Update of /cvsroot/python/python/dist/src/Objects In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv22227/Objects Modified Files: fileobject.c Log Message: Disallow opening files with modes 'aU' or 'wU' as specified by PEP 278. Closes bug 967182. Index: fileobject.c =================================================================== RCS file: /cvsroot/python/python/dist/src/Objects/fileobject.c,v retrieving revision 2.193 retrieving revision 2.194 diff -u -d -r2.193 -r2.194 --- fileobject.c 7 Nov 2004 14:15:28 -0000 2.193 +++ fileobject.c 20 May 2005 03:07:05 -0000 2.194 @@ -128,6 +128,54 @@ return (PyObject *) f; } +/* check for known incorrect mode strings - problem is, platforms are + free to accept any mode characters they like and are supposed to + ignore stuff they don't understand... write or append mode with + universal newline support is expressly forbidden by PEP 278. */ +/* zero return is kewl - one is un-kewl */ +static int +check_the_mode(char *mode) +{ + unsigned int len = strlen(mode); + + switch (len) { + case 0: + PyErr_SetString(PyExc_ValueError, "empty mode string"); + return 1; + + /* reject wU, aU */ + case 2: + switch (mode[0]) { + case 'w': + case 'a': + if (mode[1] == 'U') { + PyErr_SetString(PyExc_ValueError, + "invalid mode string"); + return 1; + } + break; + } + break; + + /* reject w+U, a+U, wU+, aU+ */ + case 3: + switch (mode[0]) { + case 'w': + case 'a': + if ((mode[1] == '+' && mode[2] == 'U') || + (mode[1] == 'U' && mode[2] == '+')) { + PyErr_SetString(PyExc_ValueError, + "invalid mode string"); + return 1; + } + break; + } + break; + } + + return 0; +} + static PyObject * open_the_file(PyFileObject *f, char *name, char *mode) { @@ -142,6 +190,9 @@ assert(mode != NULL); assert(f->f_fp == NULL); + if (check_the_mode(mode)) + return NULL; + /* rexec.py can't stop a user from getting the file() constructor -- all they have to do is get *any* file object f, and then do type(f). Here we prevent them from doing damage with it. */