db.c

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/***************************************************************
 *                                                             *
 * Copyright(c) 2001-2005 McObject,LLC. All Right Reserved.    *
 *                                                             *
 ***************************************************************/

/* 
 * This sample shows how to use mco_db_save() and mco_db_load() APIs. These APIs are
 * used to save and load in-memory database to and from any stream device, such as
 * a file or socket.
 * The application presented here was used as actual test to verify the "correctness"
 * of the save and load operations. The schema file dbtest.mco describes declares classes
 * with various data types and various layouts.
 *
 * The project consists of several C files:
 *
 * dbinit.c - functions to initialize the database with the test data.
 * db.c - main driver.
 * dbtest.c - generated interface implemetation file
 * strm.c - FILE stream implemetaion
 * verify.c - functions that read the database back after it has been loaded with mco_db_load
 *            and validates the results.
 */

#include "platform.h"
#include "load.h"
#include "mcoxml.h"

const int MAP_ADDRESS = 0x20000000;

static void _SH_(void)
{

    char text[] = 
    {
        "\nThis sample shows how to use mco_xml_export() and mco_xml_import() APIs.\n"
            "These APIs are used to export and import in-memory database in form of XML document to and from\n"
            "any stream device, such as a file or a socket.\n"
            "The application presented here was used as an actual test to verify the\n"
            "\"correctness\" of the save and load operations. It populates a database\n"
            "that contains classes with the \"fixed\", and \"dynamaic\" fields, a class\n"
            "with blobs, a class with declared with \"autoid\" and \"histoty\", etc.\n"
            "The applicataion then saves the database to the file, closes the connection,\n"
            "re-opens the database and loads the saved image into the memory. It then\n"
            "performs sanity check on the loaded data and prints out the results\n"
    };

    char text1[] = 
    {
        "Copyright(c) 2001-2003 McObject,LLC. All Right Reserved.\n\n"
    };

    printf("%s\neXtremeDB runtime version %d.%d, build %d\n%s\n\nPress Enter to start", text, MCO_COMP_VER_MAJOR,
           MCO_COMP_VER_MINOR, MCO_COMP_BUILD_NUM, text1);

    getchar();
}


static void errhandler(int n)
{
    printf("\neXtremeDB runtime fatal error: %d", n);
    getchar();
    exit( - 1);
}


mco_runtime_info_t info;

#define SETUP_POLICY

int main(void)
{
    MCO_RET rc;
    mco_db_h db = 0;
    FILE* f;
    mco_xml_policy_t op, np;
    mco_trans_h t;

    void* start_mem;


    /* setup policy */
    np.blob_coding = MCO_TEXT_BASE64;
    np.encode_lf = MCO_YES;
    np.encode_nat = MCO_YES;
    np.encode_spec = MCO_YES;
    np.float_format = MCO_FLOAT_FIXED;
    np.ignore_field = MCO_YES;
    np.indent = MCO_YES; /*or MCO_NO*/
    np.int_base = MCO_NUM_DEC;
    np.quad_base = MCO_NUM_HEX; /* other are invalid */
    np.text_coding = MCO_TEXT_ASCII;
    np.truncate_sp = MCO_YES;
    np.use_xml_attrs = MCO_YES;
    np.ignore_autoid = MCO_NO;
    np.ignore_autooid = MCO_NO;

    _SH_();

    mco_get_runtime_info(&info);
    if (!info.mco_save_load_supported)
    {
        printf("This sample requires xml import/export runtime support\n");
        exit(0);
    }

    if (info.mco_shm_supported)
    {
        start_mem = (char*)MAP_ADDRESS;
    }
    else
    {
        start_mem = (char*)malloc(DBSIZE);
        if (!start_mem)
        {
            printf("Couldn't allocated memory\n");
            exit(1);
        }
    };

    mco_error_set_handler(&errhandler);

    mco_runtime_start();
    /* Create a database - allocate 2M starting from mem. */
    rc = mco_db_open("dbtest", dbtest_get_dictionary(), start_mem, DBSIZE, (uint2)PAGESIZE);

    if (rc)
    {
        printf("\nerror creating database");
        if (!info.mco_shm_supported)
        {
            free(start_mem);
        }
        exit(1);
    }

    /* connect to the database, obtain a database handle */
    mco_db_connect("dbtest", &db);

    printf("Initializing database...");
    rc = init_database(db);
    if (rc)
    {
        printf("\tfailed, rc=%d\n\n", rc);
        mco_db_disconnect(db);
        goto end;
    }

    printf("\tsuccess\n");
    printf("Exporting database to %s...", fname);

    f = fopen(fname, "wb");

    /* export content of the database to a file */
    {
        rc = mco_trans_start(db, MCO_READ_WRITE, MCO_TRANS_HIGH, &t);

        if (rc == MCO_S_OK)
        {

            /* setup XML subsystem*/
            #ifdef SETUP_POLICY
                mco_xml_get_policy(t, &op);
                rc = mco_xml_set_policy(t, &np);
                if (MCO_S_OK != rc)
                {
                    printf("unable to set xml policy %d ", rc);
                }
            #endif 
            rc = mco_db_xml_export(t, f, file_writer);

            /* revert xml policy */
            #ifdef SETUP_POLICY
                mco_xml_set_policy(t, &op);
            #endif 

            mco_trans_rollback(t);

            if (rc != MCO_S_OK)
            {
                printf("En error %d occured during exporting.\n", rc);
            }
        }
        else
        {
            printf("Unable to open a transaction. Error code %d\n", rc);
        }
    }
    /**/

    fclose(f);
    if (rc)
    {
        printf("\tfailed, %d\n", rc);
        goto end;
    }
    printf("\tsuccess\n\n");

    /* disconnect from the database, db is no longer valid */
    mco_db_disconnect(db);
    mco_db_close("dbtest");


    {
        rc = mco_db_open("dbtest", dbtest_get_dictionary(), start_mem, DBSIZE, (uint2)PAGESIZE);
        if (rc == MCO_S_OK)
        {

            mco_db_connect("dbtest", &db);

            /* import content of the database from a file */
            rc = mco_trans_start(db, MCO_READ_WRITE, MCO_TRANS_HIGH, &t);

            if (rc == MCO_S_OK)
            {

                #ifdef SETUP_POLICY
                    mco_xml_get_policy(t, &op);
                    rc = mco_xml_set_policy(t, &np);
                    if (MCO_S_OK != rc)
                    {
                        printf("unable to set xml policy %d ", rc);
                    }
                #endif 

                printf("Importing data from %s...", fname);
                f = fopen(fname, "rb");
                rc = mco_db_xml_import(t, f, file_reader);
                fclose(f);

                if (rc)
                {
                    printf("\tfailed. Error code %d\n\n", rc);
                }
                else
                {
                    printf("\tsuccess\n\n");
                }

                #ifdef SETUP_POLICY
                    mco_xml_set_policy(t, &op);
                #endif 

                mco_trans_commit(t);
            }
            /**/

            printf("Verifying data pointers ...");
            rc = verify_db(db);
            if (rc)
            {
                printf("\tfailed\n\n");
            }
            else
            {
                printf("\tsuccess\n\n");
            }

            printf("Verifying object counters...\n\n");
            printf("\tWritten\t%d objects to class \"Dynamic\"\n", nd);
            printf("\tWritten\t%d objects to class \"Fixed\"\n", nf);
            printf("\tWritten\t%d objects to class \"Blobs\"\n", nb);
            printf("\tWritten\t%d versions for class \"Blobs\"\n", nh);

            printf("\tWritten\t%d vector elements to class \"Idxs\"\n\n", ni);
            printf("\tRead\t%d objects from class \"Dynamic\"\n", dv);
            printf("\tRead\t%d objects from class \"Fixed\"\n", fv);
            printf("\tRead\t%d objects from class \"Blobs\"\n", bv);
            printf("\tRead\t%d version from class \"Blobs\"\n", bh);
            printf("\tRead\t%d vector elements from class \"Idxs\"\n\n", iv);

            mco_db_disconnect(db);

            mco_db_close("dbtest");

        }
        else
        {
            printf("Unable to open database. Error code %d\n", rc);
        }
    }


    end: mco_runtime_stop();

    if (!info.mco_shm_supported)
    {
        free(start_mem);
    }

    printf("Press Enter to finish\n");
    getchar();
    PROG_EXIT(0);
}