[PATCH v2 4/5] qemu_passt: Deduplicate passt killing code

[Michal Privoznik <mprivozn@redhat.com>]

There are two places where we kill passt:

1) qemuPasstStop() - called transitively from qemuProcessStop(),
2) qemuPasstStart() - after failed start.

Now, the code from 2) lack error preservation (so if there's
another error during cleanup we might overwrite the original
error). Therefore, move the internals of qemuPasstStop() into a
separate function and call it from both places.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
---
 src/qemu/qemu_passt.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/qemu/qemu_passt.c b/src/qemu/qemu_passt.c
index 881205449b..a4cc9e7166 100644
--- a/src/qemu/qemu_passt.c
+++ b/src/qemu/qemu_passt.c
@@ -102,11 +102,9 @@ qemuPasstAddNetProps(virDomainObj *vm,
 }
 
 
-void
-qemuPasstStop(virDomainObj *vm,
-              virDomainNetDef *net)
+static void
+qemuPasstKill(const char *pidfile)
 {
-    g_autofree char *pidfile = qemuPasstCreatePidFilename(vm, net);
     virErrorPtr orig_err;
 
     virErrorPreserveLast(&orig_err);
@@ -118,6 +116,16 @@ qemuPasstStop(virDomainObj *vm,
 }
 
 
+void
+qemuPasstStop(virDomainObj *vm,
+              virDomainNetDef *net)
+{
+    g_autofree char *pidfile = qemuPasstCreatePidFilename(vm, net);
+
+    qemuPasstKill(pidfile);
+}
+
+
 int
 qemuPasstSetupCgroup(virDomainObj *vm,
                      virDomainNetDef *net,
@@ -147,7 +155,6 @@ qemuPasstStart(virDomainObj *vm,
     g_autofree char *errbuf = NULL;
     char macaddr[VIR_MAC_STRING_BUFLEN];
     size_t i;
-    pid_t pid = (pid_t) -1;
     int exitstatus = 0;
     int cmdret = 0;
 
@@ -289,10 +296,6 @@ qemuPasstStart(virDomainObj *vm,
     return 0;
 
  error:
-    ignore_value(virPidFileReadPathIfLocked(pidfile, &pid));
-    if (pid != -1)
-        virProcessKillPainfully(pid, true);
-    unlink(pidfile);
-
+    qemuPasstKill(pidfile);
     return -1;
 }
-- 
@@ -102,11 +102,9 @@ qemuPasstAddNetProps(virDomainObj *vm,
 }
 
 
-void
-qemuPasstStop(virDomainObj *vm,
-              virDomainNetDef *net)
+static void
+qemuPasstKill(const char *pidfile)
 {
-    g_autofree char *pidfile = qemuPasstCreatePidFilename(vm, net);
     virErrorPtr orig_err;
 
     virErrorPreserveLast(&orig_err);
@@ -118,6 +116,16 @@ qemuPasstStop(virDomainObj *vm,
 }
 
 
+void
+qemuPasstStop(virDomainObj *vm,
+              virDomainNetDef *net)
+{
+    g_autofree char *pidfile = qemuPasstCreatePidFilename(vm, net);
+
+    qemuPasstKill(pidfile);
+}
+
+
 int
 qemuPasstSetupCgroup(virDomainObj *vm,
                      virDomainNetDef *net,
@@ -147,7 +155,6 @@ qemuPasstStart(virDomainObj *vm,
     g_autofree char *errbuf = NULL;
     char macaddr[VIR_MAC_STRING_BUFLEN];
     size_t i;
-    pid_t pid = (pid_t) -1;
     int exitstatus = 0;
     int cmdret = 0;
 
@@ -289,10 +296,6 @@ qemuPasstStart(virDomainObj *vm,
     return 0;
 
  error:
-    ignore_value(virPidFileReadPathIfLocked(pidfile, &pid));
-    if (pid != -1)
-        virProcessKillPainfully(pid, true);
-    unlink(pidfile);
-
+    qemuPasstKill(pidfile);
     return -1;
 }
-- 
2.39.1