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Rewrite vprintf_callback(3).

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This commit is contained in:
Jonas 'Sortie' Termansen 2013-10-21 02:00:59 +02:00
parent 26add4c111
commit 011ea58176
3 changed files with 409 additions and 528 deletions
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2
libc/Makefile
View file

@ -56,7 +56,6 @@ stdio/flbf.o \
stdio/flockfile.o \ stdio/flockfile.o \
stdio/flushlbf.o \ stdio/flushlbf.o \
stdio/fnewfile.o \ stdio/fnewfile.o \
stdio/format.o \
stdio/fpending.o \ stdio/fpending.o \
stdio/fpurge.o \ stdio/fpurge.o \
stdio/fputc.o \ stdio/fputc.o \
@ -91,6 +90,7 @@ stdio/sscanf.o \
stdio/ungetc.o \ stdio/ungetc.o \
stdio/vdprintf.o \ stdio/vdprintf.o \
stdio/vfscanf.o \ stdio/vfscanf.o \
stdio/vprintf_callback.o \
stdio/vsnprintf.o \ stdio/vsnprintf.o \
stdio/vsprintf.o \ stdio/vsprintf.o \
stdio/vsscanf.o \ stdio/vsscanf.o \

527
libc/stdio/format.cpp
View file

@ -1,527 +0,0 @@
/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
This file is part of the Sortix C Library.
The Sortix C Library is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
The Sortix C Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
stdio/format.cpp
Provides printf formatting functions that uses callbacks.
*******************************************************************************/
// Number of bugs seemingly unrelated bugs that have been traced to here:
// Countless + 2
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
namespace String {
static int ConvertInt32(int32_t num, char* dest, char possign)
{
int result = 0;
int32_t copy = num;
if ( num < 0 )
{
*dest++ = '-';
result++;
int offset = 0;
while ( copy < -9 ) { copy /= 10; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' - num % 10; num /= 10; offset--;
}
}
else
{
if ( possign )
*dest++ = possign,
result++;
int offset = 0;
while ( copy > 9 ) { copy /= 10; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' + num % 10; num /= 10; offset--;
}
}
return result + 1;
}
static int ConvertInt64(int64_t num, char* dest, char possign)
{
int result = 0;
int64_t copy = num;
if ( num < 0 )
{
*dest++ = '-';
result++;
int offset = 0;
while ( copy < -9 ) { copy /= 10; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' - num % 10; num /= 10; offset--;
}
}
else
{
if ( possign )
*dest++ = possign,
result++;
int offset = 0;
while ( copy > 9 ) { copy /= 10; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' + num % 10; num /= 10; offset--;
}
}
return result + 1;
}
static int ConvertUInt32(uint32_t num, char* dest)
{
int result = 0;
uint32_t copy = num;
int offset = 0;
while ( copy > 9 ) { copy /= 10; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' + num % 10; num /= 10; offset--;
}
return result + 1;
}
static int ConvertUInt64(uint64_t num, char* dest)
{
int result = 0;
uint64_t copy = num;
int offset = 0;
while ( copy > 9 ) { copy /= 10; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' + num % 10; num /= 10; offset--;
}
return result + 1;
}
static int ConvertUInt32Octal(uint32_t num, char* dest)
{
int result = 0;
uint32_t copy = num;
int offset = 0;
while ( copy > 7 ) { copy /= 8; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' + num % 8; num /= 8; offset--;
}
return result + 1;
}
static int ConvertUInt64Octal(uint64_t num, char* dest)
{
int result = 0;
uint64_t copy = num;
int offset = 0;
while ( copy > 7 ) { copy /= 8; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = '0' + num % 8; num /= 8; offset--;
}
return result + 1;
}
static int ConvertUInt32Hex(uint32_t num, char* dest)
{
char chars[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'A', 'B', 'C', 'D', 'E', 'F' };
int result = 0;
uint32_t copy = num;
int offset = 0;
while ( copy > 15 ) { copy /= 16; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = chars[num % 16]; num /= 16; offset--;
}
return result + 1;
}
static int ConvertUInt64Hex(uint64_t num, char* dest)
{
char chars[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'A', 'B', 'C', 'D', 'E', 'F' };
int result = 0;
uint64_t copy = num;
int offset = 0;
while ( copy > 15 ) { copy /= 16; offset++; }
result += offset;
while ( offset >= 0 )
{
dest[offset] = chars[num % 16]; num /= 16; offset--;
}
return result + 1;
}
} // namespace String
#define READY_SIZE 128
#define READY_FLUSH() \
ready[readylen] = '\0'; \
if ( 0 < readylen && callback && callback(user, ready, readylen) != readylen ) { return SIZE_MAX; } \
written += readylen; readylen = 0;
#define REPEAT_BLANKS(num) \
for ( unsigned int i = 0; i < (num); i++ ) \
{ \
if ( readylen == READY_SIZE ) { READY_FLUSH(); } \
ready[readylen++ + i - i] = blank_char; \
}
extern "C" size_t vprintf_callback(size_t (*callback)(void*, const char*, size_t),
void* user,
const char* restrict format,
va_list parameters)
{
size_t written = 0;
size_t readylen = 0;
char ready[READY_SIZE + 1];
while ( *format != '\0' )
{
char c = *format++;
if ( c != '%' )
{
print_c:
if ( READY_SIZE <= readylen ) { READY_FLUSH(); }
ready[readylen++] = c;
continue;
}
if ( *format == '%' )
{
c = *format++;
goto print_c;
}
const char* format_begun_at = format;
if ( false )
{
unsupported_conversion:
format = format_begun_at;
c = '%';
goto print_c;
}
const unsigned UNSIGNED = 0;
const unsigned INTEGER = (1<<0);
const unsigned BIT64 = (1<<1);
const unsigned HEX = (1<<2);
const unsigned OCTAL = (1<<3);
const unsigned STRING = 16;
const unsigned CHARACTER = 17;
#if defined(__x86_64__)
const unsigned WORDWIDTH = BIT64;
#else
const unsigned WORDWIDTH = 0;
#endif
// TODO: Support signed datatypes!
unsigned type = 0;
bool prepend_chars = false;
bool append_chars = false;
bool space_pad = false;
bool zero_pad = false;
bool alternate = false;
bool possign_space = false;
bool possign_plus = false;
char blank_char = ' ';
unsigned int field_width = 0;
bool scanning = true;
while ( scanning )
{
switch ( char c = *(format++) )
{
case ' ':
possign_space = true;
break;
case '+':
possign_plus = true;
break;
case '#':
alternate = true;
break;
case '-':
if ( prepend_chars || append_chars )
goto unsupported_conversion;
append_chars = space_pad = true;
prepend_chars = zero_pad = false;
blank_char = ' ';
break;
case '*':
if ( !(prepend_chars || append_chars) )
prepend_chars = true;
field_width = (unsigned int) va_arg(parameters, int);
break;
case '0':
if ( !(prepend_chars || append_chars) || (!field_width && space_pad) )
{
prepend_chars = zero_pad = true;
append_chars = space_pad = false;
blank_char = '0';
break;
}
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if ( !(prepend_chars || append_chars) )
prepend_chars = true;
field_width = field_width * 10 + c - '0';
break;
case 'p':
type = WORDWIDTH | HEX;
scanning = false;
break;
case 't':
type |= INTEGER;
case 'z':
case 'l':
if ( type & WORDWIDTH ) { type |= BIT64; }
type |= WORDWIDTH;
break;
case 'j':
type |= BIT64;
break;
case 'u':
type |= UNSIGNED;
scanning = false;
break;
case 'd':
case 'i':
type |= INTEGER;
scanning = false;
break;
case 'o':
type |= OCTAL;
scanning = false;
break;
case 'x':
case 'X':
type |= HEX;
scanning = false;
break;
case 's':
type = STRING;
scanning = false;
break;
case 'c':
type = CHARACTER;
scanning = false;
break;
default:
goto unsupported_conversion;
}
}
char possign = '\0';
if ( possign_plus )
possign = '+';
else if ( possign_space )
possign = ' ';
switch ( type )
{
case INTEGER:
{
if ( READY_SIZE - readylen < 10 ) { READY_FLUSH(); }
int32_t num = va_arg(parameters, int32_t);
size_t chars = String::ConvertInt32(num, ready + readylen, possign);
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 10 ) { READY_FLUSH(); }
String::ConvertInt32(num, ready + readylen, possign);
readylen += chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case UNSIGNED:
{
if ( READY_SIZE - readylen < 10 ) { READY_FLUSH(); }
uint32_t num = va_arg(parameters, uint32_t);
size_t chars = String::ConvertUInt32(num, ready + readylen);
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 10 ) { READY_FLUSH(); }
String::ConvertUInt32(num, ready + readylen);
readylen += chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case INTEGER | BIT64:
{
if ( READY_SIZE - readylen < 20 ) { READY_FLUSH(); }
int64_t num = va_arg(parameters, int64_t);
size_t chars = String::ConvertInt64(num, ready + readylen, possign);
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 20 ) { READY_FLUSH(); }
String::ConvertInt64(num, ready + readylen, possign);
readylen += chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case UNSIGNED | BIT64:
{
if ( READY_SIZE - readylen < 20 ) { READY_FLUSH(); }
uint64_t num = va_arg(parameters, uint64_t);
size_t chars = String::ConvertUInt64(num, ready + readylen);
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 20 ) { READY_FLUSH(); }
String::ConvertUInt64(num, ready + readylen);
readylen += chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case INTEGER | HEX:
case UNSIGNED | HEX:
{
if ( READY_SIZE - readylen < 8 ) { READY_FLUSH(); }
uint32_t num = va_arg(parameters, uint32_t);
size_t chars = String::ConvertUInt32Hex(num, ready + readylen);
size_t real_chars = chars;
if ( num && alternate ) chars += 2;
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 8 + 2 ) { READY_FLUSH(); }
if ( alternate && num )
ready[readylen++] = '0',
ready[readylen++] = 'x';
String::ConvertUInt32Hex(num, ready + readylen);
readylen += real_chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case INTEGER | BIT64 | HEX:
case UNSIGNED | BIT64 | HEX:
{
if ( READY_SIZE - readylen < 16 ) { READY_FLUSH(); }
uint64_t num = va_arg(parameters, uint64_t);
size_t chars = String::ConvertUInt64Hex(num, ready + readylen);
size_t real_chars = chars;
if ( num && alternate ) chars += 2;
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 16 + 2 ) { READY_FLUSH(); }
if ( alternate && num )
ready[readylen++] = '0',
ready[readylen++] = 'x';
String::ConvertUInt64Hex(num, ready + readylen);
readylen += real_chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case INTEGER | OCTAL:
case UNSIGNED | OCTAL:
{
if ( READY_SIZE - readylen < 20 ) { READY_FLUSH(); }
uint32_t num = va_arg(parameters, uint32_t);
size_t chars = String::ConvertUInt32Octal(num, ready + readylen);
size_t real_chars = chars;
if ( num && alternate ) chars += 1;
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 20 + 1 ) { READY_FLUSH(); }
if ( alternate && num )
ready[readylen++] = '0';
String::ConvertUInt32Octal(num, ready + readylen);
readylen += real_chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case INTEGER | BIT64 | OCTAL:
case UNSIGNED | BIT64 | OCTAL:
{
if ( READY_SIZE - readylen < 40 ) { READY_FLUSH(); }
uint64_t num = va_arg(parameters, uint64_t);
size_t chars = String::ConvertUInt64Octal(num, ready + readylen);
size_t real_chars = chars;
if ( num && alternate ) chars += 1;
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE - readylen < 40 + 1 ) { READY_FLUSH(); }
if ( alternate && num )
ready[readylen++] = '0';
String::ConvertUInt64Octal(num, ready + readylen);
readylen += real_chars;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
case STRING:
{
const char* str = va_arg(parameters, const char*);
size_t len = strlen(str);
size_t chars = len;
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
READY_FLUSH();
if ( callback && callback(user, str, len) != len ) { return SIZE_MAX; }
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
written += len;
break;
}
case CHARACTER:
{
int c = va_arg(parameters, int);
size_t len = 1;
size_t chars = len;
if ( prepend_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
if ( READY_SIZE <= readylen ) { READY_FLUSH(); }
ready[readylen++] = c;
if ( append_chars && chars < field_width ) { REPEAT_BLANKS(field_width - chars); }
break;
}
}
}
READY_FLUSH();
return written;
}

408
libc/stdio/vprintf_callback.cpp Normal file
View file

@ -0,0 +1,408 @@
/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013.
This file is part of the Sortix C Library.
The Sortix C Library is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
The Sortix C Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
stdio/vprintf_callback.cpp
Provides printf formatting functions that uses callbacks.
*******************************************************************************/
// Number of bugs seemingly unrelated bugs that have been traced to here:
// Countless + 2
#include <errno.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*, const char*, size_t amount)
{
return amount;
}
extern "C"
size_t vprintf_callback(size_t (*callback)(void*, const char*, size_t),
void* user,
const char* restrict format,
va_list parameters)
{
if ( !callback )
callback = noop_callback;
size_t written = 0;
bool rejected_bad_specifier = false;
while ( *format != '\0' )
{
if ( *format != '%' )
{
print_c:
size_t amount = 1;
while ( format[amount] && format[amount] != '%' )
amount++;
if ( callback(user, format, amount) != amount )
return SIZE_MAX;
format += 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;
(void) group_thousands;
(void) alternate_output_digits;
do 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;
} while ( false );
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 = (uintmax_t) va_arg(parameters, void*);
conversion = 'x';
alternate = !alternate;
}
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 : 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;
}
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;
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') )
prefix[prefix_length++] = '0',
prefix[prefix_length++] = conversion;
if ( alternate && conversion == 'o' && value != 0 )
prefix[prefix_length++] = '0';
char output[sizeof(uintmax_t) * 3];
size_t output_length = convert_integer(output, value, base, digits);
size_t output_length_with_precision =
precision != SIZE_MAX && output_length < precision ?
precision :
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;
char c;
if ( use_left_pad )
for ( size_t i = length_with_precision; i < abs_field_width; i++ )
if ( callback(user, &(c = ' '), 1) != 1 )
return SIZE_MAX;
else
written++;
if ( callback(user, prefix, prefix_length) != prefix_length )
return SIZE_MAX;
written += prefix_length;
if ( use_zero_pad )
for ( size_t i = normal_length; i < abs_field_width; i++ )
if ( callback(user, &(c = '0'), 1) != 1 )
return SIZE_MAX;
else
written++;
if ( use_precision )
for ( size_t i = normal_length; i < precision; i++ )
if ( callback(user, &(c = '0'), 1) != 1 )
return SIZE_MAX;
else
written++;
if ( callback(user, output, output_length) != output_length )
return SIZE_MAX;
written += output_length;
if ( use_right_pad )
for ( size_t i = length_with_precision; i < abs_field_width; i++ )
if ( callback(user, &(c = ' '), 1) != 1 )
return SIZE_MAX;
else
written++;
}
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;
}
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 ( callback(user, &c, 1) != 1 )
return SIZE_MAX;
written++;
}
else if ( *format == 's' && (format++, true) )
{
const char* string;
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;
size_t string_length = 0;
for ( size_t i = 0; i < precision && string[i]; i++ )
string_length++;
if ( callback(user, string, string_length) != string_length )
return SIZE_MAX;
written += string_length;
}
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;
}
return written;
}