From 68a116c380130aeb15ac50e7f687ba12777e3b64 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Mon, 23 Jan 2023 19:00:18 +0000
Subject: [PATCH] FST writer does not flush valpos_mem on Windows. Issue #596

---
 NEWS.md             |  2 ++
 thirdparty/fstapi.c | 24 +++++++++++++++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 90ac7d5d..57df44a3 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,4 +1,6 @@
 ## Unreleased changes
+- Initial signal values for certain types were not dumped correctly in
+  FST files on Windows (#596).
 
 ## Version 1.8.0 - 2023-01-22
 - The `--disable-opt` and `--native` elaborate options which were
diff --git a/thirdparty/fstapi.c b/thirdparty/fstapi.c
index 93d4f78b..1ac39631 100644
--- a/thirdparty/fstapi.c
+++ b/thirdparty/fstapi.c
@@ -1042,9 +1042,6 @@ static void fstDestroyMmaps(struct fstWriterContext *xc, int is_closing)
 (void)is_closing;
 #endif
 
-fstMunmap(xc->valpos_mem, xc->maxhandle * 4 * sizeof(uint32_t));
-xc->valpos_mem = NULL;
-
 #if defined __CYGWIN__ || defined __MINGW32__
 if(xc->curval_mem)
         {
@@ -1056,6 +1053,24 @@ if(xc->curval_mem)
                 size_t i;
                 size_t __len = xc->maxvalpos;
 
+                lseek(__fd, 0, SEEK_SET);
+                for(i=0;i<__len;i+=SSIZE_MAX)
+                        {
+                        write(__fd, pnt + i, ((__len - i) >= SSIZE_MAX) ? SSIZE_MAX : (__len - i));
+                        }
+                lseek(__fd, cur_offs, SEEK_SET);
+                }
+        }
+ if(xc->valpos_mem)
+        {
+        if(!is_closing) /* need to flush out for next emulated mmap() read */
+                {
+                char *pnt = (char *)xc->valpos_mem;
+                int __fd = fileno(xc->valpos_handle);
+                fst_off_t cur_offs = lseek(__fd, 0, SEEK_CUR);
+                size_t i;
+                size_t __len = xc->maxhandle * 4 * sizeof(uint32_t);
+
                 lseek(__fd, 0, SEEK_SET);
                 for(i=0;i<__len;i+=SSIZE_MAX)
                         {
@@ -1066,6 +1081,9 @@ if(xc->curval_mem)
         }
 #endif
 
+fstMunmap(xc->valpos_mem, xc->maxhandle * 4 * sizeof(uint32_t));
+xc->valpos_mem = NULL;
+
 fstMunmap(xc->curval_mem, xc->maxvalpos);
 xc->curval_mem = NULL;
 }
-- 
2.39.2