No Windows??? BAD CODER!!!

[ericol]

Hi there,
I tried to run this on window... to no avail. Basically, Go for windows does not support mmap and its siblings.

Not being the type that backs up that easily, I set to try to solve it (Bear in mind, I had Go installed locally because I found a nice tutorial few days ago, but haven't actually used it and have zero experience with the language).

I found online a Go package that is supposed to make mmap work in windows:

https://github.com/edsrzf/mmap-go

It didn't work out right out of the oven, so I tinkered with it and - several hours later - I had a working server running under windows :)

Still haven't used it so can't tell it it really works (I went as far as creating a collection, and the benchmark doesn't work). I haven't got any ide of how the prot flags work in Windows compared to *nix, and same for the flags, so I just put there what I thought was correct. Find below the patch for file.go

P.S.: HN brought me here.

diff --git a/src/loveoneanother.at/tiedot/file/file.go b/src/loveoneanother.at/tiedot/file/file.go
index ccb5a83..3170314 100644
--- a/src/loveoneanother.at/tiedot/file/file.go
+++ b/src/loveoneanother.at/tiedot/file/file.go
@@ -7,17 +7,24 @@ import (
    "log"
    "os"
    "sync"
-   "syscall"
+    "loveoneanother.at/tiedot/mmap"
 )

 type File struct {
    Name                 string
    Fh                   *os.File
    Append, Size, Growth uint64
-   Buf                  []byte
+   Buf                  mmap.MMap
    Sync                 *sync.RWMutex
 }

+//  void *mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset);
+
+// func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error)
+
+// func mmap(len int, prot, flags, hfile uintptr, off int64)
+
+//mmap.Mmap(int(file.Size), mmap.RDWR, 0, int(file.Fh.Fd()), 0 )
 // Open (create if non-exist) the file.
 func Open(name string, growth uint64) (file *File, err error) {
    if growth < 1 {
@@ -38,7 +45,7 @@ func Open(name string, growth uint64) (file *File, err error) {
    if file.Size == 0 {
        return file, file.Ensure(file.Growth)
    }
-   if file.Buf, err = syscall.Mmap(int(file.Fh.Fd()), 0, int(file.Size), syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED); err != nil {
+   if file.Buf, err = mmap.MapoRegion(file.Fh, int(file.Size), mmap.RDWR, 0, 0); err != nil {
        return
    }
    // find append position
@@ -72,7 +79,7 @@ func (file *File) Ensure(more uint64) (err error) {
        return
    }
    if file.Buf != nil {
-       if err = syscall.Munmap(file.Buf); err != nil {
+       if err = file.Buf.Unmap(); err != nil {
            return
        }
    }
@@ -85,9 +92,9 @@ func (file *File) Ensure(more uint64) (err error) {
    if err = file.Fh.Sync(); err != nil {
        return
    }
-   if newSize := int(file.Size + file.Growth); newSize < 0 {
+    if newSize := int(file.Size + file.Growth); newSize < 0 {
        log.Panicf("File %s is getting too large", file.Name)
-   } else if file.Buf, err = syscall.Mmap(int(file.Fh.Fd()), 0, newSize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED); err != nil {
+   } else if file.Buf, err = mmap.MapoRegion(file.Fh, newSize, mmap.RDWR, 0, 0); err != nil {
        return
    }
    file.Size += file.Growth
@@ -97,7 +104,7 @@ func (file *File) Ensure(more uint64) (err error) {

 // Close the file.
 func (file *File) Close() (err error) {
-   if err = syscall.Munmap(file.Buf); err != nil {
+   if err = file.Buf.Unmap(); err != nil {
        return
    }
    return file.Fh.Close()

[HouzuoGuo]

Oops, I should have mentioned that this has only been tested in Linux, sorry!

My laptop runs Windows 7 (as well as Linux), I should give it a try and see what the other problems are.

I will keep you updated.

[HouzuoGuo]

I made several fixes to mmap-go library and used it in tiedot beta, now it has been fully tested on Windows operating system (I tested it in Windows Server 2003 32-bit and Windows 7 64-bit).

Please check out beta branch!