windows: Deduplicate code and move helper functions to new file win32-helpers.c

Function win32_strerror() was duplicated in two different files:
win32-cfgmgr32.c and win32-kldbg.c. Now there is only one in
win32-helpers.c.

7 files changed, 118 insertions, 132 deletions

diff --git a/lib/Makefile b/lib/Makefile
index a89ac14..4110ad3 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -75,6 +75,10 @@ ifdef PCI_HAVE_PM_WIN32_SYSDBG
 OBJS += win32-sysdbg
 endif
 
+ifdef PCI_OS_WINDOWS
+OBJS += win32-helpers
+endif
+
 all: $(PCILIB) $(PCILIBPC)
 
 ifeq ($(SHARED),no)
@@ -143,9 +147,11 @@ names-hwdb.o: names-hwdb.c $(INCL) names.h
 filter.o: filter.c $(INCL)
 nbsd-libpci.o: nbsd-libpci.c $(INCL)
 hurd.o: hurd.c $(INCL)
-win32-cfgmgr32.o: win32-cfgmgr32.c $(INCL)
-win32-kldbg.o: win32-kldbg.c $(INCL)
-win32-sysdbg.o: win32-sysdbg.c $(INCL)
+win32-helpers.o: win32-helpers.c $(INCL) win32-helpers.h
+win32-cfgmgr32.o: win32-cfgmgr32.c $(INCL) win32-helpers.h
+win32-kldbg.o: win32-kldbg.c $(INCL) win32-helpers.h
+win32-sysdbg.o: win32-sysdbg.c $(INCL) win32-helpers.h
+i386-io-windows.h: win32-helpers.h
 
 # MinGW32 toolchain has some required Win32 header files in /ddk subdirectory.
 # But these header files include another header files from /ddk subdirectory
diff --git a/lib/i386-io-windows.h b/lib/i386-io-windows.h
index fa0db58..69ed821 100644
--- a/lib/i386-io-windows.h
+++ b/lib/i386-io-windows.h
@@ -12,6 +12,7 @@
 
 #include <windows.h>
 #include <aclapi.h>
+#include "win32-helpers.h"
 
 #include "i386-io-access.h"
 
@@ -1276,9 +1277,7 @@ intel_setup_io(struct pci_access *a)
 {
 #ifndef _WIN64
   /* 16/32-bit non-NT systems allow applications to access PCI I/O ports without any special setup. */
-  OSVERSIONINFOA version;
-  version.dwOSVersionInfoSize = sizeof(version);
-  if (GetVersionExA(&version) && version.dwPlatformId < VER_PLATFORM_WIN32_NT)
+  if (win32_is_non_nt_system())
     {
       a->debug("Detected 16/32-bit non-NT system, skipping NT setup...");
       return 1;
@@ -1296,7 +1295,7 @@ intel_setup_io(struct pci_access *a)
   if (!SetProcessUserModeIOPL())
     {
       DWORD error = GetLastError();
-      a->debug("NT ProcessUserModeIOPL call failed: %s.", error == ERROR_INVALID_FUNCTION ? "Not Implemented" : error == ERROR_PRIVILEGE_NOT_HELD ? "Access Denied" : "Operation Failed");
+      a->debug("NT ProcessUserModeIOPL call failed: %s.", error == ERROR_INVALID_FUNCTION ? "Call is not supported" : win32_strerror(error));
       return 0;
     }
 
diff --git a/lib/win32-cfgmgr32.c b/lib/win32-cfgmgr32.c
index 4acac2e..a001187 100644
--- a/lib/win32-cfgmgr32.c
+++ b/lib/win32-cfgmgr32.c
@@ -17,6 +17,7 @@
 #include <wchar.h> /* for wcslen(), wcscpy() */
 
 #include "internal.h"
+#include "win32-helpers.h"
 
 /* Unfortunately MinGW32 toolchain does not provide these cfgmgr32 constants. */
 
@@ -213,32 +214,6 @@ cr_strerror(CONFIGRET cr_error_id)
   return cr_errors[cr_error_id];
 }
 
-static const char *
-win32_strerror(DWORD win32_error_id)
-{
-  /*
-   * Use static buffer which is large enough.
-   * Hopefully no Win32 API error message string is longer than 4 kB.
-   */
-  static char buffer[4096];
-  DWORD len;
-
-  len = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, win32_error_id, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buffer, sizeof(buffer), NULL);
-
-  /* FormatMessage() automatically appends ".\r\n" to the error message. */
-  if (len && buffer[len-1] == '\n')
-    buffer[--len] = '\0';
-  if (len && buffer[len-1] == '\r')
-    buffer[--len] = '\0';
-  if (len && buffer[len-1] == '.')
-    buffer[--len] = '\0';
-
-  if (!len)
-    sprintf(buffer, "Unknown Win32 error %lu", win32_error_id);
-
-  return buffer;
-}
-
 static int
 fmt_validate(const char *s, int len, const char *fmt)
 {
@@ -267,56 +242,6 @@ seq_xdigit_validate(const char *s, int mult, int min)
   return 1;
 }
 
-static BOOL
-is_non_nt_system(void)
-{
-  OSVERSIONINFOA version;
-  version.dwOSVersionInfoSize = sizeof(version);
-  return GetVersionExA(&version) && version.dwPlatformId < VER_PLATFORM_WIN32_NT;
-}
-
-static BOOL
-is_32bit_on_win8_64bit_system(void)
-{
-#ifdef _WIN64
-  return FALSE;
-#else
-  BOOL (WINAPI *MyIsWow64Process)(HANDLE, PBOOL);
-  OSVERSIONINFOA version;
-  HMODULE kernel32;
-  BOOL is_wow64;
-
-  /* Check for Windows 8 (NT 6.2). */
-  version.dwOSVersionInfoSize = sizeof(version);
-  if (!GetVersionExA(&version) ||
-      version.dwPlatformId != VER_PLATFORM_WIN32_NT ||
-      version.dwMajorVersion < 6 ||
-      (version.dwMajorVersion == 6 && version.dwMinorVersion < 2))
-    return FALSE;
-
-  /*
-   * Check for 64-bit system via IsWow64Process() function exported
-   * from 32-bit kernel32.dll library available on the 64-bit systems.
-   * Resolve pointer to this function at runtime as this code path is
-   * primary running on 32-bit systems where are not available 64-bit
-   * functions.
-   */
-
-  kernel32 = GetModuleHandleA("kernel32.dll");
-  if (!kernel32)
-    return FALSE;
-
-  MyIsWow64Process = (void *)GetProcAddress(kernel32, "IsWow64Process");
-  if (!MyIsWow64Process)
-    return FALSE;
-
-  if (!MyIsWow64Process(GetCurrentProcess(), &is_wow64))
-    return FALSE;
-
-  return is_wow64;
-#endif
-}
-
 static LPWSTR
 get_device_service_name(struct pci_access *a, DEVINST devinst, DEVINSTID_A devinst_id, BOOL *supported)
 {
@@ -995,7 +920,7 @@ fill_resources(struct pci_dev *d, DEVINST devinst, DEVINSTID_A devinst_id)
        * application using the hardware resource APIs. For example: An AMD64
        * application for AMD64 systems.
        */
-      if (cr == CR_CALL_NOT_IMPLEMENTED && is_32bit_on_win8_64bit_system())
+      if (cr == CR_CALL_NOT_IMPLEMENTED && win32_is_32bit_on_win8_64bit_system())
         {
           static BOOL warn_once = FALSE;
           if (!warn_once)
@@ -1010,7 +935,7 @@ fill_resources(struct pci_dev *d, DEVINST devinst, DEVINSTID_A devinst_id)
     }
 
   bar_res_count = 0;
-  non_nt_system = is_non_nt_system();
+  non_nt_system = win32_is_non_nt_system();
 
   is_bar_res = TRUE;
   if (non_nt_system)
diff --git a/lib/win32-helpers.c b/lib/win32-helpers.c
new file mode 100644
index 0000000..dd47865
--- /dev/null
+++ b/lib/win32-helpers.c
@@ -0,0 +1,97 @@
+/*
+ *      The PCI Library -- Win32 helper functions
+ *
+ *      Copyright (c) 2023 Pali Rohár <pali@kernel.org>
+ *
+ *      Can be freely distributed and used under the terms of the GNU GPL v2+
+ *
+ *      SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <windows.h>
+#include <stdio.h> /* for sprintf() */
+
+#include "win32-helpers.h"
+
+const char *
+win32_strerror(DWORD win32_error_id)
+{
+  /*
+   * Use static buffer which is large enough.
+   * Hopefully no Win32 API error message string is longer than 4 kB.
+   */
+  static char buffer[4096];
+  DWORD len;
+
+  len = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, win32_error_id, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buffer, sizeof(buffer), NULL);
+
+  /* FormatMessage() automatically appends ".\r\n" to the error message. */
+  if (len && buffer[len-1] == '\n')
+    buffer[--len] = '\0';
+  if (len && buffer[len-1] == '\r')
+    buffer[--len] = '\0';
+  if (len && buffer[len-1] == '.')
+    buffer[--len] = '\0';
+
+  if (!len)
+    sprintf(buffer, "Unknown Win32 error %lu", win32_error_id);
+
+  return buffer;
+}
+
+BOOL
+win32_is_non_nt_system(void)
+{
+  OSVERSIONINFOA version;
+  version.dwOSVersionInfoSize = sizeof(version);
+  return GetVersionExA(&version) && version.dwPlatformId < VER_PLATFORM_WIN32_NT;
+}
+
+BOOL
+win32_is_32bit_on_64bit_system(void)
+{
+  BOOL (WINAPI *MyIsWow64Process)(HANDLE, PBOOL);
+  HMODULE kernel32;
+  BOOL is_wow64;
+
+  /*
+   * Check for 64-bit system via IsWow64Process() function exported
+   * from 32-bit kernel32.dll library available on the 64-bit systems.
+   * Resolve pointer to this function at runtime as this code path is
+   * primary running on 32-bit systems where are not available 64-bit
+   * functions.
+   */
+
+  kernel32 = GetModuleHandle(TEXT("kernel32.dll"));
+  if (!kernel32)
+    return FALSE;
+
+  MyIsWow64Process = (void *)GetProcAddress(kernel32, "IsWow64Process");
+  if (!MyIsWow64Process)
+    return FALSE;
+
+  if (!MyIsWow64Process(GetCurrentProcess(), &is_wow64))
+    return FALSE;
+
+  return is_wow64;
+}
+
+BOOL
+win32_is_32bit_on_win8_64bit_system(void)
+{
+#ifdef _WIN64
+  return FALSE;
+#else
+  OSVERSIONINFOA version;
+
+  /* Check for Windows 8 (NT 6.2). */
+  version.dwOSVersionInfoSize = sizeof(version);
+  if (!GetVersionExA(&version) ||
+      version.dwPlatformId != VER_PLATFORM_WIN32_NT ||
+      version.dwMajorVersion < 6 ||
+      (version.dwMajorVersion == 6 && version.dwMinorVersion < 2))
+    return FALSE;
+
+  return win32_is_32bit_on_64bit_system();
+#endif
+}
diff --git a/lib/win32-helpers.h b/lib/win32-helpers.h
new file mode 100644
index 0000000..18f75de
--- /dev/null
+++ b/lib/win32-helpers.h
@@ -0,0 +1,4 @@
+const char *win32_strerror(DWORD win32_error_id);
+BOOL win32_is_non_nt_system(void);
+BOOL win32_is_32bit_on_64bit_system(void);
+BOOL win32_is_32bit_on_win8_64bit_system(void);
diff --git a/lib/win32-kldbg.c b/lib/win32-kldbg.c
index c051f1a..bb00508 100644
--- a/lib/win32-kldbg.c
+++ b/lib/win32-kldbg.c
@@ -16,6 +16,7 @@
 
 #include "internal.h"
 #include "i386-io-windows.h"
+#include "win32-helpers.h"
 
 #ifndef ERROR_NOT_FOUND
 #define ERROR_NOT_FOUND 1168
@@ -108,53 +109,6 @@ static HANDLE kldbg_dev = INVALID_HANDLE_VALUE;
 static BOOL
 win32_kldbg_pci_bus_data(BOOL WriteBusData, USHORT SegmentNumber, BYTE BusNumber, BYTE DeviceNumber, BYTE FunctionNumber, USHORT Address, PVOID Buffer, ULONG BufferSize, LPDWORD Length);
 
-static const char *
-win32_strerror(DWORD win32_error_id)
-{
-  /*
-   * Use static buffer which is large enough.
-   * Hopefully no Win32 API error message string is longer than 4 kB.
-   */
-  static char buffer[4096];
-  DWORD len;
-
-  len = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, win32_error_id, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buffer, sizeof(buffer), NULL);
-
-  /* FormatMessage() automatically appends ".\r\n" to the error message. */
-  if (len && buffer[len-1] == '\n')
-    buffer[--len] = '\0';
-  if (len && buffer[len-1] == '\r')
-    buffer[--len] = '\0';
-  if (len && buffer[len-1] == '.')
-    buffer[--len] = '\0';
-
-  if (!len)
-    sprintf(buffer, "Unknown Win32 error %lu", win32_error_id);
-
-  return buffer;
-}
-
-static BOOL
-win32_is_32bit_on_64bit_system(void)
-{
-  BOOL (WINAPI *MyIsWow64Process)(HANDLE, PBOOL);
-  HMODULE kernel32;
-  BOOL is_wow64;
-
-  kernel32 = GetModuleHandle(TEXT("kernel32.dll"));
-  if (!kernel32)
-    return FALSE;
-
-  MyIsWow64Process = (void *)GetProcAddress(kernel32, "IsWow64Process");
-  if (!MyIsWow64Process)
-    return FALSE;
-
-  if (!MyIsWow64Process(GetCurrentProcess(), &is_wow64))
-    return FALSE;
-
-  return is_wow64;
-}
-
 static WORD
 win32_get_current_process_machine(void)
 {
diff --git a/lib/win32-sysdbg.c b/lib/win32-sysdbg.c
index 6b17f37..22ecc60 100644
--- a/lib/win32-sysdbg.c
+++ b/lib/win32-sysdbg.c
@@ -12,6 +12,7 @@
 
 #include "internal.h"
 #include "i386-io-windows.h"
+#include "win32-helpers.h"
 
 #ifndef NTSTATUS
 #define NTSTATUS LONG