Add mksh from CVS 2010/08/24 as system/core/mksh module

Both shells (ash from system/core/sh, and mksh) are built by
default but only the one where $(TARGET_SHELL) is set to is
actually installed (the shell and the mkshrc configuration
file are tagged shell_mksh for this to work).

Signed-off-by: Thorsten Glaser <tg@mirbsd.org>
diff --git a/mksh/src/tree.c b/mksh/src/tree.c
new file mode 100644
index 0000000..aa861db
--- /dev/null
+++ b/mksh/src/tree.c
@@ -0,0 +1,716 @@
+/*	$OpenBSD: tree.c,v 1.19 2008/08/11 21:50:35 jaredy Exp $	*/
+
+/*-
+ * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ *	Thorsten Glaser <tg@mirbsd.org>
+ *
+ * Provided that these terms and disclaimer and all copyright notices
+ * are retained or reproduced in an accompanying document, permission
+ * is granted to deal in this work without restriction, including un-
+ * limited rights to use, publicly perform, distribute, sell, modify,
+ * merge, give away, or sublicence.
+ *
+ * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
+ * the utmost extent permitted by applicable law, neither express nor
+ * implied; without malicious intent or gross negligence. In no event
+ * may a licensor, author or contributor be held liable for indirect,
+ * direct, other damage, loss, or other issues arising in any way out
+ * of dealing in the work, even if advised of the possibility of such
+ * damage or existence of a defect, except proven that it results out
+ * of said person's immediate fault when using the work as intended.
+ */
+
+#include "sh.h"
+
+__RCSID("$MirOS: src/bin/mksh/tree.c,v 1.30 2010/02/25 20:18:19 tg Exp $");
+
+#define INDENT	4
+
+#define tputc(c, shf) shf_putchar(c, shf);
+static void ptree(struct op *, int, struct shf *);
+static void pioact(struct shf *, int, struct ioword *);
+static void tputC(int, struct shf *);
+static void tputS(char *, struct shf *);
+static void vfptreef(struct shf *, int, const char *, va_list);
+static struct ioword **iocopy(struct ioword **, Area *);
+static void iofree(struct ioword **, Area *);
+
+/*
+ * print a command tree
+ */
+static void
+ptree(struct op *t, int indent, struct shf *shf)
+{
+	const char **w;
+	struct ioword **ioact;
+	struct op *t1;
+
+ Chain:
+	if (t == NULL)
+		return;
+	switch (t->type) {
+	case TCOM:
+		if (t->vars)
+			for (w = (const char **)t->vars; *w != NULL; )
+				fptreef(shf, indent, "%S ", *w++);
+		else
+			shf_puts("#no-vars# ", shf);
+		if (t->args)
+			for (w = t->args; *w != NULL; )
+				fptreef(shf, indent, "%S ", *w++);
+		else
+			shf_puts("#no-args# ", shf);
+		break;
+	case TEXEC:
+		t = t->left;
+		goto Chain;
+	case TPAREN:
+		fptreef(shf, indent + 2, "( %T) ", t->left);
+		break;
+	case TPIPE:
+		fptreef(shf, indent, "%T| ", t->left);
+		t = t->right;
+		goto Chain;
+	case TLIST:
+		fptreef(shf, indent, "%T%;", t->left);
+		t = t->right;
+		goto Chain;
+	case TOR:
+	case TAND:
+		fptreef(shf, indent, "%T%s %T",
+		    t->left, (t->type==TOR) ? "||" : "&&", t->right);
+		break;
+	case TBANG:
+		shf_puts("! ", shf);
+		t = t->right;
+		goto Chain;
+	case TDBRACKET: {
+		int i;
+
+		shf_puts("[[", shf);
+		for (i = 0; t->args[i]; i++)
+			fptreef(shf, indent, " %S", t->args[i]);
+		shf_puts(" ]] ", shf);
+		break;
+	}
+	case TSELECT:
+		fptreef(shf, indent, "select %s ", t->str);
+		/* FALLTHROUGH */
+	case TFOR:
+		if (t->type == TFOR)
+			fptreef(shf, indent, "for %s ", t->str);
+		if (t->vars != NULL) {
+			shf_puts("in ", shf);
+			for (w = (const char **)t->vars; *w; )
+				fptreef(shf, indent, "%S ", *w++);
+			fptreef(shf, indent, "%;");
+		}
+		fptreef(shf, indent + INDENT, "do%N%T", t->left);
+		fptreef(shf, indent, "%;done ");
+		break;
+	case TCASE:
+		fptreef(shf, indent, "case %S in", t->str);
+		for (t1 = t->left; t1 != NULL; t1 = t1->right) {
+			fptreef(shf, indent, "%N(");
+			for (w = (const char **)t1->vars; *w != NULL; w++)
+				fptreef(shf, indent, "%S%c", *w,
+				    (w[1] != NULL) ? '|' : ')');
+			fptreef(shf, indent + INDENT, "%;%T%N;;", t1->left);
+		}
+		fptreef(shf, indent, "%Nesac ");
+		break;
+	case TIF:
+	case TELIF:
+		/* 3 == strlen("if ") */
+		fptreef(shf, indent + 3, "if %T", t->left);
+		for (;;) {
+			t = t->right;
+			if (t->left != NULL) {
+				fptreef(shf, indent, "%;");
+				fptreef(shf, indent + INDENT, "then%N%T",
+				    t->left);
+			}
+			if (t->right == NULL || t->right->type != TELIF)
+				break;
+			t = t->right;
+			fptreef(shf, indent, "%;");
+			/* 5 == strlen("elif ") */
+			fptreef(shf, indent + 5, "elif %T", t->left);
+		}
+		if (t->right != NULL) {
+			fptreef(shf, indent, "%;");
+			fptreef(shf, indent + INDENT, "else%;%T", t->right);
+		}
+		fptreef(shf, indent, "%;fi ");
+		break;
+	case TWHILE:
+	case TUNTIL:
+		/* 6 == strlen("while"/"until") */
+		fptreef(shf, indent + 6, "%s %T",
+		    (t->type==TWHILE) ? "while" : "until",
+		    t->left);
+		fptreef(shf, indent, "%;do");
+		fptreef(shf, indent + INDENT, "%;%T", t->right);
+		fptreef(shf, indent, "%;done ");
+		break;
+	case TBRACE:
+		fptreef(shf, indent + INDENT, "{%;%T", t->left);
+		fptreef(shf, indent, "%;} ");
+		break;
+	case TCOPROC:
+		fptreef(shf, indent, "%T|& ", t->left);
+		break;
+	case TASYNC:
+		fptreef(shf, indent, "%T& ", t->left);
+		break;
+	case TFUNCT:
+		fptreef(shf, indent,
+		    t->u.ksh_func ? "function %s %T" : "%s() %T",
+		    t->str, t->left);
+		break;
+	case TTIME:
+		fptreef(shf, indent, "time %T", t->left);
+		break;
+	default:
+		shf_puts("<botch>", shf);
+		break;
+	}
+	if ((ioact = t->ioact) != NULL) {
+		int	need_nl = 0;
+
+		while (*ioact != NULL)
+			pioact(shf, indent, *ioact++);
+		/* Print here documents after everything else... */
+		for (ioact = t->ioact; *ioact != NULL; ) {
+			struct ioword *iop = *ioact++;
+
+			/* heredoc is 0 when tracing (set -x) */
+			if ((iop->flag & IOTYPE) == IOHERE && iop->heredoc &&
+			    /* iop->delim[1] == '<' means here string */
+			    (!iop->delim || iop->delim[1] != '<')) {
+				tputc('\n', shf);
+				shf_puts(iop->heredoc, shf);
+				fptreef(shf, indent, "%s",
+				    evalstr(iop->delim, 0));
+				need_nl = 1;
+			}
+		}
+		/* Last delimiter must be followed by a newline (this often
+		 * leads to an extra blank line, but its not worth worrying
+		 * about)
+		 */
+		if (need_nl)
+			tputc('\n', shf);
+	}
+}
+
+static void
+pioact(struct shf *shf, int indent, struct ioword *iop)
+{
+	int flag = iop->flag;
+	int type = flag & IOTYPE;
+	int expected;
+
+	expected = (type == IOREAD || type == IORDWR || type == IOHERE) ? 0 :
+	    (type == IOCAT || type == IOWRITE) ? 1 :
+	    (type == IODUP && (iop->unit == !(flag & IORDUP))) ? iop->unit :
+	    iop->unit + 1;
+	if (iop->unit != expected)
+		shf_fprintf(shf, "%d", iop->unit);
+
+	switch (type) {
+	case IOREAD:
+		shf_puts("< ", shf);
+		break;
+	case IOHERE:
+		shf_puts(flag & IOSKIP ? "<<-" : "<<", shf);
+		break;
+	case IOCAT:
+		shf_puts(">> ", shf);
+		break;
+	case IOWRITE:
+		shf_puts(flag & IOCLOB ? ">| " : "> ", shf);
+		break;
+	case IORDWR:
+		shf_puts("<> ", shf);
+		break;
+	case IODUP:
+		shf_puts(flag & IORDUP ? "<&" : ">&", shf);
+		break;
+	}
+	/* name/delim are 0 when printing syntax errors */
+	if (type == IOHERE) {
+		if (iop->delim)
+			fptreef(shf, indent, "%s%S ",
+			    /* here string */ iop->delim[1] == '<' ? "" : " ",
+			    iop->delim);
+		else
+			tputc(' ', shf);
+	} else if (iop->name)
+		fptreef(shf, indent, (iop->flag & IONAMEXP) ? "%s " : "%S ",
+		    iop->name);
+}
+
+
+/*
+ * variants of fputc, fputs for ptreef and snptreef
+ */
+static void
+tputC(int c, struct shf *shf)
+{
+	if ((c&0x60) == 0) {		/* C0|C1 */
+		tputc((c&0x80) ? '$' : '^', shf);
+		tputc(((c&0x7F)|0x40), shf);
+	} else if ((c&0x7F) == 0x7F) {	/* DEL */
+		tputc((c&0x80) ? '$' : '^', shf);
+		tputc('?', shf);
+	} else
+		tputc(c, shf);
+}
+
+static void
+tputS(char *wp, struct shf *shf)
+{
+	int c, quotelevel = 0;
+
+	/* problems:
+	 *	`...` -> $(...)
+	 *	'foo' -> "foo"
+	 * could change encoding to:
+	 *	OQUOTE ["'] ... CQUOTE ["']
+	 *	COMSUB [(`] ...\0	(handle $ ` \ and maybe " in `...` case)
+	 */
+	while (1)
+		switch (*wp++) {
+		case EOS:
+			return;
+		case ADELIM:
+		case CHAR:
+			tputC(*wp++, shf);
+			break;
+		case QCHAR:
+			c = *wp++;
+			if (!quotelevel || (c == '"' || c == '`' || c == '$'))
+				tputc('\\', shf);
+			tputC(c, shf);
+			break;
+		case COMSUB:
+			shf_puts("$(", shf);
+			while (*wp != 0)
+				tputC(*wp++, shf);
+			tputc(')', shf);
+			wp++;
+			break;
+		case EXPRSUB:
+			shf_puts("$((", shf);
+			while (*wp != 0)
+				tputC(*wp++, shf);
+			shf_puts("))", shf);
+			wp++;
+			break;
+		case OQUOTE:
+			quotelevel++;
+			tputc('"', shf);
+			break;
+		case CQUOTE:
+			if (quotelevel)
+				quotelevel--;
+			tputc('"', shf);
+			break;
+		case OSUBST:
+			tputc('$', shf);
+			if (*wp++ == '{')
+				tputc('{', shf);
+			while ((c = *wp++) != 0)
+				tputC(c, shf);
+			break;
+		case CSUBST:
+			if (*wp++ == '}')
+				tputc('}', shf);
+			break;
+		case OPAT:
+			tputc(*wp++, shf);
+			tputc('(', shf);
+			break;
+		case SPAT:
+			tputc('|', shf);
+			break;
+		case CPAT:
+			tputc(')', shf);
+			break;
+		}
+}
+
+/*
+ * this is the _only_ way to reliably handle
+ * variable args with an ANSI compiler
+ */
+/* VARARGS */
+int
+fptreef(struct shf *shf, int indent, const char *fmt, ...)
+{
+	va_list va;
+
+	va_start(va, fmt);
+
+	vfptreef(shf, indent, fmt, va);
+	va_end(va);
+	return (0);
+}
+
+/* VARARGS */
+char *
+snptreef(char *s, int n, const char *fmt, ...)
+{
+	va_list va;
+	struct shf shf;
+
+	shf_sopen(s, n, SHF_WR | (s ? 0 : SHF_DYNAMIC), &shf);
+
+	va_start(va, fmt);
+	vfptreef(&shf, 0, fmt, va);
+	va_end(va);
+
+	return (shf_sclose(&shf)); /* null terminates */
+}
+
+static void
+vfptreef(struct shf *shf, int indent, const char *fmt, va_list va)
+{
+	int c;
+
+	while ((c = *fmt++)) {
+		if (c == '%') {
+			switch ((c = *fmt++)) {
+			case 'c':
+				tputc(va_arg(va, int), shf);
+				break;
+			case 's':
+				shf_puts(va_arg(va, char *), shf);
+				break;
+			case 'S':	/* word */
+				tputS(va_arg(va, char *), shf);
+				break;
+			case 'd':	/* decimal */
+				shf_fprintf(shf, "%d", va_arg(va, int));
+				break;
+			case 'u':	/* decimal */
+				shf_fprintf(shf, "%u", va_arg(va, unsigned int));
+				break;
+			case 'T':	/* format tree */
+				ptree(va_arg(va, struct op *), indent, shf);
+				break;
+			case ';':	/* newline or ; */
+			case 'N':	/* newline or space */
+				if (shf->flags & SHF_STRING) {
+					if (c == ';')
+						tputc(';', shf);
+					tputc(' ', shf);
+				} else {
+					int i;
+
+					tputc('\n', shf);
+					for (i = indent; i >= 8; i -= 8)
+						tputc('\t', shf);
+					for (; i > 0; --i)
+						tputc(' ', shf);
+				}
+				break;
+			case 'R':
+				pioact(shf, indent, va_arg(va, struct ioword *));
+				break;
+			default:
+				tputc(c, shf);
+				break;
+			}
+		} else
+			tputc(c, shf);
+	}
+}
+
+/*
+ * copy tree (for function definition)
+ */
+struct op *
+tcopy(struct op *t, Area *ap)
+{
+	struct op *r;
+	const char **tw;
+	char **rw;
+
+	if (t == NULL)
+		return (NULL);
+
+	r = alloc(sizeof(struct op), ap);
+
+	r->type = t->type;
+	r->u.evalflags = t->u.evalflags;
+
+	if (t->type == TCASE)
+		r->str = wdcopy(t->str, ap);
+	else
+		strdupx(r->str, t->str, ap);
+
+	if (t->vars == NULL)
+		r->vars = NULL;
+	else {
+		for (tw = (const char **)t->vars; *tw++ != NULL; )
+			;
+		rw = r->vars = alloc((tw - (const char **)t->vars + 1) *
+		    sizeof(*tw), ap);
+		for (tw = (const char **)t->vars; *tw != NULL; )
+			*rw++ = wdcopy(*tw++, ap);
+		*rw = NULL;
+	}
+
+	if (t->args == NULL)
+		r->args = NULL;
+	else {
+		for (tw = t->args; *tw++ != NULL; )
+			;
+		r->args = (const char **)(rw = alloc((tw - t->args + 1) *
+		    sizeof(*tw), ap));
+		for (tw = t->args; *tw != NULL; )
+			*rw++ = wdcopy(*tw++, ap);
+		*rw = NULL;
+	}
+
+	r->ioact = (t->ioact == NULL) ? NULL : iocopy(t->ioact, ap);
+
+	r->left = tcopy(t->left, ap);
+	r->right = tcopy(t->right, ap);
+	r->lineno = t->lineno;
+
+	return (r);
+}
+
+char *
+wdcopy(const char *wp, Area *ap)
+{
+	size_t len = wdscan(wp, EOS) - wp;
+	return (memcpy(alloc(len, ap), wp, len));
+}
+
+/* return the position of prefix c in wp plus 1 */
+const char *
+wdscan(const char *wp, int c)
+{
+	int nest = 0;
+
+	while (1)
+		switch (*wp++) {
+		case EOS:
+			return (wp);
+		case ADELIM:
+			if (c == ADELIM)
+				return (wp + 1);
+			/* FALLTHROUGH */
+		case CHAR:
+		case QCHAR:
+			wp++;
+			break;
+		case COMSUB:
+		case EXPRSUB:
+			while (*wp++ != 0)
+				;
+			break;
+		case OQUOTE:
+		case CQUOTE:
+			break;
+		case OSUBST:
+			nest++;
+			while (*wp++ != '\0')
+				;
+			break;
+		case CSUBST:
+			wp++;
+			if (c == CSUBST && nest == 0)
+				return (wp);
+			nest--;
+			break;
+		case OPAT:
+			nest++;
+			wp++;
+			break;
+		case SPAT:
+		case CPAT:
+			if (c == wp[-1] && nest == 0)
+				return (wp);
+			if (wp[-1] == CPAT)
+				nest--;
+			break;
+		default:
+			internal_warningf(
+			    "wdscan: unknown char 0x%x (carrying on)",
+			    wp[-1]);
+		}
+}
+
+/* return a copy of wp without any of the mark up characters and
+ * with quote characters (" ' \) stripped.
+ * (string is allocated from ATEMP)
+ */
+char *
+wdstrip(const char *wp, bool keepq, bool make_magic)
+{
+	struct shf shf;
+	int c;
+
+	shf_sopen(NULL, 32, SHF_WR | SHF_DYNAMIC, &shf);
+
+	/* problems:
+	 *	`...` -> $(...)
+	 *	x${foo:-"hi"} -> x${foo:-hi}
+	 *	x${foo:-'hi'} -> x${foo:-hi} unless keepq
+	 */
+	while (1)
+		switch (*wp++) {
+		case EOS:
+			return (shf_sclose(&shf)); /* null terminates */
+		case ADELIM:
+		case CHAR:
+			c = *wp++;
+			if (make_magic && (ISMAGIC(c) || c == '[' || c == NOT ||
+			    c == '-' || c == ']' || c == '*' || c == '?'))
+				shf_putchar(MAGIC, &shf);
+			shf_putchar(c, &shf);
+			break;
+		case QCHAR:
+			c = *wp++;
+			if (keepq && (c == '"' || c == '`' || c == '$' || c == '\\'))
+				shf_putchar('\\', &shf);
+			shf_putchar(c, &shf);
+			break;
+		case COMSUB:
+			shf_puts("$(", &shf);
+			while (*wp != 0)
+				shf_putchar(*wp++, &shf);
+			shf_putchar(')', &shf);
+			break;
+		case EXPRSUB:
+			shf_puts("$((", &shf);
+			while (*wp != 0)
+				shf_putchar(*wp++, &shf);
+			shf_puts("))", &shf);
+			break;
+		case OQUOTE:
+			break;
+		case CQUOTE:
+			break;
+		case OSUBST:
+			shf_putchar('$', &shf);
+			if (*wp++ == '{')
+			    shf_putchar('{', &shf);
+			while ((c = *wp++) != 0)
+				shf_putchar(c, &shf);
+			break;
+		case CSUBST:
+			if (*wp++ == '}')
+				shf_putchar('}', &shf);
+			break;
+		case OPAT:
+			if (make_magic) {
+				shf_putchar(MAGIC, &shf);
+				shf_putchar(*wp++ | 0x80, &shf);
+			} else {
+				shf_putchar(*wp++, &shf);
+				shf_putchar('(', &shf);
+			}
+			break;
+		case SPAT:
+			if (make_magic)
+				shf_putchar(MAGIC, &shf);
+			shf_putchar('|', &shf);
+			break;
+		case CPAT:
+			if (make_magic)
+				shf_putchar(MAGIC, &shf);
+			shf_putchar(')', &shf);
+			break;
+		}
+}
+
+static struct ioword **
+iocopy(struct ioword **iow, Area *ap)
+{
+	struct ioword **ior;
+	int i;
+
+	for (ior = iow; *ior++ != NULL; )
+		;
+	ior = alloc((ior - iow + 1) * sizeof(struct ioword *), ap);
+
+	for (i = 0; iow[i] != NULL; i++) {
+		struct ioword *p, *q;
+
+		p = iow[i];
+		q = alloc(sizeof(struct ioword), ap);
+		ior[i] = q;
+		*q = *p;
+		if (p->name != NULL)
+			q->name = wdcopy(p->name, ap);
+		if (p->delim != NULL)
+			q->delim = wdcopy(p->delim, ap);
+		if (p->heredoc != NULL)
+			strdupx(q->heredoc, p->heredoc, ap);
+	}
+	ior[i] = NULL;
+
+	return (ior);
+}
+
+/*
+ * free tree (for function definition)
+ */
+void
+tfree(struct op *t, Area *ap)
+{
+	char **w;
+
+	if (t == NULL)
+		return;
+
+	if (t->str != NULL)
+		afree(t->str, ap);
+
+	if (t->vars != NULL) {
+		for (w = t->vars; *w != NULL; w++)
+			afree(*w, ap);
+		afree(t->vars, ap);
+	}
+
+	if (t->args != NULL) {
+		union mksh_ccphack cw;
+		/* XXX we assume the caller is right */
+		cw.ro = t->args;
+		for (w = cw.rw; *w != NULL; w++)
+			afree(*w, ap);
+		afree(t->args, ap);
+	}
+
+	if (t->ioact != NULL)
+		iofree(t->ioact, ap);
+
+	tfree(t->left, ap);
+	tfree(t->right, ap);
+
+	afree(t, ap);
+}
+
+static void
+iofree(struct ioword **iow, Area *ap)
+{
+	struct ioword **iop;
+	struct ioword *p;
+
+	for (iop = iow; (p = *iop++) != NULL; ) {
+		if (p->name != NULL)
+			afree(p->name, ap);
+		if (p->delim != NULL)
+			afree(p->delim, ap);
+		if (p->heredoc != NULL)
+			afree(p->heredoc, ap);
+		afree(p, ap);
+	}
+	afree(iow, ap);
+}