sortix-mirror/libc/stdio/vcbprintf.c
Jonas 'Sortie' Termansen 2b72262b4f Relicense Sortix to the ISC license.
I hereby relicense all my work on Sortix under the ISC license as below.

All Sortix contributions by other people are already under this license,
are not substantial enough to be copyrightable, or have been removed.

All imported code from other projects is compatible with this license.

All GPL licensed code from other projects had previously been removed.

Copyright 2011-2016 Jonas 'Sortie' Termansen and contributors.

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
2016-03-05 22:21:50 +01:00

489 lines
13 KiB
C

/*
* Copyright (c) 2011, 2012, 2013, 2014, 2015 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* stdio/vcbprintf.c
* Formats text and outputs it via callback functions.
*/
#include <errno.h>
#include <limits.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
static size_t convert_integer(char* destination, uintmax_t value,
uintmax_t base, const char* digits)
{
size_t result = 1;
uintmax_t copy = value;
while ( base <= copy )
copy /= base, result++;
for ( size_t i = result; i != 0; i-- )
{
destination[i-1] = digits[value % base];
value /= base;
}
return result;
}
static size_t noop_callback(void* ctx, const char* str, size_t amount)
{
(void) ctx;
(void) str;
return amount;
}
int vcbprintf(void* ctx,
size_t (*callback)(void*, const char*, size_t),
const char* format,
va_list parameters)
{
if ( !callback )
callback = noop_callback;
size_t written = 0;
bool rejected_bad_specifier = false;
while ( *format != '\0' )
{
if ( *format != '%' )
{
size_t amount;
print_c:
amount = 1;
while ( format[amount] && format[amount] != '%' )
amount++;
if ( callback(ctx, format, amount) != amount )
return -1;
format += amount;
written += amount;
continue;
}
const char* format_begun_at = format;
if ( *(++format) == '%' )
goto print_c;
if ( rejected_bad_specifier )
{
incomprehensible_conversion:
rejected_bad_specifier = true;
unsupported_conversion:
format = format_begun_at;
goto print_c;
}
bool alternate = false;
bool zero_pad = false;
bool field_width_is_negative = false;
bool prepend_blank_if_positive = false;
bool prepend_plus_if_positive = false;
bool group_thousands = false;
bool alternate_output_digits = false;
while ( true )
{
switch ( *format++ )
{
case '#': alternate = true; continue;
case '0': zero_pad = true; continue;
case '-': field_width_is_negative = true; continue;
case ' ': prepend_blank_if_positive = true; continue;
case '+': prepend_plus_if_positive = true; continue;
case '\'': group_thousands = true; continue;
case 'I': alternate_output_digits = true; continue;
default: format--; break;
}
break;
}
(void) group_thousands;
(void) alternate_output_digits;
int field_width = 0;
if ( *format == '*' && (format++, true) )
field_width = va_arg(parameters, int);
else while ( '0' <= *format && *format <= '9' )
field_width = 10 * field_width + *format++ - '0';
if ( field_width_is_negative )
field_width = -field_width;
size_t abs_field_width = (size_t) abs(field_width);
size_t precision = SIZE_MAX;
if ( *format == '.' && (format++, true) )
{
precision = 0;
if ( *format == '*' && (format++, true) )
{
int int_precision = va_arg(parameters, int);
precision = 0 <= int_precision ? (size_t) int_precision : 0;
}
else if ( *format == '-' && (format++, true) )
{
while ( '0' <= *format && *format <= '9' )
format++;
}
else
{
while ( '0' <= *format && *format <= '9' )
precision = 10 * precision + *format++ - '0';
}
}
enum length
{
LENGTH_SHORT_SHORT,
LENGTH_SHORT,
LENGTH_DEFAULT,
LENGTH_LONG,
LENGTH_LONG_LONG,
LENGTH_LONG_DOUBLE,
LENGTH_INTMAX_T,
LENGTH_SIZE_T,
LENGTH_PTRDIFF_T,
};
struct length_modifer
{
const char* name;
enum length length;
};
struct length_modifer length_modifiers[] =
{
{ "hh", LENGTH_SHORT_SHORT },
{ "h", LENGTH_SHORT },
{ "", LENGTH_DEFAULT },
{ "l", LENGTH_LONG },
{ "ll", LENGTH_LONG_LONG },
{ "L", LENGTH_LONG_DOUBLE },
{ "j", LENGTH_INTMAX_T },
{ "z", LENGTH_SIZE_T },
{ "t", LENGTH_PTRDIFF_T },
};
enum length length = LENGTH_DEFAULT;
size_t length_length = 0;
for ( size_t i = 0;
i < sizeof(length_modifiers) / sizeof(length_modifiers[0]);
i++ )
{
size_t name_length = strlen(length_modifiers[i].name);
if ( name_length < length_length )
continue;
if ( strncmp(format, length_modifiers[i].name, name_length) != 0 )
continue;
length = length_modifiers[i].length;
length_length = name_length;
}
format += length_length;
if ( *format == 'd' || *format == 'i' || *format == 'o' ||
*format == 'u' || *format == 'x' || *format == 'X' ||
*format == 'p' )
{
char conversion = *format++;
bool negative_value = false;
uintmax_t value;
if ( conversion == 'p' )
{
value = (uintptr_t) va_arg(parameters, void*);
conversion = 'x';
alternate = !alternate;
prepend_blank_if_positive = false;
prepend_plus_if_positive = false;
}
else if ( conversion == 'i' || conversion == 'd' )
{
intmax_t signed_value;
if ( length == LENGTH_SHORT_SHORT )
signed_value = va_arg(parameters, int);
else if ( length == LENGTH_SHORT )
signed_value = va_arg(parameters, int);
else if ( length == LENGTH_DEFAULT )
signed_value = va_arg(parameters, int);
else if ( length == LENGTH_LONG )
signed_value = va_arg(parameters, long);
else if ( length == LENGTH_LONG_LONG )
signed_value = va_arg(parameters, long long);
else if ( length == LENGTH_INTMAX_T )
signed_value = va_arg(parameters, intmax_t);
else if ( length == LENGTH_SIZE_T )
signed_value = va_arg(parameters, ssize_t);
else if ( length == LENGTH_PTRDIFF_T )
signed_value = va_arg(parameters, ptrdiff_t);
else
goto incomprehensible_conversion;
value = (negative_value = signed_value < 0) ?
- (uintmax_t) signed_value : (uintmax_t) signed_value;
}
else
{
if ( length == LENGTH_SHORT_SHORT )
value = va_arg(parameters, unsigned int);
else if ( length == LENGTH_SHORT )
value = va_arg(parameters, unsigned int);
else if ( length == LENGTH_DEFAULT )
value = va_arg(parameters, unsigned int);
else if ( length == LENGTH_LONG )
value = va_arg(parameters, unsigned long);
else if ( length == LENGTH_LONG_LONG )
value = va_arg(parameters, unsigned long long);
else if ( length == LENGTH_INTMAX_T )
value = va_arg(parameters, uintmax_t);
else if ( length == LENGTH_SIZE_T )
value = va_arg(parameters, size_t);
else if ( length == LENGTH_PTRDIFF_T )
value = (uintmax_t) va_arg(parameters, ptrdiff_t);
else
goto incomprehensible_conversion;
prepend_blank_if_positive = false;
prepend_plus_if_positive = false;
}
const char* digits = conversion == 'X' ? "0123456789ABCDEF" :
"0123456789abcdef";
uintmax_t base = (conversion == 'x' || conversion == 'X') ? 16 :
conversion == 'o' ? 8 : 10;
char prefix[3];
size_t prefix_length = 0;
size_t prefix_digits_length = 0;
if ( negative_value )
prefix[prefix_length++] = '-';
else if ( prepend_plus_if_positive )
prefix[prefix_length++] = '+';
else if ( prepend_blank_if_positive )
prefix[prefix_length++] = ' ';
if ( alternate && (conversion == 'x' || conversion == 'X') && value != 0 )
{
prefix[prefix_digits_length++, prefix_length++] = '0';
prefix[prefix_digits_length++, prefix_length++] = conversion;
}
if ( alternate && conversion == 'o' && value != 0 )
prefix[prefix_digits_length++, prefix_length++] = '0';
char output[sizeof(uintmax_t) * 3];
size_t output_length = convert_integer(output, value, base, digits);
if ( !precision && output_length == 1 && output[0] == '0' )
{
output_length = 0;
output[0] = '\0';
}
size_t output_length_with_precision =
precision != SIZE_MAX && output_length < precision ?
precision :
output_length;
size_t digits_length = prefix_digits_length + output_length;
size_t normal_length = prefix_length + output_length;
size_t length_with_precision = prefix_length + output_length_with_precision;
bool use_precision = precision != SIZE_MAX;
bool use_zero_pad = zero_pad && 0 <= field_width && !use_precision;
bool use_left_pad = !use_zero_pad && 0 <= field_width;
bool use_right_pad = !use_zero_pad && field_width < 0;
if ( use_left_pad )
{
for ( size_t i = length_with_precision; i < abs_field_width; i++ )
{
if ( callback(ctx, " ", 1) != 1 )
return -1;
written++;
}
}
if ( callback(ctx, prefix, prefix_length) != prefix_length )
return -1;
written += prefix_length;
if ( use_zero_pad )
{
for ( size_t i = normal_length; i < abs_field_width; i++ )
{
if ( callback(ctx, "0", 1) != 1 )
return -1;
written++;
}
}
if ( use_precision )
{
for ( size_t i = digits_length; i < precision; i++ )
{
if ( callback(ctx, "0", 1) != 1 )
return -1;
written++;
}
}
if ( callback(ctx, output, output_length) != output_length )
return -1;
written += output_length;
if ( use_right_pad )
{
for ( size_t i = length_with_precision; i < abs_field_width; i++ )
{
if ( callback(ctx, " ", 1) != 1 )
return -1;
written++;
}
}
}
#ifndef __is_sortix_libk
else if ( *format == 'e' || *format == 'E' ||
*format == 'f' || *format == 'F' ||
*format == 'g' || *format == 'G' ||
*format == 'a' || *format == 'A' )
{
char conversion = *format++;
long double value;
if ( length == LENGTH_DEFAULT )
value = va_arg(parameters, double);
else if ( length == LENGTH_LONG_DOUBLE )
value = va_arg(parameters, long double);
else
goto incomprehensible_conversion;
// TODO: Implement floating-point printing.
(void) conversion;
(void) value;
goto unsupported_conversion;
}
#endif
else if ( *format == 'c' && (format++, true) )
{
char c;
if ( length == LENGTH_DEFAULT )
c = (char) va_arg(parameters, int);
else if ( length == LENGTH_LONG )
{
// TODO: Implement wide character printing.
(void) va_arg(parameters, wint_t);
goto unsupported_conversion;
}
else
goto incomprehensible_conversion;
if ( !field_width_is_negative && 1 < abs_field_width )
{
for ( size_t i = 1; i < abs_field_width; i++ )
{
if ( callback(ctx, " ", 1) != 1 )
return -1;
written++;
}
}
if ( callback(ctx, &c, 1) != 1 )
return -1;
written++;
if ( field_width_is_negative && 1 < abs_field_width )
{
for ( size_t i = 1; i < abs_field_width; i++ )
{
if ( callback(ctx, " ", 1) != 1 )
return -1;
written++;
}
}
}
else if ( *format == 'm' || *format == 's' )
{
char conversion = *format++;
const char* string;
if ( conversion == 'm' )
string = strerror(errno), conversion = 's';
else if ( length == LENGTH_DEFAULT )
string = va_arg(parameters, const char*);
else if ( length == LENGTH_LONG )
{
// TODO: Implement wide character string printing.
(void) va_arg(parameters, const wchar_t*);
goto unsupported_conversion;
}
else
goto incomprehensible_conversion;
if ( conversion == 's' && !string )
string = "(null)";
size_t string_length = 0;
for ( size_t i = 0; i < precision && string[i]; i++ )
string_length++;
if ( !field_width_is_negative && string_length < abs_field_width )
{
for ( size_t i = string_length; i < abs_field_width; i++ )
{
if ( callback(ctx, " ", 1) != 1 )
return -1;
written++;
}
}
if ( callback(ctx, string, string_length) != string_length )
return -1;
written += string_length;
if ( field_width_is_negative && string_length < abs_field_width )
{
for ( size_t i = string_length; i < abs_field_width; i++ )
{
if ( callback(ctx, " ", 1) != 1 )
return -1;
written++;
}
}
}
else if ( *format == 'n' && (format++, true) )
{
if ( length == LENGTH_SHORT_SHORT )
*va_arg(parameters, signed char*) = (signed char) written;
else if ( length == LENGTH_SHORT )
*va_arg(parameters, short*) = (short) written;
else if ( length == LENGTH_DEFAULT )
*va_arg(parameters, int*) = (int) written;
else if ( length == LENGTH_LONG )
*va_arg(parameters, long*) = (long) written;
else if ( length == LENGTH_LONG_LONG )
*va_arg(parameters, long long*) = (long long) written;
else if ( length == LENGTH_INTMAX_T )
*va_arg(parameters, uintmax_t*) = (uintmax_t) written;
else if ( length == LENGTH_SIZE_T )
*va_arg(parameters, size_t*) = (size_t) written;
else if ( length == LENGTH_PTRDIFF_T )
*va_arg(parameters, ptrdiff_t*) = (ptrdiff_t) written;
else
goto incomprehensible_conversion;
}
else
goto incomprehensible_conversion;
}
if ( INT_MAX < written )
return -1;
return written;
}