nixos/nix
1
1
Fork 0
mirror of https://github.com/NixOS/nix.git synced 2025-11-15 15:02:42 +01:00
Code Activity

Add error reporting to machine spec paser

Browse source 
Currently machine specification (`/etc/nix/machine`) parser fails
with a vague exception if the file had incorrect format.
This commit adds verbose exceptions and unit-tests for the parser.
This commit is contained in:
Alexey Novikov 2021-10-12 16:18:44 +04:00
parent 64a3b045c1
commit e989c83b44
5 changed files with 227 additions and 25 deletions
Download patch file Download diff file Expand all files Collapse all files

78
src/libstore/machines.cc
View file

@ -83,53 +83,83 @@ ref<Store> Machine::openStore() const {
return nix::openStore(storeUri, storeParams);
}
void parseMachines(const std::string & s, Machines & machines)
{
for (auto line : tokenizeString<std::vector<string>>(s, "\n;")) {
static std::vector<std::string> expandBuilderLines(const std::string& builders) {
std::vector<std::string> result;
for (auto line : tokenizeString<std::vector<string>>(builders, "\n;")) {
trim(line);
line.erase(std::find(line.begin(), line.end(), '#'), line.end());
if (line.empty()) continue;
if (line[0] == '@') {
auto file = trim(std::string(line, 1));
const std::string path = trim(std::string(line, 1));
std::string text;
try {
parseMachines(readFile(file), machines);
text = readFile(path);
} catch (const SysError & e) {
if (e.errNo != ENOENT)
throw;
debug("cannot find machines file '%s'", file);
debug("cannot find machines file '%s'", path);
}
const auto lines = expandBuilderLines(text);
result.insert(end(result), begin(lines), end(lines));
continue;
}
auto tokens = tokenizeString<std::vector<string>>(line);
auto sz = tokens.size();
if (sz < 1)
throw FormatError("bad machine specification '%s'", line);
result.emplace_back(line);
}
return result;
}
auto isSet = [&](size_t n) {
return tokens.size() > n && tokens[n] != "" && tokens[n] != "-";
};
static Machine parseBuilderLine(const std::string& line) {
const auto tokens = tokenizeString<std::vector<string>>(line);
machines.emplace_back(tokens[0],
auto isSet = [&](size_t fieldIndex) {
return tokens.size() > fieldIndex && tokens[fieldIndex] != "" && tokens[fieldIndex] != "-";
};
auto parseUnsignedIntField = [&](size_t fieldIndex) {
const auto result = string2Int<unsigned int>(tokens[fieldIndex]);
if (!result) {
throw FormatError("bad machine specification: failed to convert column #%lu in a row: '%s' to 'unsigned int'", fieldIndex, line);
}
return result.value();
};
auto ensureBase64 = [&](size_t fieldIndex) {
const auto& str = tokens[fieldIndex];
try {
base64Decode(str);
} catch (const Error& e) {
throw FormatError("bad machine specification: a column #%lu in a row: '%s' is not valid base64 string: %s", fieldIndex, line, e.what());
}
return str;
};
if (!isSet(0)) {
throw FormatError("bad machine specification: store URI was not found at the first column of a row: '%s'", line);
}
return {tokens[0],
isSet(1) ? tokenizeString<std::vector<string>>(tokens[1], ",") : std::vector<string>{settings.thisSystem},
isSet(2) ? tokens[2] : "",
isSet(3) ? std::stoull(tokens[3]) : 1LL,
isSet(4) ? std::stoull(tokens[4]) : 1LL,
isSet(3) ? parseUnsignedIntField(3) : 1U,
isSet(4) ? parseUnsignedIntField(4) : 1U,
isSet(5) ? tokenizeString<std::set<string>>(tokens[5], ",") : std::set<string>{},
isSet(6) ? tokenizeString<std::set<string>>(tokens[6], ",") : std::set<string>{},
isSet(7) ? tokens[7] : "");
}
isSet(7) ? ensureBase64(7) : ""};
}
static Machines parseBuilderLines(const std::vector<std::string>& builders) {
Machines result;
std::transform(builders.begin(), builders.end(), std::back_inserter(result), parseBuilderLine);
return result;
}
Machines getMachines()
{
static auto machines = [&]() {
Machines machines;
parseMachines(settings.builders, machines);
return machines;
}();
return machines;
const auto builderLines = expandBuilderLines(settings.builders);
return parseBuilderLines(builderLines);
}
}