From 399ef8442012308f480ea5841fb6ac732207e03d Mon Sep 17 00:00:00 2001 From: Tom Bereknyei Date: Mon, 25 Sep 2023 21:30:41 -0400 Subject: [PATCH] refactor: use string accessors Create context, string_view, and c_str, accessors throughout in order to better support improvements to the underlying string representation. --- src/libcmd/repl.cc | 2 +- src/libexpr/eval-cache.cc | 8 ++++---- src/libexpr/eval.cc | 18 +++++++++--------- src/libexpr/flake/flake.cc | 10 +++++----- src/libexpr/get-drvs.cc | 12 ++++++------ src/libexpr/primops.cc | 10 +++++----- src/libexpr/primops/fetchClosure.cc | 2 +- src/libexpr/tests/primops.cc | 4 ++-- src/libexpr/value-to-json.cc | 2 +- src/libexpr/value-to-xml.cc | 6 +++--- src/libexpr/value.hh | 20 +++++++++++++++----- src/nix-env/nix-env.cc | 6 +++--- src/nix/eval.cc | 2 +- 13 files changed, 56 insertions(+), 46 deletions(-) diff --git a/src/libcmd/repl.cc b/src/libcmd/repl.cc index 944609f222a..2e17a29a71c 100644 --- a/src/libcmd/repl.cc +++ b/src/libcmd/repl.cc @@ -922,7 +922,7 @@ std::ostream & NixRepl::printValue(std::ostream & str, Value & v, unsigned int m case nString: str << ANSI_WARNING; - printLiteralString(str, v.string.s); + printLiteralString(str, v.string_view()); str << ANSI_NORMAL; break; diff --git a/src/libexpr/eval-cache.cc b/src/libexpr/eval-cache.cc index 2c9aa55327f..391b32a77dc 100644 --- a/src/libexpr/eval-cache.cc +++ b/src/libexpr/eval-cache.cc @@ -440,8 +440,8 @@ Value & AttrCursor::forceValue() if (root->db && (!cachedValue || std::get_if(&cachedValue->second))) { if (v.type() == nString) - cachedValue = {root->db->setString(getKey(), v.string.s, v.string.context), - string_t{v.string.s, {}}}; + cachedValue = {root->db->setString(getKey(), v.c_str(), v.context()), + string_t{v.c_str(), {}}}; else if (v.type() == nPath) { auto path = v.path().path; cachedValue = {root->db->setString(getKey(), path.abs()), string_t{path.abs(), {}}}; @@ -582,7 +582,7 @@ std::string AttrCursor::getString() if (v.type() != nString && v.type() != nPath) root->state.error("'%s' is not a string but %s", getAttrPathStr()).debugThrow(); - return v.type() == nString ? v.string.s : v.path().to_string(); + return v.type() == nString ? v.c_str() : v.path().to_string(); } string_t AttrCursor::getStringWithContext() @@ -624,7 +624,7 @@ string_t AttrCursor::getStringWithContext() if (v.type() == nString) { NixStringContext context; copyContext(v, context); - return {v.string.s, std::move(context)}; + return {v.c_str(), std::move(context)}; } else if (v.type() == nPath) return {v.path().to_string(), {}}; diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index afa86473092..a78c0afb19f 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -114,7 +114,7 @@ void Value::print(const SymbolTable &symbols, std::ostream &str, printLiteralBool(str, boolean); break; case tString: - printLiteralString(str, string.s); + printLiteralString(str, string_view()); break; case tPath: str << path().to_string(); // !!! escaping? @@ -339,7 +339,7 @@ static Symbol getName(const AttrName & name, EvalState & state, Env & env) Value nameValue; name.expr->eval(state, env, nameValue); state.forceStringNoCtx(nameValue, noPos, "while evaluating an attribute name"); - return state.symbols.create(nameValue.string.s); + return state.symbols.create(nameValue.string_view()); } } @@ -1343,7 +1343,7 @@ void ExprAttrs::eval(EvalState & state, Env & env, Value & v) if (nameVal.type() == nNull) continue; state.forceStringNoCtx(nameVal, i.pos, "while evaluating the name of a dynamic attribute"); - auto nameSym = state.symbols.create(nameVal.string.s); + auto nameSym = state.symbols.create(nameVal.string_view()); Bindings::iterator j = v.attrs->find(nameSym); if (j != v.attrs->end()) state.error("dynamic attribute '%1%' already defined at %2%", state.symbols[nameSym], state.positions[j->pos]).atPos(i.pos).withFrame(env, *this).debugThrow(); @@ -2155,7 +2155,7 @@ std::string_view EvalState::forceString(Value & v, const PosIdx pos, std::string forceValue(v, pos); if (v.type() != nString) error("value is %1% while a string was expected", showType(v)).debugThrow(); - return v.string.s; + return v.string_view(); } catch (Error & e) { e.addTrace(positions[pos], errorCtx); throw; @@ -2182,8 +2182,8 @@ std::string_view EvalState::forceString(Value & v, NixStringContext & context, c std::string_view EvalState::forceStringNoCtx(Value & v, const PosIdx pos, std::string_view errorCtx) { auto s = forceString(v, pos, errorCtx); - if (v.string.context) { - error("the string '%1%' is not allowed to refer to a store path (such as '%2%')", v.string.s, v.string.context[0]).withTrace(pos, errorCtx).debugThrow(); + if (v.context()) { + error("the string '%1%' is not allowed to refer to a store path (such as '%2%')", v.string_view(), v.context()[0]).withTrace(pos, errorCtx).debugThrow(); } return s; } @@ -2196,7 +2196,7 @@ bool EvalState::isDerivation(Value & v) if (i == v.attrs->end()) return false; forceValue(*i->value, i->pos); if (i->value->type() != nString) return false; - return strcmp(i->value->string.s, "derivation") == 0; + return i->value->string_view().compare("derivation") == 0; } @@ -2228,7 +2228,7 @@ BackedStringView EvalState::coerceToString( if (v.type() == nString) { copyContext(v, context); - return std::string_view(v.string.s); + return v.string_view(); } if (v.type() == nPath) { @@ -2426,7 +2426,7 @@ bool EvalState::eqValues(Value & v1, Value & v2, const PosIdx pos, std::string_v return v1.boolean == v2.boolean; case nString: - return strcmp(v1.string.s, v2.string.s) == 0; + return v1.string_view().compare(v2.string_view()) == 0; case nPath: return strcmp(v1._path, v2._path) == 0; diff --git a/src/libexpr/flake/flake.cc b/src/libexpr/flake/flake.cc index 90427e06470..a6212c12f4b 100644 --- a/src/libexpr/flake/flake.cc +++ b/src/libexpr/flake/flake.cc @@ -113,7 +113,7 @@ static FlakeInput parseFlakeInput(EvalState & state, try { if (attr.name == sUrl) { expectType(state, nString, *attr.value, attr.pos); - url = attr.value->string.s; + url = attr.value->string_view(); attrs.emplace("url", *url); } else if (attr.name == sFlake) { expectType(state, nBool, *attr.value, attr.pos); @@ -122,7 +122,7 @@ static FlakeInput parseFlakeInput(EvalState & state, input.overrides = parseFlakeInputs(state, attr.value, attr.pos, baseDir, lockRootPath); } else if (attr.name == sFollows) { expectType(state, nString, *attr.value, attr.pos); - auto follows(parseInputPath(attr.value->string.s)); + auto follows(parseInputPath(attr.value->c_str())); follows.insert(follows.begin(), lockRootPath.begin(), lockRootPath.end()); input.follows = follows; } else { @@ -131,7 +131,7 @@ static FlakeInput parseFlakeInput(EvalState & state, #pragma GCC diagnostic ignored "-Wswitch-enum" switch (attr.value->type()) { case nString: - attrs.emplace(state.symbols[attr.name], attr.value->string.s); + attrs.emplace(state.symbols[attr.name], attr.value->c_str()); break; case nBool: attrs.emplace(state.symbols[attr.name], Explicit { attr.value->boolean }); @@ -229,7 +229,7 @@ static Flake getFlake( if (auto description = vInfo.attrs->get(state.sDescription)) { expectType(state, nString, *description->value, description->pos); - flake.description = description->value->string.s; + flake.description = description->value->c_str(); } auto sInputs = state.symbols.create("inputs"); @@ -850,7 +850,7 @@ static void prim_flakeRefToString( Explicit { attr.value->boolean }); } else if (t == nString) { attrs.emplace(state.symbols[attr.name], - std::string(attr.value->str())); + std::string(attr.value->string_view())); } else { state.error( "flake reference attribute sets may only contain integers, Booleans, " diff --git a/src/libexpr/get-drvs.cc b/src/libexpr/get-drvs.cc index 506a6367763..fe3e6f7eee7 100644 --- a/src/libexpr/get-drvs.cc +++ b/src/libexpr/get-drvs.cc @@ -156,7 +156,7 @@ DrvInfo::Outputs DrvInfo::queryOutputs(bool withPaths, bool onlyOutputsToInstall Outputs result; for (auto elem : outTI->listItems()) { if (elem->type() != nString) throw errMsg; - auto out = outputs.find(elem->string.s); + auto out = outputs.find(elem->c_str()); if (out == outputs.end()) throw errMsg; result.insert(*out); } @@ -230,7 +230,7 @@ std::string DrvInfo::queryMetaString(const std::string & name) { Value * v = queryMeta(name); if (!v || v->type() != nString) return ""; - return v->string.s; + return v->c_str(); } @@ -242,7 +242,7 @@ NixInt DrvInfo::queryMetaInt(const std::string & name, NixInt def) if (v->type() == nString) { /* Backwards compatibility with before we had support for integer meta fields. */ - if (auto n = string2Int(v->string.s)) + if (auto n = string2Int(v->c_str())) return *n; } return def; @@ -256,7 +256,7 @@ NixFloat DrvInfo::queryMetaFloat(const std::string & name, NixFloat def) if (v->type() == nString) { /* Backwards compatibility with before we had support for float meta fields. */ - if (auto n = string2Float(v->string.s)) + if (auto n = string2Float(v->c_str())) return *n; } return def; @@ -271,8 +271,8 @@ bool DrvInfo::queryMetaBool(const std::string & name, bool def) if (v->type() == nString) { /* Backwards compatibility with before we had support for Boolean meta fields. */ - if (strcmp(v->string.s, "true") == 0) return true; - if (strcmp(v->string.s, "false") == 0) return false; + if (v->string_view() == "true") return true; + if (v->string_view() == "false") return false; } return def; } diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index cd9a05bb29d..1cb5cdf30f7 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -590,7 +590,7 @@ struct CompareValues case nFloat: return v1->fpoint < v2->fpoint; case nString: - return strcmp(v1->string.s, v2->string.s) < 0; + return v1->string_view().compare(v2->string_view()) < 0; case nPath: return strcmp(v1->_path, v2->_path) < 0; case nList: @@ -982,7 +982,7 @@ static void prim_trace(EvalState & state, const PosIdx pos, Value * * args, Valu { state.forceValue(*args[0], pos); if (args[0]->type() == nString) - printError("trace: %1%", args[0]->string.s); + printError("trace: %1%", args[0]->string_view()); else printError("trace: %1%", printValue(state, *args[0])); state.forceValue(*args[1], pos); @@ -1528,7 +1528,7 @@ static void prim_pathExists(EvalState & state, const PosIdx pos, Value * * args, auto path = realisePath(state, pos, arg, { .checkForPureEval = false }); /* SourcePath doesn't know about trailing slash. */ - auto mustBeDir = arg.type() == nString && arg.str().ends_with("/"); + auto mustBeDir = arg.type() == nString && arg.string_view().ends_with("/"); try { auto checked = state.checkSourcePath(path); @@ -2400,7 +2400,7 @@ static void prim_attrNames(EvalState & state, const PosIdx pos, Value * * args, (v.listElems()[n++] = state.allocValue())->mkString(state.symbols[i.name]); std::sort(v.listElems(), v.listElems() + n, - [](Value * v1, Value * v2) { return strcmp(v1->string.s, v2->string.s) < 0; }); + [](Value * v1, Value * v2) { return v1->string_view().compare(v2->string_view()) < 0; }); } static RegisterPrimOp primop_attrNames({ @@ -2541,7 +2541,7 @@ static void prim_removeAttrs(EvalState & state, const PosIdx pos, Value * * args names.reserve(args[1]->listSize()); for (auto elem : args[1]->listItems()) { state.forceStringNoCtx(*elem, pos, "while evaluating the values of the second argument passed to builtins.removeAttrs"); - names.emplace_back(state.symbols.create(elem->string.s), nullptr); + names.emplace_back(state.symbols.create(elem->string_view()), nullptr); } std::sort(names.begin(), names.end()); diff --git a/src/libexpr/primops/fetchClosure.cc b/src/libexpr/primops/fetchClosure.cc index 7fe8203f453..b86ef6b93f2 100644 --- a/src/libexpr/primops/fetchClosure.cc +++ b/src/libexpr/primops/fetchClosure.cc @@ -133,7 +133,7 @@ static void prim_fetchClosure(EvalState & state, const PosIdx pos, Value * * arg else if (attrName == "toPath") { state.forceValue(*attr.value, attr.pos); - bool isEmptyString = attr.value->type() == nString && attr.value->string.s == std::string(""); + bool isEmptyString = attr.value->type() == nString && attr.value->string_view() == ""; if (isEmptyString) { toPath = StorePathOrGap {}; } diff --git a/src/libexpr/tests/primops.cc b/src/libexpr/tests/primops.cc index ce3b5d11fae..d820b860e7c 100644 --- a/src/libexpr/tests/primops.cc +++ b/src/libexpr/tests/primops.cc @@ -711,14 +711,14 @@ namespace nix { // FIXME: add a test that verifies the string context is as expected auto v = eval("builtins.replaceStrings [\"oo\" \"a\"] [\"a\" \"i\"] \"foobar\""); ASSERT_EQ(v.type(), nString); - ASSERT_EQ(v.string.s, std::string_view("fabir")); + ASSERT_EQ(v.string_view(), "fabir"); } TEST_F(PrimOpTest, concatStringsSep) { // FIXME: add a test that verifies the string context is as expected auto v = eval("builtins.concatStringsSep \"%\" [\"foo\" \"bar\" \"baz\"]"); ASSERT_EQ(v.type(), nString); - ASSERT_EQ(std::string_view(v.string.s), "foo%bar%baz"); + ASSERT_EQ(v.string_view(), "foo%bar%baz"); } TEST_F(PrimOpTest, split1) { diff --git a/src/libexpr/value-to-json.cc b/src/libexpr/value-to-json.cc index ac3986c8700..cbc91f50979 100644 --- a/src/libexpr/value-to-json.cc +++ b/src/libexpr/value-to-json.cc @@ -31,7 +31,7 @@ json printValueAsJSON(EvalState & state, bool strict, case nString: copyContext(v, context); - out = v.string.s; + out = v.c_str(); break; case nPath: diff --git a/src/libexpr/value-to-xml.cc b/src/libexpr/value-to-xml.cc index 2539ad1c128..bd7a4ae304e 100644 --- a/src/libexpr/value-to-xml.cc +++ b/src/libexpr/value-to-xml.cc @@ -74,7 +74,7 @@ static void printValueAsXML(EvalState & state, bool strict, bool location, case nString: /* !!! show the context? */ copyContext(v, context); - doc.writeEmptyElement("string", singletonAttrs("value", v.string.s)); + doc.writeEmptyElement("string", singletonAttrs("value", v.c_str())); break; case nPath: @@ -96,14 +96,14 @@ static void printValueAsXML(EvalState & state, bool strict, bool location, if (a != v.attrs->end()) { if (strict) state.forceValue(*a->value, a->pos); if (a->value->type() == nString) - xmlAttrs["drvPath"] = drvPath = a->value->string.s; + xmlAttrs["drvPath"] = drvPath = a->value->c_str(); } a = v.attrs->find(state.sOutPath); if (a != v.attrs->end()) { if (strict) state.forceValue(*a->value, a->pos); if (a->value->type() == nString) - xmlAttrs["outPath"] = a->value->string.s; + xmlAttrs["outPath"] = a->value->c_str(); } XMLOpenElement _(doc, "derivation", xmlAttrs); diff --git a/src/libexpr/value.hh b/src/libexpr/value.hh index c44683e501e..7a1165cac4e 100644 --- a/src/libexpr/value.hh +++ b/src/libexpr/value.hh @@ -186,10 +186,9 @@ public: * For canonicity, the store paths should be in sorted order. */ struct { - const char * s; + const char * c_str; const char * * context; // must be in sorted order } string; - const char * _path; Bindings * attrs; struct { @@ -270,7 +269,7 @@ public: inline void mkString(const char * s, const char * * context = 0) { internalType = tString; - string.s = s; + string.c_str = s; string.context = context; } @@ -441,10 +440,21 @@ public: return SourcePath{CanonPath(_path)}; } - std::string_view str() const + std::string_view string_view() const + { + assert(internalType == tString); + return std::string_view(string.c_str); + } + + const char * const c_str() const { assert(internalType == tString); - return std::string_view(string.s); + return string.c_str; + } + + const char * * context() const + { + return string.context; } }; diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc index b112e8cb36a..e455a50fdd9 100644 --- a/src/nix-env/nix-env.cc +++ b/src/nix-env/nix-env.cc @@ -1228,7 +1228,7 @@ static void opQuery(Globals & globals, Strings opFlags, Strings opArgs) else { if (v->type() == nString) { attrs2["type"] = "string"; - attrs2["value"] = v->string.s; + attrs2["value"] = v->c_str(); xml.writeEmptyElement("meta", attrs2); } else if (v->type() == nInt) { attrs2["type"] = "int"; @@ -1248,7 +1248,7 @@ static void opQuery(Globals & globals, Strings opFlags, Strings opArgs) for (auto elem : v->listItems()) { if (elem->type() != nString) continue; XMLAttrs attrs3; - attrs3["value"] = elem->string.s; + attrs3["value"] = elem->c_str(); xml.writeEmptyElement("string", attrs3); } } else if (v->type() == nAttrs) { @@ -1260,7 +1260,7 @@ static void opQuery(Globals & globals, Strings opFlags, Strings opArgs) if(a.value->type() != nString) continue; XMLAttrs attrs3; attrs3["type"] = globals.state->symbols[i.name]; - attrs3["value"] = a.value->string.s; + attrs3["value"] = a.value->c_str(); xml.writeEmptyElement("string", attrs3); } } diff --git a/src/nix/eval.cc b/src/nix/eval.cc index d880bef0a7b..b34af34e0eb 100644 --- a/src/nix/eval.cc +++ b/src/nix/eval.cc @@ -85,7 +85,7 @@ struct CmdEval : MixJSON, InstallableValueCommand, MixReadOnlyOption state->forceValue(v, pos); if (v.type() == nString) // FIXME: disallow strings with contexts? - writeFile(path, v.string.s); + writeFile(path, v.string_view()); else if (v.type() == nAttrs) { if (mkdir(path.c_str(), 0777) == -1) throw SysError("creating directory '%s'", path);