[libvirt] [PATCH v2] util: activate directory override when used from library

Daniel P. Berrangé berrange at redhat.com
Thu Sep 5 10:52:09 UTC 2019


The Perl bindings for libvirt use the test driver for unit tests. This
tries to load the cpu_map/index.xml file, and when run from an
uninstalled build will fail.

The problem is that virFileActivateDirOverride is called by our various
binaries like libvirtd, virsh, but is not called when a 3rd party app
uses libvirt.so

To deal with this we allow the LIBVIRT_DIR_OVERRIDE=1 env variable to be
set and make virInitialize look for this. The 'run' script will set it,
so now build using this script to run against an uninstalled tree we
will correctly resolve files to the source tree.

Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
---
Changed in v2:

 - Use a separate function for env var override

 run.in                        |  7 ++++++
 src/libvirt.c                 |  2 ++
 src/libvirt_private.syms      |  3 ++-
 src/locking/lock_daemon.c     |  2 +-
 src/logging/log_daemon.c      |  2 +-
 src/remote/remote_daemon.c    |  2 +-
 src/security/virt-aa-helper.c |  2 +-
 src/util/virfile.c            | 40 ++++++++++++++++++++++++++---------
 src/util/virfile.h            |  3 ++-
 tests/testutils.c             |  2 +-
 tools/virsh.c                 |  2 +-
 tools/virt-admin.c            |  2 +-
 12 files changed, 50 insertions(+), 19 deletions(-)

diff --git a/run.in b/run.in
index 9a1c6ea11a..ed946a0899 100644
--- a/run.in
+++ b/run.in
@@ -60,6 +60,13 @@ else
 fi
 export PKG_CONFIG_PATH
 
+# Ensure that any 3rd party apps using libvirt.so from
+# the build tree get files resolved to the build/source
+# tree too. Typically useful for language bindings
+# running tests against non-installed libvirt.
+LIBVIRT_DIR_OVERRIDE=1
+export LIBVIRT_DIR_OVERRIDE
+
 # This is a cheap way to find some use-after-free and uninitialized
 # read problems when using glibc.
 random_val="$(awk 'BEGIN{srand(); print 1+int(255*rand())}' < /dev/null)"
diff --git a/src/libvirt.c b/src/libvirt.c
index 9650aaa453..a1ecd8bacc 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -247,6 +247,8 @@ virGlobalInit(void)
         virErrorInitialize() < 0)
         goto error;
 
+    virFileActivateDirOverrideForLib();
+
     if (getuid() != geteuid() ||
         getgid() != getegid()) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index a34d92f5ef..21cd6a8ef7 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1917,7 +1917,8 @@ virDirOpenQuiet;
 virDirRead;
 virFileAbsPath;
 virFileAccessibleAs;
-virFileActivateDirOverride;
+virFileActivateDirOverrideForLib;
+virFileActivateDirOverrideForProg;
 virFileBindMountDevice;
 virFileBuildPath;
 virFileCanonicalizePath;
diff --git a/src/locking/lock_daemon.c b/src/locking/lock_daemon.c
index ac242bf65c..edb61d74c0 100644
--- a/src/locking/lock_daemon.c
+++ b/src/locking/lock_daemon.c
@@ -1188,7 +1188,7 @@ int main(int argc, char **argv) {
         }
     }
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     if (!(config = virLockDaemonConfigNew(privileged))) {
         VIR_ERROR(_("Can't create initial configuration"));
diff --git a/src/logging/log_daemon.c b/src/logging/log_daemon.c
index f74e900aea..85c58aaa7b 100644
--- a/src/logging/log_daemon.c
+++ b/src/logging/log_daemon.c
@@ -960,7 +960,7 @@ int main(int argc, char **argv) {
         }
     }
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     if (!(config = virLogDaemonConfigNew(privileged))) {
         VIR_ERROR(_("Can't create initial configuration"));
diff --git a/src/remote/remote_daemon.c b/src/remote/remote_daemon.c
index 546328b24d..8cf9412128 100644
--- a/src/remote/remote_daemon.c
+++ b/src/remote/remote_daemon.c
@@ -1034,7 +1034,7 @@ int main(int argc, char **argv) {
 
     virUpdateSelfLastChanged(argv[0]);
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     while (1) {
         int optidx = 0;
diff --git a/src/security/virt-aa-helper.c b/src/security/virt-aa-helper.c
index 3f9d775acc..326cfaf52a 100644
--- a/src/security/virt-aa-helper.c
+++ b/src/security/virt-aa-helper.c
@@ -1427,7 +1427,7 @@ main(int argc, char **argv)
         exit(EXIT_FAILURE);
     }
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     /* Initialize the log system */
     virLogSetFromEnv();
diff --git a/src/util/virfile.c b/src/util/virfile.c
index 81a3c096eb..d9ac482435 100644
--- a/src/util/virfile.c
+++ b/src/util/virfile.c
@@ -1766,7 +1766,7 @@ virFileFindResource(const char *filename,
 
 
 /**
- * virFileActivateDirOverride:
+ * virFileActivateDirOverrideForProg:
  * @argv0: argv[0] of the calling program
  *
  * Look at @argv0 and try to detect if running from
@@ -1774,20 +1774,40 @@ virFileFindResource(const char *filename,
  * on the binary name, or '/.libs/' in the path
  */
 void
-virFileActivateDirOverride(const char *argv0)
+virFileActivateDirOverrideForProg(const char *argv0)
 {
-    char *file = strrchr(argv0, '/');
-    if (!file || file[1] == '\0')
-        return;
-    file++;
-    if (STRPREFIX(file, "lt-") ||
-        strstr(argv0, "/.libs/")) {
-        useDirOverride = true;
-        VIR_DEBUG("Activating build dir override for %s", argv0);
+    if (argv0 == NULL) {
+        if (getenv("LIBVIRT_DIR_OVERRIDE") != NULL)
+            useDirOverride = true;
+    } else {
+        char *file = strrchr(argv0, '/');
+        if (!file || file[1] == '\0')
+            return;
+        file++;
+        if (STRPREFIX(file, "lt-") ||
+            strstr(argv0, "/.libs/")) {
+            useDirOverride = true;
+            VIR_DEBUG("Activating build dir override for %s", argv0);
+        }
     }
 }
 
 
+/**
+ * virFileActivateDirOverrideForEnv:
+ *
+ * Look for LIBVIRT_DIR_OVERRIDE env var to see if
+ * we should find files from the build/src tree
+ * instead of install tree
+ */
+void
+virFileActivateDirOverrideForLib(void)
+{
+    if (getenv("LIBVIRT_DIR_OVERRIDE") != NULL)
+        useDirOverride = true;
+}
+
+
 /**
  * virFileLength:
  * @path: full path of the file
diff --git a/src/util/virfile.h b/src/util/virfile.h
index a8a5dd8074..2b037b00aa 100644
--- a/src/util/virfile.h
+++ b/src/util/virfile.h
@@ -193,8 +193,9 @@ char *virFileFindResourceFull(const char *filename,
                               const char *installdir,
                               const char *envname)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(4) ATTRIBUTE_NONNULL(5);
-void virFileActivateDirOverride(const char *argv0)
+void virFileActivateDirOverrideForProg(const char *argv0)
     ATTRIBUTE_NONNULL(1);
+void virFileActivateDirOverrideForLib(void);
 
 off_t virFileLength(const char *path, int fd) ATTRIBUTE_NONNULL(1);
 bool virFileIsDir (const char *file) ATTRIBUTE_NONNULL(1);
diff --git a/tests/testutils.c b/tests/testutils.c
index 8b2c51044e..003893dc44 100644
--- a/tests/testutils.c
+++ b/tests/testutils.c
@@ -992,7 +992,7 @@ int virTestMain(int argc,
 
     setenv("VIR_TEST_MOCK_PROGNAME", progname, 1);
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     if (virTestSetEnvPath() < 0)
         return EXIT_AM_HARDFAIL;
diff --git a/tools/virsh.c b/tools/virsh.c
index e76d242ec8..ec20f35a77 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -897,7 +897,7 @@ main(int argc, char **argv)
         return EXIT_FAILURE;
     }
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     if (!vshInit(ctl, cmdGroups, NULL))
         exit(EXIT_FAILURE);
diff --git a/tools/virt-admin.c b/tools/virt-admin.c
index 4ff006ffcb..e549ec1f83 100644
--- a/tools/virt-admin.c
+++ b/tools/virt-admin.c
@@ -1552,7 +1552,7 @@ main(int argc, char **argv)
         return EXIT_FAILURE;
     }
 
-    virFileActivateDirOverride(argv[0]);
+    virFileActivateDirOverrideForProg(argv[0]);
 
     if (!vshInit(ctl, cmdGroups, NULL))
         exit(EXIT_FAILURE);
-- 
2.21.0




More information about the libvir-list mailing list