linux下c实现的数据库备份（第四版）

该版本算是比较成熟的啦，欢迎大伙拿来试用！！！

1.新增数据库连接和备份时间配置文件conf

2.新增日志文件，程序运行的一些异常会记录在log文件下

后续的工作：

1.将代码切割为多个文件，分类存放代码

2.加入自动后台运行的支持

3.加入开机自动运行的支持

完成上面3个之后，我的linux c数据库备份程序就暂时靠一段落了。

使用提醒：

编译：gcc -o main main.c

后台启动：./main &

停止程序：./main stop

#include<sys/types.h> #include<sys/wait.h> #include<ctype.h> #include<unistd.h> #include<string.h> #include<stdlib.h> #include<signal.h> #include<time.h> #include<stdio.h> //程序运行的pid信息 #define PID_FILE "./pid.db" //记录待备份的数据库信息文件 #define DB_FILE "./db_list" //配置文件信息 #define CONF_FILE "./conf" //日志文件 #define LOG_FILE "./log" //最大备份的数据库数量 #define NUM 20 //数据库名字长度的限制 #define LEN 128 //程序轮询时间间隔 #define ALARM_TIME 10 //从文件读取到的数据库信息保存至该数组中 char *db_list[NUM]; //当前待备份的数据库数量 int read_num; //是否用户终止备份 int isbreak = 0; //数据库连接信息 typedef struct db_conf {  char *host;  char *user;  char *pass; }CONF; //数据库备份时间 typedef struct bat_t {  int hour;  int min; }BAT_T; //malloc void malloc_dblist(); //free void free_dblist(); //读取待备份的数据库信息 int readDbFile(); //读取配置文件信息（数据库连接信息，备份时间等） CONF readConfFile(); //读取备份的时间信息 BAT_T readBatTFile(); //记录日志信息 void recordLog(char *); //信号处理函数 void signHandler(int sig); //记录程序运行的pid信息 int recordPid(int pid); //获取程序运行时的pid信息 int readPid(void); //移除程序运行时的pid信息 void delPid(void); int main(int argc, char *argv[])  {  CONF conf;  BAT_T bt;  pid_t pid, old_pid;  int i, prs;  char buf[LEN];  time_t t;  struct tm *tm_ptr;  struct sigaction act, oldact;  sigset_t newmask, suspmask, oldmask;  if (argc >= 2) {   old_pid = (pid_t)readPid();   //停止掉备份程序   if (strcmp(argv[1], "stop") == 0) {    kill(old_pid, SIGINT);    return 0;   }   else if (strcmp(argv[1], "restart") == 0) {    kill(old_pid, SIGINT);    sleep(5);   }  }  old_pid = (pid_t)readPid();  //检测程序是否已经在运行  if (old_pid > 0) {   fprintf(stderr, "Progress is running./n");   return -1;  }  //记录程序运行的pid信息  prs = recordPid((int)getpid());  if (prs == -1) {   fprintf(stderr, "Open pid.db file error./n");   return -1;  }  //读取待备份的数据库  int rs = readDbFile();  if (rs) {   delPid();   return rs;  }  //读取数据配置信息  conf = readConfFile();  //读取备份时间  bt = readBatTFile();  //信号接管  act.sa_handler = signHandler;  sigemptyset(&act.sa_mask);  act.sa_flags = 0;  sigaction(SIGALRM, &act, 0);  sigaction(SIGINT, &act, 0);  while (1) {   time(&t);   tm_ptr = localtime(&t);   //备份时间内进行备份   if (bt.hour == (int)tm_ptr->tm_hour && bt.min == (int)tm_ptr->tm_min) {    for (i = 0; i < read_num; i++) {     memset(buf, '/0', LEN);     //密码为空     if (!strlen(conf.pass)) {      sprintf(buf, "mysqldump -h%s -u%s %s > %s_%02d%02d%02d.sql",        conf.host, conf.user, db_list[i], db_list[i],        tm_ptr->tm_year+1900, tm_ptr->tm_mon+1, tm_ptr->tm_mday);     }     else {      sprintf(buf, "mysqldump -h%s -u%s -p%s %s > %s_%02d%02d%02d.sql",        conf.host, conf.user, conf.pass, db_list[i], db_list[i],        tm_ptr->tm_year+1900, tm_ptr->tm_mon+1, tm_ptr->tm_mday);     }     system(buf);    }   }   alarm(ALARM_TIME);   pause();   if (isbreak) {    recordLog("User break progress.");    break;   }  }  free_dblist();  delPid();  exit(0); } void malloc_dblist() {  int i = 0;  //malloc for db_list  for (i = 0; i < NUM; i++) {   db_list[i] = malloc(LEN);   memset(db_list[i], '/0', LEN);  } } void free_dblist() {  int i;  //free db_list's memory  for (i = 0; i < NUM; i++) {   free(db_list[i]);  } } int readDbFile() {  FILE *fp;  fp = fopen(DB_FILE, "r");  if (!fp) {   char buf[128];   sprintf(buf, "%s not found/n", DB_FILE);   recordLog(buf);   fprintf(stderr, "%s not found/n", DB_FILE);   return 1;  }  else {   malloc_dblist();   read_num = 0;   while (fscanf(fp, "%127[^/r/n]/n", db_list[read_num]) == 1) {    read_num++;   }   fclose(fp);    return 0;  } } CONF readConfFile() {  FILE *fp;  CONF conf;  if (!(fp = fopen(CONF_FILE, "r"))) {   conf.host = "localhost";   conf.user = "root";   conf.pass = "";   return conf;  }  char buf[128];  while ((fscanf(fp, "%127[^/r/n]/n", buf)) == 1) {   char *tmp1 = strtok(buf, "=");   char *tmp2 = strtok(NULL, "=");   if (strstr(tmp1, "HOST")) {    if (tmp2) {     conf.host = strdup(tmp2);    }    else {     conf.host = "localhost";    }   }   else if (strstr(tmp1, "USER")) {    if (tmp2) {     conf.user = strdup(tmp2);    }    else {     conf.host = "root";    }   }   else if (strstr(tmp1, "PASS")) {    if (tmp2) {     conf.pass = strdup(tmp2);    }    else {     conf.pass = "";    }   }  }  return conf; } BAT_T readBatTFile() {  FILE *fp;  BAT_T bat_time;  if (!(fp = fopen(CONF_FILE, "r"))) {   bat_time.hour = 02;   bat_time.min = 00;   return bat_time;  }  char buf[128];  while ((fscanf(fp, "%127[^/r/n]/n", buf)) == 1) {   if (!strstr(buf, "BAT_TIME"))    continue;   //获取到备份数据数据   char *tmp1 = strtok(buf, "=");   char *tmp2 = strtok(NULL, "=");   //对备份时间数据进行分割   char *hour = strtok(tmp2, " ");   char *min = strtok(NULL, " ");   if (hour) {    bat_time.hour = atoi(hour);   }   else {    bat_time.hour = 02;   }   if (min) {    bat_time.min = atoi(min);   }   else {    bat_time.min = 02;   }  }  return bat_time; } void recordLog(char *msg) {  FILE *fp;  fp = fopen(LOG_FILE, "a");  if (fp) {   time_t t;   struct tm *tm_ptr;   time(&t);   tm_ptr = localtime(&t);   fprintf(fp, "%d-%d-%d %d:%d:%d: %s/n", (tm_ptr->tm_year+1900), tm_ptr->tm_mon, tm_ptr->tm_mday,    tm_ptr->tm_hour, tm_ptr->tm_min, tm_ptr->tm_sec, msg);   fclose(fp);  } } void signHandler(int sig) {  char buf[128];  switch (sig) {   case SIGALRM:    //fprintf(stdout, "alarm signal comming:%d./n", sig);    break;   case SIGINT:    //fprintf(stdout, "sigint signal comming:%d./n", sig);    isbreak = 1;    break;   default:    //fprintf(stdout, "uncatched signal comming:%d./n", sig);    sprintf(buf, "uncatched signal comming:%d./n", sig);    recordLog(buf);  } } int recordPid(int pid) {  FILE *fp = NULL;  if (!(fp = fopen(PID_FILE, "w")))   return -1;  pid = getpid();  fprintf(fp, "%d", (int)pid);  fclose(fp);  return 0; } int readPid(void) {  FILE *fp = NULL;  if (!(fp = fopen(PID_FILE, "r")))   return -1;  int pid;  if (fscanf(fp, "%d", &pid) != 1) {   fclose(fp);   return -2;  }  fclose(fp);  return pid; } void delPid(void) {  unlink(PID_FILE); }