Major updates:

- A lotta cleanup
- BEd command parser rewrite
- Vase class removed
- Proper IO system.
- A lot more.

src/internal/vase/storage/append.cc

@@ -0,0 +1,72 @@
+#include "internal/vase/vase.h"
+
+namespace bed::internal::vase {
+AppendStorage::AppendStorage(std::filesystem::path base_dir) {
+  base_dir /= "tapp.XXXXXX";
+  char *s = strdup(base_dir.c_str());
+  fd = mkstemp(s);
+  if (fd == -1)
+    throw std::runtime_error("mkstemp failed");
+  unlink(s);
+  free(s);
+  allocated_capacity = 1ull << 30;
+  if (ftruncate(fd, allocated_capacity) == -1)
+    throw std::runtime_error("ftruncate failed");
+  buf = (char *)mmap(nullptr, allocated_capacity, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+  if (buf == MAP_FAILED)
+    throw std::runtime_error("mmap failed");
+}
+
+AppendStorage::~AppendStorage() {
+  if (buf && buf != MAP_FAILED)
+    munmap(buf, allocated_capacity);
+  if (fd != -1)
+    close(fd);
+}
+
+void AppendStorage::grow(uint64_t len) {
+  if (current_size + len > allocated_capacity) {
+    uint64_t new_capacity = allocated_capacity * 2;
+    if (new_capacity < current_size + len)
+      new_capacity = current_size + len + (1ull << 30);
+    if (ftruncate(fd, new_capacity) == -1)
+      throw std::runtime_error("ftruncate failed");
+#if defined(__linux__)
+    void *new_buf = mremap(buf, allocated_capacity, new_capacity, MREMAP_MAYMOVE);
+    if (new_buf == MAP_FAILED)
+      throw std::runtime_error("mremap failed");
+#else
+    munmap(buf, allocated_capacity);
+    void *new_buf = mmap(nullptr, new_capacity, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+    if (new_buf == MAP_FAILED)
+      throw std::runtime_error("mmap failed");
+#endif
+    allocated_capacity = new_capacity;
+    buf = (char *)new_buf;
+  }
+}
+
+uint64_t AppendStorage::append(const char c) {
+  grow(1);
+  buf[current_size++] = c;
+  return current_size - 1;
+}
+
+uint64_t AppendStorage::append(const char *text, uint64_t len) {
+  grow(len);
+  memcpy(buf + current_size, text, len);
+  uint64_t old_pos = current_size;
+  current_size += len;
+  return old_pos;
+}
+
+const char *AppendStorage::read(uint64_t pos) {
+  if (pos >= current_size)
+    return nullptr;
+  return buf + pos;
+}
+
+uint64_t AppendStorage::length() {
+  return current_size;
+}
+} // namespace bed::internal::vase