Well, here's the thing, USSD does not tell us how long the decoded string will be, so at the time we call gsm_unpack() we don't know the exact length so we can only assume that it is (bin_len * 8) / 7 as per my previous patch. I attach a new patch which, after decoding, checks whether the last character in a 7-byte block is padding (0x0d) and drops it if it is (for the case when our 7-byte block only contained 7 characters). This works for Huawei modems that use PDU encoded USSD, if it is found that this works for all modems and for SMS as well, perhaps this should be moved into gsm_unpack() in src/mm-charsets.c. > Right, that's my change. Does the USSD path in the plugin know the > length of the text, or does it have to derive the text length from the > length of the hex string? If it doesn't know the length, it's going to > have the same problem I was seeing with SMS messages prior to this > change, where gsm_unpack() couldn't tell if a trailing 7-byte block > had 7 or 8 GSM7 characters in it. > > - Nathan
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