[systemd-commits] src/sysv-generator test/sysv-generator-test.py

[Martin Pitt]

 src/sysv-generator/sysv-generator.c |   12 +++++++++++
 test/sysv-generator-test.py         |   39 ++++++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

New commits:
commit 77354c7e6f096a447245a8781c1eaa4acbe67089
Author: Martin Pitt <martin.pitt at ubuntu.com>
Date:   Wed Jan 21 10:25:14 2015 +0100

    sysv-generator: Replace Provides: symlinks with real units
    
    Since commit b7e7184 the SysV generator creates symlinks for all "Provides:" in
    the LSB header. However, this is too greedy; there are cases where the
    creation of a unit .service file fails because of an already existing
    symlink with the same name:
    
     - Backup files such as /etc/init.d/foo.bak still have "Provides: foo", and
       thus get a foo.service -> foo.bak.service link. foo.bak would not be enabled
       in rcN.d/, but we (deliberately) create units for all executables in init.d/
       so that a manual "systemctl start" works. If foo.bak is processed before,
       the symlink already exists.
    
     - init.d/bar has "Provides: foo", while there also is a real init.d/foo. The
       former would create a link foo.service -> bar.service, while the latter
       would fail to create the real foo.service.
    
    If we encounter an existing symlink, just remove it before writing a real unit.
    
    Note that two init.d scripts "foo" and "bar" which both provide the same name
    "common" already work. The first processed init script wins and creates the
    "common.service" symlink, and the second just fails to create the symlink
    again. Thus create an additional test case for this to ensure that it keeps
    working sensibly.
    
    https://bugs.debian.org/775404

diff --git a/src/sysv-generator/sysv-generator.c b/src/sysv-generator/sysv-generator.c
index a47b072..3279c7f 100644
--- a/src/sysv-generator/sysv-generator.c
+++ b/src/sysv-generator/sysv-generator.c
@@ -147,6 +147,7 @@ static int generate_unit_file(SysvStub *s) {
         _cleanup_free_ char *wants = NULL;
         _cleanup_free_ char *conflicts = NULL;
         int r;
+        struct stat st;
 
         before = strv_join(s->before, " ");
         if (!before)
@@ -168,6 +169,14 @@ static int generate_unit_file(SysvStub *s) {
         if (!unit)
                 return log_oom();
 
+        /* We might already have a symlink with the same name from a Provides:,
+         * or from backup files like /etc/init.d/foo.bak. Real scripts always win,
+         * so remove an existing link */
+        if (lstat(unit, &st) == 0 && S_ISLNK(st.st_mode)) {
+                log_warning("Overwriting existing symlink %s with real service", unit);
+                unlink(unit);
+        }
+
         f = fopen(unit, "wxe");
         if (!f)
                 return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
@@ -343,6 +352,8 @@ static int load_sysv(SysvStub *s) {
         if (!f)
                 return errno == ENOENT ? 0 : -errno;
 
+        log_debug("Loading SysV script %s", s->path);
+
         while (!feof(f)) {
                 char l[LINE_MAX], *t;
 
@@ -492,6 +503,7 @@ static int load_sysv(SysvStub *s) {
                                                 continue;
 
                                         if (unit_name_to_type(m) == UNIT_SERVICE) {
+                                                log_debug("Adding Provides: alias '%s' for '%s'", m, s->name);
                                                 r = add_alias(s->name, m);
                                         } else {
                                                 /* NB: SysV targets
diff --git a/test/sysv-generator-test.py b/test/sysv-generator-test.py
index df13c98..5098519 100644
--- a/test/sysv-generator-test.py
+++ b/test/sysv-generator-test.py
@@ -271,6 +271,25 @@ class SysvGeneratorTest(unittest.TestCase):
             self.assertEqual(os.readlink(os.path.join(self.out_dir, f)),
                              'foo.service')
 
+    def test_same_provides_in_multiple_scripts(self):
+        '''multiple init.d scripts provide the same name'''
+
+        self.add_sysv('foo', {'Provides': 'foo common'}, enable=True, prio=1)
+        self.add_sysv('bar', {'Provides': 'bar common'}, enable=True, prio=2)
+        err, results = self.run_generator()
+        self.assertEqual(sorted(results), ['bar.service', 'foo.service'])
+        # should create symlink for the alternative name for either unit
+        self.assertIn(os.readlink(os.path.join(self.out_dir, 'common.service')),
+                      ['foo.service', 'bar.service'])
+
+    def test_provide_other_script(self):
+        '''init.d scripts provides the name of another init.d script'''
+
+        self.add_sysv('foo', {'Provides': 'foo bar'}, enable=True)
+        self.add_sysv('bar', {'Provides': 'bar'}, enable=True)
+        err, results = self.run_generator()
+        self.assertEqual(sorted(results), ['bar.service', 'foo.service'])
+
     def test_nonexecutable_script(self):
         '''ignores non-executable init.d script'''
 
@@ -328,6 +347,26 @@ class SysvGeneratorTest(unittest.TestCase):
 
         self.assert_enabled('foo.service', [2, 3, 4, 5])
 
+    def test_backup_file(self):
+        '''init.d script with backup file'''
+
+        script = self.add_sysv('foo', {}, enable=True)
+        # backup files (not enabled in rcN.d/)
+        shutil.copy(script, script + '.bak')
+        shutil.copy(script, script + '.old')
+
+        err, results = self.run_generator()
+        print(err)
+        self.assertEqual(sorted(results),
+                         ['foo.bak.service', 'foo.old.service', 'foo.service'])
+
+        # ensure we don't try to create a symlink to itself
+        self.assertNotIn(err, 'itself')
+
+        self.assert_enabled('foo.service', [2, 3, 4, 5])
+        self.assert_enabled('foo.bak.service', [])
+        self.assert_enabled('foo.old.service', [])
+
 
 if __name__ == '__main__':
     unittest.main(testRunner=unittest.TextTestRunner(stream=sys.stdout, verbosity=2))