src/dynamic.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 using namespace std;
  18
  19 #include "inspircd_config.h"
  20 #include "configreader.h"
  21 #include "globals.h"
  22 #include "dynamic.h"
  23
  24 #ifndef STATIC_LINK
  25 #include <dlfcn.h>
  26 #else
  27 #include "modlist.h"
  28 #endif
  29
  30 #include "inspstring.h"
  31 #include "helperfuncs.h"
  32 #include "inspircd.h"
  33 #include <unistd.h>
  34 #include <sys/types.h>
  35 #include <stdio.h>
  36
  37 DLLManager::DLLManager(InspIRCd* ServerInstance, const char *fname)
  38 {
  39         err = NULL;
  40
  41         if (!strstr(fname,".so"))
  42         {
  43                 err = "This doesn't look like a module file to me...";
  44                 return;
  45         }
  46 #ifdef STATIC_LINK
  47         this->staticname[0] = '\0';
  48         ServerInstance->Log(DEBUG,"Loading core-compiled module '%s'",fname);
  49         for (int j = 0; modsyms[j].name; j++)
  50         {
  51                 ServerInstance->Log(DEBUG,"Check %s",modsyms[j].name);
  52                 if (!strcmp(modsyms[j].name,fname))
  53                 {
  54                         ServerInstance->Log(DEBUG,"Found %s",fname);
  55                         strlcpy(this->staticname,fname,1020);
  56                         err = 0;
  57                         return;
  58                 }
  59         }
  60         err = "Module is not statically compiled into the ircd";
  61 #else
  62         // Copy the library to a temp location, this makes recompiles
  63         // a little safer if the ircd is running at the time as the
  64         // shared libraries are mmap()ed and not doing this causes
  65         // segfaults.
  66         FILE* x = fopen(fname,"rb");
  67         if (!x)
  68         {
  69                 err = strerror(errno);
  70                 return;
  71         }
  72         ServerInstance->Log(DEBUG,"Opened module file %s",fname);
  73         char tmpfile_template[255];
  74         char buffer[65536];
  75         snprintf(tmpfile_template, 255, "%s/inspircd_file.so.%d.XXXXXXXXXX",ServerInstance->Config->TempDir,getpid());
  76         int fd = mkstemp(tmpfile_template);
  77         if (fd == -1)
  78         {
  79                 fclose(x);
  80                 err = strerror(errno);
  81                 return;
  82         }
  83         ServerInstance->Log(DEBUG,"Copying %s to %s",fname, tmpfile_template);
  84         while (!feof(x))
  85         {
  86                 int n = fread(buffer, 1, 65535, x);
  87                 if (n)
  88                 {
  89                         int written = write(fd,buffer,n);
  90                         if (written != n)
  91                         {
  92                                 fclose(x);
  93                                 err = strerror(errno);
  94                                 return;
  95                         }
  96                 }
  97         }
  98         ServerInstance->Log(DEBUG,"Copied entire file.");
  99         // Try to open the library now and get any error message.
 100
 101         if (close(fd) == -1)
 102                 err = strerror(errno);
 103         if (fclose(x) == EOF)
 104                 err = strerror(errno);
 105
 106         h = dlopen(fname, RTLD_NOW|RTLD_LOCAL);
 107         if (!h)
 108         {
 109                 ServerInstance->Log(DEBUG,"dlerror occured!");
 110                 err = (char*)dlerror();
 111                 return;
 112         }
 113
 114         ServerInstance->Log(DEBUG,"Finished loading '%s': %0x",tmpfile_template, h);
 115
 116         // We can delete the tempfile once it's loaded, leaving just the inode.
 117         if (!err && !ServerInstance->Config->debugging)
 118         {
 119                 ServerInstance->Log(DEBUG,"Deleteting %s",tmpfile_template);
 120                 if (unlink(tmpfile_template) == -1)
 121                         err = strerror(errno);
 122         }
 123 #endif
 124 }
 125
 126 DLLManager::~DLLManager()
 127 {
 128 #ifndef STATIC_LINK
 129         // close the library if it isn't null
 130         if (h)
 131                 dlclose(h);
 132 #endif
 133 }
 134
 135
 136
 137 #ifdef STATIC_LINK
 138
 139 bool DLLManager::GetSymbol(initfunc* &v, const char *sym_name)
 140 {
 141         for (int j = 0; modsyms[j].name; j++)
 142         {
 143                 if (!strcmp(this->staticname,modsyms[j].name))
 144                 {
 145                         v = modsyms[j].value;
 146                         err = 0;
 147                         return true;
 148                 }
 149         }
 150         err = "Module symbol missing from the core";
 151         return false;
 152 }
 153
 154 #else
 155
 156 bool DLLManager::GetSymbol(void** v, const char* sym_name)
 157 {
 158         // try extract a symbol from the library
 159         // get any error message is there is any
 160
 161         if (h)
 162         {
 163                 dlerror(); // clear value
 164                 *v = dlsym(h, sym_name);
 165                 err = (char*)dlerror();
 166                 if (!*v || err)
 167                         return false;
 168         }
 169
 170         if (err)
 171         {
 172                 return false;
 173         }
 174         else
 175         {
 176                 return true;
 177         }
 178 }
 179
 180 #endif
 181
 182 DLLFactoryBase::DLLFactoryBase(InspIRCd* Instance, const char* fname, const char* symbol) : DLLManager(Instance, fname)
 183 {
 184         // try get the factory function if there is no error yet
 185         factory_func = 0;
 186
 187         if (!LastError())
 188         {
 189 #ifdef STATIC_LINK
 190                 if (!GetSymbol( factory_func, symbol ? symbol : "init_module"))
 191 #else
 192                 if (!GetSymbol( (void **)&factory_func, symbol ? symbol : "init_module"))
 193 #endif
 194                 {
 195                         throw ModuleException("Missing init_module() entrypoint!");
 196                 }
 197         }
 198 }
 199
 200 DLLFactoryBase::~DLLFactoryBase()
 201 {
 202 }
 203