Mercurial > public > mercurial-scm > hg-stable

comparison mercurial/diffhelpers.c @ 4897:4574925db5c0

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Add Chris Mason's mpatch library. The original repo is http://oss.oracle.com/mercurial/mason/mpatch
author Bryan O'Sullivan <bos@serpentine.com>
date Tue, 17 Jul 2007 09:39:30 -0700
parents
children ec2cc1dadbf7
comparison
equal deleted inserted replaced
4896:ee04732fe61d 4897:4574925db5c0
1 /*
2 * diffhelpers.c - helper routines for mpatch
3 *
4 * Copyright 2007 Chris Mason <chris.mason@oracle.com>
5 *
6 * This software may be used and distributed according to the terms
7 * of the GNU General Public License v2, incorporated herein by reference.
8 */
9
10 #include <Python.h>
11 #include <stdlib.h>
12 #include <string.h>
13
14 static char diffhelpers_doc[] = "Efficient diff parsing";
15 static PyObject *diffhelpers_Error;
16
17
18 /* fixup the last lines of a and b when the patch has no newline at eof */
19 static void _fix_newline(PyObject *hunk, PyObject *a, PyObject *b)
20 {
21 int hunksz = PyList_Size(hunk);
22 PyObject *s = PyList_GET_ITEM(hunk, hunksz-1);
23 char *l = PyString_AS_STRING(s);
24 int sz = PyString_GET_SIZE(s);
25 int alen = PyList_Size(a);
26 int blen = PyList_Size(b);
27 char c = l[0];
28
29 PyObject *hline = PyString_FromStringAndSize(l, sz-1);
30 if (c == ' ' || c == '+') {
31 PyObject *rline = PyString_FromStringAndSize(l+1, sz-2);
32 PyList_SetItem(b, blen-1, rline);
33 }
34 if (c == ' ' || c == '-') {
35 Py_INCREF(hline);
36 PyList_SetItem(a, alen-1, hline);
37 }
38 PyList_SetItem(hunk, hunksz-1, hline);
39 }
40
41 /* python callable form of _fix_newline */
42 static PyObject *
43 fix_newline(PyObject *self, PyObject *args)
44 {
45 PyObject *hunk, *a, *b;
46 if (!PyArg_ParseTuple(args, "OOO", &hunk, &a, &b))
47 return NULL;
48 _fix_newline(hunk, a, b);
49 return Py_BuildValue("l", 0);
50 }
51
52 /*
53 * read lines from fp into the hunk. The hunk is parsed into two arrays
54 * a and b. a gets the old state of the text, b gets the new state
55 * The control char from the hunk is saved when inserting into a, but not b
56 * (for performance while deleting files)
57 */
58 static PyObject *
59 addlines(PyObject *self, PyObject *args)
60 {
61
62 PyObject *fp, *hunk, *a, *b, *x;
63 int i;
64 int lena, lenb;
65 int num;
66 int todoa, todob;
67 char *s, c;
68 PyObject *l;
69 if (!PyArg_ParseTuple(args, "OOiiOO", &fp, &hunk, &lena, &lenb, &a, &b))
70 return NULL;
71
72 while(1) {
73 todoa = lena - PyList_Size(a);
74 todob = lenb - PyList_Size(b);
75 num = todoa > todob ? todoa : todob;
76 if (num == 0)
77 break;
78 for (i = 0 ; i < num ; i++) {
79 x = PyFile_GetLine(fp, 0);
80 s = PyString_AS_STRING(x);
81 c = *s;
82 if (strcmp(s, "\\ No newline at end of file\n") == 0) {
83 _fix_newline(hunk, a, b);
84 continue;
85 }
86 PyList_Append(hunk, x);
87 if (c == '+') {
88 l = PyString_FromString(s + 1);
89 PyList_Append(b, l);
90 Py_DECREF(l);
91 } else if (c == '-') {
92 PyList_Append(a, x);
93 } else {
94 l = PyString_FromString(s + 1);
95 PyList_Append(b, l);
96 Py_DECREF(l);
97 PyList_Append(a, x);
98 }
99 Py_DECREF(x);
100 }
101 }
102 return Py_BuildValue("l", 0);
103 }
104
105 /*
106 * compare the lines in a with the lines in b. a is assumed to have
107 * a control char at the start of each line, this char is ignored in the
108 * compare
109 */
110 static PyObject *
111 testhunk(PyObject *self, PyObject *args)
112 {
113
114 PyObject *a, *b;
115 long bstart;
116 int alen, blen;
117 int i;
118 char *sa, *sb;
119
120 if (!PyArg_ParseTuple(args, "OOl", &a, &b, &bstart))
121 return NULL;
122 alen = PyList_Size(a);
123 blen = PyList_Size(b);
124 if (alen > blen - bstart) {
125 return Py_BuildValue("l", -1);
126 }
127 for (i = 0 ; i < alen ; i++) {
128 sa = PyString_AS_STRING(PyList_GET_ITEM(a, i));
129 sb = PyString_AS_STRING(PyList_GET_ITEM(b, i + bstart));
130 if (strcmp(sa+1, sb) != 0)
131 return Py_BuildValue("l", -1);
132 }
133 return Py_BuildValue("l", 0);
134 }
135
136 static PyMethodDef methods[] = {
137 {"addlines", addlines, METH_VARARGS, "add lines to a hunk\n"},
138 {"fix_newline", fix_newline, METH_VARARGS, "fixup newline counters\n"},
139 {"testhunk", testhunk, METH_VARARGS, "test lines in a hunk\n"},
140 {NULL, NULL}
141 };
142
143 PyMODINIT_FUNC
144 initdiffhelpers(void)
145 {
146 Py_InitModule3("diffhelpers", methods, diffhelpers_doc);
147 diffhelpers_Error = PyErr_NewException("diffhelpers.diffhelpersError",
148 NULL, NULL);
149 }
150