ref: a411870ee4640241e3c494367d922847da84f972
dir: /appl/cmd/sh/arg.b/
implement Shellbuiltin; include "sys.m"; sys: Sys; include "draw.m"; include "sh.m"; sh: Sh; Listnode, Context: import sh; myself: Shellbuiltin; initbuiltin(ctxt: ref Context, shmod: Sh): string { sys = load Sys Sys->PATH; sh = shmod; myself = load Shellbuiltin "$self"; if (myself == nil) ctxt.fail("bad module", sys->sprint("arg: cannot load self: %r")); ctxt.addbuiltin("arg", myself); return nil; } whatis(nil: ref Sh->Context, nil: Sh, nil: string, nil: int): string { return nil; } getself(): Shellbuiltin { return myself; } runbuiltin(ctxt: ref Context, nil: Sh, argv: list of ref Listnode, last: int): string { case (hd argv).word { "arg" => return builtin_arg(ctxt, argv, last); } return nil; } runsbuiltin(nil: ref Sh->Context, nil: Sh, nil: list of ref Listnode): list of ref Listnode { return nil; } argusage(ctxt: ref Context) { ctxt.fail("usage", "usage: arg [opts {command}]... - args"); } builtin_arg(ctxt: ref Context, argv: list of ref Listnode, nil: int): string { for (args := tl argv; args != nil; args = tl tl args) { if ((hd args).word == "-") break; if ((hd args).cmd != nil && (hd args).word == nil) argusage(ctxt); if (tl args == nil) argusage(ctxt); if ((hd tl args).cmd == nil) argusage(ctxt); } if (args == nil) args = ctxt.get("*"); else args = tl args; laststatus := ""; ctxt.push(); { arg := Arg.init(args); while ((opt := arg.opt()) != 0) { for (argt := tl argv; argt != nil && (hd argt).word != "-"; argt = tl tl argt) { w := (hd argt).word; argcount := 0; for (e := len w - 1; e >= 0; e--) { if (w[e] != '+') break; argcount++; } w = w[0:e+1]; if (w == nil) continue; for (i := 0; i < len w; i++) if (w[i] == opt || w[i] == '*') break; if (i < len w) { optstr := ""; optstr[0] = opt; ctxt.setlocal("opt", ref Listnode(nil, optstr) :: nil); args = arg.arg(argcount); if (argcount > 0 && args == nil) ctxt.fail("usage", sys->sprint("option -%c requires %d arguments", opt, argcount)); ctxt.setlocal("arg", args); laststatus = ctxt.run(hd tl argt :: nil, 0); break; } } if (argt == nil || (hd argt).word == "-") ctxt.fail("usage", sys->sprint("unknown option -%c", opt)); } ctxt.pop(); ctxt.set("args", arg.args); # XXX backward compatibility - should go ctxt.set("*", arg.args); return laststatus; } exception e{ "fail:*" => ctxt.pop(); if (e[5:] == "break") return laststatus; raise e; } } Arg: adt { args: list of ref Listnode; curropt: string; init: fn(argv: list of ref Listnode): ref Arg; arg: fn(ctxt: self ref Arg, n: int): list of ref Listnode; opt: fn(ctxt: self ref Arg): int; }; Arg.init(argv: list of ref Listnode): ref Arg { return ref Arg(argv, nil); } # get next n option arguments (nil list if not enough arguments found) Arg.arg(ctxt: self ref Arg, n: int): list of ref Listnode { if (n == 0) return nil; args: list of ref Listnode; while (--n >= 0) { if (ctxt.curropt != nil) { args = ref Listnode(nil, ctxt.curropt) :: args; ctxt.curropt = nil; } else if (ctxt.args == nil) return nil; else { args = hd ctxt.args :: args; ctxt.args = tl ctxt.args; } } r: list of ref Listnode; for (; args != nil; args = tl args) r = hd args :: r; return r; } # get next option letter # return 0 at end of options Arg.opt(ctxt: self ref Arg): int { if (ctxt.curropt != "") { opt := ctxt.curropt[0]; ctxt.curropt = ctxt.curropt[1:]; return opt; } if (ctxt.args == nil) return 0; nextarg := (hd ctxt.args).word; if (len nextarg < 2 || nextarg[0] != '-') return 0; if (nextarg == "--") { ctxt.args = tl ctxt.args; return 0; } opt := nextarg[1]; if (len nextarg > 2) ctxt.curropt = nextarg[2:]; ctxt.args = tl ctxt.args; return opt; }