# HG changeset patch # User Boris Feld <boris.f...@octobus.net> # Date 1542725358 0 # Tue Nov 20 14:49:18 2018 +0000 # Node ID b6fff7b07488608fe8ea86ffb69a74037ed15cbe # Parent 4369c00a8ee168565fba97112283bbc00be8ce44 # EXP-Topic sparse-perf # Available At https://bitbucket.org/octobus/mercurial-devel/ # hg pull https://bitbucket.org/octobus/mercurial-devel/ -r b6fff7b07488 sparse-revlog: add a `index_get_start` 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 @@ -185,6 +185,39 @@ static inline int index_get_parents(inde return 0; } +static inline int64_t index_get_start(indexObject *self, Py_ssize_t rev) +{ + uint64_t offset; + if (rev >= self->length) { + PyObject *tuple; + PyObject *pylong; + PY_LONG_LONG tmp; + tuple = PyList_GET_ITEM(self->added, rev - self->length); + pylong = PyTuple_GET_ITEM(tuple, 0); + tmp = PyLong_AsLongLong(pylong); + if (tmp == -1 && PyErr_Occurred()) { + return -1; + } + if (tmp < 0) { + PyErr_Format(PyExc_OverflowError, + "revlog entry size out of bound (%llu)", + (unsigned long long)tmp); + return -1; + } + offset = (uint64_t)tmp; + } else { + const char *data = index_deref(self, rev); + offset = getbe32(data + 4); + if (rev == 0) /* mask out version number for the first entry */ + offset &= 0xFFFF; + else { + uint32_t offset_high = getbe32(data); + offset |= ((uint64_t)offset_high) << 32; + } + } + return (int64_t)(offset >> 16); +} + /* * RevlogNG format (all in big endian, data may be inlined): * 6 bytes: offset _______________________________________________ Mercurial-devel mailing list Mercurial-devel@mercurial-scm.org https://www.mercurial-scm.org/mailman/listinfo/mercurial-devel