[k2] support file_get_contents (#1592)

Author: Shamzik

runtime-light/stdlib/file/file-system-functions.h

@@ -16,9 +16,7 @@
 #include <unistd.h>
 #include <utility>
 
-#include "runtime-common/core/allocator/script-allocator.h"
 #include "runtime-common/core/runtime-core.h"
-#include "runtime-common/core/std/containers.h"
 #include "runtime-common/stdlib/array/array-functions.h"
 #include "runtime-common/stdlib/string/string-functions.h"
 #include "runtime-light/coroutine/task.h"
@@ -204,40 +202,24 @@ inline Optional<string> f$file_get_contents(const string& stream) noexcept {
 }
 
 inline Optional<array<string>> f$file(const string& name) noexcept {
-  struct stat stat_buf {};
-
-  auto expected_file{kphp::fs::file::open(name.c_str(), "r")};
+  auto expected_file{kphp::fs::file::open({name.c_str(), name.size()}, "r")};
   if (!expected_file.has_value()) {
     return false;
   }
-  if (!k2::stat({name.c_str(), name.size()}, std::addressof(stat_buf)).has_value()) {
-    return false;
-  }
-  if (!S_ISREG(stat_buf.st_mode)) {
-    kphp::log::warning("regular file expected as first argument in function file, \"{}\" is given", name.c_str());
-    return false;
-  }
 
-  const size_t size{static_cast<size_t>(stat_buf.st_size)};
-  if (size > string::max_size()) {
-    kphp::log::warning("file \"{}\" is too large", name.c_str());
+  auto expected_file_content{std::move(*expected_file).get_contents()};
+  if (!expected_file_content.has_value()) {
+    kphp::log::warning("file::get_contents returned code {}", expected_file_content.error());
     return false;
   }
-
-  kphp::stl::vector<std::byte, kphp::memory::script_allocator> file_content;
-  file_content.resize(size);
-  {
-    auto file{std::move(*expected_file)};
-    if (auto expected_read_result{file.read(file_content)}; !expected_read_result.has_value() || *expected_read_result < size) {
-      return false;
-    }
-  }
+  auto file_content{std::move(*expected_file_content)};
+  const size_t size{file_content.size()};
 
   array<string> result;
   int32_t prev{-1};
   for (size_t i{0}; i < size; i++) {
-    if (static_cast<char>(file_content[i]) == '\n' || i + 1 == size) {
-      result.push_back(string{reinterpret_cast<char*>(file_content.data()) + prev + 1, static_cast<string::size_type>(i - prev)});
+    if (file_content[i] == '\n' || i + 1 == size) {
+      result.push_back(file_content.substr(prev + 1, static_cast<string::size_type>(i - prev)));
       prev = i;
     }
   }

runtime-light/stdlib/file/resource.h

@@ -13,6 +13,8 @@
 #include <memory>
 #include <span>
 #include <string_view>
+#include <sys/mman.h>
+#include <sys/stat.h>
 #include <tuple>
 #include <type_traits>
 #include <utility>
@@ -45,6 +47,73 @@ inline constexpr std::string_view UDP_SCHEME_PREFIX = "udp://";
 
 // ================================================================================================
 
+class mmap {
+  k2::descriptor m_descriptor{k2::INVALID_PLATFORM_DESCRIPTOR};
+  void* m_addr{nullptr};
+  size_t m_length{};
+
+  mmap(k2::descriptor descriptor, void* addr, size_t length) noexcept
+      : m_descriptor{descriptor},
+        m_addr{addr},
+        m_length{length} {}
+
+public:
+  mmap(mmap&& other) noexcept
+      : m_descriptor{std::exchange(other.m_descriptor, k2::INVALID_PLATFORM_DESCRIPTOR)},
+        m_addr{std::exchange(other.m_addr, nullptr)},
+        m_length{std::exchange(other.m_length, {})} {}
+
+  mmap& operator=(mmap&& other) noexcept {
+    if (this != std::addressof(other)) {
+      std::ignore = close();
+      m_descriptor = std::exchange(other.m_descriptor, k2::INVALID_PLATFORM_DESCRIPTOR);
+      m_addr = std::exchange(other.m_addr, nullptr);
+      m_length = std::exchange(other.m_length, {});
+    }
+    return *this;
+  }
+
+  ~mmap() {
+    std::ignore = close();
+  }
+
+  mmap(const mmap&) = delete;
+  mmap& operator=(const mmap&) = delete;
+
+  static auto create(size_t length, int32_t prot, int32_t flags, k2::descriptor fd, uint64_t offset) noexcept -> std::expected<mmap, int32_t>;
+
+  auto madvise(int32_t advise) noexcept -> std::expected<void, int32_t>;
+  auto data() const noexcept -> std::span<const std::byte>;
+  auto close() noexcept -> std::expected<void, int32_t>;
+};
+
+inline auto mmap::create(size_t length, int32_t prot, int32_t flags, k2::descriptor fd, uint64_t offset) noexcept -> std::expected<mmap, int32_t> {
+  k2::descriptor descriptor{k2::INVALID_PLATFORM_DESCRIPTOR};
+  auto* addr{k2::mmap(std::addressof(descriptor), nullptr, length, prot, flags, fd, offset)};
+  if (addr == MAP_FAILED) [[unlikely]] {
+    return std::unexpected{k2::errno_efault};
+  }
+  return mmap{descriptor, addr, length};
+}
+
+inline auto mmap::madvise(int32_t advise) noexcept -> std::expected<void, int32_t> {
+  return k2::madvise(m_addr, m_length, advise);
+}
+
+inline auto mmap::data() const noexcept -> std::span<const std::byte> {
+  return {reinterpret_cast<const std::byte*>(m_addr), m_length};
+}
+
+inline auto mmap::close() noexcept -> std::expected<void, int32_t> {
+  if (m_descriptor == k2::INVALID_PLATFORM_DESCRIPTOR) [[unlikely]] {
+    return std::unexpected{k2::errno_enodev};
+  }
+  k2::free_descriptor(std::exchange(m_descriptor, k2::INVALID_PLATFORM_DESCRIPTOR));
+  return {};
+}
+
+// ================================================================================================
+
 struct resource : public refcountable_polymorphic_php_classes<may_be_mixed_base> {
   const char* get_class() const noexcept final {
     return "resource";
@@ -146,7 +215,29 @@ inline auto file::pread(std::span<std::byte> buf, uint64_t offset) noexcept -> s
 }
 
 inline auto file::get_contents() noexcept -> std::expected<string, int32_t> {
-  return std::unexpected{m_descriptor != k2::INVALID_PLATFORM_DESCRIPTOR ? k2::errno_efault : k2::errno_enodev};
+  struct stat stat_buf {};
+
+  if (auto expected{k2::fstat(m_descriptor, std::addressof(stat_buf))}; !expected.has_value()) {
+    return std::unexpected{expected.error()};
+  }
+  if (!S_ISREG(stat_buf.st_mode)) {
+    return std::unexpected{k2::errno_einval};
+  }
+
+  const size_t size{static_cast<size_t>(stat_buf.st_size)};
+  if (size > string::max_size()) {
+    return std::unexpected{k2::errno_erange};
+  }
+
+  auto expected_mmap{kphp::fs::mmap::create(size, PROT_READ, MAP_PRIVATE | MAP_POPULATE, m_descriptor, 0)};
+  if (!expected_mmap.has_value()) {
+    return std::unexpected{expected_mmap.error()};
+  }
+
+  auto& mmap{*expected_mmap};
+  std::ignore = mmap.madvise(MADV_SEQUENTIAL);
+  auto data{mmap.data()};
+  return string{reinterpret_cast<const char*>(data.data()), static_cast<string::size_type>(data.size())};
 }
 
 inline auto file::flush() noexcept -> std::expected<void, int32_t> {

tests/phpt/dl/464_gzip.php

@@ -1,4 +1,4 @@
-@ok k2_skip
+@ok
 <?php
 #ifndef KPHP
 if(!function_exists('gzdecode')){