Mercurial > hg
view mercurial/bdiff_module.c @ 31807:e6eb86b154c5
templater: provide loop counter as "index" keyword
This was originally written for JSON templating where we would have to be
careful to not add extra comma, but seems generally useful.
Inner loop started by % operator has its own counter.
author | Yuya Nishihara <yuya@tcha.org> |
---|---|
date | Fri, 22 Apr 2016 21:46:33 +0900 |
parents | 08ecec297521 |
children | 4195b84940e9 |
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/* 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} }; #ifdef IS_PY3K static struct PyModuleDef bdiff_module = { PyModuleDef_HEAD_INIT, "bdiff", mdiff_doc, -1, methods }; PyMODINIT_FUNC PyInit_bdiff(void) { return PyModule_Create(&bdiff_module); } #else PyMODINIT_FUNC initbdiff(void) { Py_InitModule3("bdiff", methods, mdiff_doc); } #endif