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# File.php

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    00001 <?PHP
    00002
    00003 #
    00004 #   FILE:  File.php
    00005 #
    00006 #   Copyright 2010 Edward Almasy and Internet Scout
    00007 #   http://scout.wisc.edu
    00008 #
    00009
    00010
    00011 class File {
    00012
    00013     # ---- PUBLIC INTERFACE --------------------------------------------------
    00014
    00015     # status codes (set by constructor and returned by File::Status())
    00016     const FILESTAT_OK =             0;
    00017     const FILESTAT_COPYERROR =      1;
    00018     const FILESTAT_PARAMERROR =     2;
    00019     const FILESTAT_ZEROLENGTH =     3;
    00020     const FILESTAT_DOESNOTEXIST =   4;
    00021     const FILESTAT_UNREADABLE =     5;
    00022
    00023     # object constructor
    00024     function File($IdOrFileName, $ResourceId = NULL, $FieldId = NULL,
    00025             $DesiredFileName = NULL, $CheckFileLength = TRUE)
    00026     {
    00027         # assume constructor will succeed
    00028         $this->Status = self::FILESTAT_OK;
    00029
    00030         # get our own database handle
    00031         $DB = new Database();
    00032         $this->DB = $DB;
    00033
    00034         # if ID supplied
    00035         if (is_int($IdOrFileName))
    00036         {
    00037             # set file ID from supplied value
    00038             $this->Id = intval($IdOrFileName);
    00039
    00040             # load file info from database
    00041             $DB->Query("SELECT * FROM Files WHERE FileId = ".$this->Id);
    00042             $this->DBFields = $DB->FetchRow();
    00043         }
    00044         # else if file name and resource ID and field ID supplied
    00045         elseif (strlen($IdOrFileName) && ($ResourceId != NULL) && ($FieldId != NULL))
    00046         {
    00047             # if file does not exist
    00048             $TempFileName = $IdOrFileName;
    00049             if (!file_exists($TempFileName) || !is_readable($TempFileName))
    00050             {
    00051                 # set status indicating appropriate error
    00052                 $this->Status = file_exists($TempFileName)
    00053                         ? self::FILESTAT_DOESNOTEXIST : self::FILESTAT_UNREADABLE;
    00054             }
    00055             else
    00056             {
    00057                 # if we were asked to check file length and file was zero length
    00058                 $FileLength = filesize($TempFileName);
    00059                 if ($CheckFileLength && !$FileLength)
    00060                 {
    00061                     # set status indicating zero length file
    00062                     $this->Status = self::FILESTAT_ZEROLENGTH;
    00063                 }
    00064                 else
    00065                 {
    00066                     # generate secret string (used to protect from unauthorized download)
    00067                     srand((double)microtime() * 1000000);
    00068                     $SecretString = sprintf("%04X", rand(1, 30000));
    00069
    00070                     # attempt to get file type
    00071                     if (function_exists("finfo_open"))
    00072                     {
    00073                         $FInfoHandle = finfo_open(FILEINFO_MIME);
    00074                         $FileType = finfo_file($FInfoHandle, $TempFileName);
    00075                         finfo_close($FInfoHandle);
    00076                     }
    00077                     else
    00078                     {
    00079                         $FileType = "";
    00080                     }
    00081
    00082                     # add file info to database
    00083                     $BaseFileName = $DesiredFileName
    00084                             ? basename($DesiredFileName) : basename($TempFileName);
    00085                     $DB->Query("INSERT INTO Files"
    00086                             ." (ResourceId, FieldId, FileName, FileLength, FileType,"
    00087                                 ." SecretString)"
    00088                             ." VALUES ("
    00089                                 .intval($ResourceId).", "
    00090                                 .intval($FieldId).", "
    00091                                 ."'".addslashes($BaseFileName)."', "
    00092                                 .$FileLength.", "
    00093                                 ."'".$FileType."', "
    00094                                 ."'".$SecretString."')");
    00095
    00096                     # retrieve ID of new file
    00097                     $this->Id = $DB->LastInsertId("Files");
    00098
    00099                     # load file info back in from database
    00100                     $DB->Query("SELECT * FROM Files WHERE FileId = ".$this->Id);
    00101                     $this->DBFields = $DB->FetchRow();
    00102
    00103                     # copy file to storage
    00104                     $CopySucceeded = copy($IdOrFileName, $this->GetNameOfStoredFile());
    00105
    00106                     # if copy failed
    00107                     if (!$CopySucceeded)
    00108                     {
    00109                         # remove file info from database
    00110                         $DB->Query("DELETE FROM Files WHERE FileId = ".$this->Id);
    00111
    00112                         # set status indicating constructor failed
    00113                         $this->Status = self::FILESTAT_COPYERROR;
    00114                     }
    00115                 }
    00116             }
    00117         }
    00118         else
    00119         {
    00120             # set status indicating constructor failed
    00121             $this->Status = self::FILESTAT_PARAMERROR;
    00122         }
    00123     }
    00124
    00125     # return object status (used to report errors occurring in constructor)
    00126     function Status() {  return $this->Status;  }
    00127
    00128     # get various attributes
    00129     function Id() {  return $this->Id;  }
    00130     function Name() {  return $this->DBFields["FileName"];  }
    00131     function GetLength() {  return $this->DBFields["FileLength"];  }
    00132     function GetType() {  return $this->DBFields["FileType"];  }
    00133
    00134     # get/set various attributes
    00135     function Comment($NewValue = DB_NOVALUE)
    00136             {  return $this->UpdateValue("FileComment", $NewValue);  }
    00137     function FieldId($NewValue = DB_NOVALUE)
    00138             {  return $this->UpdateValue("FieldId", $NewValue);  }
    00139     function ResourceId($NewValue = DB_NOVALUE)
    00140             {  return $this->UpdateValue("ResourceId", $NewValue);  }
    00141
    00142     # get MIME type (defaults to "application/octet-stream" if not available)
    00143     function GetMimeType()
    00144     {
    00145         return strlen($this->GetType())
    00146                 ? $this->GetType() : "application/octet-stream";
    00147     }
    00148
    00149     # get link for downloading file
    00150     function GetLink()
    00151     {
    00152         return "index.php?P=DownloadFile&Id=".$this->Id;
    00153     }
    00154
    00155     # delete file (other methods are invalid after calling this!)
    00156     function Delete()
    00157     {
    00158         # remove file entry from DB
    00159         $this->DB->Query("DELETE FROM Files WHERE FileId = ".$this->Id);
    00160
    00161         # delete file
    00162         $FileName = $this->GetNameOfStoredFile();
    00163         if (file_exists($FileName))
    00164         {
    00165             unlink($FileName);
    00166         }
    00167     }
    00168
    00169     # retrieve actual name of stored file
    00170     function GetNameOfStoredFile()
    00171     {
    00172         return sprintf("FileStorage/%06d-%s-%s",
    00173                 $this->Id, $this->DBFields["SecretString"], $this->Name());
    00174     }
    00175
    00176
    00177     # ---- PRIVATE INTERFACE -------------------------------------------------
    00178
    00179     private $DB;
    00180     private $Status;
    00181     private $Id;
    00182     private $DBFields;
    00183
    00184     # convenience function to supply parameters to Database->UpdateValue()
    00185     private function UpdateValue($FieldName, $NewValue)
    00186     {
    00187         return $this->DB->UpdateValue("Files", $FieldName, $NewValue,
    00188                                "FileId = ".intval($this->Id),
    00189                                $this->DBFields, TRUE);
    00190     }
    00191 }
    00192
    00193
    00194 ?>