util.c

samba-3.0.22.tar.gz 编译smb服务器的源码

}

/*******************************************************************
 Reduce a file name, removing .. elements.
********************************************************************/

void dos_clean_name(char *s)
{
	char *p=NULL;

	DEBUG(3,("dos_clean_name [%s]\n",s));

	/* remove any double slashes */
	all_string_sub(s, "\\\\", "\\", 0);

	while ((p = strstr_m(s,"\\..\\")) != NULL) {
		pstring s1;

		*p = 0;
		pstrcpy(s1,p+3);

		if ((p=strrchr_m(s,'\\')) != NULL)
			*p = 0;
		else
			*s = 0;
		pstrcat(s,s1);
	}  

	trim_string(s,NULL,"\\..");

	all_string_sub(s, "\\.\\", "\\", 0);
}

/*******************************************************************
 Reduce a file name, removing .. elements. 
********************************************************************/

void unix_clean_name(char *s)
{
	char *p=NULL;

	DEBUG(3,("unix_clean_name [%s]\n",s));

	/* remove any double slashes */
	all_string_sub(s, "//","/", 0);

	/* Remove leading ./ characters */
	if(strncmp(s, "./", 2) == 0) {
		trim_string(s, "./", NULL);
		if(*s == 0)
			pstrcpy(s,"./");
	}

	while ((p = strstr_m(s,"/../")) != NULL) {
		pstring s1;

		*p = 0;
		pstrcpy(s1,p+3);

		if ((p=strrchr_m(s,'/')) != NULL)
			*p = 0;
		else
			*s = 0;
		pstrcat(s,s1);
	}  

	trim_string(s,NULL,"/..");
}

/*******************************************************************
 Close the low 3 fd's and open dev/null in their place.
********************************************************************/

void close_low_fds(BOOL stderr_too)
{
#ifndef VALGRIND
	int fd;
	int i;

	close(0);
	close(1); 

	if (stderr_too)
		close(2);

	/* try and use up these file descriptors, so silly
		library routines writing to stdout etc won't cause havoc */
	for (i=0;i<3;i++) {
		if (i == 2 && !stderr_too)
			continue;

		fd = sys_open("/dev/null",O_RDWR,0);
		if (fd < 0)
			fd = sys_open("/dev/null",O_WRONLY,0);
		if (fd < 0) {
			DEBUG(0,("Can't open /dev/null\n"));
			return;
		}
		if (fd != i) {
			DEBUG(0,("Didn't get file descriptor %d\n",i));
			return;
		}
	}
#endif
}

/*******************************************************************
 Write data into an fd at a given offset. Ignore seek errors.
********************************************************************/

ssize_t write_data_at_offset(int fd, const char *buffer, size_t N, SMB_OFF_T pos)
{
	size_t total=0;
	ssize_t ret;

	if (pos == (SMB_OFF_T)-1) {
		return write_data(fd, buffer, N);
	}
#if defined(HAVE_PWRITE) || defined(HAVE_PRWITE64)
	while (total < N) {
		ret = sys_pwrite(fd,buffer + total,N - total, pos);
		if (ret == -1 && errno == ESPIPE) {
			return write_data(fd, buffer + total,N - total);
		}
		if (ret == -1) {
			DEBUG(0,("write_data_at_offset: write failure. Error = %s\n", strerror(errno) ));
			return -1;
		}
		if (ret == 0) {
			return total;
		}
		total += ret;
		pos += ret;
	}
	return (ssize_t)total;
#else
	/* Use lseek and write_data. */
	if (sys_lseek(fd, pos, SEEK_SET) == -1) {
		if (errno != ESPIPE) {
			return -1;
		}
	}
	return write_data(fd, buffer, N);
#endif
}

/****************************************************************************
 Set a fd into blocking/nonblocking mode. Uses POSIX O_NONBLOCK if available,
 else
  if SYSV use O_NDELAY
  if BSD use FNDELAY
****************************************************************************/

int set_blocking(int fd, BOOL set)
{
	int val;
#ifdef O_NONBLOCK
#define FLAG_TO_SET O_NONBLOCK
#else
#ifdef SYSV
#define FLAG_TO_SET O_NDELAY
#else /* BSD */
#define FLAG_TO_SET FNDELAY
#endif
#endif

	if((val = sys_fcntl_long(fd, F_GETFL, 0)) == -1)
		return -1;
	if(set) /* Turn blocking on - ie. clear nonblock flag */
		val &= ~FLAG_TO_SET;
	else
		val |= FLAG_TO_SET;
	return sys_fcntl_long( fd, F_SETFL, val);
#undef FLAG_TO_SET
}

/****************************************************************************
 Transfer some data between two fd's.
****************************************************************************/

#ifndef TRANSFER_BUF_SIZE
#define TRANSFER_BUF_SIZE 65536
#endif

ssize_t transfer_file_internal(int infd, int outfd, size_t n, ssize_t (*read_fn)(int, void *, size_t),
						ssize_t (*write_fn)(int, const void *, size_t))
{
	char *buf;
	size_t total = 0;
	ssize_t read_ret;
	ssize_t write_ret;
	size_t num_to_read_thistime;
	size_t num_written = 0;

	if ((buf = SMB_MALLOC(TRANSFER_BUF_SIZE)) == NULL)
		return -1;

	while (total < n) {
		num_to_read_thistime = MIN((n - total), TRANSFER_BUF_SIZE);

		read_ret = (*read_fn)(infd, buf, num_to_read_thistime);
		if (read_ret == -1) {
			DEBUG(0,("transfer_file_internal: read failure. Error = %s\n", strerror(errno) ));
			SAFE_FREE(buf);
			return -1;
		}
		if (read_ret == 0)
			break;

		num_written = 0;
 
		while (num_written < read_ret) {
			write_ret = (*write_fn)(outfd,buf + num_written, read_ret - num_written);
 
			if (write_ret == -1) {
				DEBUG(0,("transfer_file_internal: write failure. Error = %s\n", strerror(errno) ));
				SAFE_FREE(buf);
				return -1;
			}
			if (write_ret == 0)
				return (ssize_t)total;
 
			num_written += (size_t)write_ret;
		}

		total += (size_t)read_ret;
	}

	SAFE_FREE(buf);
	return (ssize_t)total;		
}

SMB_OFF_T transfer_file(int infd,int outfd,SMB_OFF_T n)
{
	return (SMB_OFF_T)transfer_file_internal(infd, outfd, (size_t)n, sys_read, sys_write);
}

/*******************************************************************
 Sleep for a specified number of milliseconds.
********************************************************************/

void smb_msleep(unsigned int t)
{
#if defined(HAVE_NANOSLEEP)
	struct timespec tval;
	int ret;

	tval.tv_sec = t/1000;
	tval.tv_nsec = 1000000*(t%1000);

	do {
		errno = 0;
		ret = nanosleep(&tval, &tval);
	} while (ret < 0 && errno == EINTR && (tval.tv_sec > 0 || tval.tv_nsec > 0));
#else
	unsigned int tdiff=0;
	struct timeval tval,t1,t2;  
	fd_set fds;

	GetTimeOfDay(&t1);
	t2 = t1;
  
	while (tdiff < t) {
		tval.tv_sec = (t-tdiff)/1000;
		tval.tv_usec = 1000*((t-tdiff)%1000);

		/* Never wait for more than 1 sec. */
		if (tval.tv_sec > 1) {
			tval.tv_sec = 1; 
			tval.tv_usec = 0;
		}

		FD_ZERO(&fds);
		errno = 0;
		sys_select_intr(0,&fds,NULL,NULL,&tval);

		GetTimeOfDay(&t2);
		if (t2.tv_sec < t1.tv_sec) {
			/* Someone adjusted time... */
			t1 = t2;
		}

		tdiff = TvalDiff(&t1,&t2);
	}
#endif
}

/****************************************************************************
 Become a daemon, discarding the controlling terminal.
****************************************************************************/

void become_daemon(BOOL Fork)
{
	if (Fork) {
		if (sys_fork()) {
			_exit(0);
		}
	}

  /* detach from the terminal */
#ifdef HAVE_SETSID
	setsid();
#elif defined(TIOCNOTTY)
	{
		int i = sys_open("/dev/tty", O_RDWR, 0);
		if (i != -1) {
			ioctl(i, (int) TIOCNOTTY, (char *)0);      
			close(i);
		}
	}
#endif /* HAVE_SETSID */

	/* Close fd's 0,1,2. Needed if started by rsh */
	close_low_fds(False);  /* Don't close stderr, let the debug system
				  attach it to the logfile */
}

/****************************************************************************
 Put up a yes/no prompt.
****************************************************************************/

BOOL yesno(char *p)
{
	pstring ans;
	printf("%s",p);

	if (!fgets(ans,sizeof(ans)-1,stdin))
		return(False);

	if (*ans == 'y' || *ans == 'Y')
		return(True);

	return(False);
}

#if defined(PARANOID_MALLOC_CHECKER)

/****************************************************************************
 Internal malloc wrapper. Externally visible.
****************************************************************************/

void *malloc_(size_t size)
{
#undef malloc
	return malloc(size);
#define malloc(s) __ERROR_DONT_USE_MALLOC_DIRECTLY
}

/****************************************************************************
 Internal calloc wrapper. Not externally visible.
****************************************************************************/

static void *calloc_(size_t count, size_t size)
{
#undef calloc
	return calloc(count, size);
#define calloc(n,s) __ERROR_DONT_USE_CALLOC_DIRECTLY
}

/****************************************************************************
 Internal realloc wrapper. Not externally visible.
****************************************************************************/

static void *realloc_(void *ptr, size_t size)
{
#undef realloc
	return realloc(ptr, size);
#define realloc(p,s) __ERROR_DONT_USE_RELLOC_DIRECTLY
}

#endif /* PARANOID_MALLOC_CHECKER */

/****************************************************************************
 Type-safe malloc.
****************************************************************************/

void *malloc_array(size_t el_size, unsigned int count)
{
	if (count >= MAX_ALLOC_SIZE/el_size) {
		return NULL;
	}

#if defined(PARANOID_MALLOC_CHECKER)
	return malloc_(el_size*count);
#else
	return malloc(el_size*count);
#endif
}

/****************************************************************************
 Type-safe calloc.
****************************************************************************/

void *calloc_array(size_t size, size_t nmemb)
{
	if (nmemb >= MAX_ALLOC_SIZE/size) {
		return NULL;
	}
#if defined(PARANOID_MALLOC_CHECKER)
	return calloc_(nmemb, size);
#else
	return calloc(nmemb, size);
#endif
}

/****************************************************************************
 Expand a pointer to be a particular size.
****************************************************************************/

void *Realloc(void *p,size_t size)
{
	void *ret=NULL;

	if (size == 0) {
		SAFE_FREE(p);
		DEBUG(5,("Realloc asked for 0 bytes\n"));
		return NULL;
	}

#if defined(PARANOID_MALLOC_CHECKER)
	if (!p)
		ret = (void *)malloc_(size);
	else
		ret = (void *)realloc_(p,size);
#else
	if (!p)
		ret = (void *)malloc(size);
	else
		ret = (void *)realloc(p,size);
#endif

	if (!ret)
		DEBUG(0,("Memory allocation error: failed to expand to %d bytes\n",(int)size));

	return(ret);
}

/****************************************************************************
 Type-safe realloc.
****************************************************************************/

void *realloc_array(void *p,size_t el_size, unsigned int count)
{
	if (count >= MAX_ALLOC_SIZE/el_size) {
		return NULL;
	}
	return Realloc(p,el_size*count);
}

/****************************************************************************
 (Hopefully) efficient array append
****************************************************************************/
void add_to_large_array(TALLOC_CTX *mem_ctx, size_t element_size,
			void *element, void **array, uint32 *num_elements,
			ssize_t *array_size)
{
	if (*array_size < 0)
		return;

	if (*array == NULL) {
		if (*array_size == 0) {
			*array_size = 128;
		}

		if (*array_size >= MAX_ALLOC_SIZE/element_size) {
			goto error;
		}

		if (mem_ctx != NULL)
			*array = TALLOC(mem_ctx, element_size * (*array_size));
		else
			*array = SMB_MALLOC(element_size * (*array_size));

		if (*array == NULL)
			goto error;
	}

	if (*num_elements == *array_size) {
		*array_size *= 2;

		if (*array_size >= MAX_ALLOC_SIZE/element_size) {
			goto error;
		}

		if (mem_ctx != NULL)
			*array = TALLOC_REALLOC(mem_ctx, *array,
						element_size * (*array_size));
		else
			*array = SMB_REALLOC(*array,
					     element_size * (*array_size));

		if (*array == NULL)
			goto error;
	}

	memcpy((char *)(*array) + element_size*(*num_elements),
	       element, element_size);
	*num_elements += 1;

	return;

 error:
	*num_elements = 0;
	*array_size = -1;
}

/****************************************************************************
 Free memory, checks for NULL.
 Use directly SAFE_FREE()
 Exists only because we need to pass a function pointer somewhere --SSS
****************************************************************************/

void safe_free(void *p)
{
	SAFE_FREE(p);
}

/****************************************************************************
 Get my own name and IP.
****************************************************************************/

BOOL get_myname(char *my_name)
{
	pstring hostname;

	*hostname = 0;

	/* get my host name */
	if (gethostname(hostname, sizeof(hostname)) == -1) {
		DEBUG(0,("gethostname failed\n"));
		return False;
	} 

	/* Ensure null termination. */
	hostname[sizeof(hostname)-1] = '\0';