dulwich/_objects.c

   1 /*
   2  * Copyright (C) 2009 Jelmer Vernooij <jelmer@samba.org>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; version 2
   7  * of the License or (at your option) a later version of the License.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  17  * MA  02110-1301, USA.
  18  */
  19
  20 #include <Python.h>
  21 #include <stdlib.h>
  22 #include <sys/stat.h>
  23
  24 #define bytehex(x) (((x)<0xa)?('0'+(x)):('a'-0xa+(x)))
  25
  26 static PyObject *sha_to_pyhex(const unsigned char *sha)
  27 {
  28         char hexsha[41];
  29         int i;
  30         for (i = 0; i < 20; i++) {
  31                 hexsha[i*2] = bytehex((sha[i] & 0xF0) >> 4);
  32                 hexsha[i*2+1] = bytehex(sha[i] & 0x0F);
  33         }
  34
  35         return PyString_FromStringAndSize(hexsha, 40);
  36 }
  37
  38 static PyObject *py_parse_tree(PyObject *self, PyObject *args)
  39 {
  40         char *text, *end;
  41         int len, namelen;
  42         PyObject *ret, *item, *name;
  43
  44         if (!PyArg_ParseTuple(args, "s#", &text, &len))
  45                 return NULL;
  46
  47         ret = PyDict_New();
  48         if (ret == NULL) {
  49                 return NULL;
  50         }
  51
  52         end = text + len;
  53
  54         while (text < end) {
  55                 long mode;
  56                 mode = strtol(text, &text, 8);
  57
  58                 if (*text != ' ') {
  59                         PyErr_SetString(PyExc_RuntimeError, "Expected space");
  60                         Py_DECREF(ret);
  61                         return NULL;
  62                 }
  63
  64                 text++;
  65
  66                 namelen = strlen(text);
  67
  68                 name = PyString_FromStringAndSize(text, namelen);
  69                 if (name == NULL) {
  70                         Py_DECREF(ret);
  71                         return NULL;
  72                 }
  73
  74                 item = Py_BuildValue("(lN)", mode,
  75                                                          sha_to_pyhex((unsigned char *)text+namelen+1));
  76                 if (item == NULL) {
  77                         Py_DECREF(ret);
  78                         Py_DECREF(name);
  79                         return NULL;
  80                 }
  81                 if (PyDict_SetItem(ret, name, item) == -1) {
  82                         Py_DECREF(ret);
  83                         Py_DECREF(item);
  84                         return NULL;
  85                 }
  86                 Py_DECREF(name);
  87                 Py_DECREF(item);
  88
  89                 text += namelen+21;
  90         }
  91
  92         return ret;
  93 }
  94
  95 struct tree_item {
  96         const char *name;
  97         int mode;
  98         PyObject *tuple;
  99 };
 100
 101 int cmp_tree_item(const void *_a, const void *_b)
 102 {
 103         const struct tree_item *a = _a, *b = _b;
 104         const char *remain_a, *remain_b;
 105         int ret, common;
 106         if (strlen(a->name) > strlen(b->name)) {
 107                 common = strlen(b->name);
 108                 remain_a = a->name + common;
 109                 remain_b = (S_ISDIR(b->mode)?"/":"");
 110         } else if (strlen(b->name) > strlen(a->name)) {
 111                 common = strlen(a->name);
 112                 remain_a = (S_ISDIR(a->mode)?"/":"");
 113                 remain_b = b->name + common;
 114         } else { /* strlen(a->name) == strlen(b->name) */
 115                 common = 0;
 116                 remain_a = a->name;
 117                 remain_b = b->name;
 118         }
 119         ret = strncmp(a->name, b->name, common);
 120         if (ret != 0)
 121                 return ret;
 122         return strcmp(remain_a, remain_b);
 123 }
 124
 125 static PyObject *py_sorted_tree_items(PyObject *self, PyObject *entries)
 126 {
 127         struct tree_item *qsort_entries;
 128         int num, i;
 129         PyObject *ret;
 130         Py_ssize_t pos = 0;
 131         PyObject *key, *value;
 132
 133         if (!PyDict_Check(entries)) {
 134                 PyErr_SetString(PyExc_TypeError, "Argument not a dictionary");
 135                 return NULL;
 136         }
 137
 138         num = PyDict_Size(entries);
 139         qsort_entries = malloc(num * sizeof(struct tree_item));
 140         if (qsort_entries == NULL) {
 141                 PyErr_NoMemory();
 142                 return NULL;
 143         }
 144
 145         i = 0;
 146         while (PyDict_Next(entries, &pos, &key, &value)) {
 147                 PyObject *py_mode, *py_sha;
 148
 149                 if (PyTuple_Size(value) != 2) {
 150                         PyErr_SetString(PyExc_ValueError, "Tuple has invalid size");
 151                         free(qsort_entries);
 152                         return NULL;
 153                 }
 154
 155                 py_mode = PyTuple_GET_ITEM(value, 0);
 156                 py_sha = PyTuple_GET_ITEM(value, 1);
 157                 qsort_entries[i].tuple = Py_BuildValue("(OOO)", key, py_mode, py_sha);
 158                 if (!PyString_CheckExact(key)) {
 159                         PyErr_SetString(PyExc_TypeError, "Name is not a string");
 160                         free(qsort_entries);
 161                         return NULL;
 162                 }
 163                 qsort_entries[i].name = PyString_AS_STRING(key);
 164                 if (!PyInt_CheckExact(py_mode)) {
 165                         PyErr_SetString(PyExc_TypeError, "Mode is not an int");
 166                         free(qsort_entries);
 167                         return NULL;
 168                 }
 169                 qsort_entries[i].mode = PyInt_AS_LONG(py_mode);
 170                 i++;
 171         }
 172
 173         qsort(qsort_entries, num, sizeof(struct tree_item), cmp_tree_item);
 174
 175         ret = PyList_New(num);
 176         if (ret == NULL) {
 177                 free(qsort_entries);
 178                 PyErr_NoMemory();
 179                 return NULL;
 180         }
 181
 182         for (i = 0; i < num; i++) {
 183                 PyList_SET_ITEM(ret, i, qsort_entries[i].tuple);
 184         }
 185
 186         free(qsort_entries);
 187
 188         return ret;
 189 }
 190
 191 static PyMethodDef py_objects_methods[] = {
 192         { "parse_tree", (PyCFunction)py_parse_tree, METH_VARARGS, NULL },
 193         { "sorted_tree_items", (PyCFunction)py_sorted_tree_items, METH_O, NULL },
 194         { NULL, NULL, 0, NULL }
 195 };
 196
 197 void init_objects(void)
 198 {
 199         PyObject *m;
 200
 201         m = Py_InitModule3("_objects", py_objects_methods, NULL);
 202         if (m == NULL)
 203                 return;
 204 }