Add getopt(1).

Includes new tests.

lib/portability.h

@@ -105,6 +105,9 @@ static inline char *basename(char *path) { return __xpg_basename(path); }
 char *strcasestr(const char *haystack, const char *needle);
 #endif // defined(glibc)
 
+// getopt_long(), getopt_long_only(), and struct option.
+#include <getopt.h>
+
 #if !defined(__GLIBC__)
 // POSIX basename.
 #include <libgen.h>

tests/getopt.test

@@ -0,0 +1,44 @@
+#!/bin/bash
+
+[ -f testing.sh ] && . testing.sh
+
+#testing "name" "command" "result" "infile" "stdin"
+
+function test_getopt() {
+  testcmd "$1" "$1" "$2\n" "" ""
+}
+
+# Traditional behavior was to take the first argument as OPTSTR and not quote.
+test_getopt "a b c" " -- b c"
+test_getopt "a -a b c" " -a -- b c"
+test_getopt "a -- -a b c" " -- -a b c"
+
+# Modern -o mode.
+test_getopt "-o a -- " " --"
+test_getopt "-o a -- -a b c" " -a -- 'b' 'c'"
+test_getopt "-o a: -- -a b c" " -a 'b' -- 'c'"
+
+# Long options (--like --this).
+test_getopt "-o a -l long -- -a --long a" " -a --long -- 'a'"
+test_getopt "-o a -l one -l two -- -a --one --two" " -a --one --two --"
+test_getopt "-o a -l one,two -- -a --one --two" " -a --one --two --"
+# -l arg: (required)
+test_getopt "-o a -l one: -- -a --one arg" " -a --one 'arg' --"
+# -l arg:: (optional)
+test_getopt "-o a -l one:: -- -a --one" " -a --one '' --"
+test_getopt "-o a -l one:: -- -a --one arg" " -a --one '' -- 'arg'"
+test_getopt "-o a -l one:: -- -a --one=arg" " -a --one 'arg' --"
+
+# "Alternative" long options (-like -this but also --like --this).
+test_getopt "-o a -a -l long -- -long --long a" " --long --long -- 'a'"
+
+# -u lets you avoid quoting even with modern -o.
+test_getopt "-u -o a: -- -a b c" " -a b -- c"
+
+# Do we quote quotes right?
+test_getopt "-o a -- \"it\'s\"" " -- 'it\'\''s'"
+test_getopt "-o a -u -- \"it\'s\"" " -- it\'s"
+
+# Odds and ends.
+testcmd "-T" "-T ; echo \$?" "4\n" "" ""
+testcmd "-n" "-n unlikely a -x 2>&1 | grep -o unlikely:" "unlikely:\n" "" ""

toys/pending/getopt.c

@@ -0,0 +1,104 @@
+/* getopt.c - Parse command-line options
+ *
+ * Copyright 2019 The Android Open Source Project
+
+USE_GETOPT(NEWTOY(getopt, "^(alternative)a(name)n:(options)o:(long)(longoptions)l*Tu", TOYFLAG_USR|TOYFLAG_BIN))
+
+config GETOPT
+  bool "getopt"
+  default y
+  help
+    usage: getopt [OPTIONS] [--] ARG...
+
+    Parse command-line options for use in shell scripts.
+
+    -a	Allow long options starting with a single -.
+    -l OPTS	Specify long options.
+    -n NAME	Command name for error messages.
+    -o OPTS	Specify short options.
+    -T	Test whether this is a modern getopt.
+    -u	Output options unquoted.
+*/
+
+#define FOR_getopt
+#include "toys.h"
+
+GLOBALS(
+  struct arg_list *l;
+  char *o, *n;
+)
+
+static void out(char *s)
+{
+  if (FLAG(u)) printf(" %s", s);
+  else {
+    printf(" '");
+    for (; *s; s++) {
+      if (*s == '\'') printf("'\\''");
+      else putchar(*s);
+    }
+    printf("'");
+  }
+}
+
+static char *parse_long_opt(void *data, char *str, int len)
+{
+  struct option **lopt_ptr = data, *lopt = *lopt_ptr;
+
+  // Trailing : or :: means this option takes a required or optional argument.
+  // no_argument = 0, required_argument = 1, optional_argument = 2.
+  for (lopt->has_arg = 0; len>0 && str[len-1] == ':'; lopt->has_arg++) len--;
+  if (!len || lopt->has_arg>2) return str;
+
+  lopt->name = xstrndup(str, len);
+
+  (*lopt_ptr)++;
+  return 0;
+}
+
+void getopt_main(void)
+{
+  int argc = toys.optc+1;
+  char **argv = xzalloc(sizeof(char *)*(argc+1));
+  struct option *lopts = xzalloc(sizeof(struct option)*argc), *lopt = lopts;
+  int i = 0, j = 0, ch;
+
+  if (FLAG(T)) {
+    toys.exitval = 4;
+    return;
+  }
+
+  comma_args(TT.l, &lopt, "bad -l", parse_long_opt);
+  argv[j++] = TT.n ? TT.n : "getopt";
+
+  // Legacy mode: don't quote output and take the first argument as OPTSTR.
+  if (!FLAG(o)) {
+    toys.optflags |= FLAG_u;
+    TT.o = toys.optargs[i++];
+    if (!TT.o) error_exit("no OPTSTR");
+    --argc;
+  }
+
+  while (i<toys.optc) argv[j++] = toys.optargs[i++];
+
+  // BSD getopts don't honor argv[0] (for -n), so handle errors ourselves.
+  opterr = 0;
+  optind = 1;
+  while ((ch = (FLAG(a)?getopt_long_only:getopt_long)(argc, argv, TT.o,
+          lopts, &i)) != -1) {
+    if (ch == '?') {
+      fprintf(stderr, "%s: invalid option '%c'\n", argv[0], optopt);
+      toys.exitval = 1;
+    } else if (!ch) {
+      printf(" --%s", lopts[i].name);
+      if (lopts[i].has_arg) out(optarg ? optarg : "");
+    } else {
+      printf(" -%c", ch);
+      if (optarg) out(optarg);
+    }
+  }
+
+  printf(" --");
+  for (; optind<argc; optind++) out(argv[optind]);
+  printf("\n");
+}