ldb_msg.c

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/* 
   ldb database library

   Copyright (C) Andrew Tridgell  2004

     ** NOTE! The following LGPL license applies to the ldb
     ** library. This does NOT imply that all of Samba is released
     ** under the LGPL
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   This library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/

/*
 *  Name: ldb
 *
 *  Component: ldb message component utility functions
 *
 *  Description: functions for manipulating ldb_message structures
 *
 *  Author: Andrew Tridgell
 */

#include "ldb_includes.h"

/*
  create a new ldb_message in a given memory context (NULL for top level)
*/
struct ldb_message *ldb_msg_new(void *mem_ctx)
{
	return talloc_zero(mem_ctx, struct ldb_message);
}

/*
  find an element in a message by attribute name
*/
struct ldb_message_element *ldb_msg_find_element(const struct ldb_message *msg, 
						 const char *attr_name)
{
	unsigned int i;
	for (i=0;i<msg->num_elements;i++) {
		if (ldb_attr_cmp(msg->elements[i].name, attr_name) == 0) {
			return &msg->elements[i];
		}
	}
	return NULL;
}

/*
  see if two ldb_val structures contain exactly the same data
  return 1 for a match, 0 for a mis-match
*/
int ldb_val_equal_exact(const struct ldb_val *v1, const struct ldb_val *v2)
{
	if (v1->length != v2->length) return 0;

	if (v1->length == 0) return 1;

	if (memcmp(v1->data, v2->data, v1->length) == 0) {
		return 1;
	}

	return 0;
}

/*
  find a value in an element
  assumes case sensitive comparison
*/
struct ldb_val *ldb_msg_find_val(const struct ldb_message_element *el, 
				 struct ldb_val *val)
{
	unsigned int i;
	for (i=0;i<el->num_values;i++) {
		if (ldb_val_equal_exact(val, &el->values[i])) {
			return &el->values[i];
		}
	}
	return NULL;
}

/*
  duplicate a ldb_val structure
*/
struct ldb_val ldb_val_dup(void *mem_ctx, const struct ldb_val *v)
{
	struct ldb_val v2;
	v2.length = v->length;
	if (v->data == NULL) {
		v2.data = NULL;
		return v2;
	}

	/* the +1 is to cope with buggy C library routines like strndup
	   that look one byte beyond */
	v2.data = talloc_array(mem_ctx, uint8_t, v->length+1);
	if (!v2.data) {
		v2.length = 0;
		return v2;
	}

	memcpy(v2.data, v->data, v->length);
	((char *)v2.data)[v->length] = 0;
	return v2;
}

/*
  add an empty element to a message
*/
int ldb_msg_add_empty(	struct ldb_message *msg,
			const char *attr_name,
			int flags,
			struct ldb_message_element **return_el)
{
	struct ldb_message_element *els;

	els = talloc_realloc(msg, msg->elements, 
			     struct ldb_message_element, msg->num_elements+1);
	if (!els) {
		errno = ENOMEM;
		return LDB_ERR_OPERATIONS_ERROR;
	}

	els[msg->num_elements].values = NULL;
	els[msg->num_elements].num_values = 0;
	els[msg->num_elements].flags = flags;
	els[msg->num_elements].name = talloc_strdup(els, attr_name);
	if (!els[msg->num_elements].name) {
		errno = ENOMEM;
		return LDB_ERR_OPERATIONS_ERROR;
	}

	msg->elements = els;
	msg->num_elements++;

	if (return_el) {
		*return_el = &els[msg->num_elements-1];
	}

	return LDB_SUCCESS;
}

/*
  add an empty element to a message
*/
int ldb_msg_add(struct ldb_message *msg, 
		const struct ldb_message_element *el, 
		int flags)
{
	/* We have to copy this, just in case *el is a pointer into
	 * what ldb_msg_add_empty() is about to realloc() */
	struct ldb_message_element el_copy = *el;
	if (ldb_msg_add_empty(msg, el->name, flags, NULL) != 0) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	msg->elements[msg->num_elements-1] = el_copy;
	msg->elements[msg->num_elements-1].flags = flags;

	return LDB_SUCCESS;
}

/*
  add a value to a message
*/
int ldb_msg_add_value(struct ldb_message *msg, 
		      const char *attr_name,
		      const struct ldb_val *val,
		      struct ldb_message_element **return_el)
{
	struct ldb_message_element *el;
	struct ldb_val *vals;
	int ret;

	el = ldb_msg_find_element(msg, attr_name);
	if (!el) {
		ret = ldb_msg_add_empty(msg, attr_name, 0, &el);
		if (ret != LDB_SUCCESS) {
			return ret;
		}
	}

	vals = talloc_realloc(msg, el->values, struct ldb_val, el->num_values+1);
	if (!vals) {
		errno = ENOMEM;
		return LDB_ERR_OPERATIONS_ERROR;
	}
	el->values = vals;
	el->values[el->num_values] = *val;
	el->num_values++;

	if (return_el) {
		*return_el = el;
	}

	return LDB_SUCCESS;
}


/*
  add a value to a message, stealing it into the 'right' place
*/
int ldb_msg_add_steal_value(struct ldb_message *msg, 
			    const char *attr_name,
			    struct ldb_val *val)
{
	int ret;
	struct ldb_message_element *el;

	ret = ldb_msg_add_value(msg, attr_name, val, &el);
	if (ret == LDB_SUCCESS) {
		talloc_steal(el->values, val->data);
	}
	return ret;
}


/*
  add a string element to a message
*/
int ldb_msg_add_string(struct ldb_message *msg, 
		       const char *attr_name, const char *str)
{
	struct ldb_val val;

	val.data = discard_const_p(uint8_t, str);
	val.length = strlen(str);

	if (val.length == 0) {
		/* allow empty strings as non-existant attributes */
		return LDB_SUCCESS;
	}

	return ldb_msg_add_value(msg, attr_name, &val, NULL);
}

/*
  add a string element to a message, stealing it into the 'right' place
*/
int ldb_msg_add_steal_string(struct ldb_message *msg, 
			     const char *attr_name, char *str)
{
	struct ldb_val val;

	val.data = (uint8_t *)str;
	val.length = strlen(str);

	return ldb_msg_add_steal_value(msg, attr_name, &val);
}

/*
  add a printf formatted element to a message
*/
int ldb_msg_add_fmt(struct ldb_message *msg, 
		    const char *attr_name, const char *fmt, ...)
{
	struct ldb_val val;
	va_list ap;
	char *str;

	va_start(ap, fmt);
	str = talloc_vasprintf(msg, fmt, ap);
	va_end(ap);

	if (str == NULL) return LDB_ERR_OPERATIONS_ERROR;

	val.data   = (uint8_t *)str;
	val.length = strlen(str);

	return ldb_msg_add_steal_value(msg, attr_name, &val);
}

/*
  compare two ldb_message_element structures
  assumes case senistive comparison
*/
int ldb_msg_element_compare(struct ldb_message_element *el1, 
			    struct ldb_message_element *el2)
{
	unsigned int i;

	if (el1->num_values != el2->num_values) {
		return el1->num_values - el2->num_values;
	}

	for (i=0;i<el1->num_values;i++) {
		if (!ldb_msg_find_val(el2, &el1->values[i])) {
			return -1;
		}
	}

	return 0;
}

/*
  compare two ldb_message_element structures
  comparing by element name
*/
int ldb_msg_element_compare_name(struct ldb_message_element *el1, 
				 struct ldb_message_element *el2)
{
	return ldb_attr_cmp(el1->name, el2->name);
}

/*
  convenience functions to return common types from a message
  these return the first value if the attribute is multi-valued
*/
const struct ldb_val *ldb_msg_find_ldb_val(const struct ldb_message *msg, 
					   const char *attr_name)
{
	struct ldb_message_element *el = ldb_msg_find_element(msg, attr_name);
	if (!el || el->num_values == 0) {
		return NULL;
	}
	return &el->values[0];
}

int ldb_msg_find_attr_as_int(const struct ldb_message *msg, 
			     const char *attr_name,
			     int default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	return strtol((const char *)v->data, NULL, 0);
}

unsigned int ldb_msg_find_attr_as_uint(const struct ldb_message *msg, 
				       const char *attr_name,
				       unsigned int default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	return strtoul((const char *)v->data, NULL, 0);
}

int64_t ldb_msg_find_attr_as_int64(const struct ldb_message *msg, 
				   const char *attr_name,
				   int64_t default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	return strtoll((const char *)v->data, NULL, 0);
}

uint64_t ldb_msg_find_attr_as_uint64(const struct ldb_message *msg, 
				     const char *attr_name,
				     uint64_t default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	return strtoull((const char *)v->data, NULL, 0);
}

double ldb_msg_find_attr_as_double(const struct ldb_message *msg, 
				   const char *attr_name,
				   double default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	return strtod((const char *)v->data, NULL);
}

int ldb_msg_find_attr_as_bool(const struct ldb_message *msg, 
			      const char *attr_name,
			      int default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	if (strcasecmp((const char *)v->data, "FALSE") == 0) {
		return 0;
	}
	if (strcasecmp((const char *)v->data, "TRUE") == 0) {
		return 1;
	}
	return default_value;
}

const char *ldb_msg_find_attr_as_string(const struct ldb_message *msg, 
					const char *attr_name,
					const char *default_value)
{
	const struct ldb_val *v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return default_value;
	}
	return (const char *)v->data;
}

struct ldb_dn *ldb_msg_find_attr_as_dn(struct ldb_context *ldb,
				       void *mem_ctx,
				       const struct ldb_message *msg,
				       const char *attr_name)
{
	struct ldb_dn *res_dn;
	const struct ldb_val *v;

	v = ldb_msg_find_ldb_val(msg, attr_name);
	if (!v || !v->data) {
		return NULL;
	}
	res_dn = ldb_dn_new(mem_ctx, ldb, (const char *)v->data);
	if ( ! ldb_dn_validate(res_dn)) {
		talloc_free(res_dn);
		return NULL;
	}
	return res_dn;
}

/*
  sort the elements of a message by name
*/
void ldb_msg_sort_elements(struct ldb_message *msg)
{
	qsort(msg->elements, msg->num_elements, sizeof(struct ldb_message_element), 
	      (comparison_fn_t)ldb_msg_element_compare_name);
}

/*
  shallow copy a message - copying only the elements array so that the caller
  can safely add new elements without changing the message
*/
struct ldb_message *ldb_msg_copy_shallow(TALLOC_CTX *mem_ctx, 
					 const struct ldb_message *msg)
{
	struct ldb_message *msg2;
	int i;