Merge pull request #355 from avih/utf8-output-speedup

win32: UTF8_OUTPUT: speedup for big outputs

1 files changed, 8 insertions, 2 deletions

diff --git a/win32/winansi.c b/win32/winansi.c
index c88c096d2..591154378 100644
--- a/win32/winansi.c
+++ b/win32/winansi.c
@@ -1457,10 +1457,16 @@ static int writeCon_utf8(int fd, const char *u8buf, size_t u8siz)
         static int state = 0;  // -1: bad, 0-3: remaining cp bytes (0: done/new)
         static uint32_t codepoint = 0;  // accumulated from up to 4 UTF8 bytes
 
+        // not a state, only avoids re-alloc on every call
+        static const int wbufwsiz = 4096;
+        static wchar_t *wbuf = 0;
+
         HANDLE h = (HANDLE)_get_osfhandle(fd);
-        wchar_t wbuf[256];
         int wlen = 0;
 
+        if (!wbuf)
+                wbuf = xmalloc(wbufwsiz * sizeof(wchar_t));
+
         // ASCII7 uses least logic, then UTF8 continuations, UTF8 lead, errors
         while (u8siz--) {
                 unsigned char c = *u8buf++;
@@ -1512,7 +1518,7 @@ static int writeCon_utf8(int fd, const char *u8buf, size_t u8siz)
                 }
 
                 // flush if we have less than two empty spaces
-                if (wlen > ARRAY_SIZE(wbuf) - 2) {
+                if (wlen > wbufwsiz - 2) {
                         if (!WriteConsoleW(h, wbuf, wlen, 0, 0))
                                 return -1;
                         wlen = 0;