More string stuff

src/string.c

@@ -0,0 +1,72 @@
+#include "string.h"
+
+Str str_empty(void)
+{
+    static const U8 empty_;
+    static const Str str = {(U8 *)&empty_, 0};
+    return str;
+}
+
+Str str_substr(Str str, U32 start, U32 len)
+{
+    Assert(start < str.len);
+    Assert(len <= str.len);
+
+    Str new_str = str_create(&str.str[start], len);
+    return new_str;
+}
+
+
+Str str_concat(Allocator *alloc, Str first, Str second)
+{
+    Str str;
+
+    str.len = first.len + second.len;
+    str.str = allocator_push(alloc, str.len, 1);;
+
+    MemCopy(str.str, first.str, first.len);
+    MemCopy(&str.str[first.len], second.str, second.len);
+
+    return str;
+}
+
+Str str_push(Allocator *alloc, Str str)
+{
+    U8 *mem = (U8 *)allocator_push(alloc, sizeof(Str) + str.len, alignof(Str));
+    Str *new_str = (Str *)mem;
+    new_str->len = str.len;
+    new_str->str = &mem[sizeof(Str)];
+    if (!str_is_empty(str)) {
+        MemCopy(new_str->str, str.str, str.len);
+    }
+
+    return *new_str;
+}
+
+// split @str on any byte in @separators, place split strings in @vec
+void str_split(Str str, Str separators, StrVec *vec)
+{
+    if (vec->max_len == 0 || str.len == 0) {
+        return;
+    }
+
+    U32 start_pos = 0;
+    for (U32 i = 0; i < str.len; i++) {
+        U8 byte = str.str[i];
+        if (str_find_byte(separators, byte) != -1) {
+            if (vec->len >= vec->max_len) {
+                break;
+            }
+
+            Str sub_str = str_substr(str, start_pos, i - start_pos);
+            vec->strings[vec->len] = sub_str;
+            vec->len++;
+            start_pos = i + 1;
+        }
+    }
+    if (start_pos < str.len && vec->len < vec->max_len) {
+        Str sub_str = str_substr(str, start_pos, str.len - start_pos);
+        vec->strings[vec->len] = sub_str;
+        vec->len++;
+    }
+}