1505 lines
54 KiB
C
1505 lines
54 KiB
C
/**
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* @author (c) Eyal Rozenberg <eyalroz1@gmx.com>
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* 2021-2022, Haifa, Palestine/Israel
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* @author (c) Marco Paland (info@paland.com)
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* 2014-2019, PALANDesign Hannover, Germany
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*
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* @note Others have made smaller contributions to this file: see the
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* contributors page at https://github.com/eyalroz/printf/graphs/contributors
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* or ask one of the authors. The original code for exponential specifiers was
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* contributed by Martijn Jasperse <m.jasperse@gmail.com>.
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*
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* @brief Small stand-alone implementation of the printf family of functions
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* (`(v)printf`, `(v)s(n)printf` etc., geared towards use on embedded systems with
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* a very limited resources.
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*
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* @note the implementations are thread-safe; re-entrant; use no functions from
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* the standard library; and do not dynamically allocate any memory.
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*
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* @license The MIT License (MIT)
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include <errno.h>
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#include <stdbool.h>
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#include <stdint.h>
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#include <limits.h>
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#include "vlibc_stdio.h"
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#define _VLIBC_IO_HAVE_WRITE ((unsigned char)(0x04))
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#define _VLIBC_IO_HAVE_READ ((unsigned char)(0x08))
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#define _VLIBC_IO_VBUF_MASK ((unsigned char)(0x60))
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#define _VLIBC_IO_VBUF_FBF ((unsigned char)(0x40))
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#define _VLIBC_IO_VBUF_LBF ((unsigned char)(0x20))
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#define _VLIBC_IO_VBUF_NBF ((unsigned char)(0x00))
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#define _VLIBC_IO_AUTO_BUFF ((unsigned char)(0x80))
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#define _VLIBC_TYPEIS_IO ((int)(0x01))
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#define _VLIBC_TYPEIS_FILE ((int)(0x02))
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#ifdef CONFIG_VLIBC_DEBUG
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#define CHECK_FILE(_stream, __ret) \
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do { \
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if ((void *)(_stream) == NULL) { \
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errno = EINVAL; \
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return __ret; \
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} \
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} while (0)
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#else
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#define CHECK_FILE(_stream, __ret) \
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do { \
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} while (0)
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#endif
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#define vlibc_file(_stream) ((vlibc_file_t *)(_stream))
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#define IF_IO_DEV(_stream) \
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if (((vlibc_file(_stream)->magic) & _VLIBC_MAGIC_MASK) == _VLIBC_IO_MAGIC_CODE)
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#define IF_FILE(_stream) \
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if (((vlibc_file(_stream)->magic) & _VLIBC_MAGIC_MASK) == _VLIBC_FILE_MAGIC_CODE)
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#ifdef CONFIG_VLIBC_FATFS
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extern int FRESULT_to_errno[20];
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#endif
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/** @addtogroup config ********************************************************
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* @{
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*/
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// 'ntoa' conversion buffer size, this must be big enough to hold one converted
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// numeric number including padded zeros (dynamically created on stack)
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#ifndef PRINTF_INTEGER_BUFFER_SIZE
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#define PRINTF_INTEGER_BUFFER_SIZE 32
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#endif
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// size of the fixed (on-stack) buffer for printing individual decimal numbers.
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// this must be big enough to hold one converted floating-point value including
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// padded zeros.
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#ifndef PRINTF_DECIMAL_BUFFER_SIZE
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#define PRINTF_DECIMAL_BUFFER_SIZE 32
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#endif
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// Support for the decimal notation floating point conversion specifiers (%f, %F)
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#ifndef CONFIG_VLIBC_FLOAT
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#define CONFIG_VLIBC_FLOAT 1
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#endif
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// Support for the exponential notation floating point conversion specifiers (%e, %g, %E, %G)
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#ifndef CONFIG_VLIBC_FLOAT_EX
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#define CONFIG_VLIBC_FLOAT_EX 0
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#endif
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// Support for the length write-back specifier (%n)
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#ifndef CONFIG_VLIBC_WRITEBACK
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#define CONFIG_VLIBC_WRITEBACK 0
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#endif
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// Default precision for the floating point conversion specifiers (the C standard sets this at 6)
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#ifndef VLIBC_DEFAULT_FLOAT_PRECISION
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#define VLIBC_DEFAULT_FLOAT_PRECISION 6
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#endif
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// According to the C languages standard, printf() and related functions must be able to print any
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// integral number in floating-point notation, regardless of length, when using the %f specifier -
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// possibly hundreds of characters, potentially overflowing your buffers. In this implementation,
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// all values beyond this threshold are switched to exponential notation.
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#ifndef VLIBC_MAX_INTEGRAL_DIGITS_FOR_DECIMAL
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#define VLIBC_MAX_INTEGRAL_DIGITS_FOR_DECIMAL 9
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#endif
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// Support for the long long integral types (with the ll, z and t length modifiers for specifiers
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// %d,%i,%o,%x,%X,%u, and with the %p specifier). Note: 'L' (long double) is not supported.
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#ifndef CONFIG_VLIBC_LONG_LONG
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#define CONFIG_VLIBC_LONG_LONG 0
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#endif
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// The number of terms in a Taylor series expansion of log_10(x) to
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// use for approximation - including the power-zero term (i.e. the
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// value at the point of expansion).
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#ifndef PRINTF_LOG10_TAYLOR_TERMS
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#define PRINTF_LOG10_TAYLOR_TERMS 4
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#endif
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#if PRINTF_LOG10_TAYLOR_TERMS <= 1
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#error "At least one non-constant Taylor expansion is necessary for the log10() calculation"
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#endif
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#define PRINTF_PREFER_DECIMAL false
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#define PRINTF_PREFER_EXPONENTIAL true
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/******************************************************************************
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* @}
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*/
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// The following will convert the number-of-digits into an exponential-notation literal
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#define PRINTF_CONCATENATE(s1, s2) s1##s2
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#define PRINTF_EXPAND_THEN_CONCATENATE(s1, s2) PRINTF_CONCATENATE(s1, s2)
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#define PRINTF_FLOAT_NOTATION_THRESHOLD PRINTF_EXPAND_THEN_CONCATENATE(1e, VLIBC_MAX_INTEGRAL_DIGITS_FOR_DECIMAL)
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// internal flag definitions
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#define FLAGS_ZEROPAD (1U << 0U)
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#define FLAGS_LEFT (1U << 1U)
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#define FLAGS_PLUS (1U << 2U)
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#define FLAGS_SPACE (1U << 3U)
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#define FLAGS_HASH (1U << 4U)
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#define FLAGS_UPPERCASE (1U << 5U)
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#define FLAGS_CHAR (1U << 6U)
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#define FLAGS_SHORT (1U << 7U)
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#define FLAGS_INT (1U << 8U)
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#define FLAGS_LONG (1U << 9U)
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#define FLAGS_LONG_LONG (1U << 10U)
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#define FLAGS_PRECISION (1U << 11U)
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#define FLAGS_ADAPT_EXP (1U << 12U)
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#define FLAGS_POINTER (1U << 13U)
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// Note: Similar, but not identical, effect as FLAGS_HASH
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#define FLAGS_SIGNED (1U << 14U)
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typedef unsigned int printf_flags_t;
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#define BASE_BINARY 2
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#define BASE_OCTAL 8
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#define BASE_DECIMAL 10
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#define BASE_HEX 16
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typedef uint8_t numeric_base_t;
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#if CONFIG_VLIBC_LONG_LONG
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typedef unsigned long long printf_unsigned_value_t;
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typedef long long printf_signed_value_t;
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#else
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typedef unsigned long printf_unsigned_value_t;
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typedef long printf_signed_value_t;
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#endif
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#define PRINTF_MAX_POSSIBLE_BUFFER_SIZE INT_MAX
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// If we were to nitpick, this would actually be INT_MAX + 1,
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// since INT_MAX is the maximum return value, which excludes the
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// trailing '\0'.
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#if (CONFIG_VLIBC_FLOAT || CONFIG_VLIBC_FLOAT_EX)
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#include <float.h>
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#if FLT_RADIX != 2
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#error "Non-binary-radix floating-point types are unsupported."
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#endif
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#if DBL_MANT_DIG == 24
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#define DOUBLE_SIZE_IN_BITS 32
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typedef uint32_t double_uint_t;
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#define DOUBLE_EXPONENT_MASK 0xFFU
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#define DOUBLE_BASE_EXPONENT 127
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#define DOUBLE_MAX_SUBNORMAL_EXPONENT_OF_10 -38
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#define DOUBLE_MAX_SUBNORMAL_POWER_OF_10 1e-38
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#elif DBL_MANT_DIG == 53
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#define DOUBLE_SIZE_IN_BITS 64
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typedef uint64_t double_uint_t;
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#define DOUBLE_EXPONENT_MASK 0x7FFU
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#define DOUBLE_BASE_EXPONENT 1023
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#define DOUBLE_MAX_SUBNORMAL_EXPONENT_OF_10 -308
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#define DOUBLE_MAX_SUBNORMAL_POWER_OF_10 1e-308
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#else
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#error "Unsupported double type configuration"
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#endif
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#define DOUBLE_STORED_MANTISSA_BITS (DBL_MANT_DIG - 1)
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typedef union {
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double_uint_t U;
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double F;
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} double_with_bit_access;
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// This is unnecessary in C99, since compound initializers can be used,
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// but:
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// 1. Some compilers are finicky about this;
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// 2. Some people may want to convert this to C89;
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// 3. If you try to use it as C++, only C++20 supports compound literals
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static inline double_with_bit_access get_bit_access(double x)
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{
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double_with_bit_access dwba;
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dwba.F = x;
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return dwba;
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|
}
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static inline int get_sign_bit(double x)
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{
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// The sign is stored in the highest bit
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return (int)(get_bit_access(x).U >> (DOUBLE_SIZE_IN_BITS - 1));
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}
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static inline int get_exp2(double_with_bit_access x)
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{
|
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// The exponent in an IEEE-754 floating-point number occupies a contiguous
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// sequence of bits (e.g. 52..62 for 64-bit doubles), but with a non-trivial representation: An
|
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// unsigned offset from some negative value (with the extremal offset values reserved for
|
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// special use).
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return (int)((x.U >> DOUBLE_STORED_MANTISSA_BITS) & DOUBLE_EXPONENT_MASK) - DOUBLE_BASE_EXPONENT;
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}
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#define PRINTF_ABS(_x) ((_x) > 0 ? (_x) : -(_x))
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#endif // (CONFIG_VLIBC_FLOAT || CONFIG_VLIBC_FLOAT_EX)
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|
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// Note in particular the behavior here on LONG_MIN or LLONG_MIN; it is valid
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// and well-defined, but if you're not careful you can easily trigger undefined
|
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// behavior with -LONG_MIN or -LLONG_MIN
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#define ABS_FOR_PRINTING(_x) ((printf_unsigned_value_t)((_x) > 0 ? (_x) : -((printf_signed_value_t)_x)))
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|
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// wrapper (used as buffer) for output function type
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//
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// One of the following must hold:
|
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// 1. max is 0
|
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// 2. buffer is non-null
|
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// 3. stream is non-null
|
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//
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// ... otherwise bad things will happen.
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typedef struct {
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VLIBC_FILE *stream;
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char *buffer;
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size_t pos;
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size_t max;
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} output_gadget_t;
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/** @addtogroup putc functions
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* @{
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*/
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static inline void putc_via_buffer(output_gadget_t *output, char c)
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{
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size_t write_pos = output->pos++;
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if (write_pos >= output->max) {
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return;
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}
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output->buffer[write_pos] = c;
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}
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static inline void putc_via_file(output_gadget_t *output, char c)
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{
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size_t write_pos = output->max++;
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output->pos++;
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if (write_pos >= VLIBC_FBUFSIZ) {
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output->max = 0;
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write_pos = 0;
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#ifdef CONFIG_VLIBC_FATFS
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FRESULT fresult;
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size_t bytes;
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fresult = f_write(output->stream->file, output->buffer, VLIBC_FBUFSIZ, &bytes);
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if (fresult != FR_OK) {
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if (fresult <= FR_INVALID_PARAMETER) {
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errno = FRESULT_to_errno[fresult];
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}
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}
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#else
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#endif
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}
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output->buffer[write_pos] = c;
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return;
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}
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static inline void putc_via_iodev_nbf(output_gadget_t *output, char c)
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{
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output->pos++;
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if (__vlibc_io_mem2dev(output->stream->io, &c, 1) == 0) {
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errno = EINVAL;
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}
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}
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static inline void putc_via_iodev_lbf(output_gadget_t *output, char c)
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{
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register char *bg = output->stream->io->bg;
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register char *wp = output->stream->io->wp;
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register char *ed = output->stream->io->ed;
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output->pos++;
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*wp++ = c;
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if ((c == '\n') || (wp == ed)) {
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if (__vlibc_io_mem2dev(output->stream->io, bg, wp - bg) == 0) {
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errno = EINVAL;
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goto done;
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}
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wp = bg;
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}
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done:
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output->stream->io->wp = wp;
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}
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static inline void putc_via_iodev_fbf(output_gadget_t *output, char c)
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{
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register char *bg = output->stream->io->bg;
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register char *wp = output->stream->io->wp;
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register char *ed = output->stream->io->ed;
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output->pos++;
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*wp++ = c;
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if (wp == ed) {
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if (__vlibc_io_mem2dev(output->stream->io, bg, ed - bg) == 0) {
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errno = EINVAL;
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goto done;
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}
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wp = bg;
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}
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done:
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output->stream->io->wp = wp;
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}
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|
|
/**
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* @}
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|
*/
|
|
|
|
/** @addtogroup internal std c functions
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* @{
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|
*/
|
|
|
|
// internal secure strlen
|
|
// @return The length of the string (excluding the terminating 0) limited by 'maxsize'
|
|
// @note strlen uses size_t, but wes only use this function with size_t
|
|
// variables - hence the signature.
|
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static inline size_t strnlen_s_(const char *str, size_t maxsize)
|
|
{
|
|
const char *s;
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for (s = str; *s && maxsize--; ++s)
|
|
;
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return (size_t)(s - str);
|
|
}
|
|
|
|
// internal test if char is a digit (0-9)
|
|
// @return true if char is a digit
|
|
static inline bool is_digit_(char ch)
|
|
{
|
|
return (ch >= '0') && (ch <= '9');
|
|
}
|
|
|
|
// internal ASCII string to size_t conversion
|
|
static size_t atou_(const char **str)
|
|
{
|
|
size_t i = 0U;
|
|
while (is_digit_(**str)) {
|
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i = i * 10U + (size_t)(*((*str)++) - '0');
|
|
}
|
|
return i;
|
|
}
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
// output the specified string in reverse, taking care of any zero-padding
|
|
static void out_rev_(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), const char *buf, size_t len, size_t width, printf_flags_t flags)
|
|
{
|
|
const size_t start_pos = output->pos;
|
|
|
|
// pad spaces up to given width
|
|
if (!(flags & FLAGS_LEFT) && !(flags & FLAGS_ZEROPAD)) {
|
|
for (size_t i = len; i < width; i++) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
|
|
// reverse string
|
|
while (len) {
|
|
putc_function(output, buf[--len]);
|
|
}
|
|
|
|
// append pad spaces up to given width
|
|
if (flags & FLAGS_LEFT) {
|
|
while (output->pos - start_pos < width) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
}
|
|
|
|
// Invoked by print_integer after the actual number has been printed, performing necessary
|
|
// work on the number's prefix (as the number is initially printed in reverse order)
|
|
static void print_integer_finalization(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), char *buf, size_t len, bool negative, numeric_base_t base, size_t precision, size_t width, printf_flags_t flags)
|
|
{
|
|
size_t unpadded_len = len;
|
|
|
|
// pad with leading zeros
|
|
{
|
|
if (!(flags & FLAGS_LEFT)) {
|
|
if (width && (flags & FLAGS_ZEROPAD) && (negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) {
|
|
width--;
|
|
}
|
|
while ((flags & FLAGS_ZEROPAD) && (len < width) && (len < PRINTF_INTEGER_BUFFER_SIZE)) {
|
|
buf[len++] = '0';
|
|
}
|
|
}
|
|
|
|
while ((len < precision) && (len < PRINTF_INTEGER_BUFFER_SIZE)) {
|
|
buf[len++] = '0';
|
|
}
|
|
|
|
if (base == BASE_OCTAL && (len > unpadded_len)) {
|
|
// Since we've written some zeros, we've satisfied the alternative format leading space requirement
|
|
flags &= ~FLAGS_HASH;
|
|
}
|
|
}
|
|
|
|
// handle hash
|
|
if (flags & (FLAGS_HASH | FLAGS_POINTER)) {
|
|
if (!(flags & FLAGS_PRECISION) && len && ((len == precision) || (len == width))) {
|
|
// Let's take back some padding digits to fit in what will eventually
|
|
// be the format-specific prefix
|
|
if (unpadded_len < len) {
|
|
len--; // This should suffice for BASE_OCTAL
|
|
}
|
|
if (len && (base == BASE_HEX || base == BASE_BINARY) && (unpadded_len < len)) {
|
|
len--; // ... and an extra one for 0x or 0b
|
|
}
|
|
}
|
|
if ((base == BASE_HEX) && !(flags & FLAGS_UPPERCASE) && (len < PRINTF_INTEGER_BUFFER_SIZE)) {
|
|
buf[len++] = 'x';
|
|
} else if ((base == BASE_HEX) && (flags & FLAGS_UPPERCASE) && (len < PRINTF_INTEGER_BUFFER_SIZE)) {
|
|
buf[len++] = 'X';
|
|
} else if ((base == BASE_BINARY) && (len < PRINTF_INTEGER_BUFFER_SIZE)) {
|
|
buf[len++] = 'b';
|
|
}
|
|
if (len < PRINTF_INTEGER_BUFFER_SIZE) {
|
|
buf[len++] = '0';
|
|
}
|
|
}
|
|
|
|
if (len < PRINTF_INTEGER_BUFFER_SIZE) {
|
|
if (negative) {
|
|
buf[len++] = '-';
|
|
} else if (flags & FLAGS_PLUS) {
|
|
buf[len++] = '+'; // ignore the space if the '+' exists
|
|
} else if (flags & FLAGS_SPACE) {
|
|
buf[len++] = ' ';
|
|
}
|
|
}
|
|
|
|
out_rev_(output, putc_function, buf, len, width, flags);
|
|
}
|
|
|
|
// An internal itoa-like function
|
|
static void print_integer(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), printf_unsigned_value_t value, bool negative, numeric_base_t base, size_t precision, size_t width, printf_flags_t flags)
|
|
{
|
|
char buf[PRINTF_INTEGER_BUFFER_SIZE];
|
|
size_t len = 0U;
|
|
|
|
if (!value) {
|
|
if (!(flags & FLAGS_PRECISION)) {
|
|
buf[len++] = '0';
|
|
flags &= ~FLAGS_HASH;
|
|
// We drop this flag this since either the alternative and regular modes of the specifier
|
|
// don't differ on 0 values, or (in the case of octal) we've already provided the special
|
|
// handling for this mode.
|
|
} else if (base == BASE_HEX) {
|
|
flags &= ~FLAGS_HASH;
|
|
// We drop this flag this since either the alternative and regular modes of the specifier
|
|
// don't differ on 0 values
|
|
}
|
|
} else {
|
|
do {
|
|
const char digit = (char)(value % base);
|
|
buf[len++] = (char)(digit < 10 ? '0' + digit : (flags & FLAGS_UPPERCASE ? 'A' : 'a') + digit - 10);
|
|
value /= base;
|
|
} while (value && (len < PRINTF_INTEGER_BUFFER_SIZE));
|
|
}
|
|
|
|
print_integer_finalization(output, putc_function, buf, len, negative, base, precision, width, flags);
|
|
}
|
|
|
|
#if (CONFIG_VLIBC_FLOAT || CONFIG_VLIBC_FLOAT_EX)
|
|
|
|
// Stores a fixed-precision representation of a double relative
|
|
// to a fixed precision (which cannot be determined by examining this structure)
|
|
struct double_components {
|
|
int_fast64_t integral;
|
|
int_fast64_t fractional;
|
|
// ... truncation of the actual fractional part of the double value, scaled
|
|
// by the precision value
|
|
bool is_negative;
|
|
};
|
|
|
|
#define NUM_DECIMAL_DIGITS_IN_INT64_T 18
|
|
#define PRINTF_MAX_PRECOMPUTED_POWER_OF_10 NUM_DECIMAL_DIGITS_IN_INT64_T
|
|
static const double powers_of_10[NUM_DECIMAL_DIGITS_IN_INT64_T] = {
|
|
1e00, 1e01, 1e02, 1e03, 1e04, 1e05, 1e06, 1e07, 1e08,
|
|
1e09, 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17
|
|
};
|
|
|
|
#define PRINTF_MAX_SUPPORTED_PRECISION NUM_DECIMAL_DIGITS_IN_INT64_T - 1
|
|
|
|
// Break up a double number - which is known to be a finite non-negative number -
|
|
// into its base-10 parts: integral - before the decimal point, and fractional - after it.
|
|
// Taken the precision into account, but does not change it even internally.
|
|
static struct double_components get_components(double number, size_t precision)
|
|
{
|
|
struct double_components number_;
|
|
number_.is_negative = get_sign_bit(number);
|
|
double abs_number = (number_.is_negative) ? -number : number;
|
|
number_.integral = (int_fast64_t)abs_number;
|
|
double remainder = (abs_number - (double)number_.integral) * powers_of_10[precision];
|
|
number_.fractional = (int_fast64_t)remainder;
|
|
|
|
remainder -= (double)number_.fractional;
|
|
|
|
if (remainder > 0.5) {
|
|
++number_.fractional;
|
|
// handle rollover, e.g. case 0.99 with precision 1 is 1.0
|
|
if ((double)number_.fractional >= powers_of_10[precision]) {
|
|
number_.fractional = 0;
|
|
++number_.integral;
|
|
}
|
|
} else if ((remainder == 0.5) && ((number_.fractional == 0U) || (number_.fractional & 1U))) {
|
|
// if halfway, round up if odd OR if last digit is 0
|
|
++number_.fractional;
|
|
}
|
|
|
|
if (precision == 0U) {
|
|
remainder = abs_number - (double)number_.integral;
|
|
if ((!(remainder < 0.5) || (remainder > 0.5)) && (number_.integral & 1)) {
|
|
// exactly 0.5 and ODD, then round up
|
|
// 1.5 -> 2, but 2.5 -> 2
|
|
++number_.integral;
|
|
}
|
|
}
|
|
return number_;
|
|
}
|
|
|
|
#if CONFIG_VLIBC_FLOAT_EX
|
|
struct scaling_factor {
|
|
double raw_factor;
|
|
bool multiply; // if true, need to multiply by raw_factor; otherwise need to divide by it
|
|
};
|
|
|
|
static double apply_scaling(double num, struct scaling_factor normalization)
|
|
{
|
|
return normalization.multiply ? num * normalization.raw_factor : num / normalization.raw_factor;
|
|
}
|
|
|
|
static double unapply_scaling(double normalized, struct scaling_factor normalization)
|
|
{
|
|
return normalization.multiply ? normalized / normalization.raw_factor : normalized * normalization.raw_factor;
|
|
}
|
|
|
|
static struct scaling_factor update_normalization(struct scaling_factor sf, double extra_multiplicative_factor)
|
|
{
|
|
struct scaling_factor result;
|
|
if (sf.multiply) {
|
|
result.multiply = true;
|
|
result.raw_factor = sf.raw_factor * extra_multiplicative_factor;
|
|
} else {
|
|
int factor_exp2 = get_exp2(get_bit_access(sf.raw_factor));
|
|
int extra_factor_exp2 = get_exp2(get_bit_access(extra_multiplicative_factor));
|
|
|
|
// Divide the larger-exponent raw raw_factor by the smaller
|
|
if (PRINTF_ABS(factor_exp2) > PRINTF_ABS(extra_factor_exp2)) {
|
|
result.multiply = false;
|
|
result.raw_factor = sf.raw_factor / extra_multiplicative_factor;
|
|
} else {
|
|
result.multiply = true;
|
|
result.raw_factor = extra_multiplicative_factor / sf.raw_factor;
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
static struct double_components get_normalized_components(bool negative, size_t precision, double non_normalized, struct scaling_factor normalization, int floored_exp10)
|
|
{
|
|
struct double_components components;
|
|
components.is_negative = negative;
|
|
double scaled = apply_scaling(non_normalized, normalization);
|
|
|
|
bool close_to_representation_extremum = ((-floored_exp10 + (int)precision) >= DBL_MAX_10_EXP - 1);
|
|
if (close_to_representation_extremum) {
|
|
// We can't have a normalization factor which also accounts for the precision, i.e. moves
|
|
// some decimal digits into the mantissa, since it's unrepresentable, or nearly unrepresentable.
|
|
// So, we'll give up early on getting extra precision...
|
|
return get_components(negative ? -scaled : scaled, precision);
|
|
}
|
|
components.integral = (int_fast64_t)scaled;
|
|
double remainder = non_normalized - unapply_scaling((double)components.integral, normalization);
|
|
double prec_power_of_10 = powers_of_10[precision];
|
|
struct scaling_factor account_for_precision = update_normalization(normalization, prec_power_of_10);
|
|
double scaled_remainder = apply_scaling(remainder, account_for_precision);
|
|
double rounding_threshold = 0.5;
|
|
|
|
components.fractional = (int_fast64_t)scaled_remainder; // when precision == 0, the assigned value should be 0
|
|
scaled_remainder -= (double)components.fractional; //when precision == 0, this will not change scaled_remainder
|
|
|
|
components.fractional += (scaled_remainder >= rounding_threshold);
|
|
if (scaled_remainder == rounding_threshold) {
|
|
// banker's rounding: Round towards the even number (making the mean error 0)
|
|
components.fractional &= ~((int_fast64_t)0x1);
|
|
}
|
|
// handle rollover, e.g. the case of 0.99 with precision 1 becoming (0,100),
|
|
// and must then be corrected into (1, 0).
|
|
// Note: for precision = 0, this will "translate" the rounding effect from
|
|
// the fractional part to the integral part where it should actually be
|
|
// felt (as prec_power_of_10 is 1)
|
|
if ((double)components.fractional >= prec_power_of_10) {
|
|
components.fractional = 0;
|
|
++components.integral;
|
|
}
|
|
return components;
|
|
}
|
|
#endif // CONFIG_VLIBC_FLOAT_EX
|
|
|
|
static void print_broken_up_decimal(
|
|
struct double_components number_, output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), size_t precision,
|
|
size_t width, printf_flags_t flags, char *buf, size_t len)
|
|
{
|
|
if (precision != 0U) {
|
|
// do fractional part, as an unsigned number
|
|
|
|
size_t count = precision;
|
|
|
|
// %g/%G mandates we skip the trailing 0 digits...
|
|
if ((flags & FLAGS_ADAPT_EXP) && !(flags & FLAGS_HASH) && (number_.fractional > 0)) {
|
|
while (true) {
|
|
int_fast64_t digit = number_.fractional % 10U;
|
|
if (digit != 0) {
|
|
break;
|
|
}
|
|
--count;
|
|
number_.fractional /= 10U;
|
|
}
|
|
// ... and even the decimal point if there are no
|
|
// non-zero fractional part digits (see below)
|
|
}
|
|
|
|
if (number_.fractional > 0 || !(flags & FLAGS_ADAPT_EXP) || (flags & FLAGS_HASH)) {
|
|
while (len < PRINTF_DECIMAL_BUFFER_SIZE) {
|
|
--count;
|
|
buf[len++] = (char)('0' + number_.fractional % 10U);
|
|
if (!(number_.fractional /= 10U)) {
|
|
break;
|
|
}
|
|
}
|
|
// add extra 0s
|
|
while ((len < PRINTF_DECIMAL_BUFFER_SIZE) && (count > 0U)) {
|
|
buf[len++] = '0';
|
|
--count;
|
|
}
|
|
if (len < PRINTF_DECIMAL_BUFFER_SIZE) {
|
|
buf[len++] = '.';
|
|
}
|
|
}
|
|
} else {
|
|
if ((flags & FLAGS_HASH) && (len < PRINTF_DECIMAL_BUFFER_SIZE)) {
|
|
buf[len++] = '.';
|
|
}
|
|
}
|
|
|
|
// Write the integer part of the number (it comes after the fractional
|
|
// since the character order is reversed)
|
|
while (len < PRINTF_DECIMAL_BUFFER_SIZE) {
|
|
buf[len++] = (char)('0' + (number_.integral % 10));
|
|
if (!(number_.integral /= 10)) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// pad leading zeros
|
|
if (!(flags & FLAGS_LEFT) && (flags & FLAGS_ZEROPAD)) {
|
|
if (width && (number_.is_negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) {
|
|
width--;
|
|
}
|
|
while ((len < width) && (len < PRINTF_DECIMAL_BUFFER_SIZE)) {
|
|
buf[len++] = '0';
|
|
}
|
|
}
|
|
|
|
if (len < PRINTF_DECIMAL_BUFFER_SIZE) {
|
|
if (number_.is_negative) {
|
|
buf[len++] = '-';
|
|
} else if (flags & FLAGS_PLUS) {
|
|
buf[len++] = '+'; // ignore the space if the '+' exists
|
|
} else if (flags & FLAGS_SPACE) {
|
|
buf[len++] = ' ';
|
|
}
|
|
}
|
|
|
|
out_rev_(output, putc_function, buf, len, width, flags);
|
|
}
|
|
|
|
// internal ftoa for fixed decimal floating point
|
|
static void print_decimal_number(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), double number, size_t precision, size_t width, printf_flags_t flags, char *buf, size_t len)
|
|
{
|
|
struct double_components value_ = get_components(number, precision);
|
|
print_broken_up_decimal(value_, output, putc_function, precision, width, flags, buf, len);
|
|
}
|
|
|
|
#if CONFIG_VLIBC_FLOAT_EX
|
|
|
|
// A floor function - but one which only works for numbers whose
|
|
// floor value is representable by an int.
|
|
static int bastardized_floor(double x)
|
|
{
|
|
if (x >= 0) {
|
|
return (int)x;
|
|
}
|
|
int n = (int)x;
|
|
return (((double)n) == x) ? n : n - 1;
|
|
}
|
|
|
|
// Computes the base-10 logarithm of the input number - which must be an actual
|
|
// positive number (not infinity or NaN, nor a sub-normal)
|
|
static double log10_of_positive(double positive_number)
|
|
{
|
|
// The implementation follows David Gay (https://www.ampl.com/netlib/fp/dtoa.c).
|
|
//
|
|
// Since log_10 ( M * 2^x ) = log_10(M) + x , we can separate the components of
|
|
// our input number, and need only solve log_10(M) for M between 1 and 2 (as
|
|
// the base-2 mantissa is always 1-point-something). In that limited range, a
|
|
// Taylor series expansion of log10(x) should serve us well enough; and we'll
|
|
// take the mid-point, 1.5, as the point of expansion.
|
|
|
|
double_with_bit_access dwba = get_bit_access(positive_number);
|
|
// based on the algorithm by David Gay (https://www.ampl.com/netlib/fp/dtoa.c)
|
|
int exp2 = get_exp2(dwba);
|
|
// drop the exponent, so dwba.F comes into the range [1,2)
|
|
dwba.U = (dwba.U & (((double_uint_t)(1) << DOUBLE_STORED_MANTISSA_BITS) - 1U)) |
|
|
((double_uint_t)DOUBLE_BASE_EXPONENT << DOUBLE_STORED_MANTISSA_BITS);
|
|
double z = (dwba.F - 1.5);
|
|
return (
|
|
// Taylor expansion around 1.5:
|
|
0.1760912590556812420 // Expansion term 0: ln(1.5) / ln(10)
|
|
+ z * 0.2895296546021678851 // Expansion term 1: (M - 1.5) * 2/3 / ln(10)
|
|
#if PRINTF_LOG10_TAYLOR_TERMS > 2
|
|
- z * z * 0.0965098848673892950 // Expansion term 2: (M - 1.5)^2 * 2/9 / ln(10)
|
|
#if PRINTF_LOG10_TAYLOR_TERMS > 3
|
|
+ z * z * z * 0.0428932821632841311 // Expansion term 2: (M - 1.5)^3 * 8/81 / ln(10)
|
|
#endif
|
|
#endif
|
|
// exact log_2 of the exponent x, with logarithm base change
|
|
+ exp2 * 0.30102999566398119521 // = exp2 * log_10(2) = exp2 * ln(2)/ln(10)
|
|
);
|
|
}
|
|
|
|
static double pow10_of_int(int floored_exp10)
|
|
{
|
|
// A crude hack for avoiding undesired behavior with barely-normal or slightly-subnormal values.
|
|
if (floored_exp10 == DOUBLE_MAX_SUBNORMAL_EXPONENT_OF_10) {
|
|
return DOUBLE_MAX_SUBNORMAL_POWER_OF_10;
|
|
}
|
|
// Compute 10^(floored_exp10) but (try to) make sure that doesn't overflow
|
|
double_with_bit_access dwba;
|
|
int exp2 = bastardized_floor(floored_exp10 * 3.321928094887362 + 0.5);
|
|
const double z = floored_exp10 * 2.302585092994046 - exp2 * 0.6931471805599453;
|
|
const double z2 = z * z;
|
|
dwba.U = ((double_uint_t)(exp2) + DOUBLE_BASE_EXPONENT) << DOUBLE_STORED_MANTISSA_BITS;
|
|
// compute exp(z) using continued fractions,
|
|
// see https://en.wikipedia.org/wiki/Exponential_function#Continued_fractions_for_ex
|
|
dwba.F *= 1 + 2 * z / (2 - z + (z2 / (6 + (z2 / (10 + z2 / 14)))));
|
|
return dwba.F;
|
|
}
|
|
|
|
static void print_exponential_number(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), double number, size_t precision, size_t width, printf_flags_t flags, char *buf, size_t len)
|
|
{
|
|
const bool negative = get_sign_bit(number);
|
|
// This number will decrease gradually (by factors of 10) as we "extract" the exponent out of it
|
|
double abs_number = negative ? -number : number;
|
|
|
|
int floored_exp10;
|
|
bool abs_exp10_covered_by_powers_table;
|
|
struct scaling_factor normalization;
|
|
|
|
// Determine the decimal exponent
|
|
if (abs_number == 0.0) {
|
|
// TODO: This is a special-case for 0.0 (and -0.0); but proper handling is required for denormals more generally.
|
|
floored_exp10 = 0; // ... and no need to set a normalization factor or check the powers table
|
|
} else {
|
|
double exp10 = log10_of_positive(abs_number);
|
|
floored_exp10 = bastardized_floor(exp10);
|
|
double p10 = pow10_of_int(floored_exp10);
|
|
// correct for rounding errors
|
|
if (abs_number < p10) {
|
|
floored_exp10--;
|
|
p10 /= 10;
|
|
}
|
|
abs_exp10_covered_by_powers_table = PRINTF_ABS(floored_exp10) < PRINTF_MAX_PRECOMPUTED_POWER_OF_10;
|
|
normalization.raw_factor = abs_exp10_covered_by_powers_table ? powers_of_10[PRINTF_ABS(floored_exp10)] : p10;
|
|
}
|
|
|
|
// We now begin accounting for the widths of the two parts of our printed field:
|
|
// the decimal part after decimal exponent extraction, and the base-10 exponent part.
|
|
// For both of these, the value of 0 has a special meaning, but not the same one:
|
|
// a 0 exponent-part width means "don't print the exponent"; a 0 decimal-part width
|
|
// means "use as many characters as necessary".
|
|
|
|
bool fall_back_to_decimal_only_mode = false;
|
|
if (flags & FLAGS_ADAPT_EXP) {
|
|
int required_significant_digits = (precision == 0) ? 1 : (int)precision;
|
|
// Should we want to fall-back to "%f" mode, and only print the decimal part?
|
|
fall_back_to_decimal_only_mode = (floored_exp10 >= -4 && floored_exp10 < required_significant_digits);
|
|
// Now, let's adjust the precision
|
|
// This also decided how we adjust the precision value - as in "%g" mode,
|
|
// "precision" is the number of _significant digits_, and this is when we "translate"
|
|
// the precision value to an actual number of decimal digits.
|
|
int precision_ = fall_back_to_decimal_only_mode ?
|
|
(int)precision - 1 - floored_exp10 :
|
|
(int)precision - 1; // the presence of the exponent ensures only one significant digit comes before the decimal point
|
|
precision = (precision_ > 0 ? (unsigned)precision_ : 0U);
|
|
flags |= FLAGS_PRECISION; // make sure print_broken_up_decimal respects our choice above
|
|
}
|
|
|
|
normalization.multiply = (floored_exp10 < 0 && abs_exp10_covered_by_powers_table);
|
|
bool should_skip_normalization = (fall_back_to_decimal_only_mode || floored_exp10 == 0);
|
|
struct double_components decimal_part_components =
|
|
should_skip_normalization ?
|
|
get_components(negative ? -abs_number : abs_number, precision) :
|
|
get_normalized_components(negative, precision, abs_number, normalization, floored_exp10);
|
|
|
|
// Account for roll-over, e.g. rounding from 9.99 to 100.0 - which effects
|
|
// the exponent and may require additional tweaking of the parts
|
|
if (fall_back_to_decimal_only_mode) {
|
|
if ((flags & FLAGS_ADAPT_EXP) && floored_exp10 >= -1 && decimal_part_components.integral == powers_of_10[floored_exp10 + 1]) {
|
|
floored_exp10++; // Not strictly necessary, since floored_exp10 is no longer really used
|
|
precision--;
|
|
// ... and it should already be the case that decimal_part_components.fractional == 0
|
|
}
|
|
// TODO: What about rollover strictly within the fractional part?
|
|
} else {
|
|
if (decimal_part_components.integral >= 10) {
|
|
floored_exp10++;
|
|
decimal_part_components.integral = 1;
|
|
decimal_part_components.fractional = 0;
|
|
}
|
|
}
|
|
|
|
// the floored_exp10 format is "E%+03d" and largest possible floored_exp10 value for a 64-bit double
|
|
// is "307" (for 2^1023), so we set aside 4-5 characters overall
|
|
size_t exp10_part_width = fall_back_to_decimal_only_mode ? 0U : (PRINTF_ABS(floored_exp10) < 100) ? 4U :
|
|
5U;
|
|
|
|
size_t decimal_part_width =
|
|
((flags & FLAGS_LEFT) && exp10_part_width) ?
|
|
// We're padding on the right, so the width constraint is the exponent part's
|
|
// problem, not the decimal part's, so we'll use as many characters as we need:
|
|
0U :
|
|
// We're padding on the left; so the width constraint is the decimal part's
|
|
// problem. Well, can both the decimal part and the exponent part fit within our overall width?
|
|
((width > exp10_part_width) ?
|
|
// Yes, so we limit our decimal part's width.
|
|
// (Note this is trivially valid even if we've fallen back to "%f" mode)
|
|
width - exp10_part_width :
|
|
// No; we just give up on any restriction on the decimal part and use as many
|
|
// characters as we need
|
|
0U);
|
|
|
|
const size_t printed_exponential_start_pos = output->pos;
|
|
print_broken_up_decimal(decimal_part_components, output, putc_function, precision, decimal_part_width, flags, buf, len);
|
|
|
|
if (!fall_back_to_decimal_only_mode) {
|
|
putc_function(output, (flags & FLAGS_UPPERCASE) ? 'E' : 'e');
|
|
print_integer(output,
|
|
putc_function,
|
|
ABS_FOR_PRINTING(floored_exp10),
|
|
floored_exp10 < 0, 10, 0, exp10_part_width - 1,
|
|
FLAGS_ZEROPAD | FLAGS_PLUS);
|
|
if (flags & FLAGS_LEFT) {
|
|
// We need to right-pad with spaces to meet the width requirement
|
|
while (output->pos - printed_exponential_start_pos < width) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#endif // CONFIG_VLIBC_FLOAT_EX
|
|
|
|
static void print_floating_point(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), double value, size_t precision, size_t width, printf_flags_t flags, bool prefer_exponential)
|
|
{
|
|
char buf[PRINTF_DECIMAL_BUFFER_SIZE];
|
|
size_t len = 0U;
|
|
|
|
// test for special values
|
|
if (value != value) {
|
|
out_rev_(output, putc_function, "nan", 3, width, flags);
|
|
return;
|
|
}
|
|
if (value < -DBL_MAX) {
|
|
out_rev_(output, putc_function, "fni-", 4, width, flags);
|
|
return;
|
|
}
|
|
if (value > DBL_MAX) {
|
|
out_rev_(output, putc_function, (flags & FLAGS_PLUS) ? "fni+" : "fni", (flags & FLAGS_PLUS) ? 4U : 3U, width, flags);
|
|
return;
|
|
}
|
|
|
|
if (!prefer_exponential &&
|
|
((value > PRINTF_FLOAT_NOTATION_THRESHOLD) || (value < -PRINTF_FLOAT_NOTATION_THRESHOLD))) {
|
|
// The required behavior of standard printf is to print _every_ integral-part digit -- which could mean
|
|
// printing hundreds of characters, overflowing any fixed internal buffer and necessitating a more complicated
|
|
// implementation.
|
|
#if CONFIG_VLIBC_FLOAT_EX
|
|
print_exponential_number(output, putc_function, value, precision, width, flags, buf, len);
|
|
#endif
|
|
return;
|
|
}
|
|
|
|
// set default precision, if not set explicitly
|
|
if (!(flags & FLAGS_PRECISION)) {
|
|
precision = VLIBC_DEFAULT_FLOAT_PRECISION;
|
|
}
|
|
|
|
// limit precision so that our integer holding the fractional part does not overflow
|
|
while ((len < PRINTF_DECIMAL_BUFFER_SIZE) && (precision > PRINTF_MAX_SUPPORTED_PRECISION)) {
|
|
buf[len++] = '0'; // This respects the precision in terms of result length only
|
|
precision--;
|
|
}
|
|
|
|
#if CONFIG_VLIBC_FLOAT_EX
|
|
if (prefer_exponential)
|
|
print_exponential_number(output, putc_function, value, precision, width, flags, buf, len);
|
|
else
|
|
#endif
|
|
print_decimal_number(output, putc_function, value, precision, width, flags, buf, len);
|
|
}
|
|
|
|
#endif // (CONFIG_VLIBC_FLOAT || CONFIG_VLIBC_FLOAT_EX)
|
|
|
|
// Advances the format pointer past the flags, and returns the parsed flags
|
|
// due to the characters passed
|
|
static printf_flags_t parse_flags(const char **format)
|
|
{
|
|
printf_flags_t flags = 0U;
|
|
do {
|
|
switch (**format) {
|
|
case '0':
|
|
flags |= FLAGS_ZEROPAD;
|
|
(*format)++;
|
|
break;
|
|
case '-':
|
|
flags |= FLAGS_LEFT;
|
|
(*format)++;
|
|
break;
|
|
case '+':
|
|
flags |= FLAGS_PLUS;
|
|
(*format)++;
|
|
break;
|
|
case ' ':
|
|
flags |= FLAGS_SPACE;
|
|
(*format)++;
|
|
break;
|
|
case '#':
|
|
flags |= FLAGS_HASH;
|
|
(*format)++;
|
|
break;
|
|
default:
|
|
return flags;
|
|
}
|
|
} while (true);
|
|
}
|
|
|
|
// internal vsnprintf - used for implementing _all library functions
|
|
// Note: We don't like the C standard's parameter names, so using more informative parameter names
|
|
// here instead.
|
|
static int _vsnprintf(output_gadget_t *output, void (*putc_function)(output_gadget_t *, char), const char *format, va_list args)
|
|
{
|
|
// Note: The library only calls _vsnprintf() with output->pos being 0. However, it is
|
|
// possible to call this function with a non-zero pos value for some "remedial printing".
|
|
|
|
while (*format) {
|
|
// format specifier? %[flags][width][.precision][length]
|
|
if (*format != '%') {
|
|
putc_function(output, *format);
|
|
format++;
|
|
continue;
|
|
} else {
|
|
format++;
|
|
}
|
|
|
|
printf_flags_t flags = parse_flags(&format);
|
|
|
|
// evaluate width field
|
|
size_t width = 0U;
|
|
if (is_digit_(*format)) {
|
|
width = (size_t)atou_(&format);
|
|
} else if (*format == '*') {
|
|
const int w = va_arg(args, int);
|
|
if (w < 0) {
|
|
flags |= FLAGS_LEFT; // reverse padding
|
|
width = (size_t)-w;
|
|
} else {
|
|
width = (size_t)w;
|
|
}
|
|
format++;
|
|
}
|
|
|
|
// evaluate precision field
|
|
size_t precision = 0U;
|
|
if (*format == '.') {
|
|
flags |= FLAGS_PRECISION;
|
|
format++;
|
|
if (is_digit_(*format)) {
|
|
precision = (size_t)atou_(&format);
|
|
} else if (*format == '*') {
|
|
const int precision_ = va_arg(args, int);
|
|
precision = precision_ > 0 ? (size_t)precision_ : 0U;
|
|
format++;
|
|
}
|
|
}
|
|
|
|
// evaluate length field
|
|
switch (*format) {
|
|
case 'l':
|
|
flags |= FLAGS_LONG;
|
|
format++;
|
|
if (*format == 'l') {
|
|
flags |= FLAGS_LONG_LONG;
|
|
format++;
|
|
}
|
|
break;
|
|
case 'h':
|
|
flags |= FLAGS_SHORT;
|
|
format++;
|
|
if (*format == 'h') {
|
|
flags |= FLAGS_CHAR;
|
|
format++;
|
|
}
|
|
break;
|
|
case 't':
|
|
flags |= (sizeof(ptrdiff_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG);
|
|
format++;
|
|
break;
|
|
case 'j':
|
|
flags |= (sizeof(intmax_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG);
|
|
format++;
|
|
break;
|
|
case 'z':
|
|
flags |= (sizeof(size_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG);
|
|
format++;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
// evaluate specifier
|
|
switch (*format) {
|
|
case 'd':
|
|
case 'i':
|
|
case 'u':
|
|
case 'x':
|
|
case 'X':
|
|
case 'o':
|
|
case 'b': {
|
|
if (*format == 'd' || *format == 'i') {
|
|
flags |= FLAGS_SIGNED;
|
|
}
|
|
|
|
numeric_base_t base;
|
|
if (*format == 'x' || *format == 'X') {
|
|
base = BASE_HEX;
|
|
} else if (*format == 'o') {
|
|
base = BASE_OCTAL;
|
|
} else if (*format == 'b') {
|
|
base = BASE_BINARY;
|
|
} else {
|
|
base = BASE_DECIMAL;
|
|
flags &= ~FLAGS_HASH; // decimal integers have no alternative presentation
|
|
}
|
|
|
|
if (*format == 'X') {
|
|
flags |= FLAGS_UPPERCASE;
|
|
}
|
|
|
|
format++;
|
|
// ignore '0' flag when precision is given
|
|
if (flags & FLAGS_PRECISION) {
|
|
flags &= ~FLAGS_ZEROPAD;
|
|
}
|
|
|
|
if (flags & FLAGS_SIGNED) {
|
|
// A signed specifier: d, i or possibly I + bit size if enabled
|
|
|
|
if (flags & FLAGS_LONG_LONG) {
|
|
#if CONFIG_VLIBC_LONG_LONG
|
|
const long long value = va_arg(args, long long);
|
|
print_integer(output, putc_function, ABS_FOR_PRINTING(value), value < 0, base, precision, width, flags);
|
|
#endif
|
|
} else if (flags & FLAGS_LONG) {
|
|
const long value = va_arg(args, long);
|
|
print_integer(output, putc_function, ABS_FOR_PRINTING(value), value < 0, base, precision, width, flags);
|
|
} else {
|
|
// We never try to interpret the argument as something potentially-smaller than int,
|
|
// due to integer promotion rules: Even if the user passed a short int, short unsigned
|
|
// etc. - these will come in after promotion, as int's (or unsigned for the case of
|
|
// short unsigned when it has the same size as int)
|
|
const int value =
|
|
(flags & FLAGS_CHAR) ? (signed char)va_arg(args, int) :
|
|
(flags & FLAGS_SHORT) ? (short int)va_arg(args, int) :
|
|
va_arg(args, int);
|
|
print_integer(output, putc_function, ABS_FOR_PRINTING(value), value < 0, base, precision, width, flags);
|
|
}
|
|
} else {
|
|
// An unsigned specifier: u, x, X, o, b
|
|
|
|
flags &= ~(FLAGS_PLUS | FLAGS_SPACE);
|
|
|
|
if (flags & FLAGS_LONG_LONG) {
|
|
#if CONFIG_VLIBC_LONG_LONG
|
|
print_integer(output, putc_function, (printf_unsigned_value_t)va_arg(args, unsigned long long), false, base, precision, width, flags);
|
|
#endif
|
|
} else if (flags & FLAGS_LONG) {
|
|
print_integer(output, putc_function, (printf_unsigned_value_t)va_arg(args, unsigned long), false, base, precision, width, flags);
|
|
} else {
|
|
const unsigned int value =
|
|
(flags & FLAGS_CHAR) ? (unsigned char)va_arg(args, unsigned int) :
|
|
(flags & FLAGS_SHORT) ? (unsigned short int)va_arg(args, unsigned int) :
|
|
va_arg(args, unsigned int);
|
|
print_integer(output, putc_function, (printf_unsigned_value_t)value, false, base, precision, width, flags);
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
#if CONFIG_VLIBC_FLOAT
|
|
case 'f':
|
|
case 'F':
|
|
if (*format == 'F')
|
|
flags |= FLAGS_UPPERCASE;
|
|
print_floating_point(output, putc_function, va_arg(args, double), precision, width, flags, PRINTF_PREFER_DECIMAL);
|
|
format++;
|
|
break;
|
|
#endif
|
|
|
|
#if CONFIG_VLIBC_FLOAT_EX
|
|
case 'e':
|
|
case 'E':
|
|
case 'g':
|
|
case 'G':
|
|
if ((*format == 'g') || (*format == 'G'))
|
|
flags |= FLAGS_ADAPT_EXP;
|
|
if ((*format == 'E') || (*format == 'G'))
|
|
flags |= FLAGS_UPPERCASE;
|
|
print_floating_point(output, putc_function, va_arg(args, double), precision, width, flags, PRINTF_PREFER_EXPONENTIAL);
|
|
format++;
|
|
break;
|
|
#endif
|
|
|
|
case 'c': {
|
|
size_t l = 1U;
|
|
// pre padding
|
|
if (!(flags & FLAGS_LEFT)) {
|
|
while (l++ < width) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
// char output
|
|
putc_function(output, (char)va_arg(args, int));
|
|
// post padding
|
|
if (flags & FLAGS_LEFT) {
|
|
while (l++ < width) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
format++;
|
|
break;
|
|
}
|
|
|
|
case 's': {
|
|
const char *p = va_arg(args, char *);
|
|
if (p == NULL) {
|
|
out_rev_(output, putc_function, ")llun(", 6, width, flags);
|
|
} else {
|
|
size_t l = strnlen_s_(p, precision ? precision : PRINTF_MAX_POSSIBLE_BUFFER_SIZE);
|
|
// pre padding
|
|
if (flags & FLAGS_PRECISION) {
|
|
l = (l < precision ? l : precision);
|
|
}
|
|
if (!(flags & FLAGS_LEFT)) {
|
|
while (l++ < width) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
// string output
|
|
while ((*p != 0) && (!(flags & FLAGS_PRECISION) || precision)) {
|
|
putc_function(output, *(p++));
|
|
--precision;
|
|
}
|
|
// post padding
|
|
if (flags & FLAGS_LEFT) {
|
|
while (l++ < width) {
|
|
putc_function(output, ' ');
|
|
}
|
|
}
|
|
}
|
|
format++;
|
|
break;
|
|
}
|
|
|
|
case 'p': {
|
|
width = sizeof(void *) * 2U + 2; // 2 hex chars per byte + the "0x" prefix
|
|
flags |= FLAGS_ZEROPAD | FLAGS_POINTER;
|
|
uintptr_t value = (uintptr_t)va_arg(args, void *);
|
|
(value == (uintptr_t)NULL) ?
|
|
out_rev_(output, putc_function, ")lin(", 5, width, flags) :
|
|
print_integer(output, putc_function, (printf_unsigned_value_t)value, false, BASE_HEX, precision, width, flags);
|
|
format++;
|
|
break;
|
|
}
|
|
|
|
case '%':
|
|
putc_function(output, '%');
|
|
format++;
|
|
break;
|
|
|
|
// Many people prefer to disable support for %n, as it lets the caller
|
|
// engineer a write to an arbitrary location, of a value the caller
|
|
// effectively controls - which could be a security concern in some cases.
|
|
#if CONFIG_VLIBC_WRITEBACK
|
|
case 'n': {
|
|
if (flags & FLAGS_CHAR)
|
|
*(va_arg(args, char *)) = (char)output->pos;
|
|
else if (flags & FLAGS_SHORT)
|
|
*(va_arg(args, short *)) = (short)output->pos;
|
|
else if (flags & FLAGS_LONG)
|
|
*(va_arg(args, long *)) = (long)output->pos;
|
|
#if CONFIG_VLIBC_LONG_LONG
|
|
else if (flags & FLAGS_LONG_LONG)
|
|
*(va_arg(args, long long *)) = (long long int)output->pos;
|
|
#endif // CONFIG_VLIBC_LONG_LONG
|
|
else
|
|
*(va_arg(args, int *)) = (int)output->pos;
|
|
format++;
|
|
break;
|
|
}
|
|
#endif // CONFIG_VLIBC_WRITEBACK
|
|
|
|
default:
|
|
putc_function(output, *format);
|
|
format++;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// termination append \0
|
|
if ((output->stream == NULL) && (output->buffer != NULL) && (output->max > 0)) {
|
|
size_t null_char_pos = output->pos < output->max ? output->pos : output->max - 1;
|
|
output->buffer[null_char_pos] = '\0';
|
|
}
|
|
|
|
// return written chars without terminating \0
|
|
return (int)output->pos;
|
|
}
|
|
|
|
/** @addtogroup api **********************************************************
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* @brief
|
|
* @param stream
|
|
* @param format
|
|
* @param arg
|
|
* @return int
|
|
*/
|
|
// int vfprintf(FILE *__restrict, const char *__restrict, __VALIST) __attribute__((alias("vlibc_vfprintf")));
|
|
int vlibc_vfprintf(VLIBC_FILE *stream, const char *format, va_list arg)
|
|
{
|
|
CHECK_FILE(stream, EOF);
|
|
CHECK_FILE(format, EOF);
|
|
|
|
output_gadget_t gadget;
|
|
gadget.stream = stream;
|
|
gadget.buffer = NULL;
|
|
gadget.pos = 0;
|
|
gadget.max = PRINTF_MAX_POSSIBLE_BUFFER_SIZE;
|
|
|
|
IF_IO_DEV(stream)
|
|
{
|
|
switch (stream->io->vbuf) {
|
|
case _IOFBF:
|
|
if (stream->io->wp == stream->io->ed) {
|
|
if (__vlibc_io_mem2dev(stream->io, stream->io->bg, stream->io->ed - stream->io->bg) == 0) {
|
|
errno = EINVAL;
|
|
}
|
|
stream->io->wp = stream->io->bg;
|
|
}
|
|
return _vsnprintf(&gadget, putc_via_iodev_fbf, format, arg);
|
|
case _IOLBF:
|
|
if (stream->io->wp == stream->io->ed) {
|
|
if (__vlibc_io_mem2dev(stream->io, stream->io->bg, stream->io->ed - stream->io->bg) == 0) {
|
|
errno = EINVAL;
|
|
}
|
|
stream->io->wp = stream->io->bg;
|
|
}
|
|
return _vsnprintf(&gadget, putc_via_iodev_lbf, format, arg);
|
|
case _IONBF:
|
|
return _vsnprintf(&gadget, putc_via_iodev_nbf, format, arg);
|
|
default:
|
|
errno = EINVAL;
|
|
return EOF;
|
|
}
|
|
}
|
|
else IF_FILE(stream)
|
|
{
|
|
#ifdef CONFIG_VLIBC_FATFS
|
|
char buffer[VLIBC_FBUFSIZ];
|
|
int ret;
|
|
FRESULT fresult;
|
|
size_t bytes;
|
|
|
|
gadget.buffer = buffer;
|
|
gadget.max = 0;
|
|
|
|
ret = _vsnprintf(&gadget, putc_via_file, format, arg);
|
|
|
|
fresult = f_write(stream->file, buffer, gadget.max, &bytes);
|
|
if (fresult != FR_OK) {
|
|
if (fresult <= FR_INVALID_PARAMETER) {
|
|
errno = FRESULT_to_errno[fresult];
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
#else
|
|
return EOF;
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
errno = EINVAL;
|
|
return EOF;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param format
|
|
* @param arg
|
|
* @return int
|
|
*/
|
|
// int vprintf(const char *, __VALIST) __attribute__((alias("vlibc_vprintf")));
|
|
int vlibc_vprintf(const char *format, va_list arg)
|
|
{
|
|
return vlibc_vfprintf(vlibc_stdout, format, arg);
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param str
|
|
* @param size
|
|
* @param format
|
|
* @param arg
|
|
* @return int
|
|
*/
|
|
int vsnprintf(char *__restrict, size_t, const char *__restrict, __VALIST) __attribute__((alias("vlibc_vsnprintf")));
|
|
int vlibc_vsnprintf(char *str, size_t size, const char *format, va_list arg)
|
|
{
|
|
CHECK_FILE(str, EOF);
|
|
CHECK_FILE(format, EOF);
|
|
|
|
output_gadget_t gadget;
|
|
gadget.stream = NULL;
|
|
gadget.buffer = str;
|
|
gadget.pos = 0;
|
|
gadget.max = size;
|
|
return _vsnprintf(&gadget, putc_via_buffer, format, arg);
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param str
|
|
* @param format
|
|
* @param arg
|
|
* @return int
|
|
*/
|
|
// int vsprintf(char *__restrict, const char *__restrict, __VALIST) __attribute__((alias("vlibc_vsprintf")));
|
|
int vlibc_vsprintf(char *str, const char *format, va_list arg)
|
|
{
|
|
return vlibc_vsnprintf(str, PRINTF_MAX_POSSIBLE_BUFFER_SIZE, format, arg);
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param stream
|
|
* @param format
|
|
* @param ...
|
|
* @return int
|
|
*/
|
|
// int fprintf(FILE *__restrict, const char *__restrict, ...) __attribute__((alias("vlibc_fprintf")));
|
|
int vlibc_fprintf(VLIBC_FILE *stream, const char *format, ...)
|
|
{
|
|
va_list args;
|
|
va_start(args, format);
|
|
const int ret = vlibc_vfprintf(stream, format, args);
|
|
va_end(args);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param format
|
|
* @param ...
|
|
* @return int
|
|
*/
|
|
int printf(const char *__restrict, ...) __attribute__((alias("vlibc_printf")));
|
|
int vlibc_printf(const char *format, ...)
|
|
{
|
|
va_list args;
|
|
va_start(args, format);
|
|
const int ret = vlibc_vprintf(format, args);
|
|
va_end(args);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param str
|
|
* @param format
|
|
* @param ...
|
|
* @return int
|
|
*/
|
|
// int sprintf(char *__restrict, const char *__restrict, ...) __attribute__((alias("vlibc_sprintf")));
|
|
int vlibc_sprintf(char *str, const char *format, ...)
|
|
{
|
|
va_list args;
|
|
va_start(args, format);
|
|
const int ret = vlibc_vsprintf(str, format, args);
|
|
va_end(args);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* @param str
|
|
* @param size
|
|
* @param format
|
|
* @param ...
|
|
* @return int
|
|
*/
|
|
// int snprintf(char *__restrict, size_t, const char *__restrict, ...) __attribute__((alias("vlibc_snprintf")));
|
|
int vlibc_snprintf(char *str, size_t size, const char *format, ...)
|
|
{
|
|
va_list args;
|
|
va_start(args, format);
|
|
const int ret = vlibc_vsnprintf(str, size, format, args);
|
|
va_end(args);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* @}
|
|
*/
|