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#include "stdio_impl.h"
#include <errno.h>
#include <ctype.h>
#include <limits.h>
#include <string.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdlib.h>
#include <wchar.h>
#include <inttypes.h>
#include <math.h>
#include <float.h>
/* 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)
/* 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,
LONG, ULONG,
SHORT, USHORT, CHAR, UCHAR,
LLONG, SIZET, IMAX, UMAX, PDIFF, UIPTR,
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;
};
static void pop_arg(union arg *arg, int type, va_list *ap)
{
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);
break; case LONG: arg->i = va_arg(*ap, long);
break; case ULONG: arg->i = va_arg(*ap, unsigned long);
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);
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 *);
break; case DBL: arg->f = va_arg(*ap, double);
break; case LDBL: arg->f = va_arg(*ap, long double);
}
}
static void out(FILE *f, const char *s, size_t l)
{
if (!(f->flags & F_ERR)) __fwritex((void *)s, l, f);
}
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"
};
static char *fmt_x(uintmax_t x, char *s, int lower)
{
for (; x; x>>=4) *--s = xdigits[(x&15)]|lower;
return s;
}
static char *fmt_o(uintmax_t x, char *s)
{
for (; x; x>>=3) *--s = '0' + (x&7);
return s;
}
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)) {
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) {
round *= 1<<(LDBL_MANT_DIG%4);
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 > INT_MAX-2-(ebuf-estr)-pl)
return -1;
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/3U+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) || (i==1000000000 && d>a && (d[-1]&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));
}
}
if (p > INT_MAX-1-(p || (fl&ALT_FORM)))
return -1;
l = 1 + p + (p || (fl&ALT_FORM));
if ((t|32)=='f') {
if (e > INT_MAX-l) return -1;
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;
if (ebuf-estr > INT_MAX-l) return -1;
l += ebuf-estr;
}
if (l > INT_MAX-pl) return -1;
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);
}
static int getint(char **s) {
int i;
for (i=0; isdigit(**s); (*s)++) {
if (i > INT_MAX/10U || **s-'0' > INT_MAX-10*i) i = -1;
else i = 10*i + (**s-'0');
}
return i;
}
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, xp;
union arg arg;
int argpos;
unsigned st, ps;
int cnt=0, l=0;
size_t i;
char buf[sizeof(uintmax_t)*3+3+LDBL_MANT_DIG/4];
const char *prefix;
int t, pl;
wchar_t wc[2], *ws;
char mb[4];
for (;;) {
/* This error is only specified for snprintf, but since it's
* unspecified for other forms, do the same. Stop immediately
* on overflow; otherwise %n could produce wrong results. */
if (l > INT_MAX - cnt) goto overflow;
/* Update output count, end loop when fmt is exhausted */
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);
if (z-a > INT_MAX-cnt) goto overflow;
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 goto inval;
if (w<0) fl|=LEFT_ADJ, w=-w;
} else if ((w=getint(&s))<0) goto overflow;
/* 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 goto inval;
xp = (p>=0);
} else if (*s=='.') {
s++;
p = getint(&s);
xp = 1;
} else {
p = -1;
xp = 0;
}
/* Format specifier state machine */
st=0;
do {
if (OOB(*s)) goto inval;
ps=st;
st=states[st]S(*s++);
} while (st-1<STOP);
if (!st) goto inval;
/* Check validity of argument type (nl/normal) */
if (st==NOARG) {
if (argpos>=0) goto inval;
} 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 (xp && p<0) goto overflow;
if (xp) 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 : "(null)";
z = a + strnlen(a, p<0 ? INT_MAX : p);
if (p<0 && *z) goto overflow;
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<p && *ws && (l=wctomb(mb, *ws++))>=0 && l<=p-i; i+=l);
if (l<0) return -1;
if (i > INT_MAX) goto overflow;
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':
if (xp && p<0) goto overflow;
l = fmt_fp(f, arg.f, w, p, fl, t);
if (l<0) goto overflow;
continue;
}
if (p < z-a) p = z-a;
if (p > INT_MAX-pl) goto overflow;
if (w < pl+p) w = pl+p;
if (w > INT_MAX-cnt) goto overflow;
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) goto inval;
return 1;
inval:
errno = EINVAL;
return -1;
overflow:
errno = EOVERFLOW;
return -1;
}
int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap)
{
va_list ap2;
int nl_type[NL_ARGMAX+1] = {0};
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->buf = internal_buf;
f->buf_size = sizeof internal_buf;
f->wpos = f->wbase = f->wend = 0;
}
if (!f->wend && __towrite(f)) ret = -1;
else 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;
}
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