medfall

commit 2f6c2071ad38f3d81f52e7820323fd3aa08f1a80
parent 7d9fb5a0116e5baadbdf3ad667c685ec4fd1defd
Author: Michael Savage <mikejsavage@gmail.com>
Date:   Sat Mar  4 11:02:28 +0200

Add ggformat

Diffstat:
ggformat.cc
 | 
194
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
ggformat.h
 | 
126
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 320 insertions(+), 0 deletions(-)
diff --git a/ggformat.cc b/ggformat.cc
@@ -0,0 +1,194 @@
+#include <ctype.h>
+
+#include "intrinsics.h"
+#include "ggformat.h"
+#include "str.h" // TODO: implement a subset of str
+#include "strtonum.h"
+#include "platform_io.h"
+
+template< typename T >
+static void format_helper( FormatBuffer * fb, const str< 16 > & fmt, const T & x ) {
+	char * dst = fb->buf + fb->len;
+	size_t len = fb->capacity - fb->len;
+
+	if( fb->len >= fb->capacity ) {
+		dst = NULL;
+		len = 0;
+	}
+
+	int printed = snprintf( dst, len, fmt.c_str(), x );
+	fb->len += checked_cast< size_t >( printed );
+}
+
+void format( FormatBuffer * fb, double x, const FormatOpts & opts ) {
+	str< 16 > fmt;
+	fmt += "%";
+	if( opts.left_align ) fmt += "-";
+	if( opts.width != -1 ) fmt += opts.width;
+	if( opts.precision != -1 ) {
+		fmt += ".";
+		fmt += opts.precision;
+	}
+	fmt += "f";
+	format_helper( fb, fmt, x );
+}
+
+void format( FormatBuffer * fb, char x, const FormatOpts & opts ) {
+	str< 16 > fmt;
+	fmt += "%";
+	if( opts.left_align ) fmt += "-";
+	if( opts.width != -1 ) fmt += opts.width;
+	fmt += "c";
+	format_helper( fb, fmt, x );
+}
+
+void format( FormatBuffer * fb, const char * x, const FormatOpts & opts ) {
+	str< 16 > fmt;
+	fmt += "%";
+	if( opts.left_align ) fmt += "-";
+	if( opts.width != -1 ) fmt += opts.width;
+	fmt += "s";
+	format_helper( fb, fmt, x );
+}
+
+void format( FormatBuffer * fb, bool x, const FormatOpts & opts ) {
+	format( fb, x ? "true" : "false", opts );
+}
+
+template< typename T >
+static void int_helper( FormatBuffer * fb, char fmt_decimal, const T & x, const FormatOpts & opts ) {
+	str< 16 > fmt;
+	fmt += "%";
+	if( opts.left_align ) fmt += "-";
+	if( opts.zero_pad ) fmt += "0";
+	if( opts.width != -1 ) fmt += opts.width;
+	if( opts.number_format == FormatOpts::DECIMAL ) {
+		fmt += fmt_decimal;
+	}
+	else if( opts.number_format == FormatOpts::HEX ) {
+		fmt += "x";
+	}
+	else if( opts.number_format == FormatOpts::BINARY ) {
+		ASSERT( !"not implemented" );
+	}
+	format_helper( fb, fmt, x );
+}
+
+void format( FormatBuffer * fb, long long x, const FormatOpts & opts ) {
+	int_helper( fb, 'd', x, opts );
+}
+
+void format( FormatBuffer * fb, unsigned long long x, const FormatOpts & opts ) {
+	int_helper( fb, 'u', x, opts );
+}
+
+#define INT_OVERLOADS( T ) \
+	void format( FormatBuffer * fb, T x, const FormatOpts & opts ) { \
+		format( fb, ( long long ) x, opts ); \
+	} \
+	void format( FormatBuffer * fb, unsigned T x, const FormatOpts & opts ) { \
+		format( fb, ( unsigned long long ) x, opts ); \
+	}
+
+INT_OVERLOADS( short )
+INT_OVERLOADS( int )
+INT_OVERLOADS( long )
+
+#undef INT_OVERLOADS
+
+static const char * parse_format_bool( const char * p, const char * one_past_end, char x, bool * out ) {
+	if( p >= one_past_end ) return p;
+	if( *p != x ) return p;
+	*out = true;
+	return p + 1;
+}
+
+static const char * parse_format_int( const char * p, const char * one_past_end, int * out ) {
+	char num[ 16 ];
+	size_t num_len = 0;
+
+	while( p + num_len < one_past_end && isdigit( p[ num_len ] ) ) {
+		num[ num_len ] = p[ num_len ];
+		num_len++;
+	}
+	num[ num_len ] = '\0';
+
+	if( num_len == 0 ) return p;
+
+	*out = strtonum( num, 1, 1024, NULL );
+	ASSERT( *out != 0 );
+
+	return p + num_len;
+}
+
+static const char * parse_format_precision( const char * p, const char * one_past_end, int * precision ) {
+	bool has_a_dot = false;
+	const char * after_dot = parse_format_bool( p, one_past_end, '.', &has_a_dot );
+	if( !has_a_dot ) return p;
+	return parse_format_int( after_dot, one_past_end, precision );
+}
+
+static const char * parse_format_number_format( const char * p, const char * one_past_end, FormatOpts::NumberFormat * number_format ) {
+	*number_format = FormatOpts::DECIMAL;
+
+	bool hex = false;
+	const char * after_hex = parse_format_bool( p, one_past_end, 'x', &hex );
+
+	if( hex ) {
+		*number_format = FormatOpts::HEX;
+		return after_hex;
+	}
+
+	bool bin = false;
+	const char * after_bin = parse_format_bool( p, one_past_end, 'b', &bin );
+
+	if( bin ) {
+		*number_format = FormatOpts::BINARY;
+		return after_bin;
+	}
+
+	return p;
+}
+
+
+FormatOpts parse_formatopts( const char * fmt, size_t len ) {
+	FormatOpts opts;
+
+	const char * start = fmt;
+	const char * one_past_end = start + len;
+
+	start = parse_format_bool( start, one_past_end, '-', &opts.left_align );
+	start = parse_format_bool( start, one_past_end, '0', &opts.zero_pad );
+	start = parse_format_int( start, one_past_end, &opts.width );
+	start = parse_format_precision( start, one_past_end, &opts.precision );
+	start = parse_format_number_format( start, one_past_end, &opts.number_format );
+
+	ASSERT( start == one_past_end );
+
+	return opts;
+}
+
+static bool strchridx( const char * haystack, char needle, size_t * idx, size_t skip = 0 ) {
+	*idx = skip;
+	while( haystack[ *idx ] != '\0' ) {
+		if( haystack[ *idx ] == needle ) {
+			return true;
+		}
+		( *idx )++;
+	}
+	return false;
+}
+
+bool ggformat_find( const char * str, size_t * start, size_t * one_past_end ) {
+	bool has_open = strchridx( str, '{', start );
+	if( !has_open ) return false;
+	bool has_close = strchridx( str, '}', one_past_end, *start );
+	ASSERT( has_close );
+	return true;
+}
+
+void ggformat_impl( FormatBuffer * fb, const char * fmt ) {
+	size_t ignored;
+	ASSERT( !ggformat_find( fmt, &ignored, &ignored ) );
+	format( fb, fmt );
+}
diff --git a/ggformat.h b/ggformat.h
@@ -0,0 +1,126 @@
+#pragma once
+
+#include <stddef.h>
+
+/*
+ * a type safe replacement for printf
+ */
+
+/*
+ * prototypes of the functions you should be calling
+ */
+template< typename... Rest >
+size_t ggformat( char * buf, size_t len, const char * fmt, Rest... rest );
+
+template< typename... Rest >
+void ggprint_to_file( FILE * file, const char * fmt, Rest... rest );
+
+template< typename... Rest >
+void ggprint( const char * fmt, Rest... rest );
+
+/*
+ * structures and functions used for formatting specific data types
+ */
+
+struct FormatOpts {
+	enum NumberFormat { DECIMAL, HEX, BINARY };
+
+	int width = -1;
+	int precision = -1;
+	bool zero_pad = false;
+	bool left_align = false;
+	NumberFormat number_format = DECIMAL;
+};
+
+struct FormatBuffer {
+	FormatBuffer( char * b, size_t c ) {
+		buf = b;
+		capacity = c;
+		len = 0;
+	}
+
+	char * buf;
+	size_t capacity;
+	size_t len;
+};
+
+/*
+ * format implementations for primitive types
+ */
+
+void format( FormatBuffer * fb, short x, const FormatOpts & opts );
+void format( FormatBuffer * fb, int x, const FormatOpts & opts );
+void format( FormatBuffer * fb, long x, const FormatOpts & opts );
+void format( FormatBuffer * fb, long long x, const FormatOpts & opts );
+void format( FormatBuffer * fb, unsigned short x, const FormatOpts & opts );
+void format( FormatBuffer * fb, unsigned int x, const FormatOpts & opts );
+void format( FormatBuffer * fb, unsigned long x, const FormatOpts & opts );
+void format( FormatBuffer * fb, unsigned long long x, const FormatOpts & opts );
+void format( FormatBuffer * fb, double x, const FormatOpts & opts );
+void format( FormatBuffer * fb, bool x, const FormatOpts & opts );
+void format( FormatBuffer * fb, char x, const FormatOpts & opts );
+void format( FormatBuffer * fb, const char * x, const FormatOpts & opts = FormatOpts() );
+
+/*
+ * nasty implementation details that have to go in the header
+ */
+
+#include "platform_io.h"
+#include "platform_pragmas.h"
+
+FormatOpts parse_formatopts( const char * fmt, size_t len );
+void ggformat_impl( FormatBuffer * fb, const char * fmt );
+bool ggformat_find( const char * str, size_t * start, size_t * one_past_end );
+
+PRAGMA_DISABLE_OPTIMISATIONS();
+
+template< typename T, typename... Rest >
+void ggformat_impl( FormatBuffer * fb, const char * fmt, const T & first, Rest... rest ) {
+	size_t start, one_past_end;
+	bool has_fmt = ggformat_find( fmt, &start, &one_past_end );
+	ASSERT( has_fmt );
+
+	if( fb->len < fb->capacity ) {
+		size_t remaining = fb->capacity - fb->len;
+		size_t to_copy = min( remaining, start + 1 );
+		snprintf( fb->buf + fb->len, to_copy, "%s", fmt );
+	}
+	fb->len += start;
+
+	FormatOpts opts = parse_formatopts( fmt + start + 1, one_past_end - start - 1 );
+	format( fb, first, opts );
+
+	ggformat_impl( fb, fmt + one_past_end + 1, rest... );
+}
+
+template< typename... Rest >
+size_t ggformat( char * buf, size_t len, const char * fmt, Rest... rest ) {
+	FormatBuffer fb( buf, sizeof( len ) );
+	ggformat_impl( &fb, fmt, rest... );
+	return fb.len;
+}
+
+template< typename... Rest >
+void ggprint_to_file( FILE * file, const char * fmt, Rest... rest ) {
+	char buf[ 4096 ];
+	FormatBuffer fb( buf, sizeof( buf ) );
+	ggformat_impl( &fb, fmt, rest... );
+
+	if( fb.len < fb.capacity ) {
+		fprintf( file, "%s", buf );
+		return;
+	}
+
+	char * new_buf = new char[ fb.len + 1 ]();
+	FormatBuffer new_fb( new_buf, fb.len + 1 );
+	ggformat_impl( &new_fb, fmt, rest... );
+	fprintf( file, "%s", new_buf );
+	delete[] new_buf;
+}
+
+template< typename... Rest >
+void ggprint( const char * fmt, Rest... rest ) {
+	ggprint_to_file( stdout, fmt, rest... );
+}
+
+PRAGMA_ENABLE_OPTIMISATIONS();