1 /* $Cambridge: exim/src/src/lookups/pgsql.c,v 1.4 2006/02/07 11:19:01 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2006 */
8 /* See the file NOTICE for conditions of use and distribution. */
10 /* Thanks to Petr Cech for contributing the original code for these
11 functions. Thanks to Joachim Wieland for the initial patch for the Unix domain
15 #include "lf_functions.h"
16 #include "pgsql.h" /* The local header */
18 /* We can't just compile this code and allow the library mechanism to omit the
19 functions if they are not wanted, because we need to have the PGSQL header
20 available for compiling. Therefore, compile these functions only if
21 LOOKUP_PGSQL is defined. However, some compilers don't like compiling empty
22 modules, so keep them happy with a dummy when skipping the rest. Make it
23 reference itself to stop picky compilers complaining that it is unused, and put
24 in a dummy argument to stop even pickier compilers complaining about infinite
28 static void dummy(int x) { dummy(x-1); }
32 #include <libpq-fe.h> /* The system header */
34 /* Structure and anchor for caching connections. */
36 typedef struct pgsql_connection {
37 struct pgsql_connection *next;
42 static pgsql_connection *pgsql_connections = NULL;
46 /*************************************************
48 *************************************************/
50 /* See local README for interface description. */
53 pgsql_open(uschar *filename, uschar **errmsg)
55 return (void *)(1); /* Just return something non-null */
60 /*************************************************
62 *************************************************/
64 /* See local README for interface description. */
70 while ((cn = pgsql_connections) != NULL)
72 pgsql_connections = cn->next;
73 DEBUG(D_lookup) debug_printf("close PGSQL connection: %s\n", cn->server);
80 /*************************************************
81 * Internal search function *
82 *************************************************/
84 /* This function is called from the find entry point to do the search for a
85 single server. The server string is of the form "server/dbname/user/password".
87 PostgreSQL supports connections through Unix domain sockets. This is usually
88 faster and costs less cpu time than a TCP/IP connection. However it can only be
89 used if the mail server runs on the same machine as the database server. A
90 configuration line for PostgreSQL via Unix domain sockets looks like this:
92 hide pgsql_servers = (/tmp/.s.PGSQL.5432)/db/user/password[:<nextserver>]
94 We enclose the path name in parentheses so that its slashes aren't visually
95 confused with the delimeters for the other pgsql_server settings.
97 For TCP/IP connections, the server is a host name and optional port (with a
101 1) All three '/' must be present.
102 2) If host is omitted the local unix socket is used.
105 query the query string
106 server the server string; this is in dynamic memory and can be updated
107 resultptr where to store the result
108 errmsg where to point an error message
109 defer_break TRUE if no more servers are to be tried after DEFER
110 do_cache set FALSE if data is changed
112 Returns: OK, FAIL, or DEFER
116 perform_pgsql_search(uschar *query, uschar *server, uschar **resultptr,
117 uschar **errmsg, BOOL *defer_break, BOOL *do_cache)
119 PGconn *pg_conn = NULL;
120 PGresult *pg_result = NULL;
126 unsigned int num_fields, num_tuples;
127 uschar *result = NULL;
128 pgsql_connection *cn;
129 uschar *server_copy = NULL;
132 /* Disaggregate the parameters from the server argument. The order is host or
133 path, database, user, password. We can write to the string, since it is in a
134 nextinlist temporary buffer. The copy of the string that is used for caching
135 has the password removed. This copy is also used for debugging output. */
137 for (i = 2; i >= 0; i--)
139 uschar *pp = Ustrrchr(server, '/');
142 *errmsg = string_sprintf("incomplete pgSQL server data: %s",
143 (i == 2)? server : server_copy);
149 if (i == 2) server_copy = string_copy(server); /* sans password */
152 /* The total server string has now been truncated so that what is left at the
153 start is the identification of the server (host or path). See if we have a
154 cached connection to the server. */
156 for (cn = pgsql_connections; cn != NULL; cn = cn->next)
158 if (Ustrcmp(cn->server, server_copy) == 0)
160 pg_conn = cn->handle;
165 /* If there is no cached connection, we must set one up. */
171 /* For a Unix domain socket connection, the path is in parentheses */
175 uschar *last_slash, *last_dot, *p;
178 while (*p != 0 && *p != ')') p++;
181 last_slash = Ustrrchr(server, '/');
182 last_dot = Ustrrchr(server, '.');
184 DEBUG(D_lookup) debug_printf("PGSQL new connection: socket=%s "
185 "database=%s user=%s\n", server, sdata[0], sdata[1]);
187 /* A valid socket name looks like this: /var/run/postgresql/.s.PGSQL.5432
188 We have to call PQsetdbLogin with '/var/run/postgresql' as the hostname
189 argument and put '5432' into the port variable. */
191 if (last_slash == NULL || last_dot == NULL)
193 *errmsg = string_sprintf("PGSQL invalid filename for socket: %s",
199 /* Terminate the path name and set up the port: we'll have something like
200 server = "/var/run/postgresql" and port = "5432". */
206 /* Host connection; sort out the port */
211 if ((p = Ustrchr(server, ':')) != NULL)
217 if (Ustrchr(server, '/') != NULL)
219 *errmsg = string_sprintf("unexpected slash in pgSQL server hostname: %s",
225 DEBUG(D_lookup) debug_printf("PGSQL new connection: host=%s port=%s "
226 "database=%s user=%s\n", server, port, sdata[0], sdata[1]);
229 /* If the database is the empty string, set it NULL - the query must then
232 if (sdata[0][0] == 0) sdata[0] = NULL;
234 /* Get store for a new handle, initialize it, and connect to the server */
236 pg_conn=PQsetdbLogin(
237 /* host port options tty database user passwd */
238 CS server, CS port, NULL, NULL, CS sdata[0], CS sdata[1], CS sdata[2]);
240 if(PQstatus(pg_conn) == CONNECTION_BAD)
242 store_reset(server_copy);
243 *errmsg = string_sprintf("PGSQL connection failed: %s",
244 PQerrorMessage(pg_conn));
246 *defer_break = FALSE;
250 /* Add the connection to the cache */
252 cn = store_get(sizeof(pgsql_connection));
253 cn->server = server_copy;
254 cn->handle = pg_conn;
255 cn->next = pgsql_connections;
256 pgsql_connections = cn;
259 /* Else use a previously cached connection */
263 DEBUG(D_lookup) debug_printf("PGSQL using cached connection for %s\n",
269 pg_result = PQexec(pg_conn, CS query);
270 switch(PQresultStatus(pg_result))
272 case PGRES_EMPTY_QUERY:
273 case PGRES_COMMAND_OK:
274 /* The command was successful but did not return any data since it was
275 * not SELECT but either an INSERT, UPDATE or DELETE statement. Tell the
276 * high level code to not cache this query, and clean the current cache for
277 * this handle by setting *do_cache FALSE. */
278 result = string_copy(US PQcmdTuples(pg_result));
279 offset = Ustrlen(result);
281 DEBUG(D_lookup) debug_printf("PGSQL: command does not return any data "
282 "but was successful. Rows affected: %s\n", result);
284 case PGRES_TUPLES_OK:
288 /* This was the original code:
289 *errmsg = string_sprintf("PGSQL: query failed: %s\n",
290 PQresultErrorMessage(pg_result));
291 This was suggested by a user:
294 *errmsg = string_sprintf("PGSQL: query failed: %s (%s) (%s)\n",
295 PQresultErrorMessage(pg_result),
296 PQresStatus(PQresultStatus(pg_result)), query);
297 *defer_break = FALSE;
301 /* Result is in pg_result. Find the number of fields returned. If this is one,
302 we don't add field names to the data. Otherwise we do. If the query did not
303 return anything we skip the for loop; this also applies to the case
306 num_fields = PQnfields(pg_result);
307 num_tuples = PQntuples(pg_result);
309 /* Get the fields and construct the result string. If there is more than one
310 row, we insert '\n' between them. */
312 for (i = 0; i < num_tuples; i++)
315 result = string_cat(result, &ssize, &offset, US"\n", 1);
319 result = string_cat(result, &ssize, &offset,
320 US PQgetvalue(pg_result, i, 0), PQgetlength(pg_result, i, 0));
326 for (j = 0; j < num_fields; j++)
328 uschar *tmp = US PQgetvalue(pg_result, i, j);
329 result = lf_quote(US PQfname(pg_result, j), tmp, Ustrlen(tmp), result,
335 /* If result is NULL then no data has been found and so we return FAIL.
336 Otherwise, we must terminate the string which has been built; string_cat()
337 always leaves enough room for a terminating zero. */
342 *errmsg = US"PGSQL: no data found";
347 store_reset(result + offset + 1);
350 /* Get here by goto from various error checks. */
354 /* Free store for any result that was got; don't close the connection, as
357 if (pg_result != NULL) PQclear(pg_result);
359 /* Non-NULL result indicates a sucessful result */
368 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
369 return yield; /* FAIL or DEFER */
376 /*************************************************
378 *************************************************/
380 /* See local README for interface description. The handle and filename
381 arguments are not used. Loop through a list of servers while the query is
382 deferred with a retryable error. */
385 pgsql_find(void *handle, uschar *filename, uschar *query, int length,
386 uschar **result, uschar **errmsg, BOOL *do_cache)
390 uschar *list = pgsql_servers;
393 DEBUG(D_lookup) debug_printf("PGSQL query: %s\n", query);
395 while ((server = string_nextinlist(&list, &sep, buffer, sizeof(buffer)))
399 int rc = perform_pgsql_search(query, server, result, errmsg, &defer_break,
401 if (rc != DEFER || defer_break) return rc;
404 if (pgsql_servers == NULL)
405 *errmsg = US"no PGSQL servers defined (pgsql_servers option)";
412 /*************************************************
413 * Quote entry point *
414 *************************************************/
416 /* The characters that always need to be quoted (with backslash) are newline,
417 tab, carriage return, backspace, backslash itself, and the quote characters.
418 Percent and underscore are only special in contexts where they can be wild
419 cards, and this isn't usually the case for data inserted from messages, since
420 that isn't likely to be treated as a pattern of any kind. However, pgsql seems
421 to allow escaping "on spec". If you use something like "where id="ab\%cd" it
422 does treat the string as "ab%cd". So we can safely quote percent and
423 underscore. [This is different to MySQL, where you can't do this.]
426 s the string to be quoted
427 opt additional option text or NULL if none
429 Returns: the processed string or NULL for a bad option
433 pgsql_quote(uschar *s, uschar *opt)
440 if (opt != NULL) return NULL; /* No options recognized */
442 while ((c = *t++) != 0)
443 if (Ustrchr("\n\t\r\b\'\"\\%_", c) != NULL) count++;
445 if (count == 0) return s;
446 t = quoted = store_get(Ustrlen(s) + count + 1);
448 while ((c = *s++) != 0)
450 if (Ustrchr("\n\t\r\b\'\"\\%_", c) != NULL)
455 case '\n': *t++ = 'n';
457 case '\t': *t++ = 't';
459 case '\r': *t++ = 'r';
461 case '\b': *t++ = 'b';
474 #endif /* PGSQL_LOOKUP */
476 /* End of lookups/pgsql.c */