dev_interface.h

   1 /*
   2  * dev_interface.h
   3  *
   4  * Home page of code is: http://smartmontools.sourceforge.net
   5  *
   6  * Copyright (C) 2008-9 Christian Franke <smartmontools-support@lists.sourceforge.net>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * (for example COPYING); If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17
  18 #ifndef DEV_INTERFACE_H
  19 #define DEV_INTERFACE_H
  20
  21 #define DEV_INTERFACE_H_CVSID "$Id: dev_interface.h 2973 2009-10-26 22:38:19Z chrfranke $\n"
  22
  23 #include <stdarg.h>
  24 #include <stdexcept>
  25 #include <string>
  26 #include <vector>
  27
  28 #if !defined(__GNUC__) && !defined(__attribute__)
  29 #define __attribute__(x)  /**/
  30 #endif
  31
  32 #ifdef _MSC_VER // Disable MSVC warning
  33 #pragma warning(disable:4250) // 'class1' : inherits 'class2::member' via dominance
  34 #endif
  35
  36 /////////////////////////////////////////////////////////////////////////////
  37 // Common functionality for all device types
  38
  39 // Forward declarations
  40 class smart_interface;
  41 class ata_device;
  42 class scsi_device;
  43
  44 /// Base class for all devices
  45 class smart_device
  46 {
  47 // Types
  48 public:
  49   /// Device info strings
  50   struct device_info {
  51     device_info()
  52       { }
  53     device_info(const char * d_name, const char * d_type, const char * r_type)
  54       : dev_name(d_name), info_name(d_name),
  55         dev_type(d_type), req_type(r_type)
  56       { }
  57
  58     std::string dev_name;  ///< Device (path)name
  59     std::string info_name; ///< Informal name
  60     std::string dev_type;  ///< Actual device type
  61     std::string req_type;  ///< Device type requested by user, empty if none
  62   };
  63
  64   /// Error (number,message) pair
  65   struct error_info {
  66     explicit error_info(int n = 0)
  67       : no(n) { }
  68     error_info(int n, const char * m)
  69       : no(n), msg(m) { }
  70     void clear()
  71       { no = 0; msg.erase(); }
  72
  73     int no;          ///< Error number
  74     std::string msg; ///< Error message
  75   };
  76
  77 // Construction
  78 protected:
  79   /// Constructor to init interface and device info.
  80   /// Must be called in implementation classes.
  81   smart_device(smart_interface * intf, const char * dev_name,
  82     const char * dev_type, const char * req_type);
  83
  84   /// Dummy enum for dummy constructor.
  85   enum do_not_use_in_implementation_classes { never_called };
  86   /// Dummy constructor for abstract classes.
  87   /// Must never be called in implementation classes.
  88   smart_device(do_not_use_in_implementation_classes);
  89
  90 public:
  91   virtual ~smart_device() throw();
  92
  93 // Attributes
  94 public:
  95   ///////////////////////////////////////////////
  96   // Dynamic downcasts to actual device flavor
  97
  98   /// Return true if ATA device
  99   bool is_ata() const
 100     { return !!m_ata_ptr; }
 101   /// Return true if SCSI device
 102   bool is_scsi() const
 103     { return !!m_scsi_ptr; }
 104
 105   /// Downcast to ATA device.
 106   ata_device * to_ata()
 107     { return m_ata_ptr; }
 108   /// Downcast to ATA device (const).
 109   const ata_device * to_ata() const
 110     { return m_ata_ptr; }
 111   /// Downcast to SCSI device.
 112   scsi_device * to_scsi()
 113     { return m_scsi_ptr; }
 114   /// Downcast to ATA device (const).
 115   const scsi_device * to_scsi() const
 116     { return m_scsi_ptr; }
 117
 118   ///////////////////////////////////////////////
 119   // Device information
 120
 121   /// Get device info struct.
 122   const device_info & get_info() const
 123     { return m_info; }
 124
 125   /// Get device (path)name.
 126   const char * get_dev_name() const
 127     { return m_info.dev_name.c_str(); }
 128   /// Get informal name.
 129   const char * get_info_name() const
 130     { return m_info.info_name.c_str(); }
 131   /// Get device type.
 132   const char * get_dev_type() const
 133     { return m_info.dev_type.c_str(); }
 134   /// Get type requested by user, empty if none.
 135   const char * get_req_type() const
 136     { return m_info.req_type.c_str(); }
 137
 138 protected:
 139   /// R/W access to device info struct.
 140   device_info & set_info()
 141     { return m_info; }
 142
 143 public:
 144   ///////////////////////////////////////////////
 145   // Last error information
 146
 147   /// Get last error info struct.
 148   const error_info & get_err() const
 149     { return m_err; }
 150   /// Get last error number.
 151   int get_errno() const
 152     { return m_err.no; }
 153   /// Get last error message.
 154   const char * get_errmsg() const
 155     { return m_err.msg.c_str(); }
 156
 157   /// Set last error number and message.
 158   /// Printf()-like formatting is supported.
 159   /// Returns false always to allow use as a return expression.
 160   bool set_err(int no, const char * msg, ...)
 161     __attribute__ ((format (printf, 3, 4)));
 162
 163   /// Set last error info struct.
 164   bool set_err(const error_info & err)
 165     { m_err = err; return false; }
 166
 167   /// Clear last error info.
 168   void clear_err()
 169     { m_err.clear(); }
 170
 171   /// Set last error number and default message.
 172   /// Message is retrieved from interface's get_msg_for_errno(no).
 173   bool set_err(int no);
 174
 175 // Operations
 176 public:
 177   ///////////////////////////////////////////////
 178   // Device open/close
 179   // Must be implemented in derived class
 180
 181   /// Return true if device is open.
 182   virtual bool is_open() const = 0;
 183
 184   /// Open device, return false on error.
 185   virtual bool open() = 0;
 186
 187   /// Close device, return false on error.
 188   virtual bool close() = 0;
 189
 190   /// Open device with autodetection support.
 191   /// May return another device for further access.
 192   /// In this case, the original pointer is no longer valid.
 193   /// Default Implementation calls 'open()' and returns 'this'.
 194   virtual smart_device * autodetect_open();
 195
 196   ///////////////////////////////////////////////
 197   // Support for tunnelled devices
 198
 199   /// Return true if other device is owned by this device.
 200   /// Default implementation returns false.
 201   virtual bool owns(const smart_device * dev) const;
 202
 203   /// Release ownership of other device.
 204   /// Default implementation does nothing.
 205   virtual void release(const smart_device * dev);
 206
 207 protected:
 208   /// Set dynamic downcast for ATA
 209   void this_is_ata(ata_device * ata);
 210     // {see below;}
 211
 212   /// Set dynamic downcast for SCSI
 213   void this_is_scsi(scsi_device * scsi);
 214     // {see below;}
 215
 216   /// Get interface which produced this object.
 217   smart_interface * smi()
 218     { return m_intf; }
 219   /// Get interface which produced this object (const).
 220   const smart_interface * smi() const
 221     { return m_intf; }
 222
 223 // Implementation
 224 private:
 225   smart_interface * m_intf;
 226   device_info m_info;
 227   ata_device * m_ata_ptr;
 228   scsi_device * m_scsi_ptr;
 229   error_info m_err;
 230
 231   // Prevent copy/assigment
 232   smart_device(const smart_device &);
 233   void operator=(const smart_device &);
 234 };
 235
 236
 237 /////////////////////////////////////////////////////////////////////////////
 238 // ATA specific interface
 239
 240 /// ATA register value and info whether is has been ever set
 241 // (Automatically set by first assignment)
 242 class ata_register
 243 {
 244 public:
 245   ata_register()
 246     : m_val(0x00), m_is_set(false) { }
 247
 248   ata_register & operator=(unsigned char val)
 249     { m_val = val; m_is_set = true; return * this; }
 250
 251   unsigned char val() const
 252     { return m_val; }
 253   operator unsigned char() const
 254     { return m_val; }
 255
 256   bool is_set() const
 257     { return m_is_set; }
 258
 259 private:
 260   unsigned char m_val; ///< Register value
 261   bool m_is_set; ///< true if set
 262 };
 263
 264 /// ATA Input registers (for 28-bit commands)
 265 struct ata_in_regs
 266 {
 267   // ATA-6/7 register names  // ATA-3/4/5        // ATA-8
 268   ata_register features;     // features         // features
 269   ata_register sector_count; // sector count     // count
 270   ata_register lba_low;      // sector number    // ]
 271   ata_register lba_mid;      // cylinder low     // ] lba
 272   ata_register lba_high;     // cylinder high    // ]
 273   ata_register device;       // device/head      // device
 274   ata_register command;      // command          // command
 275
 276   /// Return true if any register is set
 277   bool is_set() const
 278     { return (features.is_set() || sector_count.is_set()
 279       || lba_low.is_set() || lba_mid.is_set() || lba_high.is_set()
 280       || device.is_set() || command.is_set());                    }
 281 };
 282
 283 /// ATA Output registers (for 28-bit commands)
 284 struct ata_out_regs
 285 {
 286   ata_register error;
 287   ata_register sector_count;
 288   ata_register lba_low;
 289   ata_register lba_mid;
 290   ata_register lba_high;
 291   ata_register device;
 292   ata_register status;
 293
 294   /// Return true if any register is set
 295   bool is_set() const
 296     { return (error.is_set() || sector_count.is_set()
 297       || lba_low.is_set() || lba_mid.is_set() || lba_high.is_set()
 298       || device.is_set() || status.is_set());                      }
 299 };
 300
 301
 302 /// 16-bit alias to a 8-bit ATA register pair.
 303 class ata_reg_alias_16
 304 {
 305 public:
 306   ata_reg_alias_16(ata_register & lo, ata_register & hi)
 307     : m_lo(lo), m_hi(hi) { }
 308
 309   ata_reg_alias_16 & operator=(unsigned short val)
 310     { m_lo = (unsigned char) val;
 311       m_hi = (unsigned char)(val >> 8);
 312       return * this;                   }
 313
 314   unsigned short val() const
 315     { return m_lo | (m_hi << 8); }
 316   operator unsigned short() const
 317     { return m_lo | (m_hi << 8); }
 318
 319 private:
 320   ata_register & m_lo, & m_hi;
 321
 322   // References must not be copied.
 323   ata_reg_alias_16(const ata_reg_alias_16 &);
 324   void operator=(const ata_reg_alias_16 &);
 325 };
 326
 327
 328 /// ATA Input registers for 48-bit commands
 329 // See section 4.14 of T13/1532D Volume 1 Revision 4b
 330 //
 331 // Uses ATA-6/7 method to specify 16-bit registers as
 332 // recent (low byte) and previous (high byte) content of
 333 // 8-bit registers.
 334 //
 335 // (ATA-8 ACS does not longer follow this scheme, it uses
 336 // abstract registers with sufficient size and leaves the
 337 // actual mapping to the transport layer.)
 338 //
 339 struct ata_in_regs_48bit
 340 : public ata_in_regs   // "most recently written" registers
 341 {
 342   ata_in_regs prev;  ///< "previous content"
 343
 344   // 16-bit aliases for above pair.
 345   ata_reg_alias_16 features_16;
 346   ata_reg_alias_16 sector_count_16;
 347   ata_reg_alias_16 lba_low_16;
 348   ata_reg_alias_16 lba_mid_16;
 349   ata_reg_alias_16 lba_high_16;
 350
 351   /// Return true if 48-bit command
 352   bool is_48bit_cmd() const
 353     { return prev.is_set(); }
 354
 355   /// Return true if 48-bit command with any nonzero high byte
 356   bool is_real_48bit_cmd() const
 357     { return (   prev.features || prev.sector_count
 358               || prev.lba_low || prev.lba_mid || prev.lba_high); }
 359
 360   ata_in_regs_48bit();
 361 };
 362
 363
 364 /// ATA Output registers for 48-bit commands
 365 struct ata_out_regs_48bit
 366 : public ata_out_regs   // read with HOB=0
 367 {
 368   ata_out_regs prev;  ///< read with HOB=1
 369
 370   // 16-bit aliases for above pair.
 371   ata_reg_alias_16 sector_count_16;
 372   ata_reg_alias_16 lba_low_16;
 373   ata_reg_alias_16 lba_mid_16;
 374   ata_reg_alias_16 lba_high_16;
 375
 376   ata_out_regs_48bit();
 377 };
 378
 379
 380 /// Flags for each ATA output register
 381 struct ata_out_regs_flags
 382 {
 383   bool error, sector_count, lba_low, lba_mid, lba_high, device, status;
 384
 385   /// Return true if any flag is set.
 386   bool is_set() const
 387     { return (   error || sector_count || lba_low
 388               || lba_mid || lba_high || device || status); }
 389
 390   /// Default constructor clears all flags.
 391   ata_out_regs_flags()
 392     : error(false), sector_count(false), lba_low(false), lba_mid(false),
 393       lba_high(false), device(false), status(false) { }
 394 };
 395
 396
 397 /// ATA pass through input parameters
 398 struct ata_cmd_in
 399 {
 400   ata_in_regs_48bit in_regs;  ///< Input registers
 401   ata_out_regs_flags out_needed; ///< True if output register value needed
 402   enum { no_data = 0, data_in, data_out } direction; ///< I/O direction
 403   void * buffer; ///< Pointer to data buffer
 404   unsigned size; ///< Size of buffer
 405
 406   /// Prepare for 28-bit DATA IN command
 407   void set_data_in(void * buf, unsigned nsectors)
 408     {
 409       buffer = buf;
 410       in_regs.sector_count = nsectors;
 411       direction = data_in;
 412       size = nsectors * 512;
 413     }
 414
 415   /// Prepare for 28-bit DATA OUT command
 416   void set_data_out(const void * buf, unsigned nsectors)
 417     {
 418       buffer = const_cast<void *>(buf);
 419       in_regs.sector_count = nsectors;
 420       direction = data_out;
 421       size = nsectors * 512;
 422     }
 423
 424   /// Prepare for 48-bit DATA IN command
 425   void set_data_in_48bit(void * buf, unsigned nsectors)
 426     {
 427       buffer = buf;
 428       // Note: This also sets 'in_regs.is_48bit_cmd()'
 429       in_regs.sector_count_16 = nsectors;
 430       direction = data_in;
 431       size = nsectors * 512;
 432     }
 433
 434   ata_cmd_in();
 435 };
 436
 437 /// ATA pass through output parameters
 438 struct ata_cmd_out
 439 {
 440   ata_out_regs_48bit out_regs; ///< Output registers
 441
 442   ata_cmd_out();
 443 };
 444
 445 /// ATA device access
 446 class ata_device
 447 : virtual public /*extends*/ smart_device
 448 {
 449 public:
 450   /// ATA pass through.
 451   /// Return false on error.
 452   /// Must be implemented in derived class.
 453   virtual bool ata_pass_through(const ata_cmd_in & in, ata_cmd_out & out) = 0;
 454
 455   /// ATA pass through without output registers.
 456   /// Return false on error.
 457   /// Calls ata_pass_through(in, dummy), cannot be reimplemented.
 458   bool ata_pass_through(const ata_cmd_in & in);
 459
 460   /// Return true if OS caches ATA identify sector.
 461   /// Default implementation returns false.
 462   virtual bool ata_identify_is_cached() const;
 463
 464 protected:
 465   /// Check command input parameters.
 466   /// Calls set_err(...) accordingly.
 467   bool ata_cmd_is_ok(const ata_cmd_in & in,
 468     bool data_out_support = false,
 469     bool multi_sector_support = false,
 470     bool ata_48bit_support = false);
 471
 472   /// Default constructor, registers device as ATA.
 473   ata_device()
 474     : smart_device(never_called)
 475     { this_is_ata(this); }
 476 };
 477
 478
 479 /////////////////////////////////////////////////////////////////////////////
 480 // SCSI specific interface
 481
 482 struct scsi_cmnd_io;
 483
 484 /// SCSI device access
 485 class scsi_device
 486 : virtual public /*extends*/ smart_device
 487 {
 488 public:
 489   /// SCSI pass through.
 490   /// Returns false on error.
 491   virtual bool scsi_pass_through(scsi_cmnd_io * iop) = 0;
 492
 493 protected:
 494   /// Default constructor, registers device as SCSI.
 495   scsi_device()
 496     : smart_device(never_called)
 497     { this_is_scsi(this); }
 498 };
 499
 500
 501 /////////////////////////////////////////////////////////////////////////////
 502
 503 // Set dynamic downcasts
 504 // Note that due to virtual inheritance,
 505 // (ata == this) does not imply ((void*)ata == (void*)this))
 506
 507 inline void smart_device::this_is_ata(ata_device * ata)
 508 {
 509   m_ata_ptr = (ata == this ? ata : 0);
 510 }
 511
 512 inline void smart_device::this_is_scsi(scsi_device * scsi)
 513 {
 514   m_scsi_ptr = (scsi == this ? scsi : 0);
 515 }
 516
 517
 518 /////////////////////////////////////////////////////////////////////////////
 519 /// Smart pointer class for device pointers
 520
 521 template <class Dev>
 522 class any_device_auto_ptr
 523 {
 524 public:
 525   typedef Dev device_type;
 526
 527   /// Construct from optional pointer to device
 528   /// and optional pointer to base device.
 529   explicit any_device_auto_ptr(device_type * dev = 0,
 530                                smart_device * base_dev = 0)
 531     : m_dev(dev), m_base_dev(base_dev) { }
 532
 533   /// Destructor deletes device object.
 534   ~any_device_auto_ptr() throw()
 535     { reset(); }
 536
 537   /// Assign a new pointer.
 538   /// Throws if a pointer is already assigned.
 539   void operator=(device_type * dev)
 540     {
 541       if (m_dev)
 542         fail();
 543       m_dev = dev;
 544     }
 545
 546   /// Delete device object and clear the pointer.
 547   void reset()
 548     {
 549       if (m_dev) {
 550         if (m_base_dev && m_dev->owns(m_base_dev))
 551           m_dev->release(m_base_dev);
 552         delete m_dev;
 553       }
 554       m_dev = 0;
 555     }
 556
 557   /// Return the pointer and release ownership.
 558   device_type * release()
 559     {
 560       device_type * dev = m_dev;
 561       m_dev = 0;
 562       return dev;
 563     }
 564
 565   /// Replace the pointer.
 566   /// Used to call dev->autodetect_open().
 567   void replace(device_type * dev)
 568     { m_dev = dev; }
 569
 570   /// Return the pointer.
 571   device_type * get() const
 572     { return m_dev; }
 573
 574   /// Pointer dereferencing.
 575   device_type & operator*() const
 576     { return *m_dev; }
 577
 578   /// Pointer dereferencing.
 579   device_type * operator->() const
 580     { return m_dev; }
 581
 582   /// For (ptr != 0) check.
 583   operator bool() const
 584     { return !!m_dev; }
 585
 586   /// For (ptr == 0) check.
 587   bool operator !() const
 588     { return !m_dev; }
 589
 590 private:
 591   device_type * m_dev;
 592   smart_device * m_base_dev;
 593
 594   void fail() const
 595     { throw std::logic_error("any_device_auto_ptr: wrong usage"); }
 596
 597   // Prevent copy/assignment
 598   any_device_auto_ptr(const any_device_auto_ptr<Dev> &);
 599   void operator=(const any_device_auto_ptr<Dev> &);
 600 };
 601
 602 typedef any_device_auto_ptr<smart_device> smart_device_auto_ptr;
 603 typedef any_device_auto_ptr<ata_device>   ata_device_auto_ptr;
 604 typedef any_device_auto_ptr<scsi_device>  scsi_device_auto_ptr;
 605
 606
 607 /////////////////////////////////////////////////////////////////////////////
 608 // smart_device_list
 609
 610 /// List of devices for DEVICESCAN
 611 class smart_device_list
 612 {
 613 // Construction
 614 public:
 615   smart_device_list()
 616     { }
 617
 618   ~smart_device_list() throw()
 619     {
 620       for (unsigned i = 0; i < m_list.size(); i++)
 621         delete m_list[i];
 622     }
 623
 624 // Attributes
 625   unsigned size() const
 626     { return m_list.size(); }
 627
 628 // Operations
 629   void clear()
 630     {
 631       for (unsigned i = 0; i < m_list.size(); i++)
 632         delete m_list[i];
 633       m_list.clear();
 634     }
 635
 636
 637   void push_back(smart_device * dev)
 638     { m_list.push_back(dev); }
 639
 640   void push_back(smart_device_auto_ptr & dev)
 641     {
 642       m_list.push_back(dev.get());
 643       dev.release();
 644     }
 645
 646   smart_device * at(unsigned i)
 647     { return m_list.at(i); }
 648
 649   const smart_device * at(unsigned i) const
 650     { return m_list.at(i); }
 651
 652   smart_device * release(unsigned i)
 653     {
 654       smart_device * dev = m_list.at(i);
 655       m_list[i] = 0;
 656       return dev;
 657     }
 658
 659 // Implementation
 660 private:
 661   std::vector<smart_device *> m_list;
 662
 663   // Prevent copy/assigment
 664   smart_device_list(const smart_device_list &);
 665   void operator=(const smart_device_list &);
 666 };
 667
 668
 669 /////////////////////////////////////////////////////////////////////////////
 670 // smart_interface
 671
 672 /// The platform interface abstraction
 673 class smart_interface
 674 {
 675 public:
 676   /// Initialize platform interface and register with smi().
 677   /// Must be implemented by platform module and register interface with set()
 678   static void init();
 679
 680   smart_interface()
 681     { }
 682
 683   virtual ~smart_interface() throw()
 684     { }
 685
 686   /// Return info string about build host and/or OS version.
 687   /// Default implementation returns SMARTMONTOOLS_BUILD_HOST.
 688   virtual std::string get_os_version_str();
 689
 690   /// Return valid args for device type option/directive.
 691   /// Default implementation returns "ata, scsi, sat, usb*..."
 692   /// concatenated with result from get_valid_custom_dev_types_str().
 693   virtual std::string get_valid_dev_types_str();
 694
 695   /// Return example string for program 'appname'.
 696   /// Default implementation returns empty string.
 697   /// For the migration of print_smartctl_examples(),
 698   /// function is allowed to print examples to stdout.
 699   /// TODO: Remove this hack.
 700   virtual std::string get_app_examples(const char * appname);
 701
 702   ///////////////////////////////////////////////
 703   // Last error information
 704
 705   /// Get last error info struct.
 706   const smart_device::error_info & get_err() const
 707     { return m_err; }
 708   /// Get last error number.
 709   int get_errno() const
 710     { return m_err.no; }
 711   /// Get last error message.
 712   const char * get_errmsg() const
 713     { return m_err.msg.c_str(); }
 714
 715   /// Set last error number and message.
 716   /// Printf()-like formatting is supported.
 717   void set_err(int no, const char * msg, ...)
 718     __attribute__ ((format (printf, 3, 4)));
 719
 720   /// Set last error info struct.
 721   void set_err(const smart_device::error_info & err)
 722     { m_err = err; }
 723
 724   /// Clear last error info.
 725   void clear_err()
 726     { m_err.clear(); }
 727
 728   /// Set last error number and default message.
 729   /// Message is retrieved from get_msg_for_errno(no).
 730   void set_err(int no);
 731
 732   /// Set last error number and default message to any error_info.
 733   /// Used by set_err(no).
 734   void set_err_var(smart_device::error_info * err, int no);
 735
 736   /// Convert error number into message, used by set_err(no).
 737   /// Default implementation returns strerror(no).
 738   virtual const char * get_msg_for_errno(int no);
 739
 740   ///////////////////////////////////////////////////////////////////////////
 741   // Device factory:
 742
 743   /// Return device object for device 'name' with some 'type'.
 744   /// 'type' is 0 if not specified by user.
 745   /// Return 0 on error.
 746   /// Default implementation selects between ata, scsi and custom device.
 747   virtual smart_device * get_smart_device(const char * name, const char * type);
 748
 749   /// Fill 'devlist' with devices of some 'type' with devices names.
 750   /// specified by some optional 'pattern'.
 751   /// Return false on error.
 752   virtual bool scan_smart_devices(smart_device_list & devlist, const char * type,
 753     const char * pattern = 0) = 0;
 754
 755 protected:
 756   /// Return standard ATA device.
 757   virtual ata_device * get_ata_device(const char * name, const char * type) = 0;
 758
 759   /// Return standard SCSI device.
 760   virtual scsi_device * get_scsi_device(const char * name, const char * type) = 0;
 761
 762   /// Autodetect device if no device type specified.
 763   virtual smart_device * autodetect_smart_device(const char * name) = 0;
 764
 765   /// Return device for platform specific 'type'.
 766   /// Default implementation returns 0.
 767   virtual smart_device * get_custom_smart_device(const char * name, const char * type);
 768
 769   /// Return valid 'type' args accepted by above.
 770   /// This is called in get_valid_dev_types_str().
 771   /// Default implementation returns empty string.
 772   virtual std::string get_valid_custom_dev_types_str();
 773
 774   /// Return ATA->SCSI filter for SAT or USB.
 775   /// Override only if platform needs special handling.
 776   virtual ata_device * get_sat_device(const char * type, scsi_device * scsidev);
 777   //{ implemented in scsiata.cpp }
 778
 779 public:
 780   /// Try to detect a SAT device behind a SCSI interface.
 781   /// Inquiry data can be passed if available.
 782   /// Return appropriate device if yes, otherwise 0.
 783   /// Override only if platform needs special handling.
 784   virtual ata_device * autodetect_sat_device(scsi_device * scsidev,
 785     const unsigned char * inqdata, unsigned inqsize);
 786   //{ implemented in scsiata.cpp }
 787
 788   /// Get type name for USB device with known VENDOR:PRODUCT ID.
 789   /// Return name if device known and supported, otherwise 0.
 790   virtual const char * get_usb_dev_type_by_id(int vendor_id, int product_id,
 791                                               int version = -1);
 792   //{ implemented in scsiata.cpp }
 793
 794 protected:
 795   /// Set interface to use, must be called from init().
 796   static void set(smart_interface * intf)
 797     { s_instance = intf; }
 798
 799 // Implementation
 800 private:
 801   smart_device::error_info m_err;
 802
 803   friend smart_interface * smi(); // below
 804   static smart_interface * s_instance; ///< Pointer to the interface object.
 805
 806   // Prevent copy/assigment
 807   smart_interface(const smart_interface &);
 808   void operator=(const smart_interface &);
 809 };
 810
 811
 812 /////////////////////////////////////////////////////////////////////////////
 813 // smi()
 814
 815 /// Global access to the (usually singleton) smart_interface
 816 inline smart_interface * smi()
 817   { return smart_interface::s_instance; }
 818
 819 /////////////////////////////////////////////////////////////////////////////
 820
 821 #endif // DEV_INTERFACE_H