chanserv/chanservgrep.c

   1
   2 #include "chanserv.h"
   3 #include "../core/events.h"
   4 #include <pcre.h>
   5 #include <sys/poll.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <fcntl.h>
   9 #include <unistd.h>
  10 #include <string.h>
  11 #include <stdio.h>
  12
  13 #define CSG_BUFSIZE    512
  14
  15 pcre           *csg_curpat;        /* Compiled pattern from pcre */
  16 int             csg_curfile;       /* Which logfile is being searched */
  17 unsigned long   csg_curnum;        /* What numeric is doing a search */
  18 int             csg_matches;       /* How many lines have been returned so far */
  19 int             csg_maxmatches=0;  /* How many matches are allowed */
  20
  21 char            csg_readbuf[CSG_BUFSIZE];  /* Buffer */
  22 int             csg_bytesleft;     /* How much valid data there is in the buffer */
  23
  24 void csg_handleevents(int fd, short revents);
  25 int csg_dogrep(void *source, int cargc, char **cargv);
  26
  27 void _init() {
  28   chanservaddcommand("grep",   QCMD_OPER, 1, csg_dogrep,   "Searches the logs.");
  29 }
  30
  31 void _fini() {
  32   chanservremovecommand("grep", csg_dogrep);
  33 }
  34
  35 int csg_dogrep(void *source, int cargc, char **cargv) {
  36   nick *sender=source;
  37   const char *errptr;
  38   int erroffset;
  39   int fd;
  40
  41   if (cargc<1) {
  42     chanservstdmessage(sender, QM_NOTENOUGHPARAMS, "grep");
  43     return CMD_ERROR;
  44   }
  45
  46   if (csg_maxmatches>0) {
  47     chanservsendmessage(sender, "Sorry, grep is currently busy - try later.");
  48     return CMD_ERROR;
  49   }
  50
  51   if (!(csg_curpat=pcre_compile(cargv[0], 0, &errptr, &erroffset, NULL))) {
  52     chanservsendmessage(sender, "Error in pattern at character %d: %s",erroffset,errptr);
  53     return CMD_ERROR;
  54   }
  55
  56   if ((fd=open("chanservlog.0",O_RDONLY))<0) {
  57     chanservsendmessage(sender, "Unable to open logfile.");
  58     free(csg_curpat);
  59     return CMD_ERROR;
  60   }
  61
  62   /* Initialise stuff for the match */
  63   csg_maxmatches=500;
  64   csg_matches=0;
  65   csg_curnum=sender->numeric;
  66   csg_curfile=0;
  67   csg_bytesleft=0;
  68
  69   registerhandler(fd, POLLIN, csg_handleevents);
  70   chanservsendmessage(sender, "Started grep for %s...",cargv[0]);
  71
  72   return CMD_OK;
  73 }
  74
  75 void csg_handleevents(int fd, short revents) {
  76   int res;
  77   nick *np=getnickbynumeric(csg_curnum);
  78   char *chp, *linestart;
  79   char filename[50];
  80   off_t pos;
  81
  82   /* If the target user has vanished, drop everything */
  83   if (!np) {
  84     deregisterhandler(fd, 1);
  85     free(csg_curpat);
  86     csg_maxmatches=0;
  87     return;
  88   }
  89
  90 retry:
  91   res=read(fd, csg_readbuf+csg_bytesleft, CSG_BUFSIZE-csg_bytesleft);
  92
  93   if (res<=0) {
  94     /* End of file (or error) */
  95     deregisterhandler(fd, 1);
  96     sprintf(filename,"chanservlog.%d",++csg_curfile);
  97     if ((fd=open(filename,O_RDONLY))>=0) {
  98       /* Found the next file */
  99       registerhandler(fd, POLLIN, csg_handleevents);
 100     } else {
 101       chanservstdmessage(np, QM_ENDOFLIST);
 102       free(csg_curpat);
 103       csg_maxmatches=0;
 104     }
 105
 106     return;
 107   }
 108
 109   linestart=chp=csg_readbuf;
 110   csg_bytesleft+=res;
 111
 112   while (csg_bytesleft) {
 113     csg_bytesleft--;
 114     if (*chp=='\r' || *chp=='\n' || *chp=='\0') {
 115       if (linestart==chp) {
 116         linestart=(++chp);
 117       } else {
 118         *chp++='\0';
 119         if (!pcre_exec(csg_curpat, NULL, linestart, strlen(linestart), 0, 0, NULL, 0)) {
 120           chanservsendmessage(np, "%s", linestart);
 121           if (++csg_matches >= csg_maxmatches) {
 122             chanservstdmessage(np, QM_ENDOFLIST);
 123             free(csg_curpat);
 124             deregisterhandler(fd, 1);
 125             csg_maxmatches=0;
 126           }
 127         }
 128         linestart=chp;
 129       }
 130     } else {
 131       chp++;
 132     }
 133   }
 134
 135   csg_bytesleft=(chp-linestart);
 136   memmove(csg_readbuf, linestart, csg_bytesleft);
 137
 138   /* BSD hack */
 139   pos=lseek(fd, 0, SEEK_CUR);
 140   if (!pread(fd, csg_readbuf+csg_bytesleft, 1, pos)) {
 141     /* EOF */
 142     goto retry;
 143   }
 144 }