* Refactoring: get the selection path stuff out of getDerivations()

and put it into a separate function findAlongAttrPath().
This commit is contained in:
Eelco Dolstra 2006-07-26 15:05:15 +00:00
parent 2317d8f671
commit ca2238cf81
9 changed files with 170 additions and 119 deletions

View file

@ -3,7 +3,8 @@ lib_LTLIBRARIES = libexpr.la
libexpr_la_SOURCES = nixexpr.cc nixexpr.hh parser.cc parser.hh \
eval.cc eval.hh primops.cc \
lexer-tab.c lexer-tab.h parser-tab.c parser-tab.h \
get-drvs.cc get-drvs.hh
get-drvs.cc get-drvs.hh \
attr-path.cc attr-path.hh
BUILT_SOURCES = nixexpr-ast.cc nixexpr-ast.hh \
parser-tab.h lexer-tab.h parser-tab.c lexer-tab.c

74
src/libexpr/attr-path.cc Normal file
View file

@ -0,0 +1,74 @@
#include "attr-path.hh"
#include "nixexpr-ast.hh"
bool isAttrs(EvalState & state, Expr e, ATermMap & attrs)
{
e = evalExpr(state, e);
ATermList dummy;
if (!matchAttrs(e, dummy)) return false;
queryAllAttrs(e, attrs, false);
return true;
}
Expr findAlongAttrPath(EvalState & state, const string & attrPath, Expr e)
{
Strings tokens = tokenizeString(attrPath, ".");
Error attrError =
Error(format("attribute selection path `%1%' does not match expression") % attrPath);
string curPath;
for (Strings::iterator i = tokens.begin(); i != tokens.end(); ++i) {
if (!curPath.empty()) curPath += ".";
curPath += *i;
/* Is *i an index (integer) or a normal attribute name? */
enum { apAttr, apIndex } apType = apAttr;
string attr = *i;
int attrIndex = -1;
if (string2Int(attr, attrIndex)) apType = apIndex;
/* Evaluate the expression. */
e = evalExpr(state, autoCallFunction(evalExpr(state, e)));
/* It should evaluate to either an attribute set or an
expression, according to what is specified in the
attrPath. */
if (apType == apAttr) {
ATermMap attrs(128);
if (!isAttrs(state, e, attrs))
throw TypeError(
format("the expression selected by the selection path `%1%' should be an attribute set but is %2%")
% curPath % showType(e));
e = attrs.get(toATerm(attr));
if (!e)
throw Error(format("attribute `%1%' in selection path `%2%' not found") % attr % curPath);
}
else if (apType == apIndex) {
ATermList es;
if (!matchList(e, es))
throw TypeError(
format("the expression selected by the selection path `%1%' should be a list but is %2%")
% curPath % showType(e));
e = ATelementAt(es, attrIndex);
if (!e)
throw Error(format("list index %1% in selection path `%2%' not found") % attrIndex % curPath);
}
}
return e;
}

13
src/libexpr/attr-path.hh Normal file
View file

@ -0,0 +1,13 @@
#ifndef __ATTR_PATH_H
#define __ATTR_PATH_H
#include <string>
#include <map>
#include "eval.hh"
Expr findAlongAttrPath(EvalState & state, const string & attrPath, Expr e);
#endif /* !__ATTR_PATH_H */

View file

@ -287,6 +287,24 @@ static ATerm concatStrings(EvalState & state, const ATermVector & args)
}
Expr autoCallFunction(Expr e)
{
ATermList formals;
ATerm body, pos;
if (matchFunction(e, formals, body, pos)) {
for (ATermIterator i(formals); i; ++i) {
Expr name, def; ATerm values, def2;
if (!matchFormal(*i, name, values, def2)) abort();
if (!matchDefaultValue(def2, def))
throw TypeError(format("cannot auto-call a function that has an argument without a default value (`%1%')")
% aterm2String(name));
}
e = makeCall(e, makeAttrs(ATermMap(0)));
}
return e;
}
Expr evalExpr2(EvalState & state, Expr e)
{
Expr e1, e2, e3, e4;
@ -380,7 +398,9 @@ Expr evalExpr2(EvalState & state, Expr e)
}
}
else throw TypeError("the left-hand side of the function call is neither a function nor a primop (built-in operation)");
else throw TypeError(
format("the left-hand side of the function call is neither a function nor a primop (built-in operation) but %1%")
% showType(e1));
}
/* Attribute selection. */

View file

@ -59,6 +59,11 @@ string coerceToStringWithContext(EvalState & state,
ATermList & context, Expr e, bool & isPath);
Expr wrapInContext(ATermList context, Expr e);
/* Automatically call a function for which each argument has a default
value. Note: result is a call, not a normal form; it should be
evaluated by calling evalExpr(). */
Expr autoCallFunction(Expr e);
/* Print statistics. */
void printEvalStats(EvalState & state);

View file

@ -58,7 +58,7 @@ typedef set<Expr> Exprs;
it makes sense for the caller to recursively search for derivations
in `e'. */
static bool getDerivation(EvalState & state, Expr e,
DrvInfos & drvs, Exprs & doneExprs, string attributeName)
const string & attrPath, DrvInfos & drvs, Exprs & doneExprs)
{
try {
@ -92,7 +92,7 @@ static bool getDerivation(EvalState & state, Expr e,
drv.attrs = attrs;
drv.attrPath = attributeName;
drv.attrPath = attrPath;
drvs.push_back(drv);
return false;
@ -107,7 +107,7 @@ bool getDerivation(EvalState & state, Expr e, DrvInfo & drv)
{
Exprs doneExprs;
DrvInfos drvs;
getDerivation(state, e, drvs, doneExprs, "");
getDerivation(state, e, "", drvs, doneExprs);
if (drvs.size() != 1) return false;
drv = drvs.front();
return true;
@ -121,118 +121,53 @@ static string addToPath(const string & s1, const string & s2)
static void getDerivations(EvalState & state, Expr e,
DrvInfos & drvs, Exprs & doneExprs, const string & attrPath,
const string & pathTaken)
const string & pathPrefix, DrvInfos & drvs, Exprs & doneExprs)
{
/* Automatically call functions for which each argument has a
default value. */
ATermList formals;
ATerm body, pos;
if (matchFunction(e, formals, body, pos)) {
for (ATermIterator i(formals); i; ++i) {
Expr name, def; ATerm values, def2;
if (!matchFormal(*i, name, values, def2)) abort();
if (!matchDefaultValue(def2, def))
throw TypeError(format("cannot auto-call a function that has an argument without a default value (`%1%')")
% aterm2String(name));
}
getDerivations(state,
makeCall(e, makeAttrs(ATermMap(0))),
drvs, doneExprs, attrPath, pathTaken);
return;
}
/* Parse the start of attrPath. */
enum { apNone, apAttr, apIndex } apType;
string attrPathRest;
string attr;
int attrIndex;
Error attrError =
Error(format("attribute selection path `%1%' does not match expression") % attrPath);
if (attrPath.empty())
apType = apNone;
else {
string::size_type dot = attrPath.find(".");
if (dot == string::npos) {
attrPathRest = "";
attr = attrPath;
} else {
attrPathRest = string(attrPath, dot + 1);
attr = string(attrPath, 0, dot);
}
apType = apAttr;
if (string2Int(attr, attrIndex)) apType = apIndex;
}
e = evalExpr(state, autoCallFunction(evalExpr(state, e)));
/* Process the expression. */
ATermList es;
DrvInfo drv;
if (!getDerivation(state, e, drvs, doneExprs, pathTaken)) {
if (apType != apNone) throw attrError;
if (!getDerivation(state, e, pathPrefix, drvs, doneExprs))
return;
}
e = evalExpr(state, e);
if (matchAttrs(e, es)) {
if (apType != apNone && apType != apAttr) throw attrError;
ATermMap drvMap(ATgetLength(es));
queryAllAttrs(e, drvMap);
if (apType == apNone) {
for (ATermMap::const_iterator i = drvMap.begin(); i != drvMap.end(); ++i) {
startNest(nest, lvlDebug,
format("evaluating attribute `%1%'") % aterm2String(i->key));
string pathTaken2 = addToPath(pathTaken, aterm2String(i->key));
if (getDerivation(state, i->value, drvs, doneExprs, pathTaken2)) {
/* If the value of this attribute is itself an
attribute set, should we recurse into it?
=> Only if it has a `recurseForDerivations = true'
attribute. */
ATermList es;
Expr e = evalExpr(state, i->value);
if (matchAttrs(e, es)) {
ATermMap attrs(ATgetLength(es));
queryAllAttrs(e, attrs, false);
Expr e2 = attrs.get(toATerm("recurseForDerivations"));
if (e2 && evalBool(state, e2))
getDerivations(state, e, drvs, doneExprs, attrPathRest, pathTaken2);
}
for (ATermMap::const_iterator i = drvMap.begin(); i != drvMap.end(); ++i) {
startNest(nest, lvlDebug,
format("evaluating attribute `%1%'") % aterm2String(i->key));
string pathPrefix2 = addToPath(pathPrefix, aterm2String(i->key));
if (getDerivation(state, i->value, pathPrefix2, drvs, doneExprs)) {
/* If the value of this attribute is itself an
attribute set, should we recurse into it? => Only
if it has a `recurseForDerivations = true'
attribute. */
ATermList es;
Expr e = evalExpr(state, i->value);
if (matchAttrs(e, es)) {
ATermMap attrs(ATgetLength(es));
queryAllAttrs(e, attrs, false);
Expr e2 = attrs.get(toATerm("recurseForDerivations"));
if (e2 && evalBool(state, e2))
getDerivations(state, e, pathPrefix2, drvs, doneExprs);
}
}
} else {
Expr e2 = drvMap.get(toATerm(attr));
if (!e2) throw Error(format("attribute `%1%' in selection path not found") % attr);
startNest(nest, lvlDebug,
format("evaluating attribute `%1%'") % attr);
string pathTaken2 = addToPath(pathTaken, attr);
getDerivation(state, e2, drvs, doneExprs, pathTaken2);
if (!attrPath.empty())
getDerivations(state, e2, drvs, doneExprs, attrPathRest, pathTaken2);
}
return;
}
if (matchList(e, es)) {
if (apType != apNone && apType != apIndex) throw attrError;
if (apType == apNone) {
int n = 0;
for (ATermIterator i(es); i; ++i, ++n) {
startNest(nest, lvlDebug,
format("evaluating list element"));
string pathTaken2 = addToPath(pathTaken, (format("%1%") % n).str());
if (getDerivation(state, *i, drvs, doneExprs, pathTaken2))
getDerivations(state, *i, drvs, doneExprs, attrPathRest, pathTaken2);
}
} else {
Expr e2 = ATelementAt(es, attrIndex);
if (!e2) throw Error(format("list index %1% in selection path not found") % attrIndex);
int n = 0;
for (ATermIterator i(es); i; ++i, ++n) {
startNest(nest, lvlDebug,
format("evaluating list element"));
string pathTaken2 = addToPath(pathTaken, (format("%1%") % attrIndex).str());
if (getDerivation(state, e2, drvs, doneExprs, pathTaken2))
getDerivations(state, e2, drvs, doneExprs, attrPathRest, pathTaken2);
string pathPrefix2 = addToPath(pathPrefix, (format("%1%") % n).str());
if (getDerivation(state, *i, pathPrefix2, drvs, doneExprs))
getDerivations(state, *i, pathPrefix2, drvs, doneExprs);
}
return;
}
@ -241,9 +176,9 @@ static void getDerivations(EvalState & state, Expr e,
}
void getDerivations(EvalState & state, Expr e, DrvInfos & drvs,
const string & attrPath)
void getDerivations(EvalState & state, Expr e, const string & pathPrefix,
DrvInfos & drvs)
{
Exprs doneExprs;
getDerivations(state, e, drvs, doneExprs, attrPath, "");
getDerivations(state, e, pathPrefix, drvs, doneExprs);
}

View file

@ -49,8 +49,8 @@ typedef list<DrvInfo> DrvInfos;
Otherwise, return false. */
bool getDerivation(EvalState & state, Expr e, DrvInfo & drv);
void getDerivations(EvalState & state, Expr e, DrvInfos & drvs,
const string & attrPath = "");
void getDerivations(EvalState & state, Expr e, const string & pathPrefix,
DrvInfos & drvs);
#endif /* !__GET_DRVS_H */

View file

@ -10,6 +10,7 @@
#include "help.txt.hh"
#include "nixexpr-ast.hh"
#include "get-drvs.hh"
#include "attr-path.hh"
#include "pathlocks.hh"
#include <cerrno>
@ -36,7 +37,6 @@ struct InstallSourceInfo
Path nixExprPath; /* for srcNixExprDrvs, srcNixExprs */
Path profile; /* for srcProfile */
string systemFilter; /* for srcNixExprDrvs */
string attrPath; /* srcAttrPath */
};
@ -65,7 +65,7 @@ static void loadDerivations(EvalState & state, Path nixExprPath,
string systemFilter, DrvInfos & elems)
{
getDerivations(state,
parseExprFromFile(state, absPath(nixExprPath)), elems);
parseExprFromFile(state, absPath(nixExprPath)), "", elems);
/* Filter out all derivations not applicable to the current
system. */
@ -119,7 +119,7 @@ static DrvInfos queryInstalled(EvalState & state, const Path & userEnv)
e = bottomupRewrite(addPos, e);
DrvInfos elems;
getDerivations(state, e, elems);
getDerivations(state, e, "", elems);
return elems;
}
@ -334,7 +334,7 @@ static void queryInstSources(EvalState & state,
{
Expr e2 = parseExprFromString(state, *i, absPath("."));
Expr call = makeCall(e2, e1);
getDerivations(state, call, elems);
getDerivations(state, call, "", elems);
}
break;
@ -388,7 +388,9 @@ static void queryInstSources(EvalState & state,
for (Strings::const_iterator i = args.begin();
i != args.end(); ++i)
getDerivations(state,
parseExprFromFile(state, instSource.nixExprPath), elems, *i);
findAlongAttrPath(state, *i,
parseExprFromFile(state, instSource.nixExprPath)),
"", elems);
break;
}
}

View file

@ -9,6 +9,7 @@
#include "parser.hh"
#include "nixexpr-ast.hh"
#include "get-drvs.hh"
#include "attr-path.hh"
#include "help.txt.hh"
@ -18,13 +19,12 @@ void printHelp()
}
static Expr evalStdin(EvalState & state, bool parseOnly)
static Expr parseStdin(EvalState & state)
{
startNest(nest, lvlTalkative, format("evaluating standard input"));
startNest(nest, lvlTalkative, format("parsing standard input"));
string s, s2;
while (getline(cin, s2)) s += s2 + "\n";
Expr e = parseExprFromString(state, s, absPath("."));
return parseOnly ? e : evalExpr(state, e);
return parseExprFromString(state, s, absPath("."));
}
@ -34,7 +34,7 @@ static bool indirectRoot = false;
static void printResult(EvalState & state, Expr e,
bool evalOnly, bool printArgs, const string & attrPath)
bool evalOnly, bool printArgs)
{
if (evalOnly)
cout << format("%1%\n") % e;
@ -54,7 +54,7 @@ static void printResult(EvalState & state, Expr e,
else {
DrvInfos drvs;
getDerivations(state, e, drvs, attrPath);
getDerivations(state, e, "", drvs);
for (DrvInfos::iterator i = drvs.begin(); i != drvs.end(); ++i) {
Path drvPath = i->queryDrvPath(state);
if (gcRoot == "")
@ -119,18 +119,19 @@ void run(Strings args)
openDB();
if (readStdin) {
Expr e = evalStdin(state, parseOnly);
printResult(state, e, evalOnly, printArgs, attrPath);
Expr e = findAlongAttrPath(state, attrPath, parseStdin(state));
if (!parseOnly) e = evalExpr(state, e);
printResult(state, e, evalOnly, printArgs);
}
for (Strings::iterator i = files.begin();
i != files.end(); i++)
{
Path path = absPath(*i);
Expr e = parseOnly
? parseExprFromFile(state, path)
: evalFile(state, path);
printResult(state, e, evalOnly, printArgs, attrPath);
Expr e = findAlongAttrPath(state, attrPath,
parseExprFromFile(state, path));
if (!parseOnly) e = evalExpr(state, e);
printResult(state, e, evalOnly, printArgs);
}
printEvalStats(state);