/*

 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "memory/allocation.inline.hpp"

#include "oops/oop.inline.hpp"

#include "runtime/arguments.hpp"

#include "runtime/globals.hpp"

#include "runtime/globals_extension.hpp"

#include "utilities/ostream.hpp"

#include "utilities/top.hpp"

#ifndef SERIALGC

#include "gc_implementation/g1/g1_globals.hpp"

#endif

#ifdef COMPILER1

#include "c1/c1_globals.hpp"

#endif

#ifdef COMPILER2

#include "opto/c2_globals.hpp"

#endif

#ifdef SHARK

#include "shark/shark_globals.hpp"

#endif

RUNTIME_FLAGS(MATERIALIZE_DEVELOPER_FLAG, MATERIALIZE_PD_DEVELOPER_FLAG, \

              MATERIALIZE_PRODUCT_FLAG, MATERIALIZE_PD_PRODUCT_FLAG, \

              MATERIALIZE_DIAGNOSTIC_FLAG, MATERIALIZE_EXPERIMENTAL_FLAG, \

              MATERIALIZE_NOTPRODUCT_FLAG, \

              MATERIALIZE_MANAGEABLE_FLAG, MATERIALIZE_PRODUCT_RW_FLAG, \

              MATERIALIZE_LP64_PRODUCT_FLAG)

RUNTIME_OS_FLAGS(MATERIALIZE_DEVELOPER_FLAG, MATERIALIZE_PD_DEVELOPER_FLAG, \

                 MATERIALIZE_PRODUCT_FLAG, MATERIALIZE_PD_PRODUCT_FLAG, \

                 MATERIALIZE_DIAGNOSTIC_FLAG, MATERIALIZE_NOTPRODUCT_FLAG)

MATERIALIZE_FLAGS_EXT

bool Flag::is_unlocker() const {

  return strcmp(name, "UnlockDiagnosticVMOptions") == 0     ||

         strcmp(name, "UnlockExperimentalVMOptions") == 0   ||

         is_unlocker_ext();

}

bool Flag::is_unlocked() const {

  if (strcmp(kind, "{diagnostic}") == 0) {

    if (strcmp(name, "EnableInvokeDynamic") == 0 && UnlockExperimentalVMOptions && !UnlockDiagnosticVMOptions) {

      // transitional logic to allow tests to run until they are changed

      static int warned;

      if (++warned == 1)  warning("Use -XX:+UnlockDiagnosticVMOptions before EnableInvokeDynamic flag");

      return true;

    }

    return UnlockDiagnosticVMOptions;

  } else if (strcmp(kind, "{experimental}") == 0 ||

             strcmp(kind, "{C2 experimental}") == 0) {

    return UnlockExperimentalVMOptions;

  } else {

    return is_unlocked_ext();

  }

}

bool Flag::is_writeable() const {

}

// Long term, we need to define a mechanism to specify which flags

// are external/stable and change this function accordingly.

bool Flag::is_external() const {

}

// Length of format string (e.g. "%.1234s") for printing ccstr below

#define FORMAT_BUFFER_LEN 16

void Flag::print_on(outputStream* st, bool withComments) {

  st->print("%9s %-40s %c= ", type, name, (origin != DEFAULT ? ':' : ' '));

  if (is_bool())     st->print("%-16s", get_bool() ? "true" : "false");

  if (is_intx())     st->print("%-16ld", get_intx());

  if (is_uintx())    st->print("%-16lu", get_uintx());

  if (is_uint64_t()) st->print("%-16lu", get_uint64_t());

  if (is_double())   st->print("%-16f", get_double());

  if (is_ccstr()) {

     const char* cp = get_ccstr();

     if (cp != NULL) {

       const char* eol;

       while ((eol = strchr(cp, '\n')) != NULL) {

         char format_buffer[FORMAT_BUFFER_LEN];

         size_t llen = pointer_delta(eol, cp, sizeof(char));

         jio_snprintf(format_buffer, FORMAT_BUFFER_LEN,

                     "%%." SIZE_FORMAT "s", llen);

         st->print(format_buffer, cp);

         st->cr();

         cp = eol+1;

         st->print("%5s %-35s += ", "", name);

       }

       st->print("%-16s", cp);

     }

     else st->print("%-16s", "");

  }

  st->print("%-20s", kind);

  if (withComments) {

#ifndef PRODUCT

    st->print("%s", doc );

#endif

  }

  st->cr();

}

void Flag::print_as_flag(outputStream* st) {

  if (is_bool()) {

    st->print("-XX:%s%s", get_bool() ? "+" : "-", name);

  } else if (is_intx()) {

    st->print("-XX:%s=" INTX_FORMAT, name, get_intx());

  } else if (is_uintx()) {

    st->print("-XX:%s=" UINTX_FORMAT, name, get_uintx());

  } else if (is_uint64_t()) {

    st->print("-XX:%s=" UINT64_FORMAT, name, get_uint64_t());

  } else if (is_ccstr()) {

    st->print("-XX:%s=", name);

    const char* cp = get_ccstr();

    if (cp != NULL) {

      // Need to turn embedded '\n's back into separate arguments

      // Not so efficient to print one character at a time,

      // but the choice is to do the transformation to a buffer

      // and print that.  And this need not be efficient.

      for (; *cp != '\0'; cp += 1) {

        switch (*cp) {

          default:

            st->print("%c", *cp);

            break;

          case '\n':

            st->print(" -XX:%s=", name);

            break;

        }

      }

    }

  } else {

    ShouldNotReachHere();

  }

}

// 4991491 do not "optimize out" the was_set false values: omitting them

// tickles a Microsoft compiler bug causing flagTable to be malformed

#define RUNTIME_PRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{product}", DEFAULT },

#define RUNTIME_PD_PRODUCT_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{pd product}", DEFAULT },

#define RUNTIME_DIAGNOSTIC_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{diagnostic}", DEFAULT },

#define RUNTIME_EXPERIMENTAL_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{experimental}", DEFAULT },

#define RUNTIME_MANAGEABLE_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{manageable}", DEFAULT },

#define RUNTIME_PRODUCT_RW_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{product rw}", DEFAULT },

#ifdef PRODUCT

  #define RUNTIME_DEVELOP_FLAG_STRUCT(type, name, value, doc) /* flag is constant */

  #define RUNTIME_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     /* flag is constant */

  #define RUNTIME_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc)

#else

  #define RUNTIME_DEVELOP_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "", DEFAULT },

  #define RUNTIME_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, doc, "{pd}", DEFAULT },

  #define RUNTIME_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{notproduct}", DEFAULT },

#endif

#ifdef _LP64

  #define RUNTIME_LP64_PRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{lp64_product}", DEFAULT },

#else

  #define RUNTIME_LP64_PRODUCT_FLAG_STRUCT(type, name, value, doc) /* flag is constant */

#endif // _LP64

#define C1_PRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{C1 product}", DEFAULT },

#define C1_PD_PRODUCT_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{C1 pd product}", DEFAULT },

#ifdef PRODUCT

  #define C1_DEVELOP_FLAG_STRUCT(type, name, value, doc) /* flag is constant */

  #define C1_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     /* flag is constant */

  #define C1_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc)

#else

  #define C1_DEVELOP_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{C1}", DEFAULT },

  #define C1_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, doc, "{C1 pd}", DEFAULT },

  #define C1_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{C1 notproduct}", DEFAULT },

#endif

#define C2_PRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{C2 product}", DEFAULT },

#define C2_PD_PRODUCT_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{C2 pd product}", DEFAULT },

#define C2_DIAGNOSTIC_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{C2 diagnostic}", DEFAULT },

#define C2_EXPERIMENTAL_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{C2 experimental}", DEFAULT },

#ifdef PRODUCT

  #define C2_DEVELOP_FLAG_STRUCT(type, name, value, doc) /* flag is constant */

  #define C2_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     /* flag is constant */

  #define C2_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc)

#else

  #define C2_DEVELOP_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{C2}", DEFAULT },

  #define C2_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, doc, "{C2 pd}", DEFAULT },

  #define C2_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{C2 notproduct}", DEFAULT },

#endif

#define SHARK_PRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{Shark product}", DEFAULT },

#define SHARK_PD_PRODUCT_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{Shark pd product}", DEFAULT },

#define SHARK_DIAGNOSTIC_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, NOT_PRODUCT_ARG(doc) "{Shark diagnostic}", DEFAULT },

#ifdef PRODUCT

  #define SHARK_DEVELOP_FLAG_STRUCT(type, name, value, doc) /* flag is constant */

  #define SHARK_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     /* flag is constant */

  #define SHARK_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc)

#else

  #define SHARK_DEVELOP_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{Shark}", DEFAULT },

  #define SHARK_PD_DEVELOP_FLAG_STRUCT(type, name, doc)     { #type, XSTR(name), &name, doc, "{Shark pd}", DEFAULT },

  #define SHARK_NOTPRODUCT_FLAG_STRUCT(type, name, value, doc) { #type, XSTR(name), &name, doc, "{Shark notproduct}", DEFAULT },

#endif

static Flag flagTable[] = {

 RUNTIME_FLAGS(RUNTIME_DEVELOP_FLAG_STRUCT, RUNTIME_PD_DEVELOP_FLAG_STRUCT, RUNTIME_PRODUCT_FLAG_STRUCT, RUNTIME_PD_PRODUCT_FLAG_STRUCT, RUNTIME_DIAGNOSTIC_FLAG_STRUCT, RUNTIME_EXPERIMENTAL_FLAG_STRUCT, RUNTIME_NOTPRODUCT_FLAG_STRUCT, RUNTIME_MANAGEABLE_FLAG_STRUCT, RUNTIME_PRODUCT_RW_FLAG_STRUCT, RUNTIME_LP64_PRODUCT_FLAG_STRUCT)

 RUNTIME_OS_FLAGS(RUNTIME_DEVELOP_FLAG_STRUCT, RUNTIME_PD_DEVELOP_FLAG_STRUCT, RUNTIME_PRODUCT_FLAG_STRUCT, RUNTIME_PD_PRODUCT_FLAG_STRUCT, RUNTIME_DIAGNOSTIC_FLAG_STRUCT, RUNTIME_NOTPRODUCT_FLAG_STRUCT)

#ifndef SERIALGC

 G1_FLAGS(RUNTIME_DEVELOP_FLAG_STRUCT, RUNTIME_PD_DEVELOP_FLAG_STRUCT, RUNTIME_PRODUCT_FLAG_STRUCT, RUNTIME_PD_PRODUCT_FLAG_STRUCT, RUNTIME_DIAGNOSTIC_FLAG_STRUCT, RUNTIME_EXPERIMENTAL_FLAG_STRUCT, RUNTIME_NOTPRODUCT_FLAG_STRUCT, RUNTIME_MANAGEABLE_FLAG_STRUCT, RUNTIME_PRODUCT_RW_FLAG_STRUCT)

#endif // SERIALGC

#ifdef COMPILER1

 C1_FLAGS(C1_DEVELOP_FLAG_STRUCT, C1_PD_DEVELOP_FLAG_STRUCT, C1_PRODUCT_FLAG_STRUCT, C1_PD_PRODUCT_FLAG_STRUCT, C1_NOTPRODUCT_FLAG_STRUCT)

#endif

#ifdef COMPILER2

 C2_FLAGS(C2_DEVELOP_FLAG_STRUCT, C2_PD_DEVELOP_FLAG_STRUCT, C2_PRODUCT_FLAG_STRUCT, C2_PD_PRODUCT_FLAG_STRUCT, C2_DIAGNOSTIC_FLAG_STRUCT, C2_EXPERIMENTAL_FLAG_STRUCT, C2_NOTPRODUCT_FLAG_STRUCT)

#endif

#ifdef SHARK

 SHARK_FLAGS(SHARK_DEVELOP_FLAG_STRUCT, SHARK_PD_DEVELOP_FLAG_STRUCT, SHARK_PRODUCT_FLAG_STRUCT, SHARK_PD_PRODUCT_FLAG_STRUCT, SHARK_DIAGNOSTIC_FLAG_STRUCT, SHARK_NOTPRODUCT_FLAG_STRUCT)

#endif

 FLAGTABLE_EXT

 {0, NULL, NULL}

};

Flag* Flag::flags = flagTable;

size_t Flag::numFlags = (sizeof(flagTable) / sizeof(Flag));

inline bool str_equal(const char* s, char* q, size_t len) {

  // s is null terminated, q is not!

  if (strlen(s) != (unsigned int) len) return false;

  return strncmp(s, q, len) == 0;

}

Flag* Flag::find_flag(char* name, size_t length) {

  for (Flag* current = &flagTable[0]; current->name; current++) {

    if (str_equal(current->name, name, length)) {

      if (!(current->is_unlocked() || current->is_unlocker())) {

        // disable use of diagnostic or experimental flags until they

        // are explicitly unlocked

        return NULL;

      }

      return current;

    }

  }

  return NULL;

}

// Returns the address of the index'th element

static Flag* address_of_flag(CommandLineFlagWithType flag) {

  assert((size_t)flag < Flag::numFlags, "bad command line flag index");

  return &Flag::flags[flag];

}

bool CommandLineFlagsEx::is_default(CommandLineFlag flag) {

  assert((size_t)flag < Flag::numFlags, "bad command line flag index");

  Flag* f = &Flag::flags[flag];

  return (f->origin == DEFAULT);

}

bool CommandLineFlagsEx::is_ergo(CommandLineFlag flag) {

  assert((size_t)flag < Flag::numFlags, "bad command line flag index");

  Flag* f = &Flag::flags[flag];

  return (f->origin == ERGONOMIC);

}

bool CommandLineFlagsEx::is_cmdline(CommandLineFlag flag) {

  assert((size_t)flag < Flag::numFlags, "bad command line flag index");

  Flag* f = &Flag::flags[flag];

  return (f->origin == COMMAND_LINE);

}

bool CommandLineFlags::wasSetOnCmdline(const char* name, bool* value) {

  Flag* result = Flag::find_flag((char*)name, strlen(name));

  if (result == NULL) return false;

  *value = (result->origin == COMMAND_LINE);

  return true;

}

bool CommandLineFlags::boolAt(char* name, size_t len, bool* value) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_bool()) return false;

  *value = result->get_bool();

  return true;

}

bool CommandLineFlags::boolAtPut(char* name, size_t len, bool* value, FlagValueOrigin origin) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_bool()) return false;

  bool old_value = result->get_bool();

  result->set_bool(*value);

  *value = old_value;

  result->origin = origin;

  return true;

}

void CommandLineFlagsEx::boolAtPut(CommandLineFlagWithType flag, bool value, FlagValueOrigin origin) {

  Flag* faddr = address_of_flag(flag);

  guarantee(faddr != NULL && faddr->is_bool(), "wrong flag type");

  faddr->set_bool(value);

  faddr->origin = origin;

}

bool CommandLineFlags::intxAt(char* name, size_t len, intx* value) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_intx()) return false;

  *value = result->get_intx();

  return true;

}

bool CommandLineFlags::intxAtPut(char* name, size_t len, intx* value, FlagValueOrigin origin) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_intx()) return false;

  intx old_value = result->get_intx();

  result->set_intx(*value);

  *value = old_value;

  result->origin = origin;

  return true;

}

void CommandLineFlagsEx::intxAtPut(CommandLineFlagWithType flag, intx value, FlagValueOrigin origin) {

  Flag* faddr = address_of_flag(flag);

  guarantee(faddr != NULL && faddr->is_intx(), "wrong flag type");

  faddr->set_intx(value);

  faddr->origin = origin;

}

bool CommandLineFlags::uintxAt(char* name, size_t len, uintx* value) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_uintx()) return false;

  *value = result->get_uintx();

  return true;

}

bool CommandLineFlags::uintxAtPut(char* name, size_t len, uintx* value, FlagValueOrigin origin) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_uintx()) return false;

  uintx old_value = result->get_uintx();

  result->set_uintx(*value);

  *value = old_value;

  result->origin = origin;

  return true;

}

void CommandLineFlagsEx::uintxAtPut(CommandLineFlagWithType flag, uintx value, FlagValueOrigin origin) {

  Flag* faddr = address_of_flag(flag);

  guarantee(faddr != NULL && faddr->is_uintx(), "wrong flag type");

  faddr->set_uintx(value);

  faddr->origin = origin;

}

bool CommandLineFlags::uint64_tAt(char* name, size_t len, uint64_t* value) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_uint64_t()) return false;

  *value = result->get_uint64_t();

  return true;

}

bool CommandLineFlags::uint64_tAtPut(char* name, size_t len, uint64_t* value, FlagValueOrigin origin) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_uint64_t()) return false;

  uint64_t old_value = result->get_uint64_t();

  result->set_uint64_t(*value);

  *value = old_value;

  result->origin = origin;

  return true;

}

void CommandLineFlagsEx::uint64_tAtPut(CommandLineFlagWithType flag, uint64_t value, FlagValueOrigin origin) {

  Flag* faddr = address_of_flag(flag);

  guarantee(faddr != NULL && faddr->is_uint64_t(), "wrong flag type");

  faddr->set_uint64_t(value);

  faddr->origin = origin;

}

bool CommandLineFlags::doubleAt(char* name, size_t len, double* value) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_double()) return false;

  *value = result->get_double();

  return true;

}

bool CommandLineFlags::doubleAtPut(char* name, size_t len, double* value, FlagValueOrigin origin) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_double()) return false;

  double old_value = result->get_double();

  result->set_double(*value);

  *value = old_value;

  result->origin = origin;

  return true;

}

void CommandLineFlagsEx::doubleAtPut(CommandLineFlagWithType flag, double value, FlagValueOrigin origin) {

  Flag* faddr = address_of_flag(flag);

  guarantee(faddr != NULL && faddr->is_double(), "wrong flag type");

  faddr->set_double(value);

  faddr->origin = origin;

}

bool CommandLineFlags::ccstrAt(char* name, size_t len, ccstr* value) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_ccstr()) return false;

  *value = result->get_ccstr();

  return true;

}

// Contract:  Flag will make private copy of the incoming value.

// Outgoing value is always malloc-ed, and caller MUST call free.

bool CommandLineFlags::ccstrAtPut(char* name, size_t len, ccstr* value, FlagValueOrigin origin) {

  Flag* result = Flag::find_flag(name, len);

  if (result == NULL) return false;

  if (!result->is_ccstr()) return false;

  ccstr old_value = result->get_ccstr();

  char* new_value = NULL;

  if (*value != NULL) {

    new_value = NEW_C_HEAP_ARRAY(char, strlen(*value)+1);

    strcpy(new_value, *value);

  }

  result->set_ccstr(new_value);

  if (result->origin == DEFAULT && old_value != NULL) {

    // Prior value is NOT heap allocated, but was a literal constant.

    char* old_value_to_free = NEW_C_HEAP_ARRAY(char, strlen(old_value)+1);

    strcpy(old_value_to_free, old_value);

    old_value = old_value_to_free;

  }

  *value = old_value;

  result->origin = origin;

  return true;

}

// Contract:  Flag will make private copy of the incoming value.

void CommandLineFlagsEx::ccstrAtPut(CommandLineFlagWithType flag, ccstr value, FlagValueOrigin origin) {

  Flag* faddr = address_of_flag(flag);

  guarantee(faddr != NULL && faddr->is_ccstr(), "wrong flag type");

  ccstr old_value = faddr->get_ccstr();

  char* new_value = NEW_C_HEAP_ARRAY(char, strlen(value)+1);

  strcpy(new_value, value);

  faddr->set_ccstr(new_value);

  if (faddr->origin != DEFAULT && old_value != NULL) {

    // Prior value is heap allocated so free it.

    FREE_C_HEAP_ARRAY(char, old_value);

  }

  faddr->origin = origin;

}

extern "C" {

  static int compare_flags(const void* void_a, const void* void_b) {

    return strcmp((*((Flag**) void_a))->name, (*((Flag**) void_b))->name);

  }

}

void CommandLineFlags::printSetFlags() {

  // Print which flags were set on the command line

  // note: this method is called before the thread structure is in place

  //       which means resource allocation cannot be used.

  // Compute size

  int length= 0;

  while (flagTable[length].name != NULL) length++;

  // Sort

  Flag** array = NEW_C_HEAP_ARRAY(Flag*, length);

  for (int index = 0; index < length; index++) {

    array[index] = &flagTable[index];

  }

  qsort(array, length, sizeof(Flag*), compare_flags);

  // Print

  for (int i = 0; i < length; i++) {

    if (array[i]->origin /* naked field! */) {

      array[i]->print_as_flag(tty);