citadel/modules/wiki/serv_wiki.c

   1 /*
   2  * $Id$
   3  *
   4  * Server-side module for Wiki rooms.  This will handle things like version control.
   5  *
   6  * Copyright (c) 2009-2009 by the citadel.org team
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 3 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include "sysdep.h"
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <stdio.h>
  27 #include <fcntl.h>
  28 #include <signal.h>
  29 #include <pwd.h>
  30 #include <errno.h>
  31 #include <ctype.h>
  32 #include <sys/types.h>
  33
  34 #if TIME_WITH_SYS_TIME
  35 # include <sys/time.h>
  36 # include <time.h>
  37 #else
  38 # if HAVE_SYS_TIME_H
  39 #  include <sys/time.h>
  40 # else
  41 #  include <time.h>
  42 # endif
  43 #endif
  44
  45 #include <sys/wait.h>
  46 #include <string.h>
  47 #include <limits.h>
  48 #include <libcitadel.h>
  49 #include "citadel.h"
  50 #include "server.h"
  51 #include "citserver.h"
  52 #include "support.h"
  53 #include "config.h"
  54 #include "control.h"
  55 #include "room_ops.h"
  56 #include "user_ops.h"
  57 #include "policy.h"
  58 #include "database.h"
  59 #include "msgbase.h"
  60 #include "euidindex.h"
  61 #include "ctdl_module.h"
  62
  63 /*
  64  * Before allowing a wiki page save to execute, we have to perform version control.
  65  * This involves fetching the old version of the page if it exists... FIXME finish this
  66  */
  67 int wiki_upload_beforesave(struct CtdlMessage *msg) {
  68         struct CitContext *CCC = CC;
  69         long old_msgnum = (-1L);
  70         struct CtdlMessage *old_msg = NULL;
  71         long history_msgnum = (-1L);
  72         struct CtdlMessage *history_msg = NULL;
  73         char diff_old_filename[PATH_MAX];
  74         char diff_new_filename[PATH_MAX];
  75         char diff_cmd[PATH_MAX];
  76         FILE *fp;
  77         int rv;
  78         char history_page[1024];
  79         char boundary[256];
  80         int nbytes = 0;
  81         char *diffbuf = NULL;
  82         size_t diffbuf_len = 0;
  83
  84         if (!CCC->logged_in) return(0); /* Only do this if logged in. */
  85
  86         /* Is this a room with a Wiki in it, don't run this hook. */
  87         if (CCC->room.QRdefaultview != VIEW_WIKI) {
  88                 return(0);
  89         }
  90
  91         /* If this isn't a MIME message, don't bother. */
  92         if (msg->cm_format_type != 4) return(0);
  93
  94         /* If there's no EUID we can't do this. */
  95         if (msg->cm_fields['E'] == NULL) return(0);
  96
  97         /* If there's no message text, obviously this is all b0rken and shouldn't happen at all */
  98         if (msg->cm_fields['M'] == NULL) return(0);
  99
 100         /* See if we can retrieve the previous version. */
 101         old_msgnum = locate_message_by_euid(msg->cm_fields['E'], &CCC->room);
 102         if (old_msgnum <= 0L) return(0);
 103         snprintf(history_page, sizeof history_page, "%s_HISTORY_", msg->cm_fields['E']);
 104
 105         old_msg = CtdlFetchMessage(old_msgnum, 1);
 106         if (old_msg == NULL) return(0);
 107
 108         if (old_msg->cm_fields['M'] == NULL) {          /* old version is corrupt? */
 109                 CtdlFreeMessage(old_msg);
 110                 return(0);
 111         }
 112
 113         /* If no changes were made, don't bother saving it again */
 114         if (!strcmp(msg->cm_fields['M'], old_msg->cm_fields['M'])) {
 115                 CtdlFreeMessage(old_msg);
 116                 return(1);
 117         }
 118
 119         /*
 120          * Generate diffs
 121          */
 122         CtdlMakeTempFileName(diff_old_filename, sizeof diff_old_filename);
 123         CtdlMakeTempFileName(diff_new_filename, sizeof diff_new_filename);
 124
 125         fp = fopen(diff_old_filename, "w");
 126         rv = fwrite(old_msg->cm_fields['M'], strlen(old_msg->cm_fields['M']), 1, fp);
 127         fclose(fp);
 128         CtdlFreeMessage(old_msg);
 129
 130         fp = fopen(diff_new_filename, "w");
 131         rv = fwrite(msg->cm_fields['M'], strlen(msg->cm_fields['M']), 1, fp);
 132         fclose(fp);
 133
 134         diffbuf_len = 0;
 135         diffbuf = NULL;
 136         snprintf(diff_cmd, sizeof diff_cmd, "diff -u %s %s", diff_old_filename, diff_new_filename);
 137         fp = popen(diff_cmd, "r");
 138         if (fp != NULL) {
 139                 do {
 140                         diffbuf = realloc(diffbuf, diffbuf_len + 1025);
 141                         nbytes = fread(&diffbuf[diffbuf_len], 1, 1024, fp);
 142                         diffbuf_len += nbytes;
 143                 } while (nbytes == 1024);
 144                 diffbuf[diffbuf_len] = 0;
 145                 pclose(fp);
 146         }
 147         CtdlLogPrintf(CTDL_DEBUG, "diff length is %d bytes\n", diffbuf_len);
 148
 149         unlink(diff_old_filename);
 150         unlink(diff_new_filename);
 151
 152         /* Determine whether this was a bogus (empty) edit */
 153         if ((diffbuf_len = 0) && (diffbuf != NULL)) {
 154                 free(diffbuf);
 155                 diffbuf = NULL;
 156         }
 157         if (diffbuf == NULL) {
 158                 return(1);              /* No changes at all?  Abandon the post entirely! */
 159         }
 160
 161         free(diffbuf);  /* FIXME do something with it */
 162
 163         /* Now look for the existing edit history */
 164
 165         history_msgnum = locate_message_by_euid(history_page, &CCC->room);
 166         history_msg = NULL;
 167         if (history_msgnum > 0L) {
 168                 history_msg = CtdlFetchMessage(old_msgnum, 1);
 169         }
 170
 171         /* Create a new history message if necessary */
 172         if (history_msg == NULL) {
 173                 history_msg = malloc(sizeof(struct CtdlMessage));
 174                 memset(history_msg, 0, sizeof(struct CtdlMessage));
 175                 history_msg->cm_magic = CTDLMESSAGE_MAGIC;
 176                 history_msg->cm_anon_type = MES_NORMAL;
 177                 history_msg->cm_format_type = FMT_RFC822;
 178                 history_msg->cm_fields['A'] = strdup("Citadel");
 179                 history_msg->cm_fields['R'] = strdup(CCC->room.QRname);
 180                 snprintf(boundary, sizeof boundary, "Citadel--Multipart--%04x--%08lx", getpid(), time(NULL));
 181                 history_msg->cm_fields['M'] = malloc(1024);
 182                 snprintf(history_msg->cm_fields['M'], 1024,
 183                         "Content-type: multipart/mixed; boundary=\"%s\"\n\n"
 184                         "This is a Citadel wiki history encoded as multipart MIME.\n"
 185                         "--%s--\n"
 186                         ,
 187                         boundary, boundary
 188                 );
 189         }
 190
 191         /* Update the history message (regardless of whether it's new or existing) */
 192         /* FIXME now do something with it */
 193         CtdlLogPrintf(CTDL_DEBUG, "\033[31m%s\033[0m", history_msg->cm_fields['M']);
 194
 195         /* FIXME */
 196
 197         free(history_msg);
 198         return(0);
 199 }
 200
 201
 202 /*
 203  * Module initialization
 204  */
 205 CTDL_MODULE_INIT(wiki)
 206 {
 207         if (!threading)
 208         {
 209                 CtdlRegisterMessageHook(wiki_upload_beforesave, EVT_BEFORESAVE);
 210         }
 211
 212         /* return our Subversion id for the Log */
 213         return "$Id$";
 214 }