Files
heimdal/base/data.c
Nicolas Williams f4ba41ebdd Pluggable libheimbase interface for DBs and misc libheimbase enhancements
[Code reviewed by Love Hörnquist Åstrand <lha@kth.se>]

    Added heim_db_*() entry points for dealing with databases, and
    make krb5_aname_to_localname() use it.

    The following enhancements to libheimbase are included:

     - Add heim_data_t and heim_string_t "reference" variants to
       avoid memory copies of potentially large data/strings.

       See heim_data_ref_create() and heim_string_ref_create().

     - Added enhancements to heim_array_t to allow their use for
       queues and stacks, and to improve performance.  See
       heim_array_insert_value().

     - Added XPath-like accessors for heim_object_t.  See
       heim_path_get(), heim_path_copy(), heim_path_create(), and
       heim_path_delete().  These are used extensively in the DB
       framework's generic composition of ACID support and in the
       test_base program

     - Made libheimbase more consistent with Core Foundation naming
       conventions.  See heim_{dict, array}_{get, copy}_value() and
       heim_path_{get, copy}().

     - Added functionality to and fixed bugs in base/json.c:
        - heim_serialize();
        - depth limit for JSON parsing (for DoS protection);
        - pretty-printing;
        - JSON compliance (see below);
        - flag options for parsing and serializing; these are needed
          because of impedance mismatches between heim_object_t and
          JSON (e.g., heim_dict_t allows non-string keys, but JSON
          does not; heimbase supports binary data, while JSON does
          not).

     - Added heim_error_enomem().

     - Enhanced the test_base program to test new functionality and
       to use heim_path*() to better test JSON encoding.  This
       includes some fuzz testing of JSON parsing, and running the
       test under valgrind.

     - Started to add doxygen documentation for libheimbase (but doc
       build for libheimbase is still incomplete).

    Note that there's still some incomplete JSON support:

     - JSON string quoting is not fully implemented;

     - libheimbase lacks support for real numbers, while JSON has
       it -- otherwise libheimbase is a superset of JSON,
       specifically in that any heim_object_t can be a key for an
       associative array.

    The following DB backends are supported natively:

     - "sorted-text", a binary search of sorted (in C locale), flat
       text files;

     - "json", a backend that stores DB contents serialized as JSON
       (this is intended for configuration-like contents).

    The DB framework supports:

     - multiple key/value tables per-DB
     - ACID transactions

    The DB framework also natively implements ACID transactions for
    any DB backends that a) do not provide transactions natively, b)
    do provide lock/unlock/sync methods (even on Windows).  This
    includes autocommit of DB updates outside transactions.

    Future DB enhancements may include:

     - add backends for various DB types (BDB, CDB, MDB, ...);

     - make libhdb use heim_db_t;

     - add a command-line tool for interfacing to databases via
       libheimbase (e.g., to get/set/delete values, create/copy/
       backup DBs, inspect history, check integrity);

     - framework-level transaction logging (with redo and undo
       logging), for generic incremental replication;

     - framework-level DB integrity checking.

       We could store a MAC of the XOR of a hash function applied to
       {key, value} for every entry in the DB, then use this to check
       DB integrity incrementally during incremental replication, as
       well as for the whole DB.
2012-02-05 16:26:32 -06:00

165 lines
4.2 KiB
C

/*
* Copyright (c) 2011 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "baselocl.h"
#include <string.h>
static void
data_dealloc(void *ptr)
{
heim_data_t d = ptr;
heim_octet_string *os = (heim_octet_string *)d;
heim_data_free_f_t *deallocp;
heim_data_free_f_t dealloc;
if (os->data == NULL)
return;
/* Possible string ref */
deallocp = _heim_get_isaextra(os, 0);
dealloc = *deallocp;
if (dealloc != NULL)
dealloc(os->data);
}
static int
data_cmp(void *a, void *b)
{
heim_octet_string *osa = a, *osb = b;
if (osa->length != osb->length)
return osa->length - osb->length;
return memcmp(osa->data, osb->data, osa->length);
}
static unsigned long
data_hash(void *ptr)
{
heim_octet_string *os = ptr;
const unsigned char *s = os->data;
if (os->length < 4)
return os->length;
return s[0] | (s[1] << 8) |
(s[os->length - 2] << 16) | (s[os->length - 1] << 24);
}
struct heim_type_data _heim_data_object = {
HEIM_TID_DATA,
"data-object",
NULL,
data_dealloc,
NULL,
data_cmp,
data_hash
};
/**
* Create a data object
*
* @param string the string to create, must be an utf8 string
*
* @return string object
*/
heim_data_t
heim_data_create(const void *data, size_t length)
{
heim_octet_string *os;
os = _heim_alloc_object(&_heim_data_object, sizeof(*os) + length);
if (os) {
os->data = (uint8_t *)os + sizeof(*os);
os->length = length;
memcpy(os->data, data, length);
}
return (heim_data_t)os;
}
heim_data_t
heim_data_ref_create(const void *data, size_t length,
heim_data_free_f_t dealloc)
{
heim_octet_string *os;
heim_data_free_f_t *deallocp;
os = _heim_alloc_object(&_heim_data_object, sizeof(*os) + length);
if (os) {
os->data = (void *)data;
os->length = length;
deallocp = _heim_get_isaextra(os, 0);
*deallocp = dealloc;
}
return (heim_data_t)os;
}
/**
* Return the type ID of data objects
*
* @return type id of data objects
*/
heim_tid_t
heim_data_get_type_id(void)
{
return HEIM_TID_DATA;
}
/**
* Get the data value of the content.
*
* @param data the data object to get the value from
*
* @return a heim_octet_string
*/
const heim_octet_string *
heim_data_get_data(heim_data_t data)
{
/* Note that this works for data and data_ref objects */
return (const heim_octet_string *)data;
}
const void *
heim_data_get_ptr(heim_data_t data)
{
/* Note that this works for data and data_ref objects */
return ((const heim_octet_string *)data)->data;
}
size_t heim_data_get_length(heim_data_t data)
{
/* Note that this works for data and data_ref objects */
return ((const heim_octet_string *)data)->length;
}