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) { };
  47     t->buried.prev = t->buried.next = &t->buried;
  48     ms_init(&t->waiting, NULL, NULL);
  49
  50     t->stat = (struct stats) {0, 0, 0, 0};
  51     t->using_ct = t->watching_ct = 0;
  52
  53     return t;
  54 }
  55
  56 static void
  57 tube_free(tube t)
  58 {
  59     prot_remove_tube(t);
  60     pq_clear(&t->ready);
  61     pq_clear(&t->delay);
  62     ms_clear(&t->waiting);
  63     free(t);
  64 }
  65
  66 void
  67 tube_dref(tube t)
  68 {
  69     if (!t) return;
  70     if (t->refs < 1) return twarnx("refs is zero for tube: %s", t->name);
  71
  72     --t->refs;
  73     if (t->refs < 1) tube_free(t);
  74 }
  75
  76 void
  77 tube_iref(tube t)
  78 {
  79     if (!t) return;
  80     ++t->refs;
  81 }
  82
  83 static tube
  84 make_and_insert_tube(const char *name)
  85 {
  86     int r;
  87     tube t = NULL;
  88
  89     t = make_tube(name);
  90     if (!t) return NULL;
  91
  92     /* We want this global tube list to behave like "weak" refs, so don't
  93      * increment the ref count. */
  94     r = ms_append(&tubes, t);
  95     if (!r) return tube_dref(t), (tube) 0;
  96
  97     return t;
  98 }
  99
 100 tube
 101 tube_find(const char *name)
 102 {
 103     tube t;
 104     size_t i;
 105
 106     for (i = 0; i < tubes.used; i++) {
 107         t = tubes.items[i];
 108         if (strncmp(t->name, name, MAX_TUBE_NAME_LEN) == 0) return t;
 109     }
 110     return NULL;
 111 }
 112
 113 tube
 114 tube_find_or_make(const char *name)
 115 {
 116     return tube_find(name) ? : make_and_insert_tube(name);
 117 }
 118