tvl-depot/src/libstore/normalise.hh
Eelco Dolstra c8d3882cdc * True parallel builds. Nix can now run as many build jobs in
parallel as possible (similar to GNU Make's `-j' switch).  This is
  useful on SMP systems, but it is especially useful for doing builds
  on multiple machines.  The idea is that a large derivation is
  initiated on one master machine, which then distributes
  sub-derivations to any number of slave machines.  This should not
  happen synchronously or in lock-step, so the master must be capable
  of dealing with multiple parallel build jobs.  We now have the
  infrastructure to support this.

  TODO: substitutes are currently broken.
2004-05-11 18:05:44 +00:00

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C++

#ifndef __NORMALISE_H
#define __NORMALISE_H
#include "storeexpr.hh"
/* Normalise a store expression. That is, if the expression is a
derivation, a path containing an equivalent closure expression is
returned. This requires that the derivation is performed, unless a
successor is known. */
Path normaliseStoreExpr(const Path & nePath);
/* Realise a closure store expression in the file system.
The pending paths are those that are already being realised. This
prevents infinite recursion for paths realised through a substitute
(since when we build the substitute, we would first try to realise
its output paths through substitutes... kaboom!). */
void realiseClosure(const Path & nePath);
/* Ensure that a path exists, possibly by instantiating it by
realising a substitute. */
void ensurePath(const Path & path);
/* Read a store expression, after ensuring its existence through
ensurePath(). */
StoreExpr storeExprFromPath(const Path & path);
/* Get the list of root (output) paths of the given store
expression. */
PathSet storeExprRoots(const Path & nePath);
/* Get the list of paths that are required to realise the given store
expression. For a derive expression, this is the union of
requisites of the inputs; for a closure expression, it is the path
of each element in the closure. If `includeExprs' is true, include
the paths of the store expressions themselves. If
`includeSuccessors' is true, include the requisites of
successors. */
PathSet storeExprRequisites(const Path & nePath,
bool includeExprs, bool includeSuccessors);
/* Return the list of the paths of all known store expressions whose
output paths are completely contained in the set `outputs'. */
PathSet findGenerators(const PathSet & outputs);
#endif /* !__NORMALISE_H */