Raise all SystemCallErrors as Trilogy::Error

CHANGELOG.md

@@ -18,6 +18,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
     Trilogy client can now accept an `:encoding` option, which will tell the connection to use the specified encoding,
     and will ensure that outgoing query strings are transcoded appropriately. If no encoding is supplied,
     utf8mb4 is used by default. #64
+  - All SystemCallErrors classified as `Trilogy::Error`.
 
 ## 2.3.0
 

contrib/ruby/ext/trilogy-ruby/cext.c

@@ -20,14 +20,14 @@
 VALUE Trilogy_CastError;
 static VALUE Trilogy_BaseConnectionError, Trilogy_ProtocolError, Trilogy_SSLError, Trilogy_QueryError,
     Trilogy_ConnectionClosedError, Trilogy_ConnectionRefusedError, Trilogy_ConnectionResetError,
-    Trilogy_TimeoutError, Trilogy_Result;
+    Trilogy_TimeoutError, Trilogy_SyscallError, Trilogy_Result;
 
 static ID id_socket, id_host, id_port, id_username, id_password, id_found_rows, id_connect_timeout, id_read_timeout,
     id_write_timeout, id_keepalive_enabled, id_keepalive_idle, id_keepalive_interval, id_keepalive_count,
     id_ivar_affected_rows, id_ivar_fields, id_ivar_last_insert_id, id_ivar_rows, id_ivar_query_time, id_password,
     id_database, id_ssl_ca, id_ssl_capath, id_ssl_cert, id_ssl_cipher, id_ssl_crl, id_ssl_crlpath, id_ssl_key,
     id_ssl_mode, id_tls_ciphersuites, id_tls_min_version, id_tls_max_version, id_multi_statement, id_multi_result,
-    id_from_code, id_connection_options;
+    id_from_code, id_from_errno, id_connection_options;
 
 struct trilogy_ctx {
     trilogy_conn_t conn;
@@ -97,8 +97,8 @@ static void trilogy_syserr_fail_str(int e, VALUE msg)
     } else if (e == ECONNRESET) {
         rb_raise(Trilogy_ConnectionResetError, "%" PRIsVALUE, msg);
     } else {
-        // TODO: All syserr should be wrapped.
-        rb_syserr_fail_str(e, msg);
+        VALUE exc = rb_funcall(Trilogy_SyscallError, id_from_errno, 2, INT2NUM(e), msg);
+        rb_exc_raise(exc);
     }
 }
 
@@ -1099,6 +1099,9 @@ RUBY_FUNC_EXPORTED void Init_cext()
     Trilogy_Result = rb_const_get(Trilogy, rb_intern("Result"));
     rb_global_variable(&Trilogy_Result);
 
+    Trilogy_SyscallError = rb_const_get(Trilogy, rb_intern("SyscallError"));
+    rb_global_variable(&Trilogy_SyscallError);
+
     Trilogy_CastError = rb_const_get(Trilogy, rb_intern("CastError"));
     rb_global_variable(&Trilogy_CastError);
 
@@ -1130,6 +1133,7 @@ RUBY_FUNC_EXPORTED void Init_cext()
     id_multi_statement = rb_intern("multi_statement");
     id_multi_result = rb_intern("multi_result");
     id_from_code = rb_intern("from_code");
+    id_from_errno = rb_intern("from_errno");
     id_ivar_affected_rows = rb_intern("@affected_rows");
     id_ivar_fields = rb_intern("@fields");
     id_ivar_last_insert_id = rb_intern("@last_insert_id");

contrib/ruby/lib/trilogy.rb

@@ -15,6 +15,27 @@ module ConnectionError
     include Error
   end
 
+  # Trilogy may raise various syscall errors, which we treat as Trilogy::Errors.
+  class SyscallError
+    ERRORS = {}
+
+    Errno.constants
+      .map { |c| Errno.const_get(c) }.uniq
+      .select { |c| c.is_a?(Class) && c < SystemCallError }
+      .each do |c|
+        errno_name = c.to_s.split('::').last
+        ERRORS[c::Errno] = const_set(errno_name, Class.new(c) { include Trilogy::Error })
+      end
+
+    ERRORS.freeze
+
+    class << self
+      def from_errno(errno, message)
+        ERRORS[errno].new(message)
+      end
+    end
+  end
+
   class BaseError < StandardError
     include Error
 
@@ -43,29 +64,14 @@ class CastError < ClientError
 
   class TimeoutError < Errno::ETIMEDOUT
     include ConnectionError
-
-    def initialize(error_message = nil, error_code = nil)
-      super
-      @error_code = error_code
-    end
   end
 
   class ConnectionRefusedError < Errno::ECONNREFUSED
     include ConnectionError
-
-    def initialize(error_message = nil, error_code = nil)
-      super
-      @error_code = error_code
-    end
   end
 
   class ConnectionResetError < Errno::ECONNRESET
     include ConnectionError
-
-    def initialize(error_message = nil, error_code = nil)
-      super
-      @error_code = error_code
-    end
   end
 
   # DatabaseError was replaced by ProtocolError, but we'll keep it around as an