JP2008146514A - Information processor, control method of information processor, and control program of information processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To certainly perform erasing processing for all data which a file occupies on external storage device. <P>SOLUTION: When a file stored in an HDD 8 goes out of use, the information processor memorizes in an erasing management information storage part 91 erasing management information showing the domain which the file occupies on a printing data storage part 81, while performing deletion processing which deletes management information of a file management storage part 82 (S108). After that, when the information processor overwrites on the domain which the file occupies at the printing data storage part 81 to store another file in the HDD 8, the processor performs processing which excludes the domain from the erasing management information of the erasing management information storage part 91 (S112 and S113); and when an opportunity to perform erasing processing comes, the processor performs erasing processing which erases the domain on the printing data storage part 81 corresponding to erasing management information of the erasing management information part 91 using prescribed meaningless data (S114-). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention has a non-volatile storage device that stores input data as a file, and the file data is stored in a data storage unit of the non-volatile storage device and via management information of a file management storage unit of the non-volatile storage device. Information processing apparatus that performs an erasure process for erasing an area occupied by the file on the data storage unit after the file stored in the nonvolatile storage device becomes unnecessary, and a control method for the information processing apparatus And a control program of the information processing apparatus.

  Due to recent advances in computer technology, the increase in capacity and price of hard disks has been remarkable, and as a result, hard disks are often used as low-cost and large-capacity non-volatile storage devices (external storage devices) for general consumer devices. It has become. One example is a printer, and various advantages can be obtained by storing print jobs on a hard disk.

  For example, when the device can store the printed matter without going through the printer server during the printing process, the host computer that issued the print instruction is quickly released. Also, there is an advantage that only one part of data needs to be transmitted when printing a plurality of copies of the same printed matter.

  Further, while the above advantages can be obtained, there is a problem caused by installing a hard disk in the printer. For example, data stored on a hard disk is generally manipulated (created, erased, etc.) as a file via a file system.

  The data stored as files on the hard disk may contain important data that needs to be kept confidential, such as user's personal information. With this type of equipment, files are not stolen or leaked. It is necessary to take sufficient security measures.

  A problem that has been pointed out has been related to file deletion processing. For example, in a file deletion process in a general file system, only entry deletion of the file from the management table (FAT etc.) is performed, and actual data remains in the hard disk as it is. For this reason, there is a risk that even the data that the user intends to delete is stolen by a malicious third party.

  Although it is unlikely that data will be stolen by general operations performed from the operation panel or host computer, the contents can be referred to by intentionally removing the hard disk from the device and connecting it to a computer etc. Remains. In the normal deletion process described above, for example, even if a file has been deleted after the end of the print job, the actual file data remains recorded on the disk, and sector data may be dumped (or considerably There is a possibility that the original data can be restored.

  As a general countermeasure against this problem, the data area that is no longer needed on the hard disk is filled with another meaningless data (such as “0” or “0xFF”) and overwritten. Processing for deleting confidential data so that it cannot be referred to is known. This process is referred to as “erase process” in the present specification, in distinction from the above “normal” deletion process.

There are various methods for when this erasing process is performed. For example, conventionally, a configuration in which an erasure process is performed immediately when corresponding data is no longer necessary, or a configuration in which a specific operation is performed is known (for example, Patent Document 1 below). In addition, a configuration is known in which an unexecuted portion of the erasure process is recorded and the unexecuted portion is erased when the device is turned on or off (for example, Patent Document 2 below).
JP 2005-96082 A JP 2005-117377 A

  However, in the above-described prior art, in the configuration in which the erasure process is performed immediately after the corresponding data is printed out and becomes unnecessary, assuming that the parallel process is not performed, the subsequent process is performed until the erasure process is completed. I can't do it. As a result, there arises a problem that a subsequent process is kept waiting until the erasing process is completed. Alternatively, even if the erasing process is performed by parallel processing, there arises a problem that the load on the entire system is increased in combination with subsequent processes. This is not a problem when the amount of data to be erased is small, but it takes a considerable amount of time to erase large data, which is a major problem when the user is in a hurry.

  Further, in the configuration in which the erasing process is performed at the timing when a specific operation is performed, the user must be aware of the operation, and if the operation is inadvertently forgotten, the erasing process is not performed. In addition, in the configuration in which the unexecuted portion is erased in synchronization with the power on or off of the device, there is a problem that the processing time for power on or off increases.

  In the configurations described in Patent Document 1 and Patent Document 2 described above, when the timing for performing the erasure process comes, only the HDD blocks occupied by undeleted files are erased at that time. . For example, such processing can be read from the description of paragraph 0047 of Patent Document 1, S117 of FIG. 5, FIG. 5, FIG. 6, paragraphs 0111 and 0119 of Patent Document 2, and the like.

  However, it is normal that a situation occurs in which the created new file has already been deleted by the time when the erasing process is performed. Therefore, in the configurations as in Patent Document 1 and Patent Document 2, there is a problem in that data erasure is not performed for an area occupied by a file that has already been deleted.

  In the above, the erasing process in the printer has been considered, but the same problem occurs similarly when the above-described conventional technique is applied to an information processing apparatus other than a printer using a nonvolatile storage device such as an HDD.

  An object of the present invention is to solve the above-mentioned problems, reliably without affecting the other information processing, delaying the other information processing, and forgetting to erase due to an operation error or the like. It is to be able to perform erasure processing on all the data occupied by the file above.

  In order to solve the problem, the present invention includes a nonvolatile storage device that stores input data as a file, the file data is stored in a data storage unit of the nonvolatile storage device, and file management of the nonvolatile storage device An information processing apparatus that is managed via management information of a storage unit and performs an erasure process for erasing an area occupied by the file on the data storage unit after the file stored in the nonvolatile storage device becomes unnecessary In the control method of the information processing device and the control program of the information processing device, when the file stored in the non-volatile storage device is no longer necessary, a deletion process for deleting the management information in the file management storage unit is performed, Storing erasure management information indicating an area occupied by the file on the data storage unit in the erasure management information storage unit; Then, when overwriting the area occupied by the file in the data storage unit in order to store another file in the nonvolatile storage device, a process of excluding that area from the erasure management information in the erasure management information storage unit is performed. When the opportunity to perform the erasure process comes, the erasure process for erasing the area on the data storage unit corresponding to the erasure management information of the erasure management information storage unit using predetermined meaningless data It was adopted.

  According to the above configuration, the file is surely occupied on the non-volatile storage device without affecting other information processing, delaying other information processing, and forgetting to delete due to an operation error. It is possible to perform erasure processing on all the data.

  Hereinafter, as an example of the best mode for carrying out the invention, an embodiment relating to a printer will be described.

  In the present embodiment, a description will be mainly given of a configuration in which data in the hard disk is erased at the timing when the device shifts to the power saving mode.

  FIG. 1 shows the configuration of a control system of a printer employing the present invention. In FIG. 1, reference numeral 1 denotes an operation unit for instructing execution of various functions of the device such as a print instruction. The operation unit 1 includes a plurality of keys, buttons, switches, and the like.

  Reference numeral 2 denotes a display unit for notifying the user of the state of the device and various operation results. The display unit 2 includes a liquid crystal panel, an LED, and the like.

  Reference numeral 3 denotes a communication unit that communicates with an external device such as a host computer. The communication unit 3 includes one or more of various interfaces such as a parallel port (IEEE1284, etc.), a network (CSMA / CD (Ethernet: registered trademark)), USB, and the like. The communication unit 3 is used when inputting print data from an external device such as a host computer or when performing various operations related to printing without using the operation unit 1.

  Reference numeral 4 denotes a printing unit that executes printing. The printing unit 4 includes a paper feeding mechanism, a drawing mechanism, and the like, and executes printing of data processed from the control unit 5. Each mechanism is equipped with various detection devices, and can detect various operation errors such as paper out, paper jam, out of ink, and cover open.

  Reference numeral 5 denotes a control unit that executes each function of the device. The control unit 5 controls various output operations corresponding to various input operations from the operation unit 1 and the communication unit 3. Various control procedures are stored in the control program storage unit 61 in the ROM 6. The control unit 5 includes a CPU and its peripheral chip set.

  Reference numeral 6 denotes a ROM that is a kind of storage device, and includes a control program storage unit 61 that stores a program executed by the control unit 5.

  Reference numeral 7 denotes a RAM which is a kind of storage device. RAM is an abbreviation for random access memory, and is a volatile storage device. The RAM 7 includes a buffer 71 used when handling a large amount of data such as print data, a work area 72 for temporarily storing variables necessary for the control unit 5 to perform various controls, and the like. .

  Reference numeral 8 denotes an HDD which is a kind of storage device. HDD is an abbreviation for hard disk drive, and is composed of a hard disk that is a nonvolatile storage device and a mechanism for driving the hard disk.

  The HDD 8 includes a print data storage unit 81 that stores print data input via the communication unit 3 as a file, a file management storage unit 82 that stores management information on files stored in the print data storage unit 81, and the like. It is defined. Further, the HDD 8 stores user setting values and the like, and includes an erasure time setting storage unit 83 that stores a time at which erasure processing is to be executed.

  The print data storage unit 81 corresponds to an HDD file storage area in a normal file system, and the file management storage unit 82 corresponds to a file data management information storage area called FAT or inode in various OS file systems.

  As described above, in the normal deletion process, only the entry in the file management storage unit 82 of the target file is deleted. As a result, the target file cannot be accessed, and the area occupied by the target file on the print data storage unit 81 can be overwritten.

  Therefore, the general file access method cannot access the deleted file. However, as described above, even if the entry of the file management storage unit 82 is lost, the portion where the target file has been occupied on the print data storage unit 81 is not overwritten with another data. , There is a possibility to restore the original data. For such an operation, a special method such as a method of removing the HDD 8 and connecting it to a computer or the like and dumping the entire print data storage unit 81 is usually used. However, in some cases, for example, a bug that exists in the interface program of the communication unit 3 or the like can be hacked to directly dump the print data storage unit 81 from the outside via the communication unit 3. There are also cases where In general, it cannot be guaranteed that such a security hole has been completely removed.

  Therefore, this type of device is required to be able to perform the above-described “erasing process” that completely disables the file data on the print data storage unit 81. The control of the erasing process in this embodiment will be described later in more detail.

  In FIG. 1 again, reference numeral 9 denotes an EEPROM which is a kind of storage device. The EEPROM 9 is a non-volatile storage device that stores the state of the device, the setting value of the user, and the like. In the present embodiment, an erasure management information storage unit 91 is provided in the EEPROM 9, and the erasure management information storage unit 91 stores information on the area to be erased as one item of the state of the device to be stored.

  In addition, as one item of user setting values to be stored in the EEPROM 9, there is a power saving setting storage unit 92 that stores an interval of time during which the device should shift to a power saving state. The user setting value storage unit exists in both the HDD 8 and the EEPROM 9, but which setting value is allocated to which can be determined appropriately according to the situation.

  Reference numeral 10 denotes a time measuring unit for measuring and managing the passage of time. The timer unit 10 includes a timer mechanism and a real time clock mechanism. Normally, the timer mechanism measures the passage of relative time, and the real-time clock mechanism counts the passage of absolute time.

  FIG. 2 shows an example of the internal configuration of the print data storage unit 81 shown in FIG.

  Print data received via the communication unit 3 is stored in the print data storage unit 81. In general, print data received by one communication process is regarded as one unit, and this is called a print job. Each job is stored as a file in the hard disk. Each file is given a unique name and managed by that name. In the example of FIG. 2, reference numeral 21 is stored as a file having a file name “A1.TIF”, 22 is “B2.JPG”, and 23 is “C3.TIF”. The file name information itself is not stored in the print data storage unit 81 but is stored in the file management storage unit 82. As for the contents of each file, the received data may be stored as it is, or the result of appropriately processing it may be stored.

  FIG. 3 shows an example of the internal configuration of the file management storage unit 82 of FIG. The file management storage unit 82 stores management information related to the print data file stored in the print data storage unit 81.

  This management information is composed of four items shown in 31 to 34 per file, and these four items are collectively called a record. Reference numeral 31 denotes a file name item storing a file name which is an identifier of each print job. In FIG. 3, three file names “A1.TIF”, “B2.JPG”, and “C3.TIF” are stored as file name items 31 corresponding to the example of FIG.

  Reference numeral 32 denotes a data size information item storing the data size of each file. The unit of numerical values to be stored in the data size information item 32 is determined based on a certain standard. For this unit, for example, a unit of bytes or a unit of size such as a sector or a cylinder on the HDD is used.

  Reference numeral 33 denotes a start address information item storing address information indicating a location where each file is stored in the print data storage unit 81. The unit of the numerical value representing the address information is also determined based on a certain standard (for example, the sector address of the HDD).

  Reference numeral 34 denotes a job attribute information item indicating a print job attribute. In this embodiment, the job attribute information item 34 can define the attribute of each job.

  In this embodiment, for a certain file, a file attribute “deletion designated but no erasure process is executed” can be stored in the job attribute information item 34. Hereinafter, a file in which the file attribute “deletion is specified but the deletion process is not executed” is stored in the job attribute information item 34 is referred to as a “deletion waiting job”. For example, it is assumed that a job attribute information item 34 having a value (of a certain bit) of “1” is a job waiting for deletion and a job having a value of “0” is a normal job. The storage location of specific print data, its storage capacity and attributes can be determined from the four management information shown in 31-34.

  The job attribute information item 34 can store any attribute other than the above-mentioned job waiting for deletion / normal job by appropriately determining the correspondence with the bit position or determining the storage format. it can.

  In the example of FIG. 3, management information stores one record per file, but in some cases, one (large) file is divided and stored in a plurality of data areas (clusters, blocks, etc.). In some cases. Further, the plurality of data areas may be recorded on non-contiguous blocks on the HDD. In such a case, one file is divided into a plurality of records and stored in the file management storage unit 82. In any case, it is necessary to store records in the file management storage unit 82 for all file data. When file data is stored in a plurality of data areas, each record can link to the next record. A simple chain structure is used.

  In FIG. 3, corresponding to the example of FIG. 2, the record 35 is for the file “A1.TIF” (21), the record 36 is for the file “B2.JPG” (22), and the record 37 is the file “C3.TIF. "Management information is stored for (23)." A blank record indicating the end is stored at the end of all records. In this embodiment, blank records are set to 0 for all items as indicated by reference numeral 38 (however, the data format of blank records is arbitrary). By detecting this blank record, it is possible to detect whether the last job has been read, and to perform processing such as counting the total number of stored job files.

  FIG. 4 shows an example of the internal configuration of the erasure management information storage unit 91 described above. As shown in the figure, the erasure management information storage unit 91 stores management information indicating an area in the print data storage unit 81 where erasure processing should be performed. The management information is composed of two items denoted by reference numerals 41 to 42 per record, and these two items are collectively referred to as a record.

  In FIG. 4, reference numeral 41 denotes a data size information item storing the data size of each area. The content of the data size information item 41 is a copy of the data size information item 32 in the file management storage unit 82 of FIG. 3, and has the same meaning.

  Reference numeral 42 denotes a start address information item that stores address information of each area in the print data storage unit 81. The content of the start address information item 42 is a copy of the start address information item 33 in the file management storage unit 82 of FIG. 3, and has the same meaning.

  Each of the records 43 and 44 has the above-described configuration. Among these, the record 43 stores 21 areas “A1.TIF” shown in the example of FIG. 2, and the record 44 contains 22 areas shown in the example of FIG. “B2. JPG” is stored. In addition, there is a blank record indicating the end of all records. The content of the blank record is 0 as shown in 45 in the data size information item 41. By detecting this blank record, the number of all data areas can be detected. Naturally, one record in FIG. 4 is stored corresponding to one record in FIG.

  FIG. 5 is a flowchart showing a control procedure after the power is turned on in this embodiment. The process in FIG. 5 is started when the user turns on the power switch of the printer. The control procedure in FIG. 5 is stored in the control program storage unit 61, for example.

  In step S101, device initialization processing is performed. This initialization processing includes software processing such as a control program and hardware processing of various devices in the device, and performs processing so that the mechanisms such as the communication unit 3 and the printing unit 4 can be used. It is.

  In step S102, the process waits for an event to be processed. This event is an event that causes a change in the state of the device, and means an operation of the device by the user, a change in the state of the device due to the operation of the device, or the like. Specifically, an event occurs when the user operates the operation unit 1 or when an instruction is sent to the device via the communication unit 3. In addition, an event also occurs for an event such as a change in the state of the device, for example, detection of a printer out of ink, or a paper jam in the transport mechanism. In this apparatus, various processes corresponding to these events are performed (however, it is not possible to cope with unpredictable power-off events such as a power failure).

  In step S103, it is checked whether or not the event that occurred in step S102 has passed the transition time to the power saving mode. If so, the process proceeds to step S114, and if not, the process proceeds to step S104.

  Further, while waiting for an event, the elapsed time is counted up by the counter mechanism existing in the timing unit 10, but in step S102, whether or not the value of one of the sleep counters reaches a certain set value. Determine. The set value to be compared here is a set value of the transition time to the power saving mode stored in the power saving setting storage unit 92. When the value of the sleep counter reaches this set value, an event occurs and the process proceeds to step S103.

  The power saving setting storage unit 92 stores a plurality of types of user setting items such as a time for shifting to the power saving mode and a power saving execution flag indicating whether or not to shift to the power saving mode. This power saving setting storage can be stored in another nonvolatile storage device such as the HDD 8 when the EEPROM 9 is not present.

  In step S104, event processing other than the transition time to the power saving mode is executed. As an example of such an event, there is processing corresponding to each instruction such as printing or status display depending on the contents of the data received via the communication unit 3. In this case, there is a process of opening a file in which the received print data is to be recorded in the print data storage unit 81, adding print data to the file, and deleting a file that is no longer necessary upon completion of the process. Included (see steps S109 to S105 below).

  Examples of other events to be processed in step S104 include phenomena such as printer out of ink and paper jam. For these events, printing is interrupted or stopped, and a display unit is displayed to the user. In Step 2, perform a process such as generating a warning.

  In step S105, it is checked whether it is necessary to delete the print data file in the HDD 8 as a result of the event processing in step S104. If it is necessary to delete the file, the process proceeds to step S106; otherwise, the process proceeds to step S109.

  In step S106, the file management storage unit 82 is searched for information on the file determined to be deleted in step S104. Since the identification of each data file is normally managed by the file name, the file name 31 item in the file management storage unit 82 is checked, and a file name having the same name as the file name to be deleted generated in step S104 is obtained. Search for the record you have. In addition, when the file is large and data is stored in a plurality of data areas (clusters, blocks, etc.) as described above, there may be a plurality of corresponding records.

  In step S107, the record information retrieved in step S106 is copied and stored in the erasure management information storage unit 91. Specifically, first, a new record is added to the erasure management information storage unit 91. Next, the contents of the data size information item 32 of the corresponding record in the file management storage unit 82 are copied and stored in the data size information item 41 of the newly added record. Next, the contents of the start address information item 33 in the file management storage unit 82 are copied and stored in the start address information item 42 of the newly added record.

  For example, in the example of FIG. 3, it is assumed that a record 35 is detected as a record to be deleted. In this case, a new record is added to the erasure management information storage unit 91, and the content “300” of the data size information item 32 of the record 35 is stored in the data size information item 41. Further, the content “0” of the start address information item 33 of the record 35 is stored in the start address information item 42 of the new record. As a result, it is stored as a record 43 in FIG. If a plurality of records to be deleted are detected, the same processing is performed for all the records.

  In step S108, the record searched in step S106 is deleted from the file management storage unit 82. Specifically, the contents of all items of the corresponding record are overwritten with meaningless values, for example, all “0” (or 0xFF, etc.). Then, the content of the job attribute information item 34 of the corresponding record is changed to the “invalid” state.

  By the processing in step S108, control is performed so as to ignore all file operations for the record (corresponding file) of this attribute in the future. In addition, when a new record addition request is made, overwriting of the record with this attribute to the storage area is permitted. After step S108, the process returns to step S102 and waits for the next event to occur.

  In step S109, it is checked whether or not a print data file addition process has been performed in the HDD 8 as a result of the event process in step S104. Note that “addition processing” in steps S109 to S113 means processing for adding data to a file opened in response to the event generated in step S104. If file addition processing is necessary, the process proceeds to step S110. Otherwise, the process returns to step S102 and waits for the next event to occur.

  In step S110, the file management storage unit 82 is searched for information on the file added in step S104. Since the identification of each data file is normally managed by the file name, the file name 31 item in the file management storage unit 82 is checked, and the record having the same name as the file name added in step S104 Search for. In some cases, there may be a plurality of corresponding records.

  In step S111, the data area indicated by the record searched in step S110 is compared with the area indicated by each record in the erasure management information storage unit 91. In step S112, it is checked whether or not these areas overlap. At this time, each area can be calculated from the data size information item 32 and the start address information item 33 indicated by each record, or from the data size information item 41 and the start address information item 42. This investigation is performed for all records in the erasure management information storage unit 91, and even when there are a plurality of overlapping portions, all are extracted and the results are temporarily stored in the work area 72.

  As a result of the duplication inspection in step S112, if an overlapping area is detected, the process proceeds to step S113. If no overlapping area is detected, the process returns to step S102 to generate the next event. wait.

  In step S113, the contents stored in the erasure management information storage unit 91 are updated based on the result detected in step S111. Specifically, a process of excluding an area overlapping with an area used in a newly added file from each record in the erasure management information storage unit 91 is performed. Records in which the entire area is used are deleted from the erasure management information storage unit 91, and the registration contents are adjusted so that a record in which a part of the area is used indicates only the unused area. Of course, the erasure process should not be performed on the area used in the newly added file, so this process is performed.

  On the other hand, if the event generated in step S102 in step S103 is an event indicating that the transition time to the power saving mode has elapsed, the process proceeds to step S114, and the erasure process in steps S114 to S116 is performed.

  In step S114, it is checked whether a record is registered in the erasure management information storage unit 91. If there is a record in the erasure management information storage unit 91, the process proceeds to step S115, and if not, the process proceeds to step S119. Whether or not a record is registered can be determined by whether or not the content of the data size information item 41 of the first record in the erasure management information storage unit 91 is not zero.

  In step S115, the data area indicated by the first record in the erase management information storage unit 91 is erased. For example, in the example of FIG. 4, an area is detected on the print data storage unit 81 corresponding to the data size information item 41 and the start address information item 42 of the record 43.

  In the example of the record 43, it is detected that the area corresponding to the data size “300” starting from the start address “0” corresponds to this. This area corresponds to the area 21 in the example of FIG. Next, an erasing process is performed on the area detected on the print data storage unit 81. As described above, in the erasing process, there is a method of writing meaningless data (“0”, “0xFF”, etc.) to all data. Further, a method of writing randomly generated data or performing a writing process a plurality of times may be employed.

  In step S116, the record corresponding to the area that has been erased in step S115 is deleted from the erase management information storage unit 91. Specifically, for example, a pointer value indicating a valid record is set to indicate the next record. Alternatively, the erasure management information storage unit 91 is reconfigured so that the second and subsequent records are shifted forward one by one. In step S117, it is checked whether an event has occurred in the device. If an event has occurred, the process proceeds to step S118. If not, the process returns to step S114 to process the next record. If an event has occurred in the device, the transition to the power saving mode and the continuation process of the erasure waiting area are stopped.

  In step S118, the value of the sleep counter is initialized. This is processed in order to newly start the count of sleep because the event is detected in step S117 and the shift to the power saving mode is stopped. The event detected at step S117 is analyzed and executed after step S103.

  In step S119, it is checked whether or not to shift to the power saving mode. If the mode is shifted to the power saving mode, the process proceeds to step S120, and if not, the process proceeds to step S118.

  The user setting whether to use the power saving function may be stored as, for example, a power saving execution flag in the power saving setting storage unit 92. Refer to the setting contents for determining whether to enter the power saving mode. Is done. If the setting is not shifted, the process proceeds to step S118, the value of the sleep counter is initialized, the process returns to step S102, and the process is continued.

  In step S120, control is performed so that the state of the device shifts from the normal power mode to the power saving mode. As a result, since the control unit 5 is also in the sleep state, the control by the CPU is stopped. When an event such as data reception from the host device via the communication unit 3 or an operation of the operation unit 1 by the user occurs, an interrupt signal is generated. The process proceeds to step S121.

  In step S121, control is performed so that the state of the device shifts from the power saving mode to the normal power mode. Thereafter, the process proceeds to step S118, the value of the sleep counter is initialized, and the process returns to step S102. Events occurring between step S120 and step S121 are analyzed and executed after step S103.

  As described above, according to the present embodiment, when the file stored in the HDD 8 becomes unnecessary, the deletion processing for deleting the management information in the file management storage unit 82 is performed, and the file is stored on the print data storage unit 81. Erase management information indicating the occupied area is stored in the erase management information storage unit 91. Thereafter, when another area is overwritten on the area occupied by the file in the print data storage unit 81 in order to store it in the HDD 8, a process of excluding that area from the deletion management information in the deletion management information storage section 91 is performed. Then, when an opportunity to perform the erasure process comes, an erasure process is performed to erase the area on the print data storage unit 81 corresponding to the erasure management information in the erasure management information storage unit 91 using predetermined meaningless data. It is like that.

  With this configuration, the area previously occupied by the file on the HDD 8 is always stored in the erasure management information storage unit 91 and can be surely erased completely. Absent.

  In addition, since the state in which the device is not used continues for a certain period of time and the transition process from the normal power state to the low power consumption state (power saving mode) is performed, the erasure process is performed, so that other information processing, For example, there is no problem of delaying the subsequent printing process or prolonging the power-on / off process.

  Further, when the file stored in the HDD 8 becomes unnecessary, the management information in the file management storage unit 82 is deleted, and when another file is overwritten on the data area occupied by the corresponding file, the area is deleted. A process of excluding it from the erasure management information in the management information storage unit 91 is performed. For this reason, the problem which damages the file in process (use) does not arise.

  In the above, the device is not used for a certain period of time, and the erasure process is executed at the timing of transition from the normal power state to the low power consumption state (power saving mode). As in Example 2, the erasing process in steps S114 to S117 may be performed at the user designated timing.

  In the present embodiment, a case will be described in which an erasure process is performed when a device reaches a designated time. Further, in the present embodiment, the processing at the time of requesting the deletion processing is different from the actual deletion operation, and only the pseudo deletion processing (invisibility processing) is performed, so that the confidentiality of data is maintained as compared with the first embodiment. Then, the effect is somewhat reduced. However, since it can be realized without requiring a storage device different from the HDD such as the EEPROM 9 in the first embodiment, there is an advantage that the manufacturing cost of the device can be kept low.

  Also in this embodiment, it is assumed that the hardware configuration of the apparatus shown in FIG. 1 is common. However, since the EEPROM 9 portion is not necessary in this embodiment, it is not necessary to mount it.

  Further, the internal configurations of the print data storage unit 81 in FIG. 2 and the file management storage unit 82 in FIG. 3 are assumed to be common in this embodiment.

  FIG. 6 is a flowchart showing a control procedure after the power is turned on in this embodiment. The process of FIG. 6 is started when the user turns on the printer power switch. The control procedure of FIG. 6 is stored in the control program storage unit 61, for example.

  In step S201, device initialization processing is performed. This initialization processing includes software processing such as a control program and hardware processing of various devices in the device, and performs processing so that the mechanisms such as the communication unit 3 and the printing unit 4 can be used. It is.

  In step S202, the process waits for an event to occur. This event is generated in response to an operation of the device by the user, an instruction to the device via the communication unit 3, an ink out detection, a paper jam, etc., as described with respect to step S102 in FIG. (However, it cannot respond to unpredictable power shutdown events such as power outages). In this apparatus, various processes are performed in response to these events.

  In step S203, it is checked whether the event that occurred in step S202 has reached a specified time. If so, the process proceeds to step S208. If not, the process proceeds to step S204. The designated time is the setting content stored in the erasure time setting storage unit 83, and is set by the user when the erasure process should be executed. The user can realize an effective process by setting the set value at a time when the device is expected not to be used, for example, at midnight. The time can be acquired by a real-time clock mechanism existing in the timer unit 10. This mechanism has an alarm function that issues an event when a specific time comes, and when this time becomes the same as the set time, an event occurs, and the process proceeds to step S203.

  In step S204, processing of events other than the arrival at the specified time is executed. As an example of such an event, when data is received via the communication unit 3, processing corresponding to each instruction such as printing or status display is executed according to the content of the received data. Another example is the occurrence of a phenomenon such as a printer running out of ink or a paper jam. In these cases, printing is interrupted or stopped, and processing such as generating a warning on the display unit 2 to the user is performed. carry out.

  In step S205, it is checked whether or not it is necessary to delete the print data file in the HDD 8 as a result of the event processing in step S204. If it is necessary to delete the file, the process proceeds to step S206. If not, the process returns to step S202 and waits for the next event to occur.

  In step S206, the file management storage unit 82 is searched for information on the file determined to be deleted in step S204. Since the identification of each data file is normally managed by a file name, the file name 31 item in the file management storage unit 82 is checked, and a file name having the same name as the name of the file to be deleted generated in step S204 is obtained. Search for the record you have. In some cases (such as when the file is large as described above), there may be a plurality of corresponding records.

  In step S207, the contents of the job attribute information item 34 of the record searched in step S206 are changed to the status of the job waiting for deletion. In the example of FIG. 3, the value is “1”. When there are a plurality of corresponding records, the same processing is performed for all the records. Further, in this embodiment, the contents of the job attribute information item 34 are changed to the state of the job waiting for deletion at the same time, and at the same time, this file is processed so as not to be shown to the user (invisible processing). Thereafter, the process returns to step S202 and waits for the next event to occur.

  By the above-described invisibility process, this file appears to the user as deleted. Such processing can be performed by using an invisible bit used in a file system of a specific OS. Normally, when such invisibility processing is performed, the contents of the record in the file management storage unit 82 are not reported for specific processing such as directory listing acquisition.

  However, in the state where only this invisibility is performed, the contents of the print data storage unit 81 which is the data portion corresponding to the file management storage unit 82 are actually left as they are, and a complete “deletion” state is entered. Not. For example, in the “invisible” state of many OS file systems, it is often possible to access the file as long as the file name is known. For this reason, compared to the case of performing “normal” deletion processing as in the first embodiment, there is a risk that the stored contents of the disc can be referred to before the following deletion processing is executed. A little bigger. In addition, since the data area of the file that is no longer necessary in the invisible state remains secured, there is a slight disadvantage in terms of disk utilization efficiency.

  On the other hand, if the event that occurred in step S202 in step S203 has reached the specified time, the process proceeds to step S208, and the erasure process in steps S208 to S211 is performed. In step S208, the file management storage unit 82 is checked to determine whether there is a job waiting for deletion. Specifically, the job attribute information item 34 of each record is examined, and it is determined whether or not there is an item that is “1” (waiting for deletion).

  In step S209, if there is a job waiting for deletion as a result of checking in step S208, the process proceeds to step S210. On the other hand, if there is no job waiting for deletion, the process returns to step S202 and waits for the next event to occur.

  In step S210, the data area indicated by the record detected in step S208 is erased. Specifically, in the example of FIG. 3, the record 35 is detected, and the corresponding area on the print data storage unit 81 is detected from the information of the data size information item 32 and the start address information item 33. In the example of the record 35, it is detected that an area starting from the start address “0” and occupying the data size “300” corresponds thereto. This area corresponds to the area 21 in the example of FIG. Next, an erasing process is performed on the detected area on the print data storage unit 81. As an example of the erasing process, there is a method of writing meaningless data (such as “0” or “0xFF”) to all data in the area. Further, a method of writing randomly generated data or performing a writing process a plurality of times may be employed.

  In step S211, the record detected in step S208 is (completely) deleted from the file management storage unit 82. Specifically, the contents of all items of the corresponding record are overwritten with meaningless values, for example, all “0”. Then, the content of the job attribute information item 34 of the corresponding record is changed to the “invalid” state. As a result, in the future, control is performed so as to ignore all file operations on the record (corresponding file) of this attribute. In addition, when a new record addition request is made, overwriting of the record with this attribute to the storage area is permitted. Thereafter, the process returns to step S208, and the process for the next job waiting for erasure is continued.

  As described above, in this embodiment, when a file becomes unnecessary, a file management storage unit is provided so that an attribute of waiting for deletion processing is given to the file and the file becomes invisible by a specific file operation. 82 management information is changed. That is, a file to be deleted is managed by using the deletion waiting attribute of the file management storage unit 82 and the invisibility processing.

  For this reason, it can be realized without the need for a storage device other than the HDD such as the erasure management information storage unit 91 of the first embodiment and the EEPROM 9 for storing it, and the manufacturing cost of the device can be kept low. Can do.

  Of course, also in this embodiment, the area occupied by the file on the HDD 8 in the past is recorded in the file management storage unit 82 and can be erased completely without fail. Does not occur.

  In this embodiment, the erasing process can be performed when the time specified by the user comes. For this reason, it is possible for the user to specify a time zone during which the device is not used much, such as at night or during breaks, and cause the erasure process to be performed, and this delays other important information processing and subsequent printing processes. Does not occur.

  In the present embodiment, the erasure process is performed at the user-specified timing. Of course, as in the first embodiment, the state in which the device is not used continues for a certain period of time, and the low power consumption is reduced from the normal power state. The erasing process may be executed at the timing of transition to the state (power saving mode).

  The present invention is not limited to the printer described above, and can be implemented in an information processing apparatus having a nonvolatile storage device such as a personal computer or a composite image processing apparatus. A control program necessary for carrying out the present invention can be stored in advance in a storage medium such as a ROM or HDD of these information processing apparatuses. Further, it can be installed / updated from a storage medium such as an MO or a CD-ROM. Further, when the information processing apparatus has a network interface, it can be supplied from an arbitrary server via the network.

1 is a block diagram illustrating a configuration of a printer that employs the present invention. FIG. 2 is an explanatory diagram illustrating an example of an internal configuration of a print data storage unit of the printer of FIG. 1. FIG. 2 is an explanatory diagram illustrating an example of an internal configuration of a file management storage unit of the printer of FIG. 1. FIG. 2 is an explanatory diagram illustrating an example of an internal configuration of an erasure management information storage unit of the printer of FIG. 1. FIG. 2 is a flowchart showing an outline of a control procedure of erasure processing in the printer of FIG. 1. FIG. 2 is a flowchart showing an outline of different erasing process control procedures in the printer of FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Operation part 2 Display part 3 Communication part 4 Printing part 5 Control part 6 ROM
61 Control program storage unit 7 RAM
71 Buffer 72 Work area 8 HDD
81 Print Data Storage Unit 82 File Management Storage Unit 83 Erase Time Setting Storage Unit 9 EEPROM
91 Erase Management Information Storage Unit 92 Power Saving Setting Storage Unit 10 Timekeeping Unit

Claims (11)

A non-volatile storage device for storing input data as a file, the file data is stored in a data storage unit of the non-volatile storage device, and is managed via management information in a file management storage unit of the non-volatile storage device; In the information processing apparatus for performing an erasing process for erasing an area occupied by the file on the data storage unit after the file stored in the nonvolatile storage device becomes unnecessary,
When the file stored in the non-volatile storage device is no longer needed, the deletion management is performed to delete the management information in the file management storage unit, and the deletion management indicating the area occupied by the file on the data storage unit Information is stored in the erasure management information storage unit,
Then, when overwriting the area occupied by the file in the data storage unit to store another file in the nonvolatile storage device, perform processing to exclude the area from the erasure management information of the erasure management information storage unit,
Control means for performing an erasure process for erasing an area on the data storage unit corresponding to the erasure management information of the erasure management information storage unit using predetermined meaningless data when an opportunity to perform the erasure process comes An information processing apparatus comprising: A non-volatile storage device for storing input data as a file, the file data is stored in a data storage unit of the non-volatile storage device, and is managed via management information in a file management storage unit of the non-volatile storage device; In the information processing apparatus for performing an erasing process for erasing an area occupied by the file on the data storage unit after the file stored in the nonvolatile storage device becomes unnecessary,
When the file stored in the non-volatile storage device becomes unnecessary, the file management storage unit is configured to give the file an attribute of waiting for erasure processing and to make the file invisible in a specific file operation Change the management information for
When an opportunity to perform the erasure process comes, the area on the data storage unit occupied by the file waiting for the erasure process in the file management storage unit is erased using predetermined meaningless data An information processing apparatus comprising control means for performing an erasing process.   The information processing apparatus according to claim 1, wherein an opportunity to perform the erasing process is a case where a state where the device is not used continues for a certain period of time.   The information processing apparatus according to claim 1, wherein the opportunity to perform the erasing process is a timing at which a transition from a normal power state to a low power consumption state occurs.   The information processing apparatus according to claim 1, wherein an opportunity to perform the erasing process is a time specified by a user. A non-volatile storage device for storing input data as a file, the file data is stored in a data storage unit of the non-volatile storage device, and is managed via management information in a file management storage unit of the non-volatile storage device; In the control method of the information processing apparatus for performing an erasing process for erasing the area occupied by the file on the data storage unit after the file stored in the nonvolatile storage device is no longer necessary,
When the file stored in the non-volatile storage device is no longer needed, the deletion management is performed to delete the management information in the file management storage unit, and the deletion management indicating the area occupied by the file on the data storage unit Information is stored in the erasure management information storage unit,
Then, when overwriting the area occupied by the file in the data storage unit to store another file in the nonvolatile storage device, perform processing to exclude the area from the erasure management information of the erasure management information storage unit,
When an opportunity to perform the erasure process comes, performing an erasure process for erasing an area on the data storage unit corresponding to the erasure management information of the erasure management information storage unit using predetermined meaningless data A control method for an information processing apparatus. A non-volatile storage device for storing input data as a file, the file data is stored in a data storage unit of the non-volatile storage device, and is managed via management information in a file management storage unit of the non-volatile storage device; In the control method of the information processing apparatus for performing an erasing process for erasing the area occupied by the file on the data storage unit after the file stored in the nonvolatile storage device is no longer necessary,
When the file stored in the non-volatile storage device becomes unnecessary, the file management storage unit is configured to give the file an attribute of waiting for erasure processing and to make the file invisible in a specific file operation Change the management information for
When an opportunity to perform the erasure process comes, the area on the data storage unit occupied by the file waiting for the erasure process in the file management storage unit is erased using predetermined meaningless data A method for controlling an information processing apparatus, comprising performing an erasing process.   8. The method of controlling an information processing apparatus according to claim 6, wherein the opportunity to perform the erasing process is a time specified by a user.   8. The information processing apparatus control method according to claim 6, wherein the erasing process is performed when the device is not used for a certain period of time.   The information processing apparatus control method according to claim 6 or 7, wherein the opportunity to perform the erasing process is a timing at which a transition from a normal power state to a low power consumption state occurs.   11. A control program for an information processing apparatus, which controls hardware constituting the information processing apparatus in order to carry out the control method for the information processing apparatus according to any one of claims 6 to 10.

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