[tlo-parsing] dynamically allocate buffer for tlo file (#905)

common/tlo-parsing/tlo-parser.cpp

@@ -24,31 +24,35 @@ tlo_parser::tlo_parser(const char *tlo_path) :
     error("%s", strerror(errno));
     return;
   }
-  len = fread(data, 1, sizeof(data), f);
+
+  std::fseek(f, 0, SEEK_END);
+  auto file_size = std::ftell(f);
+  std::rewind(f);
+  data.resize(file_size);
+
+  len = fread(data.data(), 1, file_size, f);
   std::fclose(f);
-  if (!(len > 0 && len < MAX_SCHEMA_LEN)) {
+  if (!(len > 0 && len == file_size)) {
     error("Error while reading file %s", tlo_path);
     return;
   }
   tl_sch = std::make_unique<tl_scheme>();
 }
 
-tlo_parser::~tlo_parser() = default;
-
 std::string tlo_parser::get_string() {
   check_pos(4);
-  size_t len = *reinterpret_cast<unsigned char *>(data + pos);
+  size_t len = *reinterpret_cast<unsigned char *>(data.data() + pos);
   if (len < 254) {
     pos += 1;
   } else {
-    len = *reinterpret_cast<unsigned int *>(data + pos);
+    len = *reinterpret_cast<unsigned int *>(data.data() + pos);
     pos += 4;
   }
   check_pos(len);
   size_t old_pos = pos;
   pos += len;
   pos += (-pos & 3);
-  return {data + old_pos, len};
+  return {data.data() + old_pos, len};
 }
 
 void tlo_parser::check_pos(size_t size) {

common/tlo-parsing/tlo-parser.h

@@ -7,6 +7,7 @@
 #include <cstring>
 #include <memory>
 #include <string>
+#include <vector>
 
 namespace vk {
 namespace tlo_parsing {
@@ -17,17 +18,14 @@ struct expr_base;
 struct tl_scheme;
 
 struct tlo_parser {
-  static constexpr unsigned int MAX_SCHEMA_LEN = 4 * 1024 * 1024;
-
   tlo_parser() = default;
   explicit tlo_parser(const char *tlo_path);
-  ~tlo_parser();
 
   template<typename T>
   T get_value() {
     check_pos(sizeof(T));
     T res{};
-    memcpy(&res, data + pos, sizeof(T));
+    memcpy(&res, data.data() + pos, sizeof(T));
     pos += sizeof(T);
     return res;
   }
@@ -49,7 +47,7 @@ struct tlo_parser {
   size_t len;
   size_t pos;
   std::unique_ptr<tl_scheme> tl_sch;
-  char data[MAX_SCHEMA_LEN + 1];
+  std::vector<char> data;
 };
 
 } // namespace tlo_parsing