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Diffstat (limited to 'src/pdclib/functions/_PDCLIB/_PDCLIB_print.c')
| -rw-r--r-- | src/pdclib/functions/_PDCLIB/_PDCLIB_print.c | 625 |
1 files changed, 625 insertions, 0 deletions
diff --git a/src/pdclib/functions/_PDCLIB/_PDCLIB_print.c b/src/pdclib/functions/_PDCLIB/_PDCLIB_print.c new file mode 100644 index 0000000..3c13da2 --- /dev/null +++ b/src/pdclib/functions/_PDCLIB/_PDCLIB_print.c @@ -0,0 +1,625 @@ +/* _PDCLIB_print( 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 <stdint.h> +#include <stdarg.h> +#include <stdlib.h> +#include <stddef.h> +#include <string.h> + +#ifndef REGTEST + +/* Using an integer's bits as flags for both the conversion flags and length + modifiers. +*/ +/* FIXME: one too many flags to work on a 16-bit machine, join some (e.g. the + width flags) into a combined field. +*/ +#define E_minus (1<<0) +#define E_plus (1<<1) +#define E_alt (1<<2) +#define E_space (1<<3) +#define E_zero (1<<4) +#define E_done (1<<5) + +#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_pointer (1<<13) + +#define E_ldouble (1<<14) + +#define E_lower (1<<15) +#define E_unsigned (1<<16) + +/* This macro delivers a given character to either a memory buffer or a stream, + depending on the contents of 'status' (struct _PDCLIB_status_t). + x - the character to be delivered + i - pointer to number of characters already delivered in this call + n - pointer to maximum number of characters to be delivered in this call + s - the buffer into which the character shall be delivered +*/ +#define PUT( x ) \ +do { \ + int character = x; \ + if ( status->i < status->n ) { \ + if ( status->stream != NULL ) \ + putc( character, status->stream ); \ + else \ + status->s[status->i] = character; \ + } \ + ++(status->i); \ +} while ( 0 ) + + +static void intformat( intmax_t value, struct _PDCLIB_status_t * status ) +{ + /* At worst, we need two prefix characters (hex prefix). */ + char preface[3] = "\0"; + size_t preidx = 0; + if ( status->prec < 0 ) + { + status->prec = 1; + } + if ( ( status->flags & E_alt ) && ( status->base == 16 || status->base == 8 ) && ( value != 0 ) ) + { + /* Octal / hexadecimal prefix for "%#" conversions */ + preface[ preidx++ ] = '0'; + if ( status->base == 16 ) + { + preface[ preidx++ ] = ( status->flags & E_lower ) ? 'x' : 'X'; + } + } + if ( value < 0 ) + { + /* Negative sign for negative values - at all times. */ + preface[ preidx++ ] = '-'; + } + else if ( ! ( status->flags & E_unsigned ) ) + { + /* plus sign / extra space are only for unsigned conversions */ + if ( status->flags & E_plus ) + { + preface[ preidx++ ] = '+'; + } + else if ( status->flags & E_space ) + { + preface[ preidx++ ] = ' '; + } + } + { + /* At this point, status->current has the number of digits queued up. + Determine if we have a precision requirement to pad those. + */ + size_t prec_pads = ( (_PDCLIB_size_t)status->prec > status->current ) ? ( (_PDCLIB_size_t)status->prec - status->current ) : 0; + if ( ! ( status->flags & ( E_minus | E_zero ) ) ) + { + /* Space padding is only done if no zero padding or left alignment + is requested. Calculate the number of characters that WILL be + printed, including any prefixes determined above. + */ + /* The number of characters to be printed, plus prefixes if any. */ + /* This line contained probably the most stupid, time-wasting bug + I've ever perpetrated. Greetings to Samface, DevL, and all + sceners at Breakpoint 2006. + */ + size_t characters = preidx + ( ( status->current > (_PDCLIB_size_t)status->prec ) ? status->current : (_PDCLIB_size_t)status->prec ); + if ( status->width > characters ) + { + size_t i; + for ( i = 0; i < status->width - characters; ++i ) + { + PUT( ' ' ); + ++(status->current); + } + } + } + /* Now we did the padding, do the prefixes (if any). */ + preidx = 0; + while ( preface[ preidx ] != '\0' ) + { + PUT( preface[ preidx++ ] ); + ++(status->current); + } + /* Do the precision padding if necessary. */ + while ( prec_pads-- > 0 ) + { + PUT( '0' ); + ++(status->current); + } + if ( ( ! ( status->flags & E_minus ) ) && ( status->flags & E_zero ) ) + { + /* If field is not left aligned, and zero padding is requested, do + so. + */ + while ( status->current < status->width ) + { + PUT( '0' ); + ++(status->current); + } + } + } +} + + +/* This function recursively converts a given integer value to a character + stream. The conversion is done under the control of a given status struct + and written either to a character string or a stream, depending on that + same status struct. The status struct also keeps the function from exceeding + snprintf() limits, and enables any necessary padding / prefixing of the + output once the number of characters to be printed is known, which happens + at the lowermost recursion level. +*/ +#define INT2BASE() \ +do \ +{ \ + /* Special case: zero value, zero precision -- no output (but padding) */ \ + if ( status->current == 0 && value == 0 && status->prec == 0 ) \ + { \ + intformat( value, status ); \ + } \ + else \ + { \ + /* Registering the character being printed at the end of the function here \ + already so it will be taken into account when the deepestmost recursion \ + does the prefix / padding stuff. \ + */ \ + ++(status->current); \ + if ( ( value / status->base ) != 0 ) \ + { \ + /* More digits to be done - recurse deeper */ \ + int2base( value / status->base, status ); \ + } \ + else \ + { \ + /* We reached the last digit, the deepest point of our recursion, and \ + only now know how long the number to be printed actually is. Now we \ + have to do the sign, prefix, width, and precision padding stuff \ + before printing the numbers while we resurface from the recursion. \ + */ \ + intformat( value, status ); \ + } \ + /* Recursion tail - print the current digit. */ \ + { \ + int digit = value % status->base; \ + if ( digit < 0 ) \ + { \ + digit *= -1; \ + } \ + if ( status->flags & E_lower ) \ + { \ + /* Lowercase letters. Same array used for strto...(). */ \ + PUT( _PDCLIB_digits[ digit ] ); \ + } \ + else \ + { \ + /* Uppercase letters. Array only used here, only 0-F. */ \ + PUT( _PDCLIB_Xdigits[ digit ] ); \ + } \ + } \ + } \ +} while ( 0 ) + + +static void int2base( intmax_t value, struct _PDCLIB_status_t * status ) +{ + INT2BASE(); +} + + +static void stringformat( const char * s, struct _PDCLIB_status_t * status ) +{ + if ( status->flags & E_char ) + { + status->prec = 1; + } + else + { + if ( status->prec < 0 ) + { + status->prec = strlen( s ); + } + else + { + int i; + for ( i = 0; i < status->prec; ++i ) + { + if ( s[i] == 0 ) + { + status->prec = i; + break; + } + } + } + } + if ( ! ( status->flags & E_minus ) && ( status->width > (_PDCLIB_size_t)status->prec ) ) + { + while ( status->current < ( status->width - status->prec ) ) + { + PUT( ' ' ); + ++(status->current); + } + } + while ( status->prec > 0 ) + { + PUT( *(s++) ); + --(status->prec); + ++(status->current); + } + if ( status->flags & E_minus ) + { + while ( status->width > status->current ) + { + PUT( ' ' ); + ++(status->current); + } + } +} + + +const char * _PDCLIB_print( const char * spec, struct _PDCLIB_status_t * status ) +{ + const char * orig_spec = spec; + if ( *(++spec) == '%' ) + { + /* %% -> print single '%' */ + PUT( *spec ); + return ++spec; + } + /* Initializing status structure */ + status->flags = 0; + status->base = 0; + status->current = 0; + status->width = 0; + status->prec = EOF; + + /* First come 0..n flags */ + do + { + switch ( *spec ) + { + case '-': + /* left-aligned output */ + status->flags |= E_minus; + ++spec; + break; + case '+': + /* positive numbers prefixed with '+' */ + status->flags |= E_plus; + ++spec; + break; + case '#': + /* alternative format (leading 0x for hex, 0 for octal) */ + status->flags |= E_alt; + ++spec; + break; + case ' ': + /* positive numbers prefixed with ' ' */ + status->flags |= E_space; + ++spec; + break; + case '0': + /* right-aligned padding done with '0' instead of ' ' */ + status->flags |= E_zero; + ++spec; + break; + default: + /* not a flag, exit flag parsing */ + status->flags |= E_done; + break; + } + } while ( ! ( status->flags & E_done ) ); + + /* Optional field width */ + if ( *spec == '*' ) + { + /* Retrieve width value from argument stack */ + int width = va_arg( status->arg, int ); + if ( width < 0 ) + { + status->flags |= E_minus; + status->width = abs( width ); + } + else + { + status->width = width; + } + ++spec; + } + else + { + /* 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 precision */ + if ( *spec == '.' ) + { + ++spec; + if ( *spec == '*' ) + { + /* Retrieve precision value from argument stack. A negative value + is as if no precision is given - as precision is initalized to + EOF (negative), there is no need for testing for negative here. + */ + status->prec = va_arg( status->arg, int ); + ++spec; + } + else + { + char * endptr; + status->prec = (int)strtol( spec, &endptr, 10 ); + if ( spec == endptr ) + { + /* Decimal point but no number - equals zero */ + status->prec = 0; + } + spec = endptr; + } + /* Having a precision cancels out any zero flag. */ + status->flags &= ~E_zero; + } + + /* 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 + { + /* k -> 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': + /* FALLTHROUGH */ + case 'i': + status->base = 10; + 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_lower | 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': + break; + case 'a': + case 'A': + break; + case 'c': + /* TODO: wide chars. */ + { + char c[1]; + c[0] = (char)va_arg( status->arg, int ); + status->flags |= E_char; + stringformat( c, status ); + return ++spec; + } + case 's': + /* TODO: wide chars. */ + stringformat( va_arg( status->arg, char * ), status ); + return ++spec; + case 'p': + status->base = 16; + status->flags |= ( E_lower | E_unsigned | E_alt | E_pointer ); + break; + case 'n': + { + int * val = va_arg( status->arg, int * ); + *val = status->i; + return ++spec; + } + default: + /* No conversion specifier. Bad conversion. */ + return orig_spec; + } + + /* Do the actual output based on our findings */ + if ( status->base != 0 ) + { + /* Integer conversions */ + /* TODO: Check for invalid flag combinations. */ + if ( status->flags & E_unsigned ) + { + uintmax_t value; + switch ( status->flags & ( E_char | E_short | E_long | E_llong | E_size | E_pointer | E_intmax ) ) + { + case E_char: + value = (uintmax_t)(unsigned char)va_arg( status->arg, int ); + break; + case E_short: + value = (uintmax_t)(unsigned short)va_arg( status->arg, int ); + break; + case 0: + value = (uintmax_t)va_arg( status->arg, unsigned int ); + break; + case E_long: + value = (uintmax_t)va_arg( status->arg, unsigned long ); + break; + case E_llong: + value = (uintmax_t)va_arg( status->arg, unsigned long long ); + break; + case E_size: + value = (uintmax_t)va_arg( status->arg, size_t ); + break; + case E_pointer: + value = (uintmax_t)(uintptr_t)va_arg( status->arg, void * ); + break; + case E_intmax: + value = va_arg( status->arg, uintmax_t ); + break; + default: + puts( "UNSUPPORTED PRINTF FLAG COMBINATION" ); + return NULL; + } + INT2BASE(); + } + else + { + intmax_t value; + switch ( status->flags & ( E_char | E_short | E_long | E_llong | E_intmax ) ) + { + case E_char: + value = (intmax_t)(char)va_arg( status->arg, int ); + break; + case E_short: + value = (intmax_t)(short)va_arg( status->arg, int ); + break; + case 0: + value = (intmax_t)va_arg( status->arg, int ); + break; + case E_long: + value = (intmax_t)va_arg( status->arg, long ); + break; + case E_llong: + value = (intmax_t)va_arg( status->arg, long long ); + break; + case E_ptrdiff: + value = (intmax_t)va_arg( status->arg, ptrdiff_t ); + break; + case E_intmax: + value = va_arg( status->arg, intmax_t ); + break; + default: + puts( "UNSUPPORTED PRINTF FLAG COMBINATION" ); + return NULL; + } + INT2BASE(); + } + if ( status->flags & E_minus ) + { + while ( status->current < status->width ) + { + PUT( ' ' ); + ++(status->current); + } + } + if ( status->i >= status->n && status->n > 0 ) + { + status->s[status->n - 1] = '\0'; + } + } + return ++spec; +} + +#endif + +#ifdef TEST +#define _PDCLIB_FILEID "_PDCLIB/print.c" +#define _PDCLIB_STRINGIO + +#include "_PDCLIB_test.h" + +#ifndef REGTEST + +static int testprintf( char * buffer, const char * format, ... ) +{ + /* Members: base, flags, n, i, current, s, width, prec, stream, arg */ + struct _PDCLIB_status_t status; + status.base = 0; + status.flags = 0; + status.n = 100; + status.i = 0; + status.current = 0; + status.s = buffer; + status.width = 0; + status.prec = EOF; + status.stream = NULL; + va_start( status.arg, format ); + memset( buffer, '\0', 100 ); + if ( *(_PDCLIB_print( format, &status )) != '\0' ) + { + printf( "_PDCLIB_print() did not return end-of-specifier on '%s'.\n", format ); + ++TEST_RESULTS; + } + va_end( status.arg ); + return status.i; +} + +#endif + +#define TEST_CONVERSION_ONLY + +int main( void ) +{ +#ifndef REGTEST + char target[100]; +#include "printf_testcases.h" +#endif + return TEST_RESULTS; +} + +#endif |