[PATCH v2 1/4] os-posix: Add os_set_daemonize()

[Hanna Reitz]

The daemonizing functions in os-posix (os_daemonize() and
os_setup_post()) only daemonize the process if the static `daemonize`
variable is set.  Right now, it can only be set by os_parse_cmd_args().

In order to use os_daemonize() and os_setup_post() from the storage
daemon to have it be daemonized, we need some other way to set this
`daemonize` variable, because I would rather not tap into the system
emulator's arg-parsing code.  Therefore, this patch adds an
os_set_daemonize() function, which will return an error on os-win32
(because daemonizing is not supported there).

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
---
 include/sysemu/os-posix.h | 1 +
 include/sysemu/os-win32.h | 5 +++++
 os-posix.c                | 6 ++++++
 3 files changed, 12 insertions(+)

diff --git a/include/sysemu/os-posix.h b/include/sysemu/os-posix.h
index 2edf33658a..dd64fb401d 100644
--- a/include/sysemu/os-posix.h
+++ b/include/sysemu/os-posix.h
@@ -55,6 +55,7 @@ int os_mlock(void);
 typedef struct timeval qemu_timeval;
 #define qemu_gettimeofday(tp) gettimeofday(tp, NULL)
 
+int os_set_daemonize(bool d);
 bool is_daemonized(void);
 
 /**
diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
index 43f569b5c2..68af96907e 100644
--- a/include/sysemu/os-win32.h
+++ b/include/sysemu/os-win32.h
@@ -77,6 +77,11 @@ typedef struct {
 } qemu_timeval;
 int qemu_gettimeofday(qemu_timeval *tp);
 
+static inline int os_set_daemonize(bool d)
+{
+    return -ENOTSUP;
+}
+
 static inline bool is_daemonized(void)
 {
     return false;
diff --git a/os-posix.c b/os-posix.c
index ae6c9f2a5e..24692c8593 100644
--- a/os-posix.c
+++ b/os-posix.c
@@ -317,6 +317,12 @@ bool is_daemonized(void)
     return daemonize;
 }
 
+int os_set_daemonize(bool d)
+{
+    daemonize = d;
+    return 0;
+}
+
 int os_mlock(void)
 {
 #ifdef HAVE_MLOCKALL
-- 
2.34.1