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 // Copyright (c) 2011 Google Inc.

 // All rights reserved.

 //

 // Redistribution and use in source and binary forms, with or without

 // modification, are permitted provided that the following conditions are

 // met:

 //

 //     * Redistributions of source code must retain the above copyright

 // notice, this list of conditions and the following disclaimer.

 //     * Redistributions in binary form must reproduce the above

 // copyright notice, this list of conditions and the following disclaimer

 // in the documentation and/or other materials provided with the

 // distribution.

 //     * Neither the name of Google Inc. nor the names of its

 // contributors may be used to endorse or promote products derived from

 // this software without specific prior written permission.

 //

 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 // Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>

 // module.cc: Implement google_breakpad::Module.  See module.h.

 #include "common/module.h"

 #include <assert.h>

 #include <errno.h>

 #include <stdio.h>

 #include <string.h>

 #include <algorithm>

 #include <iostream>

 #include <utility>

 namespace google_breakpad {

 using std::dec;

 using std::endl;

 using std::hex;

 Module::Module(const string &name, const string &os,

                const string &architecture, const string &id) :

     name_(name),

     os_(os),

     architecture_(architecture),

     id_(id),

     load_address_(0) { }

 Module::~Module() {

   for (FileByNameMap::iterator it = files_.begin(); it != files_.end(); ++it)

     delete it->second;

   for (FunctionSet::iterator it = functions_.begin();

        it != functions_.end(); ++it) {

     delete *it;

   }

   for (StackFrameEntrySet::iterator it = stack_frame_entries_.begin();

        it != stack_frame_entries_.end(); ++it) {

     delete *it;

   }

   for (ExternSet::iterator it = externs_.begin(); it != externs_.end(); ++it)

     delete *it;

 }

 void Module::SetLoadAddress(Address address) {

   load_address_ = address;

 }

 void Module::AddFunction(Function *function) {

   // FUNC lines must not hold an empty name, so catch the problem early if

   // callers try to add one.

   assert(!function->name.empty());

   std::pair<FunctionSet::iterator,bool> ret = functions_.insert(function);

   if (!ret.second) {

     // Free the duplicate that was not inserted because this Module

     // now owns it.

     delete function;

   }

 }

 void Module::AddFunctions(vector<Function *>::iterator begin,

                           vector<Function *>::iterator end) {

   for (vector<Function *>::iterator it = begin; it != end; ++it)

     AddFunction(*it);

 }

 void Module::AddStackFrameEntry(StackFrameEntry* stack_frame_entry) {

   std::pair<StackFrameEntrySet::iterator,bool> ret =

       stack_frame_entries_.insert(stack_frame_entry);

   if (!ret.second) {

     // Free the duplicate that was not inserted because this Module

     // now owns it.

     delete stack_frame_entry;

   }

 }

 void Module::AddExtern(Extern *ext) {

   std::pair<ExternSet::iterator,bool> ret = externs_.insert(ext);

   if (!ret.second) {

     // Free the duplicate that was not inserted because this Module

     // now owns it.

     delete ext;

   }

 }

 void Module::GetFunctions(vector<Function *> *vec,

                           vector<Function *>::iterator i) {

   vec->insert(i, functions_.begin(), functions_.end());

 }

 template<typename T>

 bool EntryContainsAddress(T entry, Module::Address address) {

   return entry->address <= address && address < entry->address + entry->size;

 }

 Module::Function* Module::FindFunctionByAddress(Address address) {

   Function search;

   search.address = address;

   // Ensure that name always sorts higher than the function name,

   // so that upper_bound always returns the function just after

   // the function containing this address.

   search.name = "\xFF";

   FunctionSet::iterator it = functions_.upper_bound(&search);

   if (it == functions_.begin())

     return NULL;

   it--;

   if (EntryContainsAddress(*it, address))

     return *it;

   return NULL;

 }

 void Module::GetExterns(vector<Extern *> *vec,

                         vector<Extern *>::iterator i) {

   vec->insert(i, externs_.begin(), externs_.end());

 }

 Module::Extern* Module::FindExternByAddress(Address address) {

   Extern search;

   search.address = address;

   ExternSet::iterator it = externs_.upper_bound(&search);

   if (it == externs_.begin())

     return NULL;

   it--;

   if ((*it)->address > address)

     return NULL;

   return *it;

 }

 Module::File *Module::FindFile(const string &name) {

   // A tricky bit here.  The key of each map entry needs to be a

   // pointer to the entry's File's name string.  This means that we

   // can't do the initial lookup with any operation that would create

   // an empty entry for us if the name isn't found (like, say,

   // operator[] or insert do), because such a created entry's key will

   // be a pointer the string passed as our argument.  Since the key of

   // a map's value type is const, we can't fix it up once we've

   // created our file.  lower_bound does the lookup without doing an

   // insertion, and returns a good hint iterator to pass to insert.

   // Our "destiny" is where we belong, whether we're there or not now.

   FileByNameMap::iterator destiny = files_.lower_bound(&name);

   if (destiny == files_.end()

       || *destiny->first != name) {  // Repeated string comparison, boo hoo.

     File *file = new File;

     file->name = name;

     file->source_id = -1;

     destiny = files_.insert(destiny,

                             FileByNameMap::value_type(&file->name, file));

   }

   return destiny->second;

 }

 Module::File *Module::FindFile(const char *name) {

   string name_string = name;

   return FindFile(name_string);

 }

 Module::File *Module::FindExistingFile(const string &name) {

   FileByNameMap::iterator it = files_.find(&name);

   return (it == files_.end()) ? NULL : it->second;

 }

 void Module::GetFiles(vector<File *> *vec) {

   vec->clear();

   for (FileByNameMap::iterator it = files_.begin(); it != files_.end(); ++it)

     vec->push_back(it->second);

 }

 void Module::GetStackFrameEntries(vector<StackFrameEntry *>* vec) {

   vec->clear();

   vec->insert(vec->begin(), stack_frame_entries_.begin(),

               stack_frame_entries_.end());

 }

 Module::StackFrameEntry* Module::FindStackFrameEntryByAddress(Address address) {

   StackFrameEntry search;

   search.address = address;

   StackFrameEntrySet::iterator it = stack_frame_entries_.upper_bound(&search);

   if (it == stack_frame_entries_.begin())

     return NULL;

   it--;

   if (EntryContainsAddress(*it, address))

     return *it;

   return NULL;

 }

 void Module::AssignSourceIds() {

   // First, give every source file an id of -1.

   for (FileByNameMap::iterator file_it = files_.begin();

        file_it != files_.end(); ++file_it) {

     file_it->second->source_id = -1;

   }

   // Next, mark all files actually cited by our functions' line number

   // info, by setting each one's source id to zero.

   for (FunctionSet::const_iterator func_it = functions_.begin();

        func_it != functions_.end(); ++func_it) {

     Function *func = *func_it;

     for (vector<Line>::iterator line_it = func->lines.begin();

          line_it != func->lines.end(); ++line_it)

       line_it->file->source_id = 0;

   }

   // Finally, assign source ids to those files that have been marked.

   // We could have just assigned source id numbers while traversing

   // the line numbers, but doing it this way numbers the files in

   // lexicographical order by name, which is neat.

   int next_source_id = 0;

   for (FileByNameMap::iterator file_it = files_.begin();

        file_it != files_.end(); ++file_it) {

     if (!file_it->second->source_id)

       file_it->second->source_id = next_source_id++;

   }

 }

 bool Module::ReportError() {

   fprintf(stderr, "error writing symbol file: %s\n",

           strerror(errno));

   return false;

 }

 std::ostream& operator<<(std::ostream& stream, const Module::Expr& expr) {

   assert(!expr.isExprInvalid());

   switch (expr.how_) {

     case Module::kExprSimple:

       stream << FromUniqueString(expr.ident_) << " " << expr.offset_ << " +";

       break;

     case Module::kExprSimpleMem:

       stream << FromUniqueString(expr.ident_) << " " << expr.offset_ << " + ^";

       break;

     case Module::kExprPostfix:

       stream << expr.postfix_; break;

     case Module::kExprInvalid:

     default:

       break;

   }

   return stream;

 }

 bool Module::WriteRuleMap(const RuleMap &rule_map, std::ostream &stream) {

   // Visit the register rules in alphabetical order.  Because

   // rule_map has the elements in some arbitrary order,

   // get the names out into a vector, sort them, and visit in

   // sorted order.

   std::vector<const UniqueString*> rr_names;

   for (RuleMap::const_iterator it = rule_map.begin();

        it != rule_map.end(); ++it) {

     rr_names.push_back(it->first);

   }

   std::sort(rr_names.begin(), rr_names.end(), LessThan_UniqueString);

   // Now visit the register rules in alphabetical order.

   for (std::vector<const UniqueString*>::const_iterator name = rr_names.begin();

        name != rr_names.end();

        ++name) {

     if (name != rr_names.begin())

       stream << " ";

     stream << FromUniqueString(*name) << ": " << rule_map.find(*name)->second;

   }

   return stream.good();

 }

 bool Module::Write(std::ostream &stream, SymbolData symbol_data) {

   stream << "MODULE " << os_ << " " << architecture_ << " "

          << id_ << " " << name_ << endl;

   if (!stream.good())

     return ReportError();

   if (symbol_data != ONLY_CFI) {

     AssignSourceIds();

     // Write out files.

     for (FileByNameMap::iterator file_it = files_.begin();

          file_it != files_.end(); ++file_it) {

       File *file = file_it->second;

       if (file->source_id >= 0) {

         stream << "FILE " << file->source_id << " " <<  file->name << endl;

         if (!stream.good())

           return ReportError();

       }

     }

     // Write out functions and their lines.

     for (FunctionSet::const_iterator func_it = functions_.begin();

          func_it != functions_.end(); ++func_it) {

       Function *func = *func_it;

       stream << "FUNC " << hex

              << (func->address - load_address_) << " "

              << func->size << " "

              << func->parameter_size << " "

              << func->name << dec << endl;

       if (!stream.good())

         return ReportError();

       for (vector<Line>::iterator line_it = func->lines.begin();

            line_it != func->lines.end(); ++line_it) {

         stream << hex

                << (line_it->address - load_address_) << " "

                << line_it->size << " "

                << dec

                << line_it->number << " "

                << line_it->file->source_id << endl;

         if (!stream.good())

           return ReportError();

       }

     }

     // Write out 'PUBLIC' records.

     for (ExternSet::const_iterator extern_it = externs_.begin();

          extern_it != externs_.end(); ++extern_it) {

       Extern *ext = *extern_it;

       stream << "PUBLIC " << hex

              << (ext->address - load_address_) << " 0 "

              << ext->name << dec << endl;

     }

   }

   if (symbol_data != NO_CFI) {

     // Write out 'STACK CFI INIT' and 'STACK CFI' records.

     StackFrameEntrySet::const_iterator frame_it;

     for (frame_it = stack_frame_entries_.begin();

          frame_it != stack_frame_entries_.end(); ++frame_it) {

       StackFrameEntry *entry = *frame_it;

       stream << "STACK CFI INIT " << hex

              << (entry->address - load_address_) << " "

              << entry->size << " " << dec;

       if (!stream.good()

           || !WriteRuleMap(entry->initial_rules, stream))

         return ReportError();

       stream << endl;

       // Write out this entry's delta rules as 'STACK CFI' records.

       for (RuleChangeMap::const_iterator delta_it = entry->rule_changes.begin();

            delta_it != entry->rule_changes.end(); ++delta_it) {

         stream << "STACK CFI " << hex

                << (delta_it->first - load_address_) << " " << dec;

         if (!stream.good()

             || !WriteRuleMap(delta_it->second, stream))

           return ReportError();

         stream << endl;

       }

     }

   }

   return true;

 }

 }  // namespace google_breakpad