1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaClasses.hpp"
  27 #include "runtime/arguments.hpp"
  28 #include "runtime/commandLineFlagRangeList.hpp"
  29 #include "runtime/java.hpp"
  30 #include "runtime/jniHandles.hpp"
  31 #include "runtime/sharedRuntime.hpp"
  32 #include "services/writeableFlags.hpp"
  33 
  34 #define TEMP_BUF_SIZE 256
  35 
  36 static void print_flag_error_message_bounds(const char* name, char* buffer) {
  37   CommandLineFlagRange* range = CommandLineFlagRangeList::find(name);
  38   if (range != NULL) {
  39     os::strlcat(buffer, "must have value in range ", TEMP_BUF_SIZE);
  40 
  41     stringStream stream;
  42     range->print(&stream);
  43     char* range_string = stream.as_string();
  44     char range_string_no_whitespaces[TEMP_BUF_SIZE];
  45     int j = 0;
  46     for (int i=0; i<TEMP_BUF_SIZE-1; i++) {
  47       if (range_string[i] == '\0') {
  48         break;
  49       } else if (range_string[i] != ' ') {
  50         range_string_no_whitespaces[j] = range_string[i];
  51         j++;
  52       }
  53     }
  54     range_string_no_whitespaces[j] = '\0';
  55 
  56     os::strlcat(buffer, range_string_no_whitespaces, TEMP_BUF_SIZE);
  57   }
  58 }
  59 
  60 PRAGMA_FORMAT_NONLITERAL_IGNORED_EXTERNAL
  61 static void print_flag_error_message_if_needed(Flag::Error error, const char* name, FormatBuffer<80>& err_msg) {
  62   if (error != Flag::SUCCESS) {
  63     char buffer[TEMP_BUF_SIZE] = {'\0'};
  64     if ((error != Flag::MISSING_NAME) && (name != NULL)) {
  65       os::strlcat(buffer, name, TEMP_BUF_SIZE);
  66       os::strlcat(buffer, " error: ", TEMP_BUF_SIZE);
  67     } else {
  68       os::strlcat(buffer, "Error: ", TEMP_BUF_SIZE);
  69     }
  70     switch (error) {
  71       case Flag::MISSING_NAME:
  72         os::strlcat(buffer, "flag name is missing.", TEMP_BUF_SIZE); break;
  73       case Flag::MISSING_VALUE:
  74         os::strlcat(buffer, "parsing the textual form of the value.", TEMP_BUF_SIZE); break;
  75       case Flag::NON_WRITABLE:
  76         os::strlcat(buffer, "flag is not writeable.", TEMP_BUF_SIZE); break;
  77       case Flag::OUT_OF_BOUNDS:
  78         print_flag_error_message_bounds(name, buffer); break;
  79       case Flag::VIOLATES_CONSTRAINT:
  80         os::strlcat(buffer, "value violates its flag's constraint.", TEMP_BUF_SIZE); break;
  81       case Flag::INVALID_FLAG:
  82         os::strlcat(buffer, "there is no flag with the given name.", TEMP_BUF_SIZE); break;
  83       case Flag::ERR_OTHER:
  84         os::strlcat(buffer, "other, unspecified error related to setting the flag.", TEMP_BUF_SIZE); break;
  85       case Flag::SUCCESS:
  86         break;
  87     }
  88     buffer[79] = '\0';
  89     PRAGMA_DIAG_PUSH
  90     PRAGMA_FORMAT_NONLITERAL_IGNORED_INTERNAL
  91     err_msg.print(buffer);
  92     PRAGMA_DIAG_POP
  93   }
  94 }
  95 
  96 // set a boolean global flag
  97 Flag::Error WriteableFlags::set_bool_flag(const char* name, const char* arg, Flag::Flags origin, FormatBuffer<80>& err_msg) {
  98   int value = true;
  99 
 100   if (sscanf(arg, "%d", &value)) {
 101     return set_bool_flag(name, value != 0, origin, err_msg);
 102   }
 103   err_msg.print("flag value must be a boolean (1 or 0)");
 104   return Flag::WRONG_FORMAT;
 105 }
 106 
 107 Flag::Error WriteableFlags::set_bool_flag(const char* name, bool value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 108   Flag::Error err = CommandLineFlags::boolAtPut((char*)name, &value, origin);
 109   print_flag_error_message_if_needed(err, name, err_msg);
 110   return err;
 111 }
 112 
 113 // set a intx global flag
 114 Flag::Error WriteableFlags::set_intx_flag(const char* name, const char* arg, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 115   intx value;
 116 
 117   if (sscanf(arg, INTX_FORMAT, &value)) {
 118     return set_intx_flag(name, value, origin, err_msg);
 119   }
 120   err_msg.print("flag value must be an integer");
 121   return Flag::WRONG_FORMAT;
 122 }
 123 
 124 Flag::Error WriteableFlags::set_intx_flag(const char* name, intx value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 125   Flag::Error err = CommandLineFlags::intxAtPut((char*)name, &value, origin);
 126   print_flag_error_message_if_needed(err, name, err_msg);
 127   return err;
 128 }
 129 
 130 // set a uintx global flag
 131 Flag::Error WriteableFlags::set_uintx_flag(const char* name, const char* arg, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 132   uintx value;
 133 
 134   if (sscanf(arg, UINTX_FORMAT, &value)) {
 135     return set_uintx_flag(name, value, origin, err_msg);
 136   }
 137   err_msg.print("flag value must be an unsigned integer");
 138   return Flag::WRONG_FORMAT;
 139 }
 140 
 141 Flag::Error WriteableFlags::set_uintx_flag(const char* name, uintx value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 142   Flag::Error err = CommandLineFlags::uintxAtPut((char*)name, &value, origin);
 143   print_flag_error_message_if_needed(err, name, err_msg);
 144   return err;
 145 }
 146 
 147 // set a uint64_t global flag
 148 Flag::Error WriteableFlags::set_uint64_t_flag(const char* name, const char* arg, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 149   uint64_t value;
 150 
 151   if (sscanf(arg, UINT64_FORMAT, &value)) {
 152     return set_uint64_t_flag(name, value, origin, err_msg);
 153   }
 154   err_msg.print("flag value must be an unsigned 64-bit integer");
 155   return Flag::WRONG_FORMAT;
 156 }
 157 
 158 Flag::Error WriteableFlags::set_uint64_t_flag(const char* name, uint64_t value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 159   Flag::Error err = CommandLineFlags::uint64_tAtPut((char*)name, &value, origin);
 160   print_flag_error_message_if_needed(err, name, err_msg);
 161   return err;
 162 }
 163 
 164 // set a size_t global flag
 165 Flag::Error WriteableFlags::set_size_t_flag(const char* name, const char* arg, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 166   size_t value;
 167 
 168   if (sscanf(arg, SIZE_FORMAT, &value)) {
 169     return set_size_t_flag(name, value, origin, err_msg);
 170   }
 171   err_msg.print("flag value must be an unsigned integer");
 172   return Flag::WRONG_FORMAT;
 173 }
 174 
 175 Flag::Error WriteableFlags::set_size_t_flag(const char* name, size_t value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 176   Flag::Error err = CommandLineFlags::size_tAtPut((char*)name, &value, origin);
 177   print_flag_error_message_if_needed(err, name, err_msg);
 178   return err;
 179 }
 180 
 181 // set a string global flag using value from AttachOperation
 182 Flag::Error WriteableFlags::set_ccstr_flag(const char* name, const char* value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 183   Flag::Error err = CommandLineFlags::ccstrAtPut((char*)name, &value, origin);
 184   print_flag_error_message_if_needed(err, name, err_msg);
 185   return err;
 186 }
 187 
 188 /* sets a writeable flag to the provided value
 189  *
 190  * - return status is one of the WriteableFlags::err enum values
 191  * - an eventual error message will be generated to the provided err_msg buffer
 192  */
 193 Flag::Error WriteableFlags::set_flag(const char* flag_name, const char* flag_value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 194   return set_flag(flag_name, &flag_value, set_flag_from_char, origin, err_msg);
 195 }
 196 
 197 /* sets a writeable flag to the provided value
 198  *
 199  * - return status is one of the WriteableFlags::err enum values
 200  * - an eventual error message will be generated to the provided err_msg buffer
 201  */
 202 Flag::Error WriteableFlags::set_flag(const char* flag_name, jvalue flag_value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 203   return set_flag(flag_name, &flag_value, set_flag_from_jvalue, origin, err_msg);
 204 }
 205 
 206 // a writeable flag setter accepting either 'jvalue' or 'char *' values
 207 Flag::Error WriteableFlags::set_flag(const char* name, const void* value, Flag::Error(*setter)(Flag*,const void*,Flag::Flags,FormatBuffer<80>&), Flag::Flags origin, FormatBuffer<80>& err_msg) {
 208   if (name == NULL) {
 209     err_msg.print("flag name is missing");
 210     return Flag::MISSING_NAME;
 211   }
 212   if (value == NULL) {
 213     err_msg.print("flag value is missing");
 214     return Flag::MISSING_VALUE;
 215   }
 216 
 217   Flag* f = Flag::find_flag((char*)name, strlen(name));
 218   if (f) {
 219     // only writeable flags are allowed to be set
 220     if (f->is_writeable()) {
 221       return setter(f, value, origin, err_msg);
 222     } else {
 223       err_msg.print("only 'writeable' flags can be set");
 224       return Flag::NON_WRITABLE;
 225     }
 226   }
 227 
 228   err_msg.print("flag %s does not exist", name);
 229   return Flag::INVALID_FLAG;
 230 }
 231 
 232 // a writeable flag setter accepting 'char *' values
 233 Flag::Error WriteableFlags::set_flag_from_char(Flag* f, const void* value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 234   char* flag_value = *(char**)value;
 235   if (flag_value == NULL) {
 236     err_msg.print("flag value is missing");
 237     return Flag::MISSING_VALUE;
 238   }
 239   if (f->is_bool()) {
 240     return set_bool_flag(f->_name, flag_value, origin, err_msg);
 241   } else if (f->is_intx()) {
 242     return set_intx_flag(f->_name, flag_value, origin, err_msg);
 243   } else if (f->is_uintx()) {
 244     return set_uintx_flag(f->_name, flag_value, origin, err_msg);
 245   } else if (f->is_uint64_t()) {
 246     return set_uint64_t_flag(f->_name, flag_value, origin, err_msg);
 247   } else if (f->is_size_t()) {
 248     return set_size_t_flag(f->_name, flag_value, origin, err_msg);
 249   } else if (f->is_ccstr()) {
 250     return set_ccstr_flag(f->_name, flag_value, origin, err_msg);
 251   } else {
 252     ShouldNotReachHere();
 253   }
 254   return Flag::ERR_OTHER;
 255 }
 256 
 257 // a writeable flag setter accepting 'jvalue' values
 258 Flag::Error WriteableFlags::set_flag_from_jvalue(Flag* f, const void* value, Flag::Flags origin, FormatBuffer<80>& err_msg) {
 259   jvalue new_value = *(jvalue*)value;
 260   if (f->is_bool()) {
 261     bool bvalue = (new_value.z == JNI_TRUE ? true : false);
 262     return set_bool_flag(f->_name, bvalue, origin, err_msg);
 263   } else if (f->is_intx()) {
 264     intx ivalue = (intx)new_value.j;
 265     return set_intx_flag(f->_name, ivalue, origin, err_msg);
 266   } else if (f->is_uintx()) {
 267     uintx uvalue = (uintx)new_value.j;
 268     return set_uintx_flag(f->_name, uvalue, origin, err_msg);
 269   } else if (f->is_uint64_t()) {
 270     uint64_t uvalue = (uint64_t)new_value.j;
 271     return set_uint64_t_flag(f->_name, uvalue, origin, err_msg);
 272   } else if (f->is_size_t()) {
 273     size_t svalue = (size_t)new_value.j;
 274     return set_size_t_flag(f->_name, svalue, origin, err_msg);
 275   } else if (f->is_ccstr()) {
 276     oop str = JNIHandles::resolve_external_guard(new_value.l);
 277     if (str == NULL) {
 278       err_msg.print("flag value is missing");
 279       return Flag::MISSING_VALUE;
 280     }
 281     ccstr svalue = java_lang_String::as_utf8_string(str);
 282     Flag::Error ret = WriteableFlags::set_ccstr_flag(f->_name, svalue, origin, err_msg);
 283     if (ret != Flag::SUCCESS) {
 284       FREE_C_HEAP_ARRAY(char, svalue);
 285     }
 286     return ret;
 287   } else {
 288     ShouldNotReachHere();
 289   }
 290   return Flag::ERR_OTHER;
 291 }
 292