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#ifndef __GLOBALS_H
#define __GLOBALS_H
#include <string>
#include "db.hh"
using namespace std;
extern Database nixDB;
/* Database tables. */
/* dbValidPaths :: Path -> ()
The existence of a key $p$ indicates that path $p$ is valid (that
is, produced by a succesful build). */
extern TableId dbValidPaths;
/* dbSuccessors :: Path -> Path
Each pair $(p_1, p_2)$ in this mapping records the fact that the
Nix expression stored at path $p_1$ has a successor expression
stored at path $p_2$.
Note that a term $y$ is a successor of $x$ iff there exists a
sequence of rewrite steps that rewrites $x$ into $y$.
*/
extern TableId dbSuccessors;
/* dbSuccessorsRev :: Path -> [Path]
The reverse mapping of dbSuccessors (i.e., it stores the
predecessors of a Nix expression).
*/
extern TableId dbSuccessorsRev;
/* dbSubstitutes :: Path -> [Path]
Each pair $(p, [ps])$ tells Nix that it can realise any of the
Nix expressions stored at paths $ps$ to produce a path $p$.
The main purpose of this is for distributed caching of derivates.
One system can compute a derivate and put it on a website (as a Nix
archive), for instance, and then another system can register a
substitute for that derivate. The substitute in this case might be
a Nix expression that fetches the Nix archive.
*/
extern TableId dbSubstitutes;
/* dbSubstitutesRev :: Path -> [Path]
The reverse mapping of dbSubstitutes.
*/
extern TableId dbSubstitutesRev;
/* Path names. */
/* nixStore is the directory where we generally store atomic and
derived files. */
extern string nixStore;
extern string nixDataDir; /* !!! fix */
/* nixLogDir is the directory where we log various operations. */
extern string nixLogDir;
/* nixDBPath is the path name of our Berkeley DB environment. */
extern string nixDBPath;
/* Misc. global flags. */
/* Whether to keep temporary directories of failed builds. */
extern bool keepFailed;
/* Open the database environment. */
void openDB();
/* Create the required database tables. */
void initDB();
#endif /* !__GLOBALS_H */
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