add a sleep builtin that can deal with fractions too

funcs.c

@@ -26,7 +26,19 @@
 
 #include "sh.h"
 
-__RCSID("$MirOS: src/bin/mksh/funcs.c,v 1.168 2011/01/30 01:35:58 tg Exp $");
+#if HAVE_SELECT
+#if HAVE_SYS_BSDTYPES_H
+#include <sys/bsdtypes.h>
+#endif
+#if HAVE_SYS_SELECT_H
+#include <sys/select.h>
+#endif
+#if HAVE_BSTRING_H
+#include <bstring.h>
+#endif
+#endif
+
+__RCSID("$MirOS: src/bin/mksh/funcs.c,v 1.169 2011/02/11 00:41:34 tg Exp $");
 
 #if HAVE_KILLPG
 /*
@@ -112,6 +124,9 @@ const struct builtin mkshbuiltins[] = {
 #endif
 	{"realpath", c_realpath},
 	{"rename", c_rename},
+#if HAVE_SELECT
+	{"sleep", c_sleep},
+#endif
 	{NULL, (int (*)(const char **))NULL}
 };
 
@@ -3647,3 +3662,43 @@ c_cat(const char **wp)
 	free(buf);
 	return (rv);
 }
+
+#if HAVE_SELECT
+int
+c_sleep(const char **wp)
+{
+	struct timeval tv;
+	int rv = 1;
+
+	/* skip argv[0] */
+	++wp;
+	if (wp[0] && !strcmp(wp[0], "--"))
+		/* skip "--" (options separator) */
+		++wp;
+
+	if (!wp[0] || wp[1])
+		bi_errorf(T_synerr);
+	else if (parse_usec(wp[0], &tv))
+		bi_errorf("%s: %s '%s'", T_synerr, strerror(errno), wp[0]);
+	else {
+#ifndef MKSH_NOPROSPECTOFWORK
+		sigset_t omask;
+
+		/* block SIGCHLD from interrupting us, though */
+		sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+#endif
+		if (select(0, NULL, NULL, NULL, &tv) == 0 || errno == EINTR)
+			/*
+			 * strictly speaking only for SIGALRM, but the
+			 * execution may be interrupted by other signals
+			 */
+			rv = 0;
+		else
+			bi_errorf("%s: %s", T_select, strerror(errno));
+#ifndef MKSH_NOPROSPECTOFWORK
+		sigprocmask(SIG_BLOCK, &omask, NULL);
+#endif
+	}
+	return (rv);
+}
+#endif

mksh.1

@@ -1,4 +1,4 @@
-.\" $MirOS: src/bin/mksh/mksh.1,v 1.248 2011/02/09 13:08:18 tg Exp $
+.\" $MirOS: src/bin/mksh/mksh.1,v 1.249 2011/02/11 00:41:35 tg Exp $
 .\" $OpenBSD: ksh.1,v 1.138 2010/09/20 07:41:17 jmc Exp $
 .\"-
 .\" Copyright © 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
@@ -72,7 +72,7 @@
 .\" with -mandoc, it might implement .Mx itself, but we want to
 .\" use our own definition. And .Dd must come *first*, always.
 .\"
-.Dd $Mdocdate: February 9 2011 $
+.Dd $Mdocdate: February 11 2011 $
 .\"
 .\" Check which macro package we use
 .\"
@@ -2805,7 +2805,7 @@ regular commands
 .Ic \&[ , chdir , bind , cat ,
 .Ic echo , let , mknod , print ,
 .Ic printf , pwd , realpath , rename ,
-.Ic test , ulimit , whence
+.Ic sleep , test , ulimit , whence
 .Pp
 In the future, the additional
 .Nm
@@ -4047,6 +4047,11 @@ etc.
 .Ar number
 defaults to 1.
 .Pp
+.It Ic sleep Ar seconds
+Suspends execution for a minimum of the
+.Ar seconds
+specified as positive decimal value with an optional fractional part.
+Signal delivery may continue execution earlier.
 .It Ic source Ar file Op Ar arg ...
 Like
 .Ic \&. Po Do dot Dc Pc ,

sh.h

@@ -154,7 +154,7 @@
 #endif
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.428 2011/02/09 13:08:27 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.429 2011/02/11 00:41:37 tg Exp $");
 #endif
 #define MKSH_VERSION "R39 2011/02/09"
 
@@ -626,6 +626,7 @@ EXTERN const char T_oomem[] I__("can't allocate %lu data bytes");
 #else
 EXTERN const char T_synerr[] I__("syntax error");
 #endif
+EXTERN const char T_select[] I__("select");
 EXTERN const char T_r_fc_e_[] I__("r=fc -e -");
 #define T_fc_e_		(T_r_fc_e_ + 2)		/* "fc -e -" */
 #define Tn_fc_e_	7			/* strlen(T_fc_e_) */
@@ -794,7 +795,7 @@ struct coproc {
 EXTERN struct coproc coproc;
 
 #ifndef MKSH_NOPROSPECTOFWORK
-/* Used in jobs.c and by coprocess stuff in exec.c */
+/* used in jobs.c and by coprocess stuff in exec.c and select() calls */
 EXTERN sigset_t		sm_default, sm_sigchld;
 #endif
 
@@ -1526,6 +1527,7 @@ int c_mknod(const char **);
 int c_realpath(const char **);
 int c_rename(const char **);
 int c_cat(const char **);
+int c_sleep(const char **);
 /* histrap.c */
 void init_histvec(void);
 void hist_init(Source *);
@@ -1703,6 +1705,7 @@ int shf_vfprintf(struct shf *, const char *, va_list)
 /* syn.c */
 void initkeywords(void);
 struct op *compile(Source *);
+bool parse_usec(const char *, struct timeval *);
 /* tree.c */
 int fptreef(struct shf *, int, const char *, ...);
 char *snptreef(char *, int, const char *, ...);

syn.c

@@ -1,7 +1,7 @@
 /*	$OpenBSD: syn.c,v 1.28 2008/07/23 16:34:38 jaredy Exp $	*/
 
 /*-
- * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011
  *	Thorsten Glaser <tg@mirbsd.org>
  *
  * Provided that these terms and disclaimer and all copyright notices
@@ -22,7 +22,7 @@
 
 #include "sh.h"
 
-__RCSID("$MirOS: src/bin/mksh/syn.c,v 1.52 2010/09/14 21:26:18 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/syn.c,v 1.53 2011/02/11 00:41:38 tg Exp $");
 
 struct nesting_state {
 	int start_token;	/* token than began nesting (eg, FOR) */
@@ -405,7 +405,7 @@ get_command(int cf)
 		t = newtp((c == FOR) ? TFOR : TSELECT);
 		musthave(LWORD, ARRAYVAR);
 		if (!is_wdvarname(yylval.cp, true))
-			yyerror("%s: %s\n", c == FOR ? "for" : "select",
+			yyerror("%s: %s\n", c == FOR ? "for" : T_select,
 			    "bad identifier");
 		strdupx(t->str, ident, ATEMP);
 		nesting_push(&old_nesting, c);
@@ -736,7 +736,7 @@ const struct tokeninfo {
 	{ "case",	CASE,	true },
 	{ "esac",	ESAC,	true },
 	{ "for",	FOR,	true },
-	{ "select",	SELECT,	true },
+	{ T_select,	SELECT,	true },
 	{ "while",	WHILE,	true },
 	{ "until",	UNTIL,	true },
 	{ "do",		DO,	true },
@@ -1005,3 +1005,61 @@ dbtestp_error(Test_env *te, int offset, const char *msg)
 	}
 	syntaxerr(msg);
 }
+
+#if HAVE_SELECT
+
+#ifndef EOVERFLOW
+#ifdef ERANGE
+#define EOVERFLOW	ERANGE
+#else
+#define EOVERFLOW	EINVAL
+#endif
+#endif
+
+bool
+parse_usec(const char *s, struct timeval *tv)
+{
+	struct timeval tt;
+	int i;
+
+	tv->tv_sec = 0;
+	/* parse integral part */
+	while (ksh_isdigit(*s)) {
+		tt.tv_sec = tv->tv_sec * 10 + (*s++ - '0');
+		if (tt.tv_sec / 10 != tv->tv_sec) {
+			errno = EOVERFLOW;
+			return (true);
+		}
+		tv->tv_sec = tt.tv_sec;
+	}
+
+	tv->tv_usec = 0;
+	if (!*s)
+		/* no decimal fraction */
+		return (false);
+	else if (*s++ != '.') {
+		/* junk after integral part */
+		errno = EINVAL;
+		return (true);
+	}
+
+	/* parse decimal fraction */
+	i = 100000;
+	while (ksh_isdigit(*s)) {
+		tv->tv_usec += i * (*s++ - '0');
+		if (i == 1)
+			break;
+		i /= 10;
+	}
+	/* check for junk after fractional part */
+	while (ksh_isdigit(*s))
+		++s;
+	if (*s) {
+		errno = EINVAL;
+		return (true);
+	}
+
+	/* end of input string reached, no errors */
+	return (false);
+}
+#endif