Adds a simple tool to generate new escape tables

.gitignore

@@ -199,6 +199,7 @@ CTAGS
 tools/http_load/http_load
 tools/jtest/jtest
 tools/trafficserver.pc
+tools/escape_mapper/escape_mapper
 
 BUILDS
 DEBUG

proxy/logging/LogUtils.cc

@@ -296,6 +296,8 @@ escapify_url_common(Arena *arena, char *url, size_t len_in, int *len_out, char *
   // historically this is what the traffic_server has done.
   // Note that we leave codes beyond 127 unmodified.
   //
+  // NOTE: any updates to this table should result in an update to:
+  // tools/escape_mapper/escape_mapper.cc.
   static const unsigned char codes_to_escape[32] = {
     0xFF, 0xFF, 0xFF,
     0xFF,             // control

tools/Makefile.am

@@ -54,6 +54,14 @@ http_load_http_load_SOURCES = \
 
 endif
 
+if BUILD_TEST_TOOLS
+bin_PROGRAMS += escape_mapper/escape_mapper
+else
+noinst_PROGRAMS += escape_mapper/escape_mapper
+endif
+
+escape_mapper_escape_mapper_SOURCES = escape_mapper/escape_mapper.cc
+
 all-am: Makefile $(PROGRAMS) $(SCRIPTS) $(DATA)
 	@sed "s/ -fPIE//" tsxs > tsxs.new
 	@mv -f tsxs.new tsxs

tools/escape_mapper/README

@@ -0,0 +1,14 @@
+The `escape_mapper` tool is a simple utility that allows one to view
+the existing table used for URL escaping, found in LogUtils, specifically
+the escapify_url_common function. This function allows one to specify
+an alternate table that contains more characters to escape than the
+RFC-compliant default.
+
+WARNING: the default encoded characters list is currently hardcoded.
+
+This tool operates in two basic modes:
+  1) print out the default mappings
+  2) print out the new mapping based on the provided argument
+
+Only one argument is supported to generate a new mapping table, for example:
+	./escape_mapper '&,+/='

tools/escape_mapper/escape_mapper.cc

@@ -0,0 +1,85 @@
+/** @file
+
+  A brief file description
+
+  @section license License
+
+  Licensed to the Apache Software Foundation (ASF) under one
+  or more contributor license agreements.  See the NOTICE file
+  distributed with this work for additional information
+  regarding copyright ownership.  The ASF licenses this file
+  to you under the Apache License, Version 2.0 (the
+  "License"); you may not use this file except in compliance
+  with the License.  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+ */
+
+#include <iomanip>
+#include <iostream>
+#include <string_view>
+
+void
+add_mapping(unsigned char *table, char c)
+{
+  int i = c / 8;
+  int x = 7 - c % 8;
+  int r = 1 << x;
+
+  table[i] = table[i] | r;
+}
+
+int
+main(int argc, char *argv[])
+{
+  // only support a single arg that contains all the chars we wish to escapify
+  if (argc > 1 && argc != 2) {
+    std::cerr << "Provide a single argument with a list of characters to add to the default encoding table." << std::endl;
+    return (1);
+  }
+
+  // default characters supported by the codes_to_escape table found in LogUtils.cc
+  unsigned char to_escape[16] = {
+    ' ', '"', '#', '%', '<', '>', '[', ']', '\\', '^', '`', '{', '|', '}', '~', 0x7F,
+  };
+
+  unsigned char escape_codes[32] = {0};
+
+  // indexes 0-3 are marked as "control"
+  for (int i = 0; i < 4; i++) {
+    escape_codes[i] = 0xFF;
+  }
+
+  // add_mapping performs a logical or on the entries, so the above 0xFF values
+  // will persist.
+  for (auto char_to_escape : to_escape) {
+    add_mapping(&escape_codes[0], char_to_escape);
+  }
+
+  // add the chars specified in argv
+  if (argc > 1) {
+    std::string_view escape_characters{argv[1]};
+    for (auto const char_to_escape : escape_characters) {
+      std::cout << "Adding '" << char_to_escape << "' to escape mapping table." << std::endl;
+      add_mapping(&escape_codes[0], char_to_escape);
+    }
+    std::cout << std::endl;
+  }
+
+  std::string_view qualification{((argc > 1) ? "New" : "Default")};
+  std::cout << qualification << " Escape Mapping Table:" << std::endl;
+
+  for (unsigned long i = 0; i < sizeof(escape_codes) / sizeof(escape_codes[0]); i++) {
+    std::cout << std::dec << std::setfill(' ') << std::setw(4) << i << ": 0x";
+    auto const escape_code = static_cast<int>(escape_codes[i]);
+    std::cout << std::hex << std::uppercase << std::setfill('0') << std::setw(2) << escape_code << std::endl;
+  }
+
+  return 0;
+}