Add error code generator

Author: sunaoka

.gitattributes

@@ -4,3 +4,5 @@
 /.travis.yml export-ignore
 /phpunit.xml export-ignore
 /tests export-ignore
+/tools export-ignore
+/Makefile export-ignore

Makefile

@@ -0,0 +1,13 @@
+SOURCE := https://raw.githubusercontent.com/postgres/postgres/master/src/backend/utils/errcodes.txt
+TARGET := $(CURDIR)/src/PostgresError.php
+GENERATOR := php $(CURDIR)/tools/generator.php
+
+all: clean $(TARGET)
+
+$(TARGET):
+	curl -s $(SOURCE) | $(GENERATOR) > $@
+
+clean:
+	-$(RM) $(TARGET)
+
+.PHONY: all clean

tools/generator.php

@@ -0,0 +1,29 @@
+<?php
+
+$codes = array();
+$const = array();
+
+while ($row = fgets(STDIN)) {
+    if (preg_match('/^([0-9A-Z]{5}) +[SWE] +[^ ]+? +([a-z_]+)$/', $row, $matches)) {
+        $key = strtoupper($matches[2]);
+        if (isset($codes[$key])) {
+            $key .= '_EXCEPTION';
+        }
+        $codes[$key] = '';
+        $const[] = "    const {$key} = '{$matches[1]}';";
+    }
+}
+
+$const = implode(PHP_EOL, $const);
+
+echo <<<EOD
+<?php
+
+namespace Sunaoka\PostgresError;
+
+class PostgresError
+{
+$const
+}
+
+EOD;