ref: 42dfac6916ebbdac65cbec8b3e1a80c3ee41423c
dir: /appl/cmd/sh/sexprs.b/
implement Shellbuiltin; # parse/generate sexprs. include "sys.m"; sys: Sys; include "draw.m"; include "sh.m"; sh: Sh; Listnode, Context: import sh; myself: Shellbuiltin; include "bufio.m"; bufio: Bufio; Iobuf: import bufio; include "sexprs.m"; sexprs: Sexprs; Sexp: import sexprs; # getsexprs cmd # islist val # ${els se} # ${text se} # ${textels se} # ${mktext val} # ${mklist [val...]} # ${mktextlist [val...]} Maxerrs: con 10; initbuiltin(ctxt: ref Context, shmod: Sh): string { sys = load Sys Sys->PATH; sh = shmod; myself = load Shellbuiltin "$self"; if (myself == nil) ctxt.fail("bad module", sys->sprint("sexpr: cannot load self: %r")); bufio = load Bufio Bufio->PATH; if (bufio == nil) ctxt.fail("bad module", sys->sprint("sexpr: cannot load: %s: %r", Bufio->PATH)); sexprs = load Sexprs Sexprs->PATH; if(sexprs == nil) ctxt.fail("bad module", sys->sprint("sexpr: cannot load: %s: %r", Sexprs->PATH)); sexprs->init(); ctxt.addbuiltin("getsexprs", myself); ctxt.addbuiltin("islist", myself); ctxt.addsbuiltin("els", myself); ctxt.addsbuiltin("text", myself); ctxt.addsbuiltin("b64", myself); ctxt.addsbuiltin("textels", myself); ctxt.addsbuiltin("mktext", myself); ctxt.addsbuiltin("mklist", myself); ctxt.addsbuiltin("mktextlist", myself); return nil; } whatis(nil: ref Sh->Context, nil: Sh, nil: string, nil: int): string { return nil; } getself(): Shellbuiltin { return myself; } runbuiltin(c: ref Sh->Context, nil: Sh, cmd: list of ref Sh->Listnode, nil: int): string { case (hd cmd).word { "getsexprs" => return builtin_getsexprs(c, tl cmd); "islist" => return builtin_islist(c, tl cmd); } return nil; } runsbuiltin(c: ref Sh->Context, nil: Sh, cmd: list of ref Sh->Listnode): list of ref Listnode { case (hd cmd).word { "els" => return sbuiltin_els(c, tl cmd); "text" => return sbuiltin_text(c, tl cmd); "b64" => return sbuiltin_b64(c, tl cmd); "textels" => return sbuiltin_textels(c, tl cmd); "mktext" => return sbuiltin_mktext(c, tl cmd); "mklist" => return sbuiltin_mklist(c, tl cmd); "mktextlist" => return sbuiltin_mktextlist(c, tl cmd); } return nil; } builtin_getsexprs(ctxt: ref Context, argv: list of ref Listnode): string { n := len argv; if (n != 1 || !iscmd(hd argv)) builtinusage(ctxt, "getsexprs {cmd}"); cmd := hd argv :: ctxt.get("*"); stdin := bufio->fopen(sys->fildes(0), Sys->OREAD); if (stdin == nil) ctxt.fail("bad input", sys->sprint("getsexprs: cannot open stdin: %r")); status := ""; nerrs := 0; ctxt.push(); for(;;){ { for (;;) { (se, err) := Sexp.read(stdin); if(err != nil){ sys->fprint(sys->fildes(2), "getsexprs: error on read: %s\n", err); if(++nerrs > Maxerrs) raise "fail:too many errors"; continue; } if(se == nil) break; nerrs = 0; ctxt.setlocal("sexp", ref Listnode(nil, se.text()) :: nil); status = setstatus(ctxt, ctxt.run(cmd, 0)); } ctxt.pop(); return status; }exception e{ "fail:*" => ctxt.pop(); if (loopexcept(e) == BREAK) return status; ctxt.push(); } } } builtin_islist(ctxt: ref Context, argv: list of ref Listnode): string { if(argv == nil || tl argv != nil) builtinusage(ctxt, "islist sexp"); w := word(hd argv); if(w != nil && w[0] =='(') return nil; if(parse(ctxt, hd argv).islist()) return nil; return "not a list"; } CONTINUE, BREAK: con iota; loopexcept(ename: string): int { case ename[5:] { "break" => return BREAK; "continue" => return CONTINUE; * => raise ename; } return 0; } iscmd(n: ref Listnode): int { return n.cmd != nil || (n.word != nil && n.word[0] == '{'); } builtinusage(ctxt: ref Context, s: string) { ctxt.fail("usage", "usage: " + s); } setstatus(ctxt: ref Context, val: string): string { ctxt.setlocal("status", ref Listnode(nil, val) :: nil); return val; } sbuiltin_els(ctxt: ref Context, val: list of ref Listnode): list of ref Listnode { if (val == nil || tl val != nil) builtinusage(ctxt, "els sexp"); r, rr: list of ref Listnode; for(els := parse(ctxt, hd val).els(); els != nil; els = tl els) r = ref Listnode(nil, (hd els).text()) :: r; for(; r != nil; r = tl r) rr = hd r :: rr; return rr; } sbuiltin_text(ctxt: ref Context, val: list of ref Listnode): list of ref Listnode { if(val == nil || tl val != nil) builtinusage(ctxt, "text sexp"); return ref Listnode(nil, parse(ctxt, hd val).astext()) :: nil; } sbuiltin_b64(ctxt: ref Context, val: list of ref Listnode): list of ref Listnode { if(val == nil || tl val != nil) builtinusage(ctxt, "b64 sexp"); return ref Listnode(nil, parse(ctxt, hd val).b64text()) :: nil; } sbuiltin_textels(ctxt: ref Context, val: list of ref Listnode): list of ref Listnode { if (val == nil || tl val != nil) builtinusage(ctxt, "textels sexp"); r, rr: list of ref Listnode; for(els := parse(ctxt, hd val).els(); els != nil; els = tl els) r = ref Listnode(nil, (hd els).astext()) :: r; for(; r != nil; r = tl r) rr = hd r :: rr; return rr; } sbuiltin_mktext(ctxt: ref Context, val: list of ref Listnode): list of ref Listnode { if (val == nil || tl val != nil) builtinusage(ctxt, "mktext sexp"); return ref Listnode(nil, (ref Sexp.String(word(hd val), nil)).text()) :: nil; } sbuiltin_mklist(nil: ref Context, val: list of ref Listnode): list of ref Listnode { if(val == nil) return ref Listnode(nil, "()") :: nil; s := "(" + word(hd val); for(val = tl val; val != nil; val = tl val) s += " " + word(hd val); s[len s] = ')'; return ref Listnode(nil, s) :: nil; } sbuiltin_mktextlist(nil: ref Context, val: list of ref Listnode): list of ref Listnode { if(val == nil) return ref Listnode(nil, "()") :: nil; s := "(" + (ref Sexp.String(word(hd val), nil)).text(); for(val = tl val; val != nil; val = tl val) s += " " + (ref Sexp.String(word(hd val), nil)).text(); s[len s] = ')'; return ref Listnode(nil, s) :: nil; } parse(ctxt: ref Context, val: ref Listnode): ref Sexp { (se, rest, err) := Sexp.parse(word(val)); if(rest != nil){ for(i := 0; i < len rest; i++) if(rest[i] != ' ' && rest[i] != '\t' && rest[i] != '\n') ctxt.fail("bad sexp", sys->sprint("extra text found at end of s-expression %#q", word(val))); } if(err != nil) ctxt.fail("bad sexp", err); return se; } word(n: ref Listnode): string { if (n.word != nil) return n.word; if (n.cmd != nil) n.word = sh->cmd2string(n.cmd); return n.word; }