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Diffstat (limited to 'lib/printf/printfcommon.h')
| -rw-r--r-- | lib/printf/printfcommon.h | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/lib/printf/printfcommon.h b/lib/printf/printfcommon.h new file mode 100644 index 0000000..f777be8 --- /dev/null +++ b/lib/printf/printfcommon.h @@ -0,0 +1,256 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Chris Torek. + * + * Copyright (c) 2011 The FreeBSD Foundation + * + * Portions of this software were developed by David Chisnall + * under sponsorship from the FreeBSD Foundation. + * + * 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. + */ + +/* + * This file defines common routines used by both printf and wprintf. + * You must define CHAR to either char or wchar_t prior to including this. + */ + + +static CHAR *__ujtoa(uintmax_t, CHAR *, int, int, const char *); +static CHAR *__ultoa(u_long, CHAR *, int, int, const char *); + +#define NIOV 8 +struct io_state { + struct fbuf *cb; + size_t avail; +}; + +static inline void +io_init(struct io_state *iop, struct fbuf *cb) +{ + iop->cb = cb; + iop->avail = cb ? cb->len - (cb->pos - cb->buf) : 0; +} + +/* + * WARNING: The buffer passed to io_print() is not copied immediately; it must + * remain valid until io_flush() is called. + */ +static inline int +io_print(struct io_state *iop, const CHAR * __restrict ptr, size_t len) +{ + size_t copylen = len; + + if (!iop->cb || !len) + return 0; + if (iop->avail < copylen) + copylen = iop->avail; + + memcpy(iop->cb->pos, ptr, copylen); + iop->avail -= copylen; + iop->cb->pos += copylen; + return 0; +} + +/* + * 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 const CHAR blanks[PADSIZE] = +{' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '}; +static const CHAR zeroes[PADSIZE] = +{'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'}; + +/* + * Pad with blanks or zeroes. 'with' should point to either the blanks array + * or the zeroes array. + */ +static inline int +io_pad(struct io_state *iop, int howmany, const CHAR * __restrict with) +{ + int n; + + while (howmany > 0) { + n = (howmany >= PADSIZE) ? PADSIZE : howmany; + if (io_print(iop, with, n)) + return (-1); + howmany -= n; + } + return (0); +} + +/* + * Print exactly len characters of the string spanning p to ep, truncating + * or padding with 'with' as necessary. + */ +static inline int +io_printandpad(struct io_state *iop, const CHAR *p, const CHAR *ep, + int len, const CHAR * __restrict with) +{ + int p_len; + + p_len = ep - p; + if (p_len > len) + p_len = len; + if (p_len > 0) { + if (io_print(iop, p, p_len)) + return (-1); + } else { + p_len = 0; + } + return (io_pad(iop, len - p_len, with)); +} + +/* + * Convert an unsigned long to ASCII for printf purposes, returning + * a pointer to the first character of the string representation. + * Octal numbers can be forced to have a leading zero; hex numbers + * use the given digits. + */ +static CHAR * +__ultoa(u_long val, CHAR *endp, int base, int octzero, const char *xdigs) +{ + CHAR *cp = endp; + long sval; + + /* + * Handle the three cases separately, in the hope of getting + * better/faster code. + */ + switch (base) { + case 10: + if (val < 10) { /* many numbers are 1 digit */ + *--cp = to_char(val); + return (cp); + } + /* + * On many machines, unsigned arithmetic is harder than + * signed arithmetic, so we do at most one unsigned mod and + * divide; this is sufficient to reduce the range of + * the incoming value to where signed arithmetic works. + */ + if (val > LONG_MAX) { + *--cp = to_char(val % 10); + sval = val / 10; + } else + sval = val; + do { + *--cp = to_char(sval % 10); + sval /= 10; + } while (sval != 0); + break; + + case 2: + do { + *--cp = to_char(val & 1); + val >>= 1; + } while (val); + break; + + case 8: + do { + *--cp = to_char(val & 7); + val >>= 3; + } while (val); + if (octzero && *cp != '0') + *--cp = '0'; + break; + + case 16: + do { + *--cp = xdigs[val & 15]; + val >>= 4; + } while (val); + break; + + default: /* oops */ + abort(); + } + return (cp); +} + +/* Identical to __ultoa, but for intmax_t. */ +static CHAR * +__ujtoa(uintmax_t val, CHAR *endp, int base, int octzero, const char *xdigs) +{ + CHAR *cp = endp; + intmax_t sval; + + /* quick test for small values; __ultoa is typically much faster */ + /* (perhaps instead we should run until small, then call __ultoa?) */ + if (val <= ULONG_MAX) + return (__ultoa((u_long)val, endp, base, octzero, xdigs)); + switch (base) { + case 10: + if (val < 10) { + *--cp = to_char(val % 10); + return (cp); + } + if (val > INTMAX_MAX) { + *--cp = to_char(val % 10); + sval = val / 10; + } else + sval = val; + do { + *--cp = to_char(sval % 10); + sval /= 10; + } while (sval != 0); + break; + + case 2: + do { + *--cp = to_char(val & 1); + val >>= 1; + } while (val); + break; + + case 8: + do { + *--cp = to_char(val & 7); + val >>= 3; + } while (val); + if (octzero && *cp != '0') + *--cp = '0'; + break; + + case 16: + do { + *--cp = xdigs[val & 15]; + val >>= 4; + } while (val); + break; + + default: + abort(); + } + return (cp); +} |