source: vendor/current/ctdb/common/reqid.c

/*
   ctdb request id handling code

   Copyright (C) Amitay Isaacs  2015

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

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

#include "replace.h"

#include <talloc.h>

#include "lib/util/idtree.h"
#include "reqid.h"

struct reqid_context {
        struct idr_context *idr;
        uint32_t lastid;
};

int reqid_init(TALLOC_CTX *mem_ctx, int start_id,
               struct reqid_context **result)
{
        struct reqid_context *reqid_ctx;

        reqid_ctx = talloc_zero(mem_ctx, struct reqid_context);
        if (reqid_ctx == NULL) {
                return ENOMEM;
        }

        reqid_ctx->idr = idr_init(reqid_ctx);
        if (reqid_ctx->idr == NULL) {
                talloc_free(reqid_ctx);
                return ENOMEM;
        }

        if (start_id <= 0) {
                start_id = 1;
        }
        reqid_ctx->lastid = start_id;

        *result = reqid_ctx;
        return 0;
}

uint32_t reqid_new(struct reqid_context *reqid_ctx, void *private_data)
{
        int id;

        id = idr_get_new_above(reqid_ctx->idr, private_data,
                               reqid_ctx->lastid+1, INT_MAX);
        if (id < 0) {
                /* reqid wrapped */
                id = idr_get_new(reqid_ctx->idr, private_data, INT_MAX);
        }
        if (id == -1) {
                return REQID_INVALID;
        }

        reqid_ctx->lastid = id;
        return id;
}

void *_reqid_find(struct reqid_context *reqid_ctx, uint32_t reqid)
{
        return idr_find(reqid_ctx->idr, reqid);
}

int reqid_remove(struct reqid_context *reqid_ctx, uint32_t reqid)
{
        int ret;

        ret = idr_remove(reqid_ctx->idr, reqid);
        if (ret < 0) {
                return ENOENT;
        }
        return 0;
}