archive.c

Linux系统备份源代码 可基于用户自定义策略实现系统、应用数据备份

                               ,currtime->tm_year+1900
                               ,currtime->tm_hour
                               ,currtime->tm_min);
    debug("generated archiveid is \"%s\"\n",conf__archive_oldid);
  }


  /*try to write the archive id to file*/
  if(__write_archiveid())
    return -1;


  /*no problems*/
  return 0;
}



/********************************************************************
  int OldArchiveId()

  Try to obtain the archive id if the device or archive is
  already present.

  arguments:
    none
  return:
    -1 on error
    0 on success
*****************************************************************/
int OldArchiveId()
{
  FILE *file;
  int pid=-1;
  char strn[1024];
  int status;
  unsigned type=0;
  struct stat fi;
  int initial_err_size=0;
  char command[256];
  int rc;
  int first_try=0;
  struct stat statbuf;
  char archiveid_file[4096];


  /* Types of archive that is handled in other ways */
  if(conf__type==FILECOPY)
  {
    /* Does the archive exists ?? */
    debug("Looking for an archive id in a filecopy archive\n");
    if(stat(conf__archive,&statbuf))
    {
      debug("Archive does not exist, no archive id\n");
      return 0;
    }


    /* We have the archive id file, get the id */
    snprintf(archiveid_file,4096,"%s/sitback.archiveid",conf__archive);
    if((file=fopen(archiveid_file,"r"))==NULL)
    {
      debug("No archive id file \n");
      return 0;
    }
    fgets(strn,256,file);
    fclose(file);
    if(strn[strlen(strn)-1]=='\n')
      strn[strlen(strn)-1]='\0';
    debug("Read the archiveid '%s'\n",strn);
    strcpy(conf__archive_id,strn);
    return 0;
  }


  /* Try to get the old archiveid assuming different types of tar archive */
  debug("Trying to find an old archive id\n");
  for(;;)
  {
    /*wait for the device to become available*/
    if(ArchiveReady(3600))
    {
      errcode=50;
      log("Archive or device no longer available");
      return -1;
    }

    /*remove the sitback.archiveid file so that we may detect any new
      file extracted from the archive*/
    if(unlink("sitback.tmpout") && errno!=ENOENT)
    {
      errcode=24;
      UI__Warning("Unable to delete 'sitback.tmperr'. %d '%s'",errno,strerror(errno));
      return -1;
    }

    /* remove any previous sitback.tmperr, so that we
      can detect any errors */
    if(unlink("sitback.tmperr") && errno!=ENOENT)
    {
      errcode=24;
      UI__Warning("Unable to delete 'sitback.tmperr'. %d '%s'",errno,strerror(errno));
      return -1;
    }


    /* try extracting the id from non-compressed or compressed archives */
    debug("Trying archive type %u\n",type);
    switch(type)
    {
      case 0:
      {
        if(conf__compressapp!=NULL && strstr(conf__compressapp,"bzip2")!=NULL)
        {
          /* search for an archiveid assuming the archive is compressed with bzip2 */
          if(conf__bzip2[0]!='\0')
          {
            debug("Assuming bzip2 compressed archive\n");
            if(conf__rhost[0]=='\0')
              sprintf(command,"tar -x --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__bzip2,conf__archive);
            else
              sprintf(command,"tar -x --rsh-command=%s --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__rsh,conf__bzip2,conf__archive);
          }
          first_try=2;
        }
        else if(conf__compressapp!=NULL && strstr(conf__compressapp,"gzip")!=NULL)
        {
          /* search for an archiveid assuming the archive is compressed with gzip */
          if(conf__gzip[0]!='\0')
          {
            debug("Assuming gzip compressed archive\n");
            if(conf__rhost[0]=='\0')
              sprintf(command,"tar -x --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__gzip,conf__archive);
            else
              sprintf(command,"tar -x --rsh-command=%s --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__rsh,conf__gzip,conf__archive);
          }
          first_try=3;
        }
        else if(conf__compressapp!=NULL && strstr(conf__compressapp,"compress")!=NULL)
        {
          /* search for an archiveid assuming the archive is compressed with gzip */
          if(conf__gzip[0]!='\0')
          {
            debug("Assuming compress compressed archive\n");
            if(conf__rhost[0]=='\0')
              sprintf(command,"tar -x --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__gzip,conf__archive);
            else
              sprintf(command,"tar -x --rsh-command=%s --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__rsh,conf__gzip,conf__archive);
          }
          first_try=4;
        }
        else
        {
          /*Search for an archiveid assuming the archive is uncompressed*/
          debug("Assuming non-compressed archive\n");
          if(conf__rhost[0]=='\0')
            sprintf(command,"tar -x -P -O -f %s sitback.archiveid",conf__archive);
          else
            sprintf(command,"tar -x --rsh-command=%s -P -O -f %s sitback.archiveid",conf__rsh,conf__archive);
          first_try=1;
        }
        if((pid=Execute(command))==-1)
          return -1;
        debug("Now searching\n");
        type++;
        break;
      }
      case 1:
      {
        /*Search for an archiveid assuming the archive is uncompressed*/
        if(first_try!=1)
        {
          debug("Assuming non-compressed archive\n");
          if(conf__rhost[0]=='\0')
            sprintf(command,"tar -x -P -O -f %s sitback.archiveid",conf__archive);
          else
            sprintf(command,"tar -x --rsh-command=%s -P -O -f %s sitback.archiveid",conf__rsh,conf__archive);
          if((pid=Execute(command))==-1)
            return -1;
          debug("Now searching\n");
        }
        type++;
        break;
      }
      case 2:
      {
        /* search for an archiveid assuming the archive is compressed with bzip2 */
        if(conf__bzip2[0]!='\0' && first_try!=2)
        {
          debug("Assuming bzip2 compressed archive\n");
          if(conf__rhost[0]=='\0')
            sprintf(command,"tar -x --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__bzip2,conf__archive);
          else
            sprintf(command,"tar -x --rsh-command=%s --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__rsh,conf__bzip2,conf__archive);
          if((pid=Execute(command))==-1)
            return -1;
          debug("Now searching\n");
        }
        type++;
        break;
      }
      case 3:
      {
        /* search for an archiveid assuming the archive is compressed with gzip */
        if(conf__gzip[0]!='\0' && first_try!=3)
        {
          debug("Assuming gzip compressed archive\n");
          if(conf__rhost[0]=='\0')
            sprintf(command,"tar -x --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__gzip,conf__archive);
          else
            sprintf(command,"tar -x --rsh-command=%s --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__rsh,conf__gzip,conf__archive);
          if((pid=Execute(command))==-1)
            return -1;
          debug("Now searching\n");
        }
        type++;
          break;
      }
      case 4:
      {
        /* search for an archiveid assuming the archive is compressed with compress */
        if(conf__Zcompress[0]!='\0' && first_try!=4)
        {
          debug("Assuming compress compressed archive\n");
          if(conf__rhost[0]=='\0')
            sprintf(command,"tar -x --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__Zcompress,conf__archive);
          else
            sprintf(command,"tar -x --rsh-command=%s --use-compress-program %s -P -O -f %s sitback.archiveid ",conf__rsh,conf__Zcompress,conf__archive);
          if((pid=Execute(command))==-1)
            return -1;
          debug("Now searching\n");
        }
        type++;
        break;
      }
      default:
      {
        /*no problems, but no id*/
        debug("No more types of archives..  stopping\n");
        log("No archive id");
          return 0;
      }
    }

    /* Wait until we either got an archiveid or tar has stopped running */
    while(1)
    {
      /*dont overpower the cpu*/
      sleep(1);

      /* any errors ?? */
      if(!stat("sitback.tmperr",&fi))
      {
        if(initial_err_size==0)
          initial_err_size=fi.st_size;
        else if(fi.st_size!=initial_err_size)
        {
          /* errors..  kill tar */
          debug("Errors while searching for the archive id\n");
          Kill(pid);
          break;
        }
      }


      /*check if we got the archiveid*/
      if((file=fopen("sitback.tmpout","r"))!=NULL)
      {
        if(fgets(strn,300,file)!=NULL)
        {
          debug("got archiveid, aborting the search\n");
          fclose(file);
          Kill(pid);
          break;
        }
        fclose(file);
      }


      /*make sure tar is still alive*/
      if(waitpid(pid,&status,WNOHANG | WUNTRACED)!=0)
      {
        debug("process no longer running, continuing checking for archiveid\n");
        break;
      }
    }


    /*make sure we dont have a zombie tar*/
    while((rc=waitpid(-1,&status,WNOHANG))>0);


    /*did we get a valid archive-id*/
    if((file=fopen("sitback.tmpout","r"))!=NULL)
    {
      /*read no more than 256 characters*/
      fgets(conf__archive_oldid,256,file);
      fclose(file);
      if(conf__archive_oldid[strlen(conf__archive_oldid)-1]=='\n')
        conf__archive_oldid[strlen(conf__archive_oldid)-1]='\0';


      /*is it a valid archiveid*/
      if(conf__archive_oldid[0]!='\n' && conf__archive_oldid[0]!='\0')
      {
        debug("got valid archiveid \"%s\"\n",conf__archive_oldid);


        /*do not continue*/
        sprintf(strn,"Id: '%s'\n",conf__archive_oldid);
        UI__Message(strn);
        log("Found archive id '%s'",conf__archive_oldid);
        return 0;
      }
    }


    /*wait until the device is ready*/
    if(ArchiveReady(3600))
    {
      errcode=50;
      log("Archive or device no longer available");
      return -1;
    }


    /* rewind */
    if(RewindDevice())
      return -1;
  }


  /*no problems, but no id*/
  log("No archive id");
  return 0;
}



/********************************************************************
  int __write_archiveid()

  Write the sitback.archiveid file

  arguments:
    none
  return:
    -1 on error
    0 on success
********************************************************************/
int __write_archiveid()
{
  FILE *file;


  /*try to open the file*/
  if((file=fopen("sitback.archiveid","w"))==NULL)
  {
    UI__Warning("Unable to write the archiveid to file\n");
    errcode=30;
    log("Unable to write the archiveid to file");
    return -1;
  }


  /*write the archiveid to the file*/
  if(conf__archive_id[0]!='\0')
  {
    debug("force archiveid \"%s\"\n",conf__archive_id);
    fprintf(file,"%s",conf__archive_id);


    /*rename the entry*/
    if(conf__archive_oldid[0]!='\0')
    {
      /*try to rename the entry, then set the status..
        Rename may fail if the database directory does not
        exist, perhaps due to a new-installation after a
        crach, so ignore the error*/
      if(DataBaseRename(conf__archive_oldid,conf__archive_id)!=-1)
        DataBaseSetStatus(conf__archive_id,"UNKNOWN");
    }
  }
  else
  {
    strcpy(conf__archive_id,conf__archive_oldid);
    fprintf(file,"%s\n",conf__archive_id);
  }
  fclose(file);


  /*no problems*/
  return 0;
}