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 #include <unistd.h>
  13
  14 #define CSG_BUFSIZE    512
  15
  16 pcre           *csg_curpat;        /* Compiled pattern from pcre */
  17 int             csg_curfile;       /* Which logfile is being searched */
  18 unsigned long   csg_curnum;        /* What numeric is doing a search */
  19 int             csg_matches;       /* How many lines have been returned so far */
  20 int             csg_maxmatches=0;  /* How many matches are allowed */
  21
  22 char            csg_readbuf[CSG_BUFSIZE];  /* Buffer */
  23 int             csg_bytesleft;     /* How much valid data there is in the buffer */
  24
  25 void csg_handleevents(int fd, short revents);
  26 int csg_dogrep(void *source, int cargc, char **cargv);
  27
  28 #if !defined(pread)
  29 extern ssize_t pread(int fd, void *buf, size_t count, off_t offset);
  30 #endif
  31
  32 void _init() {
  33   chanservaddcommand("grep",   QCMD_OPER, 1, csg_dogrep,   "Searches the logs.");
  34 }
  35
  36 void _fini() {
  37   chanservremovecommand("grep", csg_dogrep);
  38 }
  39
  40 int csg_dogrep(void *source, int cargc, char **cargv) {
  41   nick *sender=source;
  42   const char *errptr;
  43   int erroffset;
  44   int fd;
  45
  46   if (cargc<1) {
  47     chanservstdmessage(sender, QM_NOTENOUGHPARAMS, "grep");
  48     return CMD_ERROR;
  49   }
  50
  51   if (csg_maxmatches>0) {
  52     chanservsendmessage(sender, "Sorry, grep is currently busy - try later.");
  53     return CMD_ERROR;
  54   }
  55
  56   if (!(csg_curpat=pcre_compile(cargv[0], 0, &errptr, &erroffset, NULL))) {
  57     chanservsendmessage(sender, "Error in pattern at character %d: %s",erroffset,errptr);
  58     return CMD_ERROR;
  59   }
  60
  61   if ((fd=open("chanservlog.0",O_RDONLY))<0) {
  62     chanservsendmessage(sender, "Unable to open logfile.");
  63     free(csg_curpat);
  64     return CMD_ERROR;
  65   }
  66
  67   /* Initialise stuff for the match */
  68   csg_maxmatches=500;
  69   csg_matches=0;
  70   csg_curnum=sender->numeric;
  71   csg_curfile=0;
  72   csg_bytesleft=0;
  73
  74   registerhandler(fd, POLLIN, csg_handleevents);
  75   chanservsendmessage(sender, "Started grep for %s...",cargv[0]);
  76
  77   return CMD_OK;
  78 }
  79
  80 void csg_handleevents(int fd, short revents) {
  81   int res;
  82   nick *np=getnickbynumeric(csg_curnum);
  83   char *chp, *linestart;
  84   char filename[50];
  85   off_t pos;
  86
  87   /* If the target user has vanished, drop everything */
  88   if (!np) {
  89     deregisterhandler(fd, 1);
  90     free(csg_curpat);
  91     csg_maxmatches=0;
  92     return;
  93   }
  94
  95 retry:
  96   res=read(fd, csg_readbuf+csg_bytesleft, CSG_BUFSIZE-csg_bytesleft);
  97
  98   if (res<=0) {
  99     /* End of file (or error) */
 100     deregisterhandler(fd, 1);
 101     sprintf(filename,"chanservlog.%d",++csg_curfile);
 102     if ((fd=open(filename,O_RDONLY))>=0) {
 103       /* Found the next file */
 104       registerhandler(fd, POLLIN, csg_handleevents);
 105     } else {
 106       chanservstdmessage(np, QM_ENDOFLIST);
 107       free(csg_curpat);
 108       csg_maxmatches=0;
 109     }
 110
 111     return;
 112   }
 113
 114   linestart=chp=csg_readbuf;
 115   csg_bytesleft+=res;
 116
 117   while (csg_bytesleft) {
 118     csg_bytesleft--;
 119     if (*chp=='\r' || *chp=='\n' || *chp=='\0') {
 120       if (linestart==chp) {
 121         linestart=(++chp);
 122       } else {
 123         *chp++='\0';
 124         if (!pcre_exec(csg_curpat, NULL, linestart, strlen(linestart), 0, 0, NULL, 0)) {
 125           chanservsendmessage(np, "%s", linestart);
 126           if (++csg_matches >= csg_maxmatches) {
 127             chanservstdmessage(np, QM_ENDOFLIST);
 128             free(csg_curpat);
 129             deregisterhandler(fd, 1);
 130             csg_maxmatches=0;
 131           }
 132         }
 133         linestart=chp;
 134       }
 135     } else {
 136       chp++;
 137     }
 138   }
 139
 140   csg_bytesleft=(chp-linestart);
 141   memmove(csg_readbuf, linestart, csg_bytesleft);
 142
 143   /* BSD hack */
 144   pos=lseek(fd, 0, SEEK_CUR);
 145   if (!pread(fd, csg_readbuf+csg_bytesleft, 1, pos)) {
 146     /* EOF */
 147     goto retry;
 148   }
 149 }