nix-super/src/nix/search.cc
pennae 8775be3393 store Symbols in a table as well, like positions
this slightly increases the amount of memory used for any given symbol, but this
increase is more than made up for if the symbol is referenced more than once in
the EvalState that holds it. on average every symbol should be referenced at
least twice (once to introduce a binding, once to use it), so we expect no
increase in memory on average.

symbol tables are limited to 2³² entries like position tables, and similar
arguments apply to why overflow is not likely: 2³² symbols would require as many
string instances (at 24 bytes each) and map entries (at 24 bytes or more each,
assuming that the map holds on average at most one item per bucket as the docs
say). a full symbol table would require at least 192GB of memory just for
symbols, which is well out of reach. (an ofborg eval of nixpks today creates
less than a million symbols!)
2022-04-21 21:56:31 +02:00

177 lines
6.3 KiB
C++

#include "command.hh"
#include "globals.hh"
#include "eval.hh"
#include "eval-inline.hh"
#include "names.hh"
#include "get-drvs.hh"
#include "common-args.hh"
#include "json.hh"
#include "shared.hh"
#include "eval-cache.hh"
#include "attr-path.hh"
#include "hilite.hh"
#include <regex>
#include <fstream>
using namespace nix;
std::string wrap(std::string prefix, std::string s)
{
return prefix + s + ANSI_NORMAL;
}
struct CmdSearch : InstallableCommand, MixJSON
{
std::vector<std::string> res;
CmdSearch()
{
expectArgs("regex", &res);
}
std::string description() override
{
return "search for packages";
}
std::string doc() override
{
return
#include "search.md"
;
}
Strings getDefaultFlakeAttrPaths() override
{
return {
"packages." + settings.thisSystem.get() + ".",
"legacyPackages." + settings.thisSystem.get() + "."
};
}
void run(ref<Store> store) override
{
settings.readOnlyMode = true;
evalSettings.enableImportFromDerivation.setDefault(false);
// Empty search string should match all packages
// Use "^" here instead of ".*" due to differences in resulting highlighting
// (see #1893 -- libc++ claims empty search string is not in POSIX grammar)
if (res.empty())
res.push_back("^");
std::vector<std::regex> regexes;
regexes.reserve(res.size());
for (auto & re : res)
regexes.push_back(std::regex(re, std::regex::extended | std::regex::icase));
auto state = getEvalState();
auto jsonOut = json ? std::make_unique<JSONObject>(std::cout) : nullptr;
uint64_t results = 0;
std::function<void(eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath, bool initialRecurse)> visit;
visit = [&](eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath, bool initialRecurse)
{
Activity act(*logger, lvlInfo, actUnknown,
fmt("evaluating '%s'", concatStringsSep(".", attrPath)));
try {
auto recurse = [&]()
{
for (const auto & attr : cursor.getAttrs()) {
auto cursor2 = cursor.getAttr(attr);
auto attrPath2(attrPath);
attrPath2.push_back(attr);
visit(*cursor2, attrPath2, false);
}
};
if (cursor.isDerivation()) {
DrvName name(cursor.getAttr("name")->getString());
auto aMeta = cursor.maybeGetAttr("meta");
auto aDescription = aMeta ? aMeta->maybeGetAttr("description") : nullptr;
auto description = aDescription ? aDescription->getString() : "";
std::replace(description.begin(), description.end(), '\n', ' ');
auto attrPath2 = concatStringsSep(".", attrPath);
std::vector<std::smatch> attrPathMatches;
std::vector<std::smatch> descriptionMatches;
std::vector<std::smatch> nameMatches;
bool found = false;
for (auto & regex : regexes) {
found = false;
auto addAll = [&found](std::sregex_iterator it, std::vector<std::smatch> & vec) {
const auto end = std::sregex_iterator();
while (it != end) {
vec.push_back(*it++);
found = true;
}
};
addAll(std::sregex_iterator(attrPath2.begin(), attrPath2.end(), regex), attrPathMatches);
addAll(std::sregex_iterator(name.name.begin(), name.name.end(), regex), nameMatches);
addAll(std::sregex_iterator(description.begin(), description.end(), regex), descriptionMatches);
if (!found)
break;
}
if (found)
{
results++;
if (json) {
auto jsonElem = jsonOut->object(attrPath2);
jsonElem.attr("pname", name.name);
jsonElem.attr("version", name.version);
jsonElem.attr("description", description);
} else {
auto name2 = hiliteMatches(name.name, std::move(nameMatches), ANSI_GREEN, "\e[0;2m");
if (results > 1) logger->cout("");
logger->cout(
"* %s%s",
wrap("\e[0;1m", hiliteMatches(attrPath2, std::move(attrPathMatches), ANSI_GREEN, "\e[0;1m")),
name.version != "" ? " (" + name.version + ")" : "");
if (description != "")
logger->cout(
" %s", hiliteMatches(description, std::move(descriptionMatches), ANSI_GREEN, ANSI_NORMAL));
}
}
}
else if (
attrPath.size() == 0
|| (attrPath[0] == "legacyPackages" && attrPath.size() <= 2)
|| (attrPath[0] == "packages" && attrPath.size() <= 2))
recurse();
else if (initialRecurse)
recurse();
else if (attrPath[0] == "legacyPackages" && attrPath.size() > 2) {
auto attr = cursor.maybeGetAttr("recurseForDerivations");
if (attr && attr->getBool())
recurse();
}
} catch (EvalError & e) {
if (!(attrPath.size() > 0 && attrPath[0] == "legacyPackages"))
throw;
}
};
for (auto & cursor : installable->getCursors(*state))
visit(*cursor, cursor->getAttrPath(), true);
if (!json && !results)
throw Error("no results for the given search term(s)!");
}
};
static auto rCmdSearch = registerCommand<CmdSearch>("search");