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/* 
posixshmem - A Python extension that provides shm_open() and shm_unlink() 
*/ 
 
#define PY_SSIZE_T_CLEAN 
 
#include <Python.h> 
 
// for shm_open() and shm_unlink() 
#ifdef HAVE_SYS_MMAN_H 
#include <sys/mman.h> 
#endif 
 
/*[clinic input] 
module _posixshmem 
[clinic start generated code]*/ 
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=a416734e49164bf8]*/ 
 
/* 
 * 
 * Module-level functions & meta stuff 
 * 
 */ 
 
#ifdef HAVE_SHM_OPEN 
/*[clinic input] 
_posixshmem.shm_open -> int 
    path: unicode 
    flags: int 
    mode: int = 0o777 
 
# "shm_open(path, flags, mode=0o777)\n\n\ 
 
Open a shared memory object.  Returns a file descriptor (integer). 
 
[clinic start generated code]*/ 
 
static int 
_posixshmem_shm_open_impl(PyObject *module, PyObject *path, int flags, 
                          int mode) 
/*[clinic end generated code: output=8d110171a4fa20df input=e83b58fa802fac25]*/ 
{ 
    int fd; 
    int async_err = 0; 
    const char *name = PyUnicode_AsUTF8(path); 
    if (name == NULL) { 
        return -1; 
    } 
    do { 
        Py_BEGIN_ALLOW_THREADS 
        fd = shm_open(name, flags, mode); 
        Py_END_ALLOW_THREADS 
    } while (fd < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals())); 
 
    if (fd < 0) { 
        if (!async_err) 
            PyErr_SetFromErrnoWithFilenameObject(PyExc_OSError, path); 
        return -1; 
    } 
 
    return fd; 
} 
#endif /* HAVE_SHM_OPEN */ 
 
#ifdef HAVE_SHM_UNLINK 
/*[clinic input] 
_posixshmem.shm_unlink 
    path: unicode 
 
Remove a shared memory object (similar to unlink()). 
 
Remove a shared memory object name, and, once all processes  have  unmapped 
the object, de-allocates and destroys the contents of the associated memory 
region. 
 
[clinic start generated code]*/ 
 
static PyObject * 
_posixshmem_shm_unlink_impl(PyObject *module, PyObject *path) 
/*[clinic end generated code: output=42f8b23d134b9ff5 input=8dc0f87143e3b300]*/ 
{ 
    int rv; 
    int async_err = 0; 
    const char *name = PyUnicode_AsUTF8(path); 
    if (name == NULL) { 
        return NULL; 
    } 
    do { 
        Py_BEGIN_ALLOW_THREADS 
        rv = shm_unlink(name); 
        Py_END_ALLOW_THREADS 
    } while (rv < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals())); 
 
    if (rv < 0) { 
        if (!async_err) 
            PyErr_SetFromErrnoWithFilenameObject(PyExc_OSError, path); 
        return NULL; 
    } 
 
    Py_RETURN_NONE; 
} 
#endif /* HAVE_SHM_UNLINK */ 
 
#include "clinic/posixshmem.c.h" 
 
static PyMethodDef module_methods[ ] = { 
    _POSIXSHMEM_SHM_OPEN_METHODDEF 
    _POSIXSHMEM_SHM_UNLINK_METHODDEF 
    {NULL} /* Sentinel */ 
}; 
 
 
static struct PyModuleDef this_module = { 
    PyModuleDef_HEAD_INIT,  // m_base 
    "_posixshmem",          // m_name 
    "POSIX shared memory module",     // m_doc 
    -1,                     // m_size (space allocated for module globals) 
    module_methods,         // m_methods 
}; 
 
/* Module init function */ 
PyMODINIT_FUNC 
PyInit__posixshmem(void) { 
    PyObject *module; 
    module = PyModule_Create(&this_module); 
    if (!module) { 
        return NULL; 
    } 
    return module; 
}