Add str_join

src/string.c

@@ -32,9 +32,7 @@ Str str_concat(Allocator *alloc, Str first, Str second)
 Str str_push(Allocator *alloc, Str str)
 {
     U8 *mem = (U8 *)allocator_push(alloc, str.len, 1);
-    if (!str_is_empty(str)) {
-        MemCopy(mem, str.str, str.len);
-    }
+    MemCopy(mem, str.str, str.len);
 
     return str_create(mem, str.len);
 }
@@ -80,8 +78,21 @@ Str str_ascii_trim(Str str)
     return new_str;
 }
 
-S64 str_substr(Str haystack, Str to_find)
+S64 str_substr(Str haystack, Str needle)
 {
+    if (needle.len == 0) {
+        return 0;
+    }
+
+    if (needle.len == 0) {
+        return str_find_byte(haystack, needle.str[0]);
+    }
+
+    U8 *found = MemFind(haystack.str, haystack.len, needle.str, needle.len);
+    if (found != NULL) {
+        return (S64)(found - haystack.str);
+    }
+
     return -1;
 }
 
@@ -112,3 +123,33 @@ void str_split(Str str, Str separators, StrVec *vec)
         vec->len++;
     }
 }
+
+Str str_join(Allocator *allocator, StrVec strings, Str separator)
+{
+
+    U32 str_len = 0;
+
+    for (U32 i = 0; i < strings.len; i++) {
+        str_len += strings.strings[i].len;
+    }
+    if (strings.len > 0) {
+        str_len += separator.len * (strings.len - 1);
+    }
+
+    U8 *joined_str = allocator_push(allocator, str_len, 1);
+    if (strings.len > 0) {
+        U32 pos = 0;
+        Str *str = &strings.strings[0];
+        MemCopy(&joined_str[pos], str->str, str->len);
+        pos += str->len;
+        for (U32 i = 1; i < strings.len; i++) {
+            str = &strings.strings[i];
+            MemCopy(&joined_str[pos], separator.str, separator.len);
+            pos += separator.len;
+            MemCopy(&joined_str[pos], str->str, str->len);
+            pos += str->len;
+        }
+    }
+
+    return str_create(joined_str, str_len);
+}