+++ /dev/null
-/* $Id$ */
-
-/* _PDCLIB_scan( const char *, struct _PDCLIB_status_t * )
-
- This file is part of the Public Domain C Library (PDCLib).
- Permission is granted to use, modify, and / or redistribute at will.
-*/
-
-#include <stdio.h>
-#include <stdbool.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <ctype.h>
-#include <string.h>
-#include <stddef.h>
-#include <limits.h>
-
-#ifndef REGTEST
-
-/* Using an integer's bits as flags for both the conversion flags and length
- modifiers.
-*/
-#define E_suppressed 1<<0
-#define E_char 1<<6
-#define E_short 1<<7
-#define E_long 1<<8
-#define E_llong 1<<9
-#define E_intmax 1<<10
-#define E_size 1<<11
-#define E_ptrdiff 1<<12
-#define E_intptr 1<<13
-#define E_ldouble 1<<14
-#define E_unsigned 1<<16
-
-
-/* Helper function to get a character from the string or stream, whatever is
- used for input. When reading from a string, returns EOF on end-of-string
- so that handling of the return value can be uniform for both streams and
- strings.
-*/
-static int GET( struct _PDCLIB_status_t * status )
-{
- int rc = EOF;
- if ( status->stream != NULL )
- {
- rc = getc( status->stream );
- }
- else
- {
- rc = ( *status->s == '\0' ) ? EOF : (unsigned char)*((status->s)++);
- }
- if ( rc != EOF )
- {
- ++(status->i);
- ++(status->current);
- }
- return rc;
-}
-
-
-/* Helper function to put a read character back into the string or stream,
- whatever is used for input.
-*/
-static void UNGET( int c, struct _PDCLIB_status_t * status )
-{
- if ( status->stream != NULL )
- {
- ungetc( c, status->stream ); /* TODO: Error? */
- }
- else
- {
- --(status->s);
- }
- --(status->i);
- --(status->current);
-}
-
-
-/* Helper function to check if a character is part of a given scanset */
-static bool IN_SCANSET( const char * scanlist, const char * end_scanlist, int rc )
-{
- // SOLAR
- int previous = -1;
- while ( scanlist != end_scanlist )
- {
- if ( ( *scanlist == '-' ) && ( previous != -1 ) )
- {
- /* possible scangroup ("a-z") */
- if ( ++scanlist == end_scanlist )
- {
- /* '-' at end of scanlist does not describe a scangroup */
- return rc == '-';
- }
- while ( ++previous <= (unsigned char)*scanlist )
- {
- if ( previous == rc )
- {
- return true;
- }
- }
- previous = -1;
- }
- else
- {
- /* not a scangroup, check verbatim */
- if ( rc == (unsigned char)*scanlist )
- {
- return true;
- }
- previous = (unsigned char)(*scanlist++);
- }
- }
- return false;
-}
-
-
-const char * _PDCLIB_scan( const char * spec, struct _PDCLIB_status_t * status )
-{
- /* generic input character */
- int rc;
- const char * orig_spec = spec;
- if ( *(++spec) == '%' )
- {
- /* %% -> match single '%' */
- rc = GET( status );
- switch ( rc )
- {
- case EOF:
- /* input error */
- if ( status->n == 0 )
- {
- status->n = -1;
- }
- return NULL;
- case '%':
- return ++spec;
- default:
- UNGET( rc, status );
- break;
- }
- }
- /* Initializing status structure */
- status->flags = 0;
- status->base = -1;
- status->current = 0;
- status->width = 0;
- status->prec = 0;
-
- /* '*' suppresses assigning parsed value to variable */
- if ( *spec == '*' )
- {
- status->flags |= E_suppressed;
- ++spec;
- }
-
- /* If a width is given, strtol() will return its value. If not given,
- strtol() will return zero. In both cases, endptr will point to the
- rest of the conversion specifier - just what we need.
- */
- char const * prev_spec = spec;
- status->width = (int)strtol( spec, (char**)&spec, 10 );
- if ( spec == prev_spec )
- {
- status->width = UINT_MAX;
- }
-
- /* Optional length modifier
- We step one character ahead in any case, and step back only if we find
- there has been no length modifier (or step ahead another character if it
- has been "hh" or "ll").
- */
- switch ( *(spec++) )
- {
- case 'h':
- if ( *spec == 'h' )
- {
- /* hh -> char */
- status->flags |= E_char;
- ++spec;
- }
- else
- {
- /* h -> short */
- status->flags |= E_short;
- }
- break;
- case 'l':
- if ( *spec == 'l' )
- {
- /* ll -> long long */
- status->flags |= E_llong;
- ++spec;
- }
- else
- {
- /* l -> long */
- status->flags |= E_long;
- }
- break;
- case 'j':
- /* j -> intmax_t, which might or might not be long long */
- status->flags |= E_intmax;
- break;
- case 'z':
- /* z -> size_t, which might or might not be unsigned int */
- status->flags |= E_size;
- break;
- case 't':
- /* t -> ptrdiff_t, which might or might not be long */
- status->flags |= E_ptrdiff;
- break;
- case 'L':
- /* L -> long double */
- status->flags |= E_ldouble;
- break;
- default:
- --spec;
- break;
- }
-
- /* Conversion specifier */
-
- /* whether valid input had been parsed */
- bool value_parsed = false;
-
- switch ( *spec )
- {
- case 'd':
- status->base = 10;
- break;
- case 'i':
- status->base = 0;
- break;
- case 'o':
- status->base = 8;
- status->flags |= E_unsigned;
- break;
- case 'u':
- status->base = 10;
- status->flags |= E_unsigned;
- break;
- case 'x':
- status->base = 16;
- status->flags |= E_unsigned;
- break;
- case 'f':
- case 'F':
- case 'e':
- case 'E':
- case 'g':
- case 'G':
- case 'a':
- case 'A':
- break;
- case 'c':
- {
- char * c = va_arg( status->arg, char * );
- /* for %c, default width is one */
- if ( status->width == SIZE_MAX )
- {
- status->width = 1;
- }
- /* reading until width reached or input exhausted */
- while ( ( status->current < status->width ) &&
- ( ( rc = GET( status ) ) != EOF ) )
- {
- *(c++) = rc;
- value_parsed = true;
- }
- /* width or input exhausted */
- if ( value_parsed )
- {
- ++status->n;
- return ++spec;
- }
- else
- {
- /* input error, no character read */
- if ( status->n == 0 )
- {
- status->n = -1;
- }
- return NULL;
- }
- }
- case 's':
- {
- char * c = va_arg( status->arg, char * );
- while ( ( status->current < status->width ) &&
- ( ( rc = GET( status ) ) != EOF ) )
- {
- if ( isspace( rc ) )
- {
- UNGET( rc, status );
- if ( value_parsed )
- {
- /* matching sequence terminated by whitespace */
- *c = '\0';
- ++status->n;
- return ++spec;
- }
- else
- {
- /* matching error */
- return NULL;
- }
- }
- else
- {
- /* match */
- value_parsed = true;
- *(c++) = rc;
- }
- }
- /* width or input exhausted */
- if ( value_parsed )
- {
- *c = '\0';
- ++status->n;
- return ++spec;
- }
- else
- {
- /* input error, no character read */
- if ( status->n == 0 )
- {
- status->n = -1;
- }
- return NULL;
- }
- }
- case '[':
- {
- const char * endspec = spec;
- bool negative_scanlist = false;
- if ( *(++endspec) == '^' )
- {
- negative_scanlist = true;
- ++endspec;
- }
- spec = endspec;
- do
- {
- // TODO: This can run beyond a malformed format string
- ++endspec;
- } while ( *endspec != ']' );
- // read according to scanlist, equiv. to %s above
- char * c = va_arg( status->arg, char * );
- while ( ( status->current < status->width ) &&
- ( ( rc = GET( status ) ) != EOF ) )
- {
- if ( negative_scanlist )
- {
- if ( IN_SCANSET( spec, endspec, rc ) )
- {
- UNGET( rc, status );
- break;
- }
- }
- else
- {
- if ( ! IN_SCANSET( spec, endspec, rc ) )
- {
- UNGET( rc, status );
- break;
- }
- }
- value_parsed = true;
- *(c++) = rc;
- }
- if ( value_parsed )
- {
- *c = '\0';
- ++status->n;
- return ++endspec;
- }
- else
- {
- if ( rc == EOF )
- {
- status->n = -1;
- }
- return NULL;
- }
- }
- case 'p':
- status->base = 16;
- // TODO: Like _PDCLIB_print, E_pointer(?)
- status->flags |= E_unsigned | E_long;
- break;
- case 'n':
- {
- int * val = va_arg( status->arg, int * );
- *val = status->i;
- return ++spec;
- }
- default:
- /* No conversion specifier. Bad conversion. */
- return orig_spec;
- }
-
- if ( status->base != -1 )
- {
- /* integer conversion */
- uintmax_t value = 0; /* absolute value read */
- bool prefix_parsed = false;
- int sign = 0;
- while ( ( status->current < status->width ) &&
- ( ( rc = GET( status ) ) != EOF ) )
- {
- if ( isspace( rc ) )
- {
- if ( sign )
- {
- /* matching sequence terminated by whitespace */
- UNGET( rc, status );
- break;
- }
- else
- {
- /* leading whitespace not counted against width */
- status->current--;
- }
- }
- else if ( ! sign )
- {
- /* no sign parsed yet */
- switch ( rc )
- {
- case '-':
- sign = -1;
- break;
- case '+':
- sign = 1;
- break;
- default:
- /* not a sign; put back character */
- sign = 1;
- UNGET( rc, status );
- break;
- }
- }
- else if ( ! prefix_parsed )
- {
- /* no prefix (0x... for hex, 0... for octal) parsed yet */
- prefix_parsed = true;
- if ( rc != '0' )
- {
- /* not a prefix; if base not yet set, set to decimal */
- if ( status->base == 0 )
- {
- status->base = 10;
- }
- UNGET( rc, status );
- }
- else
- {
- /* starts with zero, so it might be a prefix. */
- /* check what follows next (might be 0x...) */
- if ( ( status->current < status->width ) &&
- ( ( rc = GET( status ) ) != EOF ) )
- {
- if ( tolower( rc ) == 'x' )
- {
- /* 0x... would be prefix for hex base... */
- if ( ( status->base == 0 ) ||
- ( status->base == 16 ) )
- {
- status->base = 16;
- }
- else
- {
- /* ...unless already set to other value */
- UNGET( rc, status );
- value_parsed = true;
- }
- }
- else
- {
- /* 0... but not 0x.... would be octal prefix */
- UNGET( rc, status );
- if ( status->base == 0 )
- {
- status->base = 8;
- }
- /* in any case we have read a zero */
- value_parsed = true;
- }
- }
- else
- {
- /* failed to read beyond the initial zero */
- value_parsed = true;
- break;
- }
- }
- }
- else
- {
- char * digitptr = memchr( _PDCLIB_digits, tolower( rc ), status->base );
- if ( digitptr == NULL )
- {
- /* end of input item */
- UNGET( rc, status );
- break;
- }
- value *= status->base;
- value += digitptr - _PDCLIB_digits;
- value_parsed = true;
- }
- }
- /* width or input exhausted, or non-matching character */
- if ( ! value_parsed )
- {
- /* out of input before anything could be parsed - input error */
- /* FIXME: if first character does not match, value_parsed is not set - but it is NOT an input error */
- if ( ( status->n == 0 ) && ( rc == EOF ) )
- {
- status->n = -1;
- }
- return NULL;
- }
- /* convert value to target type and assign to parameter */
- if ( ! ( status->flags & E_suppressed ) )
- {
- switch ( status->flags & ( E_char | E_short | E_long | E_llong |
- E_intmax | E_size | E_ptrdiff |
- E_unsigned ) )
- {
- case E_char:
- *( va_arg( status->arg, char * ) ) = (char)( value * sign );
- break;
- case E_char | E_unsigned:
- *( va_arg( status->arg, unsigned char * ) ) = (unsigned char)( value * sign );
- break;
-
- case E_short:
- *( va_arg( status->arg, short * ) ) = (short)( value * sign );
- break;
- case E_short | E_unsigned:
- *( va_arg( status->arg, unsigned short * ) ) = (unsigned short)( value * sign );
- break;
-
- case 0:
- *( va_arg( status->arg, int * ) ) = (int)( value * sign );
- break;
- case E_unsigned:
- *( va_arg( status->arg, unsigned int * ) ) = (unsigned int)( value * sign );
- break;
-
- case E_long:
- *( va_arg( status->arg, long * ) ) = (long)( value * sign );
- break;
- case E_long | E_unsigned:
- *( va_arg( status->arg, unsigned long * ) ) = (unsigned long)( value * sign );
- break;
-
- case E_llong:
- *( va_arg( status->arg, long long * ) ) = (long long)( value * sign );
- break;
- case E_llong | E_unsigned:
- *( va_arg( status->arg, unsigned long long * ) ) = (unsigned long long)( value * sign );
- break;
-
- case E_intmax:
- *( va_arg( status->arg, intmax_t * ) ) = (intmax_t)( value * sign );
- break;
- case E_intmax | E_unsigned:
- *( va_arg( status->arg, uintmax_t * ) ) = (uintmax_t)( value * sign );
- break;
-
- case E_size:
- /* E_size always implies unsigned */
- *( va_arg( status->arg, size_t * ) ) = (size_t)( value * sign );
- break;
-
- case E_ptrdiff:
- /* E_ptrdiff always implies signed */
- *( va_arg( status->arg, ptrdiff_t * ) ) = (ptrdiff_t)( value * sign );
- break;
-
- default:
- puts( "UNSUPPORTED SCANF FLAG COMBINATION" );
- return NULL; /* behaviour unspecified */
- }
- ++(status->n);
- }
- return ++spec;
- }
- /* TODO: Floats. */
- return NULL;
-}
-#endif
-
-#ifdef TEST
-#define _PDCLIB_FILEID "_PDCLIB/scan.c"
-#define _PDCLIB_STRINGIO
-
-#include <_PDCLIB_test.h>
-
-#ifndef REGTEST
-static int testscanf( char const * s, char const * format, ... )
-{
- struct _PDCLIB_status_t status;
- status.n = 0;
- status.i = 0;
- status.s = (char *)s;
- status.stream = NULL;
- va_start( status.arg, format );
- if ( *(_PDCLIB_scan( format, &status )) != '\0' )
- {
- printf( "_PDCLIB_scan() did not return end-of-specifier on '%s'.\n", format );
- ++TEST_RESULTS;
- }
- va_end( status.arg );
- return status.n;
-}
-#endif
-
-#define TEST_CONVERSION_ONLY
-
-int main( void )
-{
-#ifndef REGTEST
- char source[100];
-#include "scanf_testcases.h"
-#endif
- return TEST_RESULTS;
-}
-
-#endif
projects / pdclib.old / blobdiff