ctdb/common/reqid.c

   1 /*
   2    ctdb request id handling code
   3
   4    Copyright (C) Amitay Isaacs  2015
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "replace.h"
  21
  22 #include <talloc.h>
  23
  24 #include "lib/util/idtree.h"
  25 #include "reqid.h"
  26
  27 struct reqid_context {
  28         struct idr_context *idr;
  29         uint32_t lastid;
  30 };
  31
  32 int reqid_init(TALLOC_CTX *mem_ctx, int start_id,
  33                struct reqid_context **result)
  34 {
  35         struct reqid_context *reqid_ctx;
  36
  37         reqid_ctx = talloc_zero(mem_ctx, struct reqid_context);
  38         if (reqid_ctx == NULL) {
  39                 return ENOMEM;
  40         }
  41
  42         reqid_ctx->idr = idr_init(reqid_ctx);
  43         if (reqid_ctx->idr == NULL) {
  44                 talloc_free(reqid_ctx);
  45                 return ENOMEM;
  46         }
  47
  48         if (start_id <= 0) {
  49                 start_id = 1;
  50         }
  51         reqid_ctx->lastid = start_id;
  52
  53         *result = reqid_ctx;
  54         return 0;
  55 }
  56
  57 uint32_t reqid_new(struct reqid_context *reqid_ctx, void *private_data)
  58 {
  59         int id;
  60
  61         id = idr_get_new_above(reqid_ctx->idr, private_data,
  62                                reqid_ctx->lastid+1, INT_MAX);
  63         if (id < 0) {
  64                 /* reqid wrapped */
  65                 id = idr_get_new(reqid_ctx->idr, private_data, INT_MAX);
  66         }
  67         if (id == -1) {
  68                 return REQID_INVALID;
  69         }
  70
  71         reqid_ctx->lastid = id;
  72         return id;
  73 }
  74
  75 void *_reqid_find(struct reqid_context *reqid_ctx, uint32_t reqid)
  76 {
  77         return idr_find(reqid_ctx->idr, reqid);
  78 }
  79
  80 int reqid_remove(struct reqid_context *reqid_ctx, uint32_t reqid)
  81 {
  82         int ret;
  83
  84         ret = idr_remove(reqid_ctx->idr, reqid);
  85         if (ret < 0) {
  86                 return ENOENT;
  87         }
  88         return 0;
  89 }