1 /*
2 * The PCI Library -- Initialization and related things
3 *
4 * Copyright (c) 1997--2024 Martin Mares <[email protected]>
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
get_current_module_handle(void)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
pci_generic_error(char * msg,...)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
pci_generic_warn(char * msg,...)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
pci_generic_debug(char * msg,...)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
pci_null_debug(char * msg UNUSED,...)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 *
pci_malloc(struct pci_access * a,int size)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
pci_mfree(void * x)252 pci_mfree(void *x)
253 {
254 if (x)
255 free(x);
256 }
257
258 char *
pci_strdup(struct pci_access * a,const char * s)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
pci_lookup_method(char * name)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 *
pci_get_method_name(int index)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
pci_init_name_list_path(struct pci_access * a)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
pci_init_name_list_path(struct pci_access * a)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
pci_init_name_list_path(struct pci_access * a)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
pci_init_dns(struct pci_access * a)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 *
pci_alloc(void)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
pci_init_internal(struct pci_access * a,int skip_method)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
pci_init_v35(struct pci_access * a)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 *
pci_clone_access(struct pci_access * a)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
pci_cleanup(struct pci_access * a)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 }
571