From: Joel Rosdahl <joel@rosdahl.net>
Date: Sun, 23 Jul 2023 06:50:56 +0000 (+0200)
Subject: enhance: Add util::read_fd variant that returns all data at once
X-Git-Tag: v4.9~95
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=baa6cb31e70cd42d7edd22524cefff66c866da0d;p=thirdparty%2Fccache.git

enhance: Add util::read_fd variant that returns all data at once
---

diff --git a/src/util/file.cpp b/src/util/file.cpp
index 1647da49f..4c739ea1d 100644
--- a/src/util/file.cpp
+++ b/src/util/file.cpp
@@ -204,6 +204,17 @@ read_fd(int fd, DataReceiver data_receiver)
   return {};
 }
 
+tl::expected<Bytes, std::string>
+read_fd(int fd)
+{
+  Bytes output;
+  return read_fd(fd,
+                 [&](auto data) {
+                   output.insert(output.end(), data.begin(), data.end());
+                 })
+    .transform([&] { return output; });
+}
+
 #ifdef _WIN32
 static bool
 has_utf16_le_bom(std::string_view text)
diff --git a/src/util/file.hpp b/src/util/file.hpp
index c65514b04..3ee0e1f06 100644
--- a/src/util/file.hpp
+++ b/src/util/file.hpp
@@ -18,6 +18,7 @@
 
 #pragma once
 
+#include <util/Bytes.hpp>
 #include <util/TimePoint.hpp>
 #include <util/types.hpp>
 
@@ -59,10 +60,15 @@ tl::expected<void, std::string> fallocate(int fd, size_t new_size);
 // Return how much a file of `size` bytes likely would take on disk.
 uint64_t likely_size_on_disk(uint64_t size);
 
-// Read data from `fd` until end of file and call `data_receiver` with the read
-// data. Returns an error if the underlying read(2) call returned -1.
+// Read data from `fd` until end of file and call `data_receiver` repeatedly
+// with the read data. Returns an error if the underlying read(2) call returned
+// -1.
 tl::expected<void, std::string> read_fd(int fd, DataReceiver data_receiver);
 
+// Read data from `fd`. Returns an error if the underlying read(2) call returned
+// -1.
+tl::expected<util::Bytes, std::string> read_fd(int fd);
+
 // Return contents of file at  `path`.
 //
 // `T` should be `util::Bytes` or `std::vector<uint8_t>` for binary data and