job.c

   1 /* job.c - a job in the queue */
   2
   3 #include <stdlib.h>
   4 #include <string.h>
   5
   6 #include "job.h"
   7 #include "util.h"
   8
   9 static unsigned long long int next_id = 1;
  10
  11 job
  12 allocate_job(int body_size)
  13 {
  14     job j;
  15
  16     j = malloc(sizeof(struct job) + body_size);
  17     if (!j) return twarnx("OOM"), NULL;
  18
  19     j->state = JOB_STATE_INVALID;
  20     j->creation = time(NULL);
  21     j->timeout_ct = j->release_ct = j->bury_ct = j->kick_ct = 0;
  22     j->body_size = body_size;
  23     j->next = j->prev = j; /* not in a linked list */
  24
  25     return j;
  26 }
  27
  28 job
  29 make_job(unsigned int pri, unsigned int delay, int body_size)
  30 {
  31     job j;
  32
  33     j = allocate_job(body_size);
  34     if (!j) return twarnx("OOM"), NULL;
  35
  36     j->id = next_id++;
  37     j->pri = pri;
  38     j->delay = delay;
  39
  40     return j;
  41 }
  42
  43 int
  44 job_pri_cmp(job a, job b)
  45 {
  46     if (a->pri == b->pri) {
  47         /* we can't just subtract because id has too many bits */
  48         if (a->id > b->id) return 1;
  49         if (a->id < b->id) return -1;
  50         return 0;
  51     }
  52     return a->pri - b->pri;
  53 }
  54
  55 int
  56 job_delay_cmp(job a, job b)
  57 {
  58     if (a->deadline == b->deadline) {
  59         /* we can't just subtract because id has too many bits */
  60         if (a->id > b->id) return 1;
  61         if (a->id < b->id) return -1;
  62         return 0;
  63     }
  64     return a->deadline - b->deadline;
  65 }
  66
  67 job
  68 job_copy(job j)
  69 {
  70     job n;
  71
  72     if (!j) return NULL;
  73
  74     n = malloc(sizeof(struct job) + j->body_size);
  75     if (!n) return twarnx("OOM"), NULL;
  76
  77     n->id = j->id;
  78     n->pri = j->pri;
  79     n->body_size = j->body_size;
  80     memcpy(n->body, j->body, j->body_size);
  81
  82     return n;
  83 }
  84
  85 const char *
  86 job_state(job j)
  87 {
  88     if (j->state == JOB_STATE_READY) return "ready";
  89     if (j->state == JOB_STATE_RESERVED) return "reserved";
  90     if (j->state == JOB_STATE_BURIED) return "buried";
  91     if (j->state == JOB_STATE_DELAY) return "delay";
  92     return "invalid";
  93 }
  94
  95 int
  96 job_list_any_p(job head)
  97 {
  98     return head->next != head || head->prev != head;
  99 }
 100
 101 job
 102 job_remove(job j)
 103 {
 104     if (!j) return NULL;
 105     if (!job_list_any_p(j)) return NULL; /* not in a doubly-linked list */
 106
 107     j->next->prev = j->prev;
 108     j->prev->next = j->next;
 109
 110     j->prev = j->next = j;
 111
 112     return j;
 113 }
 114
 115 void
 116 job_insert(job head, job j)
 117 {
 118     if (job_list_any_p(j)) return; /* already in a linked list */
 119
 120     j->prev = head->prev;
 121     j->next = head;
 122     head->prev->next = j;
 123     head->prev = j;
 124 }
 125
 126 unsigned long long int
 127 total_jobs()
 128 {
 129     return next_id - 1;
 130 }