tests: point $HOME and $XDG_* into usable fake root directory

A long time ago we added some lines to "poison" the environment of
test programs (specifically $HOME and $XDG_*) with nonexisting
unusable paths so that any test program attempting to use the normal
settings of those variables (which point into the filesystem of the
system running the test) would fail (rather than silently messing up
the test system).

At some later time, someone wrote tests for hostdev devices that
required that virGetUserRuntimeDirectory() (which normally uses either
$XDG_RUNTIME_DIR or $HOME) return a directory that could actually be
used as a part of the test; this was solved by mocking
virGetUserRuntimeDirectory() to return a path underneath
$LIBVIRT_FAKE_ROOT_DIR (which is created each time a test starts).

Much much later, I wanted to add validation of the directory returned
by virGetUserRuntimeDirectory(), but when this validation was added,
the poisoned values that had been set (back in paragraph one "a long
time ago") caused this validation to fail.

My first attempt to fix this was to make the mocked
virGetUserRuntimeDirectory() more generally available, and turn it on
for all the tests that failed. But then I realized that a better
solution would be to instead "nourish" (rather than "poison" - get
it?) $HOME and $XDG_* with directories created under
$LIBVIRT_FAKE_ROOT_DIR. This way we are actually testing the real
virGetUserRuntimeDirectory() and any future validation, and also make
some other tests cover more actual code in the future.

In this patch the poisoning of the environment is removed, the call to
the function creating the fake root dir is moved up to that location,
and as a part of creating the fake root dir, we also set the
aforementioned environment variables and create the directories
associated with them (since the tests assume that they already exist).

The now-redundant original mock of virGetUserRuntimeDirectory() will
be removed in another patch.

Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

diff --git a/tests/testutils.c b/tests/testutils.c
index 814391b804afd8c9bdeee33785135cc7a6023c1f..c984f66d0e3a6822598b3e33489369ad70a8bbd0 100644 (file)
--- a/tests/testutils.c
+++ b/tests/testutils.c
@@ -779,6 +779,20 @@ virTestSetEnvPath(void)
 
 #define FAKEROOTDIRTEMPLATE abs_builddir "/fakerootdir-XXXXXX"
 
+static int
+virTestFakeEnvSubDirInit(const char *envName, const char *fakeRootName, const char *fakeSubDirName)
+{
+    g_autofree char *envVal = g_build_filename(fakeRootName, fakeSubDirName, NULL);
+
+    if (g_mkdir(envVal, 0777) < 0) {
+        fprintf(stderr, "Cannot create fake %s directory at %s", envName, envVal);
+        return -1;
+    }
+
+    g_setenv(envName, envVal, TRUE);
+    return 0;
+}
+
 char*
 virTestFakeRootDirInit(void)
 {
@@ -791,6 +805,22 @@ virTestFakeRootDirInit(void)
 
     g_setenv("LIBVIRT_FAKE_ROOT_DIR", fakerootdir, TRUE);
 
+    /* the glib g_get_user_*_dir() functions use these environment variables to
+     * determine locations for various data/log/config files. Setting them here
+     * will assure that code under test that is using those directories won't pollute
+     * the system under test.
+     */
+    if (virTestFakeEnvSubDirInit("HOME", fakerootdir, "home") < 0)
+        return NULL;
+    if (virTestFakeEnvSubDirInit("XDG_RUNTIME_DIR", fakerootdir, "user-runtime-dir") < 0)
+        return NULL;
+    if (virTestFakeEnvSubDirInit("XDG_DATA_HOME", fakerootdir, "user-data-home") < 0)
+        return NULL;
+    if (virTestFakeEnvSubDirInit("XDG_CACHE_HOME", fakerootdir, "user-cache-home") < 0)
+        return NULL;
+    if (virTestFakeEnvSubDirInit("XDG_CONFIG_HOME", fakerootdir, "user-config-home") < 0)
+        return NULL;
+
     return g_steal_pointer(&fakerootdir);
 }
 
@@ -829,11 +859,8 @@ int virTestMain(int argc,
         preloads[npreloads] = NULL;
     }
 
-    g_setenv("HOME", "/bad-test-used-env-home", TRUE);
-    g_setenv("XDG_RUNTIME_DIR", "/bad-test-used-env-xdg-runtime-dir", TRUE);
-    g_setenv("XDG_DATA_HOME", "/bad-test-used-env-xdg-data-home", TRUE);
-    g_setenv("XDG_CACHE_HOME", "/bad-test-used-env-xdg-cache-home", TRUE);
-    g_setenv("XDG_CONFIG_HOME", "/bad-test-used-env-xdg-config-home", TRUE);
+    if (!(fakerootdir = virTestFakeRootDirInit()))
+        return EXIT_FAILURE;
 
     va_start(ap, func);
     while ((lib = va_arg(ap, const char *))) {
@@ -907,9 +934,6 @@ int virTestMain(int argc,
 
     failedTests = virBitmapNew(1);
 
-    if (!(fakerootdir = virTestFakeRootDirInit()))
-        return EXIT_FAILURE;
-
     ret = (func)();
 
     virResetLastError();