X-Git-Url: https://pd.if.org/git/?p=pdclib;a=blobdiff_plain;f=functions%2F_PDCLIB%2Fscan.c;h=1502f62ba5cc6c489fcc2e94b046cfbefea6987e;hp=d12e8844a06e9eebc712cc68f522a5afbdc026e0;hb=5bcc00c1b85feff1996e3f34a1a9ebf3b624161e;hpb=68525aefa7b7b1f2f769e287e1f2f3a4585005ff diff --git a/functions/_PDCLIB/scan.c b/functions/_PDCLIB/scan.c index d12e884..1502f62 100644 --- a/functions/_PDCLIB/scan.c +++ b/functions/_PDCLIB/scan.c @@ -7,10 +7,195 @@ */ #include +#include +#include +#include + +/* 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 + + +static bool MATCH( const char x, struct _PDCLIB_status_t * status ) +{ + if ( status->stream != NULL ) + { + /* Matching against stream */ + if ( status->stream->buffer[ status->stream->bufidx ] == x ) + { + getc( status->stream ); + ++(status->i); + return true; + } + else + { + return false; + } + } + else + { + /* Matching against string */ + if ( *(status->s) == x ) + { + ++(status->s); + ++(status->i); + return true; + } + else + { + return false; + } + } +} + const char * _PDCLIB_scan( const char * spec, struct _PDCLIB_status_t * status ) { - return ++spec; + const char * orig_spec = spec; + if ( *(++spec) == '%' ) + { + /* %% -> match single '%' */ + MATCH( *spec, status ); + return ++spec; + } + /* Initializing status structure */ + status->flags = 0; + status->base = 0; + status->this = 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. + */ + status->width = (int)strtol( spec, (char**)&spec, 10 ); + + /* 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 */ + 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': + /* TODO */ + break; + case 's': + /* TODO */ + break; + case 'p': + /* TODO */ + status->base = 16; + status->flags |= E_unsigned; + break; + case 'n': + { + int * val = va_arg( status->arg, int * ); + *val = status->i; + return ++spec; + } + default: + /* No conversion specifier. Bad conversion. */ + return orig_spec; + } + /* TODO: Actual conversions */ + return NULL; } #ifdef TEST