Patch #102469: Use glibc's getline() extension when reading unbounded lines

diff --git a/Objects/fileobject.c b/Objects/fileobject.c
index 61023dcc8614251e9cf03331f8b323a3c96290ac..d008ff7a0206ec4474ffec6998f266b4cb452476 100644 (file)
--- a/Objects/fileobject.c
+++ b/Objects/fileobject.c
@@ -645,13 +645,40 @@ file_readinto(PyFileObject *f, PyObject *args)
 static PyObject *
 get_line(PyFileObject *f, int n)
 {
-       register FILE *fp;
+       register FILE *fp = f->f_fp;
        register int c;
-       register char *buf, *end;
+       char *buf, *end;
        size_t n1, n2;
        PyObject *v;
 
-       fp = f->f_fp;
+#ifdef HAVE_GETLINE
+       /* Use GNU libc extension getline() for arbitrary-sized lines */
+       if (n == 0) {
+               size_t size = 0;
+               buf = NULL;
+               Py_BEGIN_ALLOW_THREADS
+               n1 = getline(&buf, &size, fp);
+               Py_END_ALLOW_THREADS
+               if (n1 == -1) {
+                       clearerr(fp);
+                       if (PyErr_CheckSignals()) {
+                               return NULL;
+                       }
+                       if (n < 0 && feof(fp)) {
+                               PyErr_SetString(PyExc_EOFError,
+                                               "EOF when reading a line");
+                               return NULL;
+                       }
+                       return PyString_FromStringAndSize(NULL, 0);
+               }
+               /* No error */
+               
+               v = PyString_FromStringAndSize(buf, n1);
+               free(buf);
+               return v;
+       }
+#endif
+
        n2 = n > 0 ? n : 100;
        v = PyString_FromStringAndSize((char *)NULL, n2);
        if (v == NULL)