diff options
| -rw-r--r-- | Modules/audioop.c | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/Modules/audioop.c b/Modules/audioop.c index 014631c..d23ee2a 100644 --- a/Modules/audioop.c +++ b/Modules/audioop.c @@ -903,7 +903,7 @@ audioop_ratecv(PyObject *self, PyObject *args) int len, size, nchannels, inrate, outrate, weightA, weightB; int chan, d, *prev_i, *cur_i, cur_o; PyObject *state, *samps, *str, *rv = NULL; - int size_times_nchannels; + int bytes_per_frame; weightA = 1; weightB = 0; @@ -918,12 +918,21 @@ audioop_ratecv(PyObject *self, PyObject *args) PyErr_SetString(AudioopError, "# of channels should be >= 1"); return NULL; } + bytes_per_frame = size * nchannels; + if (bytes_per_frame / nchannels != size) { + /* This overflow test is rigorously correct because + both multiplicands are >= 1. Use the argument names + from the docs for the error msg. */ + PyErr_SetString(PyExc_OverflowError, + "width * nchannels too big for a C int"); + return NULL; + } if (weightA < 1 || weightB < 0) { PyErr_SetString(AudioopError, "weightA should be >= 1, weightB should be >= 0"); return NULL; } - if (len % (size * nchannels) != 0) { + if (len % bytes_per_frame != 0) { PyErr_SetString(AudioopError, "not a whole number of frames"); return NULL; } @@ -943,16 +952,7 @@ audioop_ratecv(PyObject *self, PyObject *args) goto exit; } - size_times_nchannels = size * nchannels; - if (size_times_nchannels / nchannels != size) { - /* This overflow test is rigorously correct because - both multiplicands are >= 1. Use the argument names - from the docs for the error msg. */ - PyErr_SetString(PyExc_OverflowError, - "width * nchannels too big for a C int"); - goto exit; - } - len /= size_times_nchannels; /* # of frames */ + len /= bytes_per_frame; /* # of frames */ if (state == Py_None) { d = -outrate; @@ -980,7 +980,7 @@ audioop_ratecv(PyObject *self, PyObject *args) { /* There are len input frames, so we need (mathematically) ceiling(len*outrate/inrate) output frames, and each frame - requires size_times_nchannels bytes. Computing this + requires bytes_per_frame bytes. Computing this without spurious overflow is the challenge. */ int ceiling; /* the number of output frames, eventually */ int nbytes; /* the number of output bytes needed */ @@ -1012,8 +1012,8 @@ audioop_ratecv(PyObject *self, PyObject *args) "not enough memory for output buffer"); goto exit; } - nbytes = ceiling * size_times_nchannels; - if (nbytes / size_times_nchannels != ceiling) { + nbytes = ceiling * bytes_per_frame; + if (nbytes / bytes_per_frame != ceiling) { PyErr_SetString(PyExc_MemoryError, "not enough memory for output buffer"); goto exit; |