判断是否是哨兵模式

c
    char *exec_name = strrchr(argv[0], '/');
    if (exec_name == NULL) exec_name = argv[0];
    server.sentinel_mode = checkForSentinelMode(argc,argv, exec_name);
    initServerConfig();
    ACLInit(); /* The ACL subsystem must be initialized ASAP because the
                  basic networking code and client creation depends on it. */
    moduleInitModulesSystem();
    connTypeInitialize();
    ***********************************************************、
    
    


/* Returns 1 if there is --sentinel among the arguments or if
 * executable name contains "redis-sentinel". */
int checkForSentinelMode(int argc, char **argv, char *exec_name) {
    if (strstr(exec_name,"redis-sentinel") != NULL) return 1;

    for (int j = 1; j < argc; j++)
        if (!strcmp(argv[j],"--sentinel")) return 1;
    return 0;
}

初始化哨兵模式

c
/* This function overwrites a few normal Redis config default with Sentinel
 * specific defaults. */
void initSentinelConfig(void) {
    server.port = REDIS_SENTINEL_PORT;
    server.protected_mode = 0; /* Sentinel must be exposed. */
}

void freeSentinelLoadQueueEntry(void *item);

/* Perform the Sentinel mode initialization. */
void initSentinel(void) {
    /* Initialize various data structures. */
    sentinel.current_epoch = 0;
    sentinel.masters = dictCreate(&instancesDictType);
    sentinel.tilt = 0;
    sentinel.tilt_start_time = 0;
    sentinel.previous_time = mstime();
    sentinel.running_scripts = 0;
    sentinel.scripts_queue = listCreate();
    sentinel.announce_ip = NULL;
    sentinel.announce_port = 0;
    sentinel.simfailure_flags = SENTINEL_SIMFAILURE_NONE;
    sentinel.deny_scripts_reconfig = SENTINEL_DEFAULT_DENY_SCRIPTS_RECONFIG;
    sentinel.sentinel_auth_pass = NULL;
    sentinel.sentinel_auth_user = NULL;
    sentinel.resolve_hostnames = SENTINEL_DEFAULT_RESOLVE_HOSTNAMES;
    sentinel.announce_hostnames = SENTINEL_DEFAULT_ANNOUNCE_HOSTNAMES;
    memset(sentinel.myid,0,sizeof(sentinel.myid));
    server.sentinel_config = NULL;
}

c
/* Main state. */
struct sentinelState {
    char myid[CONFIG_RUN_ID_SIZE+1]; /* This sentinel ID. */
    uint64_t current_epoch;         /* Current epoch. */
    dict *masters;      /* Dictionary of master sentinelRedisInstances.
                           Key is the instance name, value is the
                           sentinelRedisInstance structure pointer. */
    int tilt;           /* Are we in TILT mode? */
    int running_scripts;    /* Number of scripts in execution right now. */
    mstime_t tilt_start_time;       /* When TITL started. */
    mstime_t previous_time;         /* Last time we ran the time handler. */
    list *scripts_queue;            /* Queue of user scripts to execute. */
    char *announce_ip;  /* IP addr that is gossiped to other sentinels if
                           not NULL. */
    int announce_port;  /* Port that is gossiped to other sentinels if
                           non zero. */
    unsigned long simfailure_flags; /* Failures simulation. */
    int deny_scripts_reconfig; /* Allow SENTINEL SET ... to change script
                                  paths at runtime? */
    char *sentinel_auth_pass;    /* Password to use for AUTH against other sentinel */
    char *sentinel_auth_user;    /* Username for ACLs AUTH against other sentinel. */
    int resolve_hostnames;       /* Support use of hostnames, assuming DNS is well configured. */
    int announce_hostnames;      /* Announce hostnames instead of IPs when we have them. */
} sentinel;

解析sentinel.conf

loadServerConfig