Merge branch 'master' into referenceablePaths

src/libutil/error.hh

@@ -74,6 +74,8 @@ struct AbstractPos
     virtual void print(std::ostream & out) const = 0;
 
     std::optional<LinesOfCode> getCodeLines() const;
+
+    virtual ~AbstractPos() = default;
 };
 
 std::ostream & operator << (std::ostream & str, const AbstractPos & pos);

src/libutil/json-impls.hh

@@ -0,0 +1,14 @@
+#pragma once
+
+#include "nlohmann/json_fwd.hpp"
+
+// Following https://github.com/nlohmann/json#how-can-i-use-get-for-non-default-constructiblenon-copyable-types
+#define JSON_IMPL(TYPE)                                                \
+    namespace nlohmann {                                               \
+        using namespace nix;                                           \
+        template <>                                                    \
+        struct adl_serializer<TYPE> {                                  \
+            static TYPE from_json(const json & json);                  \
+            static void to_json(json & json, TYPE t);                  \
+        };                                                             \
+    }

src/libutil/monitor-fd.hh

@@ -22,27 +22,38 @@ public:
     {
         thread = std::thread([fd]() {
             while (true) {
-              /* Wait indefinitely until a POLLHUP occurs. */
-              struct pollfd fds[1];
-              fds[0].fd = fd;
-              /* This shouldn't be necessary, but macOS doesn't seem to
-                 like a zeroed out events field.
-                 See rdar://37537852.
-              */
-              fds[0].events = POLLHUP;
-              auto count = poll(fds, 1, -1);
-              if (count == -1) abort(); // can't happen
-              /* This shouldn't happen, but can on macOS due to a bug.
-                 See rdar://37550628.
+                /* Wait indefinitely until a POLLHUP occurs. */
+                struct pollfd fds[1];
+                fds[0].fd = fd;
+                /* Polling for no specific events (i.e. just waiting
+                   for an error/hangup) doesn't work on macOS
+                   anymore. So wait for read events and ignore
+                   them. */
+                fds[0].events =
+                    #ifdef __APPLE__
+                    POLLRDNORM
+                    #else
+                    0
+                    #endif
+                    ;
+                auto count = poll(fds, 1, -1);
+                if (count == -1) abort(); // can't happen
+                /* This shouldn't happen, but can on macOS due to a bug.
+                   See rdar://37550628.
 
-                 This may eventually need a delay or further
-                 coordination with the main thread if spinning proves
-                 too harmful.
-               */
-              if (count == 0) continue;
-              assert(fds[0].revents & POLLHUP);
-              triggerInterrupt();
-              break;
+                   This may eventually need a delay or further
+                   coordination with the main thread if spinning proves
+                   too harmful.
+                */
+                if (count == 0) continue;
+                if (fds[0].revents & POLLHUP) {
+                    triggerInterrupt();
+                    break;
+                }
+                /* This will only happen on macOS. We sleep a bit to
+                   avoid waking up too often if the client is sending
+                   input. */
+                sleep(1);
             }
         });
     };

src/libutil/regex-combinators.hh

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <string_view>
+
+namespace nix::regex {
+
+// TODO use constexpr string building like
+// https://github.com/akrzemi1/static_string/blob/master/include/ak_toolkit/static_string.hpp
+
+static inline std::string either(std::string_view a, std::string_view b)
+{
+    return std::string { a } + "|" + b;
+}
+
+static inline std::string group(std::string_view a)
+{
+    return std::string { "(" } + a + ")";
+}
+
+static inline std::string many(std::string_view a)
+{
+    return std::string { "(?:" } + a + ")*";
+}
+
+static inline std::string list(std::string_view a)
+{
+    return std::string { a } + many(group("," + a));
+}
+
+}

src/libutil/tests/tests.cc

@@ -311,6 +311,42 @@ namespace nix {
         ASSERT_THROW(base64Decode("cXVvZCBlcm_0IGRlbW9uc3RyYW5kdW0="), Error);
     }
 
+    /* ----------------------------------------------------------------------------
+     * getLine
+     * --------------------------------------------------------------------------*/
+
+    TEST(getLine, all) {
+        {
+            auto [line, rest] = getLine("foo\nbar\nxyzzy");
+            ASSERT_EQ(line, "foo");
+            ASSERT_EQ(rest, "bar\nxyzzy");
+        }
+
+        {
+            auto [line, rest] = getLine("foo\r\nbar\r\nxyzzy");
+            ASSERT_EQ(line, "foo");
+            ASSERT_EQ(rest, "bar\r\nxyzzy");
+        }
+
+        {
+            auto [line, rest] = getLine("foo\n");
+            ASSERT_EQ(line, "foo");
+            ASSERT_EQ(rest, "");
+        }
+
+        {
+            auto [line, rest] = getLine("foo");
+            ASSERT_EQ(line, "foo");
+            ASSERT_EQ(rest, "");
+        }
+
+        {
+            auto [line, rest] = getLine("");
+            ASSERT_EQ(line, "");
+            ASSERT_EQ(rest, "");
+        }
+    }
+
     /* ----------------------------------------------------------------------------
      * toLower
      * --------------------------------------------------------------------------*/