instance.c

   1 #include <unistd.h>
   2
   3 #include "procd.h"
   4 #include "service.h"
   5 #include "instance.h"
   6
   7 enum {
   8         INSTANCE_ATTR_COMMAND,
   9         INSTANCE_ATTR_ENV,
  10         INSTANCE_ATTR_DATA,
  11         __INSTANCE_ATTR_MAX
  12 };
  13
  14 static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
  15         [INSTANCE_ATTR_COMMAND] = { "command", BLOBMSG_TYPE_ARRAY },
  16         [INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
  17         [INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
  18 };
  19
  20 static void
  21 instance_run(struct service_instance *in)
  22 {
  23         struct blobmsg_list_node *var;
  24         struct blob_attr *cur;
  25         char **argv;
  26         int argc = 1; /* NULL terminated */
  27         int rem;
  28
  29         blobmsg_for_each_attr(cur, in->command, rem)
  30                 argc++;
  31
  32         blobmsg_list_for_each(&in->env, var)
  33                 putenv(blobmsg_data(var->data));
  34
  35         argv = alloca(sizeof(char *) * argc);
  36         argc = 0;
  37
  38         blobmsg_for_each_attr(cur, in->command, rem)
  39                 argv[argc++] = blobmsg_data(cur);
  40
  41         argv[argc] = NULL;
  42         execvp(argv[0], argv);
  43         exit(127);
  44 }
  45
  46 void
  47 instance_start(struct service_instance *in)
  48 {
  49         int pid;
  50
  51         if (in->proc.pending)
  52                 return;
  53
  54         in->restart = false;
  55         if (!in->valid)
  56                 return;
  57
  58         pid = fork();
  59         if (pid < 0)
  60                 return;
  61
  62         if (!pid) {
  63                 instance_run(in);
  64                 return;
  65         }
  66
  67         DPRINTF("Started instance %s::%s\n", in->srv->name, in->name);
  68         in->proc.pid = pid;
  69         uloop_process_add(&in->proc);
  70 }
  71
  72 static void
  73 instance_timeout(struct uloop_timeout *t)
  74 {
  75         struct service_instance *in;
  76
  77         in = container_of(t, struct service_instance, timeout);
  78         kill(in->proc.pid, SIGKILL);
  79         uloop_process_delete(&in->proc);
  80         in->proc.cb(&in->proc, -1);
  81 }
  82
  83 static void
  84 instance_exit(struct uloop_process *p, int ret)
  85 {
  86         struct service_instance *in;
  87
  88         in = container_of(p, struct service_instance, proc);
  89         uloop_timeout_cancel(&in->timeout);
  90         if (in->restart)
  91                 instance_start(in);
  92 }
  93
  94 void
  95 instance_stop(struct service_instance *in, bool restart)
  96 {
  97         if (!in->proc.pending)
  98                 return;
  99
 100         kill(in->proc.pid, SIGTERM);
 101 }
 102
 103 static bool
 104 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 105 {
 106         if (!in->valid)
 107                 return true;
 108
 109         if (!blob_attr_equal(in->command, in_new->command))
 110                 return true;
 111
 112         if (!blobmsg_list_equal(&in->env, &in_new->env))
 113                 return true;
 114
 115         if (!blobmsg_list_equal(&in->data, &in_new->data))
 116                 return true;
 117
 118         return false;
 119 }
 120
 121 static bool
 122 instance_config_parse(struct service_instance *in)
 123 {
 124         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 125         struct blob_attr *cur, *cur2;
 126         int argc = 0;
 127         int rem;
 128
 129         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 130                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 131
 132         cur = tb[INSTANCE_ATTR_COMMAND];
 133         if (!cur)
 134                 return false;
 135
 136         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 137                 return false;
 138
 139         blobmsg_for_each_attr(cur2, cur, rem) {
 140                 argc++;
 141                 break;
 142         }
 143         if (!argc)
 144                 return false;
 145
 146         in->command = cur;
 147
 148         if ((cur = tb[INSTANCE_ATTR_ENV])) {
 149                 if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 150                         return false;
 151                 blobmsg_list_fill(&in->env, blobmsg_data(cur), blobmsg_data_len(cur));
 152         }
 153
 154         if ((cur = tb[INSTANCE_ATTR_DATA])) {
 155                 if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 156                         return false;
 157                 blobmsg_list_fill(&in->data, blobmsg_data(cur), blobmsg_data_len(cur));
 158         }
 159
 160         return true;
 161 }
 162
 163 static void
 164 instance_config_cleanup(struct service_instance *in)
 165 {
 166         blobmsg_list_free(&in->env);
 167         blobmsg_list_free(&in->data);
 168 }
 169
 170 static void
 171 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 172 {
 173         instance_config_cleanup(in);
 174         blobmsg_list_move(&in->env, &in_src->env);
 175         blobmsg_list_move(&in->data, &in_src->data);
 176         in->command = in_src->command;
 177         in->name = in_src->name;
 178 }
 179
 180 bool
 181 instance_update(struct service_instance *in, struct service_instance *in_new)
 182 {
 183         bool changed = instance_config_changed(in, in_new);
 184
 185         in->config = in_new->config;
 186         if (!changed)
 187                 return false;
 188
 189         in->restart = true;
 190         instance_stop(in, true);
 191         instance_config_move(in, in_new);
 192         return true;
 193 }
 194
 195 void
 196 instance_free(struct service_instance *in)
 197 {
 198         uloop_process_delete(&in->proc);
 199         uloop_timeout_cancel(&in->timeout);
 200         instance_config_cleanup(in);
 201         free(in);
 202 }
 203
 204 void
 205 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 206 {
 207         in->srv = s;
 208         in->name = blobmsg_name(config);
 209         in->config = config;
 210         in->timeout.cb = instance_timeout;
 211         in->proc.cb = instance_exit;
 212
 213         blobmsg_list_simple_init(&in->env);
 214         blobmsg_list_simple_init(&in->data);
 215         in->valid = instance_config_parse(in);
 216 }
 217
 218 void instance_dump(struct blob_buf *b, struct service_instance *in)
 219 {
 220         void *i;
 221
 222         i = blobmsg_open_table(b, in->name);
 223         blobmsg_add_u8(b, "running", in->proc.pending);
 224         if (in->proc.pending)
 225                 blobmsg_add_u32(b, "pid", in->proc.pid);
 226         blobmsg_add_blob(b, in->command);
 227         blobmsg_close_table(b, i);
 228 }