From: José Bollo <jose.bollo@iot.bzh>
Date: Tue, 15 Mar 2016 09:28:33 +0000 (+0100)
Subject: afm-run: improvement and comments
X-Git-Tag: 2.0.2~41
X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=commitdiff_plain;h=f4f91abe09bd0d3a4bc9bc06b073f1acbd374786;p=src%2Fapp-framework-main.git
afm-run: improvement and comments
Change-Id: I7eee1d6033e645269fe89d17dd9d75c063ed4551
Signed-off-by: José Bollo <jose.bollo@iot.bzh>
---
diff --git a/src/afm-launch-mode.h b/src/afm-launch-mode.h
index 8eee8eb..4b840ab 100644
--- a/src/afm-launch-mode.h
+++ b/src/afm-launch-mode.h
@@ -25,6 +25,7 @@ enum afm_launch_mode {
#define default_launch_mode mode_local
#define launch_mode_is_valid(x) ((x)==mode_local || (x)==mode_remote)
+#define is_valid_launch_mode(x) ((x)==mode_local || (x)==mode_remote)
enum afm_launch_mode launch_mode_of_string(const char *s);
const char *name_of_launch_mode(enum afm_launch_mode m);
diff --git a/src/afm-run.c b/src/afm-run.c
index 915230d..91e2a0b 100644
--- a/src/afm-run.c
+++ b/src/afm-run.c
@@ -36,72 +36,128 @@
#include "afm-launch.h"
#include "afm-run.h"
+/*
+ * State of a launched/running application
+ */
enum appstate {
- as_starting,
- as_running,
- as_stopped,
- as_terminating,
- as_terminated
+ as_starting, /* start in progress */
+ as_running, /* started and running */
+ as_stopped, /* stopped */
+ as_terminating, /* termination in progress */
+ as_terminated /* terminated */
};
+/*
+ * Structure for recording a runner
+ */
struct apprun {
- struct apprun *next_by_runid;
- struct apprun *next_by_pgid;
- int runid;
- pid_t pids[2]; /* 0: group leader, 1: slave (appli) */
- enum appstate state;
- json_object *appli;
+ struct apprun *next_by_runid; /* link for hashing by runid */
+ struct apprun *next_by_pgid; /* link for hashing by pgid */
+ int runid; /* runid */
+ pid_t pids[2]; /* pids (0: group leader, 1: slave) */
+ enum appstate state; /* current state of the application */
+ json_object *appli; /* json object describing the application */
};
+/*
+ * Count of item by hash table
+ */
#define ROOT_RUNNERS_COUNT 32
+
+/*
+ * Maximum count of simultaneous running application
+ */
#define MAX_RUNNER_COUNT 32767
+/*
+ * Hash tables of runners by runid and by pgid
+ */
static struct apprun *runners_by_runid[ROOT_RUNNERS_COUNT];
static struct apprun *runners_by_pgid[ROOT_RUNNERS_COUNT];
+
+/*
+ * List of terminated runners
+ */
+static struct apprun *terminated_runners = NULL;
+
+/*
+ * Count of runners
+ */
static int runnercount = 0;
+
+/*
+ * Last given runid
+ */
static int runnerid = 0;
+/*
+ * Path name of the directory for applications in the
+ * home directory of the user.
+ */
static const char fwk_user_app_dir[] = FWK_USER_APP_DIR;
+
+/*
+ * Path of the root directory for applications of the
+ * current user
+ */
static char *homeappdir;
/****************** manages pids **********************/
-/* get a runner by its pid */
+/*
+ * Get a runner by its 'pid' (NULL if not found)
+ */
static struct apprun *runner_of_pid(pid_t pid)
{
int i;
struct apprun *result;
- for (i = 0 ; i < ROOT_RUNNERS_COUNT ; i++)
- for (result = runners_by_pgid[i] ; result != NULL ; result = result->next_by_pgid)
+ for (i = 0 ; i < ROOT_RUNNERS_COUNT ; i++) {
+ result = runners_by_pgid[i];
+ while (result != NULL) {
if (result->pids[0] == pid || result->pids[1] == pid)
return result;
+ result = result->next_by_pgid;
+ }
+ }
return NULL;
}
/****************** manages pgids **********************/
-/* get a runner by its pgid */
+/*
+ * Get a runner by its 'pgid' (NULL if not found)
+ */
static struct apprun *runner_of_pgid(pid_t pgid)
{
- struct apprun *result = runners_by_pgid[(int)(pgid & (ROOT_RUNNERS_COUNT - 1))];
+ struct apprun *result;
+
+ result = runners_by_pgid[pgid & (ROOT_RUNNERS_COUNT - 1)];
while (result && result->pids[0] != pgid)
result = result->next_by_pgid;
return result;
}
-/* insert a runner for its pgid */
+/*
+ * Insert a 'runner' for its pgid
+ */
static void pgid_insert(struct apprun *runner)
{
- struct apprun **prev = &runners_by_pgid[(int)(runner->pids[0] & (ROOT_RUNNERS_COUNT - 1))];
+ struct apprun **prev;
+
+ prev = &runners_by_pgid[runner->pids[0] & (ROOT_RUNNERS_COUNT - 1)];
runner->next_by_pgid = *prev;
*prev = runner;
}
-/* remove a runner for its pgid */
+/*
+ * Remove a 'runner' for its pgid
+ */
static void pgid_remove(struct apprun *runner)
{
- struct apprun **prev = &runners_by_pgid[(int)(runner->pids[0] & (ROOT_RUNNERS_COUNT - 1))];
+ struct apprun **prev;
+
+ prev = &runners_by_pgid[runner->pids[0] & (ROOT_RUNNERS_COUNT - 1)];
while (*prev) {
if (*prev == runner) {
*prev = runner->next_by_pgid;
@@ -113,36 +169,71 @@ static void pgid_remove(struct apprun *runner)
/****************** manages runners (by runid) **********************/
-/* get a runner by its runid */
+/*
+ * Get a runner by its 'runid' (NULL if not found)
+ */
static struct apprun *getrunner(int runid)
{
- struct apprun *result = runners_by_runid[runid & (ROOT_RUNNERS_COUNT - 1)];
+ struct apprun *result;
+
+ result = runners_by_runid[runid & (ROOT_RUNNERS_COUNT - 1)];
while (result && result->runid != runid)
result = result->next_by_runid;
return result;
}
-/* free an existing runner */
+/*
+ * Free an existing 'runner'
+ */
static void freerunner(struct apprun *runner)
{
- struct apprun **prev = &runners_by_runid[runner->runid & (ROOT_RUNNERS_COUNT - 1)];
+ struct apprun **prev;
+
+ /* get previous pointer to runner */
+ prev = &runners_by_runid[runner->runid & (ROOT_RUNNERS_COUNT - 1)];
assert(*prev);
while(*prev != runner) {
prev = &(*prev)->next_by_runid;
assert(*prev);
}
+
+ /* unlink */
*prev = runner->next_by_runid;
+ runnercount--;
+
+ /* release/free */
json_object_put(runner->appli);
free(runner);
- runnercount--;
}
-/* create a new runner */
+/*
+ * Cleans the list of runners from its terminated
+ */
+static void cleanrunners()
+{
+ struct apprun *runner;
+ while (terminated_runners) {
+ runner = terminated_runners;
+ terminated_runners = runner->next_by_pgid;
+ freerunner(runner);
+ }
+}
+
+/*
+ * Create a new runner for the 'appli'
+ *
+ * Returns the created runner or NULL
+ * in case of error.
+ */
static struct apprun *createrunner(json_object *appli)
{
struct apprun *result;
struct apprun **prev;
+ /* cleanup */
+ cleanrunners();
+
+ /* get a runid */
if (runnercount >= MAX_RUNNER_COUNT) {
errno = EAGAIN;
return NULL;
@@ -152,10 +243,13 @@ static struct apprun *createrunner(json_object *appli)
if (runnerid > MAX_RUNNER_COUNT)
runnerid = 1;
} while(getrunner(runnerid));
+
+ /* create the structure */
result = calloc(1, sizeof * result);
if (result == NULL)
errno = ENOMEM;
else {
+ /* initialize it linked to the list */
prev = &runners_by_runid[runnerid & (ROOT_RUNNERS_COUNT - 1)];
result->next_by_runid = *prev;
result->next_by_pgid = NULL;
@@ -193,6 +287,16 @@ static void removed(int runid)
#endif
/**************** running ************************/
+/*
+ * Sends (with pgkill) the signal 'sig' to the process group
+ * for 'runid' and put the runner's state to 'tostate'
+ * in case of success.
+ *
+ * Only processes in the state 'as_running' or 'as_stopped'
+ * can be signalled.
+ *
+ * Returns 0 in case of success or -1 in case of error.
+ */
static int killrunner(int runid, int sig, enum appstate tostate)
{
int rc;
@@ -202,7 +306,7 @@ static int killrunner(int runid, int sig, enum appstate tostate)
rc = -1;
}
else if (runner->state != as_running && runner->state != as_stopped) {
- errno = EPERM;
+ errno = EINVAL;
rc = -1;
}
else if (runner->state == tostate) {
@@ -216,29 +320,41 @@ static int killrunner(int runid, int sig, enum appstate tostate)
return rc;
}
+/*
+ * Signal callback called on SIGCHLD. This is set using sigaction.
+ */
static void on_sigchld(int signum, siginfo_t *info, void *uctxt)
{
struct apprun *runner;
+ /* retrieves the runner */
runner = runner_of_pid(info->si_pid);
if (!runner)
return;
+ /* known runner, inspect cause of signal */
switch(info->si_code) {
case CLD_EXITED:
case CLD_KILLED:
case CLD_DUMPED:
case CLD_TRAPPED:
+ /* update the state */
runner->state = as_terminated;
+ /* remove it from pgid list */
pgid_remove(runner);
+ runner->next_by_pgid = terminated_runners;
+ terminated_runners = runner;
+ /* ensures that all the group stops */
killpg(runner->pids[0], SIGKILL);
break;
case CLD_STOPPED:
+ /* update the state */
runner->state = as_stopped;
break;
case CLD_CONTINUED:
+ /* update the state */
runner->state = as_running;
break;
}
@@ -246,16 +362,23 @@ static void on_sigchld(int signum, siginfo_t *info, void *uctxt)
/**************** handle afm_launch_desc *********************/
-static int fill_launch_desc(struct json_object *appli, enum afm_launch_mode mode, struct afm_launch_desc *desc)
+/*
+ * Initialize the data of the launch description 'desc'
+ * for the application 'appli' and the 'mode'.
+ *
+ * Returns 0 in case of success or -1 in case of error.
+ */
+static int fill_launch_desc(struct json_object *appli,
+ enum afm_launch_mode mode, struct afm_launch_desc *desc)
{
json_object *pub;
- assert(launch_mode_is_valid(mode));
+ assert(is_valid_launch_mode(mode));
/* main items */
if(!j_read_object_at(appli, "public", &pub)
|| !j_read_string_at(appli, "path", &desc->path)
- || !j_read_string_at(appli, "id", &desc->tag)
+ || !j_read_string_at(appli, "id", &desc->appid)
|| !j_read_string_at(appli, "content", &desc->content)
|| !j_read_string_at(appli, "type", &desc->type)
|| !j_read_string_at(pub, "name", &desc->name)
@@ -278,16 +401,85 @@ static int fill_launch_desc(struct json_object *appli, enum afm_launch_mode mode
return 0;
};
+/**************** report state of runner *********************/
+
+/*
+ * Creates a json object that describes the state of 'runner'.
+ *
+ * Returns the created object or NULL in case of error.
+ */
+static json_object *mkstate(struct apprun *runner)
+{
+ const char *state;
+ struct json_object *result, *obj;
+ int rc;
+
+ /* the structure */
+ result = json_object_new_object();
+ if (result == NULL)
+ goto error;
+
+ /* the runid */
+ if (!j_add_integer(result, "runid", runner->runid))
+ goto error2;
+
+ /* the state */
+ switch(runner->state) {
+ case as_starting:
+ case as_running:
+ state = "running";
+ break;
+ case as_stopped:
+ state = "stopped";
+ break;
+ default:
+ state = "terminated";
+ break;
+ }
+ if (!j_add_string(result, "state", state))
+ goto error2;
+
+ /* the application id */
+ rc = json_object_object_get_ex(runner->appli, "public", &obj);
+ assert(rc);
+ rc = json_object_object_get_ex(obj, "id", &obj);
+ assert(rc);
+ if (!j_add(result, "id", obj))
+ goto error2;
+ json_object_get(obj);
+
+ /* done */
+ return result;
+
+error2:
+ json_object_put(result);
+error:
+ errno = ENOMEM;
+ return NULL;
+}
+
/**************** API handling ************************/
-int afm_run_start(struct json_object *appli, enum afm_launch_mode mode, char **uri)
+/*
+ * Starts the application described by 'appli' for the 'mode'.
+ * In case of remote start, it returns in uri the uri to
+ * connect to.
+ *
+ * A reference to 'appli' is kept during the live of the
+ * runner. This is made using json_object_get. Thus be aware
+ * that further modifications to 'appli' might create errors.
+ *
+ * Returns 0 in case of success or -1 in case of error
+ */
+int afm_run_start(struct json_object *appli, enum afm_launch_mode mode,
+ char **uri)
{
static struct apprun *runner;
struct afm_launch_desc desc;
int rc;
sigset_t saved, blocked;
- assert(launch_mode_is_valid(mode));
+ assert(is_valid_launch_mode(mode));
assert(mode == mode_local || uri != NULL);
assert(uri == NULL || *uri == NULL);
@@ -324,71 +516,41 @@ int afm_run_start(struct json_object *appli, enum afm_launch_mode mode, char **u
return rc;
}
+/*
+ * Terminates the runner of 'runid'
+ *
+ * Returns 0 in case of success or -1 in case of error
+ */
int afm_run_terminate(int runid)
{
return killrunner(runid, SIGTERM, as_terminating);
}
+/*
+ * Stops (aka pause) the runner of 'runid'
+ *
+ * Returns 0 in case of success or -1 in case of error
+ */
int afm_run_stop(int runid)
{
return killrunner(runid, SIGSTOP, as_stopped);
}
+/*
+ * Continue (aka resume) the runner of 'runid'
+ *
+ * Returns 0 in case of success or -1 in case of error
+ */
int afm_run_continue(int runid)
{
return killrunner(runid, SIGCONT, as_running);
}
-static json_object *mkstate(struct apprun *runner)
-{
- const char *state;
- struct json_object *result, *obj;
- int rc;
-
- /* the structure */
- result = json_object_new_object();
- if (result == NULL)
- goto error;
-
- /* the runid */
- if (!j_add_integer(result, "runid", runner->runid))
- goto error2;
-
- /* the state */
- switch(runner->state) {
- case as_starting:
- case as_running:
- state = "running";
- break;
- case as_stopped:
- state = "stopped";
- break;
- default:
- state = "terminated";
- break;
- }
- if (!j_add_string(result, "state", state))
- goto error2;
-
- /* the application id */
- rc = json_object_object_get_ex(runner->appli, "public", &obj);
- assert(rc);
- rc = json_object_object_get_ex(obj, "id", &obj);
- assert(rc);
- if (!j_add(result, "id", obj))
- goto error2;
- json_object_get(obj);
-
- /* done */
- return result;
-
-error2:
- json_object_put(result);
-error:
- errno = ENOMEM;
- return NULL;
-}
-
+/*
+ * Get the list of the runners.
+ *
+ * Returns the list or NULL in case of error.
+ */
struct json_object *afm_run_list()
{
struct json_object *result, *obj;
@@ -400,9 +562,13 @@ struct json_object *afm_run_list()
if (result == NULL)
goto error;
+ /* iterate over runners */
for (i = 0 ; i < ROOT_RUNNERS_COUNT ; i++) {
- for (runner = runners_by_runid[i] ; runner ; runner = runner->next_by_runid) {
- if (runner->state != as_terminating && runner->state != as_terminated) {
+ runner = runners_by_runid[i];
+ while (runner) {
+ if (runner->state != as_terminating
+ && runner->state != as_terminated) {
+ /* adds the living runner */
obj = mkstate(runner);
if (obj == NULL)
goto error2;
@@ -411,6 +577,7 @@ struct json_object *afm_run_list()
goto error2;
}
}
+ runner = runner->next_by_runid;
}
}
return result;
@@ -422,10 +589,16 @@ error:
return NULL;
}
+/*
+ * Get the state of the runner of 'runid'.
+ *
+ * Returns the state or NULL in case of success
+ */
struct json_object *afm_run_state(int runid)
{
struct apprun *runner = getrunner(runid);
- if (runner == NULL || runner->state == as_terminating || runner->state == as_terminated) {
+ if (runner == NULL || runner->state == as_terminating
+ || runner->state == as_terminated) {
errno = ENOENT;
return NULL;
}
@@ -434,6 +607,9 @@ struct json_object *afm_run_state(int runid)
/**************** INITIALISATION **********************/
+/*
+ * Initialize the module
+ */
int afm_run_init()
{
char buf[2048];
@@ -456,14 +632,16 @@ int afm_run_init()
ERROR("getpwuid_r failed for uid=%d: %m",(int)me);
return -1;
}
- rc = snprintf(dir, sizeof dir, "%s/%s", passwd.pw_dir, fwk_user_app_dir);
+ rc = snprintf(dir, sizeof dir, "%s/%s", passwd.pw_dir,
+ fwk_user_app_dir);
if (rc >= sizeof dir) {
ERROR("buffer overflow in user_app_dir for uid=%d",(int)me);
return -1;
}
rc = create_directory(dir, 0755, 1);
if (rc && errno != EEXIST) {
- ERROR("creation of directory %s failed in user_app_dir: %m", dir);
+ ERROR("creation of directory %s failed in user_app_dir: %m",
+ dir);
return -1;
}
homeappdir = strdup(dir);