intcmp(1): new tool; npc(1): new tool; scrut(1): new tool; str(1): new tool; strcmp(1): new tool; tests: added POSIX compatibility test and C compiler compatibility test; Makefile: converted to GNUmakefile; README: added README; docs: added docs

src/str.c

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2023 DTB <trinity@trinity.moe>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ *
+ * This program is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU Affero General Public License as published by the Free
+ * Software Foundation, either version 3 of the License, or (at your option) any
+ * later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see https://www.gnu.org/licenses/.
+ */
+
+#include <ctype.h>
+#include <stddef.h> /* NULL */
+#include <stdio.h> /* fprintf(3) */
+#include <string.h> /* strcmp(3) */
+#if !defined EX_USAGE
+#	include <sysexits.h>
+#endif
+
+static char *program_name = "str";
+
+static struct {
+	char *name;
+	int (*f)(int);
+}ctypes[] = {
+	{ "isalnum", isalnum },
+	{ "isalpha", isalpha },
+	{ "isblank", isblank },
+	{ "iscntrl", iscntrl },
+	{ "isdigit", isdigit },
+	{ "isxdigit", isxdigit },
+	{ "isgraph", isgraph },
+	{ "islower", islower },
+	{ "isprint", isprint },
+	{ "ispunct", ispunct },
+	{ "isspace", isspace },
+	{ "isupper", isupper }
+};
+
+int main(int argc, char *argv[]){
+	int ctype;
+	int i;
+	int r;
+
+	if(argc >= 3){
+		for(ctype = 0; ctype < (sizeof ctypes) / (sizeof *ctypes);
+				++ctype)
+			if(strcmp(argv[1], ctypes[ctype].name) == 0)
+				goto pass;
+	}
+
+	fprintf(stderr, "Usage: %s [type] [string...]\n",
+		argv[0] == NULL ? program_name : argv[0]);
+
+	return EX_USAGE;
+
+pass:	for(argv += 2, r = 1; *argv != NULL; ++argv)
+		for(i = 0; argv[0][i] != '\0'; ++i)
+			/* First checks if argv[0][i] is valid ASCII; ctypes(3)
+			 * don't handle non-ASCII.
+			 * This is bad. */
+			if(argv[0][i] < 0x80 && !ctypes[ctype].f(argv[0][i]))
+				return 1;
+			else
+				r = 0;
+
+	return r;
+}