dbquery

Query RDBMS and return S-expression
git clone https://logand.com/git/dbquery.git/
Log | Files | Refs | README

dbquery-pg.c (3454B)

      1 /*
      2   Copyright (C) 2012, 2013 Tomas Hlavaty <tom@logand.com>
      3 
      4   Permission is hereby granted, free of charge, to any person
      5   obtaining a copy of this software and associated documentation
      6   files (the "Software"), to deal in the Software without
      7   restriction, including without limitation the rights to use, copy,
      8   modify, merge, publish, distribute, sublicense, and/or sell copies
      9   of the Software, and to permit persons to whom the Software is
     10   furnished to do so, subject to the following conditions:
     11 
     12   The above copyright notice and this permission notice shall be
     13   included in all copies or substantial portions of the Software.
     14 
     15   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     16   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     17   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     18   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
     19   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
     20   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
     21   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
     22   DEALINGS IN THE SOFTWARE.
     23 */
     24 
     25 #include <stdio.h>
     26 #include <libpq-fe.h>
     27 
     28 #include "common.c"
     29 
     30 int main(int argc, char *argv[]) {
     31   if(argc != 2) die("usage: %s conninfo", argv[0]);
     32   PGconn *conn = PQconnectdb(argv[1]);
     33   if(!conn || CONNECTION_OK != PQstatus(conn)) die("error: connection failed");
     34   for(;;) {
     35     if(eof()) return 0;
     36     buf = heap;
     37     int i, j, cmd = rnum(), nargs = rnum();
     38     PGresult *z;
     39     {
     40       Oid atype[nargs];
     41       char *aval[nargs];
     42       int alen[nargs], afmt[nargs];
     43       char *q, *stm;
     44       switch(cmd) {
     45       case QUERY:
     46         q = rstr();
     47         for(i = 0; i < nargs; i++) {
     48           atype[i] = rnum();
     49           aval[i] = rstr();
     50           alen[i] = 0;
     51           afmt[i] = 0;
     52         }
     53         z = PQexecParams(conn, q, nargs, atype, (const char * const *) aval, alen, afmt, 0);
     54         if(PGRES_TUPLES_OK != PQresultStatus(z)) goto fail;
     55         goto rows;
     56       case PREPARE:
     57         stm = rstr();
     58         q = rstr();
     59         for(i = 0; i < nargs; i++)
     60           atype[i] = rnum();
     61         z = PQprepare(conn, stm, q, nargs, atype);
     62         if(PGRES_COMMAND_OK != PQresultStatus(z)) goto fail;
     63         pnum(cmd);
     64         goto done;
     65       case EXECUTE:
     66         stm = rstr();
     67         for(i = 0; i < nargs; i++) {
     68           aval[i] = rstr();
     69           alen[i] = 0;
     70           afmt[i] = 0;
     71         }
     72         z = PQexecPrepared(conn, stm, nargs, (const char * const *) aval, alen, afmt, 0);
     73         if(PGRES_TUPLES_OK != PQresultStatus(z)) goto fail;
     74         goto rows;
     75       default: die("unexpected command %d", cmd);
     76       }
     77     }
     78   rows:
     79     pnum(cmd);
     80     int n = PQntuples(z), m = PQnfields(z);
     81     pnum(n);
     82     pnum(m);
     83     for(j = 0; j < m; j++) {
     84       pnum(PQftype(z, j));
     85       pqstr(PQfname(z, j));
     86     }
     87     for(i = 0; i < n; i++) {
     88       for(j = 0; j < m; j++) {
     89         if(PQgetisnull(z, i, j))
     90           pnil();
     91         else
     92           pqstr(PQgetvalue(z, i, j));
     93         /* switch(PQftype(z, j)) { */
     94         /* case 1700: // float */
     95         /* case 23: // int */
     96         /*   pstr(PQgetvalue(z, i, j)); */
     97         /*   break; */
     98         /* default: */
     99         /*   pqstr(PQgetvalue(z, i, j)); */
    100         /* } */
    101       }
    102     }
    103     goto done;
    104   fail:
    105     pnum(ERROR);
    106     pqstr(PQresultErrorField(z, PG_DIAG_SQLSTATE));
    107     pqstr(PQerrorMessage(conn));
    108   done:
    109     fflush(stdout);
    110     PQclear(z);
    111   }
    112 }