audioop_ratecv(): I left a potentially unsafe multiply unchecked
yesterday -- repair that. Also renamed the silly size_times_nchannels
to bytes_per_frame.
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 @@
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 @@
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 @@
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 @@
{
/* 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 @@
"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;