platform_bionic/libc/stdio/vfprintf.cpp
Elliott Hughes 2109f12c3b Add strerrordesc_np() and strerrorname_np().
strerrordesc_np() isn't very useful (being just another name for
strerror()), but strerrorname_np() lets you get "ENOSYS" for ENOSYS,
which will make some of our test assertion messages clearer when we
switch over from strerror().

This also adds `%#m` formatting to all the relevant functions.

Test: treehugger
Change-Id: Icfe07a39a307d591c3f4f2a09d008dc021643062
2023-09-27 11:21:12 -07:00

736 lines
22 KiB
C++

/* $OpenBSD: vfprintf.c,v 1.71 2016/01/04 15:47:47 schwarze Exp $ */
/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#define CHAR_TYPE char
#define FUNCTION_NAME __vfprintf
#define CHAR_TYPE_STRLEN strlen
#define CHAR_TYPE_STRNLEN strnlen
#define CHAR_TYPE_INF "INF"
#define CHAR_TYPE_inf "inf"
#define CHAR_TYPE_NAN "NAN"
#define CHAR_TYPE_nan "nan"
#define CHAR_TYPE_ORIENTATION ORIENT_BYTES
#define PRINT(ptr, len) \
do { \
iovp->iov_base = (ptr); \
iovp->iov_len = (len); \
uio.uio_resid += (len); \
iovp++; \
if (++uio.uio_iovcnt >= NIOV) { \
if (helpers::sprint(fp, &uio)) goto error; \
iovp = iov; \
} \
} while (0)
#define FLUSH() \
do { \
if (uio.uio_resid && helpers::sprint(fp, &uio)) goto error; \
uio.uio_iovcnt = 0; \
iovp = iov; \
} while (0)
#include "printf_common.h"
int FUNCTION_NAME(FILE* fp, const CHAR_TYPE* fmt0, va_list ap) {
int caller_errno = errno;
int n, n2;
CHAR_TYPE* cp; /* handy char pointer (short term usage) */
CHAR_TYPE sign; /* sign prefix (' ', '+', '-', or \0) */
int flags; /* flags as above */
int ret; /* return value accumulator */
int width; /* width from format (%8d), or 0 */
int prec; /* precision from format; <0 for N/A */
/*
* We can decompose the printed representation of floating
* point numbers into several parts, some of which may be empty:
*
* [+|-| ] [0x|0X] MMM . NNN [e|E|p|P] [+|-] ZZ
* A B ---C--- D E F
*
* A: 'sign' holds this value if present; '\0' otherwise
* B: ox[1] holds the 'x' or 'X'; '\0' if not hexadecimal
* C: cp points to the string MMMNNN. Leading and trailing
* zeros are not in the string and must be added.
* D: expchar holds this character; '\0' if no exponent, e.g. %f
* F: at least two digits for decimal, at least one digit for hex
*/
char* decimal_point = nullptr;
int signflag; /* true if float is negative */
union { /* floating point arguments %[aAeEfFgG] */
double dbl;
long double ldbl;
} fparg;
int expt; /* integer value of exponent */
char expchar; /* exponent character: [eEpP\0] */
char* dtoaend; /* pointer to end of converted digits */
int expsize; /* character count for expstr */
int lead; /* sig figs before decimal or group sep */
int ndig; /* actual number of digits returned by dtoa */
CHAR_TYPE expstr[MAXEXPDIG + 2]; /* buffer for exponent string: e+ZZZ */
char* dtoaresult = nullptr;
uintmax_t _umax; /* integer arguments %[diouxX] */
enum { BIN, OCT, DEC, HEX } base; /* base for %[bBdiouxX] conversion */
int dprec; /* a copy of prec if %[bBdiouxX], 0 otherwise */
int realsz; /* field size expanded by dprec */
int size; /* size of converted field or string */
const char* xdigs; /* digits for %[xX] conversion */
#define NIOV 8
struct __suio uio; /* output information: summary */
struct __siov iov[NIOV]; /* ... and individual io vectors */
struct __siov* iovp; /* for PRINT macro */
CHAR_TYPE buf[BUF]; /* buffer with space for digits of uintmax_t */
CHAR_TYPE ox[2]; /* space for 0x; ox[1] is either x, X, or \0 */
union arg* argtable; /* args, built due to positional arg */
union arg statargtable[STATIC_ARG_TBL_SIZE];
size_t argtablesiz;
int nextarg; /* 1-based argument index */
va_list orgap; /* original argument pointer */
CHAR_TYPE* convbuf; /* buffer for wide/multibyte conversion */
/*
* Choose PADSIZE to trade efficiency vs. size. If larger printf
* fields occur frequently, increase PADSIZE and make the initialisers
* below longer.
*/
#define PADSIZE 16 /* pad chunk size */
static CHAR_TYPE blanks[PADSIZE] = {
' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' '
};
static CHAR_TYPE zeroes[PADSIZE] = {
'0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0'
};
static const char xdigs_lower[] = "0123456789abcdef";
static const char xdigs_upper[] = "0123456789ABCDEF";
_SET_ORIENTATION(fp, CHAR_TYPE_ORIENTATION);
// Writing "" to a read only file returns EOF, not 0.
if (cantwrite(fp)) {
errno = EBADF;
return EOF;
}
// Optimize writes to stderr and other unbuffered files).
if ((fp->_flags & (__SNBF | __SWR | __SRW)) == (__SNBF | __SWR) && fp->_file >= 0) {
return (__sbprintf(fp, fmt0, ap));
}
CHAR_TYPE* fmt = const_cast<CHAR_TYPE*>(fmt0);
argtable = nullptr;
nextarg = 1;
va_copy(orgap, ap);
uio.uio_iov = iovp = iov;
uio.uio_resid = 0;
uio.uio_iovcnt = 0;
ret = 0;
convbuf = nullptr;
/*
* Scan the format for conversions (`%' character).
*/
for (;;) {
int ch;
for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++) continue;
if (fmt != cp) {
ptrdiff_t m = fmt - cp;
if (m < 0 || m > INT_MAX - ret) goto overflow;
PRINT(cp, m);
ret += m;
}
if (ch == '\0') goto done;
fmt++; /* skip over '%' */
flags = 0;
dprec = 0;
width = 0;
prec = -1;
sign = '\0';
ox[1] = '\0';
rflag:
ch = *fmt++;
reswitch:
switch (ch) {
case ' ':
/*
* ``If the space and + flags both appear, the space
* flag will be ignored.''
* -- ANSI X3J11
*/
if (!sign) sign = ' ';
goto rflag;
case '#':
flags |= ALT;
goto rflag;
case '\'':
/* grouping not implemented */
goto rflag;
case '*':
/*
* ``A negative field width argument is taken as a
* - flag followed by a positive field width.''
* -- ANSI X3J11
* They don't exclude field widths read from args.
*/
GETASTER(width);
if (width >= 0) goto rflag;
if (width == INT_MIN) goto overflow;
width = -width;
__BIONIC_FALLTHROUGH;
case '-':
flags |= LADJUST;
goto rflag;
case '+':
sign = '+';
goto rflag;
case '.':
if ((ch = *fmt++) == '*') {
GETASTER(n);
prec = n < 0 ? -1 : n;
goto rflag;
}
n = 0;
while (is_digit(ch)) {
APPEND_DIGIT(n, ch);
ch = *fmt++;
}
if (ch == '$') {
nextarg = n;
if (argtable == nullptr) {
argtable = statargtable;
if (__find_arguments(fmt0, orgap, &argtable, &argtablesiz) == -1) {
ret = -1;
goto error;
}
}
goto rflag;
}
prec = n;
goto reswitch;
case '0':
/*
* ``Note that 0 is taken as a flag, not as the
* beginning of a field width.''
* -- ANSI X3J11
*/
flags |= ZEROPAD;
goto rflag;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
n = 0;
do {
APPEND_DIGIT(n, ch);
ch = *fmt++;
} while (is_digit(ch));
if (ch == '$') {
nextarg = n;
if (argtable == nullptr) {
argtable = statargtable;
if (__find_arguments(fmt0, orgap, &argtable, &argtablesiz) == -1) {
ret = -1;
goto error;
}
}
goto rflag;
}
width = n;
goto reswitch;
case 'L':
flags |= LONGDBL;
goto rflag;
case 'h':
if (*fmt == 'h') {
fmt++;
flags |= CHARINT;
} else {
flags |= SHORTINT;
}
goto rflag;
case 'j':
flags |= MAXINT;
goto rflag;
case 'l':
if (*fmt == 'l') {
fmt++;
flags |= LLONGINT;
} else {
flags |= LONGINT;
}
goto rflag;
case 'q':
flags |= LLONGINT;
goto rflag;
case 't':
flags |= PTRINT;
goto rflag;
case 'z':
flags |= SIZEINT;
goto rflag;
case 'B':
case 'b':
_umax = UARG();
base = BIN;
if (flags & ALT && _umax != 0) ox[1] = ch;
goto nosign;
case 'C':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
case 'c':
if (flags & LONGINT) {
mbstate_t mbs;
size_t mbseqlen;
memset(&mbs, 0, sizeof(mbs));
mbseqlen = wcrtomb(buf, (wchar_t)GETARG(wint_t), &mbs);
if (mbseqlen == (size_t)-1) {
ret = -1;
goto error;
}
cp = buf;
size = (int)mbseqlen;
} else {
*(cp = buf) = GETARG(int);
size = 1;
}
sign = '\0';
break;
case 'D':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
case 'd':
case 'i':
_umax = SARG();
signed_decimal:
if ((intmax_t)_umax < 0) {
_umax = -_umax;
sign = '-';
}
base = DEC;
goto number;
case 'a':
case 'A':
if (ch == 'a') {
ox[1] = 'x';
xdigs = xdigs_lower;
expchar = 'p';
} else {
ox[1] = 'X';
xdigs = xdigs_upper;
expchar = 'P';
}
if (prec >= 0) prec++;
if (dtoaresult) __freedtoa(dtoaresult);
if (flags & LONGDBL) {
fparg.ldbl = GETARG(long double);
dtoaresult = __hldtoa(fparg.ldbl, xdigs, prec, &expt, &signflag, &dtoaend);
if (dtoaresult == nullptr) {
errno = ENOMEM;
goto error;
}
} else {
fparg.dbl = GETARG(double);
dtoaresult = __hdtoa(fparg.dbl, xdigs, prec, &expt, &signflag, &dtoaend);
if (dtoaresult == nullptr) {
errno = ENOMEM;
goto error;
}
}
if (prec < 0) prec = dtoaend - dtoaresult;
if (expt == INT_MAX) ox[1] = '\0';
goto fp_common;
case 'e':
case 'E':
expchar = ch;
if (prec < 0) /* account for digit before decpt */
prec = DEFPREC + 1;
else
prec++;
goto fp_begin;
case 'f':
case 'F':
expchar = '\0';
goto fp_begin;
case 'g':
case 'G':
expchar = ch - ('g' - 'e');
if (prec == 0) prec = 1;
fp_begin:
if (prec < 0) prec = DEFPREC;
if (dtoaresult) __freedtoa(dtoaresult);
if (flags & LONGDBL) {
fparg.ldbl = GETARG(long double);
dtoaresult = __ldtoa(&fparg.ldbl, expchar ? 2 : 3, prec, &expt, &signflag, &dtoaend);
if (dtoaresult == nullptr) {
errno = ENOMEM;
goto error;
}
} else {
fparg.dbl = GETARG(double);
dtoaresult = __dtoa(fparg.dbl, expchar ? 2 : 3, prec, &expt, &signflag, &dtoaend);
if (dtoaresult == nullptr) {
errno = ENOMEM;
goto error;
}
if (expt == 9999) expt = INT_MAX;
}
fp_common:
#if CHAR_TYPE_ORIENTATION == ORIENT_BYTES
cp = dtoaresult;
#else
free(convbuf);
cp = convbuf = helpers::mbsconv(dtoaresult, -1);
if (cp == nullptr) goto error;
#endif
if (signflag) sign = '-';
if (expt == INT_MAX) { /* inf or nan */
if (*cp == 'N') {
cp = const_cast<CHAR_TYPE*>((ch >= 'a') ? CHAR_TYPE_nan : CHAR_TYPE_NAN);
} else {
cp = const_cast<CHAR_TYPE*>((ch >= 'a') ? CHAR_TYPE_inf : CHAR_TYPE_INF);
}
size = 3;
flags &= ~ZEROPAD;
break;
}
flags |= FPT;
ndig = dtoaend - dtoaresult;
if (ch == 'g' || ch == 'G') {
if (expt > -4 && expt <= prec) {
/* Make %[gG] smell like %[fF] */
expchar = '\0';
if (flags & ALT)
prec -= expt;
else
prec = ndig - expt;
if (prec < 0) prec = 0;
} else {
/*
* Make %[gG] smell like %[eE], but
* trim trailing zeroes if no # flag.
*/
if (!(flags & ALT)) prec = ndig;
}
}
if (expchar) {
expsize = exponent(expstr, expt - 1, expchar);
size = expsize + prec;
if (prec > 1 || flags & ALT) ++size;
} else {
/* space for digits before decimal point */
if (expt > 0)
size = expt;
else /* "0" */
size = 1;
/* space for decimal pt and following digits */
if (prec || flags & ALT) size += prec + 1;
lead = expt;
}
break;
case 'n':
__fortify_fatal("%%n not allowed on Android");
case 'm':
if (flags & ALT) {
cp = const_cast<char*>(strerrorname_np(caller_errno));
if (cp == nullptr) {
_umax = caller_errno;
goto signed_decimal;
}
} else {
cp = strerror_r(caller_errno, buf, sizeof(buf));
}
goto string;
case 'O':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
case 'o':
_umax = UARG();
base = OCT;
goto nosign;
case 'p':
/*
* ``The argument shall be a pointer to void. The
* value of the pointer is converted to a sequence
* of printable characters, in an implementation-
* defined manner.''
* -- ANSI X3J11
*/
_umax = (u_long)GETARG(void*);
base = HEX;
xdigs = xdigs_lower;
ox[1] = 'x';
goto nosign;
case 'S':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
case 's':
if (flags & LONGINT) {
wchar_t* wcp;
free(convbuf);
convbuf = nullptr;
if ((wcp = GETARG(wchar_t*)) == nullptr) {
cp = const_cast<char*>("(null)");
} else {
convbuf = helpers::wcsconv(wcp, prec);
if (convbuf == nullptr) {
ret = -1;
goto error;
}
cp = convbuf;
}
} else if ((cp = GETARG(char*)) == nullptr) {
cp = const_cast<char*>("(null)");
}
string:
if (prec >= 0) {
size = CHAR_TYPE_STRNLEN(cp, prec);
} else {
size_t len;
if ((len = CHAR_TYPE_STRLEN(cp)) > INT_MAX) goto overflow;
size = (int)len;
}
sign = '\0';
break;
case 'U':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
case 'u':
_umax = UARG();
base = DEC;
goto nosign;
case 'w': {
n = 0;
bool fast = false;
ch = *fmt++;
if (ch == 'f') {
fast = true;
ch = *fmt++;
}
while (is_digit(ch)) {
APPEND_DIGIT(n, ch);
ch = *fmt++;
}
flags |= helpers::w_to_flag(n, fast);
goto reswitch;
}
case 'X':
xdigs = xdigs_upper;
goto hex;
case 'x':
xdigs = xdigs_lower;
hex:
_umax = UARG();
base = HEX;
/* leading 0x/X only if non-zero */
if (flags & ALT && _umax != 0) ox[1] = ch;
/* unsigned conversions */
nosign:
sign = '\0';
/*
* ``... diouXx conversions ... if a precision is
* specified, the 0 flag will be ignored.''
* -- ANSI X3J11
*/
number:
if ((dprec = prec) >= 0) flags &= ~ZEROPAD;
/*
* ``The result of converting a zero value with an
* explicit precision of zero is no characters.''
* -- ANSI X3J11
*/
cp = buf + BUF;
if (_umax != 0 || prec != 0) {
/*
* Unsigned mod is hard, and unsigned mod
* by a constant is easier than that by
* a variable; hence this switch.
*/
switch (base) {
case BIN:
do {
*--cp = to_char(_umax & 1);
_umax >>= 1;
} while (_umax);
break;
case OCT:
do {
*--cp = to_char(_umax & 7);
_umax >>= 3;
} while (_umax);
/* handle octal leading 0 */
if (flags & ALT && *cp != '0') *--cp = '0';
break;
case DEC:
/* many numbers are 1 digit */
while (_umax >= 10) {
*--cp = to_char(_umax % 10);
_umax /= 10;
}
*--cp = to_char(_umax);
break;
case HEX:
do {
*--cp = xdigs[_umax & 15];
_umax >>= 4;
} while (_umax);
break;
default:
abort();
}
}
size = buf + BUF - cp;
if (size > BUF) abort(); /* should never happen */
break;
default: /* "%?" prints ?, unless ? is NUL */
if (ch == '\0') goto done;
/* pretend it was %c with argument ch */
cp = buf;
*cp = ch;
size = 1;
sign = '\0';
break;
}
/*
* All reasonable formats wind up here. At this point, `cp'
* points to a string which (if not flags&LADJUST) should be
* padded out to `width' places. If flags&ZEROPAD, it should
* first be prefixed by any sign or other prefix; otherwise,
* it should be blank padded before the prefix is emitted.
* After any left-hand padding and prefixing, emit zeroes
* required by a decimal %[bBdiouxX] precision, then print the
* string proper, then emit zeroes required by any leftover
* floating precision; finally, if LADJUST, pad with blanks.
*
* Compute actual size, so we know how much to pad.
* size excludes decimal prec; realsz includes it.
*/
realsz = dprec > size ? dprec : size;
if (sign) realsz++;
if (ox[1]) realsz += 2;
/* right-adjusting blank padding */
if ((flags & (LADJUST | ZEROPAD)) == 0) PAD(width - realsz, blanks);
/* prefix */
if (sign) PRINT(&sign, 1);
if (ox[1]) { /* ox[1] is either x, X, or \0 */
ox[0] = '0';
PRINT(ox, 2);
}
/* right-adjusting zero padding */
if ((flags & (LADJUST | ZEROPAD)) == ZEROPAD) PAD(width - realsz, zeroes);
/* leading zeroes from decimal precision */
PAD(dprec - size, zeroes);
/* the string or number proper */
if ((flags & FPT) == 0) {
PRINT(cp, size);
} else { /* glue together f_p fragments */
if (decimal_point == nullptr) decimal_point = nl_langinfo(RADIXCHAR);
if (!expchar) { /* %[fF] or sufficiently short %[gG] */
CHAR_TYPE* end = cp + ndig;
if (expt <= 0) {
PRINT(zeroes, 1);
if (prec || flags & ALT) PRINT(decimal_point, 1);
PAD(-expt, zeroes);
/* already handled initial 0's */
prec += expt;
} else {
PRINTANDPAD(cp, end, lead, zeroes);
cp += lead;
if (prec || flags & ALT) PRINT(decimal_point, 1);
}
PRINTANDPAD(cp, end, prec, zeroes);
} else { /* %[eE] or sufficiently long %[gG] */
if (prec > 1 || flags & ALT) {
buf[0] = *cp++;
buf[1] = *decimal_point;
PRINT(buf, 2);
PRINT(cp, ndig - 1);
PAD(prec - ndig, zeroes);
} else { /* XeYYY */
PRINT(cp, 1);
}
PRINT(expstr, expsize);
}
}
/* left-adjusting padding (always blank) */
if (flags & LADJUST) PAD(width - realsz, blanks);
/* finally, adjust ret */
if (width < realsz) width = realsz;
if (width > INT_MAX - ret) goto overflow;
ret += width;
FLUSH(); /* copy out the I/O vectors */
}
done:
FLUSH();
error:
va_end(orgap);
if (__sferror(fp)) ret = -1;
goto finish;
overflow:
errno = ENOMEM;
ret = -1;
finish:
free(convbuf);
if (dtoaresult) __freedtoa(dtoaresult);
if (argtable != nullptr && argtable != statargtable) {
munmap(argtable, argtablesiz);
argtable = nullptr;
}
return (ret);
}