source/gldbg.cpp

   1 /* $Id$
   2
   3 This file is part of gldbg
   4 Copyright © 2009-2011  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the GPL
   6 */
   7
   8 #include <algorithm>
   9 #include <stdexcept>
  10 #include <cstdlib>
  11 #include <climits>
  12 #include <fcntl.h>
  13 #include <signal.h>
  14 #include <unistd.h>
  15 #include <sys/poll.h>
  16 #include <sys/socket.h>
  17 #include <readline/readline.h>
  18 #include "functions.h"
  19 #include "gldbg.h"
  20 #include "gldecoder.h"
  21 #include "packet.h"
  22 #include "strformat.h"
  23 #include "tool.h"
  24
  25 using namespace std;
  26
  27 GlDbg *GlDbg::instance = 0;
  28
  29 GlDbg::GlDbg(int argc, char **argv):
  30         cmd_interp(*this),
  31         process(vector<string>(argv+1, argv+argc)),
  32         buf_offset(0),
  33         flushing(false),
  34         got_sigchld(false),
  35         stop_reason(0),
  36         current_break(0)
  37 {
  38         instance = this;
  39
  40         char buf[PATH_MAX];
  41         unsigned len = readlink("/proc/self/exe", buf, sizeof(buf));
  42         string exe(buf, len);
  43         string::size_type slash = exe.rfind('/');
  44         process.setenv("LD_PRELOAD", (exe.substr(0, slash+1)+"glwrap.so"));
  45
  46         const list<Tool::Factory *> &factories = Tool::get_factories();
  47         for(list<Tool::Factory *>::const_iterator i=factories.begin(); i!=factories.end(); ++i)
  48                 tools.push_back((*i)->create(*this));
  49 }
  50
  51 GlDbg::~GlDbg()
  52 {
  53         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  54                 delete *i;
  55 }
  56
  57 int GlDbg::main()
  58 {
  59         signal(SIGINT, &sighandler);
  60         signal(SIGCHLD, &sighandler);
  61
  62         printf("GLdbg 0.0\n");
  63         printf("Copyright © 2009-2010 Mikkosoft Productions\n");
  64         printf("Type \"help\" for a list of commands\n");
  65
  66         while(1)
  67                 tick();
  68
  69         return 0;
  70 }
  71
  72 void GlDbg::launch()
  73 {
  74         if(process.get_state()!=Process::INACTIVE)
  75                 throw runtime_error("Program is already running");
  76
  77         int fds[2];
  78         socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
  79         sock_fd = fds[0];
  80
  81         int flags = fcntl(sock_fd, F_GETFD);
  82         fcntl(sock_fd, F_SETFD, flags|FD_CLOEXEC);
  83
  84         process.setenv("GLWRAP_FD", strformat("%d", fds[1]));
  85         process.setenv("GLWRAP_CTRL_FD", strformat("%d", fds[1]));
  86         process.launch();
  87         close(fds[1]);
  88
  89         breakpoints.clear();
  90         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  91                 (*i)->process_started();
  92 }
  93
  94 void GlDbg::send(GlPacket *pkt)
  95 {
  96         packet_send(pkt, sock_fd);
  97 }
  98
  99 void GlDbg::hold()
 100 {
 101         GlPacket *pkt = packet_begin(FUNC_GLDHOLD);
 102         send(pkt);
 103 }
 104
 105 void GlDbg::set_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 106 {
 107         Breakpoint *bp = (func ? get_breakpoint(func, flag) : 0);
 108         if(bp)
 109                 bp->add_owner(owner);
 110         else
 111         {
 112                 if(func)
 113                 {
 114                         breakpoints.push_back(Breakpoint(func, flag));
 115                         breakpoints.back().add_owner(owner);
 116                 }
 117
 118                 GlPacket *pkt = packet_begin(FUNC_GLDBREAK);
 119                 packet_write_short(pkt, func);
 120                 packet_write_char(pkt, flag);
 121                 packet_write_char(pkt, 0);
 122                 send(pkt);
 123         }
 124 }
 125
 126 void GlDbg::clear_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 127 {
 128         Breakpoint *bp = get_breakpoint(func, flag);
 129         if(bp)
 130         {
 131                 bp->remove_owner(owner);
 132                 if(bp->owners.empty())
 133                 {
 134                         if(current_break==bp)
 135                                 current_break = 0;
 136
 137                         // XXX Inefficient.  Should get_breakpoint() return an iterator?
 138                         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 139                                 if(i->function==func && i->flag==flag)
 140                                 {
 141                                         breakpoints.erase(i);
 142                                         break;
 143                                 }
 144
 145                         GlPacket *pkt = packet_begin(FUNC_GLDBREAK);
 146                         packet_write_short(pkt, func);
 147                         packet_write_char(pkt, 0);
 148                         packet_write_char(pkt, flag);
 149                         send(pkt);
 150                 }
 151         }
 152 }
 153
 154 void GlDbg::resume_from_break(Tool *tool)
 155 {
 156         if(!current_break)
 157                 return;
 158
 159         ToolList::iterator i = find(break_holders.begin(), break_holders.end(), tool);
 160         if(i!=break_holders.end())
 161                 break_holders.erase(i);
 162
 163         if(break_holders.empty())
 164                 process.resume();
 165 }
 166
 167 void GlDbg::quit(bool force)
 168 {
 169         if(!force && process.get_state()!=Process::INACTIVE)
 170                 throw runtime_error("Program is still running");
 171         exit(0);
 172 }
 173
 174 void GlDbg::tick()
 175 {
 176         if(got_sigchld)
 177         {
 178                 got_sigchld = false;
 179                 stop_reason = process.check();
 180                 if((stop_reason>>8)==3)
 181                         flushing = true;
 182         }
 183
 184         Process::State pstate = process.get_state();
 185         if((pstate!=Process::INACTIVE && pstate!=Process::STOPPED) || flushing)
 186                 read_stream();
 187         else
 188         {
 189                 if(stop_reason)
 190                 {
 191                         if(stop_reason==0x100)
 192                                 printf("Target process exited normally\n");
 193                         else if((stop_reason>>8)==1)
 194                                 printf("Target process exited with status %d\n", stop_reason&0xFF);
 195                         else if((stop_reason>>8)==2)
 196                                 printf("Target process terminated with signal %d\n", stop_reason&0xFF);
 197                         else if((stop_reason>>8)==3)
 198                                 printf("Target process stopped by signal %d\n", stop_reason&0xFF);
 199
 200                         stop_reason = 0;
 201                 }
 202
 203                 char *line = readline("gldbg> ");
 204                 if(line)
 205                 {
 206                         try
 207                         {
 208                                 cmd_interp.execute(line);
 209                         }
 210                         catch(const exception &e)
 211                         {
 212                                 printf("%s\n", e.what());
 213                         }
 214                         free(line);
 215                 }
 216                 else if(pstate==Process::INACTIVE)
 217                         exit(0);
 218         }
 219 }
 220
 221 void GlDbg::read_stream()
 222 {
 223         pollfd pfd = { sock_fd, POLLIN, 0 };
 224         int ret = poll(&pfd, 1, (flushing ? 0 : -1));
 225         if(ret>0)
 226         {
 227                 char rbuf[1024];
 228                 ret = read(sock_fd, rbuf, 1024);
 229                 if(ret>0)
 230                 {
 231                         buffer.append(rbuf, ret);
 232                         while(buffer.size()>buf_offset)
 233                         {
 234                                 const char *data = buffer.data()+buf_offset;
 235                                 unsigned len = buffer.size()-buf_offset;
 236                                 GlPacket *pkt = packet_receive_str(data, &len);
 237                                 if(!pkt)
 238                                         break;
 239
 240                                 unsigned short func;
 241                                 packet_read_short(pkt, (short *)&func);
 242                                 if(func==FUNC_GLDBREAK)
 243                                 {
 244                                         packet_read_short(pkt, (short *)&func);
 245                                         unsigned char flag;
 246                                         packet_read_char(pkt, (char *)&flag);
 247
 248                                         current_break = get_breakpoint(func, flag);
 249                                         bool announce = !current_break;
 250                                         if(current_break)
 251                                         {
 252                                                 break_holders = current_break->owners;
 253                                                 announce = current_break->has_owner(0);
 254                                         }
 255
 256                                         if(announce)
 257                                                 printf("Breakpoint: %s\n", get_function_name(func));
 258                                 }
 259
 260                                 for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 261                                         (*i)->decode(data, len);
 262                                 buf_offset += len;
 263                         }
 264                         if(buf_offset>8192)
 265                         {
 266                                 buffer.erase(0, buf_offset);
 267                                 buf_offset = 0;
 268                         }
 269                 }
 270         }
 271         else if(flushing)
 272         {
 273                 flushing = false;
 274
 275                 if(stop_reason)
 276                 {
 277                         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 278                                 (*i)->process_stopped(stop_reason);
 279
 280                         if(process.get_state()==Process::RUNNING)
 281                                 current_break = 0;
 282                 }
 283         }
 284 }
 285
 286 GlDbg::Breakpoint *GlDbg::get_breakpoint(unsigned short func, unsigned char flag)
 287 {
 288         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 289                 if(i->function==func && i->flag==flag)
 290                         return &*i;
 291
 292         return 0;
 293 }
 294
 295 void GlDbg::sighandler(int sig)
 296 {
 297         if(sig==SIGCHLD)
 298                 instance->got_sigchld = true;
 299 }
 300
 301
 302 GlDbg::Breakpoint::Breakpoint(unsigned short f, unsigned char l):
 303         function(f),
 304         flag(l)
 305 { }
 306
 307 void GlDbg::Breakpoint::add_owner(Tool *t)
 308 {
 309         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 310         if(i==owners.end())
 311                 owners.push_back(t);
 312 }
 313
 314 bool GlDbg::Breakpoint::has_owner(Tool *t) const
 315 {
 316         ToolList::const_iterator i = find(owners.begin(), owners.end(), t);
 317         return i!=owners.end();
 318 }
 319
 320 void GlDbg::Breakpoint::remove_owner(Tool *t)
 321 {
 322         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 323         if(i!=owners.end())
 324                 owners.erase(i);
 325 }