CircuitPython - a Python implementation for teaching coding with microcontrollers https://git.suspectdevices.com/suspect-devices/circuitpython/atom?h=6.0.x 2020-09-12T19:07:23+00:00 2020-09-12T19:07:23+00:00 Jeff Epler jepler@gmail.com 2020-09-12T18:57:31+00:00 urn:sha1:54d97251fe2dd4939652a186bf703885e654b4d1 While checking whether we can enable -Wimplicit-fallthrough, I encountered a diagnostic in mp_binary_set_val_array_from_int which led to discovering the following bug: ``` >>> struct.pack("xb", 3) b'\x03\x03' ``` That is, the next value (3) was used as the value of a padding byte, while standard Python always fills "x" bytes with zeros. I initially thought this had to do with the unintentional fallthrough, but it doesn't. Instead, this code would relate to an array.array with a typecode of padding ('x'), which is ALSO not desktop Python compliant: ``` >>> array.array('x', (1, 2, 3)) array('x', [1, 0, 0]) ``` Possibly this is dead code that used to be shared between struct-setting and array-setting, but it no longer is. I also discovered that the argument list length for struct.pack and struct.pack_into were not checked, and that the length of binary data passed to array.array was not checked to be a multiple of the element size. I have corrected all of these to conform more closely to standard Python and revised some tests where necessary. Some tests for micropython-specific behavior that does not conform to standard Python and is not present in CircuitPython was deleted outright. 2017-09-01T01:11:09+00:00 Damien George damien.p.george@gmail.com 2017-09-01T01:11:09+00:00 urn:sha1:2daacc5ceef7e36ac3c88b8946088b6b3513993b Prior to this patch, the size of the buffer given to pack_into() was checked for being too small by using the count of the arguments, not their actual size. For example, a format spec of '4I' would only check that there was 4 bytes available, not 16; and 'I' would check for 1 byte, not 4. The pack() function is ok because its buffer is created to be exactly the correct size. The fix in this patch calculates the total size of the format spec at the start of pack_into() and verifies that the buffer is large enough. This adds some computational overhead, to iterate through the whole format spec. The alternative is to check during the packing, but that requires extra code to handle alignment, and the check is anyway not needed for pack(). So to maintain minimal code size the check is done using struct_calcsize. 2017-09-01T00:53:29+00:00 Damien George damien.p.george@gmail.com 2017-09-01T00:53:29+00:00 urn:sha1:79d5acbd01fed21e1c8e46b06690072375de0bfe Prior to this patch, the size of the buffer given to unpack/unpack_from was checked for being too small by using the count of the arguments, not their actual size. For example, a format spec of '4I' would only check that there was 4 bytes available, not 16; and 'I' would check for 1 byte, not 4. This bug is fixed in this patch by calculating the total size of the format spec at the start of the unpacking function. This function anyway needs to calculate the number of items at the start, so calculating the total size can be done at the same time. 2017-06-10T17:03:01+00:00 Paul Sokolovsky pfalcon@users.sourceforge.net 2017-06-10T17:03:01+00:00 urn:sha1:a2803b74f48849cb3a11fb492fee891044ecc1f4 2017-03-03T21:13:27+00:00 Paul Sokolovsky pfalcon@users.sourceforge.net 2017-03-03T21:13:27+00:00 urn:sha1:3ab6aa3a6d0506e805caa19369bef279c1c789b4 Tests which don't work with small ints are suffixed with _intbig.py. Some of these may still work with long long ints and need to be reclassified later. 2016-12-28T05:11:54+00:00 Rami Ali flowergrass@users.noreply.github.com 2016-12-28T04:29:21+00:00 urn:sha1:65574f817a949fea2316c335da866c1b8d20f1fb 2016-12-19T16:41:12+00:00 Paul Sokolovsky pfalcon@users.sourceforge.net 2016-12-19T16:40:43+00:00 urn:sha1:91359c86900ea664a8ad4fefad22b630bd714e2d 2016-10-07T01:57:25+00:00 Damien George damien.p.george@gmail.com 2016-10-07T01:57:25+00:00 urn:sha1:82af4d6749072d01195da647f54b79c80f1ad731 2016-09-19T14:01:02+00:00 Paul Sokolovsky pfalcon@users.sourceforge.net 2016-09-19T13:59:49+00:00 urn:sha1:b85bcd671c5dced62fa00f2e3c0c5541b0d16593 2016-05-14T12:54:09+00:00 Paul Sokolovsky pfalcon@users.sourceforge.net 2016-05-14T12:54:09+00:00 urn:sha1:719f8c044a9d30a8d9f4356af1310f18e82e5b67