Avoid extra filelogs entries.
Right now, there are some situations in which localrepo.filecommit can
create filelog entries even though they're not needed. For example:
- permissions for a file have changed;
- qrefresh can create a filelog entry identical to its parent (see the
added test);
- convert-repo creates extra filelog entries in every merge where the
first parent has added files (for example, changeset ebebe9577a1a of
the kernel repo added extra filelog entries to files in the
arch/blackfin directory, even though the merge should only touch the
drivers/ata directory). This makes "hg log file" in a converted repo
less useful than it could be, since it may mention many merges that
don't actually touch that specific file.
They all come from the same basic problem: localrepo.commit (through
filecommit) creates new filelog entries for all files passed to it
(except for some cases during a merge).
Patch and test case provided by Benoit.
This should fix issue351.
/*
base85 codec
Copyright 2006 Brendan Cully <brendan@kublai.com>
This software may be used and distributed according to the terms of
the GNU General Public License, incorporated herein by reference.
Largely based on git's implementation
*/
#include <Python.h>
static const char b85chars[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{|}~";
static char b85dec[256];
static void
b85prep(void)
{
int i;
memset(b85dec, 0, sizeof(b85dec));
for (i = 0; i < sizeof(b85chars); i++)
b85dec[(int)(b85chars[i])] = i + 1;
}
static PyObject *
b85encode(PyObject *self, PyObject *args)
{
const unsigned char *text;
PyObject *out;
char *dst;
int len, olen, i;
unsigned int acc, val, ch;
int pad = 0;
if (!PyArg_ParseTuple(args, "s#|i", &text, &len, &pad))
return NULL;
if (pad)
olen = ((len + 3) / 4 * 5) - 3;
else {
olen = len % 4;
if (olen)
olen++;
olen += len / 4 * 5;
}
if (!(out = PyString_FromStringAndSize(NULL, olen + 3)))
return NULL;
dst = PyString_AS_STRING(out);
while (len) {
acc = 0;
for (i = 24; i >= 0; i -= 8) {
ch = *text++;
acc |= ch << i;
if (--len == 0)
break;
}
for (i = 4; i >= 0; i--) {
val = acc % 85;
acc /= 85;
dst[i] = b85chars[val];
}
dst += 5;
}
if (!pad)
_PyString_Resize(&out, olen);
return out;
}
static PyObject *
b85decode(PyObject *self, PyObject *args)
{
PyObject *out;
const char *text;
char *dst;
int len, i, j, olen, c, cap;
unsigned int acc;
if (!PyArg_ParseTuple(args, "s#", &text, &len))
return NULL;
olen = len / 5 * 4;
i = len % 5;
if (i)
olen += i - 1;
if (!(out = PyString_FromStringAndSize(NULL, olen)))
return NULL;
dst = PyString_AS_STRING(out);
i = 0;
while (i < len)
{
acc = 0;
cap = len - i - 1;
if (cap > 4)
cap = 4;
for (j = 0; j < cap; i++, j++)
{
c = b85dec[(int)*text++] - 1;
if (c < 0)
return PyErr_Format(PyExc_ValueError, "Bad base85 character at position %d", i);
acc = acc * 85 + c;
}
if (i++ < len)
{
c = b85dec[(int)*text++] - 1;
if (c < 0)
return PyErr_Format(PyExc_ValueError, "Bad base85 character at position %d", i);
/* overflow detection: 0xffffffff == "|NsC0",
* "|NsC" == 0x03030303 */
if (acc > 0x03030303 || (acc *= 85) > 0xffffffff - c)
return PyErr_Format(PyExc_ValueError, "Bad base85 sequence at position %d", i);
acc += c;
}
cap = olen < 4 ? olen : 4;
olen -= cap;
for (j = 0; j < 4 - cap; j++)
acc *= 85;
if (cap && cap < 4)
acc += 0xffffff >> (cap - 1) * 8;
for (j = 0; j < cap; j++)
{
acc = (acc << 8) | (acc >> 24);
*dst++ = acc;
}
}
return out;
}
static char base85_doc[] = "Base85 Data Encoding";
static PyMethodDef methods[] = {
{"b85encode", b85encode, METH_VARARGS,
"Encode text in base85.\n\n"
"If the second parameter is true, pad the result to a multiple of "
"five characters.\n"},
{"b85decode", b85decode, METH_VARARGS, "Decode base85 text.\n"},
{NULL, NULL}
};
PyMODINIT_FUNC initbase85(void)
{
Py_InitModule3("base85", methods, base85_doc);
b85prep();
}