source/gldbg.cpp

   1 #include <algorithm>
   2 #include <stdexcept>
   3 #include <cstdlib>
   4 #include <climits>
   5 #include <fcntl.h>
   6 #include <signal.h>
   7 #include <unistd.h>
   8 #include <sys/poll.h>
   9 #include <sys/socket.h>
  10 #include <readline/readline.h>
  11 #include "functions.h"
  12 #include "gldbg.h"
  13 #include "gldecoder.h"
  14 #include "packet.h"
  15 #include "strformat.h"
  16 #include "tool.h"
  17
  18 using namespace std;
  19
  20 GlDbg *GlDbg::instance = 0;
  21
  22 GlDbg::GlDbg(int argc, char **argv):
  23         done(false),
  24         cmd_interp(*this),
  25         process(vector<string>(argv+1, argv+argc)),
  26         sock_fd(-1),
  27         buf_offset(0),
  28         flushing(false),
  29         got_sigchld(false),
  30         stop_reason(0),
  31         current_break(0)
  32 {
  33         instance = this;
  34
  35         char buf[PATH_MAX];
  36         unsigned len = readlink("/proc/self/exe", buf, sizeof(buf));
  37         string exe(buf, len);
  38         string::size_type slash = exe.rfind('/');
  39         process.setenv("LD_PRELOAD", (exe.substr(0, slash+1)+"glwrap.so"));
  40
  41         const list<Tool::Factory *> &factories = Tool::get_factories();
  42         for(list<Tool::Factory *>::const_iterator i=factories.begin(); i!=factories.end(); ++i)
  43                 tools.push_back((*i)->create(*this));
  44 }
  45
  46 GlDbg::~GlDbg()
  47 {
  48         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  49                 delete *i;
  50 }
  51
  52 int GlDbg::main()
  53 {
  54         signal(SIGINT, &sighandler);
  55         signal(SIGCHLD, &sighandler);
  56
  57         printf("GLdbg 0.0\n");
  58         printf("Copyright © 2009-2010 Mikkosoft Productions\n");
  59         printf("Type \"help\" for a list of commands\n");
  60
  61         while(!done)
  62                 tick();
  63
  64         return 0;
  65 }
  66
  67 void GlDbg::launch()
  68 {
  69         if(process.get_state()!=Process::INACTIVE)
  70                 throw runtime_error("Program is already running");
  71
  72         int fds[2];
  73         socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
  74         sock_fd = fds[0];
  75
  76         int flags = fcntl(sock_fd, F_GETFD);
  77         fcntl(sock_fd, F_SETFD, flags|FD_CLOEXEC);
  78
  79         process.setenv("GLWRAP_FD", strformat("%d", fds[1]));
  80         process.setenv("GLWRAP_CTRL_FD", strformat("%d", fds[1]));
  81         process.launch();
  82         close(fds[1]);
  83
  84         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); )
  85         {
  86                 if(i->has_owner(0))
  87                 {
  88                         i->owners.clear();
  89                         i->owners.push_back(0);
  90                         send_breakpoint(i->function, i->flag, 0);
  91                         ++i;
  92                 }
  93                 else
  94                         breakpoints.erase(i++);
  95         }
  96
  97         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  98                 (*i)->process_started();
  99 }
 100
 101 void GlDbg::send(GlPacket *pkt)
 102 {
 103         if(process.get_state()==Process::INACTIVE)
 104                 throw runtime_error("Program is not running");
 105
 106         packet_send(pkt, sock_fd);
 107 }
 108
 109 void GlDbg::hold()
 110 {
 111         GlPacket *pkt = packet_begin(FUNC_GLDHOLD);
 112         send(pkt);
 113 }
 114
 115 void GlDbg::send_breakpoint(unsigned short func, unsigned char set_flags, unsigned char clear_flags)
 116 {
 117         GlPacket *pkt = packet_begin(FUNC_GLDBREAK);
 118         packet_write_short(pkt, func);
 119         packet_write_char(pkt, set_flags);
 120         packet_write_char(pkt, clear_flags);
 121         send(pkt);
 122 }
 123
 124 void GlDbg::set_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 125 {
 126         Breakpoint *bp = (func ? get_breakpoint(func, flag) : 0);
 127         if(bp)
 128                 bp->add_owner(owner);
 129         else
 130         {
 131                 if(func)
 132                 {
 133                         breakpoints.push_back(Breakpoint(func, flag));
 134                         breakpoints.back().add_owner(owner);
 135                 }
 136
 137                 if(process.get_state()>=Process::RUNNING)
 138                         send_breakpoint(func, flag, 0);
 139         }
 140 }
 141
 142 void GlDbg::clear_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 143 {
 144         Breakpoint *bp = get_breakpoint(func, flag);
 145         if(bp)
 146         {
 147                 bp->remove_owner(owner);
 148                 if(bp->owners.empty())
 149                 {
 150                         if(current_break==bp)
 151                                 current_break = 0;
 152
 153                         // XXX Inefficient.  Should get_breakpoint() return an iterator?
 154                         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 155                                 if(i->function==func && i->flag==flag)
 156                                 {
 157                                         breakpoints.erase(i);
 158                                         break;
 159                                 }
 160
 161                         if(process.get_state()>=Process::RUNNING)
 162                                 send_breakpoint(func, 0, flag);
 163                 }
 164         }
 165 }
 166
 167 void GlDbg::resume_from_break(Tool *tool)
 168 {
 169         if(!current_break)
 170                 return;
 171
 172         ToolList::iterator i = find(break_holders.begin(), break_holders.end(), tool);
 173         if(i!=break_holders.end())
 174                 break_holders.erase(i);
 175
 176         if(break_holders.empty())
 177                 process.resume();
 178 }
 179
 180 void GlDbg::quit(bool force)
 181 {
 182         if(!force && process.get_state()!=Process::INACTIVE)
 183                 throw runtime_error("Program is still running");
 184         done = true;
 185 }
 186
 187 void GlDbg::tick()
 188 {
 189         if(got_sigchld)
 190         {
 191                 got_sigchld = false;
 192                 stop_reason = process.check();
 193                 if((stop_reason>>8)==3)
 194                         flushing = true;
 195         }
 196
 197         Process::State pstate = process.get_state();
 198         if((pstate!=Process::INACTIVE && pstate!=Process::STOPPED) || flushing)
 199                 read_stream();
 200         else
 201         {
 202                 if(stop_reason)
 203                 {
 204                         if(stop_reason==0x100)
 205                                 printf("Target process exited normally\n");
 206                         else if((stop_reason>>8)==1)
 207                                 printf("Target process exited with status %d\n", stop_reason&0xFF);
 208                         else if((stop_reason>>8)==2)
 209                                 printf("Target process terminated with signal %d\n", stop_reason&0xFF);
 210                         else if((stop_reason>>8)==3)
 211                                 printf("Target process stopped by signal %d\n", stop_reason&0xFF);
 212
 213                         stop_reason = 0;
 214                 }
 215
 216                 char *line = readline("gldbg> ");
 217                 if(line)
 218                 {
 219                         try
 220                         {
 221                                 cmd_interp.execute(line);
 222                         }
 223                         catch(const exception &e)
 224                         {
 225                                 printf("%s\n", e.what());
 226                         }
 227                         free(line);
 228                 }
 229                 else if(pstate==Process::INACTIVE)
 230                         done = true;
 231         }
 232 }
 233
 234 void GlDbg::read_stream()
 235 {
 236         pollfd pfd = { sock_fd, POLLIN, 0 };
 237         int ret = poll(&pfd, 1, (flushing ? 0 : -1));
 238         if(ret>0)
 239         {
 240                 char rbuf[1024];
 241                 ret = read(sock_fd, rbuf, 1024);
 242                 if(ret>0)
 243                 {
 244                         buffer.append(rbuf, ret);
 245                         while(buffer.size()>buf_offset)
 246                         {
 247                                 const char *data = buffer.data()+buf_offset;
 248                                 unsigned len = buffer.size()-buf_offset;
 249                                 GlPacket *pkt = packet_receive_str(data, &len);
 250                                 if(!pkt)
 251                                         break;
 252
 253                                 unsigned short func;
 254                                 packet_read_short(pkt, (short *)&func);
 255                                 if(func==FUNC_GLDBREAK)
 256                                 {
 257                                         packet_read_short(pkt, (short *)&func);
 258                                         unsigned char flag;
 259                                         packet_read_char(pkt, (char *)&flag);
 260
 261                                         current_break = get_breakpoint(func, flag);
 262                                         bool announce = !current_break;
 263                                         if(current_break)
 264                                         {
 265                                                 break_holders = current_break->owners;
 266                                                 announce = current_break->has_owner(0);
 267                                         }
 268
 269                                         if(announce)
 270                                                 printf("Breakpoint: %s\n", get_function_name(func));
 271                                 }
 272
 273                                 for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 274                                         (*i)->decode(data, len);
 275                                 buf_offset += len;
 276                         }
 277                         if(buf_offset>8192)
 278                         {
 279                                 buffer.erase(0, buf_offset);
 280                                 buf_offset = 0;
 281                         }
 282                 }
 283         }
 284         else if(flushing)
 285         {
 286                 flushing = false;
 287
 288                 if(stop_reason)
 289                 {
 290                         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 291                                 (*i)->process_stopped(stop_reason);
 292
 293                         if(process.get_state()==Process::RUNNING)
 294                                 current_break = 0;
 295                 }
 296         }
 297 }
 298
 299 GlDbg::Breakpoint *GlDbg::get_breakpoint(unsigned short func, unsigned char flag)
 300 {
 301         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 302                 if(i->function==func && i->flag==flag)
 303                         return &*i;
 304
 305         return 0;
 306 }
 307
 308 void GlDbg::sighandler(int sig)
 309 {
 310         if(sig==SIGCHLD)
 311                 instance->got_sigchld = true;
 312 }
 313
 314
 315 GlDbg::Breakpoint::Breakpoint(unsigned short f, unsigned char l):
 316         function(f),
 317         flag(l)
 318 { }
 319
 320 void GlDbg::Breakpoint::add_owner(Tool *t)
 321 {
 322         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 323         if(i==owners.end())
 324                 owners.push_back(t);
 325 }
 326
 327 bool GlDbg::Breakpoint::has_owner(Tool *t) const
 328 {
 329         ToolList::const_iterator i = find(owners.begin(), owners.end(), t);
 330         return i!=owners.end();
 331 }
 332
 333 void GlDbg::Breakpoint::remove_owner(Tool *t)
 334 {
 335         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 336         if(i!=owners.end())
 337                 owners.erase(i);
 338 }