Mercurial > hg
diff mercurial/cext/bdiff.c @ 32369:3b88a7fa97d8
bdiff: switch to policy importer
# no-check-commit
author | Yuya Nishihara <yuya@tcha.org> |
---|---|
date | Sat, 13 Aug 2016 12:12:50 +0900 |
parents | mercurial/bdiff_module.c@4195b84940e9 |
children | b90e8da190da |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mercurial/cext/bdiff.c Sat Aug 13 12:12:50 2016 +0900 @@ -0,0 +1,220 @@ +/* + bdiff.c - efficient binary diff extension for Mercurial + + 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. + + Based roughly on Python difflib +*/ + +#define PY_SSIZE_T_CLEAN +#include <Python.h> +#include <stdlib.h> +#include <string.h> +#include <limits.h> + +#include "bdiff.h" +#include "bitmanipulation.h" +#include "util.h" + + +static PyObject *blocks(PyObject *self, PyObject *args) +{ + PyObject *sa, *sb, *rl = NULL, *m; + struct bdiff_line *a, *b; + struct bdiff_hunk l, *h; + int an, bn, count, pos = 0; + + l.next = NULL; + + if (!PyArg_ParseTuple(args, "SS:bdiff", &sa, &sb)) + return NULL; + + an = bdiff_splitlines(PyBytes_AsString(sa), PyBytes_Size(sa), &a); + bn = bdiff_splitlines(PyBytes_AsString(sb), PyBytes_Size(sb), &b); + + if (!a || !b) + goto nomem; + + count = bdiff_diff(a, an, b, bn, &l); + if (count < 0) + goto nomem; + + rl = PyList_New(count); + if (!rl) + goto nomem; + + for (h = l.next; h; h = h->next) { + m = Py_BuildValue("iiii", h->a1, h->a2, h->b1, h->b2); + PyList_SetItem(rl, pos, m); + pos++; + } + +nomem: + free(a); + free(b); + bdiff_freehunks(l.next); + return rl ? rl : PyErr_NoMemory(); +} + +static PyObject *bdiff(PyObject *self, PyObject *args) +{ + char *sa, *sb, *rb, *ia, *ib; + PyObject *result = NULL; + struct bdiff_line *al, *bl; + struct bdiff_hunk l, *h; + int an, bn, count; + Py_ssize_t len = 0, la, lb, li = 0, lcommon = 0, lmax; + PyThreadState *_save; + + l.next = NULL; + + if (!PyArg_ParseTuple(args, "s#s#:bdiff", &sa, &la, &sb, &lb)) + return NULL; + + if (la > UINT_MAX || lb > UINT_MAX) { + PyErr_SetString(PyExc_ValueError, "bdiff inputs too large"); + return NULL; + } + + _save = PyEval_SaveThread(); + + lmax = la > lb ? lb : la; + for (ia = sa, ib = sb; + li < lmax && *ia == *ib; + ++li, ++ia, ++ib) + if (*ia == '\n') + lcommon = li + 1; + /* we can almost add: if (li == lmax) lcommon = li; */ + + an = bdiff_splitlines(sa + lcommon, la - lcommon, &al); + bn = bdiff_splitlines(sb + lcommon, lb - lcommon, &bl); + if (!al || !bl) + goto nomem; + + count = bdiff_diff(al, an, bl, bn, &l); + if (count < 0) + goto nomem; + + /* calculate length of output */ + la = lb = 0; + for (h = l.next; h; h = h->next) { + if (h->a1 != la || h->b1 != lb) + len += 12 + bl[h->b1].l - bl[lb].l; + la = h->a2; + lb = h->b2; + } + PyEval_RestoreThread(_save); + _save = NULL; + + result = PyBytes_FromStringAndSize(NULL, len); + + if (!result) + goto nomem; + + /* build binary patch */ + rb = PyBytes_AsString(result); + la = lb = 0; + + for (h = l.next; h; h = h->next) { + if (h->a1 != la || h->b1 != lb) { + len = bl[h->b1].l - bl[lb].l; + putbe32((uint32_t)(al[la].l + lcommon - al->l), rb); + putbe32((uint32_t)(al[h->a1].l + lcommon - al->l), rb + 4); + putbe32((uint32_t)len, rb + 8); + memcpy(rb + 12, bl[lb].l, len); + rb += 12 + len; + } + la = h->a2; + lb = h->b2; + } + +nomem: + if (_save) + PyEval_RestoreThread(_save); + free(al); + free(bl); + bdiff_freehunks(l.next); + return result ? result : PyErr_NoMemory(); +} + +/* + * If allws != 0, remove all whitespace (' ', \t and \r). Otherwise, + * reduce whitespace sequences to a single space and trim remaining whitespace + * from end of lines. + */ +static PyObject *fixws(PyObject *self, PyObject *args) +{ + PyObject *s, *result = NULL; + char allws, c; + const char *r; + Py_ssize_t i, rlen, wlen = 0; + char *w; + + if (!PyArg_ParseTuple(args, "Sb:fixws", &s, &allws)) + return NULL; + r = PyBytes_AsString(s); + rlen = PyBytes_Size(s); + + w = (char *)PyMem_Malloc(rlen ? rlen : 1); + if (!w) + goto nomem; + + for (i = 0; i != rlen; i++) { + c = r[i]; + if (c == ' ' || c == '\t' || c == '\r') { + if (!allws && (wlen == 0 || w[wlen - 1] != ' ')) + w[wlen++] = ' '; + } else if (c == '\n' && !allws + && wlen > 0 && w[wlen - 1] == ' ') { + w[wlen - 1] = '\n'; + } else { + w[wlen++] = c; + } + } + + result = PyBytes_FromStringAndSize(w, wlen); + +nomem: + PyMem_Free(w); + return result ? result : PyErr_NoMemory(); +} + + +static char mdiff_doc[] = "Efficient binary diff."; + +static PyMethodDef methods[] = { + {"bdiff", bdiff, METH_VARARGS, "calculate a binary diff\n"}, + {"blocks", blocks, METH_VARARGS, "find a list of matching lines\n"}, + {"fixws", fixws, METH_VARARGS, "normalize diff whitespaces\n"}, + {NULL, NULL} +}; + +static const int version = 1; + +#ifdef IS_PY3K +static struct PyModuleDef bdiff_module = { + PyModuleDef_HEAD_INIT, + "bdiff", + mdiff_doc, + -1, + methods +}; + +PyMODINIT_FUNC PyInit_bdiff(void) +{ + PyObject *m; + m = PyModule_Create(&bdiff_module); + PyModule_AddIntConstant(m, "version", version); + return m; +} +#else +PyMODINIT_FUNC initbdiff(void) +{ + PyObject *m; + m = Py_InitModule3("bdiff", methods, mdiff_doc); + PyModule_AddIntConstant(m, "version", version); +} +#endif