Add xstring module - bounded string builder with three valued comparator

Makefile-ccan

@@ -122,7 +122,8 @@ MODS_WITH_SRC := aga \
 	time \
 	timer \
 	ttxml \
-	wwviaudio
+	wwviaudio \
+	xstring
 
 MODS:=$(MODS_WITH_SRC) $(MODS_NO_SRC)
 

ccan/xstring/LICENSE

+../../licenses/APACHE-2
\ No newline at end of file

ccan/xstring/_info

+#include "config.h"
+#include <stdio.h>
+#include <string.h>
+
+/**
+ * xstring - bounded string builder with three valued comparator
+ *
+ * xstring handles string concatenation to a buffer, flagging truncation.
+ * Additions can be transactional, where the addition wholly succeeds or the buffer is reterminated at its prior length.
+ * Once flagged, no further additions are allowed.
+ * Clearing reuses the buffer from the beginning.
+ *
+ * When comparing two xstrings, the truncation state is taken into account.
+ * If either is truncated, an equality test returns unknown (-1).
+ * Testing if x contains y returns unknown (-1) if y is truncated.
+ * If x is whole, the test returns true (1) or false (0) appropriately.
+ * If x is truncated, the test returns true (1) if the known portion of x contains y, and unknown (-1) otherwise.
+ *
+ * The structure members are intended for direct access.
+ *
+ * Example:
+ *	// demo - break long lines
+ *	#include <string.h>
+ *	#include <stdio.h>
+ *	#include <unistd.h>
+ *	#include <err.h>
+ *	#include <fcntl.h>
+ *	#include <sys/types.h>
+ *	#include <sys/stat.h>
+ *	#include <sys/mman.h>
+ *
+ *	#include "ccan/xstring/xstring.h"
+ *
+ *	#define MAXLEN 80
+ *	#define MARGIN 10
+ *	int main(int argc, char *argv[])
+ *	{
+ *		char buf[BUFSIZ];
+ *		xstring _x, *x = &_x;
+ *		struct stat sb;
+ *		int fd, span, lnlen;
+ *		char *map, *p, *q;
+ *
+ *		xstrInit(x, buf, sizeof(buf), 0);
+ *		assert(sizeof(buf) > MAXLEN);
+ *
+ *		if (argc != 2) return 1;
+ *
+ *		if ((fd = open(argv[1], O_RDONLY)) == -1)
+ *			err(1, "open");
+ *		if (fstat(fd, &sb) == -1)
+ *			err(1, "stat");
+ *		if ((map = mmap(NULL, sb.st_size + 1, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0)) == MAP_FAILED)
+ *			err(1, "mmap");
+ *		map[sb.st_size] = '\n';
+ *
+ *		for (p = map, lnlen = 0; p < map + sb.st_size; ) {
+ *			span = strcspn(p, " \t\n") + 1;
+ *
+ *			if (lnlen + span > MAXLEN) {
+ *				span = MAXLEN - lnlen;
+ *				xstrAddSubsT(x, p, span, "\n", 1, NULL);
+ *			}
+ *			else
+ *				xstrAddSubT(x, p, span);
+ *
+ *			if (x->truncated) {
+ *				fputs(x->str, stdout);
+ *				xstrClear(x);
+ *				continue; // p unchanged
+ *			}
+ *
+ *			q = x->str + x->len - 1;
+ *			if (lnlen + MARGIN > MAXLEN)
+ *				*q = '\n';
+ *
+ *			lnlen = *q == '\n' ? 0 : lnlen + span;
+ *			p += span;
+ *		}
+ *
+ *		if (x->len)
+ *			fputs(x->str, stdout);
+ *
+ *		return 0;
+ *	}
+ *
+ * License: APACHE-2
+ * Author: Dan Good <dan@dancancode.com>
+ */
+int main(int argc, char *argv[])
+{
+	/* Expect exactly one argument */
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/failtest\n");
+		return 0;
+	}
+
+	return 1;
+}

ccan/xstring/test/run.c

+#include <ccan/xstring/xstring.h>
+/* Include the C files directly. */
+#include <ccan/xstring/xstring.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	plan_tests(70);
+
+	{ //12
+		char buf[4] = { 'a', 'a', 'a', 'a' };
+		xstring a;
+
+		ok1(xstrInit(&a, buf, sizeof(buf), 0) == 0);
+		ok1(a.str == buf && a.len == 0 && a.cap == sizeof(buf) && a.truncated == 0 && a.str[0] == '\0');
+
+		buf[0] = 'a';
+		ok1(xstrInit(&a, buf, sizeof(buf), 1) == -1);
+		ok1(a.str == buf && a.len == 3 && a.cap == sizeof(buf) && a.truncated == -1 && strcmp(a.str, "aaa") == 0);
+
+		ok1(xstrInit(&a, buf, sizeof(buf), 1) == 0);
+		ok1(a.str == buf && a.len == 3 && a.cap == sizeof(buf) && a.truncated == 0 && strcmp(a.str, "aaa") == 0);
+
+		xstrClear(&a);
+		ok1(xstrAddChar(&a, '1') == 0 && a.truncated == 0 && strcmp(a.str, "1") == 0);
+		ok1(xstrAddChar(&a, '2') == 0 && a.truncated == 0 && strcmp(a.str, "12") == 0);
+		ok1(xstrAddChar(&a, '3') == 0 && a.truncated == 0 && strcmp(a.str, "123") == 0);
+		ok1(xstrAddChar(&a, '\0') == 0 && a.truncated == 0 && strcmp(a.str, "123") == 0);
+		ok1(xstrAddChar(&a, '4') == -1 && a.truncated == -1 && strcmp(a.str, "123") == 0);
+		ok1(xstrAddChar(&a, '5') == -1 && a.truncated == -1 && strcmp(a.str, "123") == 0);
+	}
+
+	{ //21
+		char buf[10];
+		xstring _x, *x = &_x;
+
+		ok1(xstrInit(x, buf, sizeof(buf), 0) == 0);
+		ok1(x->str == buf && x->len == 0 && x->cap == sizeof(buf) && x->truncated == 0 && *x->str == '\0');
+
+		ok1(xstrAdd(x, "") == 0 && x->len == 0 && x->truncated == 0 && *x->str == '\0');
+		ok1(xstrAdd(x, NULL) == 0 && x->len == 0 && x->truncated == 0 && *x->str == '\0');
+
+		ok1(xstrAdd(x, "foo") == 0 && x->len == 3 && x->truncated == 0 && strcmp(x->str, "foo") == 0);
+		ok1(xstrAdd(x, "bar") == 0 && x->len == 6 && x->truncated == 0 && strcmp(x->str, "foobar") == 0);
+		ok1(xstrAdd(x, "baz") == 0 && x->len == 9 && x->truncated == 0 && strcmp(x->str, "foobarbaz") == 0);
+		ok1(xstrAdd(x, "oof") == -1 && x->len == 9 && x->truncated == -1 && strcmp(x->str, "foobarbaz") == 0);
+		ok1(xstrAdd(x, "rab") == -1 && x->len == 9 && x->truncated == -1 && strcmp(x->str, "foobarbaz") == 0);
+
+		xstrClear(x);
+		ok1(x->str == buf && x->len == 0 && x->cap == sizeof(buf) && x->truncated == 0 && *x->str == '\0');
+		ok1(xstrAdd(x, "foobarbazoof") == -1 && x->len == 9 && x->truncated == -1 && strcmp(x->str, "foobarbaz") == 0);
+
+		xstrClear(x);
+		ok1(xstrAdd(x, "foo") == 0 && x->len == 3 && x->truncated == 0 && strcmp(x->str, "foo") == 0);
+		ok1(xstrAddT(x, "foobarbazoof") == -1 && x->len == 3 && x->truncated == -1 && strcmp(x->str, "foo") == 0);
+		xstrClear(x);
+		ok1(xstrAddT(&_x, "foobarbazoof") == -1 && x->len == 0 && x->truncated == -1 && *x->str == '\0');
+
+		xstrClear(x);
+		ok1(xstrCat(x, "foo", "bar", "baz", NULL) == 0 && x->len == 9 && x->truncated == 0 && strcmp(x->str, "foobarbaz") == 0);
+		xstrClear(x);
+		ok1(xstrCat(x, "foo", "bar", "baz", "oof", NULL) == -1 && x->len == 9 && x->truncated == -1 && strcmp(x->str, "foobarbaz") == 0);
+		xstrClear(x);
+		ok1(xstrCatT(x, "foo", "bar", "baz", "oof", NULL) == -1 && x->len == 0 && x->truncated == -1 && *x->str == '\0');
+		xstrClear(x);
+		ok1(xstrCatT(&_x, "foo", "bar", "baz", "oof", NULL) == -1 && x->len == 0 && x->truncated == -1 && *x->str == '\0');
+
+		xstrClear(x);
+		ok1(xstrJoin(x, ",", "fo", "ba", "ba", NULL) == 0 && x->len == 8 && x->truncated == 0 && strcmp(x->str, "fo,ba,ba") == 0);
+		xstrClear(x);
+		ok1(xstrJoin(x, ",", "foobarbaz", "oof", NULL) == -1 && x->len == 9 && x->truncated == -1 && strcmp(x->str, "foobarbaz") == 0);
+		xstrClear(x);
+		ok1(xstrJoin(x, ",", "foobarba", "oof", NULL) == -1 && x->len == 9 && x->truncated == -1 && strcmp(x->str, "foobarba,") == 0);
+	}
+
+	{ //9
+		char buf[10];
+		xstring _x, *x = &_x;
+
+		ok1(xstrInit(x, buf, sizeof(buf), 0) == 0);
+		ok1(xstrAddSub(x, NULL, 0) == 0 && x->len == 0 && x->truncated == 0 && *x->str == '\0');
+		ok1(xstrAddSub(x, "foo", 0) == 0 && x->len == 0 && x->truncated == 0 && *x->str == '\0');
+		ok1(xstrAddSub(x, "foobar", 3) == 0 && x->len == 3 && x->truncated == 0 && strcmp(x->str, "foo") == 0);
+		ok1(xstrAddSub(x, "foobarbaz", 7) == -1 && x->len == 3 && x->truncated == -1 && strcmp(x->str, "foo") == 0);
+
+		xstrClear(x);
+		ok1(xstrAddSubs(x, "aa", 1, "bbb", 2, NULL) == 0 && x->len == 3 && x->truncated == 0 && strcmp(x->str, "abb") == 0);
+		ok1(xstrAddSubs(x, "cccccccc", 7, NULL) == -1 && x->len == 3 && x->truncated == -1 && strcmp(x->str, "abb") == 0);
+		xstrClear(x);
+		ok1(xstrAddSubsT(x, "aa", 1, "bbb", 2, NULL) == 0 && x->len == 3 && x->truncated == 0 && strcmp(x->str, "abb") == 0);
+		ok1(xstrAddSubsT(x, "cccccccc", 7, NULL) == -1 && x->len == 3 && x->truncated == -1 && strcmp(x->str, "abb") == 0);
+	}
+
+	{ //28
+		char a[10], b[10];
+		xstring _x, *x = &_x;
+		xstring _y, *y = &_y;
+
+		xstrInit(x, a, sizeof(a), 0);
+		xstrInit(y, b, sizeof(b), 0);
+		xstrAdd(x, "foobarbaz");
+		xstrAdd(y, "foobarbaz");
+		ok1(xstrEq3(x, y) == 1);
+		ok1(xstrEq(x, y) == 1);
+		ok1(xstrContains3(x, y, 1) == 1);
+		ok1(xstrContains(x, y, 1) == 1);
+		xstrAddChar(x, 'x');
+		ok1(xstrEq3(x, y) == -1);
+		ok1(xstrEq(x, y) == 0);
+		ok1(xstrContains3(x, y, 1) == 1);
+		ok1(xstrContains(x, y, 1) == 1);
+		xstrClear(x);
+		xstrAdd(x, "foobarbaz");
+		xstrAddChar(y, 'x');
+		ok1(xstrEq3(x, y) == -1);
+		ok1(xstrEq(x, y) == 0);
+		ok1(xstrContains3(x, y, 1) == -1);
+		ok1(xstrContains(x, y, 1) == 0);
+		xstrClear(y);
+		xstrAdd(y, "Foobarbaz");
+		ok1(xstrEq3(x, y) == 0);
+		ok1(xstrEq(x, y) == 0);
+
+		xstrClear(x);
+		xstrClear(y);
+		xstrAdd(x, "foo");
+		xstrAdd(y, "foobarbaz");
+		ok1(xstrContains3(x, y, 1) == 0);
+		ok1(xstrContains(x, y, 1) == 0);
+		ok1(xstrContains3(y, x, 1) == 1);
+		ok1(xstrContains(y, x, 1) == 1);
+		ok1(xstrContains3(y, x, 0) == 1);
+		ok1(xstrContains(y, x, 0) == 1);
+		ok1(xstrContains3(y, x, -1) == 0);
+		ok1(xstrContains(y, x, -1) == 0);
+		xstrClear(x);
+		xstrAdd(x, "baz");
+		ok1(xstrContains3(y, x, -1) == 1);
+		ok1(xstrContains(y, x, -1) == 1);
+		ok1(xstrContains3(y, x, 0) == 1);
+		ok1(xstrContains(y, x, 0) == 1);
+		ok1(xstrContains3(y, x, 1) == 0);
+		ok1(xstrContains(y, x, 1) == 0);
+	}
+
+	return exit_status();
+}

ccan/xstring/test/run2.c

+#include <ccan/failtest/failtest_override.h>
+#include <ccan/failtest/failtest.h>
+#include <ccan/xstring/xstring.h>
+/* Include the C files directly. */
+#include <ccan/xstring/xstring.c>
+#include <ccan/tap/tap.h>
+
+unsigned last_fail_line;
+
+enum failtest_result once_only(struct tlist_calls *history)
+{
+	const struct failtest_call *tail = tlist_tail(history, list);
+
+	if (tail->line == last_fail_line)
+		return FAIL_DONT_FAIL;
+
+	last_fail_line = tail->line;
+	return FAIL_OK;
+}
+
+int main(int argc, char *argv[])
+{
+	failtest_init(argc, argv);
+	failtest_hook = once_only;
+	plan_tests(3);
+
+	xstring *x;
+
+	ok1((x = xstrNew(100)) != NULL); // fail first malloc
+	if (x) xstrFree(x);
+
+	ok1((x = xstrNew(100)) != NULL); // fail second malloc
+	if (x) xstrFree(x);
+
+	ok1((x = xstrNew(0)) == NULL && errno == EINVAL);
+
+	failtest_exit(exit_status());
+}

ccan/xstring/xstring.c

+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#define _XOPEN_SOURCE 700
+#include <string.h>
+#include "xstring.h"
+
+xstring *xstrNew(const size_t size)
+{
+	char *str;
+	xstring *x;
+
+	if (size < 1) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	str = malloc(size);
+	if (!str)
+		return NULL;
+
+	x = malloc(sizeof(struct xstring));
+	if (!x) {
+		free(str);
+		return NULL;
+	}
+
+	xstrInit(x, str, size, 0);
+	return x;
+}
+
+int xstrInit(xstring *x, char *str, const size_t size, int keep)
+{
+	assert(x && str && size > 0);
+	memset(x, 0, sizeof(*x));
+
+	x->str = str;
+	x->cap = size;
+
+	if (keep) {
+		x->len = strnlen(str, x->cap);
+		if (x->cap == x->len) {
+			x->truncated = -1;
+			x->len--;
+		}
+	}
+
+	*(x->str + x->len) = '\0';
+
+	return x->truncated;
+}
+
+int xstrAddChar(xstring *x, const char c)
+{
+	assert(x);
+
+	if (x->truncated || c == '\0')
+		return x->truncated;
+
+	if (x->len + 1 < x->cap) {
+		char *p = x->str + x->len;
+		*p++ = c;
+		*p = '\0';
+		x->len++;
+	}
+	else
+		x->truncated = -1;
+
+	return x->truncated;
+}
+
+int xstrAdd(xstring *x, const char *src)
+{
+	char *p, *q, *s;
+
+	assert(x);
+
+	if (x->truncated || !src || *src == '\0')
+		return x->truncated;
+
+	for (s = (char *)src,
+	     p = x->str + x->len,
+	     q = x->str + x->cap - 1;
+	     *s != '\0' && p < q; p++, s++) {
+		*p = *s;
+	}
+
+	*p = '\0';
+	x->len = (size_t) (p - x->str);
+
+	if (*s != '\0')
+		x->truncated = -1;
+
+	return x->truncated;
+}
+
+int xstrAddSub(xstring *x, const char *src, size_t len)
+{
+	assert(x);
+
+	if (x->truncated || !src || len == 0)
+		return x->truncated;
+
+	if (x->len + len + 1 > x->cap)
+		return x->truncated = -1;
+
+	memcpy(x->str + x->len, src, len);
+
+	x->len += len;
+	*(x->str + x->len) = '\0';
+
+	return x->truncated;
+}
+
+int xstrCat(xstring *x, ...)
+{
+	va_list ap;
+	char *s;
+
+	assert(x);
+	va_start(ap, x);
+	while ((s = va_arg(ap, char *)) != NULL) {
+		if (xstrAdd(x, s) == -1)
+			break;
+	}
+	va_end(ap);
+	return x->truncated;
+}
+
+int xstrJoin(xstring *x, const char *sep, ...)
+{
+	va_list ap;
+	char *s;
+	int i;
+
+	assert(x && sep);
+	va_start(ap, sep);
+	for (i = 0; (s = va_arg(ap, char *)) != NULL; i++) {
+		if (i && xstrAdd(x, sep) == -1)
+			break;
+		if (xstrAdd(x, s) == -1)
+			break;
+	}
+	va_end(ap);
+	return x->truncated;
+}
+
+int xstrAddSubs(xstring *x, ...)
+{
+	va_list ap;
+	char *s;
+
+	assert(x);
+	va_start(ap, x);
+	while ((s = va_arg(ap, char *)) != NULL) {
+		size_t n = va_arg(ap, size_t);
+		if (xstrAddSub(x, s, n) == -1)
+			break;
+	}
+	va_end(ap);
+	return x->truncated;
+}
+
+int xstrEq3(xstring *x, xstring *y)
+{
+	assert(x && y);
+
+	if (x->truncated || y->truncated)
+		return unknown;
+
+	return x->len == y->len && xstrContains3(x, y, 1);
+}
+
+/* Does the first string contain the second */
+int xstrContains3(xstring *x, xstring *y, int where)
+{
+	int b;
+
+	assert(x && y && where >= -1 && where <= 1);
+
+	if (y->truncated)
+		return unknown;
+
+	if (x->len < y->len)
+		return 0;
+
+	switch (where) {
+	case -1:
+		b = strncmp(x->str + x->len - y->len, y->str, y->len) == 0;
+		break;
+	case 0:
+		b = strstr(x->str, y->str) != NULL;
+		break;
+	case 1:
+		b = strncmp(x->str, y->str, y->len) == 0;
+		break;
+	}
+
+	return b ? 1 : x->truncated ? unknown : 0;
+}
+
+void xstrFree(xstring *x)
+{
+	assert(x);
+	free(x->str);
+	free(x);
+}

ccan/xstring/xstring.h

+#ifndef _XSTRING_H
+#define _XSTRING_H 1
+
+#include <assert.h>
+#include <sys/types.h>
+
+/**
+ * struct xstring - string metadata
+ * @str: pointer to buf
+ * @len: current length of buf contents
+ * @cap: maximum capacity of buf
+ * @truncated: -1 indicates truncation
+ */
+typedef struct xstring {
+	char *str;
+	size_t len;
+	size_t cap;
+	int truncated;
+} xstring;
+
+/**
+ * xstrNew - mallocs and inits
+ * @size: size of buffer to allocate
+ *
+ * mallocs both buffer and struct, calls xstrInit
+ *
+ * Return: ptr to xstring or NULL
+ */
+xstring *xstrNew(const size_t size);
+
+/**
+ * xstrInit - initialize an xstring struct
+ * @x: pointer to xstring
+ * @str: buffer to manage
+ * @size: size of str
+ * @keep: if !0, keep existing contents of str;
+ *        otherwise, str[0] = '\0'
+ *
+ * Return: x->truncated
+ */
+int xstrInit(xstring *x, char *str, const size_t size, int keep);
+
+/**
+ * xstrClear - clear xstring
+ * @x: pointer to xstring
+ *
+ * This sets x->len and x->truncated to 0 and str[0] to '\0';
+ *
+ * Return: x->truncated (always 0)
+ */
+#define xstrClear(x) (xstrInit((x), (x)->str, (x)->cap, 0))
+
+/**
+ * xstrAddChar - add a single character
+ * @x: pointer to xstring
+ * @c: character to append
+ *
+ * Return: x->truncated
+ */
+int xstrAddChar(xstring *x, const char c);
+
+/**
+ * xstrAdd - append a string
+ * @x: pointer to xstring
+ * @src: string to append
+ *
+ * Append as much from src as fits - if not all, flag truncation.
+ *
+ * Return: x->truncated
+ */
+int xstrAdd(xstring *x, const char *src);
+
+/**
+ * xstrAddSub - append a substring
+ * @x: pointer to xstring
+ * @src: string to append
+ * @len: length of substring
+ *
+ * Append substring and '\0' if len fits, otherwise flag truncation.
+ *
+ * Return: x->truncated
+ */
+int xstrAddSub(xstring *x, const char *src, size_t len);
+
+/** xstrCat - append multiple strings
+ * @x: pointer to xstring
+ * @...: one or more strings followed by NULL
+ *
+ * Run xstrAdd for each string.
+ *
+ * Return: x->truncated
+ */
+int xstrCat(xstring *x, ...);
+
+/** xstrJoin - append multiple strings joined by sep
+ * @x: pointer to xstring
+ * @sep: separator string
+ * @...: one or more strings followed by NULL
+ *
+ * Run xstrAdd for each string and append sep between each pair.
+ *
+ * Return: x->truncated
+ */
+int xstrJoin(xstring *x, const char *sep, ...);
+
+/**
+ * xstrAddSubs - append multiple substrings
+ * @x: pointer to xstring
+ * @...: one or more pairs of string and length followed by NULL
+ *
+ * Run xstrAddSub for each pair of string and length.
+ *
+ * Return: x->truncated
+ */
+int xstrAddSubs(xstring *x, ...);
+
+#define transact(x, y)  ({ \
+	size_t last; \
+	int ret; \
+	assert((x)); \
+	last = (x)->len; \
+	if ((ret = (y)) == -1) { \
+		(x)->len = last; \
+		*((x)->str + (x)->len) = '\0'; \
+	} \
+	ret; \
+})
+
+/**
+ * xstrAddT - append a string as a transaction
+ * @x: pointer to xstring
+ * @src: string to append
+ *
+ * Run xstrAdd. Reterminate at inital length if truncation occurs.
+ *
+ * Return: x->truncated
+ */
+#define xstrAddT(x, y)        transact(x, xstrAdd((x), y))
+
+/** xstrCatT - append multiple strings as one transaction
+ * @x: pointer to xstring
+ * @...: one or more strings followed by NULL
+ *
+ * Run xstrCat. Reterminate at inital length if truncation occurs.
+ *
+ * Return: x->truncated
+ */
+#define xstrCatT(x, y...)     transact(x, xstrCat((x) , ## y))
+
+/** xstrJoinT - append multiple strings joined by sep as one transaction
+ * @x: pointer to xstring
+ * @sep: separator string
+ * @...: one or more strings followed by NULL
+ *
+ * Run xstrJoin. Reterminate at inital length if truncation occurs.
+ *
+ * Return: x->truncated
+ */
+#define xstrJoinT(x, y...)    transact(x, xstrJoin((x) , ## y))
+
+/**
+ * xstrAddSubsT - append multiple substrings as one transaction
+ * @x: pointer to xstring
+ * @...: one or more pairs of string and length followed by NULL
+ *
+ * Run xstrAddSubs. Reterminate at inital length if truncation occurs.
+ *
+ * Return: x->truncated
+ */
+#define xstrAddSubsT(x, y...) transact(x, xstrAddSubs((x) , ## y))
+
+/**
+ * xstrAddSubT - same as xstrAddSub
+ */
+// addsub is already transactional
+#define xstrAddSubT xstrAddSub
+
+#define unknown -1
+
+/**
+ * xstrEq3 - test if two strings are equal
+ * @x: pointer to xstring
+ * @y: pointer to xstring
+ *
+ * Return true (1) if the strings held by x and y match and no truncation has occurred.
+ * Return unknown (-1) if either is flagged as truncated.
+ * Return false (0) otherwise.
+ *
+ * Return: -1, 0, or 1
+ */
+int xstrEq3(xstring *x, xstring *y);
+
+/**
+ * xstrEq - test if two strings are equal
+ * @x: pointer to xstring
+ * @y: pointer to xstring
+ *
+ * Same as xstrEq3, but return false (0) for unknown (-1).
+ *
+ * Return: 0 or 1
+ */
+#define xstrEq(x, y) (xstrEq3((x), (y)) == 1)
+
+/**
+ * xstrContains3 - test if first string contains second
+ * @x: pointer to xstring
+ * @y: pointer to xstring
+ * @where: -1 (ends), 0 (anywhere), 1 (begins)
+ *
+ * If neither x nor y are truncated, returns true (1) or false (0).
+ * If y is truncated, return unknown (-1).
+ * If x is truncated, return true (1) if known portion of x contains y, unknown (-1) otherwise.
+ *
+ * Return: -1, 0, or 1
+ */
+int xstrContains3(xstring *x, xstring *y, int where);
+
+/**
+ * xstrContains3 - test if first string contains second
+ * @x: pointer to xstring
+ * @y: pointer to xstring
+ * @where: -1 (ends), 0 (anywhere), 1 (begins)
+ *
+ * Same as xstrContains3, but return false (0) for unknown (-1).
+ *
+ * Return: 0 or 1
+ */
+#define xstrContains(x, y, w) (xstrContains3((x), (y), (w)) == 1)
+
+/**
+ * xstrFree - free malloced memory
+ * @x: pointer to xstring
+ */
+void xstrFree(xstring *x);
+
+#endif