* Got Fix working again.

This commit is contained in:
Eelco Dolstra 2003-07-06 14:20:47 +00:00
parent f826e432aa
commit 82e3d8fafe
7 changed files with 298 additions and 23 deletions

View file

@ -1,4 +1,4 @@
bin_PROGRAMS = nix
bin_PROGRAMS = nix fix
check_PROGRAMS = test
AM_CXXFLAGS = -DSYSTEM=\"@host@\" -Wall -I..
@ -6,6 +6,9 @@ AM_CXXFLAGS = -DSYSTEM=\"@host@\" -Wall -I..
nix_SOURCES = nix.cc shared.cc
nix_LDADD = libnix.a -ldb_cxx-4 -lATerm
fix_SOURCES = fix.cc shared.cc
fix_LDADD = libnix.a -ldb_cxx-4 -lATerm
TESTS = test
test_SOURCES = test.cc

View file

@ -145,9 +145,7 @@ string printTerm(ATerm t)
}
/* Throw an exception with an error message containing the given
aterm. */
static Error badTerm(const format & f, ATerm t)
Error badTerm(const format & f, ATerm t)
{
return Error(format("%1%, in `%2%'") % f.str() % printTerm(t));
}
@ -176,7 +174,7 @@ static ATerm termFromHash(const Hash & hash)
}
static Hash writeTerm(ATerm t)
Hash writeTerm(ATerm t)
{
string path = nixStore + "/tmp.nix"; /* !!! */
if (!ATwriteToNamedTextFile(t, path.c_str()))
@ -217,18 +215,19 @@ static FState realise(RStatus & status, FState fs)
return realise(status, termFromHash(parseHash(s1)));
}
else if (ATmatch(fs, "File(<str>, <term>, [<list>])", &s1, &content, &refs)) {
else if (ATmatch(fs, "Path(<str>, <term>, [<list>])", &s1, &content, &refs)) {
string path(s1);
msg(format("realising atomic path %1%") % path);
Nest nest(true);
if (path[0] != '/') throw Error("absolute path expected: " + path);
if (path[0] != '/')
throw Error(format("path `%1% is not absolute") % path);
/* Realise referenced paths. */
ATermList refs2 = ATempty;
while (!ATisEmpty(refs)) {
refs2 = ATappend(refs2, realise(status, ATgetFirst(refs)));
refs2 = ATinsert(refs2, realise(status, ATgetFirst(refs)));
refs = ATgetNext(refs);
}
refs2 = ATreverse(refs2);
@ -238,7 +237,7 @@ static FState realise(RStatus & status, FState fs)
Hash hash = parseHash(s1);
/* Normal form. */
ATerm nf = ATmake("File(<str>, <term>, <term>)",
ATerm nf = ATmake("Path(<str>, <term>, <term>)",
path.c_str(), content, refs2);
/* Register the normal form. */
@ -261,7 +260,7 @@ static FState realise(RStatus & status, FState fs)
/* Do we know a path with that hash? If so, copy it. */
string path2 = queryFromStore(hash);
copyFile(path2, path);
copyPath(path2, path);
return nf;
}
@ -279,7 +278,7 @@ static FState realise(RStatus & status, FState fs)
/* Realise inputs. */
ATermList ins2 = ATempty;
while (!ATisEmpty(ins)) {
ins2 = ATappend(ins2, realise(status, ATgetFirst(ins)));
ins2 = ATinsert(ins2, realise(status, ATgetFirst(ins)));
ins = ATgetNext(ins);
}
ins2 = ATreverse(ins2);
@ -289,7 +288,7 @@ static FState realise(RStatus & status, FState fs)
while (!ATisEmpty(bnds)) {
ATerm bnd = ATgetFirst(bnds);
if (!ATmatch(bnd, "(<str>, <str>)", &s1, &s2))
throw badTerm("string expected", bnd);
throw badTerm("tuple of strings expected", bnd);
env[s1] = s2;
bnds = ATgetNext(bnds);
}
@ -322,7 +321,7 @@ static FState realise(RStatus & status, FState fs)
setDB(nixDB, dbRefs, outHash, outPath);
/* Register the normal form of fs. */
FState nf = ATmake("File(<str>, Hash(<str>), <term>)",
FState nf = ATmake("Path(<str>, Hash(<str>), <term>)",
outPath.c_str(), ((string) outHash).c_str(), ins2);
Hash nfHash = writeTerm(nf);
setDB(nixDB, dbSuccessors, hashTerm(fs), nfHash);

View file

@ -15,9 +15,9 @@ using namespace std;
A Nix file system state expression, or FState, describes a
(partial) state of the file system.
File : Path * Content * [FState] -> FState
Path : Path * Content * [FState] -> FState
File(path, content, refs) specifies a file object (its full path
Path(path, content, refs) specifies a file object (its full path
and contents), along with all file objects referenced by it (that
is, that it has pointers to). We assume that all files are
self-referential. This prevents us from having to deal with
@ -66,8 +66,15 @@ FState realiseFState(FState fs);
/* Return a canonical textual representation of an expression. */
string printTerm(ATerm t);
/* Throw an exception with an error message containing the given
aterm. */
Error badTerm(const format & f, ATerm t);
/* Hash an aterm. */
Hash hashTerm(ATerm t);
/* Write an aterm to the Nix store directory, and return its hash. */
Hash writeTerm(ATerm t);
#endif /* !__EVAL_H */

266
src/fix.cc Normal file
View file

@ -0,0 +1,266 @@
#include <map>
#include <iostream>
#include "globals.hh"
#include "eval.hh"
#include "values.hh"
#include "shared.hh"
typedef ATerm Expr;
static Expr evalFile(string fileName);
static bool isFState(Expr e, string & path)
{
char * s1, * s2, * s3;
Expr e1, e2;
if (ATmatch(e, "Path(<str>, <term>, [<list>])", &s1, &e1, &e2)) {
path = s1;
return true;
}
else if (ATmatch(e, "Derive(<str>, <str>, [<list>], <str>, [<list>])",
&s1, &s2, &e1, &s3, &e2))
{
path = s3;
return true;
}
else if (ATmatch(e, "Include(<str>)", &s1))
{
string fn = queryFromStore(parseHash(s1));
return isFState(evalFile(fn), path);
}
else return false;
}
static Expr substExpr(string x, Expr rep, Expr e)
{
char * s;
Expr e2;
if (ATmatch(e, "Var(<str>)", &s))
if (x == s)
return rep;
else
return e;
if (ATmatch(e, "Lam(<str>, <term>)", &s, &e2))
if (x == s)
return e;
/* !!! unfair substitutions */
/* Generically substitute in subterms. */
if (ATgetType(e) == AT_APPL) {
AFun fun = ATgetAFun(e);
int arity = ATgetArity(fun);
ATermList args = ATempty;
for (int i = arity - 1; i >= 0; i--)
args = ATinsert(args, substExpr(x, rep, ATgetArgument(e, i)));
return (ATerm) ATmakeApplList(fun, args);
}
if (ATgetType(e) == AT_LIST) {
ATermList in = (ATermList) e;
ATermList out = ATempty;
while (!ATisEmpty(in)) {
out = ATinsert(out, substExpr(x, rep, ATgetFirst(in)));
in = ATgetNext(in);
}
return (ATerm) ATreverse(out);
}
throw badTerm("do not know how to substitute", e);
}
static Expr substExprMany(ATermList formals, ATermList args, Expr body)
{
char * s;
Expr e;
/* !!! check args against formals */
while (!ATisEmpty(args)) {
ATerm tup = ATgetFirst(args);
if (!ATmatch(tup, "(<str>, <term>)", &s, &e))
throw badTerm("expected an argument tuple", tup);
body = substExpr(s, e, body);
args = ATgetNext(args);
}
return body;
}
static Expr evalExpr(Expr e)
{
char * s1;
Expr e1, e2, e3, e4;
ATermList bnds;
/* Normal forms. */
if (ATmatch(e, "<str>", &s1) ||
ATmatch(e, "Function([<list>], <term>)", &e1, &e2))
return e;
string dummy;
if (isFState(e, dummy)) return e;
/* Application. */
if (ATmatch(e, "App(<term>, [<list>])", &e1, &e2)) {
e1 = evalExpr(e1);
if (!ATmatch(e1, "Function([<list>], <term>)", &e3, &e4))
throw badTerm("expecting a function", e1);
return evalExpr(substExprMany((ATermList) e3, (ATermList) e2, e4));
}
/* Fix inclusion. */
if (ATmatch(e, "IncludeFix(<str>)", &s1)) {
string fileName(s1);
return evalFile(s1);
}
/* Relative files. */
if (ATmatch(e, "Relative(<str>)", &s1)) {
string srcPath = s1;
string dstPath;
Hash hash;
addToStore(srcPath, dstPath, hash);
return ATmake("Path(<str>, Hash(<str>), [])",
dstPath.c_str(), ((string) hash).c_str());
}
/* Packages are transformed into Derive fstate expressions. */
if (ATmatch(e, "Package([<list>])", &bnds)) {
/* Evaluate the bindings and put them in a map. */
map<string, ATerm> bndMap;
bndMap["platform"] = ATmake("<str>", SYSTEM);
while (!ATisEmpty(bnds)) {
ATerm bnd = ATgetFirst(bnds);
if (!ATmatch(bnd, "(<str>, <term>)", &s1, &e1))
throw badTerm("binding expected", bnd);
bndMap[s1] = evalExpr(e1);
bnds = ATgetNext(bnds);
}
/* Gather information for building the Derive expression. */
ATermList ins = ATempty, env = ATempty;
string builder, id;
bnds = ATempty;
for (map<string, ATerm>::iterator it = bndMap.begin();
it != bndMap.end(); it++)
{
string key = it->first;
ATerm value = it->second;
string path;
if (isFState(value, path)) {
ins = ATinsert(ins, value);
env = ATinsert(env, ATmake("(<str>, <str>)",
key.c_str(), path.c_str()));
if (key == "build") builder = path;
}
else if (ATmatch(value, "<str>", &s1)) {
if (key == "id") id = s1;
env = ATinsert(env,
ATmake("(<str>, <str>)", key.c_str(), s1));
}
else throw badTerm("invalid package argument", value);
bnds = ATinsert(bnds,
ATmake("(<str>, <term>)", key.c_str(), value));
}
/* Hash the normal form to produce a unique but deterministic
path name for this package. */
ATerm nf = ATmake("Package(<term>)", ATreverse(bnds));
debug(printTerm(nf));
Hash hash = hashTerm(nf);
if (builder == "")
throw badTerm("no builder specified", nf);
if (id == "")
throw badTerm("no package identifier specified", nf);
string out = nixStore + "/" + ((string) hash).c_str() + "-" + id;
env = ATinsert(env, ATmake("(<str>, <str>)", "out", out.c_str()));
/* Construct the result. */
e = ATmake("Derive(<str>, <str>, <term>, <str>, <term>)",
SYSTEM, builder.c_str(), ins, out.c_str(), env);
debug(printTerm(e));
/* Write the resulting term into the Nix store directory. */
Hash eHash = writeTerm(e);
return ATmake("Include(<str>)", ((string) eHash).c_str());
}
/* Barf. */
throw badTerm("invalid expression", e);
}
static Strings searchPath;
static Expr evalFile(string fileName)
{
Expr e = ATreadFromNamedFile(fileName.c_str());
if (!e) throw Error(format("cannot read aterm `%1%'") % fileName);
return evalExpr(e);
}
void run(Strings args)
{
Strings files;
searchPath.push_back(".");
for (Strings::iterator it = args.begin();
it != args.end(); )
{
string arg = *it++;
if (arg == "--includedir" || arg == "-I") {
if (it == args.end())
throw UsageError(format("argument required in `%1%'") % arg);
searchPath.push_back(*it++);
}
else if (arg[0] == '-')
throw UsageError(format("unknown flag `%1%`") % arg);
else
files.push_back(arg);
}
if (files.empty()) throw UsageError("no files specified");
for (Strings::iterator it = files.begin();
it != files.end(); it++)
{
Expr e = evalFile(*it);
char * s;
if (ATmatch(e, "Include(<str>)", &s)) {
cout << format("%1%\n") % s;
}
else throw badTerm("top level is not a package", e);
}
}
string programId = "fix";

View file

@ -120,17 +120,17 @@ void runTests()
ATmake("Foo(123)"));
string builder1fn = absPath("./test-builder-1.sh");
Hash builder1h = hashFile(builder1fn);
Hash builder1h = hashPath(builder1fn);
string fn1 = nixValues + "/builder-1.sh";
Expr e1 = ATmake("File(<str>, ExtFile(<str>, <str>), [])",
Expr e1 = ATmake("Path(<str>, ExtFile(<str>, <str>), [])",
fn1.c_str(),
builder1h.c_str(),
builder1fn.c_str());
eval(fNormalise, e1);
string fn2 = nixValues + "/refer.txt";
Expr e2 = ATmake("File(<str>, Regular(<str>), [<term>])",
Expr e2 = ATmake("Path(<str>, Regular(<str>), [<term>])",
fn2.c_str(),
("I refer to " + fn1).c_str(),
e1);
@ -144,14 +144,14 @@ void runTests()
addToStore("./test-builder-1.sh", builder1fn, builder1h);
FState fs1 = ATmake(
"File(<str>, Hash(<str>), [])",
"Path(<str>, Hash(<str>), [])",
builder1fn.c_str(),
((string) builder1h).c_str());
realise(fs1);
realise(fs1);
FState fs2 = ATmake(
"File(<str>, Hash(<str>), [])",
"Path(<str>, Hash(<str>), [])",
(builder1fn + "_bla").c_str(),
((string) builder1h).c_str());
realise(fs2);

View file

@ -34,7 +34,7 @@ struct CopySource : RestoreSource
};
void copyFile(string src, string dst)
void copyPath(string src, string dst)
{
/* Unfortunately C++ doesn't support coprocedures, so we have no
nice way to chain CopySink and CopySource together. Instead we
@ -99,7 +99,7 @@ void addToStore(string srcPath, string & dstPath, Hash & hash)
string baseName = baseNameOf(srcPath);
dstPath = nixStore + "/" + (string) hash + "-" + baseName;
copyFile(srcPath, dstPath);
copyPath(srcPath, dstPath);
setDB(nixDB, dbRefs, hash, dstPath);
}

View file

@ -8,7 +8,7 @@
using namespace std;
void copyFile(string src, string dst);
void copyPath(string src, string dst);
/* Copy a file to the nixStore directory and register it in dbRefs.
Return the hash code of the value. */