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 PyTypeObject StructGrpType;
  33
  34 static PyObject *
  35 mkgrent(struct group *p)
  36 {
  37     int setIndex = 0;
  38     PyObject *v = PyStructSequence_New(&StructGrpType), *w;
  39     char **member;
  40
  41     if (v == NULL)
  42         return NULL;
  43
  44     if ((w = PyList_New(0)) == NULL) {
  45         Py_DECREF(v);
  46         return NULL;
  47     }
  48     for (member = p->gr_mem; *member != NULL; member++) {
  49         PyObject *x = PyString_FromString(*member);
  50         if (x == NULL || PyList_Append(w, x) != 0) {
  51             Py_XDECREF(x);
  52             Py_DECREF(w);
  53             Py_DECREF(v);
  54             return NULL;
  55         }
  56         Py_DECREF(x);
  57     }
  58
  59 #define SET(i,val) PyStructSequence_SET_ITEM(v, i, val)
  60     SET(setIndex++, PyString_FromString(p->gr_name));
  61 #ifdef __VMS
  62     SET(setIndex++, Py_None);
  63     Py_INCREF(Py_None);
  64 #else
  65     if (p->gr_passwd)
  66             SET(setIndex++, PyString_FromString(p->gr_passwd));
  67     else {
  68             SET(setIndex++, Py_None);
  69             Py_INCREF(Py_None);
  70     }
  71 #endif
  72     SET(setIndex++, PyInt_FromLong((long) p->gr_gid));
  73     SET(setIndex++, w);
  74 #undef SET
  75
  76     if (PyErr_Occurred()) {
  77         Py_DECREF(v);
  78         Py_DECREF(w);
  79         return NULL;
  80     }
  81
  82     return v;
  83 }
  84
  85 static PyObject *
  86 grp_getgrgid(PyObject *self, PyObject *args)
  87 {
  88     unsigned int gid;
  89     struct group *p;
  90     if (!PyArg_ParseTuple(args, "I:getgrgid", &gid))
  91         return NULL;
  92     if ((p = getgrgid(gid)) == NULL) {
  93         PyErr_Format(PyExc_KeyError, "getgrgid(): gid not found: %d", gid);
  94         return NULL;
  95     }
  96     return mkgrent(p);
  97 }
  98
  99 static PyObject *
 100 grp_getgrnam(PyObject *self, PyObject *args)
 101 {
 102     char *name;
 103     struct group *p;
 104     if (!PyArg_ParseTuple(args, "s:getgrnam", &name))
 105         return NULL;
 106     if ((p = getgrnam(name)) == NULL) {
 107         PyErr_Format(PyExc_KeyError, "getgrnam(): name not found: %s", name);
 108         return NULL;
 109     }
 110     return mkgrent(p);
 111 }
 112
 113 static PyObject *
 114 grp_getgrall(PyObject *self, PyObject *args)
 115 {
 116     PyObject *d;
 117     struct group *p;
 118
 119     if (!PyArg_ParseTuple(args, ":getgrall"))
 120         return NULL;
 121     if ((d = PyList_New(0)) == NULL)
 122         return NULL;
 123     setgrent();
 124     while ((p = getgrent()) != NULL) {
 125         PyObject *v = mkgrent(p);
 126         if (v == NULL || PyList_Append(d, v) != 0) {
 127             Py_XDECREF(v);
 128             Py_DECREF(d);
 129             return NULL;
 130         }
 131         Py_DECREF(v);
 132     }
 133     endgrent();
 134     return d;
 135 }
 136
 137 static PyMethodDef grp_methods[] = {
 138     {"getgrgid",        grp_getgrgid,   METH_VARARGS,
 139      "getgrgid(id) -> tuple\n\
 140 Return the group database entry for the given numeric group ID.  If\n\
 141 id is not valid, raise KeyError."},
 142     {"getgrnam",        grp_getgrnam,   METH_VARARGS,
 143      "getgrnam(name) -> tuple\n\
 144 Return the group database entry for the given group name.  If\n\
 145 name is not valid, raise KeyError."},
 146     {"getgrall",        grp_getgrall,   METH_VARARGS,
 147      "getgrall() -> list of tuples\n\
 148 Return a list of all available group entries, in arbitrary order."},
 149     {NULL,              NULL}           /* sentinel */
 150 };
 151
 152 PyDoc_STRVAR(grp__doc__,
 153 "Access to the Unix group database.\n\
 154 \n\
 155 Group entries are reported as 4-tuples containing the following fields\n\
 156 from the group database, in order:\n\
 157 \n\
 158   name   - name of the group\n\
 159   passwd - group password (encrypted); often empty\n\
 160   gid    - numeric ID of the group\n\
 161   mem    - list of members\n\
 162 \n\
 163 The gid is an integer, name and password are strings.  (Note that most\n\
 164 users are not explicitly listed as members of the groups they are in\n\
 165 according to the password database.  Check both databases to get\n\
 166 complete membership information.)");
 167
 168
 169 PyMODINIT_FUNC
 170 initgrp(void)
 171 {
 172     PyObject *m, *d;
 173     m = Py_InitModule3("grp", grp_methods, grp__doc__);
 174     if (m == NULL)
 175         return;
 176     d = PyModule_GetDict(m);
 177     PyStructSequence_InitType(&StructGrpType, &struct_group_type_desc);
 178     PyDict_SetItemString(d, "struct_group", (PyObject *) &StructGrpType);
 179 }