view mercurial/diffhelpers.c @ 9410:1c83938b6a8e

extensions: load and configure extensions in well-defined phases

Extensions are now loaded with a call-graph like this:

  dispatch._dispatch
      extensions.loadall
          extensions.load
                # add foo module to extensions._extensions
          extensions.load
                # add bar module to extensions._extensions

          foo.uisetup(ui)
          bar.uisetup(ui)

      foo.extsetup()
      bar.extsetup()

      commands.table.update(foo.cmdtable)
      commands.table.update(bar.cmdtable)

  hg.repository
      foo.reposetup(ui, repo)
      bar.reposetup(ui, repo)

The uisetup calls could easily be moved out to dispatch._dispatch, but
have been kept in extensions.loadall since at least TortoiseHg calls
extensions.loadall and expects it to call uisetup.

The extensions.load function called uisetup. It now has an unused ui
argument which has been kept for backwards compatibility.

/*
 * diffhelpers.c - helper routines for mpatch
 *
 * Copyright 2007 Chris Mason <[e-mail]>
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License v2, incorporated herein by reference.
 */

#include <Python.h>
#include <stdlib.h>
#include <string.h>

static char diffhelpers_doc[] = "Efficient diff parsing";
static PyObject *diffhelpers_Error;


/* fixup the last lines of a and b when the patch has no newline at eof */
static void _fix_newline(PyObject *hunk, PyObject *a, PyObject *b)
{
	int hunksz = PyList_Size(hunk);
	PyObject *s = PyList_GET_ITEM(hunk, hunksz-1);
	char *l = PyString_AS_STRING(s);
	int sz = PyString_GET_SIZE(s);
	int alen = PyList_Size(a);
	int blen = PyList_Size(b);
	char c = l[0];

	PyObject *hline = PyString_FromStringAndSize(l, sz-1);
	if (c == ' ' || c == '+') {
		PyObject *rline = PyString_FromStringAndSize(l+1, sz-2);
		PyList_SetItem(b, blen-1, rline);
	}
	if (c == ' ' || c == '-') {
		Py_INCREF(hline);
		PyList_SetItem(a, alen-1, hline);
	}
	PyList_SetItem(hunk, hunksz-1, hline);
}

/* python callable form of _fix_newline */
static PyObject *
fix_newline(PyObject *self, PyObject *args)
{
	PyObject *hunk, *a, *b;
	if (!PyArg_ParseTuple(args, "OOO", &hunk, &a, &b))
		return NULL;
	_fix_newline(hunk, a, b);
	return Py_BuildValue("l", 0);
}

/*
 * read lines from fp into the hunk.  The hunk is parsed into two arrays
 * a and b.  a gets the old state of the text, b gets the new state
 * The control char from the hunk is saved when inserting into a, but not b
 * (for performance while deleting files)
 */
static PyObject *
addlines(PyObject *self, PyObject *args)
{

	PyObject *fp, *hunk, *a, *b, *x;
	int i;
	int lena, lenb;
	int num;
	int todoa, todob;
	char *s, c;
	PyObject *l;
	if (!PyArg_ParseTuple(args, "OOiiOO", &fp, &hunk, &lena, &lenb, &a, &b))
		return NULL;

	while(1) {
		todoa = lena - PyList_Size(a);
		todob = lenb - PyList_Size(b);
		num = todoa > todob ? todoa : todob;
		if (num == 0)
		    break;
		for (i = 0 ; i < num ; i++) {
			x = PyFile_GetLine(fp, 0);
			s = PyString_AS_STRING(x);
			c = *s;
			if (strcmp(s, "\\ No newline at end of file\n") == 0) {
				_fix_newline(hunk, a, b);
				continue;
			}
			if (c == '\n') {
				/* Some patches may be missing the control char
				 * on empty lines. Supply a leading space. */
				Py_DECREF(x);
				x = PyString_FromString(" \n");
			}
			PyList_Append(hunk, x);
			if (c == '+') {
				l = PyString_FromString(s + 1);
				PyList_Append(b, l);
				Py_DECREF(l);
			} else if (c == '-') {
				PyList_Append(a, x);
			} else {
				l = PyString_FromString(s + 1);
				PyList_Append(b, l);
				Py_DECREF(l);
				PyList_Append(a, x);
			}
			Py_DECREF(x);
		}
	}
	return Py_BuildValue("l", 0);
}

/*
 * compare the lines in a with the lines in b.  a is assumed to have
 * a control char at the start of each line, this char is ignored in the
 * compare
 */
static PyObject *
testhunk(PyObject *self, PyObject *args)
{

	PyObject *a, *b;
	long bstart;
	int alen, blen;
	int i;
	char *sa, *sb;

	if (!PyArg_ParseTuple(args, "OOl", &a, &b, &bstart))
		return NULL;
	alen = PyList_Size(a);
	blen = PyList_Size(b);
	if (alen > blen - bstart) {
		return Py_BuildValue("l", -1);
	}
	for (i = 0 ; i < alen ; i++) {
		sa = PyString_AS_STRING(PyList_GET_ITEM(a, i));
		sb = PyString_AS_STRING(PyList_GET_ITEM(b, i + bstart));
		if (strcmp(sa+1, sb) != 0)
			return Py_BuildValue("l", -1);
	}
	return Py_BuildValue("l", 0);
}

static PyMethodDef methods[] = {
	{"addlines", addlines, METH_VARARGS, "add lines to a hunk\n"},
	{"fix_newline", fix_newline, METH_VARARGS, "fixup newline counters\n"},
	{"testhunk", testhunk, METH_VARARGS, "test lines in a hunk\n"},
	{NULL, NULL}
};

PyMODINIT_FUNC
initdiffhelpers(void)
{
	Py_InitModule3("diffhelpers", methods, diffhelpers_doc);
	diffhelpers_Error = PyErr_NewException("diffhelpers.diffhelpersError",
	                                        NULL, NULL);
}