (Eterm) popped.word;
	    L_print_one_cons:
		{
		    Eterm* cons = list_val(obj);
		    Eterm tl;
		    
		    obj = CAR(cons);
		    tl = CDR(cons);
		    if (is_not_nil(tl)) {
			if (is_list(tl)) {
			    WSTACK_PUSH3(s, tl, PRT_ONE_CONS, PRT_COMMA);
			} else {
			    WSTACK_PUSH3(s, tl, PRT_TERM, PRT_BAR);
			}
		    }
		}
		break;
	    case PRT_LAST_ARRAY_ELEMENT:
		obj = *popped.ptr;
		break;
	    default:		/* PRT_LAST_ARRAY_ELEMENT+1 and upwards */
		obj = *popped.ptr;
	        WSTACK_PUSH3(s, (UWord) (popped.ptr + 1), val-1, PRT_COMMA);
		break;
	    }
	    break;
	}

    L_jump_start:

	if ((*dcount)-- <= 0)
	    goto L_done;

	if (is_CP(obj)) {
	    PRINT_STRING(res, fn, arg, "<cp/header:");
	    PRINT_POINTER(res, fn, arg, cp_val(obj));
	    PRINT_CHAR(res, fn, arg, '>');
	    goto L_done;
	}
	wobj = (Wterm)obj;
	switch (tag_val_def(wobj)) {
	case NIL_DEF:
	    PRINT_STRING(res, fn, arg, "[]");
	    break;
	case ATOM_DEF: {
	    int tres = print_atom_name(fn, arg, obj, dcount);
	    if (tres < 0) {
		res = tres;
		goto L_done;
	    }
	    res += tres;
	    if (*dcount <= 0)
		goto L_done;
	    break;
	}
	case SMALL_DEF:
	    PRINT_SWORD(res, fn, arg, 'd', 0, 1, (ErlPfSWord) signed_val(obj));
	    break;
	case BIG_DEF: {
	    int print_res;
	    char def_buf[64];
	    char *buf, *big_str;
	    Uint sz = (Uint) big_decimal_estimate(wobj);
	    sz++;
	    if (sz <= 64)
		buf = &def_buf[0];
	    else
		buf = erts_alloc(ERTS_ALC_T_TMP, sz);
	    big_str = erts_big_to_string(wobj, buf, sz);
	    print_res = erts_printf_string(fn, arg, big_str);
	    if (buf != &def_buf[0])
		erts_free(ERTS_ALC_T_TMP, (void *) buf);
	    if (print_res < 0) {
		res = print_res;
		goto L_done;
	    }
	    res += print_res;
	    break;
	}
	case REF_DEF:
            if (!ERTS_IS_CRASH_DUMPING)
                erts_magic_ref_save_bin(obj);
            /* fall through... */
	case EXTERNAL_REF_DEF:
	    PRINT_STRING(res, fn, arg, "#Ref<");
	    PRINT_UWORD(res, fn, arg, 'u', 0, 1,
			(ErlPfUWord) ref_channel_no(wobj));
	    ref_num = ref_numbers(wobj);
	    for (i = ref_no_numbers(wobj)-1; i >= 0; i--) {
		PRINT_CHAR(res, fn, arg, '.');
		PRINT_UWORD(res, fn, arg, 'u', 0, 1, (ErlPfUWord) ref_num[i]);
	    }
	    PRINT_CHAR(res, fn, arg, '>');
	    break;
	case PID_DEF:
	case EXTERNAL_PID_DEF:
	    PRINT_CHAR(res, fn, arg, '<');
	    PRINT_UWORD(res, fn, arg, 'u', 0, 1,
			(ErlPfUWord) pid_channel_no(wobj));
	    PRINT_CHAR(res, fn, arg, '.');
	    PRINT_UWORD(res, fn, arg, 'u', 0, 1,
			(ErlPfUWord) pid_number(wobj));
	    PRINT_CHAR(res, fn, arg, '.');
	    PRINT_UWORD(res, fn, arg, 'u', 0, 1,
			(ErlPfUWord) pid_serial(wobj));
	    PRINT_CHAR(res, fn, arg, '>');
	    break;
	case PORT_DEF:
	case EXTERNAL_PORT_DEF:
	    PRINT_STRING(res, fn, arg, "#Port<");
	    PRINT_UWORD(res, fn, arg, 'u', 0, 1,
			(ErlPfUWord) port_channel_no(wobj));
	    PRINT_CHAR(res, fn, arg, '.');
	    PRINT_UWORD(res, fn, arg, 'u', 0, 1,
			(ErlPfUWord) port_number(wobj));
	    PRINT_CHAR(res, fn, arg, '>');
	    break;
	case LIST_DEF:
	    if (is_printable_string(obj)) {
		int c;
		PRINT_CHAR(res, fn, arg, '"');
		nobj = list_val(obj);
		while (1) {
		    if ((*dcount)-- <= 0)
			goto L_done;
		    c = signed_val(*nobj++);
		    if (c == '\n')
			PRINT_STRING(res, fn, arg, "\\n");
		    else {
			if (c == '"')
			    PRINT_CHAR(res, fn, arg, '\\');
			PRINT_CHAR(res, fn, arg, (char) c);
		    }
		    if (is_not_list(*nobj))
			break;
		    nobj = list_val(*nobj);
		}
		PRINT_CHAR(res, fn, arg, '"');
	    } else {
		PRINT_CHAR(res, fn, arg, '[');
		WSTACK_PUSH(s,PRT_CLOSE_LIST);
		goto L_print_one_cons;
	    }
	    break;
	case TUPLE_DEF:
	    nobj = tuple_val(wobj);	/* pointer to arity */
	    i = arityval(*nobj);	/* arity */
	    PRINT_CHAR(res, fn, arg, '{');
	    WSTACK_PUSH(s,PRT_CLOSE_TUPLE);
	    ++nobj;
	    if (i > 0) {
		WSTACK_PUSH2(s, (UWord) nobj, PRT_LAST_ARRAY_ELEMENT+i-1);
	    }
	    break;
	case FLOAT_DEF: {
	    FloatDef ff;
	    GET_DOUBLE(wobj, ff);
	    PRINT_DOUBLE(res, fn, arg, 'e', 6, 0, ff.fd);
	}
	    break;
	case BINARY_DEF:
	    {
		byte* bytep;
		Uint bytesize = binary_size(obj);
		Uint bitoffs;
		Uint bitsize;
		byte octet;
		ERTS_GET_BINARY_BYTES(obj, bytep, bitoffs, bitsize);

		if (bitsize || !bytesize
		    || !is_printable_ascii(bytep, bytesize, bitoffs)) {
		    int is_first = 1;
		    PRINT_STRING(res, fn, arg, "<<");
		    while (bytesize) {
			if (is_first)
			    is_first = 0;
			else
			    PRINT_CHAR(res, fn, arg, ',');
			if (bitoffs)
			    octet = (bytep[0] << bitoffs) | (bytep[1] >> (8-bitoffs));
			else
			    octet = bytep[0];
			PRINT_UWORD(res, fn, arg, 'u', 0, 1, octet);
			++bytep;
			--bytesize;
		    }
		    if (bitsize) {
			Uint bits = bitoffs + bitsize;
			octet = bytep[0];
			if (bits < 8)
			    octet >>= 8 - bits;
			else if (bits > 8) {
			    bits -= 8;  /* bits in last byte */
			    octet <<= bits;
			    octet |= bytep[1] >> (8 - bits);
			}
			octet &= (1 << bitsize) - 1;
			if (is_first)
			    is_first = 0;
			else
			    PRINT_CHAR(res, fn, arg, ',');
			PRINT_UWORD(res, fn, arg, 'u', 0, 1, octet);
			PRINT_CHAR(res, fn, arg, ':');
			PRINT_UWORD(res, fn, arg, 'u', 0, 1, bitsize);
		    }
		    PRINT_STRING(res, fn, arg, ">>");
		}
		else {
		    PRINT_STRING(res, fn, arg, "<<\"");
		    while (bytesize) {
			if (bitoffs)
			    octet = (bytep[0] << bitoffs) | (bytep[1] >> (8-bitoffs));
			else
			    octet = bytep[0];
			if (octet == '"')
			    PRINT_CHAR(res, fn, arg, '\\');
			PRINT_CHAR(res, fn, arg, octet);
			++bytep;
			--bytesize;
		    }
		    PRINT_STRING(res, fn, arg, "\">>");
		}
	    }
	    break;
	case EXPORT_DEF:
	    {
		Export* ep = *((Export **) (export_val(wobj) + 1));
		Atom* module = atom_tab(atom_val(ep->info.mfa.module));
		Atom* name = atom_tab(atom_val(ep->info.mfa.function));

		PRINT_STRING(res, fn, arg, "fun ");
		PRINT_BUF(res, fn, arg, module->name, module->len);
		PRINT_CHAR(res, fn, arg, ':');
		PRINT_BUF(res, fn, arg, name->name, name->len);
		PRINT_CHAR(res, fn, arg, '/');
		PRINT_SWORD(res, fn, arg, 'd', 0, 1,
			    (ErlPfSWord) ep->info.mfa.arity);
	    }
	    break;
	case FUN_DEF:
	    {
		ErlFunThing *funp = (ErlFunThing *) fun_val(wobj);
		Atom *ap = atom_tab(atom_val(funp->fe->module));

		PRINT_STRING(res, fn, arg, "#Fun<");
		PRINT_BUF(res, fn, arg, ap->name, ap->len);
		PRINT_CHAR(res, fn, arg, '.');
		PRINT_SWORD(res, fn, arg, 'd', 0, 1,
			    (ErlPfSWord) funp->fe->old_index);
		PRINT_CHAR(res, fn, arg, '.');
		PRINT_SWORD(res, fn, arg, 'd', 0, 1,
			    (ErlPfSWord) funp->fe->old_uniq);
		PRINT_CHAR(res, fn, arg, '>');
	    }
	    break;
	case MAP_DEF:
            if (is_flatmap(wobj)) {
                Uint n;
                Eterm *ks, *vs;
                flatmap_t *mp = (flatmap_t *)flatmap_val(wobj);
                n  = flatmap_get_size(mp);
                ks = flatmap_get_keys(mp);
                vs = flatmap_get_values(mp);

                PRINT_CHAR(res, fn, arg, '#');
                PRINT_CHAR(res, fn, arg, '{');
                WSTACK_PUSH(s, PRT_CLOSE_TUPLE);
                if (n > 0) {
                    n--;
                    WSTACK_PUSH5(s, vs[n], PRT_TERM, PRT_ASSOC, ks[n], PRT_TERM);
                    while (n--) {
                        WSTACK_PUSH6(s, PRT_COMMA, vs[n], PRT_TERM, PRT_ASSOC,
                                ks[n], PRT_TERM);
                    }
                }
            } else {
                Uint n, mapval;
                Eterm *head;
                head = hashmap_val(wobj);
                mapval = MAP_HEADER_VAL(*head);
                switch (MAP_HEADER_TYPE(*head)) {
                case MAP_HEADER_TAG_HAMT_HEAD_ARRAY:
                case MAP_HEADER_TAG_HAMT_HEAD_BITMAP:
                    PRINT_STRING(res, fn, arg, "#<");
                    PRINT_UWORD(res, fn, arg, 'x', 0, 1, mapval);
                    PRINT_STRING(res, fn, arg, ">{");
                    WSTACK_PUSH(s,PRT_CLOSE_TUPLE);
                    n = hashmap_bitcount(mapval);
                    ASSERT(n < 17);
                    head += 2;
                    if (n > 0) {
                        n--;
                        WSTACK_PUSH(s, head[n]);
                        WSTACK_PUSH(s, PRT_TERM);
                        while (n--) {
                            WSTACK_PUSH(s, PRT_COMMA);
                            WSTACK_PUSH(s, head[n]);
                            WSTACK_PUSH(s, PRT_TERM);
                        }
                    }
                    break;
                case MAP_HEADER_TAG_HAMT_NODE_BITMAP:
                    n = hashmap_bitcount(mapval);
                    head++;
                    PRINT_CHAR(res, fn, arg, '<');
                    PRINT_UWORD(res, fn, arg, 'x', 0, 1, mapval);
                    PRINT_STRING(res, fn, arg, ">{");
                    WSTACK_PUSH(s,PRT_CLOSE_TUPLE);
                    ASSERT(n < 17);
                    if (n > 0) {
                        n--;
                        WSTACK_PUSH(s, head[n]);
                        WSTACK_PUSH(s, PRT_TERM);
                        while (n--) {
                            WSTACK_PUSH(s, PRT_COMMA);
                            WSTACK_PUSH(s, head[n]);
                            WSTACK_PUSH(s, PRT_TERM);
                        }
                    }
                    break;
                }
            }
            break;
	case MATCHSTATE_DEF:
	    PRINT_STRING(res, fn, arg, "#MatchState");
	    break;
        default:
	    PRINT_STRING(res, fn, arg, "<unknown:");
	    PRINT_POINTER(res, fn, arg, wobj);
	    PRINT_CHAR(res, fn, arg, '>');
	    break;
	}
    }

 L_done:
    DESTROY_WSTACK(s);
    return res;
}


int
erts_printf_term(fmtfn_t fn, void* arg, ErlPfEterm term, long precision) {
    int res;
    ERTS_CT_ASSERT(sizeof(ErlPfEterm) == sizeof(Eterm));

    res = print_term(fn, arg, (Eterm)term, &precision);
    if (res < 0)
	return res;
    if (precision <= 0)
	PRINT_STRING(res, fn, arg, "... ");
    return res;
}