1 files changed, 63 insertions, 1 deletions
diff --git a/src/other_tools/utils/content.hpp b/src/other_tools/utils/content.hpp
index 907af852..19877263 100644
--- a/src/other_tools/utils/content.hpp
+++ b/src/other_tools/utils/content.hpp
@@ -21,12 +21,14 @@
 #include "src/buildtool/common/user_structs.hpp"
 #include "src/buildtool/crypto/hasher.hpp"
 #include "src/buildtool/logging/log_level.hpp"
+#include "src/other_tools/just_mr/mirrors.hpp"
 #include "src/other_tools/utils/curl_easy_handle.hpp"
+#include "src/other_tools/utils/curl_url_handle.hpp"
 
 // Utilities related to the content of an archive
 
 /// \brief Fetches a file from the internet and stores its content in memory.
-/// Returns the content.
+/// \returns the content.
 [[nodiscard]] static auto NetworkFetch(std::string const& fetch_url,
                                        CAInfoPtr const& ca_info) noexcept
     -> std::optional<std::string> {
@@ -38,6 +40,66 @@
     return curl_handle->DownloadToString(fetch_url);
 }
 
+/// \brief Fetches a file from the internet and stores its content in memory.
+/// Tries not only a given remote, but also all associated remote locations.
+/// \returns the content.
+[[nodiscard]] static auto NetworkFetchWithMirrors(
+    std::string const& fetch_url,
+    std::vector<std::string> const& mirrors,
+    CAInfoPtr const& ca_info,
+    MirrorsPtr const& additional_mirrors) noexcept
+    -> std::optional<std::string> {
+    // first, try the local mirrors
+    std::optional<std::string> data{std::nullopt};
+    auto local_mirrors =
+        MirrorsUtils::GetLocalMirrors(additional_mirrors, fetch_url);
+    for (auto const& mirror : local_mirrors) {
+        if (data = NetworkFetch(mirror, ca_info); data) {
+            break;
+        }
+    }
+    if (not data) {
+        // get preferred hostnames list
+        auto preferred_hostnames =
+            MirrorsUtils::GetPreferredHostnames(additional_mirrors);
+        // try the main fetch URL, but with each of the preferred hostnames
+        for (auto const& hostname : preferred_hostnames) {
+            if (auto preferred_url =
+                    CurlURLHandle::ReplaceHostname(fetch_url, hostname)) {
+                if (data = NetworkFetch(*preferred_url, ca_info); data) {
+                    break;
+                }
+            }
+        }
+        if (not data) {
+            // now try the main fetch URL
+            if (data = NetworkFetch(fetch_url, ca_info); not data) {
+                // try the mirrors, in order, if given
+                for (auto const& mirror : mirrors) {
+                    // first use with preferred hostnames...
+                    for (auto const& hostname : preferred_hostnames) {
+                        if (auto preferred_mirror =
+                                CurlURLHandle::ReplaceHostname(mirror,
+                                                               hostname)) {
+                            if (data = NetworkFetch(*preferred_mirror, ca_info);
+                                data) {
+                                break;
+                            }
+                        }
+                    }
+                    // ...then the original mirror
+                    if (not data) {
+                        if (data = NetworkFetch(mirror, ca_info); data) {
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return data;
+}
+
 template <Hasher::HashType type>
 [[nodiscard]] static auto GetContentHash(std::string const& data) noexcept
     -> std::string {