Mercurial > hg
view mercurial/mpatch_module.c @ 31987:8823daaf4665
obsolescence: add test for the "branch replacement" logic during push, case D2
Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.
The current code for this logic is very basic (eg: issue4354) and was poorly
tested. We have a better implementation coming in the evolve extension fixing
these issues and with more serious tests coverage. In the process of upstreaming
this improved logic, we start with adding the test case that are already passing
with the current implementation. Once they are all in, we'll upstream the better
implementation and the extra test cases.
See inline documentation for details about the test case added in this
changeset.
author | Pierre-Yves David <pierre-yves.david@ens-lyon.org> |
---|---|
date | Thu, 13 Apr 2017 16:27:42 +0200 |
parents | 155f0cc3f813 |
children | 5fc3459d0493 |
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/* mpatch.c - efficient binary patching for Mercurial This implements a patch algorithm that's O(m + nlog n) where m is the size of the output and n is the number of patches. Given a list of binary patches, it unpacks each into a hunk list, then combines the hunk lists with a treewise recursion to form a single hunk list. This hunk list is then applied to the original text. The text (or binary) fragments are copied directly from their source Python objects into a preallocated output string to avoid the allocation of intermediate Python objects. Working memory is about 2x the total number of hunks. Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> This software may be used and distributed according to the terms of the GNU General Public License, incorporated herein by reference. */ #define PY_SSIZE_T_CLEAN #include <Python.h> #include <stdlib.h> #include <string.h> #include "util.h" #include "bitmanipulation.h" #include "compat.h" #include "mpatch.h" static char mpatch_doc[] = "Efficient binary patching."; static PyObject *mpatch_Error; static void setpyerr(int r) { switch (r) { case MPATCH_ERR_NO_MEM: PyErr_NoMemory(); break; case MPATCH_ERR_CANNOT_BE_DECODED: PyErr_SetString(mpatch_Error, "patch cannot be decoded"); break; case MPATCH_ERR_INVALID_PATCH: PyErr_SetString(mpatch_Error, "invalid patch"); break; } } struct mpatch_flist *cpygetitem(void *bins, ssize_t pos) { const char *buffer; struct mpatch_flist *res; ssize_t blen; int r; PyObject *tmp = PyList_GetItem((PyObject*)bins, pos); if (!tmp) return NULL; if (PyObject_AsCharBuffer(tmp, &buffer, (Py_ssize_t*)&blen)) return NULL; if ((r = mpatch_decode(buffer, blen, &res)) < 0) { if (!PyErr_Occurred()) setpyerr(r); return NULL; } return res; } static PyObject * patches(PyObject *self, PyObject *args) { PyObject *text, *bins, *result; struct mpatch_flist *patch; const char *in; int r = 0; char *out; Py_ssize_t len, outlen, inlen; if (!PyArg_ParseTuple(args, "OO:mpatch", &text, &bins)) return NULL; len = PyList_Size(bins); if (!len) { /* nothing to do */ Py_INCREF(text); return text; } if (PyObject_AsCharBuffer(text, &in, &inlen)) return NULL; patch = mpatch_fold(bins, cpygetitem, 0, len); if (!patch) { /* error already set or memory error */ if (!PyErr_Occurred()) PyErr_NoMemory(); return NULL; } outlen = mpatch_calcsize(inlen, patch); if (outlen < 0) { r = (int)outlen; result = NULL; goto cleanup; } result = PyBytes_FromStringAndSize(NULL, outlen); if (!result) { result = NULL; goto cleanup; } out = PyBytes_AsString(result); if ((r = mpatch_apply(out, in, inlen, patch)) < 0) { Py_DECREF(result); result = NULL; } cleanup: mpatch_lfree(patch); if (!result && !PyErr_Occurred()) setpyerr(r); return result; } /* calculate size of a patched file directly */ static PyObject * patchedsize(PyObject *self, PyObject *args) { long orig, start, end, len, outlen = 0, last = 0, pos = 0; Py_ssize_t patchlen; char *bin; if (!PyArg_ParseTuple(args, "ls#", &orig, &bin, &patchlen)) return NULL; while (pos >= 0 && pos < patchlen) { start = getbe32(bin + pos); end = getbe32(bin + pos + 4); len = getbe32(bin + pos + 8); if (start > end) break; /* sanity check */ pos += 12 + len; outlen += start - last; last = end; outlen += len; } if (pos != patchlen) { if (!PyErr_Occurred()) PyErr_SetString(mpatch_Error, "patch cannot be decoded"); return NULL; } outlen += orig - last; return Py_BuildValue("l", outlen); } static PyMethodDef methods[] = { {"patches", patches, METH_VARARGS, "apply a series of patches\n"}, {"patchedsize", patchedsize, METH_VARARGS, "calculed patched size\n"}, {NULL, NULL} }; #ifdef IS_PY3K static struct PyModuleDef mpatch_module = { PyModuleDef_HEAD_INIT, "mpatch", mpatch_doc, -1, methods }; PyMODINIT_FUNC PyInit_mpatch(void) { PyObject *m; m = PyModule_Create(&mpatch_module); if (m == NULL) return NULL; mpatch_Error = PyErr_NewException("mercurial.mpatch.mpatchError", NULL, NULL); Py_INCREF(mpatch_Error); PyModule_AddObject(m, "mpatchError", mpatch_Error); return m; } #else PyMODINIT_FUNC initmpatch(void) { Py_InitModule3("mpatch", methods, mpatch_doc); mpatch_Error = PyErr_NewException("mercurial.mpatch.mpatchError", NULL, NULL); } #endif