From 2608d8f72d587f5913998e2483c841dc211f9307 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Date: Sun, 26 Dec 2021 19:06:53 +0100
Subject: [PATCH] libpci: For PCI_OS_WINDOWS allows to load pci.ids from
 executable directory

For Windows applications it is common to have all support data files in the
same directory where is stored executable itself, instead of in directory
hardcoded at compile time.

When PCI_PATH_IDS_DIR is set to "." it means that pci.ids file is located
in the current working directory. This is also unsuitable for Windows
command line applications stored in %PATH% because cmd.exe starts in some
default user or system location.

Adds a new option to allow specifying PCI_PATH_IDS_DIR to empty string ""
and for PCI_OS_WINDOWS platform it would mean to locate pci.ids file in the
same directory where is stored currently running executable. On Windows it
is always possible to detected this directory.
---
 lib/configure |  2 +-
 lib/init.c    | 25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/configure b/lib/configure
index 2663b92..40f9ff8 100755
--- a/lib/configure
+++ b/lib/configure
@@ -9,7 +9,7 @@ echo_n() {
 	printf '%s' "$*"
 }
 
-if [ -z "$VERSION" -o -z "$IDSDIR" ] ; then
+if [ -z "$VERSION" ] ; then
 	echo >&2 "Please run the configure script from the top-level Makefile"
 	exit 1
 fi
diff --git a/lib/init.c b/lib/init.c
index 47cdd6f..fa06729 100644
--- a/lib/init.c
+++ b/lib/init.c
@@ -13,6 +13,10 @@
 
 #include "internal.h"
 
+#ifdef PCI_OS_WINDOWS
+#include <windows.h>
+#endif
+
 static struct pci_methods *pci_methods[PCI_ACCESS_MAX] = {
   NULL,
 #ifdef PCI_HAVE_PM_LINUX_SYSFS
@@ -189,7 +193,28 @@ pci_alloc(void)
   int i;
 
   memset(a, 0, sizeof(*a));
+#ifdef PCI_OS_WINDOWS
+  if ((PCI_PATH_IDS_DIR)[0])
+    pci_set_name_list_path(a, PCI_PATH_IDS_DIR "\\" PCI_IDS, 0);
+  else
+    {
+      char *path, *sep;
+      DWORD len;
+
+      path = pci_malloc(a, MAX_PATH+1);
+      len = GetModuleFileNameA(NULL, path, MAX_PATH+1);
+      sep = (len > 0) ? strrchr(path, '\\') : NULL;
+      if (len == 0 || len == MAX_PATH+1 || !sep || MAX_PATH-(size_t)(sep+1-path) < sizeof(PCI_IDS))
+        free(path);
+      else
+        {
+          memcpy(sep+1, PCI_IDS, sizeof(PCI_IDS));
+          pci_set_name_list_path(a, path, 1);
+        }
+    }
+#else
   pci_set_name_list_path(a, PCI_PATH_IDS_DIR "/" PCI_IDS, 0);
+#endif
 #ifdef PCI_USE_DNS
   pci_define_param(a, "net.domain", PCI_ID_DOMAIN, "DNS domain used for resolving of ID's");
   pci_define_param(a, "net.cache_name", "~/.pciids-cache", "Name of the ID cache file");
-- 
2.39.2