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         Py_DECREF(w);
  80         return NULL;
  81     }
  82
  83     return v;
  84 }
  85
  86 static PyObject *
  87 grp_getgrgid(PyObject *self, PyObject *pyo_id)
  88 {
  89     PyObject *py_int_id;
  90     unsigned int gid;
  91     struct group *p;
  92
  93     py_int_id = PyNumber_Int(pyo_id);
  94     if (!py_int_id)
  95             return NULL;
  96     gid = PyInt_AS_LONG(py_int_id);
  97     Py_DECREF(py_int_id);
  98
  99     if ((p = getgrgid(gid)) == NULL) {
 100         PyErr_Format(PyExc_KeyError, "getgrgid(): gid not found: %d", gid);
 101         return NULL;
 102     }
 103     return mkgrent(p);
 104 }
 105
 106 static PyObject *
 107 grp_getgrnam(PyObject *self, PyObject *pyo_name)
 108 {
 109     PyObject *py_str_name;
 110     char *name;
 111     struct group *p;
 112
 113     py_str_name = PyObject_Str(pyo_name);
 114     if (!py_str_name)
 115             return NULL;
 116     name = PyString_AS_STRING(py_str_name);
 117
 118     if ((p = getgrnam(name)) == NULL) {
 119         PyErr_Format(PyExc_KeyError, "getgrnam(): name not found: %s", name);
 120         Py_DECREF(py_str_name);
 121         return NULL;
 122     }
 123
 124     Py_DECREF(py_str_name);
 125     return mkgrent(p);
 126 }
 127
 128 static PyObject *
 129 grp_getgrall(PyObject *self, PyObject *ignore)
 130 {
 131     PyObject *d;
 132     struct group *p;
 133
 134     if ((d = PyList_New(0)) == NULL)
 135         return NULL;
 136     setgrent();
 137     while ((p = getgrent()) != NULL) {
 138         PyObject *v = mkgrent(p);
 139         if (v == NULL || PyList_Append(d, v) != 0) {
 140             Py_XDECREF(v);
 141             Py_DECREF(d);
 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 }