Add slice and make_empty.HEADmain

1 files changed, 13 insertions, 3 deletions

diff --git a/cstring/include/cstring.h b/cstring/include/cstring.h
index b07dad6..8ed4e93 100644
--- a/cstring/include/cstring.h
+++ b/cstring/include/cstring.h
@@ -43,6 +43,8 @@
     }                                                                         \
   }                                                                           \
                                                                               \
+  static inline STRING STRING##_make_empty() { return (STRING){0}; }          \
+                                                                              \
   static inline STRING STRING##_dirname(const STRING path) {                  \
     STRING str = path;                                                        \
     for (int i = str.length - 1; i >= 0; --i) {                               \
@@ -79,9 +81,8 @@
       const STRING a, const char* b, const size_t b_length) {                 \
     ASSERT(a.length + b_length + 1 <= SIZE);                                  \
     STRING str = {0};                                                         \
-    strlcpy(str.str, a.str, SIZE);                                            \
-    strlcpy(str.str + a.length, b, SIZE - a.length);                          \
-    str.length = a.length + b_length;                                         \
+    STRING##_append_cstr_len(&str, a.str, a.length);                          \
+    STRING##_append_cstr_len(&str, b, b_length);                              \
     return str;                                                               \
   }                                                                           \
                                                                               \
@@ -97,6 +98,15 @@
     return STRING##_concat(STRING##_concat_cstr(a, "/"), b);                  \
   }                                                                           \
                                                                               \
+  static inline STRING STRING##_slice(                                        \
+      const STRING a, const size_t start, const size_t end) {                 \
+    ASSERT(start < a.length);                                                 \
+    ASSERT(end <= a.length);                                                  \
+    STRING str = {0};                                                         \
+    strlcpy(str.str, &a.str[start], end - start);                             \
+    return str;                                                               \
+  }                                                                           \
+                                                                              \
   static inline bool STRING##_eq_cstr_len(                                    \
       const STRING a, const char* b, size_t b_length) {                       \
     return (a.length == b_length) && strncmp(a.str, b, a.length) == 0;        \