forked from lix-project/lix
* Realisation of File(...) expressions.
This commit is contained in:
Eelco Dolstra
parent
bb03c45ca0
commit
3da9687854
278
src/eval.cc
278
src/eval.cc
|
|
@ -30,6 +30,7 @@ bool pathExists(string path)
|
|||
}
|
||||
|
||||
|
||||
#if 0
|
||||
/* Compute a derived value by running a program. */
|
||||
static Hash computeDerived(Hash sourceHash, string targetName,
|
||||
string platform, Hash prog, Environment env)
|
||||
|
|
@ -175,6 +176,7 @@ static Hash computeDerived(Hash sourceHash, string targetName,
|
|||
|
||||
return targetHash;
|
||||
}
|
||||
#endif
|
||||
|
||||
|
||||
/* Throw an exception if the given platform string is not supported by
|
||||
|
|
@ -182,54 +184,32 @@ static Hash computeDerived(Hash sourceHash, string targetName,
|
|||
static void checkPlatform(string platform)
|
||||
{
|
||||
if (platform != thisSystem)
|
||||
throw Error("a `" + platform +
|
||||
"' is required, but I am a `" + thisSystem + "'");
|
||||
throw Error(format("a `%1%' is required, but I am a `%2%'")
|
||||
% platform % thisSystem);
|
||||
}
|
||||
|
||||
|
||||
string printExpr(Expr e)
|
||||
string printTerm(ATerm t)
|
||||
{
|
||||
char * s = ATwriteToString(e);
|
||||
char * s = ATwriteToString(t);
|
||||
return s;
|
||||
}
|
||||
|
||||
|
||||
/* Throw an exception with an error message containing the given
|
||||
aterm. */
|
||||
static Error badTerm(const string & msg, Expr e)
|
||||
static Error badTerm(const format & f, ATerm t)
|
||||
{
|
||||
return Error(msg + ", in `" + printExpr(e) + "'");
|
||||
return Error(format("%1%, in `%2%'") % f.str() % printTerm(t));
|
||||
}
|
||||
|
||||
|
||||
Hash hashExpr(Expr e)
|
||||
Hash hashTerm(ATerm t)
|
||||
{
|
||||
return hashString(printExpr(e));
|
||||
return hashString(printTerm(t));
|
||||
}
|
||||
|
||||
|
||||
/* Evaluate an expression; the result must be a string. */
|
||||
static string evalString(Expr e)
|
||||
{
|
||||
e = whNormalise(e);
|
||||
char * s;
|
||||
if (ATmatch(e, "Str(<str>)", &s)) return s;
|
||||
else throw badTerm("string value expected", e);
|
||||
}
|
||||
|
||||
|
||||
#if 0
|
||||
/* Evaluate an expression; the result must be a value reference. */
|
||||
static Hash evalHash(Expr e)
|
||||
{
|
||||
e = evalValue(e);
|
||||
char * s;
|
||||
if (ATmatch(e, "Hash(<str>)", &s)) return parseHash(s);
|
||||
else throw badTerm("value reference expected", e);
|
||||
}
|
||||
#endif
|
||||
|
||||
|
||||
#if 0
|
||||
/* Evaluate a list of arguments into normal form. */
|
||||
void evalArgs(ATermList args, ATermList & argsNF, Environment & env)
|
||||
|
|
@ -262,225 +242,63 @@ void evalArgs(ATermList args, ATermList & argsNF, Environment & env)
|
|||
#endif
|
||||
|
||||
|
||||
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);
|
||||
}
|
||||
|
||||
|
||||
#if 0
|
||||
Expr evalValue(Expr e)
|
||||
{
|
||||
char * s;
|
||||
Expr eBuildPlatform, eProg, e2, e3, e4;
|
||||
ATermList args;
|
||||
|
||||
/* Value references. */
|
||||
if (ATmatch(e, "Hash(<str>)", &s)) {
|
||||
parseHash(s); /* i.e., throw exception if not valid */
|
||||
return e;
|
||||
}
|
||||
|
||||
/* External expression. */
|
||||
if (ATmatch(e, "Deref(<term>)", &e2)) {
|
||||
string fn = queryValuePath(evalHash(e2));
|
||||
ATerm e3 = ATreadFromNamedFile(fn.c_str());
|
||||
if (!e3) throw Error("reading aterm from " + fn);
|
||||
return evalValue(e3);
|
||||
}
|
||||
|
||||
/* Execution primitive. */
|
||||
|
||||
if (ATmatch(e, "Exec(<term>, <term>, [<list>])",
|
||||
&eBuildPlatform, &eProg, &args))
|
||||
{
|
||||
string buildPlatform = evalString(eBuildPlatform);
|
||||
|
||||
checkPlatform(buildPlatform);
|
||||
|
||||
Hash prog = evalHash(eProg);
|
||||
|
||||
Environment env;
|
||||
ATermList argsNF;
|
||||
evalArgs(args, argsNF, env);
|
||||
|
||||
Hash sourceHash = hashExpr(
|
||||
ATmake("Exec(Str(<str>), Hash(<str>), <term>)",
|
||||
buildPlatform.c_str(), ((string) prog).c_str(), argsNF));
|
||||
|
||||
/* Do we know a normal form for sourceHash? */
|
||||
Hash targetHash;
|
||||
string targetHashS;
|
||||
if (queryDB(nixDB, dbNFs, sourceHash, targetHashS)) {
|
||||
/* Yes. */
|
||||
targetHash = parseHash(targetHashS);
|
||||
debug("already built: " + (string) sourceHash
|
||||
+ " -> " + (string) targetHash);
|
||||
} else {
|
||||
/* No, so we compute one. */
|
||||
targetHash = computeDerived(sourceHash,
|
||||
(string) sourceHash + "-nf", buildPlatform, prog, env);
|
||||
}
|
||||
|
||||
return ATmake("Hash(<str>)", ((string) targetHash).c_str());
|
||||
}
|
||||
|
||||
/* Barf. */
|
||||
throw badTerm("invalid expression", e);
|
||||
}
|
||||
#endif
|
||||
|
||||
|
||||
Expr whNormalise(Expr e)
|
||||
{
|
||||
char * s;
|
||||
Expr e2, e3, e4, e5;
|
||||
|
||||
/* Normal forms. */
|
||||
if (ATmatch(e, "Str(<str>)", &s) ||
|
||||
ATmatch(e, "Bool(True)") ||
|
||||
ATmatch(e, "Bool(False)") ||
|
||||
ATmatch(e, "Lam(<str>, <term>)", &s, &e2) ||
|
||||
ATmatch(e, "File(<str>, <term>, <term>)", &s, &e2, &e3) ||
|
||||
ATmatch(e, "Derive(<term>, <term>, <term>, <term>)", &e2, &e3, &e4, &e5))
|
||||
return e;
|
||||
|
||||
/* Application. */
|
||||
if (ATmatch(e, "App(<term>, <term>)", &e2, &e3)) {
|
||||
e2 = whNormalise(e2);
|
||||
if (!ATmatch(e2, "Lam(<str>, <term>)", &s, &e4))
|
||||
throw badTerm("expecting lambda", e2);
|
||||
return whNormalise(substExpr(s, e3, e4));
|
||||
}
|
||||
|
||||
throw badTerm("invalid expression", e);
|
||||
}
|
||||
|
||||
|
||||
Expr dNormalise(Expr e)
|
||||
{
|
||||
e = whNormalise(e);
|
||||
/* !!! todo */
|
||||
return e;
|
||||
}
|
||||
|
||||
|
||||
Expr fNormalise(Expr e)
|
||||
{
|
||||
e = dNormalise(e);
|
||||
|
||||
char * s;
|
||||
Expr e2, e3;
|
||||
|
||||
if (ATmatch(e, "File(<str>, <term>, [<list>])", &s, &e2, &e3)) {
|
||||
|
||||
ATermList refs = (ATermList) e3, refs2 = ATempty;
|
||||
while (!ATisEmpty(refs)) {
|
||||
ATerm ref = ATgetFirst(refs);
|
||||
refs2 = ATinsert(refs2, fNormalise(ref));
|
||||
refs = ATgetNext(refs);
|
||||
}
|
||||
refs2 = ATreverse(refs2);
|
||||
|
||||
return ATmake("File(<str>, <term>, <term>)", s, e2, refs2);
|
||||
|
||||
}
|
||||
|
||||
else return e;
|
||||
}
|
||||
|
||||
|
||||
void writeContent(string path, Content content)
|
||||
{
|
||||
char * s;
|
||||
|
||||
if (ATmatch(content, "Regular(<str>)", &s)) {
|
||||
|
||||
int fd; /* !!! close on exception */
|
||||
fd = open(path.c_str(), O_CREAT | O_EXCL | O_WRONLY, 0666);
|
||||
if (fd == -1)
|
||||
throw SysError("creating file " + path);
|
||||
|
||||
int len = strlen(s);
|
||||
if (write(fd, s, len) != len)
|
||||
throw SysError("writing file " + path);
|
||||
|
||||
close(fd);
|
||||
}
|
||||
|
||||
else throw badTerm("ill-formed content", content);
|
||||
}
|
||||
|
||||
|
||||
struct RStatus
|
||||
{
|
||||
/* !!! the comparator of this hash should match the semantics of
|
||||
the file system */
|
||||
map<string, Hash> paths;
|
||||
// map<string, Hash> paths;
|
||||
};
|
||||
|
||||
|
||||
static void realise2(RStatus & status, Expr e)
|
||||
static void realise(RStatus & status, FState fs)
|
||||
{
|
||||
char * s;
|
||||
Content content;
|
||||
ATermList refs;
|
||||
|
||||
if (!ATmatch(e, "File(<str>, <term>, [<list>])", &s, &content, &refs))
|
||||
throw badTerm("not f-normalised", e);
|
||||
if (ATmatch(fs, "File(<str>, <term>, [<list>])", &s, &content, &refs)) {
|
||||
string path(s);
|
||||
|
||||
string path(s);
|
||||
if (path[0] != '/') throw Error("absolute path expected: " + path);
|
||||
|
||||
while (!ATisEmpty(refs)) {
|
||||
realise2(status, ATgetFirst(refs));
|
||||
refs = ATgetNext(refs);
|
||||
/* Realise referenced paths. */
|
||||
while (!ATisEmpty(refs)) {
|
||||
realise(status, ATgetFirst(refs));
|
||||
refs = ATgetNext(refs);
|
||||
}
|
||||
|
||||
if (!ATmatch(content, "Hash(<str>)", &s))
|
||||
throw badTerm("hash expected", content);
|
||||
Hash hash = parseHash(s);
|
||||
|
||||
/* Perhaps the path already exists and has the right hash? */
|
||||
if (pathExists(path)) {
|
||||
if (hash == hashPath(path)) {
|
||||
debug(format("path %1% already has hash %2%")
|
||||
% path % (string) hash);
|
||||
return;
|
||||
}
|
||||
|
||||
throw Error(format("path %1% exists, but does not have hash %2%")
|
||||
% path % (string) hash);
|
||||
}
|
||||
|
||||
/* Do we know a path with that hash? If so, copy it. */
|
||||
string path2 = queryFromStore(hash);
|
||||
copyFile(path2, path);
|
||||
}
|
||||
|
||||
writeContent(path, content);
|
||||
else if (ATmatch(fs, "Derive()")) {
|
||||
|
||||
|
||||
}
|
||||
|
||||
else throw badTerm("bad file system state expression", fs);
|
||||
}
|
||||
|
||||
|
||||
void realise(Expr e)
|
||||
void realiseFState(FState fs)
|
||||
{
|
||||
RStatus status;
|
||||
realise2(status, e);
|
||||
realise(status, fs);
|
||||
}
|
||||
|
|
|
|||
79
src/eval.hh
79
src/eval.hh
|
|
@ -10,14 +10,12 @@ extern "C" {
|
|||
using namespace std;
|
||||
|
||||
|
||||
/* \section{Abstract syntax of Nix expressions}
|
||||
/* \section{Abstract syntax of Nix file system state expressions}
|
||||
|
||||
An expression describes a (partial) state of the file system in a
|
||||
referentially transparent way. The operational effect of
|
||||
evaluating an expression is that the state described by the
|
||||
expression is realised.
|
||||
A Nix file system state expression, or FState, describes a
|
||||
(partial) state of the file system.
|
||||
|
||||
File : Path * Content * [Expr] -> Expr
|
||||
File : Path * Content * [FState] -> FState
|
||||
|
||||
File(path, content, refs) specifies a file object (its full path
|
||||
and contents), along with all file objects referenced by it (that
|
||||
|
|
@ -25,7 +23,7 @@ using namespace std;
|
|||
self-referential. This prevents us from having to deal with
|
||||
cycles.
|
||||
|
||||
Derive : String * Path * [Expr] * [Expr] * [Expr] -> Expr
|
||||
Derive : String * Path * [FState] * [Path] * [(String, String)] -> [FState]
|
||||
|
||||
Derive(platform, builder, ins, outs, env) specifies the creation of
|
||||
new file objects (in paths declared by `outs') by the execution of
|
||||
|
|
@ -33,14 +31,6 @@ using namespace std;
|
|||
place in a file system state given by `ins'. `env' specifies a
|
||||
mapping of strings to strings.
|
||||
|
||||
Str : String -> Expr
|
||||
|
||||
A string constant.
|
||||
|
||||
Tup : Expr * Expr -> Expr
|
||||
|
||||
Tuples of expressions.
|
||||
|
||||
[ !!! NOT IMPLEMENTED
|
||||
Regular : String -> Content
|
||||
Directory : [(String, Content)] -> Content
|
||||
|
|
@ -49,7 +39,11 @@ using namespace std;
|
|||
CHash : Hash -> Content
|
||||
|
||||
File content, given either in situ, or through an external reference
|
||||
to the file system or url-space decorated with a hash to preserve purity.
|
||||
to the file system or url-space decorated with a hash to preserve
|
||||
purity.
|
||||
|
||||
A FState expression is in {\em $f$-normal form} if all Derive nodes
|
||||
have been reduced to File nodes.
|
||||
|
||||
DISCUSSION: the idea is that a Regular/Directory is interchangeable
|
||||
with its CHash. This would appear to break referential
|
||||
|
|
@ -60,63 +54,20 @@ using namespace std;
|
|||
CHash, we should also export the file object referenced by that
|
||||
CHash.
|
||||
|
||||
|
||||
\section{Reduction rules}
|
||||
|
||||
...
|
||||
|
||||
|
||||
\section{Normals forms}
|
||||
|
||||
An expression is in {\em weak head normal form} if it is a lambda,
|
||||
a string or boolean value, or a File or Derive value.
|
||||
|
||||
An expression is in {\em $d$-normal form} if it matches the
|
||||
signature FExpr:
|
||||
|
||||
File : String * Content * [DExpr] -> DExpr
|
||||
Derive : String * Path * [Tup] * [Tup2] -> DExpr
|
||||
|
||||
Tup : Str * DExpr -> Tup
|
||||
Tup : Str * Str -> Tup
|
||||
|
||||
Tup : Str * Str -> Tup2
|
||||
|
||||
Str : String -> Str
|
||||
|
||||
These are Nix expressions in which the file system result of Derive
|
||||
expressions has not yet been computed. This is useful for, e.g.,
|
||||
querying dependencies.
|
||||
|
||||
An expression is in {\em $f$-normal form} if it matches the
|
||||
signature FExpr:
|
||||
|
||||
File : String * Content * [FExpr] -> FExpr
|
||||
|
||||
These are completely evaluated Nix expressions.
|
||||
|
||||
*/
|
||||
|
||||
typedef ATerm Expr;
|
||||
typedef ATerm FState;
|
||||
typedef ATerm Content;
|
||||
|
||||
|
||||
/* Expression normalisation. */
|
||||
Expr whNormalise(Expr e);
|
||||
Expr dNormalise(Expr e);
|
||||
Expr fNormalise(Expr e);
|
||||
|
||||
/* Realise a $f$-normalised expression in the file system. */
|
||||
void realise(Expr e);
|
||||
void realiseFState(FState fs);
|
||||
|
||||
/* Return a canonical textual representation of an expression. */
|
||||
string printExpr(Expr e);
|
||||
string printTerm(ATerm t);
|
||||
|
||||
/* Perform variable substitution. */
|
||||
Expr substExpr(string x, Expr rep, Expr e);
|
||||
|
||||
/* Hash an expression. */
|
||||
Hash hashExpr(Expr e);
|
||||
/* Hash an aterm. */
|
||||
Hash hashTerm(ATerm t);
|
||||
|
||||
|
||||
#endif /* !__EVAL_H */
|
||||
|
|
|
|||
|
|
@ -6,7 +6,7 @@ string dbRefs = "refs";
|
|||
string dbNFs = "nfs";
|
||||
string dbNetSources = "netsources";
|
||||
|
||||
string nixValues = "/UNINIT";
|
||||
string nixStore = "/UNINIT";
|
||||
string nixLogDir = "/UNINIT";
|
||||
string nixDB = "/UNINIT";
|
||||
|
||||
|
|
|
|||
|
|
@ -8,15 +8,10 @@ using namespace std;
|
|||
|
||||
/* Database names. */
|
||||
|
||||
/* dbRefs :: Hash -> FileName
|
||||
/* dbRefs :: Hash -> Path
|
||||
|
||||
Maintains a mapping from hashes to filenames within the NixValues
|
||||
directory. This mapping is for performance only; it can be
|
||||
reconstructed unambiguously. The reason is that names in this
|
||||
directory are not printed hashes but also might carry some
|
||||
descriptive element (e.g., "aterm-2.0-ae749a..."). Without this
|
||||
mapping, looking up a value would take O(n) time because we would
|
||||
need to read the entire directory. */
|
||||
Maintains a mapping from hashes to paths. This is what we use to
|
||||
resolve CHash(hash) content descriptors. */
|
||||
extern string dbRefs;
|
||||
|
||||
/* dbNFs :: Hash -> Hash
|
||||
|
|
@ -45,11 +40,11 @@ extern string dbNetSources;
|
|||
|
||||
/* Path names. */
|
||||
|
||||
/* nixValues is the directory where all Nix values (both files and
|
||||
directories, and both normal and non-normal forms) live. */
|
||||
extern string nixValues;
|
||||
/* nixStore is the directory where we generally store atomic and
|
||||
derived files. */
|
||||
extern string nixStore;
|
||||
|
||||
/* nixLogDir is the directory where we log evaluations. */
|
||||
/* nixLogDir is the directory where we log various operations. */
|
||||
extern string nixLogDir;
|
||||
|
||||
/* nixDB is the file name of the Berkeley DB database where we
|
||||
|
|
|
|||
|
|
@ -14,7 +14,7 @@ Hash::Hash()
|
|||
}
|
||||
|
||||
|
||||
bool Hash::operator == (Hash & h2)
|
||||
bool Hash::operator == (Hash h2)
|
||||
{
|
||||
for (unsigned int i = 0; i < hashSize; i++)
|
||||
if (hash[i] != h2.hash[i]) return false;
|
||||
|
|
@ -22,7 +22,7 @@ bool Hash::operator == (Hash & h2)
|
|||
}
|
||||
|
||||
|
||||
bool Hash::operator != (Hash & h2)
|
||||
bool Hash::operator != (Hash h2)
|
||||
{
|
||||
return !(*this == h2);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -17,10 +17,10 @@ struct Hash
|
|||
Hash();
|
||||
|
||||
/* Check whether two hash are equal. */
|
||||
bool operator == (Hash & h2);
|
||||
bool operator == (Hash h2);
|
||||
|
||||
/* Check whether two hash are not equal. */
|
||||
bool operator != (Hash & h2);
|
||||
bool operator != (Hash h2);
|
||||
|
||||
/* Convert a hash code into a hexadecimal representation. */
|
||||
operator string() const;
|
||||
|
|
|
|||
36
src/test.cc
36
src/test.cc
|
|
@ -11,20 +11,16 @@
|
|||
#include "globals.hh"
|
||||
|
||||
|
||||
typedef Expr (* Normaliser) (Expr);
|
||||
|
||||
|
||||
void eval(Normaliser n, Expr e)
|
||||
void realise(FState fs)
|
||||
{
|
||||
e = n(e);
|
||||
cout << (string) hashExpr(e) << ": " << printExpr(e) << endl;
|
||||
realiseFState(fs);
|
||||
}
|
||||
|
||||
|
||||
void evalFail(Normaliser n, Expr e)
|
||||
void realiseFail(FState fs)
|
||||
{
|
||||
try {
|
||||
e = n(e);
|
||||
realiseFState(fs);
|
||||
abort();
|
||||
} catch (Error e) {
|
||||
cout << "error (expected): " << e.what() << endl;
|
||||
|
|
@ -96,7 +92,7 @@ void runTests()
|
|||
string testDir = absPath("scratch");
|
||||
cout << testDir << endl;
|
||||
|
||||
nixValues = testDir;
|
||||
nixStore = testDir;
|
||||
nixLogDir = testDir;
|
||||
nixDB = testDir + "/db";
|
||||
|
||||
|
|
@ -104,6 +100,7 @@ void runTests()
|
|||
|
||||
/* Expression evaluation. */
|
||||
|
||||
#if 0
|
||||
eval(whNormalise,
|
||||
ATmake("Str(\"Hello World\")"));
|
||||
eval(whNormalise,
|
||||
|
|
@ -138,10 +135,27 @@ void runTests()
|
|||
eval(fNormalise, e2);
|
||||
|
||||
realise(e2);
|
||||
#endif
|
||||
|
||||
Hash builder1h;
|
||||
string builder1fn;
|
||||
addToStore("./test-builder-1.sh", builder1fn, builder1h);
|
||||
|
||||
FState fs1 = ATmake(
|
||||
"File(<str>, Hash(<str>), [])",
|
||||
builder1fn.c_str(),
|
||||
((string) builder1h).c_str());
|
||||
realiseFState(fs1);
|
||||
realiseFState(fs1);
|
||||
|
||||
FState fs2 = ATmake(
|
||||
"File(<str>, Hash(<str>), [])",
|
||||
(builder1fn + "_bla").c_str(),
|
||||
((string) builder1h).c_str());
|
||||
realiseFState(fs2);
|
||||
realiseFState(fs2);
|
||||
|
||||
#if 0
|
||||
Hash builder1 = addValue("./test-builder-1.sh");
|
||||
|
||||
Expr e1 = ATmake("Exec(Str(<str>), Hash(<str>), [])",
|
||||
thisSystem.c_str(), ((string) builder1).c_str());
|
||||
|
||||
|
|
|
|||
|
|
@ -78,7 +78,7 @@ void deletePath(string path)
|
|||
}
|
||||
|
||||
|
||||
void debug(string s)
|
||||
void debug(const format & f)
|
||||
{
|
||||
cerr << "debug: " << s << endl;
|
||||
cerr << format("debug: %1%\n") % f.str();
|
||||
}
|
||||
|
|
|
|||
|
|
@ -7,7 +7,10 @@
|
|||
|
||||
#include <unistd.h>
|
||||
|
||||
#include <boost/format.hpp>
|
||||
|
||||
using namespace std;
|
||||
using namespace boost;
|
||||
|
||||
|
||||
class Error : public exception
|
||||
|
|
@ -16,7 +19,7 @@ protected:
|
|||
string err;
|
||||
public:
|
||||
Error() { }
|
||||
Error(string _err) { err = _err; }
|
||||
Error(format f) { err = f.str(); }
|
||||
~Error() throw () { }
|
||||
const char * what() const throw () { return err.c_str(); }
|
||||
};
|
||||
|
|
@ -59,7 +62,7 @@ string baseNameOf(string path);
|
|||
void deletePath(string path);
|
||||
|
||||
|
||||
void debug(string s);
|
||||
void debug(const format & f);
|
||||
|
||||
|
||||
#endif /* !__UTIL_H */
|
||||
|
|
|
|||
|
|
@ -34,7 +34,7 @@ struct CopySource : RestoreSource
|
|||
};
|
||||
|
||||
|
||||
static void copyFile(string src, string dst)
|
||||
void copyFile(string src, string dst)
|
||||
{
|
||||
/* Unfortunately C++ doesn't support coprocedures, so we have no
|
||||
nice way to chain CopySink and CopySource together. Instead we
|
||||
|
|
@ -83,33 +83,25 @@ static void copyFile(string src, string dst)
|
|||
}
|
||||
|
||||
|
||||
static string absValuePath(string s)
|
||||
void addToStore(string srcPath, string & dstPath, Hash & hash)
|
||||
{
|
||||
return nixValues + "/" + s;
|
||||
}
|
||||
srcPath = absPath(srcPath);
|
||||
|
||||
hash = hashPath(srcPath);
|
||||
|
||||
Hash addValue(string path)
|
||||
{
|
||||
path = absPath(path);
|
||||
|
||||
Hash hash = hashPath(path);
|
||||
|
||||
string name;
|
||||
if (queryDB(nixDB, dbRefs, hash, name)) {
|
||||
string path;
|
||||
if (queryDB(nixDB, dbRefs, hash, path)) {
|
||||
debug((string) hash + " already known");
|
||||
return hash;
|
||||
dstPath = path;
|
||||
return;
|
||||
}
|
||||
|
||||
string baseName = baseNameOf(path);
|
||||
string baseName = baseNameOf(srcPath);
|
||||
dstPath = nixStore + "/" + (string) hash + "-" + baseName;
|
||||
|
||||
string targetName = (string) hash + "-" + baseName;
|
||||
copyFile(srcPath, dstPath);
|
||||
|
||||
copyFile(path, absValuePath(targetName));
|
||||
|
||||
setDB(nixDB, dbRefs, hash, targetName);
|
||||
|
||||
return hash;
|
||||
setDB(nixDB, dbRefs, hash, dstPath);
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -135,28 +127,28 @@ string fetchURL(string url)
|
|||
#endif
|
||||
|
||||
|
||||
void deleteValue(Hash hash)
|
||||
void deleteFromStore(Hash hash)
|
||||
{
|
||||
string name;
|
||||
if (queryDB(nixDB, dbRefs, hash, name)) {
|
||||
string fn = absValuePath(name);
|
||||
string fn;
|
||||
if (queryDB(nixDB, dbRefs, hash, fn)) {
|
||||
string prefix = nixStore + "/";
|
||||
if (string(fn, prefix.size()) != prefix)
|
||||
throw Error("path " + fn + " is not in the store");
|
||||
deletePath(fn);
|
||||
delDB(nixDB, dbRefs, hash);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/* !!! bad name, "query" implies no side effect => getValuePath() */
|
||||
string queryValuePath(Hash hash)
|
||||
string queryFromStore(Hash hash)
|
||||
{
|
||||
bool checkedNet = false;
|
||||
|
||||
while (1) {
|
||||
|
||||
string name, url;
|
||||
string fn, url;
|
||||
|
||||
if (queryDB(nixDB, dbRefs, hash, name)) {
|
||||
string fn = absValuePath(name);
|
||||
if (queryDB(nixDB, dbRefs, hash, fn)) {
|
||||
|
||||
/* Verify that the file hasn't changed. !!! race !!! slow */
|
||||
if (hashPath(fn) != hash)
|
||||
|
|
|
|||
|
|
@ -8,21 +8,17 @@
|
|||
using namespace std;
|
||||
|
||||
|
||||
/* Copy a value to the nixValues directory and register it in dbRefs.
|
||||
void copyFile(string src, string dst);
|
||||
|
||||
/* Copy a file to the nixStore directory and register it in dbRefs.
|
||||
Return the hash code of the value. */
|
||||
Hash addValue(string pathName);
|
||||
void addToStore(string srcPath, string & dstPath, Hash & hash);
|
||||
|
||||
/* Delete a value from the nixStore directory. */
|
||||
void deleteFromStore(Hash hash);
|
||||
|
||||
/* Delete a value from the nixValues directory. */
|
||||
void deleteValue(Hash hash);
|
||||
|
||||
|
||||
/* Obtain the path of a value with the given hash. If a file with
|
||||
that hash is known to exist in the local file system (as indicated
|
||||
by the dbRefs database), we use that. Otherwise, we attempt to
|
||||
fetch it from the network (using dbNetSources). We verify that the
|
||||
file has the right hash. */
|
||||
string queryValuePath(Hash hash);
|
||||
/* !!! */
|
||||
string queryFromStore(Hash hash);
|
||||
|
||||
|
||||
#endif /* !__VALUES_H */
|
||||
|
|
|
|||
Loading…
Reference in a new issue