checktag.c

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#include "slurp.h"
#include "byte.h"
#include "stralloc.h"
#include "scan.h"
#include "fmt.h"
#include "cookie.h"
#include "makehash.h"
#include "logmsg.h"
#include "errtxt.h"
#include "subscribe.h"
#include <unistd.h>
#include <libpq-fe.h>
 
#define WHO "checktag"

 
extern PGconn *pgsql;
 
static stralloc key = {0};
static stralloc line = {0};
static char strnum[FMT_ULONG];
static char newcookie[COOKIE];

 
const char *checktag(const char *dir,unsigned long num,unsigned long listno,const char *action,const char *seed,const char *hash)
{
  PGresult *result;                              /*  int row; */
  const char *table = (char *) 0;
  const char *r;
 
  if ((r = opensql(dir,&table))) {
    if (*r) return r;
    if (!seed) return (char *) 0;                /* no data - accept */
 
    strnum[fmt_ulong(strnum,num)] = '\0';        /* message nr ->string*/
 
    switch (openreadclose("key",&key,32)) {
      case -1: return ERR_READ_KEY;
      case  0: return ERR_NOEXIST_KEY;
    }
 
    cookie(newcookie,key.s,key.len,strnum,seed,action);
 
    if (byte_diff(hash,COOKIE,newcookie)) return "";
    else return (char *) 0;
 
  } else {
 
    /* SELECT msgnum FROM table_cookie WHERE msgnum=num and cookie='hash' */
    /* succeeds only is everything correct. 'hash' is quoted since it is  */
    /* potentially hostile. */
 
    if (listno) {                                /* only for slaves */
      if (!stralloc_copys(&line,"SELECT listno FROM ")) return ERR_NOMEM;
      if (!stralloc_cats(&line,table)) return ERR_NOMEM;
      if (!stralloc_cats(&line,"_mlog WHERE listno=")) return ERR_NOMEM;
      if (!stralloc_catb(&line,strnum,fmt_ulong(strnum,listno))) return ERR_NOMEM;
      if (!stralloc_cats(&line," AND msgnum=")) return ERR_NOMEM;
      if (!stralloc_catb(&line,strnum,fmt_ulong(strnum,num))) return ERR_NOMEM;
      if (!stralloc_cats(&line," AND done > 3")) return ERR_NOMEM;
      if (!stralloc_0(&line)) return ERR_NOMEM;
 
      result = PQexec(pgsql,line.s);
      if (result == NULL)
        return (PQerrorMessage(pgsql));
      if (PQresultStatus(result) != PGRES_TUPLES_OK)
         return (char *) (PQresultErrorMessage(result));
      if (PQntuples(result) > 0) {
        PQclear(result);
        return("");
      } else
        PQclear(result);
    }
 
    if (!stralloc_copys(&line,"SELECT msgnum FROM ")) return ERR_NOMEM;
    if (!stralloc_cats(&line,table)) return ERR_NOMEM;
    if (!stralloc_cats(&line,"_cookie WHERE msgnum=")) return ERR_NOMEM;
    if (!stralloc_catb(&line,strnum,fmt_ulong(strnum,num))) return ERR_NOMEM;
    if (!stralloc_cats(&line," and cookie='")) return ERR_NOMEM;
    if (!stralloc_catb(&line,strnum,fmt_str(strnum,hash))) return ERR_NOMEM;
    if (!stralloc_cats(&line,"'")) return ERR_NOMEM;
    if (!stralloc_0(&line)) return ERR_NOMEM;
 
    result = PQexec(pgsql,line.s);
    if (result == NULL)
      return (PQerrorMessage(pgsql));
    if (PQresultStatus(result) != PGRES_TUPLES_OK)
      return (char *) (PQresultErrorMessage(result));
    if(PQntuples(result) < 0) {
      PQclear( result );
      return("");
    }
 
    PQclear(result);
    if (listno)
      loginfo(dir,num,listno,0L,3);              /* non-ess mysql logging */
    return (char *)0;
  }
}