citadel/dynloader.c

   1 /*******************************************************
   2  *
   3  * Citadel Dynamic Loading Module
   4  * Written by Brian Costello
   5  * btx@calyx.net
   6  *
   7  * $Id$
   8  *
   9  ******************************************************/
  10
  11
  12 #include "sysdep.h"
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <dlfcn.h>
  16 #include <sys/types.h>
  17 #include <dirent.h>
  18 #include <strings.h>
  19 #include <syslog.h>
  20 #ifdef HAVE_PTHREAD_H
  21 #include <pthread.h>
  22 #endif
  23 #include <limits.h>
  24 #include <ctype.h>
  25 #include "dynloader.h"
  26 #include "citadel.h"
  27 #include "server.h"
  28 #include "sysdep_decls.h"
  29 #include "tools.h"
  30
  31 #ifndef HAVE_SNPRINTF
  32 #include <stdarg.h>
  33 #include "snprintf.h"
  34 #endif
  35
  36 struct LogFunctionHook *LogHookTable = NULL;
  37 struct CleanupFunctionHook *CleanupHookTable = NULL;
  38 struct SessionFunctionHook *SessionHookTable = NULL;
  39 struct UserFunctionHook *UserHookTable = NULL;
  40
  41 struct ProtoFunctionHook {
  42         void (*handler) (char *cmdbuf);
  43         char *cmd;
  44         char *desc;
  45         struct ProtoFunctionHook *next;
  46 } *ProtoHookList = NULL;
  47
  48 void CtdlRegisterProtoHook(void (*handler) (char *), char *cmd, char *desc)
  49 {
  50         struct ProtoFunctionHook *p = mallok(sizeof *p);
  51
  52         if (p == NULL) {
  53                 fprintf(stderr, "can't malloc new ProtoFunctionHook\n");
  54                 exit(EXIT_FAILURE);
  55         }
  56         p->handler = handler;
  57         p->cmd = cmd;
  58         p->desc = desc;
  59         p->next = ProtoHookList;
  60         ProtoHookList = p;
  61 }
  62
  63 int DLoader_Exec_Cmd(char *cmdbuf)
  64 {
  65         struct ProtoFunctionHook *p;
  66
  67         for (p = ProtoHookList; p; p = p->next) {
  68                 if (!strncasecmp(cmdbuf, p->cmd, 4)) {
  69                         p->handler(&cmdbuf[5]);
  70                         return 1;
  71                 }
  72         }
  73         return 0;
  74 }
  75
  76 void DLoader_Init(char *pathname)
  77 {
  78         void *fcn_handle;
  79         char dl_error[256];
  80         DIR *dir;
  81         int i;
  82         struct dirent *dptr;
  83         char *(*h_init_fcn) (void);
  84         char *dl_info;
  85
  86         char pathbuf[PATH_MAX];
  87
  88         if ((dir = opendir(pathname)) == NULL) {
  89                 perror("opendir");
  90                 exit(1);
  91         }
  92         while ((dptr = readdir(dir)) != NULL) {
  93                 if (dptr->d_name[0] == '.')
  94                         continue;
  95
  96                 snprintf(pathbuf, PATH_MAX, "%s/%s", pathname, dptr->d_name);
  97 #ifdef RTLD_NOW
  98                 if (!(fcn_handle = dlopen(pathbuf, RTLD_NOW)))
  99 #else                           /* OpenBSD */
 100                 if (!(fcn_handle = dlopen(pathbuf, DL_LAZY)))
 101 #endif
 102                 {
 103                         safestrncpy(dl_error, dlerror(), sizeof dl_error);
 104                         for (i=0; i<strlen(dl_error); ++i)
 105                                 if (!isprint(dl_error[i]))
 106                                         dl_error[i]='.';
 107                         fprintf(stderr, "DLoader_Init dlopen failed: %s\n",
 108                                 dl_error);
 109                         continue;
 110                 }
 111                 h_init_fcn = (char * (*)(void))
 112 #ifndef __OpenBSD__
 113                     dlsym(fcn_handle, "Dynamic_Module_Init");
 114 #else
 115                     dlsym(fcn_handle, "_Dynamic_Module_Init");
 116 #endif
 117
 118                 if (dlerror() != NULL) {
 119                         fprintf(stderr, "DLoader_Init dlsym failed\n");
 120                         continue;
 121                 }
 122                 dl_info = h_init_fcn();
 123
 124                 lprintf(3, "Loaded module: %s\n", dl_info);
 125         }       /* While */
 126 }
 127
 128
 129
 130 void CtdlRegisterLogHook(void (*fcn_ptr) (char *), int loglevel)
 131 {
 132
 133         struct LogFunctionHook *newfcn;
 134
 135         newfcn = (struct LogFunctionHook *)
 136             mallok(sizeof(struct LogFunctionHook));
 137         newfcn->next = LogHookTable;
 138         newfcn->h_function_pointer = fcn_ptr;
 139         newfcn->loglevel = loglevel;
 140         LogHookTable = newfcn;
 141
 142         lprintf(5, "Registered a new logging function\n");
 143 }
 144
 145
 146 void CtdlRegisterCleanupHook(void (*fcn_ptr) (void))
 147 {
 148
 149         struct CleanupFunctionHook *newfcn;
 150
 151         newfcn = (struct CleanupFunctionHook *)
 152             mallok(sizeof(struct CleanupFunctionHook));
 153         newfcn->next = CleanupHookTable;
 154         newfcn->h_function_pointer = fcn_ptr;
 155         CleanupHookTable = newfcn;
 156
 157         lprintf(5, "Registered a new cleanup function\n");
 158 }
 159
 160
 161 void CtdlRegisterSessionHook(void (*fcn_ptr) (void), int EventType)
 162 {
 163
 164         struct SessionFunctionHook *newfcn;
 165
 166         newfcn = (struct SessionFunctionHook *)
 167             mallok(sizeof(struct SessionFunctionHook));
 168         newfcn->next = SessionHookTable;
 169         newfcn->h_function_pointer = fcn_ptr;
 170         newfcn->eventtype = EventType;
 171         SessionHookTable = newfcn;
 172
 173         lprintf(5, "Registered a new session function (type %d)\n",
 174                 EventType);
 175 }
 176
 177
 178 void CtdlRegisterUserHook(void (*fcn_ptr) (char *, long), int EventType)
 179 {
 180
 181         struct UserFunctionHook *newfcn;
 182
 183         newfcn = (struct UserFunctionHook *)
 184             mallok(sizeof(struct UserFunctionHook));
 185         newfcn->next = UserHookTable;
 186         newfcn->h_function_pointer = fcn_ptr;
 187         newfcn->eventtype = EventType;
 188         UserHookTable = newfcn;
 189
 190         lprintf(5, "Registered a new user function (type %d)\n",
 191                 EventType);
 192 }
 193
 194
 195 void PerformSessionHooks(int EventType)
 196 {
 197         struct SessionFunctionHook *fcn;
 198
 199         for (fcn = SessionHookTable; fcn != NULL; fcn = fcn->next) {
 200                 if (fcn->eventtype == EventType) {
 201                         (*fcn->h_function_pointer) ();
 202                 }
 203         }
 204 }
 205
 206 void PerformLogHooks(int loglevel, char *logmsg)
 207 {
 208         struct LogFunctionHook *fcn;
 209
 210         for (fcn = LogHookTable; fcn != NULL; fcn = fcn->next) {
 211                 if (fcn->loglevel >= loglevel) {
 212                         (*fcn->h_function_pointer) (logmsg);
 213                 }
 214         }
 215 }
 216
 217 void PerformUserHooks(char *username, long usernum, int EventType)
 218 {
 219         struct UserFunctionHook *fcn;
 220
 221         for (fcn = UserHookTable; fcn != NULL; fcn = fcn->next) {
 222                 if (fcn->eventtype == EventType) {
 223                         (*fcn->h_function_pointer) (username, usernum);
 224                 }
 225         }
 226 }