ref: d916a4c3823f55227ffae35738c2497256e307b5
dir: /appl/cmd/sh/mload.b/
implement Sh;
include "sys.m";
sys: Sys;
include "draw.m";
include "sh.m";
sh: Sh;
myself: Shellbuiltin;
mysh: Sh;
Namespace: adt {
name: string;
madecmd: array of int;
mods: list of (string, Shellbuiltin);
builtins: array of list of (string, Shellbuiltin);
};
Builtin, Sbuiltin: con iota;
namespaces: list of ref Namespace;
pending: list of (string, int, Shellbuiltin);
lock: chan of int;
BUILTINPATH: con "/dis/sh";
initbuiltin(c: ref Sh->Context, shmod: Sh): string
{
sys = load Sys Sys->PATH;
sh = shmod;
mysh = load Sh "$self";
myself = load Shellbuiltin "$self";
sh->c.addbuiltin("mload", myself);
sh->c.addbuiltin("munload", myself);
lock = chan[1] of int;
return nil;
}
runbuiltin(ctxt: ref Sh->Context, nil: Sh,
argv: list of ref Sh->Listnode, last: int): string
{
cmd := (hd argv).word;
case cmd {
"mload" or "munload" =>
if(tl argv == nil)
ctxt.fail("usage", "usage: "+cmd+" name [module...]");
# by doing this lock, we're relying on modules not to invoke a command
# in initbuiltin that calls back into mload. since they shouldn't be running
# any commands in initbuiltin anyway, this seems like a reasonable assumption.
lock <-= 1;
{
name := (hd tl argv).word;
for(argv = tl tl argv; argv != nil; argv = tl argv){
if((hd argv).cmd != nil)
ctxt.fail("usage", "usage: "+cmd+" namespace [module...]");
if(cmd == "mload")
mload(ctxt, name, (hd argv).word);
else
munload(ctxt, name, (hd argv).word);
}
}exception{
"fail:*" =>
<-lock;
raise;
}
<-lock;
return nil;
* =>
if(len argv < 2)
ctxt.fail("usage", sys->sprint("usage: %s command", (hd argv).word));
b := lookup(ctxt, (hd argv).word, (hd tl argv).word, Builtin, nil);
return b->runbuiltin(ctxt, mysh, tl argv, last);
}
}
mload(ctxt: ref Sh->Context, name, modname: string): string
{
ns := nslookup(name);
if(ns == nil){
ns = ref Namespace(name, array[2] of {* => 0}, nil, array[2] of list of (string, Shellbuiltin));
namespaces = ns :: namespaces;
}
for(nsm := ns.mods; nsm != nil; nsm = tl nsm)
if((hd nsm).t0 == modname)
return nil;
path := modname;
if (len path < 4 || path[len path-4:] != ".dis")
path += ".dis";
if (path[0] != '/' && path[0:2] != "./")
path = BUILTINPATH + "/" + path;
mod := load Shellbuiltin path;
if (mod == nil)
ctxt.fail("bad module", sys->sprint("load: cannot load %s: %r", path));
s := mod->initbuiltin(ctxt, mysh);
if(s != nil){
munload(ctxt, name, modname);
pending = nil;
ctxt.fail("init", "mload: init "+modname+" failed: "+s);
}
mod = mod->getself();
ns.mods = (modname, mod) :: ns.mods;
for(; pending != nil; pending = tl pending){
(cmd, which, pmod) := hd pending;
if(pmod != mod)
sys->fprint(sys->fildes(2), "mload: unexpected module when loading %#q", name);
else
lookup(ctxt, name, cmd, which, mod);
}
return nil;
}
munload(ctxt: ref Sh->Context, name, modname: string): string
{
ns := nslookup(name);
if(ns == nil){
sys->fprint(sys->fildes(2), "munload: no such namespace %#q\n", name);
return "fail";
}
nm: list of (string, Shellbuiltin);
mod: Shellbuiltin;
for(m := ns.mods; m != nil; m = tl m)
if((hd m).t0 == modname)
mod = (hd m).t1;
else
nm = hd m :: nm;
if(mod == nil){
sys->fprint(sys->fildes(2), "munload: no such module %#q\n", modname);
return "fail";
}
ns.mods = nm;
for(i := 0; i < 2; i++){
nb: list of (string, Shellbuiltin) = nil;
for(b := ns.builtins[i]; b != nil; b = tl b)
if((hd b).t1 != mod)
nb = hd b :: nb;
ns.builtins[i] = nb;
if(ns.builtins[i] == nil){
if(i == Builtin)
sh->ctxt.removebuiltin(name, myself);
else
sh->ctxt.removesbuiltin(name, myself);
}
}
return nil;
}
runsbuiltin(ctxt: ref Sh->Context, nil: Sh,
argv: list of ref Sh->Listnode): list of ref Sh->Listnode
{
if(len argv < 2)
ctxt.fail("usage", sys->sprint("usage: %s command", (hd argv).word));
b := lookup(ctxt, (hd argv).word, (hd tl argv).word, Sbuiltin, nil);
return b->runsbuiltin(ctxt, mysh, tl argv);
}
searchns(mod: Shellbuiltin): string
{
for(m := namespaces; m != nil; m = tl m)
for(b := (hd m).mods; b != nil; b = tl b)
if((hd b).t1 == mod)
return (hd m).name;
return nil;
}
lookup(ctxt: ref Sh->Context, name, cmd: string, which: int, sb: Shellbuiltin): Shellbuiltin
{
for(m := namespaces; m != nil; m = tl m)
if((hd m).name == name)
break;
if(m == nil)
ctxt.fail("unknown", sys->sprint("unknown namespace %q", name));
ns := hd m;
for(b := ns.builtins[which]; b != nil; b = tl b)
if((hd b).t0 == cmd)
break;
if(b == nil){
if(sb != nil){
ns.builtins[which] = (cmd, sb) :: ns.builtins[which];
if(!ns.madecmd[which]){
if(which == Builtin)
sh->ctxt.addbuiltin(name, myself);
else
sh->ctxt.addsbuiltin(name, myself);
ns.madecmd[which] = 1;
}
return sb;
}
ctxt.fail("unknown cmd", sys->sprint("unknown command %q", cmd));
}
return (hd b).t1;
}
Context.addbuiltin(c: self ref Context, modname: string, mod: Shellbuiltin)
{
name := searchns(mod);
if(name == nil)
pending = (modname, Builtin, mod) :: pending;
else
lookup(c, name, modname, Builtin, mod);
}
Context.addsbuiltin(c: self ref Context, modname: string, mod: Shellbuiltin)
{
name := searchns(mod);
if(name == nil)
pending = (modname, Sbuiltin, mod) :: pending;
else
lookup(c, name, modname, Sbuiltin, mod);
}
Context.removebuiltin(c: self ref Context, nil: string, nil: Shellbuiltin)
{
c.fail("nope", "mload: remove builtin not implemented");
}
Context.removesbuiltin(c: self ref Context, nil: string, nil: Shellbuiltin)
{
c.fail("nope", "mload: remove sbuiltin not implemented");
}
Context.addmodule(nil: self ref Context, name: string, nil: Shellbuiltin)
{
sys->fprint(sys->fildes(2), "mload: addmodule not allowed (%s)\n", name);
}
nslookup(name: string): ref Namespace
{
for(m := namespaces; m != nil; m = tl m)
if((hd m).name == name)
return hd m;
return nil;
}
whatis(nil: ref Sh->Context, nil: Sh, nil: string, nil: int): string
{
return nil;
}
getself(): Shellbuiltin
{
return myself;
}
initialise()
{
return sh->initialise();
}
init(ctxt: ref Draw->Context, argv: list of string)
{
return sh->init(ctxt, argv);
}
system(ctxt: ref Draw->Context, cmd: string): string
{
return sh->system(ctxt, cmd);
}
run(ctxt: ref Draw->Context, argv: list of string): string
{
return sh->run(ctxt, argv);
}
parse(s: string): (ref Cmd, string)
{
return sh->parse(s);
}
cmd2string(c: ref Cmd): string
{
return sh->cmd2string(c);
}
list2stringlist(nl: list of ref Listnode): list of string
{
return sh->list2stringlist(nl);
}
stringlist2list(sl: list of string): list of ref Listnode
{
return sh->stringlist2list(sl);
}
quoted(val: list of ref Listnode, quoteblocks: int): string
{
return sh->quoted(val, quoteblocks);
}
Context.new(drawcontext: ref Draw->Context): ref Context
{
return sh->Context.new(drawcontext);
}
Context.get(c: self ref Context, name: string): list of ref Listnode
{
return sh->c.get(name);
}
Context.set(c: self ref Context, name: string, val: list of ref Listnode)
{
return sh->c.set(name, val);
}
Context.setlocal(c: self ref Context, name: string, val: list of ref Listnode)
{
return sh->c.setlocal(name, val);
}
Context.envlist(c: self ref Context): list of (string, list of ref Listnode)
{
return sh->c.envlist();
}
Context.push(c: self ref Context)
{
return sh->c.push();
}
Context.pop(c: self ref Context)
{
return sh->c.pop();
}
Context.copy(c: self ref Context, copyenv: int): ref Context
{
return sh->c.copy(copyenv);
}
Context.run(c: self ref Context, args: list of ref Listnode, last: int): string
{
return sh->c.run(args, last);
}
Context.fail(c: self ref Context, ename, msg: string)
{
return sh->c.fail(ename, msg);
}
Context.options(c: self ref Context): int
{
return sh->c.options();
}
Context.setoptions(c: self ref Context, flags, on: int): int
{
return sh->c.setoptions(flags, on);
}