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- #include <dragonstub/dragonstub.h>
- #include <dragonstub/linux/stdarg.h>
- #include <dragonstub/bug.h>
- #include <dragonstub/minmax.h>
- #include <dragonstub/limits.h>
- #include <dragonstub/compiler_types.h>
- #include <dragonstub/linux/err.h>
- #include <dragonstub/linux/byteorder.h>
- #include <dragonstub/linux/div64.h>
- struct printf_spec {
- unsigned int type : 8;
- signed int field_width : 24;
- unsigned int flags : 8;
- unsigned int base : 8;
- signed int precision : 16;
- } __packed;
- #define SIGN 1
- #define LEFT 2
- #define PLUS 4
- #define SPACE 8
- #define ZEROPAD 16
- #define SMALL 32
- #define SPECIAL 64
- static_assert(SIGN == 1);
- static_assert(ZEROPAD == ('0' - ' '));
- static_assert(SMALL == ('a' ^ 'A'));
- enum format_type {
- FORMAT_TYPE_NONE,
- FORMAT_TYPE_WIDTH,
- FORMAT_TYPE_PRECISION,
- FORMAT_TYPE_CHAR,
- FORMAT_TYPE_STR,
- FORMAT_TYPE_PTR,
- FORMAT_TYPE_PERCENT_CHAR,
- FORMAT_TYPE_INVALID,
- FORMAT_TYPE_LONG_LONG,
- FORMAT_TYPE_ULONG,
- FORMAT_TYPE_LONG,
- FORMAT_TYPE_UBYTE,
- FORMAT_TYPE_BYTE,
- FORMAT_TYPE_USHORT,
- FORMAT_TYPE_SHORT,
- FORMAT_TYPE_UINT,
- FORMAT_TYPE_INT,
- FORMAT_TYPE_SIZE_T,
- FORMAT_TYPE_PTRDIFF
- };
- static noinline_for_stack int skip_atoi(const char **s)
- {
- int i = 0;
- do {
- i = i * 10 + *((*s)++) - '0';
- } while (isdigit(**s));
- return i;
- }
- static const u16 decpair[100] = {
- #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
- _(0), _(1), _(2), _(3), _(4), _(5), _(6), _(7), _(8), _(9),
- _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
- _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
- _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
- _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
- _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
- _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
- _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
- _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
- _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
- #undef _
- };
- static noinline_for_stack char *put_dec_trunc8(char *buf, unsigned r)
- {
- unsigned q;
-
- if (r < 100)
- goto out_r;
-
- q = (r * (u64)0x28f5c29) >> 32;
- *((u16 *)buf) = decpair[r - 100 * q];
- buf += 2;
-
- if (q < 100)
- goto out_q;
-
- r = (q * (u64)0x28f5c29) >> 32;
- *((u16 *)buf) = decpair[q - 100 * r];
- buf += 2;
-
- if (r < 100)
- goto out_r;
-
- q = (r * 0x147b) >> 19;
- *((u16 *)buf) = decpair[r - 100 * q];
- buf += 2;
- out_q:
-
- r = q;
- out_r:
-
- *((u16 *)buf) = decpair[r];
- buf += r < 10 ? 1 : 2;
- return buf;
- }
- #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
- static noinline_for_stack char *put_dec_full8(char *buf, unsigned r)
- {
- unsigned q;
-
- q = (r * (u64)0x28f5c29) >> 32;
- *((u16 *)buf) = decpair[r - 100 * q];
- buf += 2;
-
- r = (q * (u64)0x28f5c29) >> 32;
- *((u16 *)buf) = decpair[q - 100 * r];
- buf += 2;
-
- q = (r * 0x147b) >> 19;
- *((u16 *)buf) = decpair[r - 100 * q];
- buf += 2;
-
- *((u16 *)buf) = decpair[q];
- buf += 2;
- return buf;
- }
- static noinline_for_stack char *put_dec(char *buf, unsigned long long n)
- {
- if (n >= 100 * 1000 * 1000)
- buf = put_dec_full8(buf, do_div(n, 100 * 1000 * 1000));
-
- if (n >= 100 * 1000 * 1000)
- buf = put_dec_full8(buf, do_div(n, 100 * 1000 * 1000));
-
- return put_dec_trunc8(buf, n);
- }
- #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
- static void put_dec_full4(char *buf, unsigned r)
- {
- unsigned q;
-
- q = (r * 0x147b) >> 19;
- *((u16 *)buf) = decpair[r - 100 * q];
- buf += 2;
-
- *((u16 *)buf) = decpair[q];
- }
- static noinline_for_stack unsigned put_dec_helper4(char *buf, unsigned x)
- {
- uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
- put_dec_full4(buf, x - q * 10000);
- return q;
- }
- static char *put_dec(char *buf, unsigned long long n)
- {
- uint32_t d3, d2, d1, q, h;
- if (n < 100 * 1000 * 1000)
- return put_dec_trunc8(buf, n);
- d1 = ((uint32_t)n >> 16);
- h = (n >> 32);
- d2 = (h)&0xffff;
- d3 = (h >> 16);
-
- q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
- q = put_dec_helper4(buf, q);
- q += 7671 * d3 + 9496 * d2 + 6 * d1;
- q = put_dec_helper4(buf + 4, q);
- q += 4749 * d3 + 42 * d2;
- q = put_dec_helper4(buf + 8, q);
- q += 281 * d3;
- buf += 12;
- if (q)
- buf = put_dec_trunc8(buf, q);
- else
- while (buf[-1] == '0')
- --buf;
- return buf;
- }
- #endif
- #define FIELD_WIDTH_MAX ((1 << 23) - 1)
- #define PRECISION_MAX ((1 << 15) - 1)
- static void set_field_width(struct printf_spec *spec, int width)
- {
- spec->field_width = width;
- if (WARN_ONCE(spec->field_width != width, "field width %d too large",
- width)) {
- spec->field_width =
- clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
- }
- }
- static void set_precision(struct printf_spec *spec, int prec)
- {
- spec->precision = prec;
- if (WARN_ONCE(spec->precision != prec, "precision %d too large",
- prec)) {
- spec->precision = clamp(prec, 0, PRECISION_MAX);
- }
- }
- static noinline_for_stack char *
- number(char *buf, char *end, unsigned long long num, struct printf_spec spec)
- {
-
- char tmp[3 * sizeof(num)] __aligned(2);
- char sign;
- char locase;
- int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
- int i;
- bool is_zero = num == 0LL;
- int field_width = spec.field_width;
- int precision = spec.precision;
-
- locase = (spec.flags & SMALL);
- if (spec.flags & LEFT)
- spec.flags &= ~ZEROPAD;
- sign = 0;
- if (spec.flags & SIGN) {
- if ((signed long long)num < 0) {
- sign = '-';
- num = -(signed long long)num;
- field_width--;
- } else if (spec.flags & PLUS) {
- sign = '+';
- field_width--;
- } else if (spec.flags & SPACE) {
- sign = ' ';
- field_width--;
- }
- }
- if (need_pfx) {
- if (spec.base == 16)
- field_width -= 2;
- else if (!is_zero)
- field_width--;
- }
-
- i = 0;
- if (num < spec.base)
- tmp[i++] = hex_asc_upper[num] | locase;
- else if (spec.base != 10) {
- int mask = spec.base - 1;
- int shift = 3;
- if (spec.base == 16)
- shift = 4;
- do {
- tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] |
- locase);
- num >>= shift;
- } while (num);
- } else {
- i = put_dec(tmp, num) - tmp;
- }
-
- if (i > precision)
- precision = i;
-
- field_width -= precision;
- if (!(spec.flags & (ZEROPAD | LEFT))) {
- while (--field_width >= 0) {
- if (buf < end)
- *buf = ' ';
- ++buf;
- }
- }
-
- if (sign) {
- if (buf < end)
- *buf = sign;
- ++buf;
- }
-
- if (need_pfx) {
- if (spec.base == 16 || !is_zero) {
- if (buf < end)
- *buf = '0';
- ++buf;
- }
- if (spec.base == 16) {
- if (buf < end)
- *buf = ('X' | locase);
- ++buf;
- }
- }
-
- if (!(spec.flags & LEFT)) {
- char c = ' ' + (spec.flags & ZEROPAD);
- while (--field_width >= 0) {
- if (buf < end)
- *buf = c;
- ++buf;
- }
- }
-
- while (i <= --precision) {
- if (buf < end)
- *buf = '0';
- ++buf;
- }
-
- while (--i >= 0) {
- if (buf < end)
- *buf = tmp[i];
- ++buf;
- }
-
- while (--field_width >= 0) {
- if (buf < end)
- *buf = ' ';
- ++buf;
- }
- return buf;
- }
- static noinline_for_stack char *
- special_hex_number(char *buf, char *end, unsigned long long num, int size)
- {
- struct printf_spec spec;
- spec.type = FORMAT_TYPE_PTR;
- spec.field_width = 2 + 2 * size;
- spec.flags = SPECIAL | SMALL | ZEROPAD;
- spec.base = 16;
- spec.precision = -1;
- return number(buf, end, num, spec);
- }
- static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
- {
- size_t size;
- if (buf >= end)
- return;
- size = end - buf;
- if (size <= spaces) {
- memset(buf, ' ', size);
- return;
- }
- if (len) {
- if (len > size - spaces)
- len = size - spaces;
- memmove(buf + spaces, buf, len);
- }
- memset(buf, ' ', spaces);
- }
- static noinline_for_stack char *widen_string(char *buf, int n, char *end,
- struct printf_spec spec)
- {
- unsigned spaces;
- if (likely(n >= spec.field_width))
- return buf;
-
- spaces = spec.field_width - n;
- if (!(spec.flags & LEFT)) {
- move_right(buf - n, end, n, spaces);
- return buf + spaces;
- }
- while (spaces--) {
- if (buf < end)
- *buf = ' ';
- ++buf;
- }
- return buf;
- }
- static char *string_nocheck(char *buf, char *end, const char *s,
- struct printf_spec spec)
- {
- int len = 0;
- int lim = spec.precision;
- while (lim--) {
- char c = *s++;
- if (!c)
- break;
- if (buf < end)
- *buf = c;
- ++buf;
- ++len;
- }
- return widen_string(buf, len, end, spec);
- }
- static char *error_string(char *buf, char *end, const char *s,
- struct printf_spec spec)
- {
-
- if (spec.precision == -1)
- spec.precision = 2 * sizeof(void *);
- return string_nocheck(buf, end, s, spec);
- }
- static const char *check_pointer_msg(const void *ptr)
- {
- if (!ptr)
- return "(null)";
- if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
- return "(efault)";
- return NULL;
- }
- static int check_pointer(char **buf, char *end, const void *ptr,
- struct printf_spec spec)
- {
- const char *err_msg;
- err_msg = check_pointer_msg(ptr);
- if (err_msg) {
- *buf = error_string(*buf, end, err_msg, spec);
- return -EFAULT;
- }
- return 0;
- }
- static noinline_for_stack char *string(char *buf, char *end, const char *s,
- struct printf_spec spec)
- {
- if (check_pointer(&buf, end, s, spec))
- return buf;
- return string_nocheck(buf, end, s, spec);
- }
- static char *pointer_string(char *buf, char *end, const void *ptr,
- struct printf_spec spec)
- {
- spec.base = 16;
- spec.flags |= SMALL;
- if (spec.field_width == -1) {
- spec.field_width = 2 * sizeof(ptr);
- spec.flags |= ZEROPAD;
- }
- return number(buf, end, (unsigned long int)ptr, spec);
- }
- static noinline_for_stack char *hex_string(char *buf, char *end, u8 *addr,
- struct printf_spec spec,
- const char *fmt)
- {
- int i, len = 1;
- char separator;
- if (spec.field_width == 0)
-
- return buf;
- if (check_pointer(&buf, end, addr, spec))
- return buf;
- switch (fmt[1]) {
- case 'C':
- separator = ':';
- break;
- case 'D':
- separator = '-';
- break;
- case 'N':
- separator = 0;
- break;
- default:
- separator = ' ';
- break;
- }
- if (spec.field_width > 0)
- len = min_t(int, spec.field_width, 64);
- for (i = 0; i < len; ++i) {
- if (buf < end)
- *buf = hex_asc_hi(addr[i]);
- ++buf;
- if (buf < end)
- *buf = hex_asc_lo(addr[i]);
- ++buf;
- if (separator && i != len - 1) {
- if (buf < end)
- *buf = separator;
- ++buf;
- }
- }
- return buf;
- }
- static noinline_for_stack char *mac_address_string(char *buf, char *end,
- u8 *addr,
- struct printf_spec spec,
- const char *fmt)
- {
- char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
- char *p = mac_addr;
- int i;
- char separator;
- bool reversed = false;
- if (check_pointer(&buf, end, addr, spec))
- return buf;
- switch (fmt[1]) {
- case 'F':
- separator = '-';
- break;
- case 'R':
- reversed = true;
- fallthrough;
- default:
- separator = ':';
- break;
- }
- for (i = 0; i < 6; i++) {
- if (reversed)
- p = hex_byte_pack(p, addr[5 - i]);
- else
- p = hex_byte_pack(p, addr[i]);
- if (fmt[0] == 'M' && i != 5)
- *p++ = separator;
- }
- *p = '\0';
- return string_nocheck(buf, end, mac_addr, spec);
- }
- static char *default_pointer(char *buf, char *end, const void *ptr,
- struct printf_spec spec)
- {
- return pointer_string(buf, end, ptr, spec);
- }
- static char *err_ptr(char *buf, char *end, void *ptr, struct printf_spec spec)
- {
- int err = PTR_ERR(ptr);
-
-
-
-
- spec.flags |= SIGN;
- spec.base = 10;
- return number(buf, end, err, spec);
- }
- static noinline_for_stack char *pointer(const char *fmt, char *buf, char *end,
- void *ptr, struct printf_spec spec)
- {
- switch (*fmt) {
-
-
-
-
-
-
-
-
-
- case 'h':
- return hex_string(buf, end, ptr, spec, fmt);
-
-
-
-
-
-
-
- case 'M':
- case 'm':
-
-
- return mac_address_string(buf, end, ptr, spec, fmt);
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- #ifdef CONFIG_BLOCK
- case 'g':
- return bdev_name(buf, end, ptr, spec, fmt);
- #endif
-
-
-
-
-
-
-
-
-
-
-
-
- case 'x':
- return pointer_string(buf, end, ptr, spec);
- case 'e':
-
- if (!IS_ERR(ptr))
- return default_pointer(buf, end, ptr, spec);
- return err_ptr(buf, end, ptr, spec);
- case 'u':
- case 'k':
- switch (fmt[1]) {
- case 's':
- return string(buf, end, ptr, spec);
- default:
- return error_string(buf, end, "(einval)", spec);
- }
- default:
- return default_pointer(buf, end, ptr, spec);
- }
- }
- static noinline_for_stack int format_decode(const char *fmt,
- struct printf_spec *spec)
- {
- const char *start = fmt;
- char qualifier;
-
- if (spec->type == FORMAT_TYPE_WIDTH) {
- if (spec->field_width < 0) {
- spec->field_width = -spec->field_width;
- spec->flags |= LEFT;
- }
- spec->type = FORMAT_TYPE_NONE;
- goto precision;
- }
-
- if (spec->type == FORMAT_TYPE_PRECISION) {
- if (spec->precision < 0)
- spec->precision = 0;
- spec->type = FORMAT_TYPE_NONE;
- goto qualifier;
- }
-
- spec->type = FORMAT_TYPE_NONE;
- for (; *fmt; ++fmt) {
- if (*fmt == '%')
- break;
- }
-
- if (fmt != start || !*fmt)
- return fmt - start;
-
- spec->flags = 0;
- while (1) {
- bool found = true;
- ++fmt;
- switch (*fmt) {
- case '-':
- spec->flags |= LEFT;
- break;
- case '+':
- spec->flags |= PLUS;
- break;
- case ' ':
- spec->flags |= SPACE;
- break;
- case '#':
- spec->flags |= SPECIAL;
- break;
- case '0':
- spec->flags |= ZEROPAD;
- break;
- default:
- found = false;
- }
- if (!found)
- break;
- }
-
- spec->field_width = -1;
- if (isdigit(*fmt))
- spec->field_width = skip_atoi(&fmt);
- else if (*fmt == '*') {
-
- spec->type = FORMAT_TYPE_WIDTH;
- return ++fmt - start;
- }
- precision:
-
- spec->precision = -1;
- if (*fmt == '.') {
- ++fmt;
- if (isdigit(*fmt)) {
- spec->precision = skip_atoi(&fmt);
- if (spec->precision < 0)
- spec->precision = 0;
- } else if (*fmt == '*') {
-
- spec->type = FORMAT_TYPE_PRECISION;
- return ++fmt - start;
- }
- }
- qualifier:
-
- qualifier = 0;
- if (*fmt == 'h' || _tolower(*fmt) == 'l' || *fmt == 'z' ||
- *fmt == 't') {
- qualifier = *fmt++;
- if (unlikely(qualifier == *fmt)) {
- if (qualifier == 'l') {
- qualifier = 'L';
- ++fmt;
- } else if (qualifier == 'h') {
- qualifier = 'H';
- ++fmt;
- }
- }
- }
-
- spec->base = 10;
- switch (*fmt) {
- case 'c':
- spec->type = FORMAT_TYPE_CHAR;
- return ++fmt - start;
- case 's':
- spec->type = FORMAT_TYPE_STR;
- return ++fmt - start;
- case 'p':
- spec->type = FORMAT_TYPE_PTR;
- return ++fmt - start;
- case '%':
- spec->type = FORMAT_TYPE_PERCENT_CHAR;
- return ++fmt - start;
-
- case 'o':
- spec->base = 8;
- break;
- case 'x':
- spec->flags |= SMALL;
- fallthrough;
- case 'X':
- spec->base = 16;
- break;
- case 'd':
- case 'i':
- spec->flags |= SIGN;
- break;
- case 'u':
- break;
- case 'n':
-
- fallthrough;
- default:
- WARN_ONCE(1,
- "Please remove unsupported %%%c in format string\n",
- *fmt);
- spec->type = FORMAT_TYPE_INVALID;
- return fmt - start;
- }
- if (qualifier == 'L')
- spec->type = FORMAT_TYPE_LONG_LONG;
- else if (qualifier == 'l') {
- BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
- spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
- } else if (qualifier == 'z') {
- spec->type = FORMAT_TYPE_SIZE_T;
- } else if (qualifier == 't') {
- spec->type = FORMAT_TYPE_PTRDIFF;
- } else if (qualifier == 'H') {
- BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
- spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
- } else if (qualifier == 'h') {
- BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
- spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
- } else {
- BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
- spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
- }
- return ++fmt - start;
- }
- int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
- {
- unsigned long long num;
- char *str, *end;
- struct printf_spec spec = { 0 };
-
- if (WARN_ON_ONCE(size > INT_MAX))
- return 0;
- str = buf;
- end = buf + size;
-
- if (end < buf) {
- end = ((void *)-1);
- size = end - buf;
- }
- while (*fmt) {
- const char *old_fmt = fmt;
- int read = format_decode(fmt, &spec);
- fmt += read;
- switch (spec.type) {
- case FORMAT_TYPE_NONE: {
- int copy = read;
- if (str < end) {
- if (copy > end - str)
- copy = end - str;
- memcpy(str, old_fmt, copy);
- }
- str += read;
- break;
- }
- case FORMAT_TYPE_WIDTH:
- set_field_width(&spec, va_arg(args, int));
- break;
- case FORMAT_TYPE_PRECISION:
- set_precision(&spec, va_arg(args, int));
- break;
- case FORMAT_TYPE_CHAR: {
- char c;
- if (!(spec.flags & LEFT)) {
- while (--spec.field_width > 0) {
- if (str < end)
- *str = ' ';
- ++str;
- }
- }
- c = (unsigned char)va_arg(args, int);
- if (str < end)
- *str = c;
- ++str;
- while (--spec.field_width > 0) {
- if (str < end)
- *str = ' ';
- ++str;
- }
- break;
- }
- case FORMAT_TYPE_STR:
- str = string(str, end, va_arg(args, char *), spec);
- break;
- case FORMAT_TYPE_PTR:
- str = pointer(fmt, str, end, va_arg(args, void *),
- spec);
- while (isalnum(*fmt))
- fmt++;
- break;
- case FORMAT_TYPE_PERCENT_CHAR:
- if (str < end)
- *str = '%';
- ++str;
- break;
- case FORMAT_TYPE_INVALID:
-
- goto out;
- default:
- switch (spec.type) {
- case FORMAT_TYPE_LONG_LONG:
- num = va_arg(args, long long);
- break;
- case FORMAT_TYPE_ULONG:
- num = va_arg(args, unsigned long);
- break;
- case FORMAT_TYPE_LONG:
- num = va_arg(args, long);
- break;
- case FORMAT_TYPE_SIZE_T:
- if (spec.flags & SIGN)
- num = va_arg(args, ssize_t);
- else
- num = va_arg(args, size_t);
- break;
- case FORMAT_TYPE_PTRDIFF:
- num = va_arg(args, ptrdiff_t);
- break;
- case FORMAT_TYPE_UBYTE:
- num = (unsigned char)va_arg(args, int);
- break;
- case FORMAT_TYPE_BYTE:
- num = (signed char)va_arg(args, int);
- break;
- case FORMAT_TYPE_USHORT:
- num = (unsigned short)va_arg(args, int);
- break;
- case FORMAT_TYPE_SHORT:
- num = (short)va_arg(args, int);
- break;
- case FORMAT_TYPE_INT:
- num = (int)va_arg(args, int);
- break;
- default:
- num = va_arg(args, unsigned int);
- }
- str = number(str, end, num, spec);
- }
- }
- out:
- if (size > 0) {
- if (str < end)
- *str = '\0';
- else
- end[-1] = '\0';
- }
-
- return str - buf;
- }
- int snprintf(char *buf, size_t size, const char *fmt, ...)
- {
- va_list args;
- int i;
- va_start(args, fmt);
- i = vsnprintf(buf, size, fmt, args);
- va_end(args);
- return i;
- }
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