stringutils.c

关系型数据库 Postgresql 6.5.2

/*-------------------------------------------------------------------------
 *
 * stringutils.c
 *	  simple string manipulation routines
 *
 * Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *	  $Header: /usr/local/cvsroot/pgsql/src/bin/psql/stringutils.c,v 1.16 1999/02/13 23:20:41 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>

#include "postgres.h"
#ifndef HAVE_STRDUP
#include "strdup.h"
#endif

#include "stringutils.h"

/* all routines assume null-terminated strings! */

/* The following routines remove whitespaces from the left, right
   and both sides of a string */
/* MODIFIES the string passed in and returns the head of it */

#ifdef NOT_USED
static char *
leftTrim(char *s)
{
	char	   *s2 = s;
	int			shift = 0;
	int			j = 0;

	while (isspace(*s))
	{
		s++;
		shift++;
	}
	if (shift > 0)
	{
		while ((s2[j] = s2[j + shift]) != '\0')
			j++;
	}

	return s2;
}

#endif

char *
rightTrim(char *s)
{
	char	   *sEnd,
			   *bsEnd;
	bool		in_bs = false;

	sEnd = s + strlen(s) - 1;
	while (sEnd >= s && isspace(*sEnd))
		sEnd--;
	bsEnd = sEnd;
	while (bsEnd >= s && *bsEnd == '\\')
	{
		in_bs = (in_bs == false);
		bsEnd--;
	}
	if (in_bs && *sEnd)
		sEnd++;
	if (sEnd < s)
		s[0] = '\0';
	else
		s[sEnd - s + 1] = '\0';
	return s;
}

#ifdef NOT_USED
static char *
doubleTrim(char *s)
{
	strcpy(s, leftTrim(rightTrim(s)));
	return s;
}

#endif

#ifdef STRINGUTILS_TEST
void
testStringUtils()
{
	static char *tests[] = {" goodbye  \n",		/* space on both ends */
		"hello world",			/* no spaces to trim */
		"",						/* empty string */
		"a",					/* string with one char */
		" ",					/* string with one whitespace */
	NULL_STR};

	int			i = 0;

	while (tests[i] != NULL_STR)
	{
		char	   *t;

		t = strdup(tests[i]);
		printf("leftTrim(%s) = ", t);
		printf("%sEND\n", leftTrim(t));
		t = strdup(tests[i]);
		printf("rightTrim(%s) = ", t);
		printf("%sEND\n", rightTrim(t));
		t = strdup(tests[i]);
		printf("doubleTrim(%s) = ", t);
		printf("%sEND\n", doubleTrim(t));
		i++;
	}

}

#endif