changeset 29693:b9b9f9a92481

mpatch: split mpatch into two files
author Maciej Fijalkowski <fijall@gmail.com>
date Mon, 18 Jul 2016 19:02:30 +0200
parents 6b3a8d034b69
children 55dd12204b8e
files mercurial/mpatch.c mercurial/mpatch.h mercurial/mpatch_module.c setup.py
diffstat 4 files changed, 181 insertions(+), 125 deletions(-) [+]
line wrap: on
line diff
--- a/mercurial/mpatch.c	Mon Jul 18 16:25:14 2016 +0200
+++ b/mercurial/mpatch.c	Mon Jul 18 19:02:30 2016 +0200
@@ -41,7 +41,7 @@
 	struct mpatch_frag *base, *head, *tail;
 };
 
-static struct mpatch_flist *lalloc(ssize_t size)
+struct mpatch_flist *lalloc(ssize_t size)
 {
 	struct mpatch_flist *a = NULL;
 
@@ -63,7 +63,7 @@
 	return NULL;
 }
 
-static void mpatch_lfree(struct mpatch_flist *a)
+void mpatch_lfree(struct mpatch_flist *a)
 {
 	if (a) {
 		free(a->base);
@@ -202,7 +202,7 @@
 }
 
 /* decode a binary patch into a hunk list */
-static struct mpatch_flist *mpatch_decode(const char *bin, ssize_t len)
+struct mpatch_flist *mpatch_decode(const char *bin, ssize_t len)
 {
 	struct mpatch_flist *l;
 	struct mpatch_frag *lt;
@@ -238,7 +238,7 @@
 }
 
 /* calculate the size of resultant text */
-static ssize_t mpatch_calcsize(ssize_t len, struct mpatch_flist *l)
+ssize_t mpatch_calcsize(ssize_t len, struct mpatch_flist *l)
 {
 	ssize_t outlen = 0, last = 0;
 	struct mpatch_frag *f = l->head;
@@ -260,7 +260,7 @@
 	return outlen;
 }
 
-static int mpatch_apply(char *buf, const char *orig, ssize_t len,
+int mpatch_apply(char *buf, const char *orig, ssize_t len,
 	struct mpatch_flist *l)
 {
 	struct mpatch_frag *f = l->head;
@@ -286,7 +286,7 @@
 }
 
 /* recursively generate a patch of all bins between start and end */
-static struct mpatch_flist *mpatch_fold(PyObject *bins, ssize_t start,
+struct mpatch_flist *mpatch_fold(PyObject *bins, ssize_t start,
 	ssize_t end)
 {
 	ssize_t len, blen;
@@ -308,121 +308,3 @@
 		       mpatch_fold(bins, start + len, end));
 }
 
-static PyObject *
-patches(PyObject *self, PyObject *args)
-{
-	PyObject *text, *bins, *result;
-	struct mpatch_flist *patch;
-	const char *in;
-	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, 0, len);
-	if (!patch)
-		return NULL;
-
-	outlen = mpatch_calcsize(inlen, patch);
-	if (outlen < 0) {
-		result = NULL;
-		goto cleanup;
-	}
-	result = PyBytes_FromStringAndSize(NULL, outlen);
-	if (!result) {
-		result = NULL;
-		goto cleanup;
-	}
-	out = PyBytes_AsString(result);
-	if (!mpatch_apply(out, in, inlen, patch)) {
-		Py_DECREF(result);
-		result = NULL;
-	}
-cleanup:
-	mpatch_lfree(patch);
-	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
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/mpatch.h	Mon Jul 18 19:02:30 2016 +0200
@@ -0,0 +1,20 @@
+#ifndef _HG_MPATCH_H_
+#define _HG_MPATCH_H_
+
+struct mpatch_frag {
+	int start, end, len;
+	const char *data;
+};
+
+struct mpatch_flist {
+	struct mpatch_frag *base, *head, *tail;
+};
+
+int mpatch_decode(const char *bin, ssize_t len, struct mpatch_flist** res);
+ssize_t mpatch_calcsize(ssize_t len, struct mpatch_flist *l);
+void mpatch_lfree(struct mpatch_flist *a);
+int mpatch_apply(char *buf, const char *orig, ssize_t len,
+	struct mpatch_flist *l);
+struct mpatch_flist *mpatch_fold(void *bins, ssize_t start, ssize_t end);
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/mpatch_module.c	Mon Jul 18 19:02:30 2016 +0200
@@ -0,0 +1,153 @@
+/*
+ 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 PyObject *
+patches(PyObject *self, PyObject *args)
+{
+	PyObject *text, *bins, *result;
+	struct mpatch_flist *patch;
+	const char *in;
+	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, 0, len);
+	if (!patch)
+		return NULL;
+
+	outlen = mpatch_calcsize(inlen, patch);
+	if (outlen < 0) {
+		result = NULL;
+		goto cleanup;
+	}
+	result = PyBytes_FromStringAndSize(NULL, outlen);
+	if (!result) {
+		result = NULL;
+		goto cleanup;
+	}
+	out = PyBytes_AsString(result);
+	if (!mpatch_apply(out, in, inlen, patch)) {
+		Py_DECREF(result);
+		result = NULL;
+	}
+cleanup:
+	mpatch_lfree(patch);
+	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
--- a/setup.py	Mon Jul 18 16:25:14 2016 +0200
+++ b/setup.py	Mon Jul 18 19:02:30 2016 +0200
@@ -561,7 +561,8 @@
               depends=common_depends + ['mercurial/bdiff.h']),
     Extension('mercurial.diffhelpers', ['mercurial/diffhelpers.c'],
               depends=common_depends),
-    Extension('mercurial.mpatch', ['mercurial/mpatch.c'],
+    Extension('mercurial.mpatch', ['mercurial/mpatch.c',
+                                   'mercurial/mpatch_module.c'],
               depends=common_depends),
     Extension('mercurial.parsers', ['mercurial/dirs.c',
                                     'mercurial/manifest.c',