sysctl.c

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				left--;
				((char *) buffer)++;
			}
			if (!left)
				break;
			neg = 0;
			len = left;
			if (len > TMPBUFLEN-1)
				len = TMPBUFLEN-1;
			if(copy_from_user(buf, buffer, len))
				return -EFAULT;
			buf[len] = 0;
			p = buf;
			if (*p == '-' && left > 1) {
				neg = 1;
				left--, p++;
			}
			if (*p < '0' || *p > '9')
				break;
			val = simple_strtoul(p, &p, 0);
			len = p-buf;
			if ((len < left) && *p && !isspace(*p))
				break;
			if (neg)
				val = -val;
			buffer += len;
			left -= len;

			if (min && val < *min++)
				continue;
			if (max && val > *max++)
				continue;
			*i = val;
		} else {
			p = buf;
			if (!first)
				*p++ = '\t';
			sprintf(p, "%d", *i);
			len = strlen(buf);
			if (len > left)
				len = left;
			if(copy_to_user(buffer, buf, len))
				return -EFAULT;
			left -= len;
			buffer += len;
		}
	}

	if (!write && !first && left) {
		if(put_user('\n', (char *) buffer))
			return -EFAULT;
		left--, buffer++;
	}
	if (write) {
		p = (char *) buffer;
		while (left) {
			char c;
			if(get_user(c, p++))
				return -EFAULT;
			if (!isspace(c))
				break;
			left--;
		}
	}
	if (write && first)
		return -EINVAL;
	*lenp -= left;
	filp->f_pos += *lenp;
	return 0;
}

static int do_proc_doulongvec_minmax(ctl_table *table, int write,
				     struct file *filp,
				     void *buffer, size_t *lenp,
				     unsigned long convmul,
				     unsigned long convdiv)
{
#define TMPBUFLEN 20
	unsigned long *i, *min, *max, val;
	int vleft, first=1, neg;
	size_t len, left;
	char buf[TMPBUFLEN], *p;
	
	if (!table->data || !table->maxlen || !*lenp ||
	    (filp->f_pos && !write)) {
		*lenp = 0;
		return 0;
	}
	
	i = (unsigned long *) table->data;
	min = (unsigned long *) table->extra1;
	max = (unsigned long *) table->extra2;
	vleft = table->maxlen / sizeof(unsigned long);
	left = *lenp;
	
	for (; left && vleft--; i++, first=0) {
		if (write) {
			while (left) {
				char c;
				if(get_user(c, (char *) buffer))
					return -EFAULT;
				if (!isspace(c))
					break;
				left--;
				((char *) buffer)++;
			}
			if (!left)
				break;
			neg = 0;
			len = left;
			if (len > TMPBUFLEN-1)
				len = TMPBUFLEN-1;
			if(copy_from_user(buf, buffer, len))
				return -EFAULT;
			buf[len] = 0;
			p = buf;
			if (*p == '-' && left > 1) {
				neg = 1;
				left--, p++;
			}
			if (*p < '0' || *p > '9')
				break;
			val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
			len = p-buf;
			if ((len < left) && *p && !isspace(*p))
				break;
			if (neg)
				val = -val;
			buffer += len;
			left -= len;

			if(neg)
				continue;
			if (min && val < *min++)
				continue;
			if (max && val > *max++)
				continue;
			*i = val;
		} else {
			p = buf;
			if (!first)
				*p++ = '\t';
			sprintf(p, "%lu", convdiv * (*i) / convmul);
			len = strlen(buf);
			if (len > left)
				len = left;
			if(copy_to_user(buffer, buf, len))
				return -EFAULT;
			left -= len;
			buffer += len;
		}
	}

	if (!write && !first && left) {
		if(put_user('\n', (char *) buffer))
			return -EFAULT;
		left--, buffer++;
	}
	if (write) {
		p = (char *) buffer;
		while (left) {
			char c;
			if(get_user(c, p++))
				return -EFAULT;
			if (!isspace(c))
				break;
			left--;
		}
	}
	if (write && first)
		return -EINVAL;
	*lenp -= left;
	filp->f_pos += *lenp;
	return 0;
#undef TMPBUFLEN
}

/**
 * proc_doulongvec_minmax - read a vector of long integers with min/max values
 * @table: the sysctl table
 * @write: %TRUE if this is a write to the sysctl file
 * @filp: the file structure
 * @buffer: the user buffer
 * @lenp: the size of the user buffer
 *
 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
 * values from/to the user buffer, treated as an ASCII string.
 *
 * This routine will ensure the values are within the range specified by
 * table->extra1 (min) and table->extra2 (max).
 *
 * Returns 0 on success.
 */
int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
			   void *buffer, size_t *lenp)
{
    return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, 1l, 1l);
}

/**
 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
 * @table: the sysctl table
 * @write: %TRUE if this is a write to the sysctl file
 * @filp: the file structure
 * @buffer: the user buffer
 * @lenp: the size of the user buffer
 *
 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
 * values from/to the user buffer, treated as an ASCII string. The values
 * are treated as milliseconds, and converted to jiffies when they are stored.
 *
 * This routine will ensure the values are within the range specified by
 * table->extra1 (min) and table->extra2 (max).
 *
 * Returns 0 on success.
 */
int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
				      struct file *filp,
				      void *buffer, size_t *lenp)
{
    return do_proc_doulongvec_minmax(table, write, filp, buffer,
				     lenp, HZ, 1000l);
}


/**
 * proc_dointvec_jiffies - read a vector of integers as seconds
 * @table: the sysctl table
 * @write: %TRUE if this is a write to the sysctl file
 * @filp: the file structure
 * @buffer: the user buffer
 * @lenp: the size of the user buffer
 *
 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
 * values from/to the user buffer, treated as an ASCII string. 
 * The values read are assumed to be in seconds, and are converted into
 * jiffies.
 *
 * Returns 0 on success.
 */
int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
			  void *buffer, size_t *lenp)
{
    return do_proc_dointvec(table,write,filp,buffer,lenp,HZ,OP_SET);
}

#else /* CONFIG_PROC_FS */

int proc_dostring(ctl_table *table, int write, struct file *filp,
		  void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
			    void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec(ctl_table *table, int write, struct file *filp,
		  void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
			void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
		    void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
		    void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
		    void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
				      struct file *filp,
				      void *buffer, size_t *lenp)
{
    return -ENOSYS;
}


#endif /* CONFIG_PROC_FS */


/*
 * General sysctl support routines 
 */

/* The generic string strategy routine: */
int sysctl_string(ctl_table *table, int *name, int nlen,
		  void *oldval, size_t *oldlenp,
		  void *newval, size_t newlen, void **context)
{
	size_t l, len;
	
	if (!table->data || !table->maxlen) 
		return -ENOTDIR;
	
	if (oldval && oldlenp) {
		if(get_user(len, oldlenp))
			return -EFAULT;
		if (len) {
			l = strlen(table->data);
			if (len > l) len = l;
			if (len >= table->maxlen)
				len = table->maxlen;
			if(copy_to_user(oldval, table->data, len))
				return -EFAULT;
			if(put_user(0, ((char *) oldval) + len))
				return -EFAULT;
			if(put_user(len, oldlenp))
				return -EFAULT;
		}
	}
	if (newval && newlen) {
		len = newlen;
		if (len > table->maxlen)
			len = table->maxlen;
		if(copy_from_user(table->data, newval, len))
			return -EFAULT;
		if (len == table->maxlen)
			len--;
		((char *) table->data)[len] = 0;
	}
	return 0;
}

/*
 * This function makes sure that all of the integers in the vector
 * are between the minimum and maximum values given in the arrays
 * table->extra1 and table->extra2, respectively.
 */
int sysctl_intvec(ctl_table *table, int *name, int nlen,
		void *oldval, size_t *oldlenp,
		void *newval, size_t newlen, void **context)
{
	int i, *vec, *min, *max;
	size_t length;

	if (newval && newlen) {
		if (newlen % sizeof(int) != 0)
			return -EINVAL;

		if (!table->extra1 && !table->extra2)
			return 0;

		if (newlen > table->maxlen)
			newlen = table->maxlen;
		length = newlen / sizeof(int);

		vec = (int *) newval;
		min = (int *) table->extra1;
		max = (int *) table->extra2;

		for (i = 0; i < length; i++) {
			int value;
			get_user(value, vec + i);
			if (min && value < min[i])
				return -EINVAL;
			if (max && value > max[i])
				return -EINVAL;
		}
	}
	return 0;
}

/* Strategy function to convert jiffies to seconds */ 
int sysctl_jiffies(ctl_table *table, int *name, int nlen,
		void *oldval, size_t *oldlenp,
		void *newval, size_t newlen, void **context)
{
	if (oldval) {
		size_t olen;
		if (oldlenp) { 
			if (get_user(olen, oldlenp))
				return -EFAULT;
			if (olen!=sizeof(int))
				return -EINVAL; 
		}
		if (put_user(*(int *)(table->data) / HZ, (int *)oldval) || 
		    (oldlenp && put_user(sizeof(int),oldlenp)))
			return -EFAULT;
	}
	if (newval && newlen) { 
		int new;
		if (newlen != sizeof(int))
			return -EINVAL; 
		if (get_user(new, (int *)newval))
			return -EFAULT;
		*(int *)(table->data) = new*HZ; 
	}
	return 1;
}


#else /* CONFIG_SYSCTL */


extern asmlinkage long sys_sysctl(struct __sysctl_args *args)
{
	return -ENOSYS;
}

int sysctl_string(ctl_table *table, int *name, int nlen,
		  void *oldval, size_t *oldlenp,
		  void *newval, size_t newlen, void **context)
{
	return -ENOSYS;
}

int sysctl_intvec(ctl_table *table, int *name, int nlen,
		void *oldval, size_t *oldlenp,
		void *newval, size_t newlen, void **context)
{
	return -ENOSYS;
}

int sysctl_jiffies(ctl_table *table, int *name, int nlen,
		void *oldval, size_t *oldlenp,
		void *newval, size_t newlen, void **context)
{
	return -ENOSYS;
}

int proc_dostring(ctl_table *table, int write, struct file *filp,
		  void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec(ctl_table *table, int write, struct file *filp,
		  void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
			void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
		    void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
			  void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
		    void *buffer, size_t *lenp)
{
	return -ENOSYS;
}

int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
				      struct file *filp,
				      void *buffer, size_t *lenp)
{
    return -ENOSYS;
}

struct ctl_table_header * register_sysctl_table(ctl_table * table, 
						int insert_at_head)
{
	return 0;
}

void unregister_sysctl_table(struct ctl_table_header * table)
{
}

#endif /* CONFIG_SYSCTL */