patch 8.2.5118: MS-Windows: sending a message to another Vim may hang
Problem: MS-Windows: sending a message to another Vim may hang if that Vim
is halted.
Solution: Add a timeout to serverSendToVim(). (Ken Takata, closes #10585)
diff --git a/src/os_mswin.c b/src/os_mswin.c
index 448b2bf..256da04 100644
--- a/src/os_mswin.c
+++ b/src/os_mswin.c
@@ -1971,6 +1971,10 @@
# define VIM_CLASSNAME "VIM_MESSAGES"
# define VIM_CLASSNAME_LEN (sizeof(VIM_CLASSNAME) - 1)
+// Timeout for sending a message to another Vim instance. Normally this works
+// instantly, but it may hang when the other Vim instance is halted.
+# define SENDMESSAGE_TIMEOUT (5 * 1000)
+
// Communication is via WM_COPYDATA messages. The message type is sent in
// the dwData parameter. Types are defined here.
# define COPYDATA_KEYS 0
@@ -1992,9 +1996,9 @@
/*
* Tell the other side what encoding we are using.
- * Errors are ignored.
+ * Return -1 if timeout happens. Other errors are ignored.
*/
- static void
+ static int
serverSendEnc(HWND target)
{
COPYDATASTRUCT data;
@@ -2002,8 +2006,11 @@
data.dwData = COPYDATA_ENCODING;
data.cbData = (DWORD)STRLEN(p_enc) + 1;
data.lpData = p_enc;
- (void)SendMessage(target, WM_COPYDATA, (WPARAM)message_window,
- (LPARAM)(&data));
+ if (SendMessageTimeout(target, WM_COPYDATA,
+ (WPARAM)message_window, (LPARAM)&data,
+ SMTO_ABORTIFHUNG, SENDMESSAGE_TIMEOUT, NULL) == 0)
+ return -1;
+ return 0;
}
/*
@@ -2061,6 +2068,7 @@
COPYDATASTRUCT reply;
char_u *res;
int retval;
+ DWORD_PTR dwret = 0;
char_u *str;
char_u *tofree;
@@ -2114,9 +2122,17 @@
reply.lpData = res;
reply.cbData = (DWORD)STRLEN(res) + 1;
- serverSendEnc(sender);
- retval = (int)SendMessage(sender, WM_COPYDATA,
- (WPARAM)message_window, (LPARAM)(&reply));
+ if (serverSendEnc(sender) < 0)
+ retval = -1;
+ else
+ {
+ if (SendMessageTimeout(sender, WM_COPYDATA,
+ (WPARAM)message_window, (LPARAM)&reply,
+ SMTO_ABORTIFHUNG, SENDMESSAGE_TIMEOUT, &dwret) == 0)
+ retval = -1;
+ else
+ retval = (int)dwret;
+ }
vim_free(tofree);
vim_free(res);
return retval;
@@ -2394,6 +2410,7 @@
HWND target;
COPYDATASTRUCT data;
long_u n = 0;
+ DWORD_PTR dwret = 0;
// The "name" argument is a magic cookie obtained from expand("<client>").
// It should be of the form 0xXXXXX - i.e. a C hex literal, which is the
@@ -2410,12 +2427,13 @@
data.cbData = (DWORD)STRLEN(reply) + 1;
data.lpData = reply;
- serverSendEnc(target);
- if (SendMessage(target, WM_COPYDATA, (WPARAM)message_window,
- (LPARAM)(&data)))
- return 0;
-
- return -1;
+ if (serverSendEnc(target) < 0)
+ return -1;
+ if (SendMessageTimeout(target, WM_COPYDATA,
+ (WPARAM)message_window, (LPARAM)&data,
+ SMTO_ABORTIFHUNG, SENDMESSAGE_TIMEOUT, &dwret) == 0)
+ return -1;
+ return dwret ? 0 : -1;
}
int
@@ -2432,6 +2450,7 @@
COPYDATASTRUCT data;
char_u *retval = NULL;
int retcode = 0;
+ DWORD_PTR dwret = 0;
char_u altname_buf[MAX_PATH];
// Execute locally if no display or target is ourselves
@@ -2463,9 +2482,13 @@
data.cbData = (DWORD)STRLEN(cmd) + 1;
data.lpData = cmd;
- serverSendEnc(target);
- if (SendMessage(target, WM_COPYDATA, (WPARAM)message_window,
- (LPARAM)(&data)) == 0)
+ if (serverSendEnc(target) < 0)
+ return -1;
+ if (SendMessageTimeout(target, WM_COPYDATA,
+ (WPARAM)message_window, (LPARAM)&data,
+ SMTO_ABORTIFHUNG, SENDMESSAGE_TIMEOUT, &dwret) == 0)
+ return -1;
+ if (dwret == 0)
return -1;
if (asExpr)