More work on xargs: bugfix and tests.

scripts/test/xargs.test

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+[ -f testing.sh ] && . testing.sh
+
+#testing "name" "command" "result" "infile" "stdin"
+
+testing "xargs" "xargs && echo yes" "hello\nyes\n" "" "hello"
+testing "xargs spaces" "xargs" \
+	"one two three four\n" "" "one two\tthree  \nfour\n\n"
+
+testing "xargs -n 0" "xargs -n 0 2>/dev/null || echo ok" "ok\n" \
+	"" "one \ntwo\n three"
+testing "xargs -n 2" "xargs -n 2" "one two\nthree\n" "" "one \ntwo\n three"
+testing "xargs -n exact match" "xargs -n 3" "one two three\n" "" "one two three"
+testing "xargs2" "xargs -n2" "one two\nthree four\nfive\n" "" \
+	"one two three four five"
+testing "xargs -s too long" "xargs -s 9 echo 2>/dev/null || echo ok" \
+	"one\ntwo\nok\n" "" "one two three"
+testing "xargs -s 13" "xargs -s 13 echo" "one two\nthree\n" "" "one \ntwo\n three"
+testing "xargs -s 12" "xargs -s 12 echo" "one\ntwo\nthree\n" "" "one \ntwo\n three"
+
+touch one two three
+testing "xargs command -opt" "xargs -n2 ls -1" "one\ntwo\nthree\n" "" \
+	"one two three"
+rm one two three
+
+exit
+
+testing "xargs -n exact match" 
+testing "xargs -s exact match"
+testing "xargs -s 0"
+testing "xargs -s impossible"
+
+# xargs command_not_found - returns 127
+# xargs false - returns 1

toys/xargs.c

@@ -6,7 +6,7 @@
  *
  * See http://opengroup.org/onlinepubs/9699919799/utilities/xargs.html
 
-USE_XARGS(NEWTOY(xargs, "n#s#0", TOYFLAG_USR|TOYFLAG_BIN))
+USE_XARGS(NEWTOY(xargs, "^I:E:L#ptxrn#<1s#0", TOYFLAG_USR|TOYFLAG_BIN))
 
 config XARGS
 	bool "xargs"
@@ -16,9 +16,17 @@ config XARGS
 
 	  Run command line one or more times, appending arguments from stdin.
 
+	  If command exits with 255, don't launch another even if arguments remain.
+
 	  -s	Size in bytes per command line
 	  -n	Max number of arguments per command
 	  -0	Each argument is NULL terminated, no whitespace or quote processing
+	  #-p	Prompt for y/n from tty before running each command
+	  #-t	Trace, print command line to stderr
+	  #-x	Exit if can't fit everything in one command
+	  #-r	Don't run command with empty input
+	  #-L	Max number of lines of input per command
+	  #-E	stop at line matching string
 */
 
 #include "toys.h"
@@ -64,7 +72,7 @@ static char *handle_entries(char *data, char **entry)
 			}
 
 			if (TT.entries >= TT.max_entries && TT.max_entries)
-				return *s ? (char *)1: s;
+				return *s ? s : (char *)1;
 
 			if (!*s) break;
 			save = s;
@@ -106,10 +114,11 @@ void xargs_main(void)
 		bytes += strlen(toys.optargs[entries]);
 
 	// Loop through exec chunks.
-	while (!done) {
+	while (data || !done) {
+		char **out;
+
 		TT.entries = 0;
 		TT.bytes = bytes;
-		char **out;
 
 		// Loop reading input
 		for (;;) {