service: make instance_update() void and unconditionally replace config on update

[project/procd.git] / service / instance.c

diff --git a/service/instance.c b/service/instance.c
index f2604fe..bfc0979 100644 (file)
--- a/service/instance.c
+++ b/service/instance.c
@@ -53,6 +53,7 @@ enum {
        INSTANCE_ATTR_JAIL,
        INSTANCE_ATTR_TRACE,
        INSTANCE_ATTR_SECCOMP,
+       INSTANCE_ATTR_PIDFILE,
        __INSTANCE_ATTR_MAX
 };
 
@@ -75,6 +76,7 @@ static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
        [INSTANCE_ATTR_JAIL] = { "jail", BLOBMSG_TYPE_TABLE },
        [INSTANCE_ATTR_TRACE] = { "trace", BLOBMSG_TYPE_BOOL },
        [INSTANCE_ATTR_SECCOMP] = { "seccomp", BLOBMSG_TYPE_STRING },
+       [INSTANCE_ATTR_PIDFILE] = { "pidfile", BLOBMSG_TYPE_STRING },
 };
 
 enum {
@@ -232,6 +234,46 @@ jail_run(struct service_instance *in, char **argv)
        return argc;
 }
 
+static int
+instance_removepid(struct service_instance *in) {
+       if (!in->pidfile)
+               return 0;
+       if (unlink(in->pidfile)) {
+               ERROR("Failed to removed pidfile: %s: %d - %s\n",
+                       in->pidfile, errno, strerror(errno));
+               return 1;
+       }
+       return 0;
+}
+
+static int
+instance_writepid(struct service_instance *in)
+{
+       FILE *_pidfile;
+
+       if (!in->pidfile) {
+               return 0;
+       }
+       _pidfile = fopen(in->pidfile, "w");
+       if (_pidfile == NULL) {
+               ERROR("failed to open pidfile for writing: %s: %d (%s)",
+                       in->pidfile, errno, strerror(errno));
+               return 1;
+       }
+       if (fprintf(_pidfile, "%d\n", in->proc.pid) < 0) {
+               ERROR("failed to write pidfile: %s: %d (%s)",
+                       in->pidfile, errno, strerror(errno));
+               return 2;
+       }
+       if (fclose(_pidfile)) {
+               ERROR("failed to close pidfile: %s: %d (%s)",
+                       in->pidfile, errno, strerror(errno));
+               return 3;
+       }
+
+       return 0;
+}
+
 static void
 instance_run(struct service_instance *in, int _stdout, int _stderr)
 {
@@ -344,7 +386,7 @@ instance_start(struct service_instance *in)
                return;
        }
 
-       if (in->proc.pending)
+       if (in->proc.pending || !in->command)
                return;
 
        instance_free_stdio(in);
@@ -380,8 +422,9 @@ instance_start(struct service_instance *in)
                return;
        }
 
-       DEBUG(2, "Started instance %s::%s\n", in->srv->name, in->name);
+       DEBUG(2, "Started instance %s::%s[%d]\n", in->srv->name, in->name, pid);
        in->proc.pid = pid;
+       instance_writepid(in);
        clock_gettime(CLOCK_MONOTONIC, &in->start);
        uloop_process_add(&in->proc);
 
@@ -470,7 +513,7 @@ instance_exit(struct uloop_process *p, int ret)
 
        uloop_timeout_cancel(&in->timeout);
        if (in->halt) {
-               /* no action */
+               instance_removepid(in);
        } else if (in->restart) {
                instance_start(in);
        } else if (in->respawn) {
@@ -483,7 +526,9 @@ instance_exit(struct uloop_process *p, int ret)
                                                                in->srv->name, in->name, in->respawn_count, runtime);
                        in->restart = in->respawn = 0;
                        in->halt = 1;
+                       service_event("instance.fail", in->srv->name, in->name);
                } else {
+                       service_event("instance.respawn", in->srv->name, in->name);
                        uloop_timeout_set(&in->timeout, in->respawn_timeout * 1000);
                }
        }
@@ -508,6 +553,7 @@ instance_restart(struct service_instance *in)
        in->halt = false;
        in->restart = true;
        kill(in->proc.pid, SIGTERM);
+       instance_removepid(in);
 }
 
 static bool
@@ -540,6 +586,16 @@ instance_config_changed(struct service_instance *in, struct service_instance *in
        if (in->gid != in_new->gid)
                return true;
 
+       if (in->pidfile && in_new->pidfile)
+               if (strcmp(in->pidfile, in_new->pidfile))
+                       return true;
+
+       if (in->pidfile && !in_new->pidfile)
+               return true;
+
+       if (!in->pidfile && in_new->pidfile)
+               return true;
+
        if (!blobmsg_list_equal(&in->limits, &in_new->limits))
                return true;
 
@@ -697,31 +753,42 @@ instance_jail_parse(struct service_instance *in, struct blob_attr *attr)
 }
 
 static bool
-instance_config_parse(struct service_instance *in)
+instance_config_parse_command(struct service_instance *in, struct blob_attr **tb)
 {
-       struct blob_attr *tb[__INSTANCE_ATTR_MAX];
        struct blob_attr *cur, *cur2;
-       int argc = 0;
+       bool ret = false;
        int rem;
 
-       blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
-               blobmsg_data(in->config), blobmsg_data_len(in->config));
-
        cur = tb[INSTANCE_ATTR_COMMAND];
-       if (!cur)
-               return false;
+       if (!cur) {
+               in->command = NULL;
+               return true;
+       }
 
        if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
                return false;
 
        blobmsg_for_each_attr(cur2, cur, rem) {
-               argc++;
+               ret = true;
                break;
        }
-       if (!argc)
-               return false;
 
        in->command = cur;
+       return ret;
+}
+
+static bool
+instance_config_parse(struct service_instance *in)
+{
+       struct blob_attr *tb[__INSTANCE_ATTR_MAX];
+       struct blob_attr *cur, *cur2;
+       int rem;
+
+       blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
+               blobmsg_data(in->config), blobmsg_data_len(in->config));
+
+       if (!instance_config_parse_command(in, tb))
+               return false;
 
        if (tb[INSTANCE_ATTR_RESPAWN]) {
                int i = 0;
@@ -782,6 +849,13 @@ instance_config_parse(struct service_instance *in)
                else
                        in->seccomp = seccomp;
        }
+
+       if (tb[INSTANCE_ATTR_PIDFILE]) {
+               char *pidfile = blobmsg_get_string(tb[INSTANCE_ATTR_PIDFILE]);
+               if (pidfile)
+                       in->pidfile = pidfile;
+       }
+
        if (!in->trace && tb[INSTANCE_ATTR_JAIL])
                in->has_jail = instance_jail_parse(in, tb[INSTANCE_ATTR_JAIL]);
 
@@ -836,6 +910,7 @@ instance_config_move(struct service_instance *in, struct service_instance *in_sr
        blobmsg_list_move(&in->jail.mount, &in_src->jail.mount);
        in->trigger = in_src->trigger;
        in->command = in_src->command;
+       in->pidfile = in_src->pidfile;
        in->name = in_src->name;
        in->node.avl.key = in_src->node.avl.key;
 
@@ -844,25 +919,21 @@ instance_config_move(struct service_instance *in, struct service_instance *in_sr
        in_src->config = NULL;
 }
 
-bool
+void
 instance_update(struct service_instance *in, struct service_instance *in_new)
 {
        bool changed = instance_config_changed(in, in_new);
        bool running = in->proc.pending;
 
-       if (!changed && running)
-               return false;
-
        if (!running) {
-               if (changed)
-                       instance_config_move(in, in_new);
+               instance_config_move(in, in_new);
                instance_start(in);
        } else {
-               instance_restart(in);
+               if (changed)
+                       instance_restart(in);
                instance_config_move(in, in_new);
                /* restart happens in the child callback handler */
        }
-       return true;
 }
 
 void
@@ -917,7 +988,8 @@ void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
        blobmsg_add_u8(b, "running", in->proc.pending);
        if (in->proc.pending)
                blobmsg_add_u32(b, "pid", in->proc.pid);
-       blobmsg_add_blob(b, in->command);
+       if (in->command)
+               blobmsg_add_blob(b, in->command);
 
        if (!avl_is_empty(&in->errors.avl)) {
                struct blobmsg_list_node *var;
@@ -968,6 +1040,9 @@ void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
        if (in->seccomp)
                blobmsg_add_string(b, "seccomp", in->seccomp);
 
+       if (in->pidfile)
+               blobmsg_add_string(b, "pidfile", in->pidfile);
+
        if (in->has_jail) {
                void *r = blobmsg_open_table(b, "jail");
                if (in->jail.name)