add test.c (thanks Random832)

Makefile

@@ -41,6 +41,7 @@ SRC = \
 	sort.c     \
 	tail.c     \
 	tee.c      \
+	test.c     \
 	touch.c    \
 	true.c     \
 	tty.c      \

config.mk

@@ -9,7 +9,7 @@ MANPREFIX = $(PREFIX)/share/man
 #CC = musl-gcc
 LD = $(CC)
 CPPFLAGS = -D_POSIX_C_SOURCE=200112L
-CFLAGS   = -Os -ansi -Wall -Wextra -pedantic $(CPPFLAGS)
+CFLAGS   = -Os -ansi -Wall -pedantic $(CPPFLAGS)
 LDFLAGS  = -static #-s
 
 #CC = tcc

test.c

@@ -0,0 +1,123 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include "util.h"
+
+static bool unary(const char *, const char *);
+static void usage(void);
+static bool binary(const char *, const char *, const char *);
+
+static const char *progname;
+
+int
+main(int argc, char *argv[])
+{
+	bool ret, not = false;
+
+	progname = argv[0];
+
+	/* [ ... ] alias */
+	if(!strcmp(argv[0], "[")) {
+		if(strcmp(argv[argc-1], "]") != 0)
+			usage();
+		argc--;
+	}
+	if(argc > 1 && !strcmp(argv[1], "!")) {
+		not = true;
+		argv++;
+		argc--;
+	}
+	switch(argc) {
+	case 2:
+		ret = *argv[1] != '\0';
+		break;
+	case 3:
+		ret = unary(argv[1], argv[2]);
+		break;
+	case 4:
+		ret = binary(argv[1], argv[2], argv[3]);
+		break;
+	default:
+		usage();
+	}
+	if(not)
+		ret = !ret;
+	return ret ? EXIT_SUCCESS : EXIT_FAILURE;
+}
+
+bool
+unary(const char *op, const char *arg)
+{
+	struct stat st;
+	int r;
+
+	if(op[0] != '-' || op[1] == '\0' || op[2] != '\0')
+		usage();
+	switch(op[1]) {
+	case 'b': case 'c': case 'd': case 'e': case 'f':
+	case 'g': case 'p': case 'S': case 's': case 'u':
+		if((r = stat(arg, &st)) == -1)
+			return false; /* -e */
+		switch(op[1]) {
+		case 'b':
+			return S_ISBLK(st.st_mode);
+		case 'c':
+			return S_ISCHR(st.st_mode);
+		case 'd':
+			return S_ISDIR(st.st_mode);
+		case 'e':
+			return true;
+		case 'f':
+			return S_ISREG(st.st_mode);
+		case 'g':
+			return st.st_mode & S_ISGID;
+		case 'p':
+			return S_ISFIFO(st.st_mode);
+		case 'S':
+			return S_ISSOCK(st.st_mode);
+		case 's':
+			return st.st_size > 0;
+		case 'u':
+			return st.st_mode & S_ISUID;
+		}
+	case 'h': case 'L':
+		return lstat(arg, &st) == 0 && S_ISLNK(st.st_mode);
+	case 'n':
+		return arg[0] != '\0';
+	case 't':
+		return isatty((int)estrtol(arg, 0));
+	case 'r':
+		return access(arg, R_OK) == 0;
+	case 'w':
+		return access(arg, W_OK) == 0;
+	case 'x':
+		return access(arg, X_OK) == 0;
+	case 'z':
+		return arg[0] == '\0';
+	default:
+		usage();
+	}
+	return false; /* should not reach */
+}
+
+void
+usage(void)
+{
+	const char *ket = (progname[0] == '[') ? " ]" : "";
+
+	fprintf(stderr, "usage: %s string%s\n", progname, ket);
+	fprintf(stderr, "       %s [!] [-bcdefghLnprSstuwxz] string%s\n",  progname, ket);
+	fprintf(stderr, "       %s [!] string1 comparison-op string2%s\n", progname, ket);
+	exit(EXIT_FAILURE);
+}
+
+bool
+binary(const char *arg1, const char *op, const char *arg2)
+{
+	eprintf("not yet implemented\n");
+	return false;
+}