diff options
Diffstat (limited to 'appl/cmd/sh/sexprs.b')
| -rw-r--r-- | appl/cmd/sh/sexprs.b | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/appl/cmd/sh/sexprs.b b/appl/cmd/sh/sexprs.b new file mode 100644 index 00000000..1908078a --- /dev/null +++ b/appl/cmd/sh/sexprs.b @@ -0,0 +1,271 @@ +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; +} |