simple-dict/server.c

/* See feature_test_macros(7) */
#define _GNU_SOURCE 1
#include <arpa/inet.h>
#include <netinet/in.h>
#include <pthread.h>
#include <signal.h>
#include <simple_protobuf.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
#include "server.h"
#include "dict.h"
#include "crypto.h"
#include "config.h"

#if !__APPLE__
    #include <sys/sendfile.h>
#endif

#ifdef LISTEN_ON_IPV6
    static socklen_t struct_len = sizeof(struct sockaddr_in6);
    static struct sockaddr_in6 server_addr;
#else
    static socklen_t struct_len = sizeof(struct sockaddr_in);
    static struct sockaddr_in server_addr;
#endif

struct thread_timer_t {
    uint32_t index;
    int accept_fd;
    time_t touch;
    ssize_t numbytes;
    char *dat;
    pthread_t thread;
    uint8_t buf[BUFSIZ-sizeof(uint32_t)-sizeof(int)-sizeof(time_t)-sizeof(ssize_t)-sizeof(char*)-sizeof(pthread_t)];
};
typedef struct thread_timer_t thread_timer_t;
static thread_timer_t timers[THREADCNT];
#define timer_pointer_of(x) ((thread_timer_t*)(x))
#define touch_timer(x) (timer_pointer_of(x)->touch = time(NULL))

static dict_t setdicts[THREADCNT];
static uint32_t* items_len;
static CONFIG cfg;
static pthread_attr_t attr;

#define DICTPOOLSZ (((uint32_t)-1)>>((sizeof(uint32_t)*8-DICTPOOLBIT)))
static dict_t* dict_pool[DICTPOOLSZ+1];

static void accept_client(int fd);
static void accept_timer(void *p);
static int bind_server(uint16_t* port);
static void cleanup_thread(thread_timer_t* timer);
static server_ack_t del(FILE *fp, const char* key, int len, char ret[4]);
static void handle_accept(void *accept_fd_p);
static void handle_int(int signo);
static void handle_pipe(int signo);
static void handle_quit(int signo);
static void handle_segv(int signo);
static void init_dict_pool(FILE *fp);
static int insert_item(FILE *fp, const dict_t* dict, int keysize, int datasize);
static inline uint32_t last_nonnull(const char* p, uint32_t max_size);
static int listen_socket(int fd);
static int send_all(thread_timer_t *timer);
static int send_data(int accept_fd, int index, server_ack_t cmd, const char *data, size_t length);
static int s1_get(thread_timer_t *timer);
static int s2_set(thread_timer_t *timer);
static int s3_set_data(thread_timer_t *timer);
static int s4_del(thread_timer_t *timer);
static int s5_md5(thread_timer_t *timer);

static int bind_server(uint16_t* port) {
    #ifdef LISTEN_ON_IPV6
        server_addr.sin6_family = AF_INET6;
        server_addr.sin6_port = htons(*port);
        bzero(&(server_addr.sin6_addr), sizeof(server_addr.sin6_addr));
        int fd = socket(PF_INET6, SOCK_STREAM, 0);
    #else
        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(*port);
        server_addr.sin_addr.s_addr = INADDR_ANY;
        bzero(&(server_addr.sin_zero), 8);
        int fd = socket(AF_INET, SOCK_STREAM, 0);
    #endif
    if(!~bind(fd, (struct sockaddr *)&server_addr, struct_len)) {
        perror("Bind server failure");
        return 0;
    }
    #ifdef LISTEN_ON_IPV6
        *port = ntohs(server_addr.sin6_port);
        struct in6_addr in = server_addr.sin6_addr;
        char str[INET6_ADDRSTRLEN];	// 46
        inet_ntop(AF_INET6, &in, str, sizeof(str));
    #else
        *port = ntohs(server_addr.sin_port);
        struct in_addr in = server_addr.sin_addr;
        char str[INET_ADDRSTRLEN];	// 16
        inet_ntop(AF_INET, &in, str, sizeof(str));
    #endif
    printf("Bind server successfully on %s:%u\n", str, *port);
    return fd;
}

static int listen_socket(int fd) {
    if(!~listen(fd, THREADCNT)) {
        perror("Listen failed");
        return 0;
    }
    puts("Listening...");
    return fd;
}

static inline uint32_t last_nonnull(const char* p, uint32_t max_size) {
    if(max_size > 1) while(!p[max_size - 1]) max_size--;
    return max_size;
}

static int send_data(int accept_fd, int index, server_ack_t cmd, const char *data, size_t length) {
    char buf[CMDPACKET_LEN_MAX];
    cmdpacket_t p = (cmdpacket_t)buf;
    p->cmd = (uint8_t)cmd;
    p->datalen = length;
    memcpy(p->data, data, p->datalen);
    cmdpacket_encrypt(p, index, cfg.pwd);
    int total = CMDPACKET_HEAD_LEN+p->datalen;
    if(!~send(accept_fd, buf, total, 0)) {
        perror("Send data error");
        return 0;
    } else {
        printf("Send %d bytes data: ", total);
        for(int i = 0; i < length; i++) putchar(data[i]);
        putchar('\n');
        return 1;
    }
}

static int send_all(thread_timer_t *timer) {
    int re = 1;
    FILE *fp = open_dict(timer->index, 1);
    if(fp == NULL) return 1;
    pthread_cleanup_push((void*)&close_dict, (void*)(uintptr_t)timer->index);
    off_t len = 0, file_size = get_dict_size();
    char* buf = (char*)malloc(file_size);
    if(buf) {
        pthread_cleanup_push((void*)&free, (void*)buf);
        if(fread(buf, file_size, 1, fp) == 1) {
            #ifdef DEBUG
                printf("Get dict file size: %u\n", (unsigned int)file_size);
            #endif
            char* encbuf = raw_encrypt(buf, &file_size, timer->index, cfg.pwd);
            sprintf(timer->dat, "%u$", (unsigned int)file_size);
            //printf("Get encrypted file size: %s\n", timer->dat);
            //FILE* fp = fopen("raw_after_enc", "wb+");
            //fwrite(encbuf, file_size, 1, fp);
            //fclose(fp);
            pthread_cleanup_push((void*)&free, (void*)encbuf);
            if(send(timer->accept_fd, timer->dat, strlen(timer->dat), 0) > 0) {
                re = send(timer->accept_fd, encbuf, file_size, 0);
                printf("Send %u bytes.\n", re);
            } else re = 0;
            pthread_cleanup_pop(1);
        }
        pthread_cleanup_pop(1);
    }
    pthread_cleanup_pop(1);
    return re;
}

#define has_next(fp, ch) ((ch=getc(fp)),(feof(fp)?0:(ch?ungetc(ch,fp):1)))

static void init_dict_pool(FILE *fp) {
    uint8_t digest[16];
    uint8_t buf[8+DICTSZ];
    int ch;
    while(has_next(fp, ch)) {
        if(!ch) continue; // skip null bytes
        SIMPLE_PB* spb = read_pb_into(fp, (SIMPLE_PB*)buf);
        if(!spb) {
            fputs("Bad spb file", stderr);
            exit(EXIT_FAILURE);
        }
        dict_t* d = (dict_t*)spb->target;
        md5((uint8_t *)d->key, strlen(d->key)+1, digest);
        uint8_t* dp = digest;
        int p = ((*((uint32_t*)digest))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ;
        int c = 16-4;
        dict_t* slot;

        while((slot=dict_pool[p]) && c-->0) {
            #ifdef DEBUG
                printf("digest of %s: %08x got conflicted, remaining chance: %d.\n", d->key, p, c);
            #endif
            p = ((*((uint32_t*)(++dp)))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ; // 哈希碰撞
            #ifdef DEBUG
                printf("skip digest of %s to %08x.\n", d->key, p);
            #endif
        }
        #ifdef DEBUG
            if(slot) printf("cannot find any empty slot for digest of %s: %08x, drop it.\n", d->key, p);
        #endif

        if(!slot) {
            dict_t* dnew = (dict_t*)malloc(sizeof(dict_t));
            memcpy(dnew, d, sizeof(dict_t));
            dict_pool[p] = dnew; // 解决哈希冲突
        }
    }
}

static int s1_get(thread_timer_t *timer) {
    uint8_t digest[16];
    uint8_t buf[8+DICTSZ];
    if(require_shared_lock()) // busy
        return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);
    int ret = -1;

    pthread_cleanup_push((void*)&release_shared_lock, NULL);
    while(1) {
        md5((uint8_t*)timer->dat, strlen(timer->dat)+1, digest);
        uint8_t* dp = digest;
        int p = ((*((uint32_t*)digest))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ;
        if(!dict_pool[p]) {
            ret = send_data(timer->accept_fd, timer->index, ACKNULL, "null", 4); // 无值
            break;
        }

        int c = 16-4;
        int notok = 1;
        while(dict_pool[p] && (notok=strcmp(timer->dat, dict_pool[p]->key)) && c-->0) {
            #ifdef DEBUG
                printf("digest of %s: %08x got conflicted, remaining chance: %d.\n", timer->dat, p, c);
            #endif
            p = ((*((uint32_t*)(++dp)))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ; // 哈希碰撞
            #ifdef DEBUG
                printf("skip digest of %s to %08x.\n", timer->dat, p);
            #endif
        }
        if(!notok) { // 找到值
            ret = send_data(timer->accept_fd, timer->index, ACKSUCC, dict_pool[p]->data, last_nonnull(dict_pool[p]->data, DICTDATSZ));
            break;
        }
        if(!dict_pool[p]) {
            ret = send_data(timer->accept_fd, timer->index, ACKNULL, "null", 4); // 无值
            break;
        }
        #ifdef DEBUG
            printf("cannot find any empty slot for digest of %s: %08x, open dict to find it.\n", timer->dat, p);
        #endif

        break;
    }
    pthread_cleanup_pop(1);
    if(~ret) return ret;

    FILE *fp = open_dict(timer->index, 1); // really open
    if(fp == NULL) return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);
    while(1) {
        int ch;
        pthread_cleanup_push((void*)&close_dict, (void*)(uintptr_t)timer->index);
        while(has_next(fp, ch)) {
            if(!ch) continue; // skip null bytes
            SIMPLE_PB* spb = read_pb_into(fp, (SIMPLE_PB*)buf);
            if(!spb) continue; // skip error bytes
            dict_t* d = (dict_t*)spb->target;
            if(!strcmp(timer->dat, d->key)) {
                ret = send_data(timer->accept_fd, timer->index, ACKSUCC, d->data, last_nonnull(d->data, DICTDATSZ));
                break;
            }
        }
        pthread_cleanup_pop(1);
        break;
    }

    if(!~ret) return send_data(timer->accept_fd, timer->index, ACKNULL, "null", 4);
    return ret;
}

static int s2_set(thread_timer_t *timer) {
    memset(&setdicts[timer->index], 0, sizeof(dict_t));
    strncpy(setdicts[timer->index].key, timer->dat, DICTKEYSZ-1);
    md5((uint8_t*)timer->dat, strlen(timer->dat)+1, (uint8_t*)setdicts[timer->index].data);
    return send_data(timer->accept_fd, timer->index, ACKDATA, "data", 4);
}

static int insert_item(FILE *fp, const dict_t* dict, int keysize, int datasize) {
    int ch;
    const char* key = dict->key;
    const char* data = dict->data;
    uint8_t buf[8+DICTSZ];
    while(has_next(fp, ch)) {
        if(!ch) continue; // skip null bytes
        SIMPLE_PB* spb = read_pb_into(fp, (SIMPLE_PB*)buf);
        if(!spb) {
            fputs("Bad spb file", stderr);
            pthread_exit(NULL);
        }
        dict_t* d = (dict_t*)spb->target;
        if(memcmp(key, d->key, keysize)) continue;
        int datalen = last_nonnull(d->data, DICTDATSZ);
        if(datalen == datasize) { // 新增 data 可以直接覆盖到原 data
            if(fseek(fp, -(int)(spb->real_len), SEEK_CUR)) goto ERR_INSERT_ITEM;
            goto TRY_INSERT_ITEM;
        }
        uint32_t next = ftell(fp);
        uint32_t this = next - spb->real_len;
        if(fseek(fp, 0, SEEK_END)) goto ERR_INSERT_ITEM;
        uint32_t end = ftell(fp);
        if(next == end) {
            if(!ftruncate(fileno(fp), end - spb->real_len)) {
                if(fseek(fp, 0, SEEK_END)) goto ERR_INSERT_ITEM;
                goto TRY_INSERT_ITEM;
            }
            goto ERR_INSERT_ITEM;
        }
        uint32_t cap = end - next;
        #ifdef DEBUG
            printf("this: %u, next: %u, end: %u, cap: %u\n", this, next, end, cap);
        #endif
        char* data = malloc(cap);
        int iserr = 1;
        if(data) {
            pthread_cleanup_push((void*)&free, data);
            while(1) {
                if(fseek(fp, next, SEEK_SET)) {
                    iserr = 1;
                    break;
                }
                if(fread(data, cap, 1, fp) == 1) {
                    if(!ftruncate(fileno(fp), end - spb->real_len)) {
                        if(fseek(fp, this, SEEK_SET)) {
                            iserr = 1;
                            break;
                        }
                        if(fwrite(data, cap, 1, fp) == 1) {
                            iserr = 0;
                            break;
                        }
                    }
                }
                break;
            }
            pthread_cleanup_pop(1);
        }
        if(iserr) goto ERR_INSERT_ITEM;
        break;
    }
    if(fseek(fp, 0, SEEK_END)) goto ERR_INSERT_ITEM;
TRY_INSERT_ITEM:
    if(set_pb(fp, items_len, sizeof(dict_t), dict))
        return 0;
ERR_INSERT_ITEM:
    return 1;
}

static int s3_set_data(thread_timer_t *timer) {
    if(!setdicts[timer->index].data[0]) return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);
    FILE *fp = open_dict(timer->index, 0);
    if(fp == NULL) return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);

    int datasize = (timer->numbytes > (DICTDATSZ-1))?(DICTDATSZ-1):timer->numbytes;
    #ifdef DEBUG
        printf("Set data size: %u\n", datasize);
    #endif
    if(datasize <= 0 || datasize > sizeof(setdicts[timer->index].data)) 
        return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);

    int r;
    pthread_cleanup_push((void*)&close_dict, (void*)(uintptr_t)timer->index);

    uint8_t* dp = (uint8_t*)setdicts[timer->index].data;
    touch_timer(timer);
    int p = ((*((uint32_t*)dp))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ;
    dict_t* setdict;

    if(!dict_pool[p]) {
        setdict = dict_pool[p] = (dict_t*)malloc(sizeof(dict_t));
        memcpy(setdict->key, setdicts[timer->index].key, DICTKEYSZ);
    }
    else {
        int c = 16-4;
        int notok;
        while(dict_pool[p] && (notok=strcmp(setdicts[timer->index].key, dict_pool[p]->key)) && c-->0) {
            #ifdef DEBUG
                printf("digest of %s: %08x got conflicted, remaining chance: %d.\n", setdicts[timer->index].key, p, c);
            #endif
            p = ((*((uint32_t*)(++dp)))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ; // 哈希碰撞
            #ifdef DEBUG
                printf("skip digest of %s to %08x.\n", setdicts[timer->index].key, p);
            #endif
        }
        if(!dict_pool[p]) {
            setdict = dict_pool[p] = (dict_t*)malloc(sizeof(dict_t)); // 无值
            memcpy(setdict->key, setdicts[timer->index].key, DICTKEYSZ);
        }
        else if(notok) setdict = &setdicts[timer->index]; // 全部冲突
        else setdict = dict_pool[p]; // 已有值
    }
    #ifdef DEBUG
        printf("item %s(%0*x) will fill into %p.\n", setdicts[timer->index].key, DICTPOOLBIT/4, p, dict_pool[p]);
    #endif

    memset(setdict->data, 0, DICTDATSZ);
    memcpy(setdict->data, timer->dat, timer->numbytes);

    if(insert_item(fp, setdict, strlen(setdict->key)+1, datasize)) {
        fprintf(stderr, "Error set data: dict[%s]=%s\n", setdict->key, timer->dat);
        r = send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);
    } else {
        printf("Set dict[%s]=%s\n", setdict->key, timer->dat);
        r = send_data(timer->accept_fd, timer->index,  ACKSUCC, "succ", 4);
    }

    setdicts[timer->index].data[0] = 0;

    pthread_cleanup_pop(1);
    return r;
}

static server_ack_t del(FILE *fp, const char* key, int len, char ret[4]) {
    int ch;
    uint8_t buf[8+DICTSZ];
    while(has_next(fp, ch)) {
        if(!ch) continue; // skip null bytes
        SIMPLE_PB* spb = read_pb_into(fp, (SIMPLE_PB*)buf);
        if(!spb)  {
            fputs("Bad spb file", stderr);
            pthread_exit(NULL);
        }
        dict_t* d = (dict_t*)spb->target;
        if(memcmp(key, d->key, len)) continue;
        uint32_t next = ftell(fp);
        uint32_t this = next - spb->real_len;
        if(fseek(fp, 0, SEEK_END)) {
            *(uint32_t*)ret = *(uint32_t*)"erro";
            return ACKERRO;
        }
        uint32_t end = ftell(fp);
        if(next == end) {
            if(!ftruncate(fileno(fp), end - spb->real_len)) {
                *(uint32_t*)ret = *(uint32_t*)"succ";
                return ACKSUCC;
            }
            *(uint32_t*)ret = *(uint32_t*)"erro";
            return ACKERRO;
        }
        uint32_t cap = end - next;
        #ifdef DEBUG
            printf("this: %u, next: %u, end: %u, cap: %u\n", this, next, end, cap);
        #endif
        char* data = malloc(cap);
        server_ack_t ack = 0;
        if(data) {
            pthread_cleanup_push((void*)&free, data);
            while(1) {
                if(fseek(fp, next, SEEK_SET)) {
                    *(uint32_t*)ret = *(uint32_t*)"erro";
                    ack = ACKERRO;
                    break;
                }
                if(fread(data, cap, 1, fp) == 1) {
                    if(!ftruncate(fileno(fp), end - spb->real_len)) {
                        if(fseek(fp, this, SEEK_SET))  {
                            *(uint32_t*)ret = *(uint32_t*)"erro";
                            ack = ACKERRO;
                            break;
                        }
                        if(fwrite(data, cap, 1, fp) == 1) {
                            *(uint32_t*)ret = *(uint32_t*)"succ";
                            ack = ACKSUCC;
                            break;
                        }
                    }
                }
                break;
            }
            pthread_cleanup_pop(1);
        }
        if(ack) return ack;
        *(uint32_t*)ret = *(uint32_t*)"erro";
        return ACKERRO;
    }
    *(uint32_t*)ret = *(uint32_t*)"null";
    return ACKNULL;
}

static int s4_del(thread_timer_t *timer) {
    uint8_t digest[16];
    char ret[4];
    int r;
    FILE *fp = open_dict(timer->index, 0);
    if(fp == NULL) return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);

    pthread_cleanup_push((void*)&close_dict, (void*)(uintptr_t)timer->index);
    while(1) {
        md5((uint8_t*)timer->dat, strlen(timer->dat)+1, digest);
        uint8_t* dp = digest;
        int p = ((*((uint32_t*)digest))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ;
        int c = 16-4;
        int notok = 1;
        while(dict_pool[p] && (notok=strcmp(timer->dat, dict_pool[p]->key)) && c-->0) {
            #ifdef DEBUG
                printf("digest of %s: %08x got conflicted, remaining chance: %d.\n", timer->dat, p, c);
            #endif
            p = ((*((uint32_t*)(++dp)))>>(8*sizeof(uint32_t)-DICTPOOLBIT))&DICTPOOLSZ; // 哈希碰撞
            #ifdef DEBUG
                printf("skip digest of %s to %08x.\n", timer->dat, p);
            #endif
        }
        if(!dict_pool[p] || notok) {
            r = send_data(timer->accept_fd, timer->index, ACKNULL, "null", 4);
            break;
        }
        free(dict_pool[p]);
        dict_pool[p] = NULL;
        r = send_data(timer->accept_fd, timer->index, del(fp, timer->dat, timer->numbytes+1, ret), ret, 4);
        break;
    }
    pthread_cleanup_pop(1);
    return r;
}

static int s5_md5(thread_timer_t *timer) {
    FILE* fp = open_dict(timer->index, 1);
    if(fp == NULL) return send_data(timer->accept_fd, timer->index, ACKERRO, "erro", 4);
    int r;
    pthread_cleanup_push((void*)&close_dict, (void*)(uintptr_t)timer->index);
    fill_md5(fp);
    r = is_dict_md5_equal((uint8_t*)timer->dat);
    pthread_cleanup_pop(1);
    if(r) return send_data(timer->accept_fd, timer->index, ACKNULL, "null", 4);
    else return send_data(timer->accept_fd, timer->index, ACKNEQU, "nequ", 4);
}

static void handle_quit(int signo) {
    puts("Handle sigquit");
    pthread_exit(NULL);
}

static void handle_segv(int signo) {
    puts("Handle kill/segv/term");
    fflush(stdout);
    pthread_exit(NULL);
}

static void accept_timer(void *p) {
    thread_timer_t *timer = timer_pointer_of(p);
    uint32_t index = timer->index;
    pthread_t thread = timer->thread;
    sigset_t mask;

    sigemptyset(&mask);
    sigaddset(&mask, SIGPIPE); // 防止处理嵌套
    pthread_sigmask(SIG_BLOCK, &mask, NULL);

    while(!pthread_kill(thread, 0)) {
        sleep(MAXWAITSEC / 4);
        if(is_dict_opening) touch_timer(p);
        time_t waitsec = time(NULL) - timer->touch;
        printf("Wait sec: %u, max: %u\n", (unsigned int)waitsec, MAXWAITSEC);
        if(waitsec > MAXWAITSEC) {
            pthread_kill(thread, SIGQUIT);
            puts("Kill thread");
            break;
        }
    }
}

static void cleanup_thread(thread_timer_t* timer) {
    sigset_t mask;
    sigemptyset(&mask);
    sigaddset(&mask, SIGPIPE); // 防止处理嵌套
    pthread_sigmask(SIG_BLOCK, &mask, NULL);
    puts("Start cleaning");
    timer->thread = 0;
    setdicts[timer->index].data[0] = 0;
    if(timer->accept_fd) {
        close(timer->accept_fd);
        timer->accept_fd = 0;
        puts("Close accept");
    }
    close_dict(timer->index);
    puts("Finish cleaning");
}

static void handle_int(int signo) {
    puts("Keyboard interrupted");
    pthread_exit(NULL);
}

static void handle_pipe(int signo) {
    puts("Pipe error, exit thread...");
    pthread_exit(NULL);
}

static void handle_accept(void *p) {
    puts("Handling accept...");
    pthread_t thread;
    if (pthread_create(&thread, &attr, (void *)&accept_timer, p)) {
        perror("Error creating timer thread");
        cleanup_thread(timer_pointer_of(p));
        return;
    }
    puts("Creating timer thread succeeded");
    pthread_cleanup_push((void*)&cleanup_thread, p);
    int accept_fd = timer_pointer_of(p)->accept_fd;
    uint32_t index = timer_pointer_of(p)->index;
    uint8_t *buff = timer_pointer_of(p)->buf;
    cmdpacket_t cp = (cmdpacket_t)buff;
    ssize_t numbytes = 0, offset = 0;
    while(
            offset >= CMDPACKET_HEAD_LEN
            || (numbytes = recv(accept_fd, buff+offset, CMDPACKET_HEAD_LEN-offset, MSG_WAITALL)) > 0
        ) {
        touch_timer(p);
        offset += numbytes;
        #ifdef DEBUG
            printf("[handle] Get %zd bytes, total: %zd.\n", numbytes, offset);
        #endif
        if(offset < CMDPACKET_HEAD_LEN) break;
        if(offset < CMDPACKET_HEAD_LEN+(ssize_t)(cp->datalen)) {
            ssize_t toread = CMDPACKET_HEAD_LEN+(ssize_t)(cp->datalen)-offset;
            numbytes = recv(accept_fd, buff+offset, toread, MSG_WAITALL);
            if(numbytes != toread) break;
            else {
                offset += numbytes;
                #ifdef DEBUG
                    printf("[handle] Get %zd bytes, total: %zd.\n", numbytes, offset);
                #endif
            }
        }
        numbytes = CMDPACKET_HEAD_LEN+(ssize_t)(cp->datalen); // 暂存 packet len
        if(offset < numbytes) break;
        #ifdef DEBUG
            printf("[handle] Decrypt %d bytes data...\n", (int)cp->datalen);
        #endif
        if(cp->cmd <= CMDEND) {
            if(cmdpacket_decrypt(cp, index, cfg.pwd)) {
                cp->data[cp->datalen] = 0;
                timer_pointer_of(p)->dat = (char*)cp->data;
                timer_pointer_of(p)->numbytes = (ssize_t)(cp->datalen);
                printf("[normal] Get %zd bytes packet with cmd: %d, data: %s\n", offset, cp->cmd, cp->data);
                switch(cp->cmd) {
                    case CMDGET:
                        if(!has_dict_opened && !s1_get(timer_pointer_of(p))) goto CONV_END;
                    break;
                    case CMDCAT:
                        if(!has_dict_opened && !send_all(timer_pointer_of(p))) goto CONV_END;
                    break;
                    case CMDMD5:
                        if(!has_dict_opened && !s5_md5(timer_pointer_of(p))) goto CONV_END;
                    break;
                    case CMDACK:
                    case CMDEND:
                    default: goto CONV_END; break;
                }
            } else {
                puts("Decrypt normal data failed");
                break;
            }
        } else if(cp->cmd <= CMDDAT) {
            if(cmdpacket_decrypt(cp, index, cfg.sps)) {
                cp->data[cp->datalen] = 0;
                timer_pointer_of(p)->dat = (char*)cp->data;
                timer_pointer_of(p)->numbytes = (ssize_t)(cp->datalen);
                printf("[super] Get %zd bytes packet with data: %s\n", offset, cp->data);
                switch(cp->cmd) {
                    case CMDSET:
                        if(!has_dict_opened && !s2_set(timer_pointer_of(p))) goto CONV_END;
                    break;
                    case CMDDEL:
                        if(!has_dict_opened && !s4_del(timer_pointer_of(p))) goto CONV_END;
                    break;
                    case CMDDAT:
                        if(!has_dict_opened && !s3_set_data(timer_pointer_of(p))) goto CONV_END;
                    break;
                    default: goto CONV_END; break;
                }
            } else {
                puts("Decrypt super data failed");
                break;
            }
        } else {
            puts("Invalid command");
            break;
        }
        if(offset > numbytes) {
            offset -= numbytes;
            memmove(buff, buff+numbytes, offset);
            numbytes = 0;
        } else offset = 0;
        #ifdef DEBUG
            printf("Offset after analyzing packet: %zd\n", offset);
        #endif
    }
    CONV_END: puts("Conversation end");
    pthread_cleanup_pop(1);
    puts("Thread exited normally");
}

static void accept_client(int fd) {
    /*pid_t pid = fork();
    while (pid > 0) {      // 主进程监控子进程状态，如果子进程异常终止则重启之
        wait(NULL);
        puts("Server subprocess exited. Restart...");
        pid = fork();
    }
    while(pid < 0) {
        perror("Error when forking a subprocess");
        sleep(1);
    }*/
    signal(SIGINT,  handle_int);
    signal(SIGQUIT, handle_quit);
    signal(SIGKILL, handle_segv);
    signal(SIGSEGV, handle_segv);
    signal(SIGPIPE, handle_pipe);
    signal(SIGTERM, handle_segv);
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
    init_crypto();
    init_dict_pool(open_dict(0, 1));
    close_dict(0);
    while(1) {
        puts("Ready for accept, waitting...");
        int p = 0;
        while(p < THREADCNT && timers[p].thread) p++;
        if(p >= THREADCNT) {
            puts("Max thread cnt exceeded");
            sleep(1);
            continue;
        }
        #ifdef LISTEN_ON_IPV6
            struct sockaddr_in6 client_addr;
        #else
            struct sockaddr_in client_addr;
        #endif
        int accept_fd;
        while((accept_fd=accept(fd, (struct sockaddr *)&client_addr, &struct_len))<=0)
            perror("Accept client error");
        #ifdef LISTEN_ON_IPV6
            uint16_t port = ntohs(client_addr.sin6_port);
            struct in6_addr in = client_addr.sin6_addr;
            char str[INET6_ADDRSTRLEN];	// 46
            inet_ntop(AF_INET6, &in, str, sizeof(str));
        #else
            uint16_t port = ntohs(client_addr.sin_port);
            struct in_addr in = client_addr.sin_addr;
            char str[INET_ADDRSTRLEN];	// 16
            inet_ntop(AF_INET, &in, str, sizeof(str));
        #endif
        time_t t = time(NULL);
        printf("\n> %sAccept client %s:%u at slot No.%d\n", ctime(&t), str, port, p);
        thread_timer_t* timer = &timers[p];
        timer->accept_fd = accept_fd;
        timer->index = p;
        timer->touch = time(NULL);
        reset_seq(p);
        if (pthread_create(&timer->thread, &attr, (void *)&handle_accept, timer)) {
            perror("Error creating thread");
            cleanup_thread(timer);
            continue;
        }
        puts("Creating thread succeeded");
    }
}

#define argequ(i, arg) (*(uint16_t*)argv[i] == *(uint16_t*)(arg))
#define showUsage(program) \
    printf("Usage:\n%s [-d] listen_port dict_file [ config_file | - ]\n\t-d: As daemon\n\t- : Read config from env SDS_PWD & SDS_SPS\n", program)
int main(int argc, char *argv[]) {
    if(argc != 4 && argc != 5) {
        showUsage(argv[0]);
        return 0;
    }
    int port = 0;
    int as_daemon = argequ(1, "-d");
    sscanf(argv[as_daemon?2:1], "%d", &port);
    if(port < 0 || port >= 65536) {
        fprintf(stderr, "Error port: %d\n", port);
        return 1;
    }
    if(as_daemon && daemon(1, 1)<0) {
        perror("Start daemon error");
        return 2;
    }
    FILE *fp = NULL;
    fp = fopen(argv[as_daemon?3:2], "rb+");
    if(!fp) fp = fopen(argv[as_daemon?3:2], "wb+");
    if(!fp) {
        fprintf(stderr, "Error opening dict file: %s", argv[as_daemon?3:2]);
        perror("");
        return 3;
    }
    fclose(fp);
    if(init_dict(argv[as_daemon?3:2]))
        return 4;
    fp = NULL;
    if(argv[as_daemon?4:3][0] == '-') { // use env
        fp = (FILE*)1;
        puts("Read config from env");
        char* pwd = getenv("SDS_PWD");
        if(pwd) {
            char* sps = getenv("SDS_SPS");
            if(sps) {
                strncpy(cfg.pwd, pwd, 64);
                strncpy(cfg.sps, sps, 64);
                cfg.pwd[63] = 0;
                cfg.sps[63] = 0;
                fp = (FILE*)-1;
            } else {
                fputs("Env SDS_SPS is null", stderr);
                return 5;
            }
        } else {
            fputs("Env SDS_PWD is null", stderr);
            return 6;
        }
    }
    if(!fp) fp = fopen(argv[as_daemon?4:3], "rb");
    if(fp == NULL) {
        fprintf(stderr, "Error opening config file: %s", argv[as_daemon?4:3]);
        perror("fopen");
        return 7;
    }
    if(~((int)fp)) {
        uint8_t buf[8+sizeof(CONFIG)];
        SIMPLE_PB* spb = read_pb_into(fp, (SIMPLE_PB*)buf);
        if(!spb) {
            fprintf(stderr, "Error reading config file: %s\n", argv[as_daemon?4:3]);
            return 8;
        }
        cfg = *(CONFIG*)(spb->target);
        fclose(fp);
    }
    items_len = align_struct(sizeof(dict_t), 2, setdicts[0].key, setdicts[0].data);
    if(!items_len) {
        fputs("Align struct error", stderr);
        return 9;
    }
    int fd;
    if(!(fd=bind_server((uint16_t*)&port))) return 10;
    if(!listen_socket(fd)) return 11;
    pthread_cleanup_push((void*)&close, (void*)((long long)fd));
    accept_client(fd);
    pthread_cleanup_pop(1);
    return 0;
}