[PATCH v4 04/29] tools/libxl: Introduce libxl__kill()

[Andrew Cooper <andrew.cooper3@citrix.com>]

as a wrapper to kill(2), and use it in preference to sendsig in
libxl_save_callout.c.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>

---
v3: Fix typo, add _hidden

Logically new in v2 - split out from a v1 change which was itself a
cherrypick-and-modify from the AO Abort series
---
 tools/libxl/libxl_aoutils.c      |   15 +++++++++++++++
 tools/libxl/libxl_internal.h     |    2 ++
 tools/libxl/libxl_save_callout.c |   10 ++--------
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/tools/libxl/libxl_aoutils.c b/tools/libxl/libxl_aoutils.c
index 0931eee..274ef39 100644
--- a/tools/libxl/libxl_aoutils.c
+++ b/tools/libxl/libxl_aoutils.c
@@ -621,3 +621,18 @@ bool libxl__async_exec_inuse(const libxl__async_exec_state *aes)
     assert(time_inuse == child_inuse);
     return child_inuse;
 }
+
+void libxl__kill(libxl__gc *gc, pid_t pid, int sig, const char *what)
+{
+    int r = kill(pid, sig);
+    if (r) LOGE(WARN, "failed to kill() %s [%lu] (signal %d)",
+                what, (unsigned long)pid, sig);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 19fc425..7ccbf55 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -2244,6 +2244,8 @@ struct libxl__async_exec_state {
 int libxl__async_exec_start(libxl__async_exec_state *aes);
 bool libxl__async_exec_inuse(const libxl__async_exec_state *aes);
 
+_hidden void libxl__kill(libxl__gc *gc, pid_t pid, int sig, const char *what);
+
 /*----- device addition/removal -----*/
 
 typedef struct libxl__ao_device libxl__ao_device;
diff --git a/tools/libxl/libxl_save_callout.c b/tools/libxl/libxl_save_callout.c
index 087c2d5..b82a5c1 100644
--- a/tools/libxl/libxl_save_callout.c
+++ b/tools/libxl/libxl_save_callout.c
@@ -244,12 +244,6 @@ static void run_helper(libxl__egc *egc, libxl__save_helper_state *shs,
     libxl__carefd_close(childs_pipes[1]);
     helper_failed(egc, shs, rc);;
 }
-static void sendsig(libxl__gc *gc, libxl__save_helper_state *shs, int sig)
-{
-    int r = kill(shs->child.pid, sig);
-    if (r) LOGE(WARN, "failed to kill save/restore helper [%lu] (signal %d)",
-                (unsigned long)shs->child.pid, sig);
-}
 
 static void helper_failed(libxl__egc *egc, libxl__save_helper_state *shs,
                           int rc)
@@ -266,7 +260,7 @@ static void helper_failed(libxl__egc *egc, libxl__save_helper_state *shs,
         return;
     }
 
-    sendsig(gc, shs, SIGKILL);
+    libxl__kill(gc, shs->child.pid, SIGKILL, "save/restore helper");
 }
 
 static void helper_stop(libxl__egc *egc, libxl__ao_abortable *abrt, int rc)
@@ -282,7 +276,7 @@ static void helper_stop(libxl__egc *egc, libxl__ao_abortable *abrt, int rc)
     if (!shs->rc)
         shs->rc = rc;
 
-    sendsig(gc, shs, SIGTERM);
+    libxl__kill(gc, shs->child.pid, SIGTERM, "save/restore helper");
 }
 
 static void helper_stdout_readable(libxl__egc *egc, libxl__ev_fd *ev,
-- 
1.7.10.4