util_str.c

samba-3.0.22.tar.gz 编译smb服务器的源码

/* 
   Unix SMB/CIFS implementation.
   Samba utility functions
   
   Copyright (C) Andrew Tridgell 1992-2001
   Copyright (C) Simo Sorce      2001-2002
   Copyright (C) Martin Pool     2003
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"

/**
 * @file
 * @brief String utilities.
 **/

/**
 * Get the next token from a string, return False if none found.
 * Handles double-quotes.
 * 
 * Based on a routine by [e-mail]. 
 * Extensively modified by [e-mail]
 **/
BOOL next_token(const char **ptr,char *buff, const char *sep, size_t bufsize)
{
	char *s;
	char *pbuf;
	BOOL quoted;
	size_t len=1;

	if (!ptr)
		return(False);

	s = (char *)*ptr;

	/* default to simple separators */
	if (!sep)
		sep = " \t\n\r";

	/* find the first non sep char */
	while (*s && strchr_m(sep,*s))
		s++;
	
	/* nothing left? */
	if (! *s)
		return(False);
	
	/* copy over the token */
	pbuf = buff;
	for (quoted = False; len < bufsize && *s && (quoted || !strchr_m(sep,*s)); s++) {
		if ( *s == '\"' ) {
			quoted = !quoted;
		} else {
			len++;
			*pbuf++ = *s;
		}
	}
	
	*ptr = (*s) ? s+1 : s;  
	*pbuf = 0;
	
	return(True);
}

/**
This is like next_token but is not re-entrant and "remembers" the first 
parameter so you can pass NULL. This is useful for user interface code
but beware the fact that it is not re-entrant!
**/

static const char *last_ptr=NULL;

BOOL next_token_nr(const char **ptr,char *buff, const char *sep, size_t bufsize)
{
	BOOL ret;
	if (!ptr)
		ptr = &last_ptr;

	ret = next_token(ptr, buff, sep, bufsize);
	last_ptr = *ptr;
	return ret;	
}

static uint16 tmpbuf[sizeof(pstring)];

void set_first_token(char *ptr)
{
	last_ptr = ptr;
}

/**
 Convert list of tokens to array; dependent on above routine.
 Uses last_ptr from above - bit of a hack.
**/

char **toktocliplist(int *ctok, const char *sep)
{
	char *s=(char *)last_ptr;
	int ictok=0;
	char **ret, **iret;

	if (!sep)
		sep = " \t\n\r";

	while(*s && strchr_m(sep,*s))
		s++;

	/* nothing left? */
	if (!*s)
		return(NULL);

	do {
		ictok++;
		while(*s && (!strchr_m(sep,*s)))
			s++;
		while(*s && strchr_m(sep,*s))
			*s++=0;
	} while(*s);
	
	*ctok=ictok;
	s=(char *)last_ptr;
	
	if (!(ret=iret=SMB_MALLOC_ARRAY(char *,ictok+1)))
		return NULL;
	
	while(ictok--) {    
		*iret++=s;
		if (ictok > 0) {
			while(*s++)
				;
			while(!*s)
				s++;
		}
	}

	ret[*ctok] = NULL;
	return ret;
}

/**
 * Case insensitive string compararison.
 *
 * iconv does not directly give us a way to compare strings in
 * arbitrary unix character sets -- all we can is convert and then
 * compare.  This is expensive.
 *
 * As an optimization, we do a first pass that considers only the
 * prefix of the strings that is entirely 7-bit.  Within this, we
 * check whether they have the same value.
 *
 * Hopefully this will often give the answer without needing to copy.
 * In particular it should speed comparisons to literal ascii strings
 * or comparisons of strings that are "obviously" different.
 *
 * If we find a non-ascii character we fall back to converting via
 * iconv.
 *
 * This should never be slower than convering the whole thing, and
 * often faster.
 *
 * A different optimization would be to compare for bitwise equality
 * in the binary encoding.  (It would be possible thought hairy to do
 * both simultaneously.)  But in that case if they turn out to be
 * different, we'd need to restart the whole thing.
 *
 * Even better is to implement strcasecmp for each encoding and use a
 * function pointer. 
 **/
int StrCaseCmp(const char *s, const char *t)
{

	const char *ps, *pt;
	size_t size;
	smb_ucs2_t *buffer_s, *buffer_t;
	int ret;

	for (ps = s, pt = t; ; ps++, pt++) {
		char us, ut;

		if (!*ps && !*pt)
			return 0; /* both ended */
 		else if (!*ps)
			return -1; /* s is a prefix */
		else if (!*pt)
			return +1; /* t is a prefix */
		else if ((*ps & 0x80) || (*pt & 0x80))
			/* not ascii anymore, do it the hard way from here on in */
			break;

		us = toupper_ascii(*ps);
		ut = toupper_ascii(*pt);
		if (us == ut)
			continue;
		else if (us < ut)
			return -1;
		else if (us > ut)
			return +1;
	}

	size = push_ucs2_allocate(&buffer_s, ps);
	if (size == (size_t)-1) {
		return strcmp(ps, pt); 
		/* Not quite the right answer, but finding the right one
		   under this failure case is expensive, and it's pretty close */
	}
	
	size = push_ucs2_allocate(&buffer_t, pt);
	if (size == (size_t)-1) {
		SAFE_FREE(buffer_s);
		return strcmp(ps, pt); 
		/* Not quite the right answer, but finding the right one
		   under this failure case is expensive, and it's pretty close */
	}
	
	ret = strcasecmp_w(buffer_s, buffer_t);
	SAFE_FREE(buffer_s);
	SAFE_FREE(buffer_t);
	return ret;
}


/**
 Case insensitive string compararison, length limited.
**/
int StrnCaseCmp(const char *s, const char *t, size_t n)
{
	pstring buf1, buf2;
	unix_strupper(s, strlen(s)+1, buf1, sizeof(buf1));
	unix_strupper(t, strlen(t)+1, buf2, sizeof(buf2));
	return strncmp(buf1,buf2,n);
}

/**
 * Compare 2 strings.
 *
 * @note The comparison is case-insensitive.
 **/
BOOL strequal(const char *s1, const char *s2)
{
	if (s1 == s2)
		return(True);
	if (!s1 || !s2)
		return(False);
  
	return(StrCaseCmp(s1,s2)==0);
}

/**
 * Compare 2 strings up to and including the nth char.
 *
 * @note The comparison is case-insensitive.
 **/
BOOL strnequal(const char *s1,const char *s2,size_t n)
{
	if (s1 == s2)
		return(True);
	if (!s1 || !s2 || !n)
		return(False);
  
	return(StrnCaseCmp(s1,s2,n)==0);
}

/**
 Compare 2 strings (case sensitive).
**/

BOOL strcsequal(const char *s1,const char *s2)
{
	if (s1 == s2)
		return(True);
	if (!s1 || !s2)
		return(False);
  
	return(strcmp(s1,s2)==0);
}

/**
Do a case-insensitive, whitespace-ignoring string compare.
**/

int strwicmp(const char *psz1, const char *psz2)
{
	/* if BOTH strings are NULL, return TRUE, if ONE is NULL return */
	/* appropriate value. */
	if (psz1 == psz2)
		return (0);
	else if (psz1 == NULL)
		return (-1);
	else if (psz2 == NULL)
		return (1);

	/* sync the strings on first non-whitespace */
	while (1) {
		while (isspace((int)*psz1))
			psz1++;
		while (isspace((int)*psz2))
			psz2++;
		if (toupper_ascii(*psz1) != toupper_ascii(*psz2) || *psz1 == '\0'
		    || *psz2 == '\0')
			break;
		psz1++;
		psz2++;
	}
	return (*psz1 - *psz2);
}


/**
 Convert a string to upper case, but don't modify it.
**/

char *strupper_static(const char *s)
{
	static pstring str;

	pstrcpy(str, s);
	strupper_m(str);

	return str;
}

/**
 Convert a string to "normal" form.
**/

void strnorm(char *s, int case_default)
{
	if (case_default == CASE_UPPER)
		strupper_m(s);
	else
		strlower_m(s);
}

/**
 Check if a string is in "normal" case.
**/

BOOL strisnormal(const char *s, int case_default)
{
	if (case_default == CASE_UPPER)
		return(!strhaslower(s));
	
	return(!strhasupper(s));
}


/**
 String replace.
 NOTE: oldc and newc must be 7 bit characters
**/

void string_replace( pstring s, char oldc, char newc )
{
	char *p;

	/* this is quite a common operation, so we want it to be
	   fast. We optimise for the ascii case, knowing that all our
	   supported multi-byte character sets are ascii-compatible
	   (ie. they match for the first 128 chars) */

	for (p = s; *p; p++) {
		if (*p & 0x80) /* mb string - slow path. */
			break;
		if (*p == oldc)
			*p = newc;
	}

	if (!*p)
		return;

	/* Slow (mb) path. */
#ifdef BROKEN_UNICODE_COMPOSE_CHARACTERS
	/* With compose characters we must restart from the beginning. JRA. */
	p = s;
#endif
	push_ucs2(NULL, tmpbuf, p, sizeof(tmpbuf), STR_TERMINATE);
	string_replace_w(tmpbuf, UCS2_CHAR(oldc), UCS2_CHAR(newc));
	pull_ucs2(NULL, p, tmpbuf, -1, sizeof(tmpbuf), STR_TERMINATE);
}

/**
 Skip past some strings in a buffer.
**/

char *skip_string(char *buf,size_t n)
{
	while (n--)
		buf += strlen(buf) + 1;
	return(buf);
}

/**
 Count the number of characters in a string. Normally this will
 be the same as the number of bytes in a string for single byte strings,
 but will be different for multibyte.
**/

size_t str_charnum(const char *s)
{
	uint16 tmpbuf2[sizeof(pstring)];
	push_ucs2(NULL, tmpbuf2,s, sizeof(tmpbuf2), STR_TERMINATE);
	return strlen_w(tmpbuf2);
}

/**
 Count the number of characters in a string. Normally this will
 be the same as the number of bytes in a string for single byte strings,
 but will be different for multibyte.
**/

size_t str_ascii_charnum(const char *s)
{
	pstring tmpbuf2;
	push_ascii(tmpbuf2, s, sizeof(tmpbuf2), STR_TERMINATE);
	return strlen(tmpbuf2);
}

BOOL trim_char(char *s,char cfront,char cback)
{
	BOOL ret = False;
	char *ep;
	char *fp = s;

	/* Ignore null or empty strings. */
	if (!s || (s[0] == '\0'))
		return False;

	if (cfront) {
		while (*fp && *fp == cfront)
			fp++;
		if (!*fp) {
			/* We ate the string. */
			s[0] = '\0';
			return True;
		}
		if (fp != s)
			ret = True;
	}

	ep = fp + strlen(fp) - 1;
	if (cback) {
		/* Attempt ascii only. Bail for mb strings. */
		while ((ep >= fp) && (*ep == cback)) {
			ret = True;
			if ((ep > fp) && (((unsigned char)ep[-1]) & 0x80)) {
				/* Could be mb... bail back to tim_string. */
				char fs[2], bs[2];
				if (cfront) {
					fs[0] = cfront;
					fs[1] = '\0';
				}
				bs[0] = cback;
				bs[1] = '\0';
				return trim_string(s, cfront ? fs : NULL, bs);
			} else {
				ep--;
			}
		}
		if (ep < fp) {
			/* We ate the string. */
			s[0] = '\0';
			return True;
		}
	}

	ep[1] = '\0';
	memmove(s, fp, ep-fp+2);
	return ret;
}

/**
 Trim the specified elements off the front and back of a string.
**/

BOOL trim_string(char *s,const char *front,const char *back)
{
	BOOL ret = False;
	size_t front_len;
	size_t back_len;
	size_t len;

	/* Ignore null or empty strings. */
	if (!s || (s[0] == '\0'))
		return False;

	front_len	= front? strlen(front) : 0;
	back_len	= back? strlen(back) : 0;

	len = strlen(s);

	if (front_len) {
		while (len && strncmp(s, front, front_len)==0) {
			/* Must use memmove here as src & dest can
			 * easily overlap. Found by valgrind. JRA. */
			memmove(s, s+front_len, (len-front_len)+1);
			len -= front_len;
			ret=True;
		}
	}
	
	if (back_len) {
		while ((len >= back_len) && strncmp(s+len-back_len,back,back_len)==0) {
			s[len-back_len]='\0';
			len -= back_len;
			ret=True;
		}
	}
	return ret;
}

/**
 Does a string have any uppercase chars in it?
**/

BOOL strhasupper(const char *s)
{
	smb_ucs2_t *ptr;
	push_ucs2(NULL, tmpbuf,s, sizeof(tmpbuf), STR_TERMINATE);
	for(ptr=tmpbuf;*ptr;ptr++)
		if(isupper_w(*ptr))
			return True;
	return(False);
}

/**
 Does a string have any lowercase chars in it?
**/

BOOL strhaslower(const char *s)
{
	smb_ucs2_t *ptr;
	push_ucs2(NULL, tmpbuf,s, sizeof(tmpbuf), STR_TERMINATE);
	for(ptr=tmpbuf;*ptr;ptr++)
		if(islower_w(*ptr))
			return True;
	return(False);
}

/**
 Find the number of 'c' chars in a string
**/

size_t count_chars(const char *s,char c)
{
	smb_ucs2_t *ptr;
	int count;
	smb_ucs2_t *alloc_tmpbuf = NULL;

	if (push_ucs2_allocate(&alloc_tmpbuf, s) == (size_t)-1) {
		return 0;
	}

	for(count=0,ptr=alloc_tmpbuf;*ptr;ptr++)
		if(*ptr==UCS2_CHAR(c))
			count++;

	SAFE_FREE(alloc_tmpbuf);
	return(count);
}

/**
 Safe string copy into a known length string. maxlength does not
 include the terminating zero.
**/

char *safe_strcpy_fn(const char *fn, int line, char *dest,const char *src, size_t maxlength)
{