dev_interface.h

   1 /*
   2  * dev_interface.h
   3  *
   4  * Home page of code is: http://smartmontools.sourceforge.net
   5  *
   6  * Copyright (C) 2008-12 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 3524 2012-03-21 22:19:31Z chrfranke $\n"
  22
  23 #include "utility.h"
  24
  25 #include <stdexcept>
  26 #include <string>
  27 #include <vector>
  28
  29 /////////////////////////////////////////////////////////////////////////////
  30 // Common functionality for all device types
  31
  32 // Forward declarations
  33 class smart_interface;
  34 class ata_device;
  35 class scsi_device;
  36
  37 /// Base class for all devices
  38 class smart_device
  39 {
  40 // Types
  41 public:
  42   /// Device info strings
  43   struct device_info {
  44     device_info()
  45       { }
  46     device_info(const char * d_name, const char * d_type, const char * r_type)
  47       : dev_name(d_name), info_name(d_name),
  48         dev_type(d_type), req_type(r_type)
  49       { }
  50
  51     std::string dev_name;  ///< Device (path)name
  52     std::string info_name; ///< Informal name
  53     std::string dev_type;  ///< Actual device type
  54     std::string req_type;  ///< Device type requested by user, empty if none
  55   };
  56
  57   /// Error (number,message) pair
  58   struct error_info {
  59     explicit error_info(int n = 0)
  60       : no(n) { }
  61     error_info(int n, const char * m)
  62       : no(n), msg(m) { }
  63     void clear()
  64       { no = 0; msg.erase(); }
  65
  66     int no;          ///< Error number
  67     std::string msg; ///< Error message
  68   };
  69
  70 // Construction
  71 protected:
  72   /// Constructor to init interface and device info.
  73   /// Must be called in implementation classes.
  74   smart_device(smart_interface * intf, const char * dev_name,
  75     const char * dev_type, const char * req_type);
  76
  77   /// Dummy enum for dummy constructor.
  78   enum do_not_use_in_implementation_classes { never_called };
  79   /// Dummy constructor for abstract classes.
  80   /// Must never be called in implementation classes.
  81   smart_device(do_not_use_in_implementation_classes);
  82
  83 public:
  84   virtual ~smart_device() throw();
  85
  86 // Attributes
  87 public:
  88   ///////////////////////////////////////////////
  89   // Dynamic downcasts to actual device flavor
  90
  91   /// Return true if ATA device
  92   bool is_ata() const
  93     { return !!m_ata_ptr; }
  94   /// Return true if SCSI device
  95   bool is_scsi() const
  96     { return !!m_scsi_ptr; }
  97
  98   /// Downcast to ATA device.
  99   ata_device * to_ata()
 100     { return m_ata_ptr; }
 101   /// Downcast to ATA device (const).
 102   const ata_device * to_ata() const
 103     { return m_ata_ptr; }
 104   /// Downcast to SCSI device.
 105   scsi_device * to_scsi()
 106     { return m_scsi_ptr; }
 107   /// Downcast to SCSI device (const).
 108   const scsi_device * to_scsi() const
 109     { return m_scsi_ptr; }
 110
 111   ///////////////////////////////////////////////
 112   // Device information
 113
 114   /// Get device info struct.
 115   const device_info & get_info() const
 116     { return m_info; }
 117
 118   /// Get device (path)name.
 119   const char * get_dev_name() const
 120     { return m_info.dev_name.c_str(); }
 121   /// Get informal name.
 122   const char * get_info_name() const
 123     { return m_info.info_name.c_str(); }
 124   /// Get device type.
 125   const char * get_dev_type() const
 126     { return m_info.dev_type.c_str(); }
 127   /// Get type requested by user, empty if none.
 128   const char * get_req_type() const
 129     { return m_info.req_type.c_str(); }
 130
 131 protected:
 132   /// R/W access to device info struct.
 133   device_info & set_info()
 134     { return m_info; }
 135
 136 public:
 137   ///////////////////////////////////////////////
 138   // Last error information
 139
 140   /// Get last error info struct.
 141   const error_info & get_err() const
 142     { return m_err; }
 143   /// Get last error number.
 144   int get_errno() const
 145     { return m_err.no; }
 146   /// Get last error message.
 147   const char * get_errmsg() const
 148     { return m_err.msg.c_str(); }
 149
 150   /// Set last error number and message.
 151   /// Printf()-like formatting is supported.
 152   /// Returns false always to allow use as a return expression.
 153   bool set_err(int no, const char * msg, ...)
 154     __attribute_format_printf(3, 4);
 155
 156   /// Set last error info struct.
 157   bool set_err(const error_info & err)
 158     { m_err = err; return false; }
 159
 160   /// Clear last error info.
 161   void clear_err()
 162     { m_err.clear(); }
 163
 164   /// Set last error number and default message.
 165   /// Message is retrieved from interface's get_msg_for_errno(no).
 166   bool set_err(int no);
 167
 168 // Operations
 169 public:
 170   ///////////////////////////////////////////////
 171   // Device open/close
 172   // Must be implemented in derived class
 173
 174   /// Return true if device is open.
 175   virtual bool is_open() const = 0;
 176
 177   /// Open device, return false on error.
 178   virtual bool open() = 0;
 179
 180   /// Close device, return false on error.
 181   virtual bool close() = 0;
 182
 183   /// Open device with autodetection support.
 184   /// May return another device for further access.
 185   /// In this case, the original pointer is no longer valid.
 186   /// Default Implementation calls 'open()' and returns 'this'.
 187   virtual smart_device * autodetect_open();
 188
 189   ///////////////////////////////////////////////
 190   // Support for tunnelled devices
 191
 192   /// Return true if other device is owned by this device.
 193   /// Default implementation returns false.
 194   virtual bool owns(const smart_device * dev) const;
 195
 196   /// Release ownership of other device.
 197   /// Default implementation does nothing.
 198   virtual void release(const smart_device * dev);
 199
 200 protected:
 201   /// Get interface which produced this object.
 202   smart_interface * smi()
 203     { return m_intf; }
 204   /// Get interface which produced this object (const).
 205   const smart_interface * smi() const
 206     { return m_intf; }
 207
 208 // Implementation
 209 private:
 210   smart_interface * m_intf;
 211   device_info m_info;
 212   error_info m_err;
 213
 214   // Pointers for to_ata(), to_scsi(),
 215   // set by ATA/SCSI interface classes.
 216   friend class ata_device;
 217   ata_device * m_ata_ptr;
 218   friend class scsi_device;
 219   scsi_device * m_scsi_ptr;
 220
 221   // Prevent copy/assigment
 222   smart_device(const smart_device &);
 223   void operator=(const smart_device &);
 224 };
 225
 226
 227 /////////////////////////////////////////////////////////////////////////////
 228 // ATA specific interface
 229
 230 /// ATA register value and info whether it has ever been set
 231 // (Automatically set by first assignment)
 232 class ata_register
 233 {
 234 public:
 235   ata_register()
 236     : m_val(0x00), m_is_set(false) { }
 237
 238   ata_register & operator=(unsigned char x)
 239     { m_val = x; m_is_set = true; return * this; }
 240
 241   unsigned char val() const
 242     { return m_val; }
 243   operator unsigned char() const
 244     { return m_val; }
 245
 246   bool is_set() const
 247     { return m_is_set; }
 248
 249 private:
 250   unsigned char m_val; ///< Register value
 251   bool m_is_set; ///< true if set
 252 };
 253
 254 /// ATA Input registers (for 28-bit commands)
 255 struct ata_in_regs
 256 {
 257   // ATA-6/7 register names  // ATA-3/4/5        // ATA-8
 258   ata_register features;     // features         // features
 259   ata_register sector_count; // sector count     // count
 260   ata_register lba_low;      // sector number    // ]
 261   ata_register lba_mid;      // cylinder low     // ] lba
 262   ata_register lba_high;     // cylinder high    // ]
 263   ata_register device;       // device/head      // device
 264   ata_register command;      // command          // command
 265
 266   /// Return true if any register is set
 267   bool is_set() const
 268     { return (features.is_set() || sector_count.is_set()
 269       || lba_low.is_set() || lba_mid.is_set() || lba_high.is_set()
 270       || device.is_set() || command.is_set());                    }
 271 };
 272
 273 /// ATA Output registers (for 28-bit commands)
 274 struct ata_out_regs
 275 {
 276   ata_register error;
 277   ata_register sector_count;
 278   ata_register lba_low;
 279   ata_register lba_mid;
 280   ata_register lba_high;
 281   ata_register device;
 282   ata_register status;
 283
 284   /// Return true if any register is set
 285   bool is_set() const
 286     { return (error.is_set() || sector_count.is_set()
 287       || lba_low.is_set() || lba_mid.is_set() || lba_high.is_set()
 288       || device.is_set() || status.is_set());                      }
 289 };
 290
 291
 292 /// 16-bit alias to a 8-bit ATA register pair.
 293 class ata_reg_alias_16
 294 {
 295 public:
 296   ata_reg_alias_16(ata_register & lo, ata_register & hi)
 297     : m_lo(lo), m_hi(hi) { }
 298
 299   ata_reg_alias_16 & operator=(unsigned short x)
 300     { m_lo = (unsigned char) x;
 301       m_hi = (unsigned char)(x >> 8);
 302       return * this;                   }
 303
 304   unsigned short val() const
 305     { return m_lo | (m_hi << 8); }
 306   operator unsigned short() const
 307     { return m_lo | (m_hi << 8); }
 308
 309 private:
 310   ata_register & m_lo, & m_hi;
 311
 312   // References must not be copied.
 313   ata_reg_alias_16(const ata_reg_alias_16 &);
 314   void operator=(const ata_reg_alias_16 &);
 315 };
 316
 317
 318 /// 48-bit alias to six 8-bit ATA registers (for LBA).
 319 class ata_reg_alias_48
 320 {
 321 public:
 322   ata_reg_alias_48(ata_register & ll, ata_register & lm, ata_register & lh,
 323                    ata_register & hl, ata_register & hm, ata_register & hh)
 324     : m_ll(ll), m_lm(lm), m_lh(lh),
 325       m_hl(hl), m_hm(hm), m_hh(hh)
 326     { }
 327
 328   ata_reg_alias_48 & operator=(uint64_t x)
 329     {
 330       m_ll = (unsigned char) x;
 331       m_lm = (unsigned char)(x >>  8);
 332       m_lh = (unsigned char)(x >> 16);
 333       m_hl = (unsigned char)(x >> 24);
 334       m_hm = (unsigned char)(x >> 32);
 335       m_hh = (unsigned char)(x >> 40);
 336       return * this;
 337     }
 338
 339   uint64_t val() const
 340     {
 341       return (   (unsigned)m_ll
 342               | ((unsigned)m_lm <<  8)
 343               | ((unsigned)m_lh << 16)
 344               | ((unsigned)m_hl << 24)
 345               | ((uint64_t)m_hm << 32)
 346               | ((uint64_t)m_hh << 40));
 347     }
 348
 349   operator uint64_t() const
 350     { return val(); }
 351
 352 private:
 353   ata_register & m_ll, & m_lm, & m_lh,
 354                & m_hl, & m_hm, & m_hh;
 355
 356   // References must not be copied.
 357   ata_reg_alias_48(const ata_reg_alias_48 &);
 358   void operator=(const ata_reg_alias_48 &);
 359 };
 360
 361
 362 /// ATA Input registers for 48-bit commands
 363 // See section 4.14 of T13/1532D Volume 1 Revision 4b
 364 //
 365 // Uses ATA-6/7 method to specify 16-bit registers as
 366 // recent (low byte) and previous (high byte) content of
 367 // 8-bit registers.
 368 //
 369 // (ATA-8 ACS does not longer follow this scheme, it uses
 370 // abstract registers with sufficient size and leaves the
 371 // actual mapping to the transport layer.)
 372 //
 373 struct ata_in_regs_48bit
 374 : public ata_in_regs   // "most recently written" registers
 375 {
 376   ata_in_regs prev;  ///< "previous content"
 377
 378   // 16-bit aliases for above pair.
 379   ata_reg_alias_16 features_16;
 380   ata_reg_alias_16 sector_count_16;
 381   ata_reg_alias_16 lba_low_16;
 382   ata_reg_alias_16 lba_mid_16;
 383   ata_reg_alias_16 lba_high_16;
 384
 385   // 48-bit alias to all 8-bit LBA registers.
 386   ata_reg_alias_48 lba_48;
 387
 388   /// Return true if 48-bit command
 389   bool is_48bit_cmd() const
 390     { return prev.is_set(); }
 391
 392   /// Return true if 48-bit command with any nonzero high byte
 393   bool is_real_48bit_cmd() const
 394     { return (   prev.features || prev.sector_count
 395               || prev.lba_low || prev.lba_mid || prev.lba_high); }
 396
 397   ata_in_regs_48bit();
 398 };
 399
 400
 401 /// ATA Output registers for 48-bit commands
 402 struct ata_out_regs_48bit
 403 : public ata_out_regs   // read with HOB=0
 404 {
 405   ata_out_regs prev;  ///< read with HOB=1
 406
 407   // 16-bit aliases for above pair.
 408   ata_reg_alias_16 sector_count_16;
 409   ata_reg_alias_16 lba_low_16;
 410   ata_reg_alias_16 lba_mid_16;
 411   ata_reg_alias_16 lba_high_16;
 412
 413   // 48-bit alias to all 8-bit LBA registers.
 414   ata_reg_alias_48 lba_48;
 415
 416   ata_out_regs_48bit();
 417 };
 418
 419
 420 /// Flags for each ATA output register
 421 struct ata_out_regs_flags
 422 {
 423   bool error, sector_count, lba_low, lba_mid, lba_high, device, status;
 424
 425   /// Return true if any flag is set.
 426   bool is_set() const
 427     { return (   error || sector_count || lba_low
 428               || lba_mid || lba_high || device || status); }
 429
 430   /// Default constructor clears all flags.
 431   ata_out_regs_flags()
 432     : error(false), sector_count(false), lba_low(false), lba_mid(false),
 433       lba_high(false), device(false), status(false) { }
 434 };
 435
 436
 437 /// ATA pass through input parameters
 438 struct ata_cmd_in
 439 {
 440   ata_in_regs_48bit in_regs;  ///< Input registers
 441   ata_out_regs_flags out_needed; ///< True if output register value needed
 442   enum { no_data = 0, data_in, data_out } direction; ///< I/O direction
 443   void * buffer; ///< Pointer to data buffer
 444   unsigned size; ///< Size of buffer
 445
 446   /// Prepare for 28-bit DATA IN command
 447   void set_data_in(void * buf, unsigned nsectors)
 448     {
 449       buffer = buf;
 450       in_regs.sector_count = nsectors;
 451       direction = data_in;
 452       size = nsectors * 512;
 453     }
 454
 455   /// Prepare for 28-bit DATA OUT command
 456   void set_data_out(const void * buf, unsigned nsectors)
 457     {
 458       buffer = const_cast<void *>(buf);
 459       in_regs.sector_count = nsectors;
 460       direction = data_out;
 461       size = nsectors * 512;
 462     }
 463
 464   /// Prepare for 48-bit DATA IN command
 465   void set_data_in_48bit(void * buf, unsigned nsectors)
 466     {
 467       buffer = buf;
 468       // Note: This also sets 'in_regs.is_48bit_cmd()'
 469       in_regs.sector_count_16 = nsectors;
 470       direction = data_in;
 471       size = nsectors * 512;
 472     }
 473
 474   ata_cmd_in();
 475 };
 476
 477 /// ATA pass through output parameters
 478 struct ata_cmd_out
 479 {
 480   ata_out_regs_48bit out_regs; ///< Output registers
 481
 482   ata_cmd_out();
 483 };
 484
 485 /// ATA device access
 486 class ata_device
 487 : virtual public /*extends*/ smart_device
 488 {
 489 public:
 490   /// ATA pass through.
 491   /// Return false on error.
 492   /// Must be implemented in derived class.
 493   virtual bool ata_pass_through(const ata_cmd_in & in, ata_cmd_out & out) = 0;
 494
 495   /// ATA pass through without output registers.
 496   /// Return false on error.
 497   /// Calls ata_pass_through(in, dummy), cannot be reimplemented.
 498   bool ata_pass_through(const ata_cmd_in & in);
 499
 500   /// Return true if OS caches ATA identify sector.
 501   /// Default implementation returns false.
 502   virtual bool ata_identify_is_cached() const;
 503
 504 protected:
 505   /// Check command input parameters.
 506   /// Calls set_err(...) accordingly.
 507   bool ata_cmd_is_ok(const ata_cmd_in & in,
 508     bool data_out_support = false,
 509     bool multi_sector_support = false,
 510     bool ata_48bit_support = false);
 511
 512   /// Hide/unhide ATA interface.
 513   void hide_ata(bool hide = true)
 514     { m_ata_ptr = (!hide ? this : 0); }
 515
 516   /// Default constructor, registers device as ATA.
 517   ata_device()
 518     : smart_device(never_called)
 519     { hide_ata(false); }
 520 };
 521
 522
 523 /////////////////////////////////////////////////////////////////////////////
 524 // SCSI specific interface
 525
 526 struct scsi_cmnd_io;
 527
 528 /// SCSI device access
 529 class scsi_device
 530 : virtual public /*extends*/ smart_device
 531 {
 532 public:
 533   /// SCSI pass through.
 534   /// Returns false on error.
 535   virtual bool scsi_pass_through(scsi_cmnd_io * iop) = 0;
 536
 537 protected:
 538   /// Hide/unhide SCSI interface.
 539   void hide_scsi(bool hide = true)
 540     { m_scsi_ptr = (!hide ? this : 0); }
 541
 542   /// Default constructor, registers device as SCSI.
 543   scsi_device()
 544     : smart_device(never_called)
 545     { hide_scsi(false); }
 546 };
 547
 548
 549 /////////////////////////////////////////////////////////////////////////////
 550 /// Smart pointer class for device pointers
 551
 552 template <class Dev>
 553 class any_device_auto_ptr
 554 {
 555 public:
 556   typedef Dev device_type;
 557
 558   /// Construct from optional pointer to device
 559   /// and optional pointer to base device.
 560   explicit any_device_auto_ptr(device_type * dev = 0,
 561                                smart_device * base_dev = 0)
 562     : m_dev(dev), m_base_dev(base_dev) { }
 563
 564   /// Destructor deletes device object.
 565   ~any_device_auto_ptr() throw()
 566     { reset(); }
 567
 568   /// Assign a new pointer.
 569   /// Throws if a pointer is already assigned.
 570   void operator=(device_type * dev)
 571     {
 572       if (m_dev)
 573         fail();
 574       m_dev = dev;
 575     }
 576
 577   /// Delete device object and clear the pointer.
 578   void reset()
 579     {
 580       if (m_dev) {
 581         if (m_base_dev && m_dev->owns(m_base_dev))
 582           m_dev->release(m_base_dev);
 583         delete m_dev;
 584         m_dev = 0;
 585       }
 586     }
 587
 588   /// Return the pointer and release ownership.
 589   device_type * release()
 590     {
 591       device_type * dev = m_dev;
 592       m_dev = 0;
 593       return dev;
 594     }
 595
 596   /// Replace the pointer.
 597   /// Used to call dev->autodetect_open().
 598   void replace(device_type * dev)
 599     { m_dev = dev; }
 600
 601   /// Return the pointer.
 602   device_type * get() const
 603     { return m_dev; }
 604
 605   /// Pointer dereferencing.
 606   device_type & operator*() const
 607     { return *m_dev; }
 608
 609   /// Pointer dereferencing.
 610   device_type * operator->() const
 611     { return m_dev; }
 612
 613   /// For (ptr != 0) check.
 614   operator bool() const
 615     { return !!m_dev; }
 616
 617   /// For (ptr == 0) check.
 618   bool operator !() const
 619     { return !m_dev; }
 620
 621 private:
 622   device_type * m_dev;
 623   smart_device * m_base_dev;
 624
 625   void fail() const
 626     { throw std::logic_error("any_device_auto_ptr: wrong usage"); }
 627
 628   // Prevent copy/assignment
 629   any_device_auto_ptr(const any_device_auto_ptr<Dev> &);
 630   void operator=(const any_device_auto_ptr<Dev> &);
 631 };
 632
 633 typedef any_device_auto_ptr<smart_device> smart_device_auto_ptr;
 634 typedef any_device_auto_ptr<ata_device>   ata_device_auto_ptr;
 635 typedef any_device_auto_ptr<scsi_device>  scsi_device_auto_ptr;
 636
 637
 638 /////////////////////////////////////////////////////////////////////////////
 639 // smart_device_list
 640
 641 /// List of devices for DEVICESCAN
 642 class smart_device_list
 643 {
 644 // Construction
 645 public:
 646   smart_device_list()
 647     { }
 648
 649   ~smart_device_list() throw()
 650     {
 651       for (unsigned i = 0; i < m_list.size(); i++)
 652         delete m_list[i];
 653     }
 654
 655 // Attributes
 656   unsigned size() const
 657     { return m_list.size(); }
 658
 659 // Operations
 660   void clear()
 661     {
 662       for (unsigned i = 0; i < m_list.size(); i++)
 663         delete m_list[i];
 664       m_list.clear();
 665     }
 666
 667
 668   void push_back(smart_device * dev)
 669     { m_list.push_back(dev); }
 670
 671   void push_back(smart_device_auto_ptr & dev)
 672     {
 673       m_list.push_back(dev.get());
 674       dev.release();
 675     }
 676
 677   smart_device * at(unsigned i)
 678     { return m_list.at(i); }
 679
 680   const smart_device * at(unsigned i) const
 681     { return m_list.at(i); }
 682
 683   smart_device * release(unsigned i)
 684     {
 685       smart_device * dev = m_list.at(i);
 686       m_list[i] = 0;
 687       return dev;
 688     }
 689
 690 // Implementation
 691 private:
 692   std::vector<smart_device *> m_list;
 693
 694   // Prevent copy/assigment
 695   smart_device_list(const smart_device_list &);
 696   void operator=(const smart_device_list &);
 697 };
 698
 699
 700 /////////////////////////////////////////////////////////////////////////////
 701 // smart_interface
 702
 703 /// The platform interface abstraction
 704 class smart_interface
 705 {
 706 public:
 707   /// Initialize platform interface and register with smi().
 708   /// Must be implemented by platform module and register interface with set()
 709   static void init();
 710
 711   smart_interface()
 712     { }
 713
 714   virtual ~smart_interface() throw()
 715     { }
 716
 717   /// Return info string about build host and/or OS version.
 718   /// Default implementation returns SMARTMONTOOLS_BUILD_HOST.
 719   virtual std::string get_os_version_str();
 720
 721   /// Return valid args for device type option/directive.
 722   /// Default implementation returns "ata, scsi, sat, usb*..."
 723   /// concatenated with result from get_valid_custom_dev_types_str().
 724   virtual std::string get_valid_dev_types_str();
 725
 726   /// Return example string for program 'appname'.
 727   /// Default implementation returns empty string.
 728   /// For the migration of print_smartctl_examples(),
 729   /// function is allowed to print examples to stdout.
 730   /// TODO: Remove this hack.
 731   virtual std::string get_app_examples(const char * appname);
 732
 733   /// Get microseconds since some unspecified starting point.
 734   /// Used only for command duration measurements in debug outputs.
 735   /// Returns -1 if unsupported.
 736   /// Default implementation uses clock_gettime(), gettimeofday() or ftime().
 737   virtual int64_t get_timer_usec();
 738
 739   /// Disable/Enable system auto standby/sleep mode.
 740   /// Return false if unsupported or if system is running
 741   /// on battery.
 742   /// Default implementation returns false.
 743   virtual bool disable_system_auto_standby(bool disable);
 744
 745
 746   ///////////////////////////////////////////////
 747   // Last error information
 748
 749   /// Get last error info struct.
 750   const smart_device::error_info & get_err() const
 751     { return m_err; }
 752   /// Get last error number.
 753   int get_errno() const
 754     { return m_err.no; }
 755   /// Get last error message.
 756   const char * get_errmsg() const
 757     { return m_err.msg.c_str(); }
 758
 759   /// Set last error number and message.
 760   /// Printf()-like formatting is supported.
 761   /// Returns false always to allow use as a return expression.
 762   bool set_err(int no, const char * msg, ...)
 763     __attribute_format_printf(3, 4);
 764
 765   /// Set last error info struct.
 766   bool set_err(const smart_device::error_info & err)
 767     { m_err = err; return false; }
 768
 769   /// Clear last error info.
 770   void clear_err()
 771     { m_err.clear(); }
 772
 773   /// Set last error number and default message.
 774   /// Message is retrieved from get_msg_for_errno(no).
 775   bool set_err(int no);
 776
 777   /// Set last error number and default message to any error_info.
 778   /// Used by set_err(no).
 779   bool set_err_var(smart_device::error_info * err, int no);
 780
 781   /// Convert error number into message, used by set_err(no).
 782   /// Default implementation returns strerror(no).
 783   virtual const char * get_msg_for_errno(int no);
 784
 785   ///////////////////////////////////////////////////////////////////////////
 786   // Device factory:
 787
 788   /// Return device object for device 'name' with some 'type'.
 789   /// 'type' is 0 if not specified by user.
 790   /// Return 0 on error.
 791   /// Default implementation selects between ata, scsi and custom device.
 792   virtual smart_device * get_smart_device(const char * name, const char * type);
 793
 794   /// Fill 'devlist' with devices of some 'type' with device names
 795   /// specified by some optional 'pattern'.
 796   /// Return false on error.
 797   virtual bool scan_smart_devices(smart_device_list & devlist, const char * type,
 798     const char * pattern = 0) = 0;
 799
 800 protected:
 801   /// Return standard ATA device.
 802   virtual ata_device * get_ata_device(const char * name, const char * type) = 0;
 803
 804   /// Return standard SCSI device.
 805   virtual scsi_device * get_scsi_device(const char * name, const char * type) = 0;
 806
 807   /// Autodetect device if no device type specified.
 808   virtual smart_device * autodetect_smart_device(const char * name) = 0;
 809
 810   /// Return device for platform specific 'type'.
 811   /// Default implementation returns 0.
 812   virtual smart_device * get_custom_smart_device(const char * name, const char * type);
 813
 814   /// Return valid 'type' args accepted by above.
 815   /// This is called in get_valid_dev_types_str().
 816   /// Default implementation returns empty string.
 817   virtual std::string get_valid_custom_dev_types_str();
 818
 819   /// Return ATA->SCSI filter for SAT or USB.
 820   /// Override only if platform needs special handling.
 821   virtual ata_device * get_sat_device(const char * type, scsi_device * scsidev);
 822   //{ implemented in scsiata.cpp }
 823
 824 public:
 825   /// Try to detect a SAT device behind a SCSI interface.
 826   /// Inquiry data can be passed if available.
 827   /// Return appropriate device if yes, otherwise 0.
 828   /// Override only if platform needs special handling.
 829   virtual ata_device * autodetect_sat_device(scsi_device * scsidev,
 830     const unsigned char * inqdata, unsigned inqsize);
 831   //{ implemented in scsiata.cpp }
 832
 833   /// Get type name for USB device with known VENDOR:PRODUCT ID.
 834   /// Return name if device known and supported, otherwise 0.
 835   virtual const char * get_usb_dev_type_by_id(int vendor_id, int product_id,
 836                                               int version = -1);
 837   //{ implemented in scsiata.cpp }
 838
 839 protected:
 840   /// Set interface to use, must be called from init().
 841   static void set(smart_interface * intf)
 842     { s_instance = intf; }
 843
 844 // Implementation
 845 private:
 846   smart_device::error_info m_err;
 847
 848   friend smart_interface * smi(); // below
 849   static smart_interface * s_instance; ///< Pointer to the interface object.
 850
 851   // Prevent copy/assigment
 852   smart_interface(const smart_interface &);
 853   void operator=(const smart_interface &);
 854 };
 855
 856
 857 /////////////////////////////////////////////////////////////////////////////
 858 // smi()
 859
 860 /// Global access to the (usually singleton) smart_interface
 861 inline smart_interface * smi()
 862   { return smart_interface::s_instance; }
 863
 864 /////////////////////////////////////////////////////////////////////////////
 865
 866 #endif // DEV_INTERFACE_H