Android源码目录hardware/ril/libril中总共包含5个C/CPP文件，它们分别是ril_commands.h、ril_unsol_commands.h、ril_event.h、ril_event.cpp和ril.cpp。这篇文章主要分析ril.cpp文件。

我们可以将该文件划分为定义部分和实现部分，先来看定义部分：

#define LOG_TAG "RILC" #include <hardware_legacy/power.h> #include <telephony/ril.h> #include <telephony/ril_cdma_sms.h> #include <cutils/sockets.h> #include <cutils/jstring.h> #include <cutils/record_stream.h> #include <utils/Log.h> #include <utils/SystemClock.h> #include <pthread.h> #include <binder/Parcel.h> #include <cutils/jstring.h> #include <sys/types.h> #include <pwd.h> #include <stdio.h> #include <stdlib.h> #include <stdarg.h> #include <string.h> #include <unistd.h> #include <fcntl.h> #include <time.h> #include <errno.h> #include <assert.h> #include <ctype.h> #include <alloca.h> #include <sys/un.h> #include <assert.h> #include <netinet/in.h> #include <cutils/properties.h> #include <ril_event.h> namespace android { #define PHONE_PROCESS "radio" #define SOCKET_NAME_RIL "rild" #define SOCKET_NAME_RIL_DEBUG "rild-debug" #define ANDROID_WAKE_LOCK_NAME "radio-interface" #define PROPERTY_RIL_IMPL "gsm.version.ril-impl" // match with constant in RIL.java #define MAX_COMMAND_BYTES (8 * 1024) // Basically: memset buffers that the client library // shouldn't be using anymore in an attempt to find // memory usage issues sooner. #define MEMSET_FREED 1 // 常见的获取数组元素个数的方法 #define NUM_ELEMS(a) (sizeof (a) / sizeof (a)[0]) // 返回两数中较小者 #define MIN(a,b) ((a)<(b) ? (a) : (b)) /* 回复类型：经过请求的回复和未经请求的回复*/ #define RESPONSE_SOLICITED 0 #define RESPONSE_UNSOLICITED 1 /* Negative values for private RIL errno's */ #define RIL_ERRNO_INVALID_RESPONSE -1 // request, response, and unsolicited msg print macro // 即打印缓冲区printBuf的大小 #define PRINTBUF_SIZE 8096 // Enable RILC log #define RILC_LOG 0 #if RILC_LOG // 三个宏的调用顺序是startRequest - printRequest - closeRequest // 这样打印出来的请求命令将包含在（）中 #define startRequest sprintf(printBuf, "(") #define closeRequest sprintf(printBuf, "%s)", printBuf) #define printRequest(token, req) \ LOGD("[%04d]> %s %s", token, requestToString(req), printBuf) // 三个宏的调用顺序是startResponse - printResponse - closeResponse // 这样打印出来的回复信息将包含在｛｝中 #define startResponse sprintf(printBuf, "%s {", printBuf) #define closeResponse sprintf(printBuf, "%s}", printBuf) #define printResponse LOGD("%s", printBuf) #define clearPrintBuf printBuf[0] = 0 #define removeLastChar printBuf[strlen(printBuf)-1] = 0 #define appendPrintBuf(x...) sprintf(printBuf, x) #else #define startRequest #define closeRequest #define printRequest(token, req) #define startResponse #define closeResponse #define printResponse #define clearPrintBuf #define removeLastChar #define appendPrintBuf(x...) #endif // 唤醒类型：不唤醒，部分唤醒 enum WakeType {DONT_WAKE, WAKE_PARTIAL}; // "经过请求的回复"结构体定义：请求号，命令分发处理函数，返回结果响应函数 // 该结构体的取值见ril_commands.h文件 typedef struct { int requestNumber; void (*dispatchFunction) (Parcel &p, struct RequestInfo *pRI); int(*responseFunction) (Parcel &p, void *response, size_t responselen); } CommandInfo; //"未经请求的回复"结构体定义：请求号，事件响应函数，唤醒类型 // 该结构体的取值见ril_unsol_commands.h文件 typedef struct { int requestNumber; int (*responseFunction) (Parcel &p, void *response, size_t responselen); WakeType wakeType; } UnsolResponseInfo; // 请求信息结构体，封装CommandInfo，串成链表 typedef struct RequestInfo { int32_t token; //this is not RIL_Token CommandInfo *pCI; struct RequestInfo *p_next; char cancelled; char local; // responses to local commands do not go back to command process } RequestInfo; // 用户回调信息结构体 typedef struct UserCallbackInfo { RIL_TimedCallback p_callback; // 回调函数 void *userParam; // 回调函数的参数 struct ril_event event; // ril event struct UserCallbackInfo *p_next; // 指向下一个回调信息结构（链表形式） } UserCallbackInfo; /*******************************************************************/ // 初始化回调结构 RIL_RadioFunctions s_callbacks = {0, NULL, NULL, NULL, NULL, NULL}; static int s_registerCalled = 0; static pthread_t s_tid_dispatch; // 分发处理线程ID static pthread_t s_tid_reader; // 读者线程ID static int s_started = 0; // 文件描述符初始化 static int s_fdListen = -1; static int s_fdCommand = -1; static int s_fdDebug = -1; static int s_fdWakeupRead; static int s_fdWakeupWrite; // 5个相关的事件 static struct ril_event s_commands_event; static struct ril_event s_wakeupfd_event; static struct ril_event s_listen_event; static struct ril_event s_wake_timeout_event; static struct ril_event s_debug_event; static const struct timeval TIMEVAL_WAKE_TIMEOUT = {1,0}; // 初始化互斥量和条件变量 static pthread_mutex_t s_pendingRequestsMutex = PTHREAD_MUTEX_INITIALIZER; static pthread_mutex_t s_writeMutex = PTHREAD_MUTEX_INITIALIZER; static pthread_mutex_t s_startupMutex = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t s_startupCond = PTHREAD_COND_INITIALIZER; static pthread_mutex_t s_dispatchMutex = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t s_dispatchCond = PTHREAD_COND_INITIALIZER; static RequestInfo *s_pendingRequests = NULL; static RequestInfo *s_toDispatchHead = NULL; static RequestInfo *s_toDispatchTail = NULL; static UserCallbackInfo *s_last_wake_timeout_info = NULL; static void *s_lastNITZTimeData = NULL; static size_t s_lastNITZTimeDataSize; #if RILC_LOG static char printBuf[PRINTBUF_SIZE]; // 缓存打印信息的数组 #endif /*******************************************************************/ // dispatch*系列函数是基带处理器对应用处理器请求的处理函数 static void dispatchVoid (Parcel& p, RequestInfo *pRI); static void dispatchString (Parcel& p, RequestInfo *pRI); static void dispatchStrings (Parcel& p, RequestInfo *pRI); static void dispatchInts (Parcel& p, RequestInfo *pRI); static void dispatchDial (Parcel& p, RequestInfo *pRI); static void dispatchSIM_IO (Parcel& p, RequestInfo *pRI); static void dispatchCallForward(Parcel& p, RequestInfo *pRI); static void dispatchRaw(Parcel& p, RequestInfo *pRI); static void dispatchSmsWrite (Parcel &p, RequestInfo *pRI); static void dispatchCdmaSms(Parcel &p, RequestInfo *pRI); static void dispatchCdmaSmsAck(Parcel &p, RequestInfo *pRI); static void dispatchGsmBrSmsCnf(Parcel &p, RequestInfo *pRI); static void dispatchCdmaBrSmsCnf(Parcel &p, RequestInfo *pRI); static void dispatchRilCdmaSmsWriteArgs(Parcel &p, RequestInfo *pRI); // response*系列函数是应用处理器对基带处理器消息的响应函数 // 包括请求回复响应函数和事件响应函数 static int responseInts(Parcel &p, void *response, size_t responselen); static int responseStrings(Parcel &p, void *response, size_t responselen); static int responseString(Parcel &p, void *response, size_t responselen); static int responseVoid(Parcel &p, void *response, size_t responselen); static int responseCallList(Parcel &p, void *response, size_t responselen); static int responseSMS(Parcel &p, void *response, size_t responselen); static int responseSIM_IO(Parcel &p, void *response, size_t responselen); static int responseCallForwards(Parcel &p, void *response, size_t responselen); static int responseDataCallList(Parcel &p, void *response, size_t responselen); static int responseRaw(Parcel &p, void *response, size_t responselen); static int responseSsn(Parcel &p, void *response, size_t responselen); static int responseSimStatus(Parcel &p, void *response, size_t responselen); static int responseGsmBrSmsCnf(Parcel &p, void *response, size_t responselen); static int responseCdmaBrSmsCnf(Parcel &p, void *response, size_t responselen); static int responseCdmaSms(Parcel &p, void *response, size_t responselen); static int responseCellList(Parcel &p, void *response, size_t responselen); static int responseCdmaInformationRecords(Parcel &p,void *response, size_t responselen); static int responseRilSignalStrength(Parcel &p,void *response, size_t responselen); static int responseCallRing(Parcel &p, void *response, size_t responselen); static int responseCdmaSignalInfoRecord(Parcel &p,void *response, size_t responselen); static int responseCdmaCallWaiting(Parcel &p,void *response, size_t responselen); // 将数据结构信息转换成字符串输出 extern "C" const char * requestToString(int request); extern "C" const char * failCauseToString(RIL_Errno); extern "C" const char * callStateToString(RIL_CallState); extern "C" const char * radioStateToString(RIL_RadioState); #ifdef RIL_SHLIB extern "C" void RIL_onUnsolicitedResponse(int unsolResponse, void *data, size_t datalen); #endif static UserCallbackInfo * internalRequestTimedCallback (RIL_TimedCallback callback, void *param, const struct timeval *relativeTime); /** Index == requestNumber */ // 很不错的一个用法，由于数组元素太多，为了代码的整洁清晰， // 将数组元素的定义放在一个单独的头文件中，并用#include进来即可 static CommandInfo s_commands[] = { #include "ril_commands.h" }; static UnsolResponseInfo s_unsolResponses[] = { #include "ril_unsol_commands.h" };

To Be Continued