tube.c

   1 /* tube.c - tubes implementation */
   2
   3 /* Copyright (C) 2008 Keith Rarick and Philotic Inc.
   4
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <stdlib.h>
  20 #include <string.h>
  21
  22 #include "ms.h"
  23 #include "stat.h"
  24 #include "tube.h"
  25 #include "prot.h"
  26 #include "util.h"
  27
  28 struct ms tubes;
  29
  30 tube
  31 make_tube(const char *name)
  32 {
  33     tube t;
  34
  35     t = malloc(sizeof(struct tube));
  36     if (!t) return NULL;
  37
  38     t->refs = 0;
  39
  40     t->name[MAX_TUBE_NAME_LEN - 1] = '\0';
  41     strncpy(t->name, name, MAX_TUBE_NAME_LEN - 1);
  42     if (t->name[MAX_TUBE_NAME_LEN - 1] != '\0') twarnx("truncating tube name");
  43
  44     pq_init(&t->ready, job_pri_cmp);
  45     pq_init(&t->delay, job_delay_cmp);
  46     t->buried = (struct job) { &t->buried, &t->buried, 0 };
  47     ms_init(&t->waiting, NULL, NULL);
  48
  49     t->stat = (struct stats) {0, 0, 0, 0};
  50     t->using_ct = t->watching_ct = 0;
  51
  52     return t;
  53 }
  54
  55 static void
  56 tube_free(tube t)
  57 {
  58     prot_remove_tube(t);
  59     pq_clear(&t->ready);
  60     ms_clear(&t->waiting);
  61     free(t);
  62 }
  63
  64 void
  65 tube_dref(tube t)
  66 {
  67     if (!t) return;
  68     if (t->refs < 1) return twarnx("refs is zero for tube: %s", t->name);
  69
  70     --t->refs;
  71     if (t->refs < 1) tube_free(t);
  72 }
  73
  74 void
  75 tube_iref(tube t)
  76 {
  77     if (!t) return;
  78     ++t->refs;
  79 }
  80
  81 static tube
  82 make_and_insert_tube(const char *name)
  83 {
  84     int r;
  85     tube t = NULL;
  86
  87     t = make_tube(name);
  88     if (!t) return NULL;
  89
  90     /* We want this global tube list to behave like "weak" refs, so don't
  91      * increment the ref count. */
  92     r = ms_append(&tubes, t);
  93     if (!r) return tube_dref(t), NULL;
  94
  95     return t;
  96 }
  97
  98 tube
  99 tube_find(const char *name)
 100 {
 101     tube t;
 102     size_t i;
 103
 104     for (i = 0; i < tubes.used; i++) {
 105         t = tubes.items[i];
 106         if (strncmp(t->name, name, MAX_TUBE_NAME_LEN) == 0) return t;
 107     }
 108     return NULL;
 109 }
 110
 111 tube
 112 tube_find_or_make(const char *name)
 113 {
 114     return tube_find(name) ? : make_and_insert_tube(name);
 115 }
 116