ex_pack.c

Shows basic packing and unpacking of fields.

/*-
 * Public Domain 2008-2014 WiredTiger, Inc.
 *
 * This is free and unencumbered software released into the public domain.
 *
 * Anyone is free to copy, modify, publish, use, compile, sell, or
 * distribute this software, either in source code form or as a compiled
 * binary, for any purpose, commercial or non-commercial, and by any
 * means.
 *
 * In jurisdictions that recognize copyright laws, the author or authors
 * of this software dedicate any and all copyright interest in the
 * software to the public domain. We make this dedication for the benefit
 * of the public at large and to the detriment of our heirs and
 * successors. We intend this dedication to be an overt act of
 * relinquishment in perpetuity of all present and future rights to this
 * software under copyright law.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * ex_pack.c
 *      This is an example demonstrating basic packing and unpacking of fields.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <wiredtiger.h>

static const char *home;

int
main(void)
{
        WT_CONNECTION *conn;
        WT_SESSION *session;
        char buf[50];
        size_t size;
        int i, j, k, ret;

        /*
         * Create a clean test directory for this run of the test program if the
         * environment variable isn't already set (as is done by make check).
         */
        if (getenv("WIREDTIGER_HOME") == NULL) {
                home = "WT_HOME";
                ret = system("rm -rf WT_HOME && mkdir WT_HOME");
        } else
                home = NULL;

        /* Open a connection to the database, creating it if necessary. */
        if ((ret = wiredtiger_open(home, NULL, "create", &conn)) != 0)
                fprintf(stderr, "Error connecting to %s: %s\n",
                    home, wiredtiger_strerror(ret));

        /* Open a session for the current thread's work. */
        if ((ret = conn->open_session(conn, NULL, NULL, &session)) != 0)
                fprintf(stderr, "Error opening a session on %s: %s\n",
                    home, wiredtiger_strerror(ret));

        ret = wiredtiger_struct_size(session, &size, "iii", 42, 1000, -9);
        if (size > sizeof(buf)) {
                /* Allocate a bigger buffer. */
        }

        ret = wiredtiger_struct_pack(session, buf, size, "iii", 42, 1000, -9);

        ret = wiredtiger_struct_unpack(session, buf, size, "iii", &i, &j, &k);
        /* Note: closing the connection implicitly closes open session(s). */
        if ((ret = conn->close(conn, NULL)) != 0)
                fprintf(stderr, "Error connecting to %s: %s\n",
                    home, wiredtiger_strerror(ret));

        return (ret);
}