tree a17684f8f7fd0d84e526373b7e5c475ae07bfd51
parent 8d41d722d605bc3eb2e71daea29bf21ac9031ae3
author Neels Hofmeyr <neels@hofmeyr.de> 1523584506 +0200
committer Neels Hofmeyr <neels@hofmeyr.de> 1524011917 +0200

tlv: add TLV_GET() and TLV_GET_MINLEN()

Rationale: so far we use code like

  if (TLVP_PRESENT(&tp, VERY_LONG_ENUM_VALUE_NAME_THAT_NEVER_ENDS)) {
  	val = TLVP_VAL(&tp, VERY_LONG_ENUM_VALUE_NAME_THAT_NEVER_ENDS);
	len = TLVP_LEN(&tp, VERY_L0NG_ENUM_VALUE_NAME_TH4T_NEVER_EMDS);
  }

This is a) very long and b) prone to picking the wrong name one of the three
times, which would use the wrong length or val without necessarily being
noticed. A safer and shorter, more readable pattern is:

  struct tlv_p_entry *e = TVLP_GET(&tp, VERY_LONG_ENUM_VALUE_NAME_THAT_NEVER_ENDS);
  if (!e)
        return -ENOENT;
  hexdump(e->val, e->len);

Change-Id: I445de17fc2daa3ab051f5708dd0cc185b23dc048