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#include <stdio.h>
#include <stdlib.h>
#include <libpq-fe.h>
#include "../lisp_api.h"
value *hello_fun(env *e, value *args) {
printf("Hello from dynamically loaded module!\n");
return make_nil();
}
value *pg_execute(env *e, value *args) {
value *fst_arg = eval(e, car(args));
value *snd_arg = eval(e, car(cdr(args)));
if (fst_arg->type != VT_STRING) {
printf("not a string:");
println_value(fst_arg);
return make_nil(); //TODO: make error
}
if (snd_arg->type != VT_STRING) {
printf("not a string:");
println_value(snd_arg);
return make_nil(); //TODO: make error
}
const char *conn_str = fst_arg->as.str;
const char *query_str = snd_arg->as.str;
PGconn *conn = PQconnectdb(conn_str);
if (PQstatus(conn) != CONNECTION_OK) {
fprintf(stderr, "Connection failed: %s", PQerrorMessage(conn));
PQfinish(conn);
return make_nil(); //TODO: make error
}
PGresult *res = PQexec(conn, query_str);
if (PQresultStatus(res) != PGRES_TUPLES_OK) {
fprintf(stderr, "Query failed: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return make_nil(); //TODO: make error
}
int rows = PQntuples(res);
int cols = PQnfields(res);
value *table = make_nil();
for (int row = 0; row < rows; row++) {
value *row_val = make_nil();
for (int col = 0; col < cols; col++) {
switch (PQftype(res, col)) {
case 23:
row_val=cons(make_int(atoi(PQgetvalue(res, row, col))), row_val);
break;
case 1700:
case 20:
row_val=cons(make_int(atof(PQgetvalue(res, row, col))), row_val);
break;
default:
const char *str;
row_val=cons(make_string(PQgetvalue(res, row, col)), row_val);
break;
}
}
table = cons(reverse(row_val), table);
}
PQclear(res);
PQfinish(conn);
table = reverse(table);
return table;
}
module_export *module_init() {
static module_export exports[2];
exports[0].name = "pg_execute";
exports[0].v = make_procedure(&pg_execute);
exports[1].name = NULL;
exports[1].v = NULL;
return exports;
}
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