Age Owner Branch data TLA Line data Source code
1 : : /*
2 : : * contrib/spi/insert_username.c
3 : : *
4 : : * insert user name in response to a trigger
5 : : * usage: insert_username (column_name)
6 : : */
7 : : #include "postgres.h"
8 : :
9 : : #include "access/htup_details.h"
10 : : #include "catalog/pg_type.h"
11 : : #include "commands/trigger.h"
12 : : #include "executor/spi.h"
13 : : #include "miscadmin.h"
14 : : #include "utils/builtins.h"
15 : : #include "utils/rel.h"
16 : :
6529 tgl@sss.pgh.pa.us 17 :UBC 0 : PG_MODULE_MAGIC;
18 : :
8546 19 : 0 : PG_FUNCTION_INFO_V1(insert_username);
20 : :
21 : : Datum
8721 22 : 0 : insert_username(PG_FUNCTION_ARGS)
23 : : {
24 : 0 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
25 : : Trigger *trigger; /* to get trigger name */
26 : : int nargs; /* # of arguments */
27 : : Datum newval; /* new value of column */
28 : : bool newnull; /* null flag */
29 : : char **args; /* arguments */
30 : : char *relname; /* triggered relation name */
31 : : Relation rel; /* triggered relation */
9676 vadim4o@yahoo.com 32 : 0 : HeapTuple rettuple = NULL;
33 : : TupleDesc tupdesc; /* tuple description */
34 : : int attnum;
35 : :
36 : : /* sanity checks from autoinc.c */
8721 tgl@sss.pgh.pa.us 37 [ # # # # ]: 0 : if (!CALLED_AS_TRIGGER(fcinfo))
38 : : /* internal error */
39 [ # # ]: 0 : elog(ERROR, "insert_username: not fired by trigger manager");
4937 40 [ # # ]: 0 : if (!TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
41 : : /* internal error */
42 [ # # ]: 0 : elog(ERROR, "insert_username: must be fired for row");
43 [ # # ]: 0 : if (!TRIGGER_FIRED_BEFORE(trigdata->tg_event))
44 : : /* internal error */
9595 bruce@momjian.us 45 [ # # ]: 0 : elog(ERROR, "insert_username: must be fired before event");
46 : :
8721 tgl@sss.pgh.pa.us 47 [ # # ]: 0 : if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
48 : 0 : rettuple = trigdata->tg_trigtuple;
49 [ # # ]: 0 : else if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
50 : 0 : rettuple = trigdata->tg_newtuple;
51 : : else
52 : : /* internal error */
6282 bruce@momjian.us 53 [ # # ]: 0 : elog(ERROR, "insert_username: cannot process DELETE events");
54 : :
8721 tgl@sss.pgh.pa.us 55 : 0 : rel = trigdata->tg_relation;
9676 vadim4o@yahoo.com 56 : 0 : relname = SPI_getrelname(rel);
57 : :
8721 tgl@sss.pgh.pa.us 58 : 0 : trigger = trigdata->tg_trigger;
59 : :
9676 vadim4o@yahoo.com 60 : 0 : nargs = trigger->tgnargs;
61 [ # # ]: 0 : if (nargs != 1)
62 : : /* internal error */
9595 bruce@momjian.us 63 [ # # ]: 0 : elog(ERROR, "insert_username (%s): one argument was expected", relname);
64 : :
9676 vadim4o@yahoo.com 65 : 0 : args = trigger->tgargs;
66 : 0 : tupdesc = rel->rd_att;
67 : :
9544 bruce@momjian.us 68 : 0 : attnum = SPI_fnumber(tupdesc, args[0]);
69 : :
2714 tgl@sss.pgh.pa.us 70 [ # # ]: 0 : if (attnum <= 0)
7570 71 [ # # ]: 0 : ereport(ERROR,
72 : : (errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
73 : : errmsg("\"%s\" has no attribute \"%s\"", relname, args[0])));
74 : :
9544 bruce@momjian.us 75 [ # # ]: 0 : if (SPI_gettypeid(tupdesc, attnum) != TEXTOID)
7570 tgl@sss.pgh.pa.us 76 [ # # ]: 0 : ereport(ERROR,
77 : : (errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
78 : : errmsg("attribute \"%s\" of \"%s\" must be type TEXT",
79 : : args[0], relname)));
80 : :
81 : : /* create fields containing name */
3263 andrew@dunslane.net 82 : 0 : newval = CStringGetTextDatum(GetUserNameFromId(GetUserId(), false));
2714 tgl@sss.pgh.pa.us 83 : 0 : newnull = false;
84 : :
85 : : /* construct new tuple */
86 : 0 : rettuple = heap_modify_tuple_by_cols(rettuple, tupdesc,
87 : : 1, &attnum, &newval, &newnull);
88 : :
9544 bruce@momjian.us 89 : 0 : pfree(relname);
90 : :
8721 tgl@sss.pgh.pa.us 91 : 0 : return PointerGetDatum(rettuple);
92 : : }
|
