Hi, I want to write an application which repeats the following procedure for several (100+) bluetooth (low energy) devices: 1. connect 2. read register values 3. disconnect Therefore I modified the source code from /attrib/interactive.c. For testing purposes I am only looping over one device. See attached source code. The code works fine. It connects, reads the values and disconnects. However, after 1020 repetitions, the following error occurs: (process:10205): GLib-WARNING **: poll(2) failed due to: Invalid argument. I think the problem has to do with some sockets / file descriptors not being closed properly. Can someone help me to get this fixed? Thank you Markus
/* * * BlueZ - Bluetooth protocol stack for Linux * * Copyright (C) 2011 Nokia Corporation * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include <string.h> #include <stdlib.h> #include <stdarg.h> #include <errno.h> #include <stdio.h> #include <unistd.h> #include <signal.h> #include <sys/signalfd.h> #include <glib.h> #include <readline/readline.h> #include <readline/history.h> #include "lib/uuid.h" #include <btio/btio.h> #include "att.h" #include "gattrib.h" #include "gatt.h" #include "gatttool.h" #include "client/display.h" static GIOChannel *iochannel = NULL; static GAttrib *attrib = NULL; static GMainLoop *event_loop; static GString *prompt; static char *opt_src = NULL; static char *opt_dst = NULL; static char *opt_dst_type = NULL; static char *opt_sec_level = NULL; static int opt_psm = 0; static int opt_mtu = 0; static int start; static int end; static gboolean requested_read; static gboolean done_read; static void cmd_help(int argcp, char **argvp); static enum state { STATE_DISCONNECTED, STATE_CONNECTING, STATE_CONNECTED } conn_state; static int loop_counter; #define error(fmt, arg...) \ rl_printf(COLOR_RED "Error: " COLOR_OFF fmt, ## arg) #define failed(fmt, arg...) \ rl_printf(COLOR_RED "Command Failed: " COLOR_OFF fmt, ## arg) static char *get_prompt(void) { if (conn_state == STATE_CONNECTED) g_string_assign(prompt, COLOR_BLUE); else g_string_assign(prompt, ""); if (opt_dst) g_string_append_printf(prompt, "[%17s]", opt_dst); else g_string_append_printf(prompt, "[%17s]", ""); if (conn_state == STATE_CONNECTED) g_string_append(prompt, COLOR_OFF); if (opt_psm) g_string_append(prompt, "[BR]"); else g_string_append(prompt, "[LE]"); g_string_append(prompt, "> "); return prompt->str; } static void set_state(enum state st) { conn_state = st; rl_set_prompt(get_prompt()); } static void events_handler(const uint8_t *pdu, uint16_t len, gpointer user_data) { uint8_t *opdu; uint16_t handle, i, olen; size_t plen; GString *s; handle = att_get_u16(&pdu[1]); switch (pdu[0]) { case ATT_OP_HANDLE_NOTIFY: s = g_string_new(NULL); g_string_printf(s, "Notification handle = 0x%04x value: ", handle); break; case ATT_OP_HANDLE_IND: s = g_string_new(NULL); g_string_printf(s, "Indication handle = 0x%04x value: ", handle); break; default: error("Invalid opcode\n"); return; } for (i = 3; i < len; i++) g_string_append_printf(s, "%02x ", pdu[i]); rl_printf("%s\n", s->str); g_string_free(s, TRUE); if (pdu[0] == ATT_OP_HANDLE_NOTIFY) return; opdu = g_attrib_get_buffer(attrib, &plen); olen = enc_confirmation(opdu, plen); if (olen > 0) g_attrib_send(attrib, 0, opdu, olen, NULL, NULL, NULL); } static void connect_cb(GIOChannel *io, GError *err, gpointer user_data) { if (err) { set_state(STATE_DISCONNECTED); error("%s\n", err->message); return; } attrib = g_attrib_new(iochannel); g_attrib_register(attrib, ATT_OP_HANDLE_NOTIFY, GATTRIB_ALL_HANDLES, events_handler, attrib, NULL); g_attrib_register(attrib, ATT_OP_HANDLE_IND, GATTRIB_ALL_HANDLES, events_handler, attrib, NULL); set_state(STATE_CONNECTED); rl_printf("Connection successful\n"); } static void disconnect_io() { if (conn_state == STATE_DISCONNECTED) return; g_attrib_unref(attrib); attrib = NULL; opt_mtu = 0; g_io_channel_shutdown(iochannel, FALSE, NULL); g_io_channel_unref(iochannel); iochannel = NULL; set_state(STATE_DISCONNECTED); } static void primary_all_cb(GSList *services, guint8 status, gpointer user_data) { GSList *l; if (status) { error("Discover all primary services failed: %s\n", att_ecode2str(status)); return; } if (services == NULL) { error("No primary service found\n"); return; } for (l = services; l; l = l->next) { struct gatt_primary *prim = l->data; rl_printf("attr handle: 0x%04x, end grp handle: 0x%04x uuid: %s\n", prim->range.start, prim->range.end, prim->uuid); } } static void primary_by_uuid_cb(GSList *ranges, guint8 status, gpointer user_data) { GSList *l; if (status) { error("Discover primary services by UUID failed: %s\n", att_ecode2str(status)); return; } if (ranges == NULL) { error("No service UUID found\n"); return; } for (l = ranges; l; l = l->next) { struct att_range *range = l->data; rl_printf("Starting handle: 0x%04x Ending handle: 0x%04x\n", range->start, range->end); } } static void included_cb(GSList *includes, guint8 status, gpointer user_data) { GSList *l; if (status) { error("Find included services failed: %s\n", att_ecode2str(status)); return; } if (includes == NULL) { rl_printf("No included services found for this range\n"); return; } for (l = includes; l; l = l->next) { struct gatt_included *incl = l->data; rl_printf("handle: 0x%04x, start handle: 0x%04x, " "end handle: 0x%04x uuid: %s\n", incl->handle, incl->range.start, incl->range.end, incl->uuid); } } static void char_cb(GSList *characteristics, guint8 status, gpointer user_data) { GSList *l; if (status) { error("Discover all characteristics failed: %s\n", att_ecode2str(status)); return; } for (l = characteristics; l; l = l->next) { struct gatt_char *chars = l->data; rl_printf("handle: 0x%04x, char properties: 0x%02x, char value " "handle: 0x%04x, uuid: %s\n", chars->handle, chars->properties, chars->value_handle, chars->uuid); } } static void char_desc_cb(guint8 status, const guint8 *pdu, guint16 plen, gpointer user_data) { struct att_data_list *list; guint8 format; uint16_t handle = 0xffff; int i; if (status != 0) { rl_printf("Discover descriptors finished: %s\n", att_ecode2str(status)); return; } list = dec_find_info_resp(pdu, plen, &format); if (list == NULL) return; for (i = 0; i < list->num; i++) { char uuidstr[MAX_LEN_UUID_STR]; uint8_t *value; bt_uuid_t uuid; value = list->data[i]; handle = att_get_u16(value); if (format == 0x01) uuid = att_get_uuid16(&value[2]); else uuid = att_get_uuid128(&value[2]); bt_uuid_to_string(&uuid, uuidstr, MAX_LEN_UUID_STR); rl_printf("handle: 0x%04x, uuid: %s\n", handle, uuidstr); } att_data_list_free(list); if (handle != 0xffff && handle < end) gatt_discover_char_desc(attrib, handle + 1, end, char_desc_cb, NULL); } static void char_read_cb(guint8 status, const guint8 *pdu, guint16 plen, gpointer user_data) { uint8_t value[plen]; ssize_t vlen; int i; GString *s; if (status != 0) { error("Characteristic value/descriptor read failed: %s\n", att_ecode2str(status)); return; } vlen = dec_read_resp(pdu, plen, value, sizeof(value)); if (vlen < 0) { error("Protocol error\n"); return; } s = g_string_new("Characteristic value/descriptor: "); for (i = 0; i < vlen; i++) g_string_append_printf(s, "%02x ", value[i]); rl_printf("%s\n", s->str); g_string_free(s, TRUE); } static void char_read_by_uuid_cb(guint8 status, const guint8 *pdu, guint16 plen, gpointer user_data) { struct att_data_list *list; int i; GString *s; if (status != 0) { error("Read characteristics by UUID failed: %s\n", att_ecode2str(status)); return; } list = dec_read_by_type_resp(pdu, plen); if (list == NULL) return; s = g_string_new(NULL); for (i = 0; i < list->num; i++) { uint8_t *value = list->data[i]; int j; g_string_printf(s, "handle: 0x%04x \t value: ", att_get_u16(value)); value += 2; for (j = 0; j < list->len - 2; j++, value++) g_string_append_printf(s, "%02x ", *value); rl_printf("%s\n", s->str); } att_data_list_free(list); g_string_free(s, TRUE); done_read = 1; } static void cmd_exit(int argcp, char **argvp) { rl_callback_handler_remove(); g_main_loop_quit(event_loop); } static gboolean channel_watcher(GIOChannel *chan, GIOCondition cond, gpointer user_data) { disconnect_io(); return FALSE; } static void cmd_connect(int argcp, char **argvp) { GError *gerr = NULL; if (conn_state != STATE_DISCONNECTED) return; if (argcp > 1) { g_free(opt_dst); opt_dst = g_strdup(argvp[1]); g_free(opt_dst_type); if (argcp > 2) opt_dst_type = g_strdup(argvp[2]); else opt_dst_type = g_strdup("public"); } if (opt_dst == NULL) { error("Remote Bluetooth address required\n"); return; } rl_printf("Attempting to connect to %s\n", opt_dst); set_state(STATE_CONNECTING); iochannel = gatt_connect(opt_src, opt_dst, opt_dst_type, opt_sec_level, opt_psm, opt_mtu, connect_cb, &gerr); if (iochannel == NULL) { set_state(STATE_DISCONNECTED); error("%s\n", gerr->message); g_error_free(gerr); } else g_io_add_watch(iochannel, G_IO_HUP, channel_watcher, NULL); } static void cmd_disconnect(int argcp, char **argvp) { disconnect_io(); } static void cmd_primary(int argcp, char **argvp) { bt_uuid_t uuid; if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp == 1) { gatt_discover_primary(attrib, NULL, primary_all_cb, NULL); return; } if (bt_string_to_uuid(&uuid, argvp[1]) < 0) { error("Invalid UUID\n"); return; } gatt_discover_primary(attrib, &uuid, primary_by_uuid_cb, NULL); } static int strtohandle(const char *src) { char *e; int dst; errno = 0; dst = strtoll(src, &e, 16); if (errno != 0 || *e != '\0') return -EINVAL; return dst; } static void cmd_included(int argcp, char **argvp) { int start = 0x0001; int end = 0xffff; if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp > 1) { start = strtohandle(argvp[1]); if (start < 0) { error("Invalid start handle: %s\n", argvp[1]); return; } end = start; } if (argcp > 2) { end = strtohandle(argvp[2]); if (end < 0) { error("Invalid end handle: %s\n", argvp[2]); return; } } gatt_find_included(attrib, start, end, included_cb, NULL); } static void cmd_char(int argcp, char **argvp) { int start = 0x0001; int end = 0xffff; if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp > 1) { start = strtohandle(argvp[1]); if (start < 0) { error("Invalid start handle: %s\n", argvp[1]); return; } } if (argcp > 2) { end = strtohandle(argvp[2]); if (end < 0) { error("Invalid end handle: %s\n", argvp[2]); return; } } if (argcp > 3) { bt_uuid_t uuid; if (bt_string_to_uuid(&uuid, argvp[3]) < 0) { error("Invalid UUID\n"); return; } gatt_discover_char(attrib, start, end, &uuid, char_cb, NULL); return; } gatt_discover_char(attrib, start, end, NULL, char_cb, NULL); } static void cmd_char_desc(int argcp, char **argvp) { if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp > 1) { start = strtohandle(argvp[1]); if (start < 0) { error("Invalid start handle: %s\n", argvp[1]); return; } } else start = 0x0001; if (argcp > 2) { end = strtohandle(argvp[2]); if (end < 0) { error("Invalid end handle: %s\n", argvp[2]); return; } } else end = 0xffff; gatt_discover_char_desc(attrib, start, end, char_desc_cb, NULL); } static void cmd_read_hnd(int argcp, char **argvp) { int handle; if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp < 2) { error("Missing argument: handle\n"); return; } handle = strtohandle(argvp[1]); if (handle < 0) { error("Invalid handle: %s\n", argvp[1]); return; } gatt_read_char(attrib, handle, char_read_cb, attrib); } static void cmd_read_uuid(int argcp, char **argvp) { int start = 0x0001; int end = 0xffff; bt_uuid_t uuid; if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp < 2) { error("Missing argument: UUID\n"); return; } if (bt_string_to_uuid(&uuid, argvp[1]) < 0) { error("Invalid UUID\n"); return; } if (argcp > 2) { start = strtohandle(argvp[2]); if (start < 0) { error("Invalid start handle: %s\n", argvp[1]); return; } } if (argcp > 3) { end = strtohandle(argvp[3]); if (end < 0) { error("Invalid end handle: %s\n", argvp[2]); return; } } gatt_read_char_by_uuid(attrib, start, end, &uuid, char_read_by_uuid_cb, NULL); requested_read = 1; } static void char_write_req_cb(guint8 status, const guint8 *pdu, guint16 plen, gpointer user_data) { if (status != 0) { error("Characteristic Write Request failed: " "%s\n", att_ecode2str(status)); return; } if (!dec_write_resp(pdu, plen) && !dec_exec_write_resp(pdu, plen)) { error("Protocol error\n"); return; } rl_printf("Characteristic value was written successfully\n"); } static void cmd_char_write(int argcp, char **argvp) { uint8_t *value; size_t plen; int handle; if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (argcp < 3) { rl_printf("Usage: %s <handle> <new value>\n", argvp[0]); return; } handle = strtohandle(argvp[1]); if (handle <= 0) { error("A valid handle is required\n"); return; } plen = gatt_attr_data_from_string(argvp[2], &value); if (plen == 0) { error("Invalid value\n"); return; } if (g_strcmp0("char-write-req", argvp[0]) == 0) gatt_write_char(attrib, handle, value, plen, char_write_req_cb, NULL); else gatt_write_cmd(attrib, handle, value, plen, NULL, NULL); g_free(value); } static void cmd_sec_level(int argcp, char **argvp) { GError *gerr = NULL; BtIOSecLevel sec_level; if (argcp < 2) { rl_printf("sec-level: %s\n", opt_sec_level); return; } if (strcasecmp(argvp[1], "medium") == 0) sec_level = BT_IO_SEC_MEDIUM; else if (strcasecmp(argvp[1], "high") == 0) sec_level = BT_IO_SEC_HIGH; else if (strcasecmp(argvp[1], "low") == 0) sec_level = BT_IO_SEC_LOW; else { rl_printf("Allowed values: low | medium | high\n"); return; } g_free(opt_sec_level); opt_sec_level = g_strdup(argvp[1]); if (conn_state != STATE_CONNECTED) return; if (opt_psm) { rl_printf("Change will take effect on reconnection\n"); return; } bt_io_set(iochannel, &gerr, BT_IO_OPT_SEC_LEVEL, sec_level, BT_IO_OPT_INVALID); if (gerr) { error("%s\n", gerr->message); g_error_free(gerr); } } static void exchange_mtu_cb(guint8 status, const guint8 *pdu, guint16 plen, gpointer user_data) { uint16_t mtu; if (status != 0) { error("Exchange MTU Request failed: %s\n", att_ecode2str(status)); return; } if (!dec_mtu_resp(pdu, plen, &mtu)) { error("Protocol error\n"); return; } mtu = MIN(mtu, opt_mtu); /* Set new value for MTU in client */ if (g_attrib_set_mtu(attrib, mtu)) rl_printf("MTU was exchanged successfully: %d\n", mtu); else error("Error exchanging MTU\n"); } static void cmd_mtu(int argcp, char **argvp) { if (conn_state != STATE_CONNECTED) { failed("Disconnected\n"); return; } if (opt_psm) { failed("Operation is only available for LE transport.\n"); return; } if (argcp < 2) { rl_printf("Usage: mtu <value>\n"); return; } if (opt_mtu) { failed("MTU exchange can only occur once per connection.\n"); return; } errno = 0; opt_mtu = strtoll(argvp[1], NULL, 0); if (errno != 0 || opt_mtu < ATT_DEFAULT_LE_MTU) { error("Invalid value. Minimum MTU size is %d\n", ATT_DEFAULT_LE_MTU); return; } gatt_exchange_mtu(attrib, opt_mtu, exchange_mtu_cb, NULL); } static struct { const char *cmd; void (*func)(int argcp, char **argvp); const char *params; const char *desc; } commands[] = { { "help", cmd_help, "", "Show this help"}, { "exit", cmd_exit, "", "Exit interactive mode" }, { "quit", cmd_exit, "", "Exit interactive mode" }, { "connect", cmd_connect, "[address [address type]]", "Connect to a remote device" }, { "disconnect", cmd_disconnect, "", "Disconnect from a remote device" }, { "primary", cmd_primary, "[UUID]", "Primary Service Discovery" }, { "included", cmd_included, "[start hnd [end hnd]]", "Find Included Services" }, { "characteristics", cmd_char, "[start hnd [end hnd [UUID]]]", "Characteristics Discovery" }, { "char-desc", cmd_char_desc, "[start hnd] [end hnd]", "Characteristics Descriptor Discovery" }, { "char-read-hnd", cmd_read_hnd, "<handle>", "Characteristics Value/Descriptor Read by handle" }, { "char-read-uuid", cmd_read_uuid, "<UUID> [start hnd] [end hnd]", "Characteristics Value/Descriptor Read by UUID" }, { "char-write-req", cmd_char_write, "<handle> <new value>", "Characteristic Value Write (Write Request)" }, { "char-write-cmd", cmd_char_write, "<handle> <new value>", "Characteristic Value Write (No response)" }, { "sec-level", cmd_sec_level, "[low | medium | high]", "Set security level. Default: low" }, { "mtu", cmd_mtu, "<value>", "Exchange MTU for GATT/ATT" }, { NULL, NULL, NULL} }; static void cmd_help(int argcp, char **argvp) { int i; for (i = 0; commands[i].cmd; i++) rl_printf("%-15s %-30s %s\n", commands[i].cmd, commands[i].params, commands[i].desc); } static void parse_line(char *line_read) { char **argvp; int argcp; int i; if (line_read == NULL) { rl_printf("\n"); //cmd_exit(0, NULL); return; } line_read = g_strstrip(line_read); if (*line_read == '\0') goto done; add_history(line_read); if (g_shell_parse_argv(line_read, &argcp, &argvp, NULL) == FALSE) goto done; for (i = 0; commands[i].cmd; i++) if (strcasecmp(commands[i].cmd, argvp[0]) == 0) break; if (commands[i].cmd) commands[i].func(argcp, argvp); else error("%s: command not found\n", argvp[0]); g_strfreev(argvp); done: ; //free(line_read); } static gboolean prompt_read(GIOChannel *chan, GIOCondition cond, gpointer user_data) { if (cond & (G_IO_HUP | G_IO_ERR | G_IO_NVAL)) { g_io_channel_unref(chan); return FALSE; } rl_callback_read_char(); return TRUE; } static char *completion_generator(const char *text, int state) { static int index = 0, len = 0; const char *cmd = NULL; if (state == 0) { index = 0; len = strlen(text); } while ((cmd = commands[index].cmd) != NULL) { index++; if (strncmp(cmd, text, len) == 0) return strdup(cmd); } return NULL; } static char **commands_completion(const char *text, int start, int end) { if (start == 0) return rl_completion_matches(text, &completion_generator); else return NULL; } static guint setup_standard_input(void) { GIOChannel *channel; guint source; channel = g_io_channel_unix_new(fileno(stdin)); source = g_io_add_watch(channel, G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_NVAL, prompt_read, NULL); g_io_channel_unref(channel); return source; } static gboolean signal_handler(GIOChannel *channel, GIOCondition condition, gpointer user_data) { static unsigned int __terminated = 0; struct signalfd_siginfo si; ssize_t result; int fd; if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) { g_main_loop_quit(event_loop); return FALSE; } fd = g_io_channel_unix_get_fd(channel); result = read(fd, &si, sizeof(si)); if (result != sizeof(si)) return FALSE; switch (si.ssi_signo) { case SIGINT: rl_replace_line("", 0); rl_crlf(); rl_on_new_line(); rl_redisplay(); break; case SIGTERM: if (__terminated == 0) { rl_replace_line("", 0); rl_crlf(); g_main_loop_quit(event_loop); } __terminated = 1; break; } return TRUE; } static guint setup_signalfd(void) { GIOChannel *channel; guint source; sigset_t mask; int fd; sigemptyset(&mask); sigaddset(&mask, SIGINT); sigaddset(&mask, SIGTERM); if (sigprocmask(SIG_BLOCK, &mask, NULL) < 0) { perror("Failed to set signal mask"); return 0; } fd = signalfd(-1, &mask, 0); if (fd < 0) { perror("Failed to create signal descriptor"); return 0; } channel = g_io_channel_unix_new(fd); g_io_channel_set_close_on_unref(channel, TRUE); g_io_channel_set_encoding(channel, NULL, NULL); g_io_channel_set_buffered(channel, FALSE); source = g_io_add_watch(channel, G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_NVAL, signal_handler, NULL); g_io_channel_unref(channel); return source; } gboolean callback_fastloop(GIOChannel *source, GIOCondition condition,gpointer data) { if (conn_state == STATE_DISCONNECTED) { if (conn_state != STATE_CONNECTING) { //request rl_printf("Requesting Connection \r\n"); char cmdstring[] = "connect D1:83:15:3C:26:F0 random"; parse_line((char *) &cmdstring); } else { //wait for connection to be established usleep(1000); } } if (conn_state == STATE_CONNECTED) { // We are connected //if not connected if (!requested_read) { rl_printf("Requesting Reading\r\n"); //request read char cmdstring[] = "char-read-uuid 2a5b"; parse_line((char *) &cmdstring); requested_read = 1; } else { //wait until values are read usleep(1000); } } if (done_read) { rl_printf("Done Reading. Disconnecting\r\n"); char cmdstring[] = "disconnect"; parse_line((char *) &cmdstring); //Reset values requested_read = 0; done_read = 0; rl_printf("Loop is %d\r\n",loop_counter); loop_counter += 1; } return 1; } int main(int argc, char *argv[]) { guint input; guint signal; opt_sec_level = g_strdup("low"); // opt_src = g_strdup(src); // opt_dst = g_strdup(dst); // opt_dst_type = g_strdup(dst_type); // opt_psm = psm; conn_state = STATE_DISCONNECTED; prompt = g_string_new(NULL); event_loop = g_main_loop_new(NULL, FALSE); input = setup_standard_input(); signal = setup_signalfd(); requested_read = 0; done_read = 0; loop_counter = 0; g_timeout_add(1, (GSourceFunc) callback_fastloop, NULL); g_main_loop_run(event_loop); rl_callback_handler_remove(); cmd_disconnect(0, NULL); g_source_remove(input); g_source_remove(signal); g_main_loop_unref(event_loop); g_string_free(prompt, TRUE); g_free(opt_src); g_free(opt_dst); g_free(opt_sec_level); return 0; }