389-ds-base/ldap/servers/plugins/replication/tests/dnp_sim2.c

/** BEGIN COPYRIGHT BLOCK
 * Copyright (C) 2001 Sun Microsystems, Inc. Used by permission.
 * Copyright (C) 2005 Red Hat, Inc.
 * All rights reserved.
 *
 * License: GPL (version 3 or any later version).
 * See LICENSE for details.
 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

/* dnp_simulation.c - this file varifies the correctness of dnp algorithm
                      by generating random sequences of operations, applying
                      the algorithm and outputing the result

   usage: dnp_sim [-h] [-n <number of simulations> ] [-v] [-f <output file>]
        -h - print usage information.
        -n <number of simulations> - how many simulations to perform; default - 1.
        -v - verbose mode (prints full entry state after each operation execution)
        -f <output file> - file where results are stored; by default results are
                           printed to the screen.
        -o <op file> - file that contains operation sequence to execute; by default,
                       random sequence is generated.
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <memory.h>
#include <string.h>
#include <time.h>
#include <windows.h>

#define MAX_OPS 18  /* maximum number of operations in a simulation */
#define MAX_VALS 10 /* maximum number of values is entry or dn */
#define NOT_PRESENT -1

/* data types */
typedef struct value_state
{
    int value_index;         /* value */
    int presence_csn;        /* last time at which we know the value was present */
    int distinguished_index; /* index into dncsn list */
    int delete_csn;          /* last attempt to delete this value */
    int present;             /* flag that tells whether the value iscurrently present */
} Value_State;

typedef struct dn_csn
{
    int csn;         /* dn csn */
    int value_index; /* dn value */
} Dn_Csn;

typedef struct entry_state
{
    Dn_Csn dn_csns[MAX_VALS + 1]; /* list of dn csns for this entry */
    int dn_csn_count;             /* csn of the current dn */
    Value_State values[MAX_VALS]; /* values of the attribute */
    int attr_delete_csn;          /* last attempt to delete the entire attribute */
} Entry_State;

typedef enum {
    OP_ADD_VALUE,
    OP_DELETE_VALUE,
    OP_RENAME_ENTRY,
    OP_DELETE_ATTR,
    OP_END
} Operation_Type;

typedef struct operation
{
    Operation_Type type; /* operation type */
    int csn;             /* operation type */
    int value_index;     /* value to add, remove or rename from */
} Operation;

typedef struct simulator_params
{
    int runs;        /* number of runs */
    FILE *fout;      /* output file */
    int value_count; /* number of values */
    int verbose;     /* verbose mode */
    Operation *ops;  /* operation sequence to apply */
    int op_count;
} Simulator_Params;


/* gloabl data */
Simulator_Params sim;
char *g_values[] =
    {
        "v",
        "u",
        "w",
        NULL};

/* forward declarations */

/* initialization */
void process_cmd(int argc, char **argv);
void set_default_sim_params();
int count_values();
void parse_operations_file(char *name);
void parse_operation(char *line, int pos);
int value2index(char *value);
void print_usage();

/* simulation run */
void run_simulation();
void generate_operations(Operation **ops, int *op_count);
void generate_operation(Operation *op, int csn);
int *generate_operation_order(int op_count, int seq_num);
void apply_operation_sequence(Operation *ops, int op_count, int *order, Entry_State *entry);
void init_entry_state(Entry_State *entry);
void init_value_state(Value_State *val, int seq_num);
void apply_operation(Entry_State *entry, Operation *op);
void free_operations(Operation **ops);
int **new_perm_table(int op_count);
void free_perm_table(int ***perm_table, int op_count);
int get_perm_count(int op_count);
void generate_perm_table(int *elements, int element_count, int static_part, int **perm_table);
void apply_add_operation(Entry_State *entry, Operation *op);
void apply_value_delete_operation(Entry_State *entry, Operation *op);
void apply_attr_delete_operation(Entry_State *entry, Operation *op);
void apply_rename_operation(Entry_State *entry, Operation *op);
void purge_value_state(Entry_State *entry, int index);
void resolve_value_state(Entry_State *entry, int value_index);
int value_distinguished_at_delete(Entry_State *entry, int value_index);
int compare_entry_state(Entry_State *entry1, Entry_State *entry2, int run);

/* dnc_csn handling */
int dn_csn_add(Entry_State *entry, int value_index, int csn);
int get_value_dn_csn(Entry_State *entry, int value_index);

/* data tracing */
void dump_operations(Operation *ops, int op_count, int *order);
void dump_operation(Operation *op);
void dump_perm_table(int **perm_table, int op_count);
void dump_entry_state(Entry_State *entry);
void dump_value_state(Value_State *value);
void dump_dn_csn_list(Entry_State *entry);

/* misc functions */
int max_val(int a, int b);

int
main(int argc, char **argv)
{
    int i;

    process_cmd(argc, argv);

    for (i = 0; i < sim.runs; i++) {
        fprintf(sim.fout, "*******running simulation #%d ...\n\n", i + 1);
        run_simulation();
        fprintf(sim.fout, "\n*******done with simulation #%d ...\n\n", i + 1);
    }

    if (sim.fout != stdout)
        fclose(sim.fout);

    return 0;
}

void
process_cmd(int argc, char **argv)
{
    int i;

    set_default_sim_params();

    if (argc == 1) {
        return;
    }

    if (strcmp(argv[1], "-h") == 0) /* print help */
    {
        print_usage();
        exit(0);
    }

    i = 1;
    while (i < argc) {
        if (strcmp(argv[i], "-v") == 0) /* verbose mode */
        {
            sim.verbose = 1;
            i++;
        } else if (strcmp(argv[i], "-n") == 0) {
            if (i < argc - 1) {
                int runs = atoi(argv[i + 1]);
                if (runs > 0)
                    sim.runs = runs;
                i += 2;
            } else {
                /* ONREPL print warning */
                i++;
            }
        } else if (strcmp(argv[i], "-f") == 0) /* output file */
        {
            if (i < argc - 1) {
                FILE *f = fopen(argv[i + 1], "w");
                if (f == 0) {
                    printf("failed to open output file; error - %s, using stdout\n",
                           strerror(errno));
                } else {
                    /* ONREPL print warning */
                    sim.fout = f;
                }

                i += 2;
            } else
                i++;
        } else if (strcmp(argv[i], "-o") == 0) /* file with operation sequence */
        {
            if (i < argc - 1) {
                parse_operations_file(argv[i + 1]);
                i += 2;
            } else {
                /* ONREPL print warning */
                i++;
            }
        } else /* unknown option */
        {
            printf("unknown option - %s; ignored\n", argv[i]);
            i++;
        }
    }
}

void
set_default_sim_params()
{
    memset(&sim, 0, sizeof(sim));
    sim.runs = 1;
    sim.fout = stdout;
    sim.value_count = count_values();
}

/* file format: <op count>
                add <value>
                delete <value>
                delete attribute
                rename to <value>

    all spaces are significant
 */
void
parse_operations_file(char *name)
{
    FILE *file = fopen(name, "r");
    char line[256];
    int i;

    if (file == NULL) {
        printf("failed to open operations file %s: error = %d\n", name, errno);
        print_usage();
        exit(1);
    }

    i = 0;
    while (fgets(line, sizeof(line), file)) {
        if (i == 0) {
            /* read operation count */
            sim.op_count = atoi(line);
            if (sim.op_count < 1 || sim.op_count > MAX_OPS / 2) {
                printf("invalid operation count - %d; value must be between 1 and %d\n",
                       sim.op_count, MAX_OPS / 2);
                print_usage();
                exit(1);
            } else {
                sim.ops = (Operation *)malloc(sim.op_count * sizeof(Operation));
            }
        } else {
            if (strlen(line) == 0) /* skip empty lines */
                continue;
            parse_operation(line, i);
        }

        i++;
    }
}

void
parse_operation(char *line, int i)
{
    sim.ops[i - 1].csn = i;

    if (line[strlen(line) - 1] == '\n')
        line[strlen(line) - 1] = '\0';

    if (strncmp(line, "add", 3) == 0) {
        sim.ops[i - 1].type = OP_ADD_VALUE;
        sim.ops[i - 1].value_index = value2index(&line[4]);
    } else if (strncmp(line, "delete attribute", 16) == 0) {
        sim.ops[i - 1].type = OP_DELETE_ATTR;
    } else if (strncmp(line, "delete", 6) == 0) {
        sim.ops[i - 1].type = OP_DELETE_VALUE;
        sim.ops[i - 1].value_index = value2index(&line[7]);
    } else if (strncmp(line, "rename to", 6) == 0) {
        sim.ops[i - 1].type = OP_RENAME_ENTRY;
        sim.ops[i - 1].value_index = value2index(&line[10]);
    } else {
        /* invalid line */
        printf("invalid operation: %s\n", line);
        exit(1);
    }
}

int
value2index(char *value)
{
    int i;

    for (i = 0; i < sim.value_count; i++) {
        if (strcmp(g_values[i], value) == 0)
            return i;
    }

    return -1;
}

void
print_usage()
{
    printf("usage: dnp_sim [-h] [-n <number of simulations> ] [-v] [-f <output file>]\n"
           "\t-h - print usage information\n"
           "\t-n <number of simulations>; default - 1\n"
           "\t-v - verbose mode\n"
           "\t-f <output file> - by default, results are printed to the screen\n"
           "\t-o <op file> - file that contains operation sequence to execute;\n"
           "\tby default, random sequence is generated.\n");
}

int
count_values()
{
    int i;

    for (i = 0; g_values[i]; i++)
        ;

    return i;
}

void
run_simulation()
{
    int *order;
    int i;
    int perm_count;
    Entry_State entry_first, entry_current;
    int error = 0;

    init_entry_state(&entry_first);
    fprintf(sim.fout, "initial entry state :\n");
    dump_entry_state(&entry_first);

    if (sim.ops == NULL) {
        generate_operations(&sim.ops, &sim.op_count);
    }
    fprintf(sim.fout, "initial operation set:\n");
    dump_operations(sim.ops, sim.op_count, NULL /* order */);

    //DebugBreak ();

    perm_count = get_perm_count(sim.op_count);
    for (i = 0; i < perm_count; i++) {
        fprintf(sim.fout, "--------------------------------\n");
        fprintf(sim.fout, "simulation run %d\n", i + 1);
        fprintf(sim.fout, "--------------------------------\n");
        order = generate_operation_order(sim.op_count, i);
        if (i == 0)
            apply_operation_sequence(sim.ops, sim.op_count, order, &entry_first);
        else {
            apply_operation_sequence(sim.ops, sim.op_count, order, &entry_current);
            error |= compare_entry_state(&entry_first, &entry_current, i + 1);
        }
    }

    switch (error) {
    case 0:
        fprintf(sim.fout, "all runs left the entry in the same state\n");
        break;
    case 1:
        fprintf(sim.fout, "while value presence is consistent across all runs, "
                          "the exact state does not match\n");
        break;
    case 3:
        fprintf(sim.fout, "the runs left entries in an inconsistent state\n");
        break;
    }

    free_operations(&sim.ops);
}

void
generate_operations(Operation **ops, int *op_count)
{
    int i;

    /* generate number operations in the sequence */
    *op_count = slapi_rand() % (MAX_OPS / 2) + 1;
    *ops = (Operation *)malloc(*op_count * sizeof(Operation));

    for (i = 0; i < *op_count; i++) {
        generate_operation(&((*ops)[i]), i + 1);
    }
}

void
generate_operation(Operation *op, int csn)
{
    /* generate operation type */
    op->type = slapi_rand() % OP_END;

    /* generate value to which operation applies */
    op->value_index = slapi_rand() % sim.value_count;

    op->csn = csn;
}

int *
generate_operation_order(int op_count, int seq_num)
{
    static int **perm_table = NULL;

    /* first request - generate pemutation table */
    if (seq_num == 0) {
        int elements[MAX_OPS];
        int i;

        if (perm_table)
            free_perm_table(&perm_table, op_count);
        perm_table = new_perm_table(op_count);

        for (i = 0; i < op_count; i++)
            elements[i] = i;

        generate_perm_table(elements, op_count, 0 /* static part */,
                            perm_table);
    }

    return perm_table[seq_num];
}

void
apply_operation_sequence(Operation *ops, int op_count, int *order, Entry_State *entry)
{
    int i;

    init_entry_state(entry);

    if (!sim.verbose) {
        if (!sim.verbose) {
            fprintf(sim.fout, "operation_sequence for this run:\n");
            dump_operations(ops, op_count, order);
        }
    }

    for (i = 0; i < op_count; i++) {
        apply_operation(entry, &(ops[order[i]]));
    }

    if (!sim.verbose) {
        fprintf(sim.fout, "final entry state :\n");
        dump_entry_state(entry);
    }
}

void
init_entry_state(Entry_State *entry)
{
    int i;

    memset(entry, 0, sizeof(*entry));
    entry->attr_delete_csn = NOT_PRESENT;
    entry->dn_csn_count = 1;

    for (i = 0; i < sim.value_count; i++) {
        init_value_state(&(entry->values[i]), i);
    }
}

void
init_value_state(Value_State *val, int seq_num)
{
    memset(val, 0, sizeof(*val));
    val->value_index = seq_num;
    val->present = 1;
    val->delete_csn = NOT_PRESENT;
    if (seq_num > 0) /* only first value is distinguished */
        val->distinguished_index = -1;
}

void
apply_operation(Entry_State *entry, Operation *op)
{
    switch (op->type) {
    case OP_ADD_VALUE:
        apply_add_operation(entry, op);
        break;

    case OP_DELETE_VALUE:
        apply_value_delete_operation(entry, op);
        break;

    case OP_DELETE_ATTR:
        apply_attr_delete_operation(entry, op);
        break;

    case OP_RENAME_ENTRY:
        apply_rename_operation(entry, op);
        break;
    }

    if (sim.verbose) {
        fprintf(sim.fout, "operation: ");
        dump_operation(op);
        fprintf(sim.fout, "\n");
        dump_entry_state(entry);
    }
}

void
free_operations(Operation **ops)
{
    free(*ops);
    *ops = NULL;
}

int **
new_perm_table(int op_count)
{
    int i;
    int **perm_table;
    int perm_count = get_perm_count(op_count);

    perm_table = (int **)malloc(perm_count * sizeof(int *));
    for (i = 0; i < perm_count; i++)
        perm_table[i] = (int *)malloc(op_count * sizeof(int));

    return perm_table;
}

void
free_perm_table(int ***perm_table, int op_count)
{
    int i;
    int perm_count = get_perm_count(op_count);

    for (i = 0; i < perm_count; i++)
        free((*perm_table)[i]);

    free(*perm_table);
    *perm_table = NULL;
}

void
generate_perm_table(int *elements, int element_count, int static_part, int **perm_table)
{
    int i;
    int elements_copy[MAX_OPS];
    int start_pos;

    if (element_count - 1 == static_part) {
        memcpy(*perm_table, elements, element_count * sizeof(int));
        return;
    }

    start_pos = 0;
    for (i = 0; i < element_count - static_part; i++) {
        memcpy(elements_copy, elements, element_count * sizeof(int));
        elements_copy[static_part] = elements[static_part + i];
        elements_copy[static_part + i] = elements[static_part];
        generate_perm_table(elements_copy, element_count, static_part + 1,
                            &perm_table[start_pos]);
        start_pos += get_perm_count(element_count - static_part - 1);
    }
}

int
get_perm_count(int op_count)
{
    int i;
    int perm_count = 1;

    for (i = 2; i <= op_count; i++)
        perm_count *= i;

    return perm_count;
}

void
apply_add_operation(Entry_State *entry, Operation *op)
{
    if (entry->values[op->value_index].presence_csn < op->csn) {
        entry->values[op->value_index].presence_csn = op->csn;
        resolve_value_state(entry, op->value_index);
    }
}

void
apply_value_delete_operation(Entry_State *entry, Operation *op)
{
    if (entry->values[op->value_index].delete_csn < op->csn) {
        entry->values[op->value_index].delete_csn = op->csn;
        resolve_value_state(entry, op->value_index);
    }
}

void
apply_attr_delete_operation(Entry_State *entry, Operation *op)
{
    int i;

    if (entry->attr_delete_csn < op->csn) {
        entry->attr_delete_csn = op->csn;

        for (i = 0; i < sim.value_count; i++) {
            resolve_value_state(entry, i);
        }
    }
}

void
apply_rename_operation(Entry_State *entry, Operation *op)
{
    int index;

    if (entry->values[op->value_index].presence_csn == NOT_PRESENT)
        entry->values[op->value_index].presence_csn = op->csn;

    index = dn_csn_add(entry, op->value_index, op->csn);

    if (index > 0)
        resolve_value_state(entry, entry->dn_csns[index - 1].value_index);

    resolve_value_state(entry, entry->dn_csns[index].value_index);
}

void
purge_value_state(Entry_State *entry, int value_index)
{
    Value_State *value = &(entry->values[value_index]);
    int value_distinguished_csn = get_value_dn_csn(entry, value_index);

    if (value_distinguished_csn == -1 && value->presence_csn > value->delete_csn)
        value->delete_csn = NOT_PRESENT;
    else if (value->delete_csn < max_val(value_distinguished_csn, value->presence_csn))
        value->delete_csn = NOT_PRESENT;
}

void
resolve_value_state(Entry_State *entry, int value_index)
{
    Value_State *value = &(entry->values[value_index]);
    int value_distinguished_csn = get_value_dn_csn(entry, value_index);

    purge_value_state(entry, value_index);

    /* no deletes that effect the state */
    if (max_val(value->delete_csn, entry->attr_delete_csn) <
        max_val(value_distinguished_csn, value->presence_csn)) {
        value->present = 1;
        return;
    }

    if (value->present) /* check if it should be removed based on the current state */
    {
        if (!value_distinguished_at_delete(entry, value_index)) {
            value->present = 0;
        }
    } else /* not present - check if it should be restored */
    {
        if (value_distinguished_at_delete(entry, value_index)) {
            value->present = 1;
        }
    }
}

int
value_distinguished_at_delete(Entry_State *entry, int value_index)
{
    Value_State *value = &(entry->values[value_index]);
    int value_distinguished_csn = get_value_dn_csn(entry, value_index);
    int delete_csn;
    int i;

    /* value has never been distinguished */
    if (value_distinguished_csn == -1)
        return 0;

    delete_csn = max_val(entry->attr_delete_csn, value->delete_csn);

    for (i = 0; i < entry->dn_csn_count; i++) {
        if (entry->dn_csns[i].csn > delete_csn)
            break;
    }

    /* i is never equal to 0 because the csn of the first element is always
       smaller than csn of any operation we can receive */
    return (entry->dn_csns[i - 1].value_index == value_index);
}

int
compare_entry_state(Entry_State *entry1, Entry_State *entry2, int run)
{
    int i;
    int error = 0;

    /* first - quick check for present / not present */
    for (i = 0; i < sim.value_count; i++) {
        if (entry1->values[i].present != entry2->values[i].present) {
            fprintf(sim.fout,
                    "value %s is %s present in the first run but %s present in the %d run\n",
                    g_values[i], entry1->values[i].present ? "" : "not",
                    entry2->values[i].present ? "" : "not", run);
            error = 1;
        }
    }

    if (error)
        return 3;

    /* compare dnc_csn list */
    if (entry1->dn_csn_count != entry2->dn_csn_count) {
        fprintf(sim.fout, "dn_csn count is %d for run 1 and %d for run %d\n",
                entry1->dn_csn_count, entry2->dn_csn_count, run);
        error = 1;
    }

    for (i = 0; i < entry1->dn_csn_count; i++) {
        if (entry1->dn_csns[i].csn != entry2->dn_csns[i].csn ||
            entry1->dn_csns[i].value_index != entry2->dn_csns[i].value_index) {
            fprintf(sim.fout, "elements %d of dn csn list are different:\n"
                              "\tfirst run: csn - %d, value - %s\n"
                              "\t%d run: csn - %d, value - %s\n",
                    i,
                    entry1->dn_csns[i].csn,
                    g_values[entry1->dn_csns[i].value_index],
                    run, entry2->dn_csns[i].csn,
                    g_values[entry2->dn_csns[i].value_index]);

            error = 1;
        }
    }

    /* compare value state */
    if (entry1->attr_delete_csn != entry2->attr_delete_csn) {
        fprintf(sim.fout, "attribute delete csn is %d for run 1 "
                          "but is %d for run %d\n",
                entry1->attr_delete_csn,
                entry2->attr_delete_csn, run);
        error = 1;
    }

    for (i = 0; i < sim.value_count; i++) {
        if (entry1->values[i].presence_csn != entry2->values[i].presence_csn) {
            fprintf(sim.fout, "presence csn for value %s is %d in run 1 "
                              "but is %d in run %d\n",
                    g_values[i], entry1->values[i].presence_csn,
                    entry2->values[i].presence_csn, run);
            error = 1;
        }

        if (entry1->values[i].distinguished_index != entry2->values[i].distinguished_index) {
            fprintf(sim.fout, "distinguished index for value %s is %d in run 1 "
                              "but is %d in run %d\n",
                    g_values[i],
                    entry1->values[i].distinguished_index,
                    entry2->values[i].distinguished_index, run);
            error = 1;
        }

        if (entry1->values[i].delete_csn != entry2->values[i].delete_csn) {
            fprintf(sim.fout, "delete csn for value %s is %d in run 1 "
                              "but is %d in run %d\n",
                    g_values[i], entry1->values[i].delete_csn,
                    entry2->values[i].delete_csn, run);
            error = 1;
        }
    }

    if (error != 0) {
        return 1;
    } else
        return 0;
}

int
dn_csn_add(Entry_State *entry, int value_index, int csn)
{
    int i, j;
    int distinguished_index;

    for (i = 0; i < entry->dn_csn_count; i++) {
        if (entry->dn_csns[i].csn > csn)
            break;
    }

    if (i < entry->dn_csn_count) {
        distinguished_index = i;
        for (j = i; j < entry->dn_csn_count; j++) {
            if (entry->dn_csns[j].value_index == value_index)
                distinguished_index = j + 1;

            if (entry->values[entry->dn_csns[j].value_index].distinguished_index == j)
                entry->values[entry->dn_csns[j].value_index].distinguished_index++;
        }

        memcpy(&(entry->dn_csns[i + 1]), &(entry->dn_csns[i]),
               (entry->dn_csn_count - i) * sizeof(Dn_Csn));
    } else {
        distinguished_index = entry->dn_csn_count;
    }

    entry->values[value_index].distinguished_index = distinguished_index;
    entry->dn_csns[i].csn = csn;
    entry->dn_csns[i].value_index = value_index;
    entry->dn_csn_count++;

    return i;
}

int
get_value_dn_csn(Entry_State *entry, int value_index)
{
    Value_State *value = &(entry->values[value_index]);

    if (value->distinguished_index == -1)
        return -1;
    else
        return entry->dn_csns[value->distinguished_index].csn;
}

void
dump_operations(Operation *ops, int op_count, int *order)
{
    int index;
    int i;

    for (i = 0; i < op_count; i++) {
        if (order == NULL) /* current order */
            index = i;
        else
            index = order[i];

        dump_operation(&ops[index]);
    }

    fprintf(sim.fout, "\n");
}

void
dump_operation(Operation *op)
{
    switch (op->type) {
    case OP_ADD_VALUE:
        fprintf(sim.fout, "\t%d add value %s\n", op->csn,
                g_values[op->value_index]);
        break;
    case OP_DELETE_VALUE:
        fprintf(sim.fout, "\t%d delete value %s\n", op->csn,
                g_values[op->value_index]);
        break;
    case OP_DELETE_ATTR:
        fprintf(sim.fout, "\t%d delete attribute\n", op->csn);
        break;
    case OP_RENAME_ENTRY:
        fprintf(sim.fout, "\t%d rename entry to %s\n", op->csn,
                g_values[op->value_index]);
        break;
    }
}

void
dump_perm_table(int **perm_table, int op_count)
{
    int i, j;
    int perm_count = get_perm_count(op_count);

    for (i = 0; i < op_count; i++) {
        for (j = 0; j < perm_count; j++) {
            fprintf(sim.fout, "%d  ", perm_table[j][i]);
        }

        fprintf(sim.fout, "\n");
    }
}

void
dump_entry_state(Entry_State *entry)
{
    int i;

    dump_dn_csn_list(entry);

    for (i = 0; i < sim.value_count; i++) {
        dump_value_state(&(entry->values[i]));
    }

    fprintf(sim.fout, "\n");
}

void
dump_value_state(Value_State *value)
{
    fprintf(sim.fout, "\tvalue %s is %s\n", g_values[value->value_index],
            value->present ? "present" : "not present");

    if (sim.verbose) {
        fprintf(sim.fout, "\t\tpresent csn: %d\n", value->presence_csn);
        fprintf(sim.fout, "\t\tdistinguished index: %d\n", value->distinguished_index);
        fprintf(sim.fout, "\t\tdelete value csn: %d\n", value->delete_csn);
    }
}

void
dump_dn_csn_list(Entry_State *entry)
{
    int i;

    fprintf(sim.fout, "\tdn csn list: \n");
    for (i = 0; i < entry->dn_csn_count; i++) {
        fprintf(sim.fout, "\t\tvalue: %s, csn: %d\n",
                g_values[entry->dn_csns[i].value_index], entry->dn_csns[i].csn);
    }
}

/* misc functions */
int
max_val(int a, int b)
{
    if (a >= b)
        return a;
    else
        return b;
}