Android ADB实现解析【转】
本文转载自:http://blog.csdn.net/u010223349/article/details/41120255
ADB是Android系统提供的调试工具,整个ADB工具由三部分组成:adb client、adb service、adb daemon。
1、ADB client提供HOST端运行的命令2、ADB serviceHOST端上的一个后台进程3、ADB daemomDEVICE端(真实的机器或者模拟器)的守护进程
ADB代码位于/system/core/adb目录下,通过查看Android.mk,可以知道,该目录下的代码生成了两个MODULE,分别是adb和adbd, adb client和adb service都是由adb这个可执行文件实现, adb daemon由adbd实现。adb和adbd的一些源代码文件是用同一个的,编译时通过LOCAL_CFLAGS的参数ADB_HOST来区分,这种你中有我我中有你的关系,对于初次接触的朋友们,多少增加了些困扰。理清了ADB几部分的关系,以及源代码的结构,对ADB的认识已经有一个飞越了。
二、adb_main()函数
其中,adb daemon端代码如下,
一、main函数
adb.c的main函数是adb client、adb service、adb daemon的共同入口,
- int main(int argc, char **argv)
- {
- #if ADB_HOST
- adb_sysdeps_init();
- adb_trace_init();
- D("Handling commandline()\n");
- return adb_commandline(argc - 1, argv + 1);
- #else
- /* If adbd runs inside the emulator this will enable adb tracing via
- * adb-debug qemud service in the emulator. */
- adb_qemu_trace_init();
- if((argc > 1) && (!strcmp(argv[1],"recovery"))) {
- adb_device_banner = "recovery";
- recovery_mode = 1;
- }
- start_device_log();
- D("Handling main()\n");
- return adb_main(0, DEFAULT_ADB_PORT);
- #endif
- }
根据Android.mk中传入的ADB_HOST确定编译的是adb client\adb service, 或者是adb daemon, ADB_HOST为1时编译adb client\adb service的代码, ADB_HOST为0时编译adb daemon的代码。
以上代码中,adb client\adb service端代码如下,
- adb_sysdeps_init();
- adb_trace_init();
- D("Handling commandline()\n");
- return adb_commandline(argc - 1, argv + 1);
1、adb_sysdeps_init(): adb client\adb service适用于linux和windows版本,所以代码中有平台相关的部分。
2、adb_trace_init(): 初始化log输出配置,初始化后在HOST上设置ADB_TRACE这个环境变量,可以控制client\service端的log输出等级,
配置为1或者all的话,将输出所有 的log。
3、adb_commandline(): 关键函数,代码如下。
- int adb_commandline(int argc, char **argv)
- {
- char buf[4096];
- int no_daemon = 0;
- int is_daemon = 0;
- int is_server = 0;
- int persist = 0;
- int r;
- int quote;
- transport_type ttype = kTransportAny;
- char* serial = NULL;
- char* server_port_str = NULL;
- /* If defined, this should be an absolute path to
- * the directory containing all of the various system images
- * for a particular product. If not defined, and the adb
- * command requires this information, then the user must
- * specify the path using "-p".
- */
- gProductOutPath = getenv("ANDROID_PRODUCT_OUT");
- if (gProductOutPath == NULL || gProductOutPath[0] == '\0') {
- gProductOutPath = NULL;
- }
- // TODO: also try TARGET_PRODUCT/TARGET_DEVICE as a hint
- serial = getenv("ANDROID_SERIAL");
- /* Validate and assign the server port */
- server_port_str = getenv("ANDROID_ADB_SERVER_PORT");
- int server_port = DEFAULT_ADB_PORT;
- if (server_port_str && strlen(server_port_str) > 0) {
- server_port = (int) strtol(server_port_str, NULL, 0);
- if (server_port <= 0 || server_port > 65535) {
- fprintf(stderr,
- "adb: Env var ANDROID_ADB_SERVER_PORT must be a positive number less than 65535. Got \"%s\"\n",
- server_port_str);
- return usage();
- }
- }
- /* modifiers and flags */
- while(argc > 0) {
- if(!strcmp(argv[0],"server")) {
- is_server = 1;
- } else if(!strcmp(argv[0],"nodaemon")) {
- no_daemon = 1;
- } else if (!strcmp(argv[0], "fork-server")) {
- /* this is a special flag used only when the ADB client launches the ADB Server */
- is_daemon = 1;
- } else if(!strcmp(argv[0],"persist")) {
- persist = 1;
- } else if(!strncmp(argv[0], "-p", 2)) {
- const char *product = NULL;
- if (argv[0][2] == '\0') {
- if (argc < 2) return usage();
- product = argv[1];
- argc--;
- argv++;
- } else {
- product = argv[0] + 2;
- }
- gProductOutPath = find_product_out_path(product);
- if (gProductOutPath == NULL) {
- fprintf(stderr, "adb: could not resolve \"-p %s\"\n",
- product);
- return usage();
- }
- } else if (argv[0][0]=='-' && argv[0][1]=='s') {
- if (isdigit(argv[0][2])) {
- serial = argv[0] + 2;
- } else {
- if(argc < 2 || argv[0][2] != '\0') return usage();
- serial = argv[1];
- argc--;
- argv++;
- }
- } else if (!strcmp(argv[0],"-d")) {
- ttype = kTransportUsb;
- } else if (!strcmp(argv[0],"-e")) {
- ttype = kTransportLocal;
- } else if (!strcmp(argv[0],"-a")) {
- gListenAll = 1;
- } else if(!strncmp(argv[0], "-H", 2)) {
- const char *hostname = NULL;
- if (argv[0][2] == '\0') {
- if (argc < 2) return usage();
- hostname = argv[1];
- argc--;
- argv++;
- } else {
- hostname = argv[0] + 2;
- }
- adb_set_tcp_name(hostname);
- } else if(!strncmp(argv[0], "-P", 2)) {
- if (argv[0][2] == '\0') {
- if (argc < 2) return usage();
- server_port_str = argv[1];
- argc--;
- argv++;
- } else {
- server_port_str = argv[0] + 2;
- }
- if (strlen(server_port_str) > 0) {
- server_port = (int) strtol(server_port_str, NULL, 0);
- if (server_port <= 0 || server_port > 65535) {
- fprintf(stderr,
- "adb: port number must be a positive number less than 65536. Got \"%s\"\n",
- server_port_str);
- return usage();
- }
- } else {
- fprintf(stderr,
- "adb: port number must be a positive number less than 65536. Got empty string.\n");
- return usage();
- }
- } else {
- /* out of recognized modifiers and flags */
- break;
- }
- argc--;
- argv++;
- }
- adb_set_transport(ttype, serial);
- adb_set_tcp_specifics(server_port);
- if (is_server) {
- if (no_daemon || is_daemon) {
- r = adb_main(is_daemon, server_port);
- } else {
- r = launch_server(server_port);
- }
- if(r) {
- fprintf(stderr,"* could not start server *\n");
- }
- return r;
- }
- top:
- if(argc == 0) {
- return usage();
- }
- /* adb_connect() commands */
- if(!strcmp(argv[0], "devices")) {
- char *tmp;
- char *listopt;
- if (argc < 2)
- listopt = "";
- else if (argc == 2 && !strcmp(argv[1], "-l"))
- listopt = argv[1];
- else {
- fprintf(stderr, "Usage: adb devices [-l]\n");
- return 1;
- }
- snprintf(buf, sizeof buf, "host:%s%s", argv[0], listopt);
- tmp = adb_query(buf);
- if(tmp) {
- printf("List of devices attached \n");
- printf("%s\n", tmp);
- return 0;
- } else {
- return 1;
- }
- }
- if(!strcmp(argv[0], "connect")) {
- char *tmp;
- if (argc != 2) {
- fprintf(stderr, "Usage: adb connect <host>[:<port>]\n");
- return 1;
- }
- snprintf(buf, sizeof buf, "host:connect:%s", argv[1]);
- tmp = adb_query(buf);
- if(tmp) {
- printf("%s\n", tmp);
- return 0;
- } else {
- return 1;
- }
- }
- if(!strcmp(argv[0], "disconnect")) {
- char *tmp;
- if (argc > 2) {
- fprintf(stderr, "Usage: adb disconnect [<host>[:<port>]]\n");
- return 1;
- }
- if (argc == 2) {
- snprintf(buf, sizeof buf, "host:disconnect:%s", argv[1]);
- } else {
- snprintf(buf, sizeof buf, "host:disconnect:");
- }
- tmp = adb_query(buf);
- if(tmp) {
- printf("%s\n", tmp);
- return 0;
- } else {
- return 1;
- }
- }
- if (!strcmp(argv[0], "emu")) {
- return adb_send_emulator_command(argc, argv);
- }
- if(!strcmp(argv[0], "shell") || !strcmp(argv[0], "hell")) {
- int r;
- int fd;
- char h = (argv[0][0] == 'h');
- if (h) {
- printf("\x1b[41;33m");
- fflush(stdout);
- }
- if(argc < 2) {
- D("starting interactive shell\n");
- r = interactive_shell();
- if (h) {
- printf("\x1b[0m");
- fflush(stdout);
- }
- return r;
- }
- snprintf(buf, sizeof buf, "shell:%s", argv[1]);
- argc -= 2;
- argv += 2;
- while(argc-- > 0) {
- strcat(buf, " ");
- /* quote empty strings and strings with spaces */
- quote = (**argv == 0 || strchr(*argv, ' '));
- if (quote)
- strcat(buf, "\"");
- strcat(buf, *argv++);
- if (quote)
- strcat(buf, "\"");
- }
- for(;;) {
- D("interactive shell loop. buff=%s\n", buf);
- fd = adb_connect(buf);
- if(fd >= 0) {
- D("about to read_and_dump(fd=%d)\n", fd);
- read_and_dump(fd);
- D("read_and_dump() done.\n");
- adb_close(fd);
- r = 0;
- } else {
- fprintf(stderr,"error: %s\n", adb_error());
- r = -1;
- }
- if(persist) {
- fprintf(stderr,"\n- waiting for device -\n");
- adb_sleep_ms(1000);
- do_cmd(ttype, serial, "wait-for-device", 0);
- } else {
- if (h) {
- printf("\x1b[0m");
- fflush(stdout);
- }
- D("interactive shell loop. return r=%d\n", r);
- return r;
- }
- }
- }
- if(!strcmp(argv[0], "kill-server")) {
- int fd;
- fd = _adb_connect("host:kill");
- if(fd == -1) {
- fprintf(stderr,"* server not running *\n");
- return 1;
- }
- return 0;
- }
- if(!strcmp(argv[0], "sideload")) {
- if(argc != 2) return usage();
- if(adb_download("sideload", argv[1], 1)) {
- return 1;
- } else {
- return 0;
- }
- }
- if(!strcmp(argv[0], "remount") || !strcmp(argv[0], "reboot")
- || !strcmp(argv[0], "reboot-bootloader")
- || !strcmp(argv[0], "tcpip") || !strcmp(argv[0], "usb")
- || !strcmp(argv[0], "root")) {
- char command[100];
- if (!strcmp(argv[0], "reboot-bootloader"))
- snprintf(command, sizeof(command), "reboot:bootloader");
- else if (argc > 1)
- snprintf(command, sizeof(command), "%s:%s", argv[0], argv[1]);
- else
- snprintf(command, sizeof(command), "%s:", argv[0]);
- int fd = adb_connect(command);
- if(fd >= 0) {
- read_and_dump(fd);
- adb_close(fd);
- return 0;
- }
- fprintf(stderr,"error: %s\n", adb_error());
- return 1;
- }
- if(!strcmp(argv[0], "bugreport")) {
- if (argc != 1) return usage();
- do_cmd(ttype, serial, "shell", "bugreport", 0);
- return 0;
- }
- /* adb_command() wrapper commands */
- if(!strncmp(argv[0], "wait-for-", strlen("wait-for-"))) {
- char* service = argv[0];
- if (!strncmp(service, "wait-for-device", strlen("wait-for-device"))) {
- if (ttype == kTransportUsb) {
- service = "wait-for-usb";
- } else if (ttype == kTransportLocal) {
- service = "wait-for-local";
- } else {
- service = "wait-for-any";
- }
- }
- format_host_command(buf, sizeof buf, service, ttype, serial);
- if (adb_command(buf)) {
- D("failure: %s *\n",adb_error());
- fprintf(stderr,"error: %s\n", adb_error());
- return 1;
- }
- /* Allow a command to be run after wait-for-device,
- * e.g. 'adb wait-for-device shell'.
- */
- if(argc > 1) {
- argc--;
- argv++;
- goto top;
- }
- return 0;
- }
- if(!strcmp(argv[0], "forward")) {
- char host_prefix[64];
- char remove = 0;
- char remove_all = 0;
- char list = 0;
- char no_rebind = 0;
- // Parse options here.
- while (argc > 1 && argv[1][0] == '-') {
- if (!strcmp(argv[1], "--list"))
- list = 1;
- else if (!strcmp(argv[1], "--remove"))
- remove = 1;
- else if (!strcmp(argv[1], "--remove-all"))
- remove_all = 1;
- else if (!strcmp(argv[1], "--no-rebind"))
- no_rebind = 1;
- else {
- return usage();
- }
- argc--;
- argv++;
- }
- // Ensure we can only use one option at a time.
- if (list + remove + remove_all + no_rebind > 1) {
- return usage();
- }
- // Determine the <host-prefix> for this command.
- if (serial) {
- snprintf(host_prefix, sizeof host_prefix, "host-serial:%s",
- serial);
- } else if (ttype == kTransportUsb) {
- snprintf(host_prefix, sizeof host_prefix, "host-usb");
- } else if (ttype == kTransportLocal) {
- snprintf(host_prefix, sizeof host_prefix, "host-local");
- } else {
- snprintf(host_prefix, sizeof host_prefix, "host");
- }
- // Implement forward --list
- if (list) {
- if (argc != 1)
- return usage();
- snprintf(buf, sizeof buf, "%s:list-forward", host_prefix);
- char* forwards = adb_query(buf);
- if (forwards == NULL) {
- fprintf(stderr, "error: %s\n", adb_error());
- return 1;
- }
- printf("%s", forwards);
- free(forwards);
- return 0;
- }
- // Implement forward --remove-all
- else if (remove_all) {
- if (argc != 1)
- return usage();
- snprintf(buf, sizeof buf, "%s:killforward-all", host_prefix);
- }
- // Implement forward --remove <local>
- else if (remove) {
- if (argc != 2)
- return usage();
- snprintf(buf, sizeof buf, "%s:killforward:%s", host_prefix, argv[1]);
- }
- // Or implement one of:
- // forward <local> <remote>
- // forward --no-rebind <local> <remote>
- else
- {
- if (argc != 3)
- return usage();
- const char* command = no_rebind ? "forward:norebind:" : "forward";
- snprintf(buf, sizeof buf, "%s:%s:%s;%s", host_prefix, command, argv[1], argv[2]);
- }
- if(adb_command(buf)) {
- fprintf(stderr,"error: %s\n", adb_error());
- return 1;
- }
- return 0;
- }
- /* do_sync_*() commands */
- if(!strcmp(argv[0], "ls")) {
- if(argc != 2) return usage();
- return do_sync_ls(argv[1]);
- }
- if(!strcmp(argv[0], "push")) {
- if(argc != 3) return usage();
- return do_sync_push(argv[1], argv[2], 0 /* no verify APK */);
- }
- if(!strcmp(argv[0], "pull")) {
- if (argc == 2) {
- return do_sync_pull(argv[1], ".");
- } else if (argc == 3) {
- return do_sync_pull(argv[1], argv[2]);
- } else {
- return usage();
- }
- }
- if(!strcmp(argv[0], "install")) {
- if (argc < 2) return usage();
- return install_app(ttype, serial, argc, argv);
- }
- if(!strcmp(argv[0], "uninstall")) {
- if (argc < 2) return usage();
- return uninstall_app(ttype, serial, argc, argv);
- }
- if(!strcmp(argv[0], "sync")) {
- char *srcarg, *android_srcpath, *data_srcpath;
- int listonly = 0;
- int ret;
- if(argc < 2) {
- /* No local path was specified. */
- srcarg = NULL;
- } else if (argc >= 2 && strcmp(argv[1], "-l") == 0) {
- listonly = 1;
- if (argc == 3) {
- srcarg = argv[2];
- } else {
- srcarg = NULL;
- }
- } else if(argc == 2) {
- /* A local path or "android"/"data" arg was specified. */
- srcarg = argv[1];
- } else {
- return usage();
- }
- ret = find_sync_dirs(srcarg, &android_srcpath, &data_srcpath);
- if(ret != 0) return usage();
- if(android_srcpath != NULL)
- ret = do_sync_sync(android_srcpath, "/system", listonly);
- if(ret == 0 && data_srcpath != NULL)
- ret = do_sync_sync(data_srcpath, "/data", listonly);
- free(android_srcpath);
- free(data_srcpath);
- return ret;
- }
- /* passthrough commands */
- if(!strcmp(argv[0],"get-state") ||
- !strcmp(argv[0],"get-serialno") ||
- !strcmp(argv[0],"get-devpath"))
- {
- char *tmp;
- format_host_command(buf, sizeof buf, argv[0], ttype, serial);
- tmp = adb_query(buf);
- if(tmp) {
- printf("%s\n", tmp);
- return 0;
- } else {
- return 1;
- }
- }
- /* other commands */
- if(!strcmp(argv[0],"status-window")) {
- status_window(ttype, serial);
- return 0;
- }
- if(!strcmp(argv[0],"logcat") || !strcmp(argv[0],"lolcat") || !strcmp(argv[0],"longcat")) {
- return logcat(ttype, serial, argc, argv);
- }
- if(!strcmp(argv[0],"ppp")) {
- return ppp(argc, argv);
- }
- if (!strcmp(argv[0], "start-server")) {
- return adb_connect("host:start-server");
- }
- if (!strcmp(argv[0], "backup")) {
- return backup(argc, argv);
- }
- if (!strcmp(argv[0], "restore")) {
- return restore(argc, argv);
- }
- if (!strcmp(argv[0], "jdwp")) {
- int fd = adb_connect("jdwp");
- if (fd >= 0) {
- read_and_dump(fd);
- adb_close(fd);
- return 0;
- } else {
- fprintf(stderr, "error: %s\n", adb_error());
- return -1;
- }
- }
- /* "adb /?" is a common idiom under Windows */
- if(!strcmp(argv[0], "help") || !strcmp(argv[0], "/?")) {
- help();
- return 0;
- }
- if(!strcmp(argv[0], "version")) {
- version(stdout);
- return 0;
- }
- usage();
- return 1;
- }
adb_commandline解析adb命令,如adb devices, 关于某个命令具体执行过程,后面专门针对某个命令进行解析。
main()中, adbd端代码如下,
- /* If adbd runs inside the emulator this will enable adb tracing via
- * adb-debug qemud service in the emulator. */
- adb_qemu_trace_init();
- if((argc > 1) && (!strcmp(argv[1],"recovery"))) {
- adb_device_banner = "recovery";
- recovery_mode = 1;
- }
- start_device_log();
- D("Handling main()\n");
- return adb_main(0, DEFAULT_ADB_PORT);
1、adb_qemu_trace_init(): 建立和模拟器中的adb-debug qemud service的连接。
2、if((argc > 1) && (!strcmp(argv[1],"recovery"))) {
adb_device_banner = "recovery";
recovery_mode = 1;
}
recovery_mode = 1;
}
启动adbd的时候,可以加参数, 例如,在recovery模式中init.rc文件中的adbd service是带recovery参数的,如果带
recovery参数就设置这两个标志,但目前没有看到哪里用到了这两个标志。
3、start_device_log(): 配置adb daemon的log输出, 前面说了adb client和service端的log输出可以通过ADB_TRACE这个环境
变量来控制,adb daemon端的log可以通过persist.adb.trace_mask控制, start_device_log()中判persist.adb.trace_mask
的值,如果有值,就会将log输出到/data/adb/目录下。
4、adb_main():如下
- int adb_main(int is_daemon, int server_port)
- {
- #if !ADB_HOST
- int port;
- char value[PROPERTY_VALUE_MAX];
- umask(000);
- #endif
- atexit(adb_cleanup);
- #ifdef HAVE_WIN32_PROC
- SetConsoleCtrlHandler( ctrlc_handler, TRUE );
- #elif defined(HAVE_FORKEXEC)
- // No SIGCHLD. Let the service subproc handle its children.
- signal(SIGPIPE, SIG_IGN);
- #endif
- init_transport_registration();
- #if ADB_HOST
- HOST = 1;
- #ifdef WORKAROUND_BUG6558362
- if(is_daemon) adb_set_affinity();
- #endif
- usb_vendors_init();
- usb_init();
- local_init(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
- adb_auth_init();
- char local_name[30];
- build_local_name(local_name, sizeof(local_name), server_port);
- if(install_listener(local_name, "*smartsocket*", NULL, 0)) {
- exit(1);
- }
- #else
- property_get("ro.adb.secure", value, "0");
- auth_enabled = !strcmp(value, "1");
- if (auth_enabled)
- adb_auth_init();
- // Our external storage path may be different than apps, since
- // we aren't able to bind mount after dropping root.
- const char* adb_external_storage = getenv("ADB_EXTERNAL_STORAGE");
- if (NULL != adb_external_storage) {
- setenv("EXTERNAL_STORAGE", adb_external_storage, 1);
- } else {
- D("Warning: ADB_EXTERNAL_STORAGE is not set. Leaving EXTERNAL_STORAGE"
- " unchanged.\n");
- }
- /* don't listen on a port (default 5037) if running in secure mode */
- /* don't run as root if we are running in secure mode */
- if (should_drop_privileges()) {
- drop_capabilities_bounding_set_if_needed();
- /* add extra groups:
- ** AID_ADB to access the USB driver
- ** AID_LOG to read system logs (adb logcat)
- ** AID_INPUT to diagnose input issues (getevent)
- ** AID_INET to diagnose network issues (netcfg, ping)
- ** AID_GRAPHICS to access the frame buffer
- ** AID_NET_BT and AID_NET_BT_ADMIN to diagnose bluetooth (hcidump)
- ** AID_SDCARD_R to allow reading from the SD card
- ** AID_SDCARD_RW to allow writing to the SD card
- ** AID_MOUNT to allow unmounting the SD card before rebooting
- ** AID_NET_BW_STATS to read out qtaguid statistics
- */
- gid_t groups[] = { AID_ADB, AID_LOG, AID_INPUT, AID_INET, AID_GRAPHICS,
- AID_NET_BT, AID_NET_BT_ADMIN, AID_SDCARD_R, AID_SDCARD_RW,
- AID_MOUNT, AID_NET_BW_STATS };
- if (setgroups(sizeof(groups)/sizeof(groups[0]), groups) != 0) {
- exit(1);
- }
- /* then switch user and group to "shell" */
- if (setgid(AID_SHELL) != 0) {
- exit(1);
- }
- if (setuid(AID_SHELL) != 0) {
- exit(1);
- }
- D("Local port disabled\n");
- } else {
- char local_name[30];
- build_local_name(local_name, sizeof(local_name), server_port);
- if(install_listener(local_name, "*smartsocket*", NULL, 0)) {
- exit(1);
- }
- }
- int usb = 0;
- if (access(USB_ADB_PATH, F_OK) == 0 || access(USB_FFS_ADB_EP0, F_OK) == 0) {
- // listen on USB
- usb_init();
- usb = 1;
- }
- // If one of these properties is set, also listen on that port
- // If one of the properties isn't set and we couldn't listen on usb,
- // listen on the default port.
- property_get("service.adb.tcp.port", value, "");
- if (!value[0]) {
- property_get("persist.adb.tcp.port", value, "");
- }
- if (sscanf(value, "%d", &port) == 1 && port > 0) {
- printf("using port=%d\n", port);
- // listen on TCP port specified by service.adb.tcp.port property
- local_init(port);
- } else if (!usb) {
- // listen on default port
- local_init(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
- }
- D("adb_main(): pre init_jdwp()\n");
- init_jdwp();
- D("adb_main(): post init_jdwp()\n");
- #endif
- if (is_daemon)
- {
- // inform our parent that we are up and running.
- #ifdef HAVE_WIN32_PROC
- DWORD count;
- WriteFile( GetStdHandle( STD_OUTPUT_HANDLE ), "OK\n", 3, &count, NULL );
- #elif defined(HAVE_FORKEXEC)
- fprintf(stderr, "OK\n");
- #endif
- start_logging();
- }
- D("Event loop starting\n");
- fdevent_loop();
- usb_cleanup();
- return 0;
- }
二、adb_main()函数
上一节中已经附上adb_main()函数代码, 其中,adb service端的代码如下,
- usb_vendors_init();
- usb_init();
- local_init(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
- adb_auth_init();
- char local_name[30];
- build_local_name(local_name, sizeof(local_name), server_port);
- if(install_listener(local_name, "*smartsocket*", NULL, 0)) {
- exit(1);
- }
- .........
- start_logging();
- }
- D("Event loop starting\n");
- fdevent_loop();
- usb_cleanup();
1、usb_vendors_init(): 每个设备产家都会定义一个vender id来标识自己的usb 设备,ADB service端只会连接已知的vender
id,这个函数的作用就是初始化一个vender id的数组,初始化后这个数组中将包含adb代码中内建的一些产家的id以及HOST
端的android配置文件中定义的id。
2、usb_init(): 创建一个线程,线程处理函数device_poll_thread, 进入一个循环,每隔1s执行一次find_usb_device和
kick_disconnected_devices,find_usb_device搜索所有的usb设备,判断vender id是否在上面初始化的列表中,如果是,则
将该usb设备注册到一个handle_list中。调用register_usb_transport基于这个fd 构造一个atransport类型的对象,再基于
这个atransport对象调用register_transport构造一个tmsg类型的对象。
最后,将这个tmsg对象写到transport_registration_send这个fd, 将触发相应的socket监控。kick_disconnected_devices
判断adb设备是否还正常,不正常的话从handle_list中支掉。
3、local_init(): 创建一个线程,尝试连接HOST端5555-5585端口,如果连接成功,则返回一个fd, register_socket_transport
基于这个fd 构造一个atransport类型的对象,再基于这个atransport对象调用register_transport构造一个tmsg类型的
对象。最后,将这个tmsg对象写 transport_registration_send这个fd, 将触发相应的socket监控。
4、install_listener(): 监听"tcp:5037" , adb client与adb service之间通讯用这个端口。
5、start_logging(): 将stdin重写向到/dev/null, 将stdout、stderr重定向/tmp/adb.log, 然后输出"adb starting"到
stderr。
6、fdevent_loop(): 前面通过fdinstall()注册了几个fde, 这里就通过一个无限循环epoll相应的fd, 有相应的事件则调用
fdinstall时注册的处理函数。
7、usb_cleanup(): usb相关的清理工作,对应linux平台的实现目前为空。
其中,adb daemon端代码如下,
- property_get("ro.adb.secure", value, "0");
- auth_enabled = !strcmp(value, "1");
- if (auth_enabled)
- adb_auth_init();
- // Our external storage path may be different than apps, since
- // we aren't able to bind mount after dropping root.
- const char* adb_external_storage = getenv("ADB_EXTERNAL_STORAGE");
- if (NULL != adb_external_storage) {
- setenv("EXTERNAL_STORAGE", adb_external_storage, 1);
- } else {
- D("Warning: ADB_EXTERNAL_STORAGE is not set. Leaving EXTERNAL_STORAGE"
- " unchanged.\n");
- }
- /* don't listen on a port (default 5037) if running in secure mode */
- /* don't run as root if we are running in secure mode */
- if (should_drop_privileges()) {
- drop_capabilities_bounding_set_if_needed();
- /* add extra groups:
- ** AID_ADB to access the USB driver
- ** AID_LOG to read system logs (adb logcat)
- ** AID_INPUT to diagnose input issues (getevent)
- ** AID_INET to diagnose network issues (netcfg, ping)
- ** AID_GRAPHICS to access the frame buffer
- ** AID_NET_BT and AID_NET_BT_ADMIN to diagnose bluetooth (hcidump)
- ** AID_SDCARD_R to allow reading from the SD card
- ** AID_SDCARD_RW to allow writing to the SD card
- ** AID_MOUNT to allow unmounting the SD card before rebooting
- ** AID_NET_BW_STATS to read out qtaguid statistics
- */
- gid_t groups[] = { AID_ADB, AID_LOG, AID_INPUT, AID_INET, AID_GRAPHICS,
- AID_NET_BT, AID_NET_BT_ADMIN, AID_SDCARD_R, AID_SDCARD_RW,
- AID_MOUNT, AID_NET_BW_STATS };
- if (setgroups(sizeof(groups)/sizeof(groups[0]), groups) != 0) {
- exit(1);
- }
- /* then switch user and group to "shell" */
- if (setgid(AID_SHELL) != 0) {
- exit(1);
- }
- if (setuid(AID_SHELL) != 0) {
- exit(1);
- }
- D("Local port disabled\n");
- } else {
- char local_name[30];
- build_local_name(local_name, sizeof(local_name), server_port);
- if(install_listener(local_name, "*smartsocket*", NULL, 0)) {
- exit(1);
- }
- }
- int usb = 0;
- if (access(USB_ADB_PATH, F_OK) == 0 || access(USB_FFS_ADB_EP0, F_OK) == 0) {
- // listen on USB
- usb_init();
- usb = 1;
- }
- // If one of these properties is set, also listen on that port
- // If one of the properties isn't set and we couldn't listen on usb,
- // listen on the default port.
- property_get("service.adb.tcp.port", value, "");
- if (!value[0]) {
- property_get("persist.adb.tcp.port", value, "");
- }
- if (sscanf(value, "%d", &port) == 1 && port > 0) {
- printf("using port=%d\n", port);
- // listen on TCP port specified by service.adb.tcp.port property
- local_init(port);
- } else if (!usb) {
- // listen on default port
- local_init(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
- }
- D("adb_main(): pre init_jdwp()\n");
- init_jdwp();
- D("adb_main(): post init_jdwp()\n");
1、local_init(): adb daemon的这个函数与adb service端的有所不同,adb service端的local_init只在adb service初始化
的时候扫描一下5555-5585端口,而adb daemon端的local_init会在线程中运行一个无限循环,不停尝试连接5555端口或者由
service.adb.tcp.port\persist.adb.tcp.port设置的端口,因为作为daemon随时要准备为他人服务。
2、init_jdwp(): jdwp全称为java debug wire protocol, 每dalvik VM都会创建一个jdwp, 可以建立在adb或者tcp基础上,
与DDMS或debugger进行通信, 这个函数就是初始化了监听socket描述符"\0jdwp-control"动作。
adb daemon其它部分的代码与adb service都比较类似,可能参考adb service部分。