maurice/snix
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

* Flags to indicate how values are specified on the command line

Browse source 
(--hash, --file, --name).
This commit is contained in:
Eelco Dolstra 2003-06-20 14:11:31 +00:00
parent 5079ccb455
commit 85effedca3
4 changed files with 137 additions and 64 deletions
Download patch file Download diff file Expand all files Collapse all files

176
src/nix.cc
View file

@ -11,34 +11,94 @@
typedef void (* Operation) (Strings opFlags, Strings opArgs);
/* Parse a supposed value argument. This can be a hash (the simple
case), a symbolic name (in which case we do a lookup to obtain the
hash), or a file name (which we import to obtain the hash). Note
that in order to disambiguate between symbolic names and file
names, a file name should contain at least one `/'. */
Hash parseValueArg(string s)
{
try {
return parseHash(s);
} catch (BadRefError e) { };
typedef enum { atpHash, atpName, atpPath, atpUnknown } ArgType;
if (s.find('/') != string::npos) {
return addValue(s);
} else {
throw Error("not implemented");
static ArgType argType = atpUnknown;
/* Nix syntax:
nix [OPTIONS...] [ARGUMENTS...]
Operations:
--evaluate / -e: evaluate values
--delete / -d: delete values
--query / -q: query stored values
--add: add values
--verify: verify Nix structures
--dump: dump a file or value
--init: initialise the Nix database
--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. */
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");
}
/* Evaluate values. */
static void opEvaluate(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 = parseValueArg(*it);
Hash hash;
if (argType == atpHash)
hash = parseHash(*it);
else if (argType == atpName)
throw Error("not implemented");
else if (argType == atpPath)
hash = addValue(*it);
Expr e = ATmake("Deref(Hash(<str>))", ((string) hash).c_str());
cerr << printExpr(evalValue(e)) << endl;
}
@ -47,6 +107,8 @@ static void opEvaluate(Strings opFlags, Strings opArgs)
static void opDelete(Strings opFlags, Strings opArgs)
{
getArgType(opFlags);
cerr << "delete!\n";
}
@ -55,6 +117,7 @@ static void opDelete(Strings opFlags, Strings opArgs)
those values. */
static void opAdd(Strings opFlags, Strings opArgs)
{
getArgType(opFlags);
if (!opFlags.empty()) throw UsageError("unknown flag");
for (Strings::iterator it = opArgs.begin();
@ -78,11 +141,22 @@ struct StdoutSink : DumpSink
/* Dump a value to standard output */
static void opDump(Strings opFlags, Strings opArgs)
{
getArgType(opFlags);
if (!opFlags.empty()) throw UsageError("unknown flag");
if (opArgs.size() != 1) throw UsageError("only one argument allowed");
StdoutSink sink;
dumpPath(opArgs[0], 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(*opArgs.begin(), sink);
}
@ -96,59 +170,43 @@ static void opInit(Strings opFlags, Strings opArgs)
}
/* Nix syntax:
nix [OPTIONS...] [ARGUMENTS...]
Operations:
--evaluate / -e: evaluate values
--delete / -d: delete values
--query / -q: query stored values
--add: add values
--verify: verify Nix structures
--dump: dump a file or value
--init: initialise the Nix database
--version: output version information
--help: display help
Operations that work on values accept the hash code of a value, the
symbolic name of a value, or a file name of a external value that
will be added prior to the operation.
Query suboptions:
Selection:
--all / -a: query all stored values, otherwise given values
Information:
--info / -i: general value information
Options:
--verbose / -v: verbose operation
*/
/* Initialize, process arguments, and dispatch to the right
operation. */
void run(Strings::iterator argCur, Strings::iterator argEnd)
void run(int argc, char * * argv)
{
Strings opFlags, opArgs;
Operation op = 0;
/* Setup Nix paths. */
nixValues = NIX_VALUES_DIR;
nixLogDir = NIX_LOG_DIR;
nixDB = (string) NIX_STATE_DIR + "/nixstate.db";
/* Put the arguments in a vector. */
Strings args;
while (argc--) args.push_back(*argv++);
args.erase(args.begin());
/* Expand compound dash options (i.e., `-qlf' -> `-q -l -f'). */
for (Strings::iterator it = args.begin();
it != args.end(); )
{
string arg = *it;
if (arg.length() > 2 && arg[0] == '-' && arg[1] != '-') {
for (unsigned int i = 1; i < arg.length(); i++)
args.insert(it, (string) "-" + arg[i]);
it = args.erase(it);
} else it++;
}
Strings opFlags, opArgs;
Operation op = 0;
/* Scan the arguments; find the operation, set global flags, put
all other flags in a list, and put all other arguments in
another list. */
while (argCur != argEnd) {
string arg = *argCur++;
for (Strings::iterator it = args.begin();
it != args.end(); it++)
{
string arg = *it;
Operation oldOp = op;
@ -184,9 +242,7 @@ int main(int argc, char * * argv)
ATinit(argc, argv, &bottomOfStack);
try {
Strings args;
while (argc--) args.push_back(*argv++);
run(args.begin() + 1, args.end());
run(argc, argv);
} catch (UsageError & e) {
cerr << "error: " << e.what() << endl
<< "Try `nix --help' for more information.\n";