Redis源碼分析（三十三）--- redis-cli.c用戶端命令列介面的實現(2)

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         今天學習完了命令列用戶端的後續內容，整體感覺就是圍繞著2個東西轉，config和mode。為什麼我會這麼說呢，請繼續往下看，用戶端中的配置結構體和之前我們所學習的配置結構體，不是指的同一個概念，cli中的結構體除了基本的ip，Port連接埠號碼，還有就是各種mode的配置了。

/* Redis配置結構體 */static struct config {    char *hostip;    int hostport;    char *hostsocket;    long repeat;    long interval;    int dbnum;    int interactive;    int shutdown;    int monitor_mode;    int pubsub_mode;    int latency_mode;    int latency_history;    int cluster_mode;    int cluster_reissue_command;    int slave_mode;    int pipe_mode;    int pipe_timeout;    int getrdb_mode;    int stat_mode;    int scan_mode;    int intrinsic_latency_mode;    int intrinsic_latency_duration;    char *pattern;    char *rdb_filename;    int bigkeys;    int stdinarg; /* get last arg from stdin. (-x option) */    char *auth;    int output; /* output mode, see OUTPUT_* defines */    sds mb_delim;    char prompt[128];    char *eval;    int last_cmd_type;} config;

裡面少說也有10個mode模式了吧。我們先倒過來，看看cli的主程式啟動並執行流程，也就是main函數的執行步驟：

/*main函數主程式操作*/int main(int argc, char **argv) {    int firstarg;//首先初始化用戶端配置操作    config.hostip = sdsnew("127.0.0.1");    config.hostport = 6379;    config.hostsocket = NULL;    config.repeat = 1;    config.interval = 0;    config.dbnum = 0;    config.interactive = 0;    config.shutdown = 0;    config.monitor_mode = 0;    config.pubsub_mode = 0;    config.latency_mode = 0;    config.latency_history = 0;    config.cluster_mode = 0;    config.slave_mode = 0;    config.getrdb_mode = 0;    config.stat_mode = 0;    config.scan_mode = 0;    config.intrinsic_latency_mode = 0;    config.pattern = NULL;    config.rdb_filename = NULL;    config.pipe_mode = 0;    config.pipe_timeout = REDIS_CLI_DEFAULT_PIPE_TIMEOUT;    config.bigkeys = 0;    config.stdinarg = 0;    config.auth = NULL;    config.eval = NULL;    config.last_cmd_type = -1;    if (!isatty(fileno(stdout)) && (getenv("FAKETTY") == NULL))        config.output = OUTPUT_RAW;    else        config.output = OUTPUT_STANDARD;    config.mb_delim = sdsnew("\n");    cliInitHelp();//根據使用者輸入的參數，配置config    firstarg = parseOptions(argc,argv);    argc -= firstarg;    argv += firstarg;//配置設定完畢，根據配置中的模式設定，調用相應的mode方法    /* Latency mode */    if (config.latency_mode) {        if (cliConnect(0) == REDIS_ERR) exit(1);        latencyMode();    }    /* Slave mode */    if (config.slave_mode) {        if (cliConnect(0) == REDIS_ERR) exit(1);        slaveMode();    }....

後面的代碼與此相同，所以就省略了，步驟簡單來說，就是設定配置，根據配置啟動相應的模式，下面說說，裡面的主要幾種模式

1.statMode:

/* statMode主要輸出一些讀取資料統計的一些資訊 */static void statMode(void) {    redisReply *reply;    long aux, requests = 0;    int i = 0;    while(1) {        char buf[64];        int j;        reply = reconnectingInfo();        if (reply->type == REDIS_REPLY_ERROR) {            printf("ERROR: %s\n", reply->str);            exit(1);        }        if ((i++ % 20) == 0) {            printf("------- data ------ --------------------- load -------------------- - child -\n""keys       mem      clients blocked requests            connections          \n");        }        /* Keys */        aux = 0;        for (j = 0; j < 20; j++) {            long k;            sprintf(buf,"db%d:keys",j);            k = getLongInfoField(reply->str,buf);            if (k == LONG_MIN) continue;            aux += k;        }        sprintf(buf,"%ld",aux);        printf("%-11s",buf);        /* Used memory */        aux = getLongInfoField(reply->str,"used_memory");        bytesToHuman(buf,aux);        printf("%-8s",buf);        /* Clients */        aux = getLongInfoField(reply->str,"connected_clients");        sprintf(buf,"%ld",aux);        printf(" %-8s",buf);        /* Blocked (BLPOPPING) Clients */        aux = getLongInfoField(reply->str,"blocked_clients");        sprintf(buf,"%ld",aux);        printf("%-8s",buf);....

用戶端當前的資料統計資訊。

2.latencyMode中會用到的測試硬體計算效能的方法:

/* This is just some computation the compiler can't optimize out. * Should run in less than 100-200 microseconds even using very * slow hardware. Runs in less than 10 microseconds in modern HW. *//* 普通的計算操作，測試硬體計算的速度快慢 */unsigned long compute_something_fast(void) {    unsigned char s[256], i, j, t;    int count = 1000, k;    unsigned long output = 0;    for (k = 0; k < 256; k++) s[k] = k;    i = 0;    j = 0;    while(count--) {        i++;        j = j + s[i];        t = s[i];        s[i] = s[j];        s[j] = t;        output += s[(s[i]+s[j])&255];    }    return output;}

協助命令的輸出文檔是由下面的函數輸出的:

/* 協助命令的輸出文檔 */static void usage(void) {    sds version = cliVersion();    fprintf(stderr,"redis-cli %s\n""\n""Usage: redis-cli [OPTIONS] [cmd [arg [arg ...]]]\n""  -h <hostname>      Server hostname (default: 127.0.0.1).\n""  -p <port>          Server port (default: 6379).\n""  -s <socket>        Server socket (overrides hostname and port).\n""  -a <password>      Password to use when connecting to the server.\n""  -r <repeat>        Execute specified command N times.\n""  -i <interval>      When -r is used, waits <interval> seconds per command.\n""                     It is possible to specify sub-second times like -i 0.1.\n""  -n <db>            Database number.\n""  -x                 Read last argument from STDIN.\n""  -d <delimiter>     Multi-bulk delimiter in for raw formatting (default: \\n).\n""  -c                 Enable cluster mode (follow -ASK and -MOVED redirections).\n""  --raw              Use raw formatting for replies (default when STDOUT is\n""                     not a tty).\n""  --no-raw           Force formatted output even when STDOUT is not a tty.\n""  --csv              Output in CSV format.\n""  --latency          Enter a special mode continuously sampling latency.\n""  --latency-history  Like --latency but tracking latency changes over time.\n""                     Default time interval is 15 sec. Change it using -i.\n""  --slave            Simulate a slave showing commands received from the master.\n""  --rdb <filename>   Transfer an RDB dump from remote server to local file.\n""  --pipe             Transfer raw Redis protocol from stdin to server.\n""  --pipe-timeout <n> In --pipe mode, abort with error if after sending all data.\n""                     no reply is received within <n> seconds.\n""                     Default timeout: %d. Use 0 to wait forever.\n""  --bigkeys          Sample Redis keys looking for big keys.\n""  --scan             List all keys using the SCAN command.\n""  --pattern <pat>    Useful with --scan to specify a SCAN pattern.\n""  --intrinsic-latency <sec> Run a test to measure intrinsic system latency.\n""                     The test will run for the specified amount of seconds.\n""  --eval <file>      Send an EVAL command using the Lua script at <file>.\n""  --help             Output this help and exit.\n""  --version          Output version and exit.\n""\n""Examples:\n""  cat /etc/passwd | redis-cli -x set mypasswd\n""  redis-cli get mypasswd\n""  redis-cli -r 100 lpush mylist x\n""  redis-cli -r 100 -i 1 info | grep used_memory_human:\n""  redis-cli --eval myscript.lua key1 key2 , arg1 arg2 arg3\n""  redis-cli --scan --pattern '*:12345*'\n""\n""  (Note: when using --eval the comma separates KEYS[] from ARGV[] items)\n""\n""When no command is given, redis-cli starts in interactive mode.\n""Type \"help\" in interactive mode for information on available commands.\n""\n",        version, REDIS_CLI_DEFAULT_PIPE_TIMEOUT);    sdsfree(version);    exit(1);}

在命令裡面，會由於2個概念，1個叫一般性的Command命令還有一個是CommandGroup命令組的概念，舉個例子，比如list，set等經常會用到的一些命令，後面可以接好多種參數的命令，屬性命令組命令，一般CONFIG GET，這種功能非常單一的命令我們就叫他為普通的命令，Dump,Exist啊等等這些命令都是普通的命令，CommandGroup的命令不是很多就下面這麼幾個:

/* 所有的命令組 */static char *commandGroups[] = {    "generic",    "string",    "list",    "set",    "sorted_set",    "hash",    "pubsub",    "transactions",    "connection",    "server",    "scripting",    "hyperloglog"};

也是最最常用的命令，在redis的系統中。

Redis源碼分析（三十三）--- redis-cli.c用戶端命令列介面的實現(2)