From 6527435c0fc28b3cfd7fd1a2bca56030672f58df Mon Sep 17 00:00:00 2001
From: Nuno Cruces <ncruces@users.noreply.github.com>
Date: Sat, 21 Jan 2023 12:24:36 +0000
Subject: [PATCH] File open fixes.

---
 conn.go        | 11 +++++++++++
 sqlite3/main.c |  7 ++++---
 vfs.go         | 18 ++++++------------
 3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/conn.go b/conn.go
index d85bd9b..307bc50 100644
--- a/conn.go
+++ b/conn.go
@@ -241,6 +241,17 @@ func getString(memory api.Memory, ptr, maxlen uint32) string {
 	}
 }
 
+func (c *Conn) getFile(f *os.File) uint32 {
+	for i := range c.files {
+		if c.files[i] == nil {
+			c.files[i] = f
+			return uint32(i)
+		}
+	}
+	c.files = append(c.files, f)
+	return uint32(len(c.files) - 1)
+}
+
 type connContext struct{}
 
 const ptrSize = 4
diff --git a/sqlite3/main.c b/sqlite3/main.c
index 272081a..eb2e532 100644
--- a/sqlite3/main.c
+++ b/sqlite3/main.c
@@ -20,7 +20,7 @@ int go_full_pathname(sqlite3_vfs *, const char *zName, int nOut, char *zOut);
 
 struct go_file {
   sqlite3_file base;
-  int fd;
+  int id;
 };
 
 int go_close(sqlite3_file *);
@@ -59,8 +59,9 @@ static int go_open_c(sqlite3_vfs *vfs, sqlite3_filename zName,
       .xSectorSize = no_sector_size,
       .xDeviceCharacteristics = no_device_characteristics,
   };
-  file->pMethods = &go_io;
-  return go_open(vfs, zName, file, flags, pOutFlags);
+  int rc = go_open(vfs, zName, file, flags, pOutFlags);
+  file->pMethods = rc == SQLITE_OK ? &go_io : NULL;
+  return rc;
 }
 
 int sqlite3_os_init() {
diff --git a/vfs.go b/vfs.go
index a573823..6c045af 100644
--- a/vfs.go
+++ b/vfs.go
@@ -186,19 +186,13 @@ func vfsOpen(ctx context.Context, mod api.Module, vfs, zName, file, flags, pOutF
 		return uint32(CANTOPEN)
 	}
 
-	var id int
-	for i := range c.files {
-		if c.files[i] == nil {
-			id = i
-			c.files[i] = f
-			goto found
-		}
+	if ok := mod.Memory().WriteUint32Le(file+ptrSize, c.getFile(f)); !ok {
+		panic(rangeErr)
 	}
-	id = len(c.files)
-	c.files = append(c.files, f)
-found:
-
-	if ok := mod.Memory().WriteUint32Le(file+ptrSize, uint32(id)); !ok {
+	if pOutFlags == 0 {
+		return _OK
+	}
+	if ok := mod.Memory().WriteUint32Le(pOutFlags, flags); !ok {
 		panic(rangeErr)
 	}
 	return _OK