Extract git reference parsing to a shared library

These utility functions can be shared between the git and github fetchers.

1 files changed, 25 insertions, 0 deletions

diff --git a/src/libfetchers/git-utils.cc b/src/libfetchers/git-utils.cc
new file mode 100644
index 000000000..060077098
--- /dev/null
+++ b/src/libfetchers/git-utils.cc
@@ -0,0 +1,25 @@
+#include "git-utils.hh"
+
+#include <regex>
+
+std::optional<std::string> parseListReferenceHeadRef(std::string_view line) {
+    const static std::regex head_ref_regex("^ref: ([^\\s]+)\\t+HEAD$");
+    std::match_results<std::string_view::const_iterator> match;
+    if (std::regex_match(line.cbegin(), line.cend(), match, head_ref_regex)) {
+        return match[1];
+    } else {
+        return std::nullopt;
+    }
+}
+
+std::optional<std::string> parseListReferenceForRev(std::string_view rev, std::string_view line) {
+    const static std::regex rev_regex("^([^\\t]+)\\t+(.*)$");
+    std::match_results<std::string_view::const_iterator> match;
+    if (!std::regex_match(line.cbegin(), line.cend(), match, rev_regex)) {
+        return std::nullopt;
+    }
+    if (rev != match[2].str()) {
+        return std::nullopt;
+    }
+    return match[1];
+}