| Submitter | Boris Feld |
|---|---|
| Date | Nov. 20, 2018, 8:44 p.m. |
| Message ID | <8863dc1f7d078827708d.1542746673@localhost.localdomain> |
| Download | mbox | patch |
| Permalink | /patch/36679/ |
| State | Superseded |
| Headers | show |
Comments
On Tue, 20 Nov 2018 21:44:33 +0100, Boris Feld wrote: > # HG changeset patch > # User Boris Feld <boris.feld@octobus.net> > # Date 1541785378 -3600 > # Fri Nov 09 18:42:58 2018 +0100 > # Node ID 8863dc1f7d078827708d178bbbfee5519b4c9b0f > # Parent 60a55da39befa4996c1a88ca6f663765ea143ef2 > # EXP-Topic sparse-perf > # Available At https://bitbucket.org/octobus/mercurial-devel/ > # hg pull https://bitbucket.org/octobus/mercurial-devel/ -r 8863dc1f7d07 > sparse-revlog: add a `index_get_length` function in C > > We are about to implement a native version of `slicechunktodensity`. For > clarity, we introduce the helper functions first. This new function provides > an efficient way to retrieve some of the information needed by > `slicechunktodensity`. > > diff --git a/mercurial/cext/revlog.c b/mercurial/cext/revlog.c > --- a/mercurial/cext/revlog.c > +++ b/mercurial/cext/revlog.c > @@ -225,6 +225,44 @@ static inline int64_t index_get_start(in > return (int64_t)(offset >> 16); > } > > +static inline int index_get_length(indexObject *self, Py_ssize_t rev) > +{ > + if (rev >= self->length) { > + PyObject *tuple; > + PyObject *pylong; > + unsigned PY_LONG_LONG tmp; > + tuple = PyList_GET_ITEM(self->added, rev - self->length); > + pylong = PyTuple_GET_ITEM(tuple, 1); > +#ifndef IS_PY3K > + if (PyInt_Check(pylong)) { > + long tmp2 = PyInt_AsLong(pylong); > + if (tmp2 < 0) { > + return -1; Nit: exception wouldn't be set if the value was actually -1. > + } > + tmp = (unsigned PY_LONG_LONG)tmp2; > + } else { > +#endif > + tmp = PyLong_AsUnsignedLongLong(pylong); > + if (tmp == (unsigned PY_LONG_LONG) - 1) { > + return -1; > + } IIUC, we can simply use PyInt_AsLong() here since a valid length should be in int range. PyInt_AsLong is aliased to PyLong_AsLong on Python 3. To be clear, what I have in mind is something like this: long ret = PyInt_AsLong(PyTuple_GET_ITEM(tuple, 1)); if (ret == -1 && PyErr_Occurred()) return -1; if (ret < 0 || ret > (long)INT_MAX) set overflow error and return -1; > + if (tmp > INT_MAX) { > + PyErr_Format(PyExc_OverflowError, > + "revlog entry size too large (%llu)", > + (long long)tmp); > + return -1; > + } > + return (int)tmp;
Patch
diff --git a/mercurial/cext/revlog.c b/mercurial/cext/revlog.c --- a/mercurial/cext/revlog.c +++ b/mercurial/cext/revlog.c @@ -225,6 +225,44 @@ static inline int64_t index_get_start(in return (int64_t)(offset >> 16); } +static inline int index_get_length(indexObject *self, Py_ssize_t rev) +{ + if (rev >= self->length) { + PyObject *tuple; + PyObject *pylong; + unsigned PY_LONG_LONG tmp; + tuple = PyList_GET_ITEM(self->added, rev - self->length); + pylong = PyTuple_GET_ITEM(tuple, 1); +#ifndef IS_PY3K + if (PyInt_Check(pylong)) { + long tmp2 = PyInt_AsLong(pylong); + if (tmp2 < 0) { + return -1; + } + tmp = (unsigned PY_LONG_LONG)tmp2; + } else { +#endif + tmp = PyLong_AsUnsignedLongLong(pylong); + if (tmp == (unsigned PY_LONG_LONG) - 1) { + return -1; + } + +#ifndef IS_PY3K + } +#endif + if (tmp > INT_MAX) { + PyErr_Format(PyExc_OverflowError, + "revlog entry size too large (%llu)", + (long long)tmp); + return -1; + } + return (int)tmp; + } else { + const char *data = index_deref(self, rev); + return (int)getbe32(data + 8); + } +} + /* * RevlogNG format (all in big endian, data may be inlined): * 6 bytes: offset