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 <unistd.h>
  33 #include <sys/types.h>
  34 #include <stdio.h>
  35
  36 extern ServerConfig* Config;
  37
  38 DLLManager::DLLManager(const char *fname)
  39 {
  40         err = NULL;
  41
  42         if (!strstr(fname,".so"))
  43         {
  44                 err = "This doesn't look like a module file to me...";
  45                 return;
  46         }
  47 #ifdef STATIC_LINK
  48         this->staticname[0] = '\0';
  49         log(DEBUG,"Loading core-compiled module '%s'",fname);
  50         for (int j = 0; modsyms[j].name; j++)
  51         {
  52                 log(DEBUG,"Check %s",modsyms[j].name);
  53                 if (!strcmp(modsyms[j].name,fname))
  54                 {
  55                         log(DEBUG,"Found %s",fname);
  56                         strlcpy(this->staticname,fname,1020);
  57                         err = 0;
  58                         return;
  59                 }
  60         }
  61         err = "Module is not statically compiled into the ircd";
  62 #else
  63         // Copy the library to a temp location, this makes recompiles
  64         // a little safer if the ircd is running at the time as the
  65         // shared libraries are mmap()ed and not doing this causes
  66         // segfaults.
  67         FILE* x = fopen(fname,"rb");
  68         if (!x)
  69         {
  70                 err = strerror(errno);
  71                 return;
  72         }
  73         char tmpfile_template[255];
  74         char buffer[65536];
  75         snprintf(tmpfile_template, 255, "%s/inspircd_file.so.%d.XXXXXXXXXX",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         while (!feof(x))
  84         {
  85                 int n = fread(buffer, 1, 65535, x);
  86                 if (n)
  87                 {
  88                         int written = write(fd,buffer,n);
  89                         if (written != n)
  90                         {
  91                                 fclose(x);
  92                                 err = strerror(errno);
  93                                 return;
  94                         }
  95                 }
  96         }
  97         // Try to open the library now and get any error message.
  98
  99         h = dlopen(tmpfile_template, RTLD_NOW );
 100
 101         if (!h)
 102         {
 103                 err = dlerror();
 104                 return;
 105         }
 106         if (close(fd) == -1)
 107                 err = strerror(errno);
 108         if (fclose(x) == EOF)
 109                 err = strerror(errno);
 110
 111         // We can delete the tempfile once it's loaded, leaving just the inode.
 112         if (!err && !Config->debugging)
 113         {
 114                 if (unlink(tmpfile_template) == -1)
 115                         err = strerror(errno);
 116         }
 117 #endif
 118 }
 119
 120 DLLManager::~DLLManager()
 121 {
 122 #ifndef STATIC_LINK
 123         // close the library if it isn't null
 124         if (h != 0)
 125         dlclose(h);
 126 #endif
 127 }
 128
 129
 130
 131 #ifdef STATIC_LINK
 132
 133 bool DLLManager::GetSymbol(initfunc* &v, const char *sym_name)
 134 {
 135         log(DEBUG,"Symbol search...");
 136         for (int j = 0; modsyms[j].name; j++)
 137         {
 138                 if (!strcmp(this->staticname,modsyms[j].name))
 139                 {
 140                         log(DEBUG,"Loading symbol...");
 141                         v = modsyms[j].value;
 142                         err = 0;
 143                         return true;
 144                 }
 145         }
 146         err = "Module symbol missing from the core";
 147         return false;
 148 }
 149
 150 #else
 151
 152 bool DLLManager::GetSymbol(void** v, const char* sym_name)
 153 {
 154         // try extract a symbol from the library
 155         // get any error message is there is any
 156
 157         if (h)
 158         {
 159                 *v = dlsym(h, sym_name);
 160                 err = dlerror();
 161                 return !err;
 162         }
 163         else
 164         {
 165                 return false;
 166         }
 167 }
 168
 169 #endif
 170
 171 DLLFactoryBase::DLLFactoryBase(const char* fname, const char* factory) : DLLManager(fname)
 172 {
 173         // try get the factory function if there is no error yet
 174         factory_func = 0;
 175
 176         if (!LastError())
 177         {
 178 #ifdef STATIC_LINK
 179                 GetSymbol( factory_func, factory ? factory : "init_module" );
 180 #else
 181                 GetSymbol( (void **)&factory_func, factory ? factory : "init_module" );
 182 #endif
 183         }
 184 }
 185
 186
 187 DLLFactoryBase::~DLLFactoryBase()
 188 {
 189 }