/* UNIX password file access module */

#include "Python.h"

#include "posixmodule.h"

#include <pwd.h>

#include "clinic/pwdmodule.c.h"

/*[clinic input]

module pwd

[clinic start generated code]*/

/*[clinic end generated code: output=da39a3ee5e6b4b0d input=60f628ef356b97b6]*/

static PyStructSequence_Field struct_pwd_type_fields[] = {

    {"pw_name", "user name"},

    {"pw_passwd", "password"},

    {"pw_uid", "user id"},

    {"pw_gid", "group id"},

    {"pw_gecos", "real name"},

    {"pw_dir", "home directory"},

    {"pw_shell", "shell program"},

    {0}

};

PyDoc_STRVAR(struct_passwd__doc__,

"pwd.struct_passwd: Results from getpw*() routines.\n\n\

This object may be accessed either as a tuple of\n\

  (pw_name,pw_passwd,pw_uid,pw_gid,pw_gecos,pw_dir,pw_shell)\n\

or via the object attributes as named in the above tuple.");

static PyStructSequence_Desc struct_pwd_type_desc = {

    "pwd.struct_passwd",

    struct_passwd__doc__,

    struct_pwd_type_fields,

    7,

};

PyDoc_STRVAR(pwd__doc__,

"This module provides access to the Unix password database.\n\

It is available on all Unix versions.\n\

\n\

Password database entries are reported as 7-tuples containing the following\n\

items from the password database (see `<pwd.h>'), in order:\n\

pw_name, pw_passwd, pw_uid, pw_gid, pw_gecos, pw_dir, pw_shell.\n\

The uid and gid items are integers, all others are strings. An\n\

exception is raised if the entry asked for cannot be found.");

static int initialized;

static PyTypeObject StructPwdType;

#define DEFAULT_BUFFER_SIZE 1024

static void

sets(PyObject *v, int i, const char* val)

{

  if (val) {

      PyObject *o = PyUnicode_DecodeFSDefault(val);

      PyStructSequence_SET_ITEM(v, i, o);

  }

  else {

      PyStructSequence_SET_ITEM(v, i, Py_None);

      Py_INCREF(Py_None);

  }

}

static PyObject *

mkpwent(struct passwd *p)

{

    int setIndex = 0;

    PyObject *v = PyStructSequence_New(&StructPwdType);

    if (v == NULL)

        return NULL;

#define SETI(i,val) PyStructSequence_SET_ITEM(v, i, PyLong_FromLong((long) val))

#define SETS(i,val) sets(v, i, val)

    SETS(setIndex++, p->pw_name);

#if defined(HAVE_STRUCT_PASSWD_PW_PASSWD) && !defined(__ANDROID__)

    SETS(setIndex++, p->pw_passwd);

#else

    SETS(setIndex++, "");

#endif

    PyStructSequence_SET_ITEM(v, setIndex++, _PyLong_FromUid(p->pw_uid));

    PyStructSequence_SET_ITEM(v, setIndex++, _PyLong_FromGid(p->pw_gid));

#if defined(HAVE_STRUCT_PASSWD_PW_GECOS)

    SETS(setIndex++, p->pw_gecos);

#else

    SETS(setIndex++, "");

#endif

    SETS(setIndex++, p->pw_dir);

    SETS(setIndex++, p->pw_shell);

#undef SETS

#undef SETI

    if (PyErr_Occurred()) {

        Py_XDECREF(v);

        return NULL;

    }

    return v;

}

/*[clinic input]

pwd.getpwuid

    uidobj: object

    /

Return the password database entry for the given numeric user ID.

See `help(pwd)` for more on password database entries.

[clinic start generated code]*/

static PyObject *

pwd_getpwuid(PyObject *module, PyObject *uidobj)

/*[clinic end generated code: output=c4ee1d4d429b86c4 input=ae64d507a1c6d3e8]*/

{

    PyObject *retval = NULL;

    uid_t uid;

    int nomem = 0;

    struct passwd *p;

    char *buf = NULL, *buf2 = NULL;

    if (!_Py_Uid_Converter(uidobj, &uid)) {

        if (PyErr_ExceptionMatches(PyExc_OverflowError))

            PyErr_Format(PyExc_KeyError,

                         "getpwuid(): uid not found");

        return NULL;

    }

#ifdef HAVE_GETPWUID_R

    int status;

    Py_ssize_t bufsize;

    /* Note: 'pwd' will be used via pointer 'p' on getpwuid_r success. */

    struct passwd pwd;

    Py_BEGIN_ALLOW_THREADS

    bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);

    if (bufsize == -1) {

        bufsize = DEFAULT_BUFFER_SIZE;

    }

    while(1) {

        buf2 = PyMem_RawRealloc(buf, bufsize);

        if (buf2 == NULL) {

            p = NULL;

            nomem = 1;

            break;

        }

        buf = buf2;

        status = getpwuid_r(uid, &pwd, buf, bufsize, &p);

        if (status != 0) {

            p = NULL;

        }

        if (p != NULL || status != ERANGE) {

            break;

        }

        if (bufsize > (PY_SSIZE_T_MAX >> 1)) {

            nomem = 1;

            break;

        }

        bufsize <<= 1;

    }

    Py_END_ALLOW_THREADS

#else

    p = getpwuid(uid);

#endif

    if (p == NULL) {

        PyMem_RawFree(buf);

        if (nomem == 1) {

            return PyErr_NoMemory();

        }

        PyObject *uid_obj = _PyLong_FromUid(uid);

        if (uid_obj == NULL)

            return NULL;

        PyErr_Format(PyExc_KeyError,

                     "getpwuid(): uid not found: %S", uid_obj);

        Py_DECREF(uid_obj);

        return NULL;

    }

    retval = mkpwent(p);

#ifdef HAVE_GETPWUID_R

    PyMem_RawFree(buf);

#endif

    return retval;

}

/*[clinic input]

pwd.getpwnam

    name: unicode

    /

Return the password database entry for the given user name.

See `help(pwd)` for more on password database entries.

[clinic start generated code]*/

static PyObject *

pwd_getpwnam_impl(PyObject *module, PyObject *name)

/*[clinic end generated code: output=359ce1ddeb7a824f input=a6aeb5e3447fb9e0]*/

{

    char *buf = NULL, *buf2 = NULL, *name_chars;

    int nomem = 0;

    struct passwd *p;

    PyObject *bytes, *retval = NULL;

    if ((bytes = PyUnicode_EncodeFSDefault(name)) == NULL)

        return NULL;

    /* check for embedded null bytes */

    if (PyBytes_AsStringAndSize(bytes, &name_chars, NULL) == -1)

        goto out;

#ifdef HAVE_GETPWNAM_R

    int status;

    Py_ssize_t bufsize;

    /* Note: 'pwd' will be used via pointer 'p' on getpwnam_r success. */

    struct passwd pwd;

    Py_BEGIN_ALLOW_THREADS

    bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);

    if (bufsize == -1) {

        bufsize = DEFAULT_BUFFER_SIZE;

    }

    while(1) {

        buf2 = PyMem_RawRealloc(buf, bufsize);

        if (buf2 == NULL) {

            p = NULL;

            nomem = 1;

            break;

        }

        buf = buf2;

        status = getpwnam_r(name_chars, &pwd, buf, bufsize, &p);

        if (status != 0) {

            p = NULL;

        }

        if (p != NULL || status != ERANGE) {

            break;

        }

        if (bufsize > (PY_SSIZE_T_MAX >> 1)) {

            nomem = 1;

            break;

        }

        bufsize <<= 1;

    }

    Py_END_ALLOW_THREADS

#else

    p = getpwnam(name_chars);

#endif

    if (p == NULL) {

        if (nomem == 1) {

            PyErr_NoMemory();

        }

        else {

            PyErr_Format(PyExc_KeyError,

                         "getpwnam(): name not found: %R", name);

        }

        goto out;

    }

    retval = mkpwent(p);

out:

    PyMem_RawFree(buf);

    Py_DECREF(bytes);

    return retval;

}

#ifdef HAVE_GETPWENT

/*[clinic input]

pwd.getpwall

Return a list of all available password database entries, in arbitrary order.

See help(pwd) for more on password database entries.

[clinic start generated code]*/

static PyObject *

pwd_getpwall_impl(PyObject *module)

/*[clinic end generated code: output=4853d2f5a0afac8a input=d7ecebfd90219b85]*/

{

    PyObject *d;

    struct passwd *p;

    if ((d = PyList_New(0)) == NULL)

        return NULL;

    setpwent();

    while ((p = getpwent()) != NULL) {

        PyObject *v = mkpwent(p);

        if (v == NULL || PyList_Append(d, v) != 0) {

            Py_XDECREF(v);

            Py_DECREF(d);

            endpwent();

            return NULL;

        }

        Py_DECREF(v);

    }

    endpwent();

    return d;

}

#endif

static PyMethodDef pwd_methods[] = {

    PWD_GETPWUID_METHODDEF

    PWD_GETPWNAM_METHODDEF

#ifdef HAVE_GETPWENT

    PWD_GETPWALL_METHODDEF

#endif

    {NULL,              NULL}           /* sentinel */

};

static struct PyModuleDef pwdmodule = {

    PyModuleDef_HEAD_INIT,

    "pwd",

    pwd__doc__,

    -1,

    pwd_methods,

    NULL,

    NULL,

    NULL,

    NULL

};

PyMODINIT_FUNC

PyInit_pwd(void)

{

    PyObject *m;

    m = PyModule_Create(&pwdmodule);

    if (m == NULL)

        return NULL;

    if (!initialized) {

        if (PyStructSequence_InitType2(&StructPwdType,

                                       &struct_pwd_type_desc) < 0)

            return NULL;

        initialized = 1;

    }

    Py_INCREF((PyObject *) &StructPwdType);

    PyModule_AddObject(m, "struct_passwd", (PyObject *) &StructPwdType);

    return m;

}