From 0beff6e84858ffc4468276865d3709d7ee0b1852 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Jos=C3=A9=20Bollo?= Date: Tue, 15 Mar 2016 11:14:21 +0100 Subject: [PATCH] afm-user-daemon: comments MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Change-Id: I464404029c3ef4a1572a48d67d370aec529e8b3b Signed-off-by: José Bollo --- src/afm-user-daemon.c | 265 ++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 192 insertions(+), 73 deletions(-) diff --git a/src/afm-user-daemon.c b/src/afm-user-daemon.c index 04f5fea..2615cf5 100644 --- a/src/afm-user-daemon.c +++ b/src/afm-user-daemon.c @@ -32,25 +32,30 @@ #include "afm-launch-mode.h" #include "afm-run.h" +/* + * name of the application + */ static const char appname[] = "afm-user-daemon"; -static void usage() -{ - printf( - "usage: %s [-q] [-v] [-m mode] [-r rootdir]... [-a appdir]...\n" - "\n" - " -a appdir adds an application directory\n" - " -r rootdir adds a root directory of applications\n" - " -m mode set default launch mode (local or remote)\n" - " -d run as a daemon\n" - " -q quiet\n" - " -v verbose\n" - "\n", - appname - ); -} +/* + * string for printing usage + */ +static const char usagestr[] = + "usage: %s [-q] [-v] [-m mode] [-r rootdir]... [-a appdir]...\n" + "\n" + " -a appdir adds an application directory\n" + " -r rootdir adds a root directory of applications\n" + " -m mode set default launch mode (local or remote)\n" + " -d run as a daemon\n" + " -q quiet\n" + " -v verbose\n" + "\n"; -static struct option options[] = { +/* + * Option definition for getopt_long + */ +static const char options_s[] = "hdqvr:a:m:"; +static struct option options_l[] = { { "root", required_argument, NULL, 'r' }, { "application", required_argument, NULL, 'a' }, { "mode", required_argument, NULL, 'm' }, @@ -61,26 +66,60 @@ static struct option options[] = { { NULL, 0, NULL, 0 } }; +/* + * Connections to D-Bus + * This is an array for using the function + * jbus_read_write_dispatch_multiple + * directly without transformations. + */ static struct jbus *jbuses[2]; +#define system_bus jbuses[0] +#define user_bus jbuses[1] + +/* + * Handle to the database of applications + */ static struct afm_db *afdb; +/* + * Returned error strings + */ const char error_nothing[] = "[]"; const char error_bad_request[] = "\"bad request\""; const char error_not_found[] = "\"not found\""; const char error_cant_start[] = "\"can't start\""; const char error_system[] = "\"system error\""; -static const char *getappid(struct json_object *obj) -{ - return json_type_string == json_object_get_type(obj) ? json_object_get_string(obj) : NULL; -} -static int getrunid(struct json_object *obj) +/* + * retrieves the 'runid' in 'obj' parameters received with the + * request 'jreq' for the 'method'. + * + * Returns 1 in case of success. + * Otherwise, if the 'runid' can't be retrived, an error stating + * the bad request is replied for 'jreq' and 0 is returned. + */ +static int onrunid(struct jreq *jreq, struct json_object *obj, + const char *method, int *runid) { - return json_type_int == json_object_get_type(obj) ? json_object_get_int(obj) : 0; + if (!j_read_integer(obj, runid) + && !j_read_integer_at(obj, "runid", runid)) { + INFO("bad request method %s: %s", method, + json_object_to_json_string(obj)); + jbus_reply_error_s(jreq, error_bad_request); + return 0; + } + + INFO("method %s called for %d", method, *runid); + return 1; } -static void reply(struct jreq *jreq, struct json_object *resp, const char *errstr) +/* + * Sends the reply 'resp' to the request 'jreq' if 'resp' is not NULL. + * Otherwise, when 'resp' is NULL replies the error string 'errstr'. + */ +static void reply(struct jreq *jreq, struct json_object *resp, + const char *errstr) { if (resp) jbus_reply_j(jreq, resp); @@ -88,14 +127,23 @@ static void reply(struct jreq *jreq, struct json_object *resp, const char *errst jbus_reply_error_s(jreq, errstr); } -static void reply_status(struct jreq *jreq, int status) +/* + * Sends the reply "true" to the request 'jreq' if 'status' is zero. + * Otherwise, when 'status' is not zero replies the error string 'errstr'. + */ +static void reply_status(struct jreq *jreq, int status, const char *errstr) { if (status) - jbus_reply_error_s(jreq, error_not_found); + jbus_reply_error_s(jreq, errstr); else jbus_reply_s(jreq, "true"); } +/* + * On query "runnables" from 'jreq' with parameters of 'obj'. + * + * Nothing is expected in 'obj' that can be anything. + */ static void on_runnables(struct jreq *jreq, struct json_object *obj) { struct json_object *resp; @@ -105,17 +153,36 @@ static void on_runnables(struct jreq *jreq, struct json_object *obj) json_object_put(resp); } +/* + * On query "detail" from 'jreq' with parameters of 'obj'. + */ static void on_detail(struct jreq *jreq, struct json_object *obj) { const char *appid; struct json_object *resp; - appid = getappid(obj); + + /* get the parameters */ + if (j_read_string(obj, &appid)) + ; /* appid as a string */ + else if (j_read_string_at(obj, "id", &appid)) + ; /* appid as obj.id string */ + else { + INFO("method detail called but bad request!"); + jbus_reply_error_s(jreq, error_bad_request); + return; + } + + /* wants details for appid */ INFO("method detail called for %s", appid); resp = afm_db_get_application_public(afdb, appid); reply(jreq, resp, error_not_found); json_object_put(resp); } + +/* + * On query "start" from 'jreq' with parameters of 'obj'. + */ static void on_start(struct jreq *jreq, struct json_object *obj) { const char *appid, *modestr; @@ -142,7 +209,8 @@ static void on_start(struct jreq *jreq, struct json_object *obj) } /* get the application */ - INFO("method start called for %s mode=%s", appid, name_of_launch_mode(mode)); + INFO("method start called for %s mode=%s", appid, + name_of_launch_mode(mode)); appli = afm_db_get_application(afdb, appid); if (appli == NULL) { jbus_reply_error_s(jreq, error_not_found); @@ -168,43 +236,56 @@ static void on_start(struct jreq *jreq, struct json_object *obj) /* returns the runid and its uri */ resp = json_object_new_object(); - if (resp != NULL && j_add_integer(resp, "runid", runid) && j_add_string(resp, "uri", uri)) + if (resp != NULL && j_add_integer(resp, "runid", runid) + && j_add_string(resp, "uri", uri)) jbus_reply_j(jreq, resp); else { afm_run_stop(runid); - jbus_reply_error_s(jreq, error_cant_start); + jbus_reply_error_s(jreq, error_system); } json_object_put(resp); free(uri); } +/* + * On query "stop" from 'jreq' with parameters of 'obj'. + */ static void on_stop(struct jreq *jreq, struct json_object *obj) { int runid, status; - runid = getrunid(obj); - INFO("method stop called for %d", runid); - status = afm_run_stop(runid); - reply_status(jreq, status); + if (onrunid(jreq, obj, "stop", &runid)) { + status = afm_run_stop(runid); + reply_status(jreq, status, error_not_found); + } } +/* + * On query "continue" from 'jreq' with parameters of 'obj'. + */ static void on_continue(struct jreq *jreq, struct json_object *obj) { int runid, status; - runid = getrunid(obj); - INFO("method continue called for %d", runid); - status = afm_run_continue(runid); - reply_status(jreq, status); + if (onrunid(jreq, obj, "continue", &runid)) { + status = afm_run_continue(runid); + reply_status(jreq, status, error_not_found); + } } +/* + * On query "terminate" from 'jreq' with parameters of 'obj'. + */ static void on_terminate(struct jreq *jreq, struct json_object *obj) { int runid, status; - runid = getrunid(obj); - INFO("method terminate called for %d", runid); - status = afm_run_terminate(runid); - reply_status(jreq, status); + if (onrunid(jreq, obj, "terminate", &runid)) { + status = afm_run_terminate(runid); + reply_status(jreq, status, error_not_found); + } } +/* + * On query "runners" from 'jreq' with parameters of 'obj'. + */ static void on_runners(struct jreq *jreq, struct json_object *obj) { struct json_object *resp; @@ -214,22 +295,37 @@ static void on_runners(struct jreq *jreq, struct json_object *obj) json_object_put(resp); } +/* + * On query "state" from 'jreq' with parameters of 'obj'. + */ static void on_state(struct jreq *jreq, struct json_object *obj) { int runid; struct json_object *resp; - runid = getrunid(obj); - INFO("method state called for %d", runid); - resp = afm_run_state(runid); - reply(jreq, resp, error_not_found); - json_object_put(resp); + if (onrunid(jreq, obj, "state", &runid)) { + resp = afm_run_state(runid); + reply(jreq, resp, error_not_found); + json_object_put(resp); + } } +/* + * Calls the system daemon to achieve application management of + * the 'method' gotten from 'jreq' with the parameter's string 'msg'. + * + * The principle is very simple: call the corresponding system method + * and reply its response to the caller. + * + * The request and reply is synchronous and is blocking. + * It is possible to implment it in an asynchrounous way but it + * would brake the common behaviour. It would be a call like + * jbus_call_ss(system_bus, method, msg, callback, jreq) + */ static void propagate(struct jreq *jreq, const char *msg, const char *method) { char *reply; INFO("method %s propagated with %s", method, msg); - reply = jbus_call_ss_sync(jbuses[0], method, msg); + reply = jbus_call_ss_sync(system_bus, method, msg); if (reply) { jbus_reply_s(jreq, reply); free(reply); @@ -238,24 +334,37 @@ static void propagate(struct jreq *jreq, const char *msg, const char *method) jbus_reply_error_s(jreq, error_system); } +/* + * On query "install" from 'jreq' with parameters of 'msg'. + */ static void on_install(struct jreq *jreq, const char *msg) { return propagate(jreq, msg, "install"); } +/* + * On query "uninstall" from 'jreq' with parameters of 'msg'. + */ static void on_uninstall(struct jreq *jreq, const char *msg) { return propagate(jreq, msg, "uninstall"); } +/* + * On system signaling that applications list changed + */ static void on_signal_changed(struct json_object *obj) { /* update the database */ afm_db_update_applications(afdb); /* re-propagate now */ - jbus_send_signal_j(jbuses[1], "changed", obj); + jbus_send_signal_j(user_bus, "changed", obj); } +/* + * Tiny routine to daemonize the program + * Return 0 on success or -1 on failure. + */ static int daemonize() { int rc = fork(); @@ -266,6 +375,9 @@ static int daemonize() return 0; } +/* + * ENTRY POINT OF AFM-USER-DAEMON + */ int main(int ac, char **av) { int i, daemon = 0; @@ -274,10 +386,10 @@ int main(int ac, char **av) LOGAUTH(appname); /* first interpretation of arguments */ - while ((i = getopt_long(ac, av, "hdqvr:a:m:", options, NULL)) >= 0) { + while ((i = getopt_long(ac, av, options_s, options_l, NULL)) >= 0) { switch (i) { case 'h': - usage(); + printf(usagestr, appname); return 0; case 'q': if (verbosity) @@ -332,7 +444,7 @@ int main(int ac, char **av) /* second interpretation of arguments */ optind = 1; - while ((i = getopt_long(ac, av, "hdqvr:a:m:", options, NULL)) >= 0) { + while ((i = getopt_long(ac, av, options_s, options_l, NULL)) >= 0) { switch (i) { case 'r': if (afm_db_add_root(afdb, optarg)) { @@ -342,9 +454,9 @@ int main(int ac, char **av) break; case 'a': if (afm_db_add_application(afdb, optarg)) { - ERROR("can't add application %s", optarg); - return 1; - } + ERROR("can't add application %s", optarg); + return 1; + } break; } } @@ -355,47 +467,54 @@ int main(int ac, char **av) return 1; } + /* daemonize if requested */ if (daemon && daemonize()) { ERROR("daemonization failed"); return 1; } - /* init observers */ - jbuses[0] = create_jbus_system(AFM_SYSTEM_DBUS_PATH); - if (!jbuses[0]) { + /* connects to the system bus */ + system_bus = create_jbus_system(AFM_SYSTEM_DBUS_PATH); + if (!system_bus) { ERROR("create_jbus failed for system"); return 1; } - if(jbus_on_signal_j(jbuses[0], "changed", on_signal_changed)) { + + /* observe signals of system */ + if(jbus_on_signal_j(system_bus, "changed", on_signal_changed)) { ERROR("adding signal observer failed"); return 1; } - /* init service */ - jbuses[1] = create_jbus_session(AFM_USER_DBUS_PATH); - if (!jbuses[1]) { + /* connect to the session bus */ + user_bus = create_jbus_session(AFM_USER_DBUS_PATH); + if (!user_bus) { ERROR("create_jbus failed"); return 1; } - if(jbus_add_service_j(jbuses[1], "runnables", on_runnables) - || jbus_add_service_j(jbuses[1], "detail", on_detail) - || jbus_add_service_j(jbuses[1], "start", on_start) - || jbus_add_service_j(jbuses[1], "terminate", on_terminate) - || jbus_add_service_j(jbuses[1], "stop", on_stop) - || jbus_add_service_j(jbuses[1], "continue", on_continue) - || jbus_add_service_j(jbuses[1], "runners", on_runners) - || jbus_add_service_j(jbuses[1], "state", on_state) - || jbus_add_service_s(jbuses[1], "install", on_install) - || jbus_add_service_s(jbuses[1], "uninstall", on_uninstall)) { + + /* init services */ + if (jbus_add_service_j(user_bus, "runnables", on_runnables) + || jbus_add_service_j(user_bus, "detail", on_detail) + || jbus_add_service_j(user_bus, "start", on_start) + || jbus_add_service_j(user_bus, "terminate", on_terminate) + || jbus_add_service_j(user_bus, "stop", on_stop) + || jbus_add_service_j(user_bus, "continue", on_continue) + || jbus_add_service_j(user_bus, "runners", on_runners) + || jbus_add_service_j(user_bus, "state", on_state) + || jbus_add_service_s(user_bus, "install", on_install) + || jbus_add_service_s(user_bus, "uninstall", on_uninstall)) { ERROR("adding services failed"); return 1; } - /* start and run */ - if (jbus_start_serving(jbuses[1])) { + /* start servicing */ + if (jbus_start_serving(user_bus)) { ERROR("can't start server"); return 1; } + + /* run until error */ while (jbus_read_write_dispatch_multiple(jbuses, 2, -1, 20) >= 0); return 0; } -- 2.16.6