20060303a

1 files changed, 212 insertions, 0 deletions

diff --git a/appl/cmd/sh/string.b b/appl/cmd/sh/string.b
new file mode 100644
index 00000000..b6d079e4
--- /dev/null
+++ b/appl/cmd/sh/string.b
@@ -0,0 +1,212 @@
+implement Shellbuiltin;
+
+include "sys.m";
+	sys: Sys;
+include "draw.m";
+include "sh.m";
+	sh: Sh;
+	Listnode, Context: import sh;
+	myself: Shellbuiltin;
+include "string.m";
+	str: String;
+
+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("string: cannot load self: %r"));
+	str = load String String->PATH;
+	if (str == nil)
+		ctxt.fail("bad module",
+			sys->sprint("string: cannot load %s: %r", String->PATH));
+	ctxt.addbuiltin("prefix", myself);
+	ctxt.addbuiltin("in", myself);
+	names := array[] of {
+	"splitl", "splitr", "drop", "take", "splitstrl", "splitstrr",
+	"tolower", "toupper", "len", "alen", "slice", "fields",
+	"padl", "padr",
+	};
+	for (i := 0; i < len names; i++)
+		ctxt.addsbuiltin(names[i], 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, nil: int): string
+{
+	case (hd argv).word {
+	"prefix" =>
+		(a, b) := earg2("prefix", ctxt, argv);
+		if (!str->prefix(a, b))
+			return "false";
+	"in" =>
+		(a, b) := earg2("in", ctxt, argv);
+		if (a == nil || !str->in(a[0], b))
+			return "false";
+	}
+	return nil;
+}
+
+runsbuiltin(ctxt: ref Context, nil: Sh,
+			argv: list of ref Listnode): list of ref Listnode
+{
+	name := (hd argv).word;
+	case name {
+	"splitl" =>
+		(a, b) := earg2("splitl", ctxt, argv);
+		return mk2(str->splitl(a, b));
+	"splitr" =>
+		(a, b) := earg2("splitr", ctxt, argv);
+		return mk2(str->splitr(a, b));
+	"drop" =>
+		(a, b) := earg2("drop", ctxt, argv);
+		return mk1(str->drop(a, b));
+	"take" =>
+		(a, b) := earg2("take", ctxt, argv);
+		return mk1(str->take(a, b));
+	"splitstrl" =>
+		(a, b) := earg2("splitstrl", ctxt, argv);
+		return mk2(str->splitstrl(a, b));
+	"splitstrr" =>
+		(a, b) := earg2("splitstrr", ctxt, argv);
+		return mk2(str->splitstrr(a, b));
+	"tolower" =>
+		return mk1(str->tolower(earg1("tolower", ctxt, argv)));
+	"toupper" =>
+		return mk1(str->toupper(earg1("tolower", ctxt, argv)));
+	"len" =>
+		return mk1(string len earg1("len", ctxt, argv));
+	"alen" =>
+		return mk1(string len array of byte earg1("alen", ctxt, argv));
+	"slice" =>
+		return sbuiltin_slice(ctxt, argv);
+	"fields" =>
+		return sbuiltin_fields(ctxt, argv);
+	"padl" =>
+		return sbuiltin_pad(ctxt, argv, -1);
+	"padr" =>
+		return sbuiltin_pad(ctxt, argv, 1);
+	}
+	return nil;
+}
+
+sbuiltin_pad(ctxt: ref Context, argv: list of ref Listnode, dir: int): list of ref Listnode
+{
+	if (tl argv == nil || !isnum((hd tl argv).word))
+		ctxt.fail("usage", "usage: " + (hd argv).word + " n [arg...]");
+
+	argv = tl argv;
+	n := int (hd argv).word * dir;
+	s := "";
+	for (argv = tl argv; argv != nil; argv = tl argv) {
+		s += word(hd argv);
+		if (tl argv != nil)
+			s[len s] = ' ';
+	}
+	if (n != 0)
+		s =  sys->sprint("%*s", n, s);
+	return ref Listnode(nil, s) :: nil;
+}
+
+sbuiltin_fields(ctxt: ref Context, argv: list of ref Listnode): list of ref Listnode
+{
+	argv = tl argv;
+	if (len argv != 2)
+		ctxt.fail("usage", "usage: fields cl s");
+	cl := word(hd argv);
+	s := word(hd tl argv);
+
+	r: list of string;
+
+	n := 0;
+	for (i := 0; i < len s; i++) {
+		if (str->in(s[i], cl)) {
+			r = s[n:i] :: r;
+			n = i + 1;
+		}
+	}
+	r = s[n:i] :: r;
+	rl: list of ref Listnode;
+	for (; r != nil; r = tl r)
+		rl = ref Listnode(nil, hd r) :: rl;
+	return rl;
+}
+
+
+sbuiltin_slice(ctxt: ref Context, argv: list of ref Listnode): list of ref Listnode
+{
+	argv = tl argv;
+	if (len argv != 3 || !isnum((hd argv).word) ||
+			(hd tl argv).word != "end" && !isnum((hd tl argv).word))
+		ctxt.fail("usage", "usage: slice start end arg");
+	n1 := int (hd argv).word;
+	n2: int;
+	s := word(hd tl tl argv);
+	r := "";
+	if ((hd tl argv).word == "end")
+		n2 = len s;
+	else
+		n2 = int (hd tl argv).word;
+	if (n2 > len s)
+		n2 = len s;
+	if (n1 > len s)
+		n1 = len s;
+	if (n2 > n1)
+		r = s[n1:n2];
+	return mk1(r);
+}
+
+earg2(cmd: string, ctxt: ref Context, argv: list of ref Listnode): (string, string)
+{
+	argv = tl argv;
+	if (len argv != 2)
+		ctxt.fail("usage", "usage: " + cmd + " arg1 arg2");
+	return (word(hd argv), word(hd tl argv));
+}
+
+earg1(cmd: string, ctxt: ref Context, argv: list of ref Listnode): string
+{
+	if (len argv != 2)
+		ctxt.fail("usage", "usage: " + cmd + " arg");
+	return word(hd tl argv);
+}
+
+mk2(x: (string, string)): list of ref Listnode
+{
+	(a, b) := x;
+	return ref Listnode(nil, a) :: ref Listnode(nil, b) :: nil;
+}
+
+mk1(x: string): list of ref Listnode
+{
+	return ref Listnode(nil, x) :: nil;
+}
+
+isnum(s: string): int
+{
+	for (i := 0; i < len s; i++)
+		if (s[i] > '9' || s[i] < '0')
+			return 0;
+	return 1;
+}
+
+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;
+}