#include "stdio_impl.h" #include #include #include #include #include #include #include #include #include /* Some useful macros */ #define MAX(a, b) ((a) > (b) ? (a) : (b)) #define MIN(a, b) ((a) < (b) ? (a) : (b)) /* Convenient bit representation for modifier flags, which all fall * within 31 codepoints of the space character. */ #define ALT_FORM (1U << ('#' - ' ')) #define ZERO_PAD (1U << ('0' - ' ')) #define LEFT_ADJ (1U << ('-' - ' ')) #define PAD_POS (1U << (' ' - ' ')) #define MARK_POS (1U << ('+' - ' ')) #define GROUPED (1U << ('\'' - ' ')) #define FLAGMASK (ALT_FORM | ZERO_PAD | LEFT_ADJ | PAD_POS | MARK_POS | GROUPED) #if UINT_MAX == ULONG_MAX #define LONG_IS_INT #endif #if SIZE_MAX != ULONG_MAX || UINTMAX_MAX != ULLONG_MAX #define ODD_TYPES #endif /* State machine to accept length modifiers + conversion specifiers. * Result is 0 on failure, or an argument type to pop on success. */ enum { BARE, LPRE, LLPRE, HPRE, HHPRE, BIGLPRE, ZTPRE, JPRE, STOP, PTR, INT, UINT, ULLONG, #ifndef LONG_IS_INT LONG, ULONG, #else #define LONG INT #define ULONG UINT #endif SHORT, USHORT, CHAR, UCHAR, #ifdef ODD_TYPES LLONG, SIZET, IMAX, UMAX, PDIFF, UIPTR, #else #define LLONG ULLONG #define SIZET ULONG #define IMAX LLONG #define UMAX ULLONG #define PDIFF LONG #define UIPTR ULONG #endif DBL, LDBL, NOARG, MAXSTATE }; #define S(x) [(x) - 'A'] static const unsigned char states[]['z' - 'A' + 1] = { { /* 0: bare types */ S('d') = INT, S('i') = INT, S('o') = UINT, S('u') = UINT, S('x') = UINT, S('X') = UINT, S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL, S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL, S('c') = CHAR, S('C') = INT, S('s') = PTR, S('S') = PTR, S('p') = UIPTR, S('n') = PTR, S('m') = NOARG, S('l') = LPRE, S('h') = HPRE, S('L') = BIGLPRE, S('z') = ZTPRE, S('j') = JPRE, S('t') = ZTPRE, }, { /* 1: l-prefixed */ S('d') = LONG, S('i') = LONG, S('o') = ULONG, S('u') = ULONG, S('x') = ULONG, S('X') = ULONG, S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL, S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL, S('c') = INT, S('s') = PTR, S('n') = PTR, S('l') = LLPRE, }, { /* 2: ll-prefixed */ S('d') = LLONG, S('i') = LLONG, S('o') = ULLONG, S('u') = ULLONG, S('x') = ULLONG, S('X') = ULLONG, S('n') = PTR, }, { /* 3: h-prefixed */ S('d') = SHORT, S('i') = SHORT, S('o') = USHORT, S('u') = USHORT, S('x') = USHORT, S('X') = USHORT, S('n') = PTR, S('h') = HHPRE, }, { /* 4: hh-prefixed */ S('d') = CHAR, S('i') = CHAR, S('o') = UCHAR, S('u') = UCHAR, S('x') = UCHAR, S('X') = UCHAR, S('n') = PTR, }, { /* 5: L-prefixed */ S('e') = LDBL, S('f') = LDBL, S('g') = LDBL, S('a') = LDBL, S('E') = LDBL, S('F') = LDBL, S('G') = LDBL, S('A') = LDBL, S('n') = PTR, }, { /* 6: z- or t-prefixed (assumed to be same size) */ S('d') = PDIFF, S('i') = PDIFF, S('o') = SIZET, S('u') = SIZET, S('x') = SIZET, S('X') = SIZET, S('n') = PTR, }, { /* 7: j-prefixed */ S('d') = IMAX, S('i') = IMAX, S('o') = UMAX, S('u') = UMAX, S('x') = UMAX, S('X') = UMAX, S('n') = PTR, }}; #define OOB(x) ((unsigned)(x) - 'A' > 'z' - 'A') union arg { uintmax_t i; long double f; void* p; }; __NO_SAFESTACK static void pop_arg(union arg* arg, int type, va_list* ap) { /* Give the compiler a hint for optimizing the switch. */ if ((unsigned)type > MAXSTATE) return; switch (type) { case PTR: arg->p = va_arg(*ap, void*); break; case INT: arg->i = va_arg(*ap, int); break; case UINT: arg->i = va_arg(*ap, unsigned int); #ifndef LONG_IS_INT break; case LONG: arg->i = va_arg(*ap, long); break; case ULONG: arg->i = va_arg(*ap, unsigned long); #endif break; case ULLONG: arg->i = va_arg(*ap, unsigned long long); break; case SHORT: arg->i = (short)va_arg(*ap, int); break; case USHORT: arg->i = (unsigned short)va_arg(*ap, int); break; case CHAR: arg->i = (signed char)va_arg(*ap, int); break; case UCHAR: arg->i = (unsigned char)va_arg(*ap, int); #ifdef ODD_TYPES break; case LLONG: arg->i = va_arg(*ap, long long); break; case SIZET: arg->i = va_arg(*ap, size_t); break; case IMAX: arg->i = va_arg(*ap, intmax_t); break; case UMAX: arg->i = va_arg(*ap, uintmax_t); break; case PDIFF: arg->i = va_arg(*ap, ptrdiff_t); break; case UIPTR: arg->i = (uintptr_t)va_arg(*ap, void*); #endif break; case DBL: arg->f = va_arg(*ap, double); break; case LDBL: arg->f = va_arg(*ap, long double); } } __NO_SAFESTACK static void out(FILE* f, const char* s, size_t l) { if (!(f->flags & F_ERR)) __fwritex((void*)s, l, f); } __NO_SAFESTACK static void pad(FILE* f, char c, int w, int l, int fl) { char pad[256]; if (fl & (LEFT_ADJ | ZERO_PAD) || l >= w) return; l = w - l; memset(pad, c, l > sizeof pad ? sizeof pad : l); for (; l >= sizeof pad; l -= sizeof pad) out(f, pad, sizeof pad); out(f, pad, l); } static const char xdigits[16] = {"0123456789ABCDEF"}; __NO_SAFESTACK static char* fmt_x(uintmax_t x, char* s, int lower) { for (; x; x >>= 4) *--s = xdigits[(x & 15)] | lower; return s; } __NO_SAFESTACK static char* fmt_o(uintmax_t x, char* s) { for (; x; x >>= 3) *--s = '0' + (x & 7); return s; } __NO_SAFESTACK static char* fmt_u(uintmax_t x, char* s) { unsigned long y; for (; x > ULONG_MAX; x /= 10) *--s = '0' + x % 10; for (y = x; y; y /= 10) *--s = '0' + y % 10; return s; } /* Do not override this check. The floating point printing code below * depends on the float.h constants being right. If they are wrong, it * may overflow the stack. */ #if LDBL_MANT_DIG == 53 typedef char compiler_defines_long_double_incorrectly[9 - (int)sizeof(long double)]; #endif static int fmt_fp(FILE* f, long double y, int w, int p, int fl, int t) { uint32_t big[(LDBL_MANT_DIG + 28) / 29 + 1 // mantissa expansion + (LDBL_MAX_EXP + LDBL_MANT_DIG + 28 + 8) / 9]; // exponent expansion uint32_t *a, *d, *r, *z; int e2 = 0, e, i, j, l; char buf[9 + LDBL_MANT_DIG / 4], *s; const char* prefix = "-0X+0X 0X-0x+0x 0x"; int pl; char ebuf0[3 * sizeof(int)], *ebuf = &ebuf0[3 * sizeof(int)], *estr; pl = 1; if (signbit(y)) { y = -y; } else if (fl & MARK_POS) { prefix += 3; } else if (fl & PAD_POS) { prefix += 6; } else prefix++, pl = 0; if (!isfinite(y)) { const char* s = (t & 32) ? "inf" : "INF"; if (y != y) s = (t & 32) ? "nan" : "NAN"; pad(f, ' ', w, 3 + pl, fl & ~ZERO_PAD); out(f, prefix, pl); out(f, s, 3); pad(f, ' ', w, 3 + pl, fl ^ LEFT_ADJ); return MAX(w, 3 + pl); } y = frexpl(y, &e2) * 2; if (y) e2--; if ((t | 32) == 'a') { long double round = 8.0; int re; if (t & 32) prefix += 9; pl += 2; if (p < 0 || p >= LDBL_MANT_DIG / 4 - 1) re = 0; else re = LDBL_MANT_DIG / 4 - 1 - p; if (re) { while (re--) round *= 16; if (*prefix == '-') { y = -y; y -= round; y += round; y = -y; } else { y += round; y -= round; } } estr = fmt_u(e2 < 0 ? -e2 : e2, ebuf); if (estr == ebuf) *--estr = '0'; *--estr = (e2 < 0 ? '-' : '+'); *--estr = t + ('p' - 'a'); s = buf; do { int x = y; *s++ = xdigits[x] | (t & 32); y = 16 * (y - x); if (s - buf == 1 && (y || p > 0 || (fl & ALT_FORM))) *s++ = '.'; } while (y); if (p && s - buf - 2 < p) l = (p + 2) + (ebuf - estr); else l = (s - buf) + (ebuf - estr); pad(f, ' ', w, pl + l, fl); out(f, prefix, pl); pad(f, '0', w, pl + l, fl ^ ZERO_PAD); out(f, buf, s - buf); pad(f, '0', l - (ebuf - estr) - (s - buf), 0, 0); out(f, estr, ebuf - estr); pad(f, ' ', w, pl + l, fl ^ LEFT_ADJ); return MAX(w, pl + l); } if (p < 0) p = 6; if (y) y *= 0x1p28, e2 -= 28; if (e2 < 0) a = r = z = big; else a = r = z = big + sizeof(big) / sizeof(*big) - LDBL_MANT_DIG - 1; do { *z = y; y = 1000000000 * (y - *z++); } while (y); while (e2 > 0) { uint32_t carry = 0; int sh = MIN(29, e2); for (d = z - 1; d >= a; d--) { uint64_t x = ((uint64_t)*d << sh) + carry; *d = x % 1000000000; carry = x / 1000000000; } if (carry) *--a = carry; while (z > a && !z[-1]) z--; e2 -= sh; } while (e2 < 0) { uint32_t carry = 0, *b; int sh = MIN(9, -e2), need = 1 + (p + LDBL_MANT_DIG / 3 + 8) / 9; for (d = a; d < z; d++) { uint32_t rm = *d & ((1 << sh) - 1); *d = (*d >> sh) + carry; carry = (1000000000 >> sh) * rm; } if (!*a) a++; if (carry) *z++ = carry; /* Avoid (slow!) computation past requested precision */ b = (t | 32) == 'f' ? r : a; if (z - b > need) z = b + need; e2 += sh; } if (a < z) for (i = 10, e = 9 * (r - a); *a >= i; i *= 10, e++) ; else e = 0; /* Perform rounding: j is precision after the radix (possibly neg) */ j = p - ((t | 32) != 'f') * e - ((t | 32) == 'g' && p); if (j < 9 * (z - r - 1)) { uint32_t x; /* We avoid C's broken division of negative numbers */ d = r + 1 + ((j + 9 * LDBL_MAX_EXP) / 9 - LDBL_MAX_EXP); j += 9 * LDBL_MAX_EXP; j %= 9; for (i = 10, j++; j < 9; i *= 10, j++) ; x = *d % i; /* Are there any significant digits past j? */ if (x || d + 1 != z) { long double round = 2 / LDBL_EPSILON; long double small; if (*d / i & 1) round += 2; if (x < i / 2) small = 0x0.8p0; else if (x == i / 2 && d + 1 == z) small = 0x1.0p0; else small = 0x1.8p0; if (pl && *prefix == '-') round *= -1, small *= -1; *d -= x; /* Decide whether to round by probing round+small */ if (round + small != round) { *d = *d + i; while (*d > 999999999) { *d-- = 0; if (d < a) *--a = 0; (*d)++; } for (i = 10, e = 9 * (r - a); *a >= i; i *= 10, e++) ; } } if (z > d + 1) z = d + 1; } for (; z > a && !z[-1]; z--) ; if ((t | 32) == 'g') { if (!p) p++; if (p > e && e >= -4) { t--; p -= e + 1; } else { t -= 2; p--; } if (!(fl & ALT_FORM)) { /* Count trailing zeros in last place */ if (z > a && z[-1]) for (i = 10, j = 0; z[-1] % i == 0; i *= 10, j++) ; else j = 9; if ((t | 32) == 'f') p = MIN(p, MAX(0, 9 * (z - r - 1) - j)); else p = MIN(p, MAX(0, 9 * (z - r - 1) + e - j)); } } l = 1 + p + (p || (fl & ALT_FORM)); if ((t | 32) == 'f') { if (e > 0) l += e; } else { estr = fmt_u(e < 0 ? -e : e, ebuf); while (ebuf - estr < 2) *--estr = '0'; *--estr = (e < 0 ? '-' : '+'); *--estr = t; l += ebuf - estr; } pad(f, ' ', w, pl + l, fl); out(f, prefix, pl); pad(f, '0', w, pl + l, fl ^ ZERO_PAD); if ((t | 32) == 'f') { if (a > r) a = r; for (d = a; d <= r; d++) { char* s = fmt_u(*d, buf + 9); if (d != a) while (s > buf) *--s = '0'; else if (s == buf + 9) *--s = '0'; out(f, s, buf + 9 - s); } if (p || (fl & ALT_FORM)) out(f, ".", 1); for (; d < z && p > 0; d++, p -= 9) { char* s = fmt_u(*d, buf + 9); while (s > buf) *--s = '0'; out(f, s, MIN(9, p)); } pad(f, '0', p + 9, 9, 0); } else { if (z <= a) z = a + 1; for (d = a; d < z && p >= 0; d++) { char* s = fmt_u(*d, buf + 9); if (s == buf + 9) *--s = '0'; if (d != a) while (s > buf) *--s = '0'; else { out(f, s++, 1); if (p > 0 || (fl & ALT_FORM)) out(f, ".", 1); } out(f, s, MIN(buf + 9 - s, p)); p -= buf + 9 - s; } pad(f, '0', p + 18, 18, 0); out(f, estr, ebuf - estr); } pad(f, ' ', w, pl + l, fl ^ LEFT_ADJ); return MAX(w, pl + l); } __NO_SAFESTACK static int getint(char** s) { int i; for (i = 0; isdigit(**s); (*s)++) i = 10 * i + (**s - '0'); return i; } __NO_SAFESTACK static int printf_core(FILE* f, const char* fmt, va_list* ap, union arg* nl_arg, int* nl_type) { char *a, *z, *s = (char *)fmt; unsigned l10n = 0, fl; int w, p; union arg arg; int argpos; unsigned st, ps; int cnt = 0, l = 0; int i; char buf[sizeof(uintmax_t) * 3 + 3 + LDBL_MANT_DIG / 4]; const char* prefix; int t, pl; wchar_t wc[2]; wchar_t* ws; char mb[4]; for (;;) { /* Update output count, end loop when fmt is exhausted */ if (cnt >= 0) { if (l > INT_MAX - cnt) { errno = EOVERFLOW; cnt = -1; } else cnt += l; } if (!*s) break; /* Handle literal text and %% format specifiers */ for (a = s; *s && *s != '%'; s++) ; for (z = s; s[0] == '%' && s[1] == '%'; z++, s += 2) ; l = z - a; if (f) out(f, a, l); if (l) continue; if (isdigit(s[1]) && s[2] == '$') { l10n = 1; argpos = s[1] - '0'; s += 3; } else { argpos = -1; s++; } /* Read modifier flags */ for (fl = 0; (unsigned)*s - ' ' < 32 && (FLAGMASK & (1U << (*s - ' '))); s++) fl |= 1U << (*s - ' '); /* Read field width */ if (*s == '*') { if (isdigit(s[1]) && s[2] == '$') { l10n = 1; nl_type[s[1] - '0'] = INT; w = nl_arg[s[1] - '0'].i; s += 3; } else if (!l10n) { w = f ? va_arg(*ap, int) : 0; s++; } else return -1; if (w < 0) fl |= LEFT_ADJ, w = -w; } else if ((w = getint(&s)) < 0) return -1; /* Read precision */ if (*s == '.' && s[1] == '*') { if (isdigit(s[2]) && s[3] == '$') { nl_type[s[2] - '0'] = INT; p = nl_arg[s[2] - '0'].i; s += 4; } else if (!l10n) { p = f ? va_arg(*ap, int) : 0; s += 2; } else return -1; } else if (*s == '.') { s++; p = getint(&s); } else p = -1; /* Format specifier state machine */ st = 0; do { if (OOB(*s)) return -1; ps = st; st = states[st] S(*s++); } while (st - 1 < STOP); if (!st) return -1; /* Check validity of argument type (nl/normal) */ if (st == NOARG) { if (argpos >= 0) return -1; } else { if (argpos >= 0) nl_type[argpos] = st, arg = nl_arg[argpos]; else if (f) pop_arg(&arg, st, ap); else return 0; } if (!f) continue; z = buf + sizeof(buf); prefix = "-+ 0X0x"; pl = 0; t = s[-1]; /* Transform ls,lc -> S,C */ if (ps && (t & 15) == 3) t &= ~32; /* - and 0 flags are mutually exclusive */ if (fl & LEFT_ADJ) fl &= ~ZERO_PAD; switch (t) { case 'n': switch (ps) { case BARE: *(int*)arg.p = cnt; break; case LPRE: *(long*)arg.p = cnt; break; case LLPRE: *(long long*)arg.p = cnt; break; case HPRE: *(unsigned short*)arg.p = cnt; break; case HHPRE: *(unsigned char*)arg.p = cnt; break; case ZTPRE: *(size_t*)arg.p = cnt; break; case JPRE: *(uintmax_t*)arg.p = cnt; break; } continue; case 'p': p = MAX(p, 2 * sizeof(void*)); t = 'x'; fl |= ALT_FORM; case 'x': case 'X': a = fmt_x(arg.i, z, t & 32); if (arg.i && (fl & ALT_FORM)) prefix += (t >> 4), pl = 2; if (0) { case 'o': a = fmt_o(arg.i, z); if ((fl & ALT_FORM) && p < z - a + 1) p = z - a + 1; } if (0) { case 'd': case 'i': pl = 1; if (arg.i > INTMAX_MAX) { arg.i = -arg.i; } else if (fl & MARK_POS) { prefix++; } else if (fl & PAD_POS) { prefix += 2; } else pl = 0; case 'u': a = fmt_u(arg.i, z); } if (p >= 0) fl &= ~ZERO_PAD; if (!arg.i && !p) { a = z; break; } p = MAX(p, z - a + !arg.i); break; case 'c': *(a = z - (p = 1)) = arg.i; fl &= ~ZERO_PAD; break; case 'm': if (1) a = strerror(errno); else case 's': a = arg.p ? arg.p : (char*)"(null)"; z = memchr(a, 0, p); if (!z) z = a + p; else p = z - a; fl &= ~ZERO_PAD; break; case 'C': wc[0] = arg.i; wc[1] = 0; arg.p = wc; p = -1; case 'S': ws = arg.p; for (i = l = 0; i < 0U + p && *ws && (l = wctomb(mb, *ws++)) >= 0 && l <= 0U + p - i; i += l) ; if (l < 0) return -1; p = i; pad(f, ' ', w, p, fl); ws = arg.p; for (i = 0; i < 0U + p && *ws && i + (l = wctomb(mb, *ws++)) <= p; i += l) out(f, mb, l); pad(f, ' ', w, p, fl ^ LEFT_ADJ); l = w > p ? w : p; continue; case 'e': case 'f': case 'g': case 'a': case 'E': case 'F': case 'G': case 'A': l = fmt_fp(f, arg.f, w, p, fl, t); continue; } if (p < z - a) p = z - a; if (w < pl + p) w = pl + p; pad(f, ' ', w, pl + p, fl); out(f, prefix, pl); pad(f, '0', w, pl + p, fl ^ ZERO_PAD); pad(f, '0', p, z - a, 0); out(f, a, z - a); pad(f, ' ', w, pl + p, fl ^ LEFT_ADJ); l = w; } if (f) return cnt; if (!l10n) return 0; for (i = 1; i <= NL_ARGMAX && nl_type[i]; i++) pop_arg(nl_arg + i, nl_type[i], ap); for (; i <= NL_ARGMAX && !nl_type[i]; i++) ; if (i <= NL_ARGMAX) return -1; return 1; } __NO_SAFESTACK int vfprintf(FILE* restrict f, const char* restrict fmt, va_list ap) { va_list ap2; int nl_type[NL_ARGMAX + 1] = {}; union arg nl_arg[NL_ARGMAX + 1]; unsigned char internal_buf[80], *saved_buf = 0; int olderr; int ret; /* the copy allows passing va_list* even if va_list is an array */ va_copy(ap2, ap); if (printf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) { va_end(ap2); return -1; } FLOCK(f); olderr = f->flags & F_ERR; if (f->mode < 1) f->flags &= ~F_ERR; if (!f->buf_size) { saved_buf = f->buf; f->wpos = f->wbase = f->buf = internal_buf; f->buf_size = sizeof internal_buf; f->wend = internal_buf + sizeof internal_buf; } ret = printf_core(f, fmt, &ap2, nl_arg, nl_type); if (saved_buf) { f->write(f, 0, 0); if (!f->wpos) ret = -1; f->buf = saved_buf; f->buf_size = 0; f->wpos = f->wbase = f->wend = 0; } if (f->flags & F_ERR) ret = -1; f->flags |= olderr; FUNLOCK(f); va_end(ap2); return ret; }