diff --git a/7.4.851 b/7.4.851
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+To: vim_dev@googlegroups.com
+Subject: Patch 7.4.851
+Fcc: outbox
+From: Bram Moolenaar <Bram@moolenaar.net>
+Mime-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+------------
+
+Patch 7.4.851
+Problem: Saving and restoring the console buffer does not work properly.
+Solution: Instead of ReadConsoleOutputA/WriteConsoleOutputA use
+ CreateConsoleScreenBuffer and SetConsoleActiveScreenBuffer.
+ (Ken Takata)
+Files: src/os_win32.c
+
+
+*** ../vim-7.4.850/src/os_win32.c 2015-08-04 19:26:59.747310733 +0200
+--- src/os_win32.c 2015-09-01 20:03:57.428750713 +0200
+***************
+*** 2192,2199 ****
+ {
+ BOOL IsValid;
+ CONSOLE_SCREEN_BUFFER_INFO Info;
+! PCHAR_INFO Buffer;
+! COORD BufferSize;
+ } ConsoleBuffer;
+
+ /*
+--- 2192,2198 ----
+ {
+ BOOL IsValid;
+ CONSOLE_SCREEN_BUFFER_INFO Info;
+! HANDLE handle;
+ } ConsoleBuffer;
+
+ /*
+***************
+*** 2210,2286 ****
+ SaveConsoleBuffer(
+ ConsoleBuffer *cb)
+ {
+- DWORD NumCells;
+- COORD BufferCoord;
+- SMALL_RECT ReadRegion;
+- WORD Y, Y_incr;
+-
+ if (cb == NULL)
+ return FALSE;
+
+! if (!GetConsoleScreenBufferInfo(g_hConOut, &cb->Info))
+ {
+ cb->IsValid = FALSE;
+ return FALSE;
+ }
+ cb->IsValid = TRUE;
+
+! /*
+! * Allocate a buffer large enough to hold the entire console screen
+! * buffer. If this ConsoleBuffer structure has already been initialized
+! * with a buffer of the correct size, then just use that one.
+! */
+! if (!cb->IsValid || cb->Buffer == NULL ||
+! cb->BufferSize.X != cb->Info.dwSize.X ||
+! cb->BufferSize.Y != cb->Info.dwSize.Y)
+! {
+! cb->BufferSize.X = cb->Info.dwSize.X;
+! cb->BufferSize.Y = cb->Info.dwSize.Y;
+! NumCells = cb->BufferSize.X * cb->BufferSize.Y;
+! vim_free(cb->Buffer);
+! cb->Buffer = (PCHAR_INFO)alloc(NumCells * sizeof(CHAR_INFO));
+! if (cb->Buffer == NULL)
+! return FALSE;
+! }
+
+ /*
+! * We will now copy the console screen buffer into our buffer.
+! * ReadConsoleOutput() seems to be limited as far as how much you
+! * can read at a time. Empirically, this number seems to be about
+! * 12000 cells (rows * columns). Start at position (0, 0) and copy
+! * in chunks until it is all copied. The chunks will all have the
+! * same horizontal characteristics, so initialize them now. The
+! * height of each chunk will be (12000 / width).
+ */
+! BufferCoord.X = 0;
+ ReadRegion.Left = 0;
+! ReadRegion.Right = cb->Info.dwSize.X - 1;
+! Y_incr = 12000 / cb->Info.dwSize.X;
+! for (Y = 0; Y < cb->BufferSize.Y; Y += Y_incr)
+ {
+! /*
+! * Read into position (0, Y) in our buffer.
+! */
+! BufferCoord.Y = Y;
+! /*
+! * Read the region whose top left corner is (0, Y) and whose bottom
+! * right corner is (width - 1, Y + Y_incr - 1). This should define
+! * a region of size width by Y_incr. Don't worry if this region is
+! * too large for the remaining buffer; it will be cropped.
+! */
+! ReadRegion.Top = Y;
+! ReadRegion.Bottom = Y + Y_incr - 1;
+! if (!ReadConsoleOutput(g_hConOut, /* output handle */
+! cb->Buffer, /* our buffer */
+! cb->BufferSize, /* dimensions of our buffer */
+! BufferCoord, /* offset in our buffer */
+! &ReadRegion)) /* region to save */
+! {
+! vim_free(cb->Buffer);
+! cb->Buffer = NULL;
+! return FALSE;
+! }
+ }
+
+ return TRUE;
+ }
+--- 2209,2289 ----
+ SaveConsoleBuffer(
+ ConsoleBuffer *cb)
+ {
+ if (cb == NULL)
+ return FALSE;
+
+! if (!GetConsoleScreenBufferInfo(cb->handle, &cb->Info))
+ {
+ cb->IsValid = FALSE;
+ return FALSE;
+ }
+ cb->IsValid = TRUE;
+
+! return TRUE;
+! }
+!
+! /*
+! * CopyOldConsoleBuffer()
+! * Description:
+! * Copies the old console buffer contents to the current console buffer.
+! * This is used when 'restorescreen' is off.
+! * Returns:
+! * TRUE on success
+! */
+! static BOOL
+! CopyOldConsoleBuffer(
+! ConsoleBuffer *cb,
+! HANDLE hConOld)
+! {
+! COORD BufferCoord;
+! COORD BufferSize;
+! PCHAR_INFO Buffer;
+! DWORD NumCells;
+! SMALL_RECT ReadRegion;
+
+ /*
+! * Before copying the buffer contents, clear the current buffer, and
+! * restore the window information. Doing this now prevents old buffer
+! * contents from "flashing" onto the screen.
+ */
+! ClearConsoleBuffer(cb->Info.wAttributes);
+!
+! /* We only need to copy the window area, not whole buffer. */
+! BufferSize.X = cb->Info.srWindow.Right - cb->Info.srWindow.Left + 1;
+! BufferSize.Y = cb->Info.srWindow.Bottom - cb->Info.srWindow.Top + 1;
+ ReadRegion.Left = 0;
+! ReadRegion.Right = BufferSize.X - 1;
+! ReadRegion.Top = 0;
+! ReadRegion.Bottom = BufferSize.Y - 1;
+!
+! NumCells = BufferSize.X * BufferSize.Y;
+! Buffer = (PCHAR_INFO)alloc(NumCells * sizeof(CHAR_INFO));
+! if (Buffer == NULL)
+! return FALSE;
+!
+! BufferCoord.X = 0;
+! BufferCoord.Y = 0;
+!
+! if (!ReadConsoleOutputW(hConOld, /* output handle */
+! Buffer, /* our buffer */
+! BufferSize, /* dimensions of our buffer */
+! BufferCoord, /* offset in our buffer */
+! &ReadRegion)) /* region to save */
+ {
+! vim_free(Buffer);
+! return FALSE;
+! }
+! if (!WriteConsoleOutputW(g_hConOut, /* output handle */
+! Buffer, /* our buffer */
+! BufferSize, /* dimensions of our buffer */
+! BufferCoord, /* offset in our buffer */
+! &ReadRegion)) /* region to restore */
+! {
+! vim_free(Buffer);
+! return FALSE;
+ }
++ vim_free(Buffer);
++ SetConsoleWindowInfo(g_hConOut, TRUE, &ReadRegion);
+
+ return TRUE;
+ }
+***************
+*** 2299,2365 ****
+ ConsoleBuffer *cb,
+ BOOL RestoreScreen)
+ {
+! COORD BufferCoord;
+! SMALL_RECT WriteRegion;
+
+ if (cb == NULL || !cb->IsValid)
+ return FALSE;
+
+! /*
+! * Before restoring the buffer contents, clear the current buffer, and
+! * restore the cursor position and window information. Doing this now
+! * prevents old buffer contents from "flashing" onto the screen.
+! */
+! if (RestoreScreen)
+! ClearConsoleBuffer(cb->Info.wAttributes);
+!
+! FitConsoleWindow(cb->Info.dwSize, TRUE);
+! if (!SetConsoleScreenBufferSize(g_hConOut, cb->Info.dwSize))
+! return FALSE;
+! if (!SetConsoleTextAttribute(g_hConOut, cb->Info.wAttributes))
+! return FALSE;
+!
+! if (!RestoreScreen)
+! {
+! /*
+! * No need to restore the screen buffer contents, so we're done.
+! */
+! return TRUE;
+! }
+!
+! if (!SetConsoleCursorPosition(g_hConOut, cb->Info.dwCursorPosition))
+! return FALSE;
+! if (!SetConsoleWindowInfo(g_hConOut, TRUE, &cb->Info.srWindow))
+! return FALSE;
+!
+! /*
+! * Restore the screen buffer contents.
+! */
+! if (cb->Buffer != NULL)
+! {
+! BufferCoord.X = 0;
+! BufferCoord.Y = 0;
+! WriteRegion.Left = 0;
+! WriteRegion.Top = 0;
+! WriteRegion.Right = cb->Info.dwSize.X - 1;
+! WriteRegion.Bottom = cb->Info.dwSize.Y - 1;
+! if (!WriteConsoleOutput(g_hConOut, /* output handle */
+! cb->Buffer, /* our buffer */
+! cb->BufferSize, /* dimensions of our buffer */
+! BufferCoord, /* offset in our buffer */
+! &WriteRegion)) /* region to restore */
+! {
+! return FALSE;
+! }
+! }
+
+ return TRUE;
+ }
+
+- #define FEAT_RESTORE_ORIG_SCREEN
+- #ifdef FEAT_RESTORE_ORIG_SCREEN
+- static ConsoleBuffer g_cbOrig = { 0 };
+- #endif
+ static ConsoleBuffer g_cbNonTermcap = { 0 };
+ static ConsoleBuffer g_cbTermcap = { 0 };
+
+--- 2302,2321 ----
+ ConsoleBuffer *cb,
+ BOOL RestoreScreen)
+ {
+! HANDLE hConOld;
+
+ if (cb == NULL || !cb->IsValid)
+ return FALSE;
+
+! hConOld = g_hConOut;
+! g_hConOut = cb->handle;
+! if (!RestoreScreen && exiting)
+! CopyOldConsoleBuffer(cb, hConOld);
+! SetConsoleActiveScreenBuffer(g_hConOut);
+
+ return TRUE;
+ }
+
+ static ConsoleBuffer g_cbNonTermcap = { 0 };
+ static ConsoleBuffer g_cbTermcap = { 0 };
+
+***************
+*** 2498,2506 ****
+ void
+ mch_init(void)
+ {
+- #ifndef FEAT_RESTORE_ORIG_SCREEN
+- CONSOLE_SCREEN_BUFFER_INFO csbi;
+- #endif
+ #ifndef __MINGW32__
+ extern int _fmode;
+ #endif
+--- 2454,2459 ----
+***************
+*** 2521,2536 ****
+ else
+ create_conin();
+ g_hConOut = GetStdHandle(STD_OUTPUT_HANDLE);
+
+- #ifdef FEAT_RESTORE_ORIG_SCREEN
+- /* Save the initial console buffer for later restoration */
+- SaveConsoleBuffer(&g_cbOrig);
+- g_attrCurrent = g_attrDefault = g_cbOrig.Info.wAttributes;
+- #else
+ /* Get current text attributes */
+! GetConsoleScreenBufferInfo(g_hConOut, &csbi);
+! g_attrCurrent = g_attrDefault = csbi.wAttributes;
+! #endif
+ if (cterm_normal_fg_color == 0)
+ cterm_normal_fg_color = (g_attrCurrent & 0xf) + 1;
+ if (cterm_normal_bg_color == 0)
+--- 2474,2487 ----
+ else
+ create_conin();
+ g_hConOut = GetStdHandle(STD_OUTPUT_HANDLE);
++ g_cbNonTermcap.handle = g_hConOut;
++ g_cbTermcap.handle = CreateConsoleScreenBuffer(
++ GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE,
++ NULL, CONSOLE_TEXTMODE_BUFFER, NULL);
+
+ /* Get current text attributes */
+! SaveConsoleBuffer(&g_cbNonTermcap);
+! g_attrCurrent = g_attrDefault = g_cbNonTermcap.Info.wAttributes;
+ if (cterm_normal_fg_color == 0)
+ cterm_normal_fg_color = (g_attrCurrent & 0xf) + 1;
+ if (cterm_normal_bg_color == 0)
+***************
+*** 2630,2635 ****
+--- 2581,2588 ----
+ SetConsoleMode(g_hConIn, g_cmodein);
+ SetConsoleMode(g_hConOut, g_cmodeout);
+
++ CloseHandle(g_cbTermcap.handle);
++
+ #ifdef DYNAMIC_GETTEXT
+ dyn_libintl_end();
+ #endif
+***************
+*** 5002,5007 ****
+--- 4955,4962 ----
+ * screen buffer, and resize the buffer to match the current window
+ * size. We will use this as the size of our editing environment.
+ */
++ g_hConOut = g_cbTermcap.handle;
++ SetConsoleActiveScreenBuffer(g_hConOut);
+ ClearConsoleBuffer(g_attrCurrent);
+ ResizeConBufAndWindow(g_hConOut, Columns, Rows);
+ }
+***************
+*** 5045,5055 ****
+ cmodein &= ~(ENABLE_MOUSE_INPUT | ENABLE_WINDOW_INPUT);
+ SetConsoleMode(g_hConIn, cmodein);
+
+- #ifdef FEAT_RESTORE_ORIG_SCREEN
+- cb = exiting ? &g_cbOrig : &g_cbNonTermcap;
+- #else
+ cb = &g_cbNonTermcap;
+- #endif
+ RestoreConsoleBuffer(cb, p_rs);
+ SetConsoleCursorInfo(g_hConOut, &g_cci);
+
+--- 5000,5006 ----
+*** ../vim-7.4.850/src/version.c 2015-09-01 19:50:05.697404798 +0200
+--- src/version.c 2015-09-01 20:22:33.065197395 +0200
+***************
+*** 743,744 ****
+--- 743,746 ----
+ { /* Add new patch number below this line */
++ /**/
++ 851,
+ /**/
+
+--
+FATAL ERROR! SYSTEM HALTED! - Press any key to continue doing nothing.
+
+ /// Bram Moolenaar -- Bram@Moolenaar.net -- http://www.Moolenaar.net \\\
+/// sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ \\\
+\\\ an exciting new programming language -- http://www.Zimbu.org ///
+ \\\ help me help AIDS victims -- http://ICCF-Holland.org ///