--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/bdiff_module.c Wed Jul 13 10:46:26 2016 +0200
@@ -0,0 +1,203 @@
+/*
+ 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"
+
+
+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;
+ PyObject *result = NULL;
+ struct bdiff_line *al, *bl;
+ struct bdiff_hunk l, *h;
+ int an, bn, count;
+ Py_ssize_t len = 0, la, lb;
+ 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();
+ an = bdiff_splitlines(sa, la, &al);
+ bn = bdiff_splitlines(sb, lb, &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 - al->l), rb);
+ putbe32((uint32_t)(al[h->a1].l - 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 *)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:
+ 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