tal/str: add tal_strcat().

[ccan] / ccan / tal / str / str.c

diff --git a/ccan/tal/str/str.c b/ccan/tal/str/str.c
index b7df54c42af704eee6e1fbd9d941205ec54a2235..4606b47e3356955f7989389b9729db33c5b3b71f 100644 (file)
--- a/ccan/tal/str/str.c
+++ b/ccan/tal/str/str.c
@@ -81,6 +81,31 @@ char *tal_vasprintf(const tal_t *ctx, const char *fmt, va_list ap)
        return buf;
 }
 
+char *tal_strcat(const tal_t *ctx, const char *s1, const char *s2)
+{
+       size_t len1, len2;
+       char *ret;
+
+       if (unlikely(!s2) && taken(s2)) {
+               if (taken(s1))
+                       tal_free(s1);
+               return NULL;
+       }
+       /* We have to let through NULL for take(). */
+       len1 = s1 ? strlen(s1) : 0;
+       len2 = strlen(s2);
+
+       /* We use tal_dup_ here to avoid attaching a length property. */
+       ret = tal_dup_(ctx, s1, 1, len1, len2 + 1, false,
+                      TAL_LABEL(char, "[]"));
+       if (likely(ret))
+               memcpy(ret + len1, s2, len2 + 1);
+
+       if (taken(s2))
+               tal_free(s2);
+       return ret;
+}
+
 char **tal_strsplit(const tal_t *ctx,
                    const char *string, const char *delims, enum strsplit flags)
 {