misc.c

flex编译器的源代码

/* misc - miscellaneous flex routines */

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Vern Paxson.
 * 
 * The United States Government has rights in this work pursuant
 * to contract no. DE-AC03-76SF00098 between the United States
 * Department of Energy and the University of California.
 *
 * Redistribution and use in source and binary forms are permitted provided
 * that: (1) source distributions retain this entire copyright notice and
 * comment, and (2) distributions including binaries display the following
 * acknowledgement:  ``This product includes software developed by the
 * University of California, Berkeley and its contributors'' in the
 * documentation or other materials provided with the distribution and in
 * all advertising materials mentioning features or use of this software.
 * Neither the name of the University nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

/* $Header: /home/daffy/u0/vern/flex/RCS/misc.c,v 2.47 95/04/28 11:39:39 vern Exp $ */

#include "flexdef.h"


void action_define( defname, value )
char *defname;
int value;
	{
	char buf[MAXLINE];

	if ( (int) strlen( defname ) > MAXLINE / 2 )
		{
		format_pinpoint_message( _( "name \"%s\" ridiculously long" ), 
			defname );
		return;
		}

	sprintf( buf, "#define %s %d\n", defname, value );
	add_action( buf );
	}


void add_action( new_text )
char *new_text;
	{
	int len = strlen( new_text );

	while ( len + action_index >= action_size - 10 /* slop */ )
		{
		int new_size = action_size * 2;

		if ( new_size <= 0 )
			/* Increase just a little, to try to avoid overflow
			 * on 16-bit machines.
			 */
			action_size += action_size / 8;
		else
			action_size = new_size;

		action_array =
			reallocate_character_array( action_array, action_size );
		}

	strcpy( &action_array[action_index], new_text );

	action_index += len;
	}


/* allocate_array - allocate memory for an integer array of the given size */

void *allocate_array( size, element_size )
int size;
size_t element_size;
	{
	register void *mem;
	size_t num_bytes = element_size * size;

	mem = flex_alloc( num_bytes );
	if ( ! mem )
		flexfatal(
			_( "memory allocation failed in allocate_array()" ) );

	return mem;
	}


/* all_lower - true if a string is all lower-case */

int all_lower( str )
register char *str;
	{
	while ( *str )
		{
		if ( ! isascii( (Char) *str ) || ! islower( *str ) )
			return 0;
		++str;
		}

	return 1;
	}


/* all_upper - true if a string is all upper-case */

int all_upper( str )
register char *str;
	{
	while ( *str )
		{
		if ( ! isascii( (Char) *str ) || ! isupper( *str ) )
			return 0;
		++str;
		}

	return 1;
	}


/* bubble - bubble sort an integer array in increasing order
 *
 * synopsis
 *   int v[n], n;
 *   void bubble( v, n );
 *
 * description
 *   sorts the first n elements of array v and replaces them in
 *   increasing order.
 *
 * passed
 *   v - the array to be sorted
 *   n - the number of elements of 'v' to be sorted
 */

void bubble( v, n )
int v[], n;
	{
	register int i, j, k;

	for ( i = n; i > 1; --i )
		for ( j = 1; j < i; ++j )
			if ( v[j] > v[j + 1] )	/* compare */
				{
				k = v[j];	/* exchange */
				v[j] = v[j + 1];
				v[j + 1] = k;
				}
	}


/* check_char - checks a character to make sure it's within the range
 *		we're expecting.  If not, generates fatal error message
 *		and exits.
 */

void check_char( c )
int c;
	{
	if ( c >= CSIZE )
		lerrsf( _( "bad character '%s' detected in check_char()" ),
			readable_form( c ) );

	if ( c >= csize )
		lerrsf(
		_( "scanner requires -8 flag to use the character %s" ),
			readable_form( c ) );
	}



/* clower - replace upper-case letter to lower-case */

Char clower( c )
register int c;
	{
	return (Char) ((isascii( c ) && isupper( c )) ? tolower( c ) : c);
	}


/* copy_string - returns a dynamically allocated copy of a string */

char *copy_string( str )
register const char *str;
	{
	register const char *c1;
	register char *c2;
	char *copy;
	unsigned int size;

	/* find length */
	for ( c1 = str; *c1; ++c1 )
		;

	size = (c1 - str + 1) * sizeof( char );
	copy = (char *) flex_alloc( size );

	if ( copy == NULL )
		flexfatal( _( "dynamic memory failure in copy_string()" ) );

	for ( c2 = copy; (*c2++ = *str++) != 0; )
		;

	return copy;
	}


/* copy_unsigned_string -
 *    returns a dynamically allocated copy of a (potentially) unsigned string
 */

Char *copy_unsigned_string( str )
register Char *str;
	{
	register Char *c;
	Char *copy;

	/* find length */
	for ( c = str; *c; ++c )
		;

	copy = allocate_Character_array( c - str + 1 );

	for ( c = copy; (*c++ = *str++) != 0; )
		;

	return copy;
	}


/* cshell - shell sort a character array in increasing order
 *
 * synopsis
 *
 *   Char v[n];
 *   int n, special_case_0;
 *   cshell( v, n, special_case_0 );
 *
 * description
 *   Does a shell sort of the first n elements of array v.
 *   If special_case_0 is true, then any element equal to 0
 *   is instead assumed to have infinite weight.
 *
 * passed
 *   v - array to be sorted
 *   n - number of elements of v to be sorted
 */

void cshell( v, n, special_case_0 )
Char v[];
int n, special_case_0;
	{
	int gap, i, j, jg;
	Char k;

	for ( gap = n / 2; gap > 0; gap = gap / 2 )
		for ( i = gap; i < n; ++i )
			for ( j = i - gap; j >= 0; j = j - gap )
				{
				jg = j + gap;

				if ( special_case_0 )
					{
					if ( v[jg] == 0 )
						break;

					else if ( v[j] != 0 && v[j] <= v[jg] )
						break;
					}

				else if ( v[j] <= v[jg] )
					break;

				k = v[j];
				v[j] = v[jg];
				v[jg] = k;
				}
	}


/* dataend - finish up a block of data declarations */

void dataend()
	{
	if ( datapos > 0 )
		dataflush();

	/* add terminator for initialization; { for vi */
	outn( "    } ;\n" );

	dataline = 0;
	datapos = 0;
	}


/* dataflush - flush generated data statements */

void dataflush()
	{
	outc( '\n' );

	if ( ++dataline >= NUMDATALINES )
		{
		/* Put out a blank line so that the table is grouped into
		 * large blocks that enable the user to find elements easily.
		 */
		outc( '\n' );
		dataline = 0;
		}

	/* Reset the number of characters written on the current line. */
	datapos = 0;
	}


/* flexerror - report an error message and terminate */

void flexerror( msg )
const char msg[];
	{
	fprintf( stderr, "%s: %s\n", program_name, msg );
	flexend( 1 );
	}


/* flexfatal - report a fatal error message and terminate */

void flexfatal( msg )
const char msg[];
	{
	fprintf( stderr, _( "%s: fatal internal error, %s\n" ),
		program_name, msg );
	exit( 1 );
	}


/* htoi - convert a hexadecimal digit string to an integer value */

int htoi( str )
Char str[];
	{
	unsigned int result;

	(void) sscanf( (char *) str, "%x", &result );

	return result;
	}


/* lerrif - report an error message formatted with one integer argument */

void lerrif( msg, arg )
const char msg[];
int arg;
	{
	char errmsg[MAXLINE];
	(void) sprintf( errmsg, msg, arg );
	flexerror( errmsg );
	}


/* lerrsf - report an error message formatted with one string argument */

void lerrsf( msg, arg )
const char msg[], arg[];
	{
	char errmsg[MAXLINE];

	(void) sprintf( errmsg, msg, arg );
	flexerror( errmsg );
	}


/* line_directive_out - spit out a "#line" statement */

void line_directive_out( output_file, do_infile )
FILE *output_file;
int do_infile;
	{
	char directive[MAXLINE], filename[MAXLINE];
	char *s1, *s2, *s3;
	static char line_fmt[] = "#line %d \"%s\"\n";

	if ( ! gen_line_dirs )
		return;

	if ( (do_infile && ! infilename) || (! do_infile && ! outfilename) )
		/* don't know the filename to use, skip */
		return;

	s1 = do_infile ? infilename : outfilename;
	s2 = filename;
	s3 = &filename[sizeof( filename ) - 2];

	while ( s2 < s3 && *s1 )
		{
		if ( *s1 == '\\' )
			/* Escape the '\' */
			*s2++ = '\\';

		*s2++ = *s1++;
		}

	*s2 = '\0';

	if ( do_infile )
		sprintf( directive, line_fmt, linenum, filename );
	else
		{
		if ( output_file == stdout )
			/* Account for the line directive itself. */
			++out_linenum;

		sprintf( directive, line_fmt, out_linenum, filename );
		}

	/* If output_file is nil then we should put the directive in
	 * the accumulated actions.
	 */
	if ( output_file )
		{
		fputs( directive, output_file );
		}
	else
		add_action( directive );
	}


/* mark_defs1 - mark the current position in the action array as
 *               representing where the user's section 1 definitions end
 *		 and the prolog begins
 */
void mark_defs1()
	{
	defs1_offset = 0;
	action_array[action_index++] = '\0';