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