[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH 1/2] qmp: Add 'openfd' command
From: |
Dr. David Alan Gilbert (git) |
Subject: |
[PATCH 1/2] qmp: Add 'openfd' command |
Date: |
Thu, 11 Jun 2020 12:17:02 +0100 |
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
The existing 'getfd' command imports an fd from the monitor via
SCM rights.
This command allows qemu to open the file for itself; this is convenient
primarily in testing, or with simple QMP clients.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
monitor/misc.c | 48 ++++++++++++++++++++++++++++++++++++++----------
qapi/misc.json | 23 ++++++++++++++++++++++-
2 files changed, 60 insertions(+), 11 deletions(-)
diff --git a/monitor/misc.c b/monitor/misc.c
index f5207cd242..d538af592a 100644
--- a/monitor/misc.c
+++ b/monitor/misc.c
@@ -1230,22 +1230,20 @@ static void hmp_acl_remove(Monitor *mon, const QDict
*qdict)
}
}
-void qmp_getfd(const char *fdname, Error **errp)
+/*
+ * Add a named fd to the monitor list.
+ * Returns true on success.
+ */
+static bool addfd(const char *fdname, int fd, Error **errp)
{
mon_fd_t *monfd;
- int fd, tmp_fd;
-
- fd = qemu_chr_fe_get_msgfd(&cur_mon->chr);
- if (fd == -1) {
- error_setg(errp, QERR_FD_NOT_SUPPLIED);
- return;
- }
+ int tmp_fd;
if (qemu_isdigit(fdname[0])) {
close(fd);
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "fdname",
"a name not starting with a digit");
- return;
+ return false;
}
qemu_mutex_lock(&cur_mon->mon_lock);
@@ -1259,7 +1257,7 @@ void qmp_getfd(const char *fdname, Error **errp)
qemu_mutex_unlock(&cur_mon->mon_lock);
/* Make sure close() is outside critical section */
close(tmp_fd);
- return;
+ return true;
}
monfd = g_malloc0(sizeof(mon_fd_t));
@@ -1268,6 +1266,36 @@ void qmp_getfd(const char *fdname, Error **errp)
QLIST_INSERT_HEAD(&cur_mon->fds, monfd, next);
qemu_mutex_unlock(&cur_mon->mon_lock);
+
+ return true;
+}
+
+void qmp_getfd(const char *fdname, Error **errp)
+{
+ int fd = qemu_chr_fe_get_msgfd(&cur_mon->chr);
+ if (fd == -1) {
+ error_setg(errp, QERR_FD_NOT_SUPPLIED);
+ return;
+ }
+
+ if (!addfd(fdname, fd, errp)) {
+ close(fd);
+ }
+}
+
+void qmp_openfd(const char *fdname, const char *filename, Error **errp)
+{
+ int fd;
+
+ fd = open(filename, O_RDWR | O_CREAT, S_IRWXU);
+ if (fd == -1) {
+ error_setg_errno(errp, errno, "Cannot open file '%s'", filename);
+ return;
+ }
+
+ if (!addfd(fdname, fd, errp)) {
+ close(fd);
+ }
}
void qmp_closefd(const char *fdname, Error **errp)
diff --git a/qapi/misc.json b/qapi/misc.json
index 99b90ac80b..baec07358e 100644
--- a/qapi/misc.json
+++ b/qapi/misc.json
@@ -952,7 +952,7 @@
##
# @closefd:
#
-# Close a file descriptor previously passed via SCM rights
+# Close a named file descriptor
#
# @fdname: file descriptor name
#
@@ -968,6 +968,27 @@
##
{ 'command': 'closefd', 'data': {'fdname': 'str'} }
+##
+# @openfd:
+#
+# Open a file descriptor. The file is opened read-write.
+#
+# @fdname: file descriptor name
+# @filename: file name
+#
+# Returns: Nothing on success
+#
+# Since: 5.1
+#
+# Example:
+#
+# -> { "execute": "openfd", "arguments": { "fdname": "null",
+# "filename": "/dev/null" } }
+# <- { "return": {} }
+#
+##
+{ 'command': 'openfd', 'data': {'fdname': 'str', 'filename': 'str'} }
+
##
# @MemoryInfo:
#
--
2.26.2