lib/init.c

   1 /*
   2  *      The PCI Library -- Initialization and related things
   3  *
   4  *      Copyright (c) 1997--2024 Martin Mares <mj@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL v2+.
   7  *
   8  *      SPDX-License-Identifier: GPL-2.0-or-later
   9  */
  10
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <stdarg.h>
  14 #include <string.h>
  15
  16 #include "internal.h"
  17
  18 #ifdef PCI_OS_DJGPP
  19 #include <crt0.h> /* for __dos_argv0 */
  20 #endif
  21
  22 #ifdef PCI_OS_WINDOWS
  23
  24 #include <windows.h>
  25
  26 /* Force usage of ANSI (char*) variant of GetModuleFileName() function */
  27 #ifdef _WIN32
  28 #ifdef GetModuleFileName
  29 #undef GetModuleFileName
  30 #endif
  31 #define GetModuleFileName GetModuleFileNameA
  32 #endif
  33
  34 /* Define __ImageBase for all linkers */
  35 #ifdef _WIN32
  36 /* GNU LD provides __ImageBase symbol since 2.19, in previous versions it is
  37  * under name _image_base__, so add weak alias for compatibility. */
  38 #ifdef __GNUC__
  39 asm(".weak\t" PCI_STRINGIFY(__MINGW_USYMBOL(__ImageBase)) "\n\t"
  40     ".set\t"  PCI_STRINGIFY(__MINGW_USYMBOL(__ImageBase)) "," PCI_STRINGIFY(__MINGW_USYMBOL(_image_base__)));
  41 #endif
  42 /*
  43  * MSVC link.exe provides __ImageBase symbol since 12.00 (MSVC 6.0), for
  44  * previous versions resolve it at runtime via GetModuleHandleA() which
  45  * returns base for main executable or via VirtualQuery() for DLL builds.
  46  */
  47 #if defined(_MSC_VER) && _MSC_VER < 1200
  48 static HMODULE
  49 get_current_module_handle(void)
  50 {
  51 #ifdef PCI_SHARED_LIB
  52   MEMORY_BASIC_INFORMATION info;
  53   size_t len = VirtualQuery(&get_current_module_handle, &info, sizeof(info));
  54   if (len != sizeof(info))
  55     return NULL;
  56   return (HMODULE)info.AllocationBase;
  57 #else
  58   return GetModuleHandleA(NULL);
  59 #endif
  60 }
  61 #define __ImageBase (*(IMAGE_DOS_HEADER *)get_current_module_handle())
  62 #else
  63 extern IMAGE_DOS_HEADER __ImageBase;
  64 #endif
  65 #endif
  66
  67 #if defined(_WINDLL)
  68 extern HINSTANCE _hModule;
  69 #elif defined(_WINDOWS)
  70 extern HINSTANCE _hInstance;
  71 #endif
  72
  73 #endif
  74
  75 static struct pci_methods *pci_methods[PCI_ACCESS_MAX] = {
  76   NULL,
  77 #ifdef PCI_HAVE_PM_LINUX_SYSFS
  78   &pm_linux_sysfs,
  79 #else
  80   NULL,
  81 #endif
  82 #ifdef PCI_HAVE_PM_LINUX_PROC
  83   &pm_linux_proc,
  84 #else
  85   NULL,
  86 #endif
  87 #ifdef PCI_HAVE_PM_INTEL_CONF
  88   &pm_intel_conf1,
  89   &pm_intel_conf2,
  90 #else
  91   NULL,
  92   NULL,
  93 #endif
  94 #ifdef PCI_HAVE_PM_FBSD_DEVICE
  95   &pm_fbsd_device,
  96 #else
  97   NULL,
  98 #endif
  99 #ifdef PCI_HAVE_PM_AIX_DEVICE
 100   &pm_aix_device,
 101 #else
 102   NULL,
 103 #endif
 104 #ifdef PCI_HAVE_PM_NBSD_LIBPCI
 105   &pm_nbsd_libpci,
 106 #else
 107   NULL,
 108 #endif
 109 #ifdef PCI_HAVE_PM_OBSD_DEVICE
 110   &pm_obsd_device,
 111 #else
 112   NULL,
 113 #endif
 114 #ifdef PCI_HAVE_PM_DUMP
 115   &pm_dump,
 116 #else
 117   NULL,
 118 #endif
 119 #ifdef PCI_HAVE_PM_DARWIN_DEVICE
 120   &pm_darwin,
 121 #else
 122   NULL,
 123 #endif
 124 #ifdef PCI_HAVE_PM_SYLIXOS_DEVICE
 125   &pm_sylixos_device,
 126 #else
 127   NULL,
 128 #endif
 129 #ifdef PCI_HAVE_PM_HURD_CONF
 130   &pm_hurd,
 131 #else
 132   NULL,
 133 #endif
 134 #ifdef PCI_HAVE_PM_WIN32_CFGMGR32
 135   &pm_win32_cfgmgr32,
 136 #else
 137   NULL,
 138 #endif
 139 #ifdef PCI_HAVE_PM_WIN32_KLDBG
 140   &pm_win32_kldbg,
 141 #else
 142   NULL,
 143 #endif
 144 #ifdef PCI_HAVE_PM_WIN32_SYSDBG
 145   &pm_win32_sysdbg,
 146 #else
 147   NULL,
 148 #endif
 149 #ifdef PCI_HAVE_PM_MMIO_CONF
 150   &pm_mmio_conf1,
 151   &pm_mmio_conf1_ext,
 152 #else
 153   NULL,
 154   NULL,
 155 #endif
 156 #if defined(PCI_HAVE_PM_ECAM)
 157   &pm_ecam,
 158 #else
 159   NULL,
 160 #endif
 161 #if defined(PCI_HAVE_PM_AOS_EXPANSION)
 162   &pm_aos_expansion,
 163 #else
 164   NULL,
 165 #endif
 166 #ifdef PCI_HAVE_PM_RT_THREAD_SMART_DM
 167   &pm_rt_thread_smart_dm,
 168 #else
 169   NULL,
 170 #endif
 171 };
 172
 173 // If PCI_ACCESS_AUTO is selected, we probe the access methods in this order
 174 static int probe_sequence[] = {
 175   // System-specific methods
 176   PCI_ACCESS_SYS_BUS_PCI,
 177   PCI_ACCESS_PROC_BUS_PCI,
 178   PCI_ACCESS_FBSD_DEVICE,
 179   PCI_ACCESS_AIX_DEVICE,
 180   PCI_ACCESS_NBSD_LIBPCI,
 181   PCI_ACCESS_OBSD_DEVICE,
 182   PCI_ACCESS_DARWIN,
 183   PCI_ACCESS_SYLIXOS_DEVICE,
 184   PCI_ACCESS_HURD,
 185   PCI_ACCESS_WIN32_CFGMGR32,
 186   PCI_ACCESS_WIN32_KLDBG,
 187   PCI_ACCESS_WIN32_SYSDBG,
 188   PCI_ACCESS_AOS_EXPANSION,
 189   PCI_ACCESS_RT_THREAD_SMART_DM,
 190   // Low-level methods poking the hardware directly
 191   PCI_ACCESS_ECAM,
 192   PCI_ACCESS_I386_TYPE1,
 193   PCI_ACCESS_I386_TYPE2,
 194   PCI_ACCESS_MMIO_TYPE1_EXT,
 195   PCI_ACCESS_MMIO_TYPE1,
 196   -1,
 197 };
 198
 199 static void PCI_NONRET
 200 pci_generic_error(char *msg, ...)
 201 {
 202   va_list args;
 203
 204   va_start(args, msg);
 205   fputs("pcilib: ", stderr);
 206   vfprintf(stderr, msg, args);
 207   va_end(args);
 208   fputc('\n', stderr);
 209   exit(1);
 210 }
 211
 212 static void
 213 pci_generic_warn(char *msg, ...)
 214 {
 215   va_list args;
 216
 217   va_start(args, msg);
 218   fputs("pcilib: ", stderr);
 219   vfprintf(stderr, msg, args);
 220   va_end(args);
 221   fputc('\n', stderr);
 222 }
 223
 224 static void
 225 pci_generic_debug(char *msg, ...)
 226 {
 227   va_list args;
 228
 229   va_start(args, msg);
 230   vfprintf(stdout, msg, args);
 231   va_end(args);
 232 }
 233
 234 static void
 235 pci_null_debug(char *msg UNUSED, ...)
 236 {
 237 }
 238
 239 // Memory allocation functions are safe to call if pci_access is not fully initalized or even NULL
 240
 241 void *
 242 pci_malloc(struct pci_access *a, int size)
 243 {
 244   void *x = malloc(size);
 245
 246   if (!x)
 247     (a && a->error ? a->error : pci_generic_error)("Out of memory (allocation of %d bytes failed)", size);
 248   return x;
 249 }
 250
 251 void
 252 pci_mfree(void *x)
 253 {
 254   if (x)
 255     free(x);
 256 }
 257
 258 char *
 259 pci_strdup(struct pci_access *a, const char *s)
 260 {
 261   int len = strlen(s) + 1;
 262   char *t = pci_malloc(a, len);
 263   memcpy(t, s, len);
 264   return t;
 265 }
 266
 267 int
 268 pci_lookup_method(char *name)
 269 {
 270   int i;
 271
 272   for (i=0; i<PCI_ACCESS_MAX; i++)
 273     if (pci_methods[i] && !strcmp(pci_methods[i]->name, name))
 274       return i;
 275   return -1;
 276 }
 277
 278 char *
 279 pci_get_method_name(int index)
 280 {
 281   if (index < 0 || index >= PCI_ACCESS_MAX)
 282     return NULL;
 283   else if (!pci_methods[index])
 284     return "";
 285   else
 286     return pci_methods[index]->name;
 287 }
 288
 289 #if defined(PCI_OS_WINDOWS) || defined(PCI_OS_DJGPP)
 290
 291 static void
 292 pci_init_name_list_path(struct pci_access *a)
 293 {
 294   if ((PCI_PATH_IDS_DIR)[0])
 295     pci_set_name_list_path(a, PCI_PATH_IDS_DIR "\\" PCI_IDS, 0);
 296   else
 297     {
 298       char *path, *sep;
 299       size_t len;
 300
 301 #if defined(PCI_OS_WINDOWS) && (defined(_WIN32) || defined(_WINDLL) || defined(_WINDOWS))
 302
 303       HMODULE module;
 304       size_t size;
 305
 306 #if defined(_WIN32)
 307       module = (HINSTANCE)&__ImageBase;
 308 #elif defined(_WINDLL)
 309       module = _hModule;
 310 #elif defined(_WINDOWS)
 311       module = _hInstance;
 312 #endif
 313
 314       /*
 315        * Module file name can have arbitrary length despite all MS examples say
 316        * about MAX_PATH upper limit. This limit does not apply for example when
 317        * executable is running from network disk with very long UNC paths or
 318        * when using "\\??\\" prefix for specifying executable binary path.
 319        * Function GetModuleFileName() returns passed size argument when passed
 320        * buffer is too small and does not signal any error. In this case retry
 321        * again with larger buffer.
 322        */
 323       size = 256; /* initial buffer size (more than sizeof(PCI_IDS)-4) */
 324 retry:
 325       path = pci_malloc(a, size);
 326       len = GetModuleFileName(module, path, size-sizeof(PCI_IDS)-4); /* 4 for "\\\\?\\" */
 327       if (len >= size-sizeof(PCI_IDS)-4)
 328         {
 329           free(path);
 330           size *= 2;
 331           goto retry;
 332         }
 333       else if (len == 0)
 334         path[0] = '\0';
 335
 336       /*
 337        * GetModuleFileName() has bugs. On Windows 10 it prepends current drive
 338        * letter if path is just pure NT namespace (with "\\??\\" prefix). Such
 339        * extra drive letter makes path fully invalid and unusable. So remove
 340        * extra drive letter to make path valid again.
 341        * Reproduce: CreateProcessW("\\??\\C:\\lspci.exe", ...)
 342        */
 343       if (((path[0] >= 'a' && path[0] <= 'z') ||
 344            (path[0] >= 'A' && path[0] <= 'Z')) &&
 345           strncmp(path+1, ":\\??\\", 5) == 0)
 346         {
 347           memmove(path, path+2, len-2);
 348           len -= 2;
 349           path[len] = '\0';
 350         }
 351
 352       /*
 353        * GetModuleFileName() has bugs. On Windows 10 it does not add "\\\\?\\"
 354        * prefix when path is in native NT UNC namespace. Such path is treated by
 355        * WinAPI/DOS functions as standard DOS path relative to the current
 356        * directory, hence something completely different. So prepend missing
 357        * "\\\\?\\" prefix to make path valid again.
 358        * Reproduce: CreateProcessW("\\??\\UNC\\10.0.2.4\\qemu\\lspci.exe", ...)
 359        *
 360        * If path starts with DOS drive letter and with appended PCI_IDS is
 361        * longer than 260 bytes and is without "\\\\?\\" prefix then append it.
 362        * This prefix is required for paths and file names with DOS drive letter
 363        * longer than 260 bytes.
 364        */
 365       if (strncmp(path, "\\UNC\\", 5) == 0 ||
 366           strncmp(path, "UNC\\", 4) == 0 ||
 367           (((path[0] >= 'a' && path[0] <= 'z') || (path[0] >= 'A' && path[0] <= 'Z')) &&
 368            len + sizeof(PCI_IDS) >= 260))
 369         {
 370           memmove(path+4, path, len);
 371           memcpy(path, "\\\\?\\", 4);
 372           len += 4;
 373           path[len] = '\0';
 374         }
 375
 376 #elif defined(PCI_OS_DJGPP) || defined(PCI_OS_WINDOWS)
 377
 378       const char *exe_path;
 379
 380 #ifdef PCI_OS_DJGPP
 381       exe_path = __dos_argv0;
 382 #else
 383       exe_path = _pgmptr;
 384 #endif
 385
 386       len = strlen(exe_path);
 387       path = pci_malloc(a, len+sizeof(PCI_IDS));
 388       memcpy(path, exe_path, len+1);
 389
 390 #endif
 391
 392       sep = strrchr(path, '\\');
 393       if (!sep)
 394         {
 395           /*
 396            * If current module path (current executable for static builds or
 397            * current DLL library for shared build) cannot be determined then
 398            * fallback to the current directory.
 399            */
 400           free(path);
 401           pci_set_name_list_path(a, PCI_IDS, 0);
 402         }
 403       else
 404         {
 405           memcpy(sep+1, PCI_IDS, sizeof(PCI_IDS));
 406           pci_set_name_list_path(a, path, 1);
 407         }
 408     }
 409 }
 410
 411 #elif defined PCI_OS_AMIGAOS
 412
 413 static void
 414 pci_init_name_list_path(struct pci_access *a)
 415 {
 416   int len = strlen(PCI_PATH_IDS_DIR);
 417
 418   if (!len)
 419     pci_set_name_list_path(a, PCI_IDS, 0);
 420   else
 421     {
 422       char last_char = PCI_PATH_IDS_DIR[len - 1];
 423       if (last_char == ':' || last_char == '/')  // root or parent char
 424         pci_set_name_list_path(a, PCI_PATH_IDS_DIR PCI_IDS, 0);
 425       else
 426         pci_set_name_list_path(a, PCI_PATH_IDS_DIR "/" PCI_IDS, 0);
 427     }
 428 }
 429
 430 #else
 431
 432 static void
 433 pci_init_name_list_path(struct pci_access *a)
 434 {
 435   pci_set_name_list_path(a, PCI_PATH_IDS_DIR "/" PCI_IDS, 0);
 436 }
 437
 438 #endif
 439
 440 #ifdef PCI_USE_DNS
 441
 442 static void
 443 pci_init_dns(struct pci_access *a)
 444 {
 445   pci_define_param(a, "net.domain", PCI_ID_DOMAIN, "DNS domain used for resolving of ID's");
 446   a->id_lookup_mode = PCI_LOOKUP_CACHE;
 447
 448   char *cache_dir = getenv("XDG_CACHE_HOME");
 449   if (!cache_dir)
 450     cache_dir = "~/.cache";
 451
 452   int name_len = strlen(cache_dir) + 32;
 453   char *cache_name = pci_malloc(NULL, name_len);
 454   snprintf(cache_name, name_len, "%s/pci-ids", cache_dir);
 455   struct pci_param *param = pci_define_param(a, "net.cache_name", cache_name, "Name of the ID cache file");
 456   param->value_malloced = 1;
 457 }
 458
 459 #endif
 460
 461 struct pci_access *
 462 pci_alloc(void)
 463 {
 464   struct pci_access *a = pci_malloc(NULL, sizeof(struct pci_access));
 465   int i;
 466
 467   memset(a, 0, sizeof(*a));
 468   pci_init_name_list_path(a);
 469 #ifdef PCI_USE_DNS
 470   pci_init_dns(a);
 471 #endif
 472 #ifdef PCI_HAVE_HWDB
 473   pci_define_param(a, "hwdb.disable", "0", "Do not look up names in UDEV's HWDB if non-zero");
 474 #endif
 475   for (i=0; i<PCI_ACCESS_MAX; i++)
 476     if (pci_methods[i] && pci_methods[i]->config)
 477       pci_methods[i]->config(a);
 478   return a;
 479 }
 480
 481 int
 482 pci_init_internal(struct pci_access *a, int skip_method)
 483 {
 484   if (!a->error)
 485     a->error = pci_generic_error;
 486   if (!a->warning)
 487     a->warning = pci_generic_warn;
 488   if (!a->debug)
 489     a->debug = pci_generic_debug;
 490   if (!a->debugging)
 491     a->debug = pci_null_debug;
 492
 493   if (a->method != PCI_ACCESS_AUTO)
 494     {
 495       if (a->method >= PCI_ACCESS_MAX || !pci_methods[a->method])
 496         a->error("This access method is not supported.");
 497       a->methods = pci_methods[a->method];
 498     }
 499   else
 500     {
 501       unsigned int i;
 502       for (i=0; probe_sequence[i] >= 0; i++)
 503         {
 504           struct pci_methods *m = pci_methods[probe_sequence[i]];
 505           if (!m)
 506             continue;
 507           if (skip_method == probe_sequence[i])
 508             continue;
 509           a->debug("Trying method %s...", m->name);
 510           if (m->detect(a))
 511             {
 512               a->debug("...OK\n");
 513               a->methods = m;
 514               a->method = probe_sequence[i];
 515               break;
 516             }
 517           a->debug("...No.\n");
 518         }
 519       if (!a->methods)
 520         return 0;
 521     }
 522   a->debug("Decided to use %s\n", a->methods->name);
 523   a->methods->init(a);
 524   return 1;
 525 }
 526
 527 void
 528 pci_init_v35(struct pci_access *a)
 529 {
 530   if (!pci_init_internal(a, -1))
 531     a->error("Cannot find any working access method.");
 532 }
 533
 534 STATIC_ALIAS(void pci_init(struct pci_access *a), pci_init_v35(a));
 535 DEFINE_ALIAS(void pci_init_v30(struct pci_access *a), pci_init_v35);
 536 SYMBOL_VERSION(pci_init_v30, pci_init@LIBPCI_3.0);
 537 SYMBOL_VERSION(pci_init_v35, pci_init@@LIBPCI_3.5);
 538
 539 struct pci_access *
 540 pci_clone_access(struct pci_access *a)
 541 {
 542   struct pci_access *b = pci_alloc();
 543
 544   b->writeable = a->writeable;
 545   b->buscentric = a->buscentric;
 546   b->debugging = a->debugging;
 547   b->error = a->error;
 548   b->warning = a->warning;
 549   b->debug = a->debug;
 550
 551   return b;
 552 }
 553
 554 void
 555 pci_cleanup(struct pci_access *a)
 556 {
 557   struct pci_dev *d, *e;
 558
 559   for (d=a->devices; d; d=e)
 560     {
 561       e = d->next;
 562       pci_free_dev(d);
 563     }
 564   if (a->methods)
 565     a->methods->cleanup(a);
 566   pci_free_name_list(a);
 567   pci_free_params(a);
 568   pci_set_name_list_path(a, NULL, 0);
 569   pci_mfree(a);
 570 }