This change adds missing features: * %[ for pattern matching with a scanset. * %m for allocation of strings. * %p for pointers. * Field width for integers. The following features remain unimplemented, like with printf(3): * Floating point support. * Wide character support. * %n$ positional parameters. The code has been completely refactored to be much more maintainable. The implemented features should now be standards compliant. A large number of edge cases have been fixed. The vscanf_callback(3) function has been renamed to vcbscanf(3) and a new cbscanf(3) function has been added.
470 lines
11 KiB
C
470 lines
11 KiB
C
/*
|
|
* Copyright (c) 2012, 2014, 2016, 2020 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/vcbscanf.c
|
|
* Input format conversion.
|
|
*/
|
|
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <limits.h>
|
|
#include <stdarg.h>
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
enum scan_type
|
|
{
|
|
TYPE_SHORT,
|
|
TYPE_SHORTSHORT,
|
|
TYPE_INT,
|
|
TYPE_LONG,
|
|
TYPE_LONGLONG,
|
|
TYPE_SIZE,
|
|
TYPE_PTRDIFF,
|
|
TYPE_MAX,
|
|
TYPE_PTR,
|
|
};
|
|
|
|
static int debase(unsigned char c, int base)
|
|
{
|
|
if ( c == '0' )
|
|
return 0;
|
|
int ret = -1;
|
|
if ( '0' <= c && c <= '9' ) { ret = c - '0' + 0; }
|
|
if ( 'a' <= c && c <= 'f' ) { ret = c - 'a' + 10; }
|
|
if ( 'A' <= c && c <= 'F' ) { ret = c - 'A' + 10; }
|
|
if ( base <= ret )
|
|
return -1;
|
|
return ret;
|
|
}
|
|
|
|
static size_t parse_scanset(bool scanset[256], const char* spec)
|
|
{
|
|
bool negate = spec[0] == '^';
|
|
size_t offset = negate ? 1 : 0;
|
|
for ( size_t i = 0; i < 256; i++ )
|
|
scanset[i] = negate;
|
|
if ( spec[offset] == ']' )
|
|
{
|
|
offset++;
|
|
scanset[(unsigned char) ']'] = !negate;
|
|
}
|
|
for ( ; spec[offset] && spec[offset] != ']'; offset++ )
|
|
{
|
|
unsigned char c = (unsigned char) spec[offset];
|
|
// Only allow ASCII in the scanset besides negation.
|
|
if ( 128 < c )
|
|
return offset;
|
|
if ( spec[offset + 1] == '-' &&
|
|
spec[offset + 2] &&
|
|
spec[offset + 2] != ']' )
|
|
{
|
|
unsigned char to = (unsigned char) spec[offset + 2];
|
|
for ( int i = c; i <= to; i++ )
|
|
scanset[i] = !negate;
|
|
offset += 2;
|
|
}
|
|
else
|
|
scanset[(unsigned char) spec[offset]] = !negate;
|
|
}
|
|
return offset;
|
|
}
|
|
|
|
int vcbscanf(void* fp,
|
|
int (*fgetc)(void*),
|
|
int (*ungetc)(int, void*),
|
|
const char* restrict format,
|
|
va_list ap)
|
|
{
|
|
int matched_items = 0;
|
|
uintmax_t bytes_parsed = 0;
|
|
int ic = 0;
|
|
while ( *format )
|
|
{
|
|
if ( isspace((unsigned char) *format) )
|
|
{
|
|
do format++;
|
|
while ( isspace((unsigned char) *format) );
|
|
while ( true )
|
|
{
|
|
ic = fgetc(fp);
|
|
if ( ic == EOF )
|
|
break;
|
|
bytes_parsed++;
|
|
if ( !isspace(ic) )
|
|
{
|
|
ungetc(ic, fp);
|
|
bytes_parsed--;
|
|
break;
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
else if ( format[0] != '%' || format[1] == '%' )
|
|
{
|
|
if ( *format == '%' )
|
|
format++;
|
|
unsigned char c = *format++;
|
|
ic = fgetc(fp);
|
|
if ( ic == EOF )
|
|
return matched_items ? matched_items : EOF;
|
|
bytes_parsed++;
|
|
if ( ic != c )
|
|
{
|
|
ungetc(ic, fp);
|
|
bytes_parsed--;
|
|
break;
|
|
}
|
|
continue;
|
|
}
|
|
format++;
|
|
bool discard = format[0] == '*';
|
|
if ( discard )
|
|
format++;
|
|
size_t field_width = 0;
|
|
while ( '0'<= *format && *format <= '9' )
|
|
field_width = field_width * 10 + *format++ - '0';
|
|
bool allocate = false;
|
|
if ( *format == 'm' )
|
|
{
|
|
allocate = true;
|
|
format++;
|
|
}
|
|
enum scan_type scan_type = TYPE_INT;
|
|
switch ( *format++ )
|
|
{
|
|
case 'h':
|
|
scan_type = *format == 'h' ?
|
|
(format++, TYPE_SHORTSHORT) :
|
|
TYPE_SHORT;
|
|
break;
|
|
case 'j': scan_type = TYPE_MAX; break;
|
|
case 'l':
|
|
scan_type = *format == 'l' ?
|
|
(format++, TYPE_LONGLONG) :
|
|
TYPE_LONG;
|
|
break;
|
|
case 'L': scan_type = TYPE_LONGLONG; break;
|
|
case 't': scan_type = TYPE_PTRDIFF; break;
|
|
case 'z': scan_type = TYPE_SIZE; break;
|
|
default: format--;
|
|
}
|
|
if ( *format == 'd' || *format == 'i' || *format == 'o' ||
|
|
*format == 'u' || *format == 'x' || *format == 'X' ||
|
|
*format == 'p' )
|
|
{
|
|
int base;
|
|
bool is_unsigned;
|
|
switch ( *format++ )
|
|
{
|
|
case 'd': base = 10; is_unsigned = false; break;
|
|
case 'i': base = 0; is_unsigned = false; break;
|
|
case 'o': base = 8; is_unsigned = true; break;
|
|
case 'u': base = 10; is_unsigned = true; break;
|
|
case 'p':
|
|
if ( scan_type != TYPE_INT )
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
scan_type = TYPE_PTR;
|
|
case 'X':
|
|
case 'x': base = 16; is_unsigned = true; break;
|
|
default: __builtin_unreachable();
|
|
}
|
|
if ( allocate )
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
bool parsed_int = false;
|
|
uintmax_t int_value = 0;
|
|
bool negative = false;
|
|
bool has_prefix = false;
|
|
bool maybe_base16 = false;
|
|
if ( !field_width )
|
|
field_width = SIZE_MAX;
|
|
size_t i = 0;
|
|
for ( ; i < field_width; i++ )
|
|
{
|
|
ic = fgetc(fp);
|
|
if ( ic == EOF )
|
|
break;
|
|
bytes_parsed++;
|
|
if ( i == 0 && isspace(ic) )
|
|
{
|
|
i--;
|
|
continue;
|
|
}
|
|
if ( ic == '-' && i == 0 && !has_prefix )
|
|
{
|
|
negative = true;
|
|
has_prefix = true;
|
|
}
|
|
else if ( ic == '+' && i == 0 && !has_prefix )
|
|
{
|
|
negative = false;
|
|
has_prefix = true;
|
|
}
|
|
else if ( (ic == 'x' || ic == 'X') &&
|
|
(base == 0 || base == 16) &&
|
|
(has_prefix ? i == 2 : i == 1) &&
|
|
int_value == 0 )
|
|
{
|
|
maybe_base16 = true;
|
|
parsed_int = false;
|
|
}
|
|
else if ( ic == '0' && (has_prefix ? i == 1 : i == 0) )
|
|
{
|
|
int_value = 0;
|
|
parsed_int = true;
|
|
}
|
|
else
|
|
{
|
|
if ( base == 0 )
|
|
{
|
|
if ( maybe_base16 )
|
|
{
|
|
if ( debase(ic, 16) < 0 )
|
|
{
|
|
ungetc(ic, fp);
|
|
bytes_parsed--;
|
|
break;
|
|
}
|
|
base = 16;
|
|
}
|
|
else if ( parsed_int )
|
|
base = 8;
|
|
else
|
|
base = 10;
|
|
}
|
|
int cval = debase(ic, base);
|
|
if ( cval < 0 )
|
|
{
|
|
ungetc(ic, fp);
|
|
bytes_parsed--;
|
|
break;
|
|
}
|
|
if ( __builtin_mul_overflow(int_value, base, &int_value) )
|
|
int_value = UINTMAX_MAX;
|
|
if ( __builtin_add_overflow(int_value, cval, &int_value) )
|
|
int_value = UINTMAX_MAX;
|
|
parsed_int = true;
|
|
}
|
|
}
|
|
if ( !parsed_int )
|
|
return matched_items || i || ic != EOF ? matched_items : EOF;
|
|
if ( discard )
|
|
continue;
|
|
uintmax_t uintmaxval = int_value;
|
|
if ( negative )
|
|
uintmaxval = -uintmaxval;
|
|
intmax_t intmaxval = uintmaxval;
|
|
bool un = is_unsigned;
|
|
switch ( scan_type )
|
|
{
|
|
case TYPE_SHORTSHORT:
|
|
if ( un ) *va_arg(ap, unsigned char*) = uintmaxval;
|
|
else *va_arg(ap, signed char*) = intmaxval;
|
|
break;
|
|
case TYPE_SHORT:
|
|
if ( un ) *va_arg(ap, unsigned short*) = uintmaxval;
|
|
else *va_arg(ap, signed short*) = intmaxval;
|
|
break;
|
|
case TYPE_INT:
|
|
if ( un ) *va_arg(ap, unsigned int*) = uintmaxval;
|
|
else *va_arg(ap, signed int*) = intmaxval;
|
|
break;
|
|
case TYPE_LONG:
|
|
if ( un ) *va_arg(ap, unsigned long*) = uintmaxval;
|
|
else *va_arg(ap, signed long*) = intmaxval;
|
|
break;
|
|
case TYPE_LONGLONG:
|
|
if ( un ) *va_arg(ap, unsigned long long*) = uintmaxval;
|
|
else *va_arg(ap, signed long long*) = intmaxval;
|
|
break;
|
|
case TYPE_PTRDIFF:
|
|
*va_arg(ap, ptrdiff_t*) = intmaxval;
|
|
break;
|
|
case TYPE_SIZE:
|
|
if ( un ) *va_arg(ap, size_t*) = uintmaxval;
|
|
else *va_arg(ap, ssize_t*) = intmaxval;
|
|
break;
|
|
case TYPE_MAX:
|
|
if ( un ) *va_arg(ap, uintmax_t*) = uintmaxval;
|
|
else *va_arg(ap, intmax_t*) = intmaxval;
|
|
break;
|
|
case TYPE_PTR:
|
|
*va_arg(ap, void**) = (void*) (uintptr_t) uintmaxval;
|
|
break;
|
|
}
|
|
matched_items++;
|
|
}
|
|
else if ( *format == 's' || *format == '[' || *format == 'c' ||
|
|
*format == 'C' || *format == 'S' )
|
|
{
|
|
bool scanset[256];
|
|
bool string;
|
|
bool use_scanset;
|
|
switch ( *format++ )
|
|
{
|
|
case 'S':
|
|
if ( scan_type != TYPE_INT )
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
scan_type = TYPE_LONG;
|
|
case 's': string = true; use_scanset = false; break;
|
|
case '[': string = true; use_scanset = true; break;
|
|
case 'C':
|
|
if ( scan_type != TYPE_INT )
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
scan_type = TYPE_LONG;
|
|
case 'c': string = false; use_scanset = false; break;
|
|
default: __builtin_unreachable();
|
|
}
|
|
if ( use_scanset )
|
|
{
|
|
size_t offset = parse_scanset(scanset, format);
|
|
if ( format[offset] != ']' )
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
format += offset + 1;
|
|
}
|
|
if ( scan_type != TYPE_INT )
|
|
{
|
|
#ifndef __is_sortix_libk
|
|
fprintf(stderr,
|
|
"%s:%u: error: scanf does not support wide strings\n",
|
|
__FILE__, __LINE__);
|
|
#endif
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
}
|
|
if ( !field_width )
|
|
field_width = string ? SIZE_MAX : 1;
|
|
char** strptr = NULL;
|
|
char* str = NULL;
|
|
size_t strsize = 0;
|
|
if ( !discard )
|
|
{
|
|
if ( allocate )
|
|
{
|
|
strptr = va_arg(ap, char**);
|
|
strsize = 16;
|
|
str = (char*) malloc(strsize);
|
|
if ( !str )
|
|
return matched_items ? matched_items : EOF;
|
|
}
|
|
else
|
|
str = va_arg(ap, char*);
|
|
}
|
|
size_t i = 0;
|
|
while ( i < field_width )
|
|
{
|
|
ic = fgetc(fp);
|
|
if ( ic == EOF )
|
|
break;
|
|
bytes_parsed++;
|
|
if ( string && (use_scanset ? !scanset[ic] : isspace(ic)) )
|
|
{
|
|
if ( !use_scanset && !i )
|
|
continue;
|
|
ungetc(ic, fp);
|
|
bytes_parsed--;
|
|
break;
|
|
}
|
|
if ( !discard )
|
|
{
|
|
if ( allocate && i + string == strsize )
|
|
{
|
|
char* newstr = (char*) reallocarray(str, strsize, 2);
|
|
if ( !newstr )
|
|
{
|
|
free(str);
|
|
return matched_items ? matched_items : EOF;
|
|
}
|
|
str = newstr;
|
|
strsize *= 2;
|
|
}
|
|
str[i++] = (char) ic;
|
|
}
|
|
else
|
|
i++;
|
|
}
|
|
if ( string ? !i : i < field_width )
|
|
{
|
|
if ( !discard && allocate )
|
|
free(str);
|
|
return matched_items || i || ic != EOF ? matched_items : EOF;
|
|
}
|
|
if ( !discard )
|
|
{
|
|
if ( string )
|
|
str[i] = '\0';
|
|
if ( allocate )
|
|
{
|
|
char* newstr = realloc(str, i + string);
|
|
str = newstr ? newstr : str;
|
|
*strptr = str;
|
|
}
|
|
if ( string || i == field_width )
|
|
matched_items++;
|
|
}
|
|
}
|
|
else if ( *format == 'n' )
|
|
{
|
|
format++;
|
|
if ( allocate )
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
switch ( scan_type )
|
|
{
|
|
case TYPE_SHORTSHORT:
|
|
*va_arg(ap, signed char*) = bytes_parsed;
|
|
break;
|
|
case TYPE_SHORT:
|
|
*va_arg(ap, signed short*) = bytes_parsed;
|
|
break;
|
|
case TYPE_INT:
|
|
*va_arg(ap, signed int*) = bytes_parsed;
|
|
break;
|
|
case TYPE_LONG:
|
|
*va_arg(ap, signed long*) = bytes_parsed;
|
|
break;
|
|
case TYPE_LONGLONG:
|
|
*va_arg(ap, signed long long*) = bytes_parsed;
|
|
break;
|
|
case TYPE_PTRDIFF:
|
|
*va_arg(ap, ptrdiff_t*) = bytes_parsed;
|
|
break;
|
|
case TYPE_SIZE:
|
|
*va_arg(ap, ssize_t*) = bytes_parsed;
|
|
break;
|
|
case TYPE_MAX:
|
|
*va_arg(ap, intmax_t*) = bytes_parsed;
|
|
break;
|
|
case TYPE_PTR: __builtin_unreachable();
|
|
}
|
|
}
|
|
else if ( *format == 'a' || *format == 'A' ||
|
|
*format == 'e' || *format == 'E' ||
|
|
*format == 'f' || *format == 'F' ||
|
|
*format == 'g' || *format == 'G' )
|
|
{
|
|
#ifndef __is_sortix_libk
|
|
fprintf(stderr, "%s:%u: error: scanf does not support \"%%%c\")\n",
|
|
__FILE__, __LINE__, *format);
|
|
#endif
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
}
|
|
else
|
|
return errno = EINVAL, matched_items ? matched_items : EOF;
|
|
}
|
|
return matched_items;
|
|
}
|