/* * Copyright (C) 2010 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* this implements a GPS hardware library for the Android emulator. * the following code should be built as a shared library that will be * placed into /system/lib/hw/gps.goldfish.so * * it will be loaded by the code in hardware/libhardware/hardware.c * which is itself called from android_location_GpsLocationProvider.cpp */ #include #include #include #include #include #include #define LOG_TAG "gps_qemu" #include #include #include #include /* the name of the qemud-controlled socket */ #define QEMU_CHANNEL_NAME "gps" #define GPS_DEBUG 0 #if GPS_DEBUG # define D(...) ALOGD(__VA_ARGS__) #else # define D(...) ((void)0) #endif /*****************************************************************/ /*****************************************************************/ /***** *****/ /***** N M E A T O K E N I Z E R *****/ /***** *****/ /*****************************************************************/ /*****************************************************************/ typedef struct { const char* p; const char* end; } Token; #define MAX_NMEA_TOKENS 16 typedef struct { int count; Token tokens[ MAX_NMEA_TOKENS ]; } NmeaTokenizer; static int nmea_tokenizer_init( NmeaTokenizer* t, const char* p, const char* end ) { int count = 0; char* q; // the initial '$' is optional if (p < end && p[0] == '$') p += 1; // remove trailing newline if (end > p && end[-1] == '\n') { end -= 1; if (end > p && end[-1] == '\r') end -= 1; } // get rid of checksum at the end of the sentecne if (end >= p+3 && end[-3] == '*') { end -= 3; } while (p < end) { const char* q = p; q = memchr(p, ',', end-p); if (q == NULL) q = end; if (q > p) { if (count < MAX_NMEA_TOKENS) { t->tokens[count].p = p; t->tokens[count].end = q; count += 1; } } if (q < end) q += 1; p = q; } t->count = count; return count; } static Token nmea_tokenizer_get( NmeaTokenizer* t, int index ) { Token tok; static const char* dummy = ""; if (index < 0 || index >= t->count) { tok.p = tok.end = dummy; } else tok = t->tokens[index]; return tok; } static int str2int( const char* p, const char* end ) { int result = 0; int len = end - p; for ( ; len > 0; len--, p++ ) { int c; if (p >= end) goto Fail; c = *p - '0'; if ((unsigned)c >= 10) goto Fail; result = result*10 + c; } return result; Fail: return -1; } static double str2float( const char* p, const char* end ) { int result = 0; int len = end - p; char temp[16]; if (len >= (int)sizeof(temp)) return 0.; memcpy( temp, p, len ); temp[len] = 0; return strtod( temp, NULL ); } /*****************************************************************/ /*****************************************************************/ /***** *****/ /***** N M E A P A R S E R *****/ /***** *****/ /*****************************************************************/ /*****************************************************************/ #define NMEA_MAX_SIZE 83 typedef struct { int pos; int overflow; int utc_year; int utc_mon; int utc_day; int utc_diff; GpsLocation fix; gps_location_callback callback; char in[ NMEA_MAX_SIZE+1 ]; } NmeaReader; static void nmea_reader_update_utc_diff( NmeaReader* r ) { time_t now = time(NULL); struct tm tm_local; struct tm tm_utc; long time_local, time_utc; gmtime_r( &now, &tm_utc ); localtime_r( &now, &tm_local ); time_local = tm_local.tm_sec + 60*(tm_local.tm_min + 60*(tm_local.tm_hour + 24*(tm_local.tm_yday + 365*tm_local.tm_year))); time_utc = tm_utc.tm_sec + 60*(tm_utc.tm_min + 60*(tm_utc.tm_hour + 24*(tm_utc.tm_yday + 365*tm_utc.tm_year))); r->utc_diff = time_utc - time_local; } static void nmea_reader_init( NmeaReader* r ) { memset( r, 0, sizeof(*r) ); r->pos = 0; r->overflow = 0; r->utc_year = -1; r->utc_mon = -1; r->utc_day = -1; r->callback = NULL; r->fix.size = sizeof(r->fix); nmea_reader_update_utc_diff( r ); } static void nmea_reader_set_callback( NmeaReader* r, gps_location_callback cb ) { r->callback = cb; if (cb != NULL && r->fix.flags != 0) { D("%s: sending latest fix to new callback", __FUNCTION__); r->callback( &r->fix ); r->fix.flags = 0; } } static int nmea_reader_update_time( NmeaReader* r, Token tok ) { int hour, minute; double seconds; struct tm tm; time_t fix_time; if (tok.p + 6 > tok.end) return -1; if (r->utc_year < 0) { // no date yet, get current one time_t now = time(NULL); gmtime_r( &now, &tm ); r->utc_year = tm.tm_year + 1900; r->utc_mon = tm.tm_mon + 1; r->utc_day = tm.tm_mday; } hour = str2int(tok.p, tok.p+2); minute = str2int(tok.p+2, tok.p+4); seconds = str2float(tok.p+4, tok.end); tm.tm_hour = hour; tm.tm_min = minute; tm.tm_sec = (int) seconds; tm.tm_year = r->utc_year - 1900; tm.tm_mon = r->utc_mon - 1; tm.tm_mday = r->utc_day; tm.tm_isdst = -1; fix_time = mktime( &tm ) + r->utc_diff; r->fix.timestamp = (long long)fix_time * 1000; return 0; } static int nmea_reader_update_date( NmeaReader* r, Token date, Token time ) { Token tok = date; int day, mon, year; if (tok.p + 6 != tok.end) { D("date not properly formatted: '%.*s'", tok.end-tok.p, tok.p); return -1; } day = str2int(tok.p, tok.p+2); mon = str2int(tok.p+2, tok.p+4); year = str2int(tok.p+4, tok.p+6) + 2000; if ((day|mon|year) < 0) { D("date not properly formatted: '%.*s'", tok.end-tok.p, tok.p); return -1; } r->utc_year = year; r->utc_mon = mon; r->utc_day = day; return nmea_reader_update_time( r, time ); } static double convert_from_hhmm( Token tok ) { double val = str2float(tok.p, tok.end); int degrees = (int)(floor(val) / 100); double minutes = val - degrees*100.; double dcoord = degrees + minutes / 60.0; return dcoord; } static int nmea_reader_update_latlong( NmeaReader* r, Token latitude, char latitudeHemi, Token longitude, char longitudeHemi ) { double lat, lon; Token tok; tok = latitude; if (tok.p + 6 > tok.end) { D("latitude is too short: '%.*s'", tok.end-tok.p, tok.p); return -1; } lat = convert_from_hhmm(tok); if (latitudeHemi == 'S') lat = -lat; tok = longitude; if (tok.p + 6 > tok.end) { D("longitude is too short: '%.*s'", tok.end-tok.p, tok.p); return -1; } lon = convert_from_hhmm(tok); if (longitudeHemi == 'W') lon = -lon; r->fix.flags |= GPS_LOCATION_HAS_LAT_LONG; r->fix.latitude = lat; r->fix.longitude = lon; return 0; } static int nmea_reader_update_altitude( NmeaReader* r, Token altitude, Token units ) { double alt; Token tok = altitude; if (tok.p >= tok.end) return -1; r->fix.flags |= GPS_LOCATION_HAS_ALTITUDE; r->fix.altitude = str2float(tok.p, tok.end); return 0; } static int nmea_reader_update_bearing( NmeaReader* r, Token bearing ) { double alt; Token tok = bearing; if (tok.p >= tok.end) return -1; r->fix.flags |= GPS_LOCATION_HAS_BEARING; r->fix.bearing = str2float(tok.p, tok.end); return 0; } static int nmea_reader_update_speed( NmeaReader* r, Token speed ) { double alt; Token tok = speed; if (tok.p >= tok.end) return -1; r->fix.flags |= GPS_LOCATION_HAS_SPEED; r->fix.speed = str2float(tok.p, tok.end); return 0; } static void nmea_reader_parse( NmeaReader* r ) { /* we received a complete sentence, now parse it to generate * a new GPS fix... */ NmeaTokenizer tzer[1]; Token tok; D("Received: '%.*s'", r->pos, r->in); if (r->pos < 9) { D("Too short. discarded."); return; } nmea_tokenizer_init(tzer, r->in, r->in + r->pos); #if GPS_DEBUG { int n; D("Found %d tokens", tzer->count); for (n = 0; n < tzer->count; n++) { Token tok = nmea_tokenizer_get(tzer,n); D("%2d: '%.*s'", n, tok.end-tok.p, tok.p); } } #endif tok = nmea_tokenizer_get(tzer, 0); if (tok.p + 5 > tok.end) { D("sentence id '%.*s' too short, ignored.", tok.end-tok.p, tok.p); return; } // ignore first two characters. tok.p += 2; if ( !memcmp(tok.p, "GGA", 3) ) { // GPS fix Token tok_time = nmea_tokenizer_get(tzer,1); Token tok_latitude = nmea_tokenizer_get(tzer,2); Token tok_latitudeHemi = nmea_tokenizer_get(tzer,3); Token tok_longitude = nmea_tokenizer_get(tzer,4); Token tok_longitudeHemi = nmea_tokenizer_get(tzer,5); Token tok_altitude = nmea_tokenizer_get(tzer,9); Token tok_altitudeUnits = nmea_tokenizer_get(tzer,10); nmea_reader_update_time(r, tok_time); nmea_reader_update_latlong(r, tok_latitude, tok_latitudeHemi.p[0], tok_longitude, tok_longitudeHemi.p[0]); nmea_reader_update_altitude(r, tok_altitude, tok_altitudeUnits); } else if ( !memcmp(tok.p, "GSA", 3) ) { // do something ? } else if ( !memcmp(tok.p, "RMC", 3) ) { Token tok_time = nmea_tokenizer_get(tzer,1); Token tok_fixStatus = nmea_tokenizer_get(tzer,2); Token tok_latitude = nmea_tokenizer_get(tzer,3); Token tok_latitudeHemi = nmea_tokenizer_get(tzer,4); Token tok_longitude = nmea_tokenizer_get(tzer,5); Token tok_longitudeHemi = nmea_tokenizer_get(tzer,6); Token tok_speed = nmea_tokenizer_get(tzer,7); Token tok_bearing = nmea_tokenizer_get(tzer,8); Token tok_date = nmea_tokenizer_get(tzer,9); D("in RMC, fixStatus=%c", tok_fixStatus.p[0]); if (tok_fixStatus.p[0] == 'A') { nmea_reader_update_date( r, tok_date, tok_time ); nmea_reader_update_latlong( r, tok_latitude, tok_latitudeHemi.p[0], tok_longitude, tok_longitudeHemi.p[0] ); nmea_reader_update_bearing( r, tok_bearing ); nmea_reader_update_speed ( r, tok_speed ); } } else { tok.p -= 2; D("unknown sentence '%.*s", tok.end-tok.p, tok.p); } if (r->fix.flags != 0) { #if GPS_DEBUG char temp[256]; char* p = temp; char* end = p + sizeof(temp); struct tm utc; p += snprintf( p, end-p, "sending fix" ); if (r->fix.flags & GPS_LOCATION_HAS_LAT_LONG) { p += snprintf(p, end-p, " lat=%g lon=%g", r->fix.latitude, r->fix.longitude); } if (r->fix.flags & GPS_LOCATION_HAS_ALTITUDE) { p += snprintf(p, end-p, " altitude=%g", r->fix.altitude); } if (r->fix.flags & GPS_LOCATION_HAS_SPEED) { p += snprintf(p, end-p, " speed=%g", r->fix.speed); } if (r->fix.flags & GPS_LOCATION_HAS_BEARING) { p += snprintf(p, end-p, " bearing=%g", r->fix.bearing); } if (r->fix.flags & GPS_LOCATION_HAS_ACCURACY) { p += snprintf(p,end-p, " accuracy=%g", r->fix.accuracy); } gmtime_r( (time_t*) &r->fix.timestamp, &utc ); p += snprintf(p, end-p, " time=%s", asctime( &utc ) ); D(temp); #endif if (r->callback) { r->callback( &r->fix ); r->fix.flags = 0; } else { D("no callback, keeping data until needed !"); } } } static void nmea_reader_addc( NmeaReader* r, int c ) { if (r->overflow) { r->overflow = (c != '\n'); return; } if (r->pos >= (int) sizeof(r->in)-1 ) { r->overflow = 1; r->pos = 0; return; } r->in[r->pos] = (char)c; r->pos += 1; if (c == '\n') { nmea_reader_parse( r ); r->pos = 0; } } /*****************************************************************/ /*****************************************************************/ /***** *****/ /***** C O N N E C T I O N S T A T E *****/ /***** *****/ /*****************************************************************/ /*****************************************************************/ /* commands sent to the gps thread */ enum { CMD_QUIT = 0, CMD_START = 1, CMD_STOP = 2 }; /* this is the state of our connection to the qemu_gpsd daemon */ typedef struct { int init; int fd; GpsCallbacks callbacks; pthread_t thread; int control[2]; } GpsState; static GpsState _gps_state[1]; static void gps_state_done( GpsState* s ) { // tell the thread to quit, and wait for it char cmd = CMD_QUIT; void* dummy; write( s->control[0], &cmd, 1 ); pthread_join(s->thread, &dummy); // close the control socket pair close( s->control[0] ); s->control[0] = -1; close( s->control[1] ); s->control[1] = -1; // close connection to the QEMU GPS daemon close( s->fd ); s->fd = -1; s->init = 0; } static void gps_state_start( GpsState* s ) { char cmd = CMD_START; int ret; do { ret=write( s->control[0], &cmd, 1 ); } while (ret < 0 && errno == EINTR); if (ret != 1) D("%s: could not send CMD_START command: ret=%d: %s", __FUNCTION__, ret, strerror(errno)); } static void gps_state_stop( GpsState* s ) { char cmd = CMD_STOP; int ret; do { ret=write( s->control[0], &cmd, 1 ); } while (ret < 0 && errno == EINTR); if (ret != 1) D("%s: could not send CMD_STOP command: ret=%d: %s", __FUNCTION__, ret, strerror(errno)); } static int epoll_register( int epoll_fd, int fd ) { struct epoll_event ev; int ret, flags; /* important: make the fd non-blocking */ flags = fcntl(fd, F_GETFL); fcntl(fd, F_SETFL, flags | O_NONBLOCK); ev.events = EPOLLIN; ev.data.fd = fd; do { ret = epoll_ctl( epoll_fd, EPOLL_CTL_ADD, fd, &ev ); } while (ret < 0 && errno == EINTR); return ret; } static int epoll_deregister( int epoll_fd, int fd ) { int ret; do { ret = epoll_ctl( epoll_fd, EPOLL_CTL_DEL, fd, NULL ); } while (ret < 0 && errno == EINTR); return ret; } /* this is the main thread, it waits for commands from gps_state_start/stop and, * when started, messages from the QEMU GPS daemon. these are simple NMEA sentences * that must be parsed to be converted into GPS fixes sent to the framework */ static void gps_state_thread( void* arg ) { GpsState* state = (GpsState*) arg; NmeaReader reader[1]; int epoll_fd = epoll_create(2); int started = 0; int gps_fd = state->fd; int control_fd = state->control[1]; nmea_reader_init( reader ); // register control file descriptors for polling epoll_register( epoll_fd, control_fd ); epoll_register( epoll_fd, gps_fd ); D("gps thread running"); // now loop for (;;) { struct epoll_event events[2]; int ne, nevents; nevents = epoll_wait( epoll_fd, events, 2, -1 ); if (nevents < 0) { if (errno != EINTR) ALOGE("epoll_wait() unexpected error: %s", strerror(errno)); continue; } D("gps thread received %d events", nevents); for (ne = 0; ne < nevents; ne++) { if ((events[ne].events & (EPOLLERR|EPOLLHUP)) != 0) { ALOGE("EPOLLERR or EPOLLHUP after epoll_wait() !?"); return; } if ((events[ne].events & EPOLLIN) != 0) { int fd = events[ne].data.fd; if (fd == control_fd) { char cmd = 255; int ret; D("gps control fd event"); do { ret = read( fd, &cmd, 1 ); } while (ret < 0 && errno == EINTR); if (cmd == CMD_QUIT) { D("gps thread quitting on demand"); return; } else if (cmd == CMD_START) { if (!started) { D("gps thread starting location_cb=%p", state->callbacks.location_cb); started = 1; nmea_reader_set_callback( reader, state->callbacks.location_cb ); } } else if (cmd == CMD_STOP) { if (started) { D("gps thread stopping"); started = 0; nmea_reader_set_callback( reader, NULL ); } } } else if (fd == gps_fd) { char buff[32]; D("gps fd event"); for (;;) { int nn, ret; ret = read( fd, buff, sizeof(buff) ); if (ret < 0) { if (errno == EINTR) continue; if (errno != EWOULDBLOCK) ALOGE("error while reading from gps daemon socket: %s:", strerror(errno)); break; } D("received %d bytes: %.*s", ret, ret, buff); for (nn = 0; nn < ret; nn++) nmea_reader_addc( reader, buff[nn] ); } D("gps fd event end"); } else { ALOGE("epoll_wait() returned unkown fd %d ?", fd); } } } } } static void gps_state_init( GpsState* state, GpsCallbacks* callbacks ) { state->init = 1; state->control[0] = -1; state->control[1] = -1; state->fd = -1; state->fd = qemud_channel_open(QEMU_CHANNEL_NAME); if (state->fd < 0) { D("no gps emulation detected"); return; } D("gps emulation will read from '%s' qemud channel", QEMU_CHANNEL_NAME ); if ( socketpair( AF_LOCAL, SOCK_STREAM, 0, state->control ) < 0 ) { ALOGE("could not create thread control socket pair: %s", strerror(errno)); goto Fail; } state->thread = callbacks->create_thread_cb( "gps_state_thread", gps_state_thread, state ); if ( !state->thread ) { ALOGE("could not create gps thread: %s", strerror(errno)); goto Fail; } state->callbacks = *callbacks; D("gps state initialized"); return; Fail: gps_state_done( state ); } /*****************************************************************/ /*****************************************************************/ /***** *****/ /***** I N T E R F A C E *****/ /***** *****/ /*****************************************************************/ /*****************************************************************/ static int qemu_gps_init(GpsCallbacks* callbacks) { GpsState* s = _gps_state; if (!s->init) gps_state_init(s, callbacks); if (s->fd < 0) return -1; return 0; } static void qemu_gps_cleanup(void) { GpsState* s = _gps_state; if (s->init) gps_state_done(s); } static int qemu_gps_start() { GpsState* s = _gps_state; if (!s->init) { D("%s: called with uninitialized state !!", __FUNCTION__); return -1; } D("%s: called", __FUNCTION__); gps_state_start(s); return 0; } static int qemu_gps_stop() { GpsState* s = _gps_state; if (!s->init) { D("%s: called with uninitialized state !!", __FUNCTION__); return -1; } D("%s: called", __FUNCTION__); gps_state_stop(s); return 0; } static int qemu_gps_inject_time(GpsUtcTime time, int64_t timeReference, int uncertainty) { return 0; } static int qemu_gps_inject_location(double latitude, double longitude, float accuracy) { return 0; } static void qemu_gps_delete_aiding_data(GpsAidingData flags) { } static int qemu_gps_set_position_mode(GpsPositionMode mode, int fix_frequency) { // FIXME - support fix_frequency return 0; } static const void* qemu_gps_get_extension(const char* name) { // no extensions supported return NULL; } static const GpsInterface qemuGpsInterface = { sizeof(GpsInterface), qemu_gps_init, qemu_gps_start, qemu_gps_stop, qemu_gps_cleanup, qemu_gps_inject_time, qemu_gps_inject_location, qemu_gps_delete_aiding_data, qemu_gps_set_position_mode, qemu_gps_get_extension, }; const GpsInterface* gps__get_gps_interface(struct gps_device_t* dev) { return &qemuGpsInterface; } static int open_gps(const struct hw_module_t* module, char const* name, struct hw_device_t** device) { struct gps_device_t *dev = malloc(sizeof(struct gps_device_t)); memset(dev, 0, sizeof(*dev)); dev->common.tag = HARDWARE_DEVICE_TAG; dev->common.version = 0; dev->common.module = (struct hw_module_t*)module; // dev->common.close = (int (*)(struct hw_device_t*))close_lights; dev->get_gps_interface = gps__get_gps_interface; *device = (struct hw_device_t*)dev; return 0; } static struct hw_module_methods_t gps_module_methods = { .open = open_gps }; struct hw_module_t HAL_MODULE_INFO_SYM = { .tag = HARDWARE_MODULE_TAG, .version_major = 1, .version_minor = 0, .id = GPS_HARDWARE_MODULE_ID, .name = "Goldfish GPS Module", .author = "The Android Open Source Project", .methods = &gps_module_methods, };