gh-96670: Raise SyntaxError when parsing NULL bytes (#97594)

1 files changed, 19 insertions, 10 deletions

diff --git a/Objects/fileobject.c b/Objects/fileobject.c
index cbc5741..ab67cd2 100644
--- a/Objects/fileobject.c
+++ b/Objects/fileobject.c
@@ -230,16 +230,8 @@ _PyLong_FileDescriptor_Converter(PyObject *o, void *ptr)
     return 1;
 }
 
-/*
-** Py_UniversalNewlineFgets is an fgets variation that understands
-** all of \r, \n and \r\n conventions.
-** The stream should be opened in binary mode.
-** The fobj parameter exists solely for legacy reasons and must be NULL.
-** Note that we need no error handling: fgets() treats error and eof
-** identically.
-*/
 char *
-Py_UniversalNewlineFgets(char *buf, int n, FILE *stream, PyObject *fobj)
+_Py_UniversalNewlineFgetsWithSize(char *buf, int n, FILE *stream, PyObject *fobj, size_t* size)
 {
     char *p = buf;
     int c;
@@ -265,11 +257,28 @@ Py_UniversalNewlineFgets(char *buf, int n, FILE *stream, PyObject *fobj)
     }
     FUNLOCKFILE(stream);
     *p = '\0';
-    if (p == buf)
+    if (p == buf) {
         return NULL;
+    }
+    *size = p - buf;
     return buf;
 }
 
+/*
+** Py_UniversalNewlineFgets is an fgets variation that understands
+** all of \r, \n and \r\n conventions.
+** The stream should be opened in binary mode.
+** The fobj parameter exists solely for legacy reasons and must be NULL.
+** Note that we need no error handling: fgets() treats error and eof
+** identically.
+*/
+
+char *
+Py_UniversalNewlineFgets(char *buf, int n, FILE *stream, PyObject *fobj) {
+    size_t size;
+    return _Py_UniversalNewlineFgetsWithSize(buf, n, stream, fobj, &size);
+}
+
 /* **************************** std printer ****************************
  * The stdprinter is used during the boot strapping phase as a preliminary
  * file like object for sys.stderr.