Merge pull request ClickHouse#51518 from ClickHouse/qemu-chroot-fixes

Allow running in a stripped chroot environment

src/Client/ClientBase.cpp

@@ -2297,7 +2297,9 @@ void ClientBase::runInteractive()
         catch (const ErrnoException & e)
         {
             if (e.getErrno() != EEXIST)
-                throw;
+            {
+                std::cerr << getCurrentExceptionMessage(false) << '\n';
+            }
         }
     }
 

src/Client/ConnectionParameters.cpp

@@ -60,7 +60,15 @@ ConnectionParameters::ConnectionParameters(const Poco::Util::AbstractConfigurati
     quota_key = config.getString("quota_key", "");
 
     /// By default compression is disabled if address looks like localhost.
-    compression = config.getBool("compression", !isLocalAddress(DNSResolver::instance().resolveHost(host)))
+
+    /// Avoid DNS request if the host is "localhost".
+    /// If ClickHouse is run under QEMU-user with a binary for a different architecture,
+    /// and there are all listed startup dependency shared libraries available, but not the runtime dependencies of glibc,
+    /// the glibc cannot open "plugins" for DNS resolving, and the DNS resolution does not work.
+    /// At the same time, I want clickhouse-local to always work, regardless.
+    /// TODO: get rid of glibc, or replace getaddrinfo to c-ares.
+
+    compression = config.getBool("compression", host != "localhost" && !isLocalAddress(DNSResolver::instance().resolveHost(host)))
                   ? Protocol::Compression::Enable : Protocol::Compression::Disable;
 
     timeouts = ConnectionTimeouts(

src/Common/checkStackSize.cpp

@@ -27,7 +27,7 @@ static thread_local size_t max_stack_size = 0;
  * @param out_address - if not nullptr, here the address of the stack will be written.
  * @return stack size
  */
-size_t getStackSize(void ** out_address)
+static size_t getStackSize(void ** out_address)
 {
     using namespace DB;
 
@@ -54,7 +54,15 @@ size_t getStackSize(void ** out_address)
         throwFromErrno("Cannot pthread_attr_get_np", ErrorCodes::CANNOT_PTHREAD_ATTR);
 #   else
     if (0 != pthread_getattr_np(pthread_self(), &attr))
-        throwFromErrno("Cannot pthread_getattr_np", ErrorCodes::CANNOT_PTHREAD_ATTR);
+    {
+        if (errno == ENOENT)
+        {
+            /// Most likely procfs is not mounted.
+            return 0;
+        }
+        else
+            throwFromErrno("Cannot pthread_getattr_np", ErrorCodes::CANNOT_PTHREAD_ATTR);
+    }
 #   endif
 
     SCOPE_EXIT({ pthread_attr_destroy(&attr); });
@@ -83,6 +91,10 @@ __attribute__((__weak__)) void checkStackSize()
     if (!stack_address)
         max_stack_size = getStackSize(&stack_address);
 
+    /// The check is impossible.
+    if (!max_stack_size)
+        return;
+
     const void * frame_address = __builtin_frame_address(0);
     uintptr_t int_frame_address = reinterpret_cast<uintptr_t>(frame_address);
     uintptr_t int_stack_address = reinterpret_cast<uintptr_t>(stack_address);