cleanup src/linux and src/misc trees, etc.

previously, it was pretty much random which one of these trees a given
function appeared in. they have now been organized into:

src/linux: non-POSIX linux syscalls (possibly shard with other nixen)
src/legacy: various obsolete/legacy functions, mostly wrappers
src/misc: still mostly uncategorized; some misc POSIX, some nonstd
src/crypt: crypt hash functions

further cleanup will be done later.

1 files changed, 52 insertions, 0 deletions

diff --git a/src/misc/getopt_long.c b/src/misc/getopt_long.c
new file mode 100644
index 00000000..6d3a4a6e
--- /dev/null
+++ b/src/misc/getopt_long.c
@@ -0,0 +1,52 @@
+#define _GNU_SOURCE
+#include <stddef.h>
+#include <getopt.h>
+#include <stdio.h>
+
+static int __getopt_long(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx, int longonly)
+{
+	if (optind >= argc || !argv[optind] || argv[optind][0] != '-') return -1;
+	if ((longonly && argv[optind][1]) ||
+		(argv[optind][1] == '-' && argv[optind][2]))
+	{
+		int i;
+		for (i=0; longopts[i].name; i++) {
+			const char *name = longopts[i].name;
+			char *opt = argv[optind]+1;
+			if (*opt == '-') opt++;
+			for (; *name && *name == *opt; name++, opt++);
+			if (*name || (*opt && *opt != '=')) continue;
+			if (*opt == '=') {
+				if (!longopts[i].has_arg) continue;
+				optarg = opt+1;
+			} else {
+				if (longopts[i].has_arg == required_argument) {
+					if (!(optarg = argv[++optind]))
+						return ':';
+				} else optarg = NULL;
+			}
+			optind++;
+			if (idx) *idx = i;
+			if (longopts[i].flag) {
+				*longopts[i].flag = longopts[i].val;
+				return 0;
+			}
+			return longopts[i].val;
+		}
+		if (argv[optind][1] == '-') {
+			optind++;
+			return '?';
+		}
+	}
+	return getopt(argc, argv, optstring);
+}
+
+int getopt_long(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx)
+{
+	return __getopt_long(argc, argv, optstring, longopts, idx, 0);
+}
+
+int getopt_long_only(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx)
+{
+	return __getopt_long(argc, argv, optstring, longopts, idx, 1);
+}