Modules/grpmodule.c

   1
   2 /* UNIX group file access module */
   3
   4 #include "Python.h"
   5 #include "structseq.h"
   6
   7 #include <sys/types.h>
   8 #include <grp.h>
   9
  10 static PyStructSequence_Field struct_group_type_fields[] = {
  11    {"gr_name", "group name"},
  12    {"gr_passwd", "password"},
  13    {"gr_gid", "group id"},
  14    {"gr_mem", "group memebers"},
  15    {0}
  16 };
  17
  18 PyDoc_STRVAR(struct_group__doc__,
  19 "grp.struct_group: Results from getgr*() routines.\n\n\
  20 This object may be accessed either as a tuple of\n\
  21   (gr_name,gr_passwd,gr_gid,gr_mem)\n\
  22 or via the object attributes as named in the above tuple.\n");
  23
  24 static PyStructSequence_Desc struct_group_type_desc = {
  25    "grp.struct_group",
  26    struct_group__doc__,
  27    struct_group_type_fields,
  28    4,
  29 };
  30
  31
  32 static int initialized;
  33 static PyTypeObject StructGrpType;
  34
  35 static PyObject *
  36 mkgrent(struct group *p)
  37 {
  38     int setIndex = 0;
  39     PyObject *v = PyStructSequence_New(&StructGrpType), *w;
  40     char **member;
  41
  42     if (v == NULL)
  43         return NULL;
  44
  45     if ((w = PyList_New(0)) == NULL) {
  46         Py_DECREF(v);
  47         return NULL;
  48     }
  49     for (member = p->gr_mem; *member != NULL; member++) {
  50         PyObject *x = PyString_FromString(*member);
  51         if (x == NULL || PyList_Append(w, x) != 0) {
  52             Py_XDECREF(x);
  53             Py_DECREF(w);
  54             Py_DECREF(v);
  55             return NULL;
  56         }
  57         Py_DECREF(x);
  58     }
  59
  60 #define SET(i,val) PyStructSequence_SET_ITEM(v, i, val)
  61     SET(setIndex++, PyString_FromString(p->gr_name));
  62 #ifdef __VMS
  63     SET(setIndex++, Py_None);
  64     Py_INCREF(Py_None);
  65 #else
  66     if (p->gr_passwd)
  67             SET(setIndex++, PyString_FromString(p->gr_passwd));
  68     else {
  69             SET(setIndex++, Py_None);
  70             Py_INCREF(Py_None);
  71     }
  72 #endif
  73     SET(setIndex++, PyInt_FromLong((long) p->gr_gid));
  74     SET(setIndex++, w);
  75 #undef SET
  76
  77     if (PyErr_Occurred()) {
  78         Py_DECREF(v);
  79         return NULL;
  80     }
  81
  82     return v;
  83 }
  84
  85 static PyObject *
  86 grp_getgrgid(PyObject *self, PyObject *pyo_id)
  87 {
  88     PyObject *py_int_id;
  89     unsigned int gid;
  90     struct group *p;
  91
  92     py_int_id = PyNumber_Int(pyo_id);
  93     if (!py_int_id)
  94             return NULL;
  95     gid = PyInt_AS_LONG(py_int_id);
  96     Py_DECREF(py_int_id);
  97
  98     if ((p = getgrgid(gid)) == NULL) {
  99         PyErr_Format(PyExc_KeyError, "getgrgid(): gid not found: %d", gid);
 100         return NULL;
 101     }
 102     return mkgrent(p);
 103 }
 104
 105 static PyObject *
 106 grp_getgrnam(PyObject *self, PyObject *pyo_name)
 107 {
 108     PyObject *py_str_name;
 109     char *name;
 110     struct group *p;
 111
 112     py_str_name = PyObject_Str(pyo_name);
 113     if (!py_str_name)
 114             return NULL;
 115     name = PyString_AS_STRING(py_str_name);
 116
 117     if ((p = getgrnam(name)) == NULL) {
 118         PyErr_Format(PyExc_KeyError, "getgrnam(): name not found: %s", name);
 119         Py_DECREF(py_str_name);
 120         return NULL;
 121     }
 122
 123     Py_DECREF(py_str_name);
 124     return mkgrent(p);
 125 }
 126
 127 static PyObject *
 128 grp_getgrall(PyObject *self, PyObject *ignore)
 129 {
 130     PyObject *d;
 131     struct group *p;
 132
 133     if ((d = PyList_New(0)) == NULL)
 134         return NULL;
 135     setgrent();
 136     while ((p = getgrent()) != NULL) {
 137         PyObject *v = mkgrent(p);
 138         if (v == NULL || PyList_Append(d, v) != 0) {
 139             Py_XDECREF(v);
 140             Py_DECREF(d);
 141             endgrent();
 142             return NULL;
 143         }
 144         Py_DECREF(v);
 145     }
 146     endgrent();
 147     return d;
 148 }
 149
 150 static PyMethodDef grp_methods[] = {
 151     {"getgrgid",        grp_getgrgid,   METH_O,
 152      "getgrgid(id) -> tuple\n\
 153 Return the group database entry for the given numeric group ID.  If\n\
 154 id is not valid, raise KeyError."},
 155     {"getgrnam",        grp_getgrnam,   METH_O,
 156      "getgrnam(name) -> tuple\n\
 157 Return the group database entry for the given group name.  If\n\
 158 name is not valid, raise KeyError."},
 159     {"getgrall",        grp_getgrall,   METH_NOARGS,
 160      "getgrall() -> list of tuples\n\
 161 Return a list of all available group entries, in arbitrary order."},
 162     {NULL,              NULL}           /* sentinel */
 163 };
 164
 165 PyDoc_STRVAR(grp__doc__,
 166 "Access to the Unix group database.\n\
 167 \n\
 168 Group entries are reported as 4-tuples containing the following fields\n\
 169 from the group database, in order:\n\
 170 \n\
 171   name   - name of the group\n\
 172   passwd - group password (encrypted); often empty\n\
 173   gid    - numeric ID of the group\n\
 174   mem    - list of members\n\
 175 \n\
 176 The gid is an integer, name and password are strings.  (Note that most\n\
 177 users are not explicitly listed as members of the groups they are in\n\
 178 according to the password database.  Check both databases to get\n\
 179 complete membership information.)");
 180
 181
 182 PyMODINIT_FUNC
 183 initgrp(void)
 184 {
 185     PyObject *m, *d;
 186     m = Py_InitModule3("grp", grp_methods, grp__doc__);
 187     if (m == NULL)
 188         return;
 189     d = PyModule_GetDict(m);
 190     if (!initialized)
 191             PyStructSequence_InitType(&StructGrpType, &struct_group_type_desc);
 192     PyDict_SetItemString(d, "struct_group", (PyObject *) &StructGrpType);
 193     initialized = 1;
 194 }