androidadb实现解析

Android ADB实现解析

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 service

HOST端上的一个后台进程

3、ADB daemom

DEVICE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。

一、main函数

adb.c的main函数是adb client、adb service、adb daemon的共同入口，

[cpp] view plaincopyint 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,

[cpp] view plaincopyadb_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。[cpp] view plaincopyint 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，

[cpp] view plaincopy/* 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;

}

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

[cpp] view plaincopyint 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 =