From: Aki Tuomi <aki.tuomi@dovecot.fi>
Date: Sat, 10 Mar 2018 16:20:32 +0000 (+0200)
Subject: lib: Add str_nescape
X-Git-Tag: 2.3.9~2055
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9b40bf3a6a085130639c0100f5003838e47ebfee;p=thirdparty%2Fdovecot%2Fcore.git

lib: Add str_nescape

For partial escaping
---

diff --git a/src/lib/strescape.c b/src/lib/strescape.c
index 85dc08ea78..6312367f2a 100644
--- a/src/lib/strescape.c
+++ b/src/lib/strescape.c
@@ -4,28 +4,27 @@
 #include "str.h"
 #include "strescape.h"
 
-const char *str_escape(const char *str)
+const char *str_nescape(const void *str, size_t len)
 {
-	const char *p;
+	const unsigned char *s = str, *p = str;
 	string_t *ret;
-
 	/* see if we need to quote it */
-	for (p = str; *p != '\0'; p++) {
+	for (p = str; (size_t)(p - s) < len; p++) {
 		if (IS_ESCAPED_CHAR(*p))
 			break;
 	}
 
-	if (*p == '\0')
+	if (p == (s + len))
 		return str;
 
 	/* quote */
-	ret = t_str_new((size_t) (p - str) + 128);
-	str_append_n(ret, str, (size_t) (p - str));
+	ret = t_str_new((size_t)(p - s) + 128);
+	str_append_n(ret, s, (size_t)(p - s));
 
-	for (; *p != '\0'; p++) {
+	for (; (size_t)(p - s) < len; p++) {
 		if (IS_ESCAPED_CHAR(*p))
 			str_append_c(ret, '\\');
-		str_append_c(ret, *p);
+		str_append_data(ret, p, 1);
 	}
 	return str_c(ret);
 }
diff --git a/src/lib/strescape.h b/src/lib/strescape.h
index c910a26825..b4658ce21c 100644
--- a/src/lib/strescape.h
+++ b/src/lib/strescape.h
@@ -3,8 +3,15 @@
 
 #define IS_ESCAPED_CHAR(c) ((c) == '"' || (c) == '\\' || (c) == '\'')
 
-/* escape all '\', '"' and "'" characters */
-const char *str_escape(const char *str);
+/* escape all '\', '"' and "'" characters,
+   this is nul safe */
+const char *str_nescape(const void *str, size_t len);
+
+/* escape string */
+static inline const char *str_escape(const char *str)
+{
+	return str_nescape(str, strlen(str));
+}
 
 /* remove all '\' characters, append to given string */
 void str_append_unescaped(string_t *dest, const void *src, size_t src_size);
diff --git a/src/lib/test-strescape.c b/src/lib/test-strescape.c
index 2f47b113ac..b918062d1d 100644
--- a/src/lib/test-strescape.c
+++ b/src/lib/test-strescape.c
@@ -71,6 +71,16 @@ static void test_str_escape(void)
 			   "\\\\\\\\\\\"\\\"\\\'\\\'") == 0);
 	test_end();
 
+	test_begin("str_nescape");
+
+	escaped = str_nescape("\"escape only first but not 'this'", 10);
+	test_assert(strcmp(escaped, "\\\"escape on") == 0);
+
+	escaped = str_nescape("\"hello\"\0\"world\"", 15);
+	test_assert(memcmp(escaped, "\\\"hello\\\"\0\\\"world\\\"", 19) == 0);
+
+	test_end();
+
 	str = t_str_new(256);
 	test_begin("str_unescape");
 	for (i = 0; i < N_ELEMENTS(unesc); i++) {