diff options
Diffstat (limited to 'src/libexpr')
| -rw-r--r-- | src/libexpr/primops.cc | 697 |
1 files changed, 376 insertions, 321 deletions
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 01806a6c9493..6b9350cf87cd 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -17,6 +17,11 @@ namespace nix { +/************************************************************* + * Constants + *************************************************************/ + + static Expr primBuiltins(EvalState & state, const ATermVector & args) { /* Return an attribute set containing all primops. This allows @@ -41,6 +46,47 @@ static Expr primBuiltins(EvalState & state, const ATermVector & args) } +/* Boolean constructors. */ +static Expr primTrue(EvalState & state, const ATermVector & args) +{ + return eTrue; +} + + +static Expr primFalse(EvalState & state, const ATermVector & args) +{ + return eFalse; +} + + +/* Return the null value. */ +static Expr primNull(EvalState & state, const ATermVector & args) +{ + return makeNull(); +} + + +/* Return a string constant representing the current platform. Note! + that differs between platforms, so Nix expressions using + `__currentSystem' can evaluate to different values on different + platforms. */ +static Expr primCurrentSystem(EvalState & state, const ATermVector & args) +{ + return makeStr(thisSystem); +} + + +static Expr primCurrentTime(EvalState & state, const ATermVector & args) +{ + return ATmake("Int(<int>)", time(0)); +} + + +/************************************************************* + * Miscellaneous + *************************************************************/ + + /* Load and evaluate an expression from path specified by the argument. */ static Expr primImport(EvalState & state, const ATermVector & args) @@ -61,16 +107,201 @@ static Expr primImport(EvalState & state, const ATermVector & args) } -static Expr primPathExists(EvalState & state, const ATermVector & args) +/* Convert the argument to a string. Paths are *not* copied to the + store, so `toString /foo/bar' yields `"/foo/bar"', not + `"/nix/store/whatever..."'. */ +static Expr primToString(EvalState & state, const ATermVector & args) { PathSet context; - Path path = coerceToPath(state, args[0], context); - if (!context.empty()) - throw EvalError(format("string `%1%' cannot refer to other paths") % path); - return makeBool(pathExists(path)); + string s = coerceToString(state, args[0], context, true, false); + return makeStr(s, context); +} + + +/* Determine whether the argument is the null value. */ +static Expr primIsNull(EvalState & state, const ATermVector & args) +{ + return makeBool(matchNull(evalExpr(state, args[0]))); +} + + +static Path findDependency(Path dir, string dep) +{ + if (dep[0] == '/') throw EvalError( + format("illegal absolute dependency `%1%'") % dep); + + Path p = canonPath(dir + "/" + dep); + + if (pathExists(p)) + return p; + else + return ""; +} + + +/* Make path `p' relative to directory `pivot'. E.g., + relativise("/a/b/c", "a/b/x/y") => "../x/y". Both input paths + should be in absolute canonical form. */ +static string relativise(Path pivot, Path p) +{ + assert(pivot.size() > 0 && pivot[0] == '/'); + assert(p.size() > 0 && p[0] == '/'); + + if (pivot == p) return "."; + + /* `p' is in `pivot'? */ + Path pivot2 = pivot + "/"; + if (p.substr(0, pivot2.size()) == pivot2) { + return p.substr(pivot2.size()); + } + + /* Otherwise, `p' is in a parent of `pivot'. Find up till which + path component `p' and `pivot' match, and add an appropriate + number of `..' components. */ + string::size_type i = 1; + while (1) { + string::size_type j = pivot.find('/', i); + if (j == string::npos) break; + j++; + if (pivot.substr(0, j) != p.substr(0, j)) break; + i = j; + } + + string prefix; + unsigned int slashes = count(pivot.begin() + i, pivot.end(), '/') + 1; + while (slashes--) { + prefix += "../"; + } + + return prefix + p.substr(i); +} + + +static Expr primDependencyClosure(EvalState & state, const ATermVector & args) +{ + startNest(nest, lvlDebug, "finding dependencies"); + + Expr attrs = evalExpr(state, args[0]); + + /* Get the start set. */ + Expr startSet = queryAttr(attrs, "startSet"); + if (!startSet) throw EvalError("attribute `startSet' required"); + ATermList startSet2 = evalList(state, startSet); + + Path pivot; + PathSet workSet; + for (ATermIterator i(startSet2); i; ++i) { + PathSet context; /* !!! what to do? */ + Path p = coerceToPath(state, *i, context); + workSet.insert(p); + pivot = dirOf(p); + } + + /* Get the search path. */ + PathSet searchPath; + Expr e = queryAttr(attrs, "searchPath"); + if (e) { + ATermList list = evalList(state, e); + for (ATermIterator i(list); i; ++i) { + PathSet context; /* !!! what to do? */ + Path p = coerceToPath(state, *i, context); + searchPath.insert(p); + } + } + + Expr scanner = queryAttr(attrs, "scanner"); + if (!scanner) throw EvalError("attribute `scanner' required"); + + /* Construct the dependency closure by querying the dependency of + each path in `workSet', adding the dependencies to + `workSet'. */ + PathSet doneSet; + while (!workSet.empty()) { + Path path = *(workSet.begin()); + workSet.erase(path); + + if (doneSet.find(path) != doneSet.end()) continue; + doneSet.insert(path); + + try { + + /* Call the `scanner' function with `path' as argument. */ + debug(format("finding dependencies in `%1%'") % path); + ATermList deps = evalList(state, makeCall(scanner, makeStr(path))); + + /* Try to find the dependencies relative to the `path'. */ + for (ATermIterator i(deps); i; ++i) { + string s = evalStringNoCtx(state, *i); + + Path dep = findDependency(dirOf(path), s); + + if (dep == "") { + for (PathSet::iterator j = searchPath.begin(); + j != searchPath.end(); ++j) + { + dep = findDependency(*j, s); + if (dep != "") break; + } + } + + if (dep == "") + debug(format("did NOT find dependency `%1%'") % s); + else { + debug(format("found dependency `%1%'") % dep); + workSet.insert(dep); + } + } + + } catch (Error & e) { + e.addPrefix(format("while finding dependencies in `%1%':\n") + % path); + throw; + } + } + + /* Return a list of the dependencies we've just found. */ + ATermList deps = ATempty; + for (PathSet::iterator i = doneSet.begin(); i != doneSet.end(); ++i) { + deps = ATinsert(deps, makeStr(relativise(pivot, *i))); + deps = ATinsert(deps, makeStr(*i)); + } + + debug(format("dependency list is `%1%'") % makeList(deps)); + + return makeList(deps); } +static Expr primAbort(EvalState & state, const ATermVector & args) +{ + PathSet context; + throw Abort(format("evaluation aborted with the following error message: `%1%'") % + evalString(state, args[0], context)); +} + + +/* Return an environment variable. Use with care. */ +static Expr primGetEnv(EvalState & state, const ATermVector & args) +{ + string name = evalStringNoCtx(state, args[0]); + return makeStr(getEnv(name)); +} + + +static Expr primRelativise(EvalState & state, const ATermVector & args) +{ + PathSet context; /* !!! what to do? */ + Path pivot = coerceToPath(state, args[0], context); + Path path = coerceToPath(state, args[1], context); + return makeStr(relativise(pivot, path)); +} + + +/************************************************************* + * Derivations + *************************************************************/ + + /* Returns the hash of a derivation modulo fixed-output subderivations. A fixed-output derivation is a derivation with one output (`out') for which an expected hash and hash algorithm are @@ -324,6 +555,30 @@ static Expr primDerivationLazy(EvalState & state, const ATermVector & args) } +/************************************************************* + * Paths + *************************************************************/ + + +/* Convert the argument to a path. !!! obsolete? */ +static Expr primToPath(EvalState & state, const ATermVector & args) +{ + PathSet context; + string path = coerceToPath(state, args[0], context); + return makeStr(canonPath(path), context); +} + + +static Expr primPathExists(EvalState & state, const ATermVector & args) +{ + PathSet context; + Path path = coerceToPath(state, args[0], context); + if (!context.empty()) + throw EvalError(format("string `%1%' cannot refer to other paths") % path); + return makeBool(pathExists(path)); +} + + /* Return the base name of the given string, i.e., everything following the last slash. */ static Expr primBaseNameOf(EvalState & state, const ATermVector & args) @@ -346,24 +601,9 @@ static Expr primDirOf(EvalState & state, const ATermVector & args) } -/* Convert the argument to a string. Paths are *not* copied to the - store, so `toString /foo/bar' yields `"/foo/bar"', not - `"/nix/store/whatever..."'. */ -static Expr primToString(EvalState & state, const ATermVector & args) -{ - PathSet context; - string s = coerceToString(state, args[0], context, true, false); - return makeStr(s, context); -} - - -/* Convert the argument to a path. !!! obsolete? */ -static Expr primToPath(EvalState & state, const ATermVector & args) -{ - PathSet context; - string path = coerceToPath(state, args[0], context); - return makeStr(canonPath(path), context); -} +/************************************************************* + * Creating files + *************************************************************/ /* Convert the argument (which can be any Nix expression) to an XML @@ -406,193 +646,120 @@ static Expr primToFile(EvalState & state, const ATermVector & args) } -/* Boolean constructors. */ -static Expr primTrue(EvalState & state, const ATermVector & args) +struct FilterFromExpr : PathFilter { - return eTrue; -} + EvalState & state; + Expr filter; + + FilterFromExpr(EvalState & state, Expr filter) + : state(state), filter(filter) + { + } + bool operator () (const Path & path) + { + struct stat st; + if (lstat(path.c_str(), &st)) + throw SysError(format("getting attributes of path `%1%'") % path); -static Expr primFalse(EvalState & state, const ATermVector & args) -{ - return eFalse; -} + Expr call = + makeCall( + makeCall(filter, makeStr(path)), + makeStr( + S_ISREG(st.st_mode) ? "regular" : + S_ISDIR(st.st_mode) ? "directory" : + S_ISLNK(st.st_mode) ? "symlink" : + "unknown" /* not supported, will fail! */ + )); + + return evalBool(state, call); + } +}; -/* Return the null value. */ -static Expr primNull(EvalState & state, const ATermVector & args) +static Expr primFilterSource(EvalState & state, const ATermVector & args) { - return makeNull(); -} - + PathSet context; + Path path = coerceToPath(state, args[1], context); + if (!context.empty()) + throw EvalError(format("string `%1%' cannot refer to other paths") % path); -/* Determine whether the argument is the null value. */ -static Expr primIsNull(EvalState & state, const ATermVector & args) -{ - return makeBool(matchNull(evalExpr(state, args[0]))); -} + FilterFromExpr filter(state, args[0]); + Path dstPath = readOnlyMode + ? computeStorePathForPath(path, false, false, "", filter).first + : store->addToStore(path, false, false, "", filter); -/* Determine whether the argument is a list. */ -static Expr primIsList(EvalState & state, const ATermVector & args) -{ - ATermList list; - return makeBool(matchList(evalExpr(state, args[0]), list)); + return makeStr(dstPath, singleton<PathSet>(dstPath)); } -static Path findDependency(Path dir, string dep) -{ - if (dep[0] == '/') throw EvalError( - format("illegal absolute dependency `%1%'") % dep); - - Path p = canonPath(dir + "/" + dep); - - if (pathExists(p)) - return p; - else - return ""; -} +/************************************************************* + * Attribute sets + *************************************************************/ -/* Make path `p' relative to directory `pivot'. E.g., - relativise("/a/b/c", "a/b/x/y") => "../x/y". Both input paths - should be in absolute canonical form. */ -static string relativise(Path pivot, Path p) +/* Return the names of the attributes in an attribute set as a sorted + list of strings. */ +static Expr primAttrNames(EvalState & state, const ATermVector & args) { - assert(pivot.size() > 0 && pivot[0] == '/'); - assert(p.size() > 0 && p[0] == '/'); - - if (pivot == p) return "."; - - /* `p' is in `pivot'? */ - Path pivot2 = pivot + "/"; - if (p.substr(0, pivot2.size()) == pivot2) { - return p.substr(pivot2.size()); - } + ATermMap attrs; + queryAllAttrs(evalExpr(state, args[0]), attrs); - /* Otherwise, `p' is in a parent of `pivot'. Find up till which - path component `p' and `pivot' match, and add an appropriate - number of `..' components. */ - string::size_type i = 1; - while (1) { - string::size_type j = pivot.find('/', i); - if (j == string::npos) break; - j++; - if (pivot.substr(0, j) != p.substr(0, j)) break; - i = j; - } + StringSet names; + for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) + names.insert(aterm2String(i->key)); - string prefix; - unsigned int slashes = count(pivot.begin() + i, pivot.end(), '/') + 1; - while (slashes--) { - prefix += "../"; - } + ATermList list = ATempty; + for (StringSet::const_reverse_iterator i = names.rbegin(); + i != names.rend(); ++i) + list = ATinsert(list, makeStr(*i, PathSet())); - return prefix + p.substr(i); + return makeList(list); } -static Expr primDependencyClosure(EvalState & state, const ATermVector & args) +/* Dynamic version of the `.' operator. */ +static Expr primGetAttr(EvalState & state, const ATermVector & args) { - startNest(nest, lvlDebug, "finding dependencies"); - - Expr attrs = evalExpr(state, args[0]); + string attr = evalStringNoCtx(state, args[0]); + return evalExpr(state, makeSelect(args[1], toATerm(attr))); +} - /* Get the start set. */ - Expr startSet = queryAttr(attrs, "startSet"); - if (!startSet) throw EvalError("attribute `startSet' required"); - ATermList startSet2 = evalList(state, startSet); - Path pivot; - PathSet workSet; - for (ATermIterator i(startSet2); i; ++i) { - PathSet context; /* !!! what to do? */ - Path p = coerceToPath(state, *i, context); - workSet.insert(p); - pivot = dirOf(p); - } +/* Dynamic version of the `?' operator. */ +static Expr primHasAttr(EvalState & state, const ATermVector & args) +{ + string attr = evalStringNoCtx(state, args[0]); + return evalExpr(state, makeOpHasAttr(args[1], toATerm(attr))); +} - /* Get the search path. */ - PathSet searchPath; - Expr e = queryAttr(attrs, "searchPath"); - if (e) { - ATermList list = evalList(state, e); - for (ATermIterator i(list); i; ++i) { - PathSet context; /* !!! what to do? */ - Path p = coerceToPath(state, *i, context); - searchPath.insert(p); - } - } - Expr scanner = queryAttr(attrs, "scanner"); - if (!scanner) throw EvalError("attribute `scanner' required"); +static Expr primRemoveAttrs(EvalState & state, const ATermVector & args) +{ + ATermMap attrs; + queryAllAttrs(evalExpr(state, args[0]), attrs, true); - /* Construct the dependency closure by querying the dependency of - each path in `workSet', adding the dependencies to - `workSet'. */ - PathSet doneSet; - while (!workSet.empty()) { - Path path = *(workSet.begin()); - workSet.erase(path); - - if (doneSet.find(path) != doneSet.end()) continue; - doneSet.insert(path); - - try { - - /* Call the `scanner' function with `path' as argument. */ - debug(format("finding dependencies in `%1%'") % path); - ATermList deps = evalList(state, makeCall(scanner, makeStr(path))); - - /* Try to find the dependencies relative to the `path'. */ - for (ATermIterator i(deps); i; ++i) { - string s = evalStringNoCtx(state, *i); - - Path dep = findDependency(dirOf(path), s); + ATermList list = evalList(state, args[1]); - if (dep == "") { - for (PathSet::iterator j = searchPath.begin(); - j != searchPath.end(); ++j) - { - dep = findDependency(*j, s); - if (dep != "") break; - } - } - - if (dep == "") - debug(format("did NOT find dependency `%1%'") % s); - else { - debug(format("found dependency `%1%'") % dep); - workSet.insert(dep); - } - } + for (ATermIterator i(list); i; ++i) + /* It's not an error for *i not to exist. */ + attrs.remove(toATerm(evalStringNoCtx(state, *i))); - } catch (Error & e) { - e.addPrefix(format("while finding dependencies in `%1%':\n") - % path); - throw; - } - } + return makeAttrs(attrs); +} - /* Return a list of the dependencies we've just found. */ - ATermList deps = ATempty; - for (PathSet::iterator i = doneSet.begin(); i != doneSet.end(); ++i) { - deps = ATinsert(deps, makeStr(relativise(pivot, *i))); - deps = ATinsert(deps, makeStr(*i)); - } - debug(format("dependency list is `%1%'") % makeList(deps)); - - return makeList(deps); -} +/************************************************************* + * Lists + *************************************************************/ -static Expr primAbort(EvalState & state, const ATermVector & args) +/* Determine whether the argument is a list. */ +static Expr primIsList(EvalState & state, const ATermVector & args) { - PathSet context; - throw Abort(format("evaluation aborted with the following error message: `%1%'") % - evalString(state, args[0], context)); + ATermList list; + return makeBool(matchList(evalExpr(state, args[0]), list)); } @@ -617,34 +784,6 @@ static Expr primTail(EvalState & state, const ATermVector & args) } -/* Return an environment variable. Use with care. */ -static Expr primGetEnv(EvalState & state, const ATermVector & args) -{ - string name = evalStringNoCtx(state, args[0]); - return makeStr(getEnv(name)); -} - - -/* Return the names of the attributes in an attribute set as a sorted - list of strings. */ -static Expr primAttrNames(EvalState & state, const ATermVector & args) -{ - ATermMap attrs; - queryAllAttrs(evalExpr(state, args[0]), attrs); - - StringSet names; - for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) - names.insert(aterm2String(i->key)); - - ATermList list = ATempty; - for (StringSet::const_reverse_iterator i = names.rbegin(); - i != names.rend(); ++i) - list = ATinsert(list, makeStr(*i, PathSet())); - - return makeList(list); -} - - /* Apply a function to every element of a list. */ static Expr primMap(EvalState & state, const ATermVector & args) { @@ -659,60 +798,9 @@ static Expr primMap(EvalState & state, const ATermVector & args) } -/* Return a string constant representing the current platform. Note! - that differs between platforms, so Nix expressions using - `__currentSystem' can evaluate to different values on different - platforms. */ -static Expr primCurrentSystem(EvalState & state, const ATermVector & args) -{ - return makeStr(thisSystem); -} - - -static Expr primCurrentTime(EvalState & state, const ATermVector & args) -{ - return ATmake("Int(<int>)", time(0)); -} - - -/* Dynamic version of the `.' operator. */ -static Expr primGetAttr(EvalState & state, const ATermVector & args) -{ - string attr = evalStringNoCtx(state, args[0]); - return evalExpr(state, makeSelect(args[1], toATerm(attr))); -} - - -/* Dynamic version of the `?' operator. */ -static Expr primHasAttr(EvalState & state, const ATermVector & args) -{ - string attr = evalStringNoCtx(state, args[0]); - return evalExpr(state, makeOpHasAttr(args[1], toATerm(attr))); -} - - -static Expr primRemoveAttrs(EvalState & state, const ATermVector & args) -{ - ATermMap attrs; - queryAllAttrs(evalExpr(state, args[0]), attrs, true); - - ATermList list = evalList(state, args[1]); - - for (ATermIterator i(list); i; ++i) - /* It's not an error for *i not to exist. */ - attrs.remove(toATerm(evalStringNoCtx(state, *i))); - - return makeAttrs(attrs); -} - - -static Expr primRelativise(EvalState & state, const ATermVector & args) -{ - PathSet context; /* !!! what to do? */ - Path pivot = coerceToPath(state, args[0], context); - Path path = coerceToPath(state, args[1], context); - return makeStr(relativise(pivot, path)); -} +/************************************************************* + * Integer arithmetic + *************************************************************/ static Expr primAdd(EvalState & state, const ATermVector & args) @@ -739,54 +827,6 @@ static Expr primLessThan(EvalState & state, const ATermVector & args) } -struct FilterFromExpr : PathFilter -{ - EvalState & state; - Expr filter; - - FilterFromExpr(EvalState & state, Expr filter) - : state(state), filter(filter) - { - } - - bool operator () (const Path & path) - { - struct stat st; - if (lstat(path.c_str(), &st)) - throw SysError(format("getting attributes of path `%1%'") % path); - - Expr call = - makeCall( - makeCall(filter, makeStr(path)), - makeStr( - S_ISREG(st.st_mode) ? "regular" : - S_ISDIR(st.st_mode) ? "directory" : - S_ISLNK(st.st_mode) ? "symlink" : - "unknown" /* not supported, will fail! */ - )); - - return evalBool(state, call); - } -}; - - -static Expr primFilterSource(EvalState & state, const ATermVector & args) -{ - PathSet context; - Path path = coerceToPath(state, args[1], context); - if (!context.empty()) - throw EvalError(format("string `%1%' cannot refer to other paths") % path); - - FilterFromExpr filter(state, args[0]); - - Path dstPath = readOnlyMode - ? computeStorePathForPath(path, false, false, "", filter).first - : store->addToStore(path, false, false, "", filter); - - return makeStr(dstPath, singleton<PathSet>(dstPath)); -} - - /************************************************************* * String manipulation *************************************************************/ @@ -821,41 +861,56 @@ void EvalState::addPrimOps() { addPrimOp("builtins", 0, primBuiltins); + // Constants addPrimOp("true", 0, primTrue); addPrimOp("false", 0, primFalse); addPrimOp("null", 0, primNull); addPrimOp("__currentSystem", 0, primCurrentSystem); addPrimOp("__currentTime", 0, primCurrentTime); + // Miscellaneous addPrimOp("import", 1, primImport); - addPrimOp("__pathExists", 1, primPathExists); - addPrimOp("derivation!", 1, primDerivationStrict); - addPrimOp("derivation", 1, primDerivationLazy); - addPrimOp("baseNameOf", 1, primBaseNameOf); - addPrimOp("dirOf", 1, primDirOf); addPrimOp("toString", 1, primToString); - addPrimOp("__toPath", 1, primToPath); - addPrimOp("__toXML", 1, primToXML); addPrimOp("isNull", 1, primIsNull); - addPrimOp("__isList", 1, primIsList); addPrimOp("dependencyClosure", 1, primDependencyClosure); addPrimOp("abort", 1, primAbort); - addPrimOp("__head", 1, primHead); - addPrimOp("__tail", 1, primTail); addPrimOp("__getEnv", 1, primGetEnv); - addPrimOp("__attrNames", 1, primAttrNames); - addPrimOp("map", 2, primMap); + addPrimOp("relativise", 2, primRelativise); + + // Derivations + addPrimOp("derivation!", 1, primDerivationStrict); + addPrimOp("derivation", 1, primDerivationLazy); + + // Paths + addPrimOp("__toPath", 1, primToPath); + addPrimOp("__pathExists", 1, primPathExists); + addPrimOp("baseNameOf", 1, primBaseNameOf); + addPrimOp("dirOf", 1, primDirOf); + + // Creating files + addPrimOp("__toXML", 1, primToXML); + addPrimOp("__toFile", 2, primToFile); + addPrimOp("__filterSource", 2, primFilterSource); + + // Attribute sets + addPrimOp("__attrNames", 1, primAttrNames); addPrimOp("__getAttr", 2, primGetAttr); addPrimOp("__hasAttr", 2, primHasAttr); addPrimOp("removeAttrs", 2, primRemoveAttrs); - addPrimOp("relativise", 2, primRelativise); + + // Lists + addPrimOp("__isList", 1, primIsList); + addPrimOp("__head", 1, primHead); + addPrimOp("__tail", 1, primTail); + addPrimOp("map", 2, primMap); + + // Integer arithmetic addPrimOp("__add", 2, primAdd); addPrimOp("__sub", 2, primSub); addPrimOp("__lessThan", 2, primLessThan); - addPrimOp("__toFile", 2, primToFile); - addPrimOp("__filterSource", 2, primFilterSource); + // String manipulation addPrimOp("__substring", 3, prim_substring); addPrimOp("__stringLength", 1, prim_stringLength); } |