diff options
Diffstat (limited to 'lib/dvb/db.cpp')
| -rw-r--r-- | lib/dvb/db.cpp | 183 |
1 files changed, 181 insertions, 2 deletions
diff --git a/lib/dvb/db.cpp b/lib/dvb/db.cpp index fe4bcc76..4e0332ba 100644 --- a/lib/dvb/db.cpp +++ b/lib/dvb/db.cpp @@ -357,13 +357,192 @@ RESULT eDVBDBQuery::getNextResult(eServiceReferenceDVB &ref) return 1; } -RESULT eDVBChannelQuery::compile(ePtr<eDVBChannelQuery> &res, std::string query) +/* (<name|provider|type|bouquet|satpos|chid> <==|...> <"string"|int>)[AND (..)] */ + + /* never, NEVER write a parser in C++! */ +RESULT parseExpression(ePtr<eDVBChannelQuery> &res, std::list<std::string>::const_iterator begin, std::list<std::string>::const_iterator end) { + std::list<std::string>::const_iterator end_of_exp; + if (*begin == "(") + { + end_of_exp = begin; + while (end_of_exp != end) + if (*end_of_exp == ")") + break; + else + ++end_of_exp; + + if (end_of_exp == end) + { + eDebug("expression parse: end of expression while searching for closing brace"); + return -1; + } + + ++begin; + // begin..end_of_exp + int r = parseExpression(res, begin, end_of_exp); + if (r) + return r; + ++end_of_exp; + + /* we had only one sub expression */ + if (end_of_exp == end) + return 1; + + /* otherwise we have an operator here.. */ + + ePtr<eDVBChannelQuery> r2 = res; + res = new eDVBChannelQuery(); + res->m_p1 = r2; + res->m_inverse = 0; + r2 = 0; + + if (*end_of_exp == "||") + res->m_type = eDVBChannelQuery::tOR; + else if (*end_of_exp == "&&") + res->m_type = eDVBChannelQuery::tAND; + else + { + eDebug("found operator %s, but only && and || are allowed!", end_of_exp->c_str()); + res = 0; + return 1; + } + + ++end_of_exp; + + return parseExpression(res->m_p2, end_of_exp, end); + } + + // "begin" <op> "end" + std::string type, op, val; + + res = new eDVBChannelQuery(); + + int cnt = 0; + while (begin != end) + { + switch (cnt) + { + case 0: + type = *begin; + break; + case 1: + op = *begin; + break; + case 2: + val = *begin; + break; + case 3: + eDebug("malformed query: got '%s', but expected only <type> <op> <val>", begin->c_str()); + return 1; + } + ++begin; + ++cnt; + } + + if (cnt != 3) + { + eDebug("malformed query: missing stuff"); + res = 0; + return 1; + } + + if (type == "name") + res->m_type = eDVBChannelQuery::tName; + else if (type == "provider") + res->m_type = eDVBChannelQuery::tProvider; + else if (type == "type") + res->m_type = eDVBChannelQuery::tType; + else if (type == "bouquet") + res->m_type = eDVBChannelQuery::tBouquet; + else if (type == "satellitePosition") + res->m_type = eDVBChannelQuery::tSatellitePosition; + else if (type == "channelID") + res->m_type = eDVBChannelQuery::tChannelID; + else + { + eDebug("malformed query: invalid type %s", type.c_str()); + res = 0; + return 1; + } + + eDebug("type is %d, nice!", res->m_type); + + if (op == "==") + res->m_inverse = 0; + else if (op == "!=") + res->m_inverse = 1; + else + { + eDebug("invalid operator %s", op.c_str()); + res = 0; + return 1; + } + + res->m_string = val; + res->m_int = atoi(val.c_str()); +// res->m_channelid = eDVBChannelID(val); + + return 0; +} + +RESULT eDVBChannelQuery::compile(ePtr<eDVBChannelQuery> &res, const eServiceReferenceDVB &source, std::string query) +{ + std::list<std::string> tokens; + + m_source = source; + + std::string current_token; + +// eDebug("splitting %s....", query.c_str()); + unsigned int i = 0; + const char *splitchars="()"; + int quotemode = 0, lastsplit = 0, lastalnum = 0; + while (i <= query.size()) + { + int c = (i < query.size()) ? query[i] : ' '; + ++i; + + int issplit = !!strchr(splitchars, c); + int isaln = isalnum(c); + int iswhite = c == ' '; + int isquot = c == '\"'; + + if (quotemode) + { + iswhite = issplit = 0; + isaln = lastalnum; + } + + if (issplit || iswhite || isquot || lastsplit || (lastalnum != isaln)) + { + if (current_token.size()) + tokens.push_back(current_token); + current_token.clear(); + } + + if (!(iswhite || isquot)) + current_token += c; + + if (isquot) + quotemode = !quotemode; + lastsplit = issplit; + lastalnum = isaln; + } + +// for (std::list<std::string>::const_iterator a(tokens.begin()); a != tokens.end(); ++a) +// { +// printf("%s\n", a->c_str()); +// } + + /* now we recursivly parse that. */ + return parseExpression(res, tokens.begin(), tokens.end()); +/* res = new eDVBChannelQuery(); res->m_type = eDVBChannelQuery::tName; res->m_inverse = 0; res->m_string = query; - return 0; + return 0; */ } DEFINE_REF(eDVBChannelQuery); |