From 29bed7cf5dfedeccd799c529184bc53aee956e20 Mon Sep 17 00:00:00 2001
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 =?UTF-8?q?=D0=B5=D0=B2=20=28Leonid=20Yuriev=29?= <leo@yuriev.ru>
Date: Mon, 7 Apr 2025 12:13:27 +0300
Subject: [PATCH] =?UTF-8?q?mdbx:=20=D0=B8=D0=B3=D0=BD=D0=BE=D1=80=D0=B8?=
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---
 src/api-copy.c | 22 ++++++++++++++++------
 src/osal.c     |  2 +-
 src/osal.h     |  1 +
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/src/api-copy.c b/src/api-copy.c
index ca109d84..9f0ce892 100644
--- a/src/api-copy.c
+++ b/src/api-copy.c
@@ -766,14 +766,24 @@ __cold static int copy2pathname(MDBX_txn *txn, const pathchar_t *dest_path, MDBX
     lock_op.l_whence = SEEK_SET;
     lock_op.l_start = 0;
     lock_op.l_len = OFF_T_MAX;
-    if (MDBX_FCNTL(newfd, MDBX_F_SETLK, &lock_op)
-#if (defined(__linux__) || defined(__gnu_linux__)) && defined(LOCK_EX) &&                                              \
-    (!defined(__ANDROID_API__) || __ANDROID_API__ >= 24)
-        || flock(newfd, LOCK_EX | LOCK_NB)
-#endif /* Linux */
-    )
+    if (MDBX_FCNTL(newfd, MDBX_F_SETLK, &lock_op))
       rc = errno;
   }
+
+#if defined(LOCK_EX) && (!defined(__ANDROID_API__) || __ANDROID_API__ >= 24)
+  if (rc == MDBX_SUCCESS && flock(newfd, LOCK_EX | LOCK_NB)) {
+    const int err_flock = errno, err_fs = osal_check_fs_local(newfd, 0);
+    if (err_flock != EAGAIN || err_fs != MDBX_EREMOTE) {
+      ERROR("%s flock(%" MDBX_PRIsPATH ") error %d, remote-fs check status %d", "unexpected", dest_path, err_flock,
+            err_fs);
+      rc = err_flock;
+    } else {
+      WARNING("%s flock(%" MDBX_PRIsPATH ") error %d, remote-fs check status %d", "ignore", dest_path, err_flock,
+              err_fs);
+    }
+  }
+#endif /* LOCK_EX && ANDROID_API >= 24 */
+
 #endif /* Windows / POSIX */
 
   if (rc == MDBX_SUCCESS)
diff --git a/src/osal.c b/src/osal.c
index ec2e0d7c..0ba44b61 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -1745,7 +1745,7 @@ MDBX_INTERNAL int osal_check_fs_incore(mdbx_filehandle_t handle) {
   return MDBX_RESULT_FALSE;
 }
 
-static int osal_check_fs_local(mdbx_filehandle_t handle, int flags) {
+MDBX_INTERNAL int osal_check_fs_local(mdbx_filehandle_t handle, int flags) {
 #if defined(_WIN32) || defined(_WIN64)
   if (globals.running_under_Wine && !(flags & MDBX_EXCLUSIVE))
     return ERROR_NOT_CAPABLE /* workaround for Wine */;
diff --git a/src/osal.h b/src/osal.h
index 484bbab8..06f58c60 100644
--- a/src/osal.h
+++ b/src/osal.h
@@ -481,6 +481,7 @@ MDBX_INTERNAL int osal_resume_threads_after_remap(mdbx_handle_array_t *array);
 MDBX_INTERNAL int osal_msync(const osal_mmap_t *map, size_t offset, size_t length, enum osal_syncmode_bits mode_bits);
 MDBX_INTERNAL int osal_check_fs_rdonly(mdbx_filehandle_t handle, const pathchar_t *pathname, int err);
 MDBX_INTERNAL int osal_check_fs_incore(mdbx_filehandle_t handle);
+MDBX_INTERNAL int osal_check_fs_local(mdbx_filehandle_t handle, int flags);
 
 MDBX_MAYBE_UNUSED static inline uint32_t osal_getpid(void) {
   STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));