lix/src/nix.cc
2003-07-07 07:43:58 +00:00

269 lines
6.5 KiB
C++

#include <iostream>
#include "globals.hh"
#include "store.hh"
#include "fstate.hh"
#include "archive.hh"
#include "shared.hh"
typedef void (* Operation) (Strings opFlags, Strings opArgs);
typedef enum { atpHash, atpName, atpPath, atpUnknown } ArgType;
static ArgType argType = atpUnknown;
/* Nix syntax:
nix [OPTIONS...] [ARGUMENTS...]
Operations:
--realise / -r: realise values
--delete / -d: delete values
--query / -q: query stored values
--add: add values
--dump: dump a value as a Nix archive
--restore: restore a value from a Nix archive
--init: initialise the Nix database
--verify: verify Nix structures
--version: output version information
--help: display help
Source selection for operations that work on values:
--file / -f: by file name
--hash / -h: by hash
--name / -n: by symbolic name
Query suboptions:
Selection:
--all / -a: query all stored values, otherwise given values
Information:
--info / -i: general value information
Options:
--verbose / -v: verbose operation
*/
/* Parse the `-f' / `-h' / `-n' flags, i.e., the type of value
arguments. These flags are deleted from the referenced vector. */
static void getArgType(Strings & flags)
{
for (Strings::iterator it = flags.begin();
it != flags.end(); )
{
string arg = *it;
ArgType tp;
if (arg == "--hash" || arg == "-h")
tp = atpHash;
else if (arg == "--name" || arg == "-n")
tp = atpName;
else if (arg == "--file" || arg == "-f")
tp = atpPath;
else {
it++;
continue;
}
if (argType != atpUnknown)
throw UsageError("only one argument type specified may be specified");
argType = tp;
it = flags.erase(it);
}
if (argType == atpUnknown)
throw UsageError("argument type not specified");
}
/* Realise values. */
static void opRealise(Strings opFlags, Strings opArgs)
{
getArgType(opFlags);
if (!opFlags.empty()) throw UsageError("unknown flag");
for (Strings::iterator it = opArgs.begin();
it != opArgs.end(); it++)
{
Hash hash;
if (argType == atpHash)
hash = parseHash(*it);
else if (argType == atpName)
throw Error("not implemented");
else if (argType == atpPath) {
string path;
addToStore(*it, path, hash);
}
FState fs = ATmake("Include(<str>)", ((string) hash).c_str());
realiseFState(fs);
}
}
static void opDelete(Strings opFlags, Strings opArgs)
{
#if 0
getArgType(opFlags);
if (!opFlags.empty()) throw UsageError("unknown flag");
for (Strings::iterator it = opArgs.begin();
it != opArgs.end(); it++)
{
Hash hash;
if (argType == atpHash)
hash = parseHash(*it);
else if (argType == atpName)
throw Error("not implemented");
else
throw Error("invalid argument type");
deleteValue(hash);
}
#endif
}
/* Add values to the Nix values directory and print the hashes of
those values. */
static void opAdd(Strings opFlags, Strings opArgs)
{
getArgType(opFlags);
if (!opFlags.empty()) throw UsageError("unknown flag");
for (Strings::iterator it = opArgs.begin();
it != opArgs.end(); it++)
{
string path;
Hash hash;
addToStore(*it, path, hash);
cout << format("%1% %2%\n") % (string) hash % path;
}
}
/* A sink that writes dump output to stdout. */
struct StdoutSink : DumpSink
{
virtual void operator ()
(const unsigned char * data, unsigned int len)
{
if (write(STDOUT_FILENO, (char *) data, len) != (ssize_t) len)
throw SysError("writing to stdout");
}
};
/* Dump a value as a Nix archive. The archive is written to standard
output. */
static void opDump(Strings opFlags, Strings opArgs)
{
#if 0
getArgType(opFlags);
if (!opFlags.empty()) throw UsageError("unknown flag");
if (opArgs.size() != 1) throw UsageError("only one argument allowed");
StdoutSink sink;
string arg = *opArgs.begin();
string path;
if (argType == atpHash)
path = queryValuePath(parseHash(arg));
else if (argType == atpName)
throw Error("not implemented");
else if (argType == atpPath)
path = arg;
dumpPath(path, sink);
#endif
}
/* A source that read restore intput to stdin. */
struct StdinSource : RestoreSource
{
virtual void operator () (const unsigned char * data, unsigned int len)
{
ssize_t res = read(STDIN_FILENO, (char *) data, len);
if (res == -1)
throw SysError("reading from stdin");
if (res != (ssize_t) len)
throw Error("not enough data available on stdin");
}
};
/* Restore a value from a Nix archive. The archive is written to
standard input. */
static void opRestore(Strings opFlags, Strings opArgs)
{
if (!opFlags.empty()) throw UsageError("unknown flag");
if (opArgs.size() != 1) throw UsageError("only one argument allowed");
StdinSource source;
restorePath(*opArgs.begin(), source);
}
/* Initialise the Nix databases. */
static void opInit(Strings opFlags, Strings opArgs)
{
if (!opFlags.empty()) throw UsageError("unknown flag");
if (!opArgs.empty())
throw UsageError("--init does not have arguments");
initDB();
}
/* Scan the arguments; find the operation, set global flags, put all
other flags in a list, and put all other arguments in another
list. */
void run(Strings args)
{
Strings opFlags, opArgs;
Operation op = 0;
for (Strings::iterator it = args.begin();
it != args.end(); it++)
{
string arg = *it;
Operation oldOp = op;
if (arg == "--realise" || arg == "-r")
op = opRealise;
else if (arg == "--delete" || arg == "-d")
op = opDelete;
else if (arg == "--add")
op = opAdd;
else if (arg == "--dump")
op = opDump;
else if (arg == "--restore")
op = opRestore;
else if (arg == "--init")
op = opInit;
else if (arg[0] == '-')
opFlags.push_back(arg);
else
opArgs.push_back(arg);
if (oldOp && oldOp != op)
throw UsageError("only one operation may be specified");
}
if (!op) throw UsageError("no operation specified");
op(opFlags, opArgs);
}
string programId = "nix";