def add_if_new(self, name, ref):
"""Add a new reference only if it does not already exist.
This method follows symrefs, and only ensures that the last ref in the
chain does not exist.
:param name: The refname to set.
:param ref: The new sha the refname will refer to.
:return: True if the add was successful, False otherwise.
"""
try:
realname, contents = self._follow(name)
if contents is not None:
return False
except KeyError:
realname = name
self._check_refname(realname)
filename = self.refpath(realname)
ensure_dir_exists(os.path.dirname(filename))
f = GitFile(filename, 'wb')
try:
if os.path.exists(filename) or name in self.get_packed_refs():
f.abort()
return False
try:
f.write(ref+"\n")
except (OSError, IOError):
f.abort()
raise
finally:
f.close()
return True
def add_if_new(self, name, ref):
"""Add a new reference only if it does not already exist.
This method follows symrefs, and only ensures that the last ref in the
chain does not exist.
:param name: The refname to set.
:param ref: The new sha the refname will refer to.
:return: True if the add was successful, False otherwise.
"""
try:
realname, contents = self._follow(name)
if contents is not None:
return False
except KeyError:
realname = name
self._check_refname(realname)
filename = self.refpath(realname)
ensure_dir_exists(os.path.dirname(filename))
f = GitFile(filename, 'wb')
try:
if os.path.exists(filename) or name in self.get_packed_refs():
f.abort()
return False
try:
f.write(ref + "\n")
except (OSError, IOError):
f.abort()
raise
finally:
f.close()
return True
def set_symbolic_ref(self, name, other):
"""Make a ref point at another ref.
:param name: Name of the ref to set
:param other: Name of the ref to point at
"""
self._check_refname(name)
self._check_refname(other)
filename = self.refpath(name)
try:
f = GitFile(filename, 'wb')
try:
f.write(SYMREF + other + '\n')
except (IOError, OSError):
f.abort()
raise
finally:
f.close()
def set_symbolic_ref(self, name, other):
"""Make a ref point at another ref.
:param name: Name of the ref to set
:param other: Name of the ref to point at
"""
self._check_refname(name)
self._check_refname(other)
filename = self.refpath(name)
try:
f = GitFile(filename, 'wb')
try:
f.write(SYMREF + other + '\n')
except (IOError, OSError):
f.abort()
raise
finally:
f.close()
def _remove_packed_ref(self, name):
if self._packed_refs is None:
return
filename = os.path.join(self.path, 'packed-refs')
# reread cached refs from disk, while holding the lock
f = GitFile(filename, 'wb')
try:
self._packed_refs = None
self.get_packed_refs()
if name not in self._packed_refs:
return
del self._packed_refs[name]
if name in self._peeled_refs:
del self._peeled_refs[name]
write_packed_refs(f, self._packed_refs, self._peeled_refs)
f.close()
finally:
f.abort()
def _remove_packed_ref(self, name):
if self._packed_refs is None:
return
filename = os.path.join(self.path, 'packed-refs')
# reread cached refs from disk, while holding the lock
f = GitFile(filename, 'wb')
try:
self._packed_refs = None
self.get_packed_refs()
if name not in self._packed_refs:
return
del self._packed_refs[name]
if name in self._peeled_refs:
del self._peeled_refs[name]
write_packed_refs(f, self._packed_refs, self._peeled_refs)
f.close()
finally:
f.abort()
def set_if_equals(self, name, old_ref, new_ref):
"""Set a refname to new_ref only if it currently equals old_ref.
This method follows all symbolic references, and can be used to perform
an atomic compare-and-swap operation.
:param name: The refname to set.
:param old_ref: The old sha the refname must refer to, or None to set
unconditionally.
:param new_ref: The new sha the refname will refer to.
:return: True if the set was successful, False otherwise.
"""
try:
realname, _ = self._follow(name)
except KeyError:
realname = name
filename = self.refpath(realname)
ensure_dir_exists(os.path.dirname(filename))
f = GitFile(filename, 'wb')
try:
if old_ref is not None:
try:
# read again while holding the lock
orig_ref = self.read_loose_ref(realname)
if orig_ref is None:
orig_ref = self.get_packed_refs().get(realname, None)
if orig_ref != old_ref:
f.abort()
return False
except (OSError, IOError):
f.abort()
raise
try:
f.write(new_ref+"\n")
except (OSError, IOError):
f.abort()
raise
finally:
f.close()
return True
def set_if_equals(self, name, old_ref, new_ref):
"""Set a refname to new_ref only if it currently equals old_ref.
This method follows all symbolic references, and can be used to perform
an atomic compare-and-swap operation.
:param name: The refname to set.
:param old_ref: The old sha the refname must refer to, or None to set
unconditionally.
:param new_ref: The new sha the refname will refer to.
:return: True if the set was successful, False otherwise.
"""
try:
realname, _ = self._follow(name)
except KeyError:
realname = name
filename = self.refpath(realname)
ensure_dir_exists(os.path.dirname(filename))
f = GitFile(filename, 'wb')
try:
if old_ref is not None:
try:
# read again while holding the lock
orig_ref = self.read_loose_ref(realname)
if orig_ref is None:
orig_ref = self.get_packed_refs().get(realname, None)
if orig_ref != old_ref:
f.abort()
return False
except (OSError, IOError):
f.abort()
raise
try:
f.write(new_ref + "\n")
except (OSError, IOError):
f.abort()
raise
finally:
f.close()
return True
