vim-patch:8.1.2094: the fileio.c file is too big

Problem:    The fileio.c file is too big.
Solution:   Move buf_write() to bufwrite.c. (Yegappan Lakshmanan,
            closes vim/vim#4990)

c079f0fed1

Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>

cmake.config/iwyu/mapping.imp

@@ -20,6 +20,7 @@
   { include: [ '"autocmd.h.generated.h"', private, '"nvim/autocmd.h"', public ] },
   { include: [ '"buffer.h.generated.h"', private, '"nvim/buffer.h"', public ] },
   { include: [ '"buffer_updates.h.generated.h"', private, '"nvim/buffer_updates.h"', public ] },
+  { include: [ '"bufwrite.h.generated.h"', private, '"nvim/bufwrite.h"', public ] },
   { include: [ '"change.h.generated.h"', private, '"nvim/change.h"', public ] },
   { include: [ '"channel.h.generated.h"', private, '"nvim/channel.h"', public ] },
   { include: [ '"charset.h.generated.h"', private, '"nvim/charset.h"', public ] },

src/nvim/bufwrite.h

@@ -0,0 +1,11 @@
+#ifndef NVIM_BUFWRITE_H
+#define NVIM_BUFWRITE_H
+
+#include "nvim/buffer_defs.h"
+#include "nvim/ex_cmds_defs.h"
+
+#ifdef INCLUDE_GENERATED_DECLARATIONS
+# include "bufwrite.h.generated.h"
+#endif
+
+#endif  // NVIM_BUFWRITE_H

src/nvim/diff.c

@@ -22,6 +22,7 @@
 #include "nvim/ascii.h"
 #include "nvim/autocmd.h"
 #include "nvim/buffer.h"
+#include "nvim/bufwrite.h"
 #include "nvim/change.h"
 #include "nvim/charset.h"
 #include "nvim/cursor.h"

src/nvim/ex_cmds.c

@@ -23,6 +23,7 @@
 #include "nvim/buffer.h"
 #include "nvim/buffer_defs.h"
 #include "nvim/buffer_updates.h"
+#include "nvim/bufwrite.h"
 #include "nvim/change.h"
 #include "nvim/channel.h"
 #include "nvim/charset.h"

src/nvim/ex_cmds2.c

@@ -15,6 +15,7 @@
 #include "nvim/ascii.h"
 #include "nvim/autocmd.h"
 #include "nvim/buffer.h"
+#include "nvim/bufwrite.h"
 #include "nvim/change.h"
 #include "nvim/channel.h"
 #include "nvim/eval.h"

src/nvim/fileio.h

@@ -20,8 +20,29 @@
 
 typedef varnumber_T (*CheckItem)(void *expr, const char *name);
 
+enum {
+  FIO_LATIN1 = 0x01,       // convert Latin1
+  FIO_UTF8 = 0x02,         // convert UTF-8
+  FIO_UCS2 = 0x04,         // convert UCS-2
+  FIO_UCS4 = 0x08,         // convert UCS-4
+  FIO_UTF16 = 0x10,        // convert UTF-16
+  FIO_ENDIAN_L = 0x80,     // little endian
+  FIO_NOCONVERT = 0x2000,  // skip encoding conversion
+  FIO_UCSBOM = 0x4000,     // check for BOM at start of file
+  FIO_ALL = -1,            // allow all formats
+};
+
+// When converting, a read() or write() may leave some bytes to be converted
+// for the next call.  The value is guessed...
+#define CONV_RESTLEN 30
+
+#define WRITEBUFSIZE         8192    // size of normal write buffer
+
+// We have to guess how much a sequence of bytes may expand when converting
+// with iconv() to be able to allocate a buffer.
+#define ICONV_MULT 8
+
 #ifdef INCLUDE_GENERATED_DECLARATIONS
-// Events for autocommands
 # include "fileio.h.generated.h"
 #endif
 #endif  // NVIM_FILEIO_H