X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fwin32_replacements.c;h=26f4b4b7969398ea7c6b81adb696d803703cbcd5;hb=b27e5a1c6b1662eda54ce751b8586fd7d5fb5133;hp=89289b0e056ab708a3696bee00094073c69876db;hpb=a92076249aa233d18ecc378062e654729e27c0d8;p=wimlib

diff --git a/src/win32_replacements.c b/src/win32_replacements.c
index 89289b0e..26f4b4b7 100644
--- a/src/win32_replacements.c
+++ b/src/win32_replacements.c
@@ -4,7 +4,7 @@
  */
 
 /*
- * Copyright (C) 2013 Eric Biggers
+ * Copyright (C) 2013-2016 Eric Biggers
  *
  * This file is free software; you can redistribute it and/or modify it under
  * the terms of the GNU Lesser General Public License as published by the Free
@@ -339,7 +339,7 @@ err:
 
 /* Use the Win32 API to get the number of processors.  */
 unsigned
-win32_get_number_of_processors(void)
+get_available_cpus(void)
 {
 	SYSTEM_INFO sysinfo;
 	GetSystemInfo(&sysinfo);
@@ -348,7 +348,7 @@ win32_get_number_of_processors(void)
 
 /* Use the Win32 API to get the amount of available memory.  */
 u64
-win32_get_avail_memory(void)
+get_available_memory(void)
 {
 	MEMORYSTATUSEX status = {
 		.dwLength = sizeof(status),
@@ -483,51 +483,70 @@ win32_strerror_r_replacement(int errnum, wchar_t *buf, size_t buflen)
 	return 0;
 }
 
+#define MAX_IO_AMOUNT 1048576
+
 static int
 do_pread_or_pwrite(int fd, void *buf, size_t count, off_t offset,
 		   bool is_pwrite)
 {
 	HANDLE h;
 	LARGE_INTEGER orig_offset;
-	DWORD bytes_read_or_written;
+	DWORD result = 0xFFFFFFFF;
 	LARGE_INTEGER relative_offset;
 	OVERLAPPED overlapped;
 	BOOL bret;
+	DWORD err = 0;
 
 	h = (HANDLE)_get_osfhandle(fd);
 	if (h == INVALID_HANDLE_VALUE)
-		goto err;
+		goto error;
 
 	if (GetFileType(h) == FILE_TYPE_PIPE) {
 		errno = ESPIPE;
-		goto err;
+		goto error;
 	}
 
 	/* Get original position */
 	relative_offset.QuadPart = 0;
-	if (!SetFilePointerEx(h, relative_offset, &orig_offset, FILE_CURRENT))
-		goto err_set_errno;
+	if (!SetFilePointerEx(h, relative_offset, &orig_offset, FILE_CURRENT)) {
+		err = GetLastError();
+		win32_error(err, L"Failed to get original file position");
+		goto error;
+	}
 
 	memset(&overlapped, 0, sizeof(overlapped));
 	overlapped.Offset = offset;
 	overlapped.OffsetHigh = offset >> 32;
 
 	/* Do the read or write at the specified offset */
+	count = min(count, MAX_IO_AMOUNT);
+	SetLastError(0);
 	if (is_pwrite)
-		bret = WriteFile(h, buf, count, &bytes_read_or_written, &overlapped);
+		bret = WriteFile(h, buf, count, &result, &overlapped);
 	else
-		bret = ReadFile(h, buf, count, &bytes_read_or_written, &overlapped);
-	if (!bret)
-		goto err_set_errno;
+		bret = ReadFile(h, buf, count, &result, &overlapped);
+	if (!bret) {
+		err = GetLastError();
+		win32_error(err, L"Failed to %s %zu bytes at offset %"PRIu64,
+			    (is_pwrite ? "write" : "read"), count, offset);
+		goto error;
+	}
+
+	wimlib_assert(result <= count);
 
 	/* Restore the original position */
-	if (!SetFilePointerEx(h, orig_offset, NULL, FILE_BEGIN))
-		goto err_set_errno;
+	if (!SetFilePointerEx(h, orig_offset, NULL, FILE_BEGIN)) {
+		err = GetLastError();
+		win32_error(err, L"Failed to restore file position to %"PRIu64,
+			    offset);
+		goto error;
+	}
 
-	return bytes_read_or_written;
-err_set_errno:
-	set_errno_from_GetLastError();
-err:
+	return result;
+
+error:
+	if (err)
+		set_errno_from_win32_error(err);
 	return -1;
 }
 
@@ -535,7 +554,7 @@ err:
  * offset, so it is not safe to use with readers/writers on the same file
  * descriptor.  */
 ssize_t
-pread(int fd, void *buf, size_t count, off_t offset)
+win32_pread(int fd, void *buf, size_t count, off_t offset)
 {
 	return do_pread_or_pwrite(fd, buf, count, offset, false);
 }
@@ -544,11 +563,59 @@ pread(int fd, void *buf, size_t count, off_t offset)
  * offset, so it is not safe to use with readers/writers on the same file
  * descriptor. */
 ssize_t
-pwrite(int fd, const void *buf, size_t count, off_t offset)
+win32_pwrite(int fd, const void *buf, size_t count, off_t offset)
 {
 	return do_pread_or_pwrite(fd, (void*)buf, count, offset, true);
 }
 
+/* Replacement for read() which doesn't hide the Win32 error code */
+ssize_t
+win32_read(int fd, void *buf, size_t count)
+{
+	HANDLE h = (HANDLE)_get_osfhandle(fd);
+	DWORD result = 0xFFFFFFFF;
+
+	if (h == INVALID_HANDLE_VALUE)
+		return -1;
+
+	count = min(count, MAX_IO_AMOUNT);
+	SetLastError(0);
+	if (!ReadFile(h, buf, count, &result, NULL)) {
+		DWORD err = GetLastError();
+		win32_error(err,
+			    L"Error reading %zu bytes from fd %d", count, fd);
+		set_errno_from_win32_error(err);
+		return -1;
+	}
+
+	wimlib_assert(result <= count);
+	return result;
+}
+
+/* Replacement for write() which doesn't hide the Win32 error code */
+ssize_t
+win32_write(int fd, const void *buf, size_t count)
+{
+	HANDLE h = (HANDLE)_get_osfhandle(fd);
+	DWORD result = 0xFFFFFFFF;
+
+	if (h == INVALID_HANDLE_VALUE)
+		return -1;
+
+	count = min(count, MAX_IO_AMOUNT);
+	SetLastError(0);
+	if (!WriteFile(h, buf, count, &result, NULL)) {
+		DWORD err = GetLastError();
+		win32_error(err,
+			    L"Error writing %zu bytes to fd %d", count, fd);
+		set_errno_from_win32_error(err);
+		return -1;
+	}
+
+	wimlib_assert(result <= count);
+	return result;
+}
+
 /* Replacement for glob() in Windows native builds that operates on wide
  * characters.  */
 int