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e7128e8dbb
Because of gcc -Wmissing-prototypes, all functions in dynamically loadable modules must have a separate prototype declaration. This is meant to detect global functions that are not declared in header files, but in cases where the function is called via dfmgr, this is redundant. Besides filling up space with boilerplate, this is a frequent source of compiler warnings in extension modules. We can fix that by creating the function prototype as part of the PG_FUNCTION_INFO_V1 macro, which such modules have to use anyway. That makes the code of modules cleaner, because there is one less place where the entry points have to be listed, and creates an additional check that functions have the right prototype. Remove now redundant prototypes from contrib and other modules.
115 lines
2.7 KiB
C
115 lines
2.7 KiB
C
/*
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* PostgreSQL definitions for managed Large Objects.
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*
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* contrib/lo/lo.c
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*
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*/
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#include "postgres.h"
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#include "commands/trigger.h"
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#include "executor/spi.h"
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#include "libpq/be-fsstubs.h"
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#include "utils/rel.h"
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PG_MODULE_MAGIC;
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#define atooid(x) ((Oid) strtoul((x), NULL, 10))
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/*
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* This is the trigger that protects us from orphaned large objects
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*/
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PG_FUNCTION_INFO_V1(lo_manage);
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Datum
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lo_manage(PG_FUNCTION_ARGS)
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{
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TriggerData *trigdata = (TriggerData *) fcinfo->context;
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int attnum; /* attribute number to monitor */
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char **args; /* Args containing attr name */
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TupleDesc tupdesc; /* Tuple Descriptor */
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HeapTuple rettuple; /* Tuple to be returned */
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bool isdelete; /* are we deleting? */
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HeapTuple newtuple; /* The new value for tuple */
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HeapTuple trigtuple; /* The original value of tuple */
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if (!CALLED_AS_TRIGGER(fcinfo)) /* internal error */
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elog(ERROR, "%s: not fired by trigger manager",
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trigdata->tg_trigger->tgname);
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if (!TRIGGER_FIRED_FOR_ROW(trigdata->tg_event)) /* internal error */
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elog(ERROR, "%s: must be fired for row",
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trigdata->tg_trigger->tgname);
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/*
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* Fetch some values from trigdata
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*/
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newtuple = trigdata->tg_newtuple;
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trigtuple = trigdata->tg_trigtuple;
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tupdesc = trigdata->tg_relation->rd_att;
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args = trigdata->tg_trigger->tgargs;
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if (args == NULL) /* internal error */
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elog(ERROR, "%s: no column name provided in the trigger definition",
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trigdata->tg_trigger->tgname);
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/* tuple to return to Executor */
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if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
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rettuple = newtuple;
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else
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rettuple = trigtuple;
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/* Are we deleting the row? */
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isdelete = TRIGGER_FIRED_BY_DELETE(trigdata->tg_event);
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/* Get the column we're interested in */
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attnum = SPI_fnumber(tupdesc, args[0]);
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if (attnum <= 0)
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elog(ERROR, "%s: column \"%s\" does not exist",
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trigdata->tg_trigger->tgname, args[0]);
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/*
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* Handle updates
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*
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* Here, if the value of the monitored attribute changes, then the large
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* object associated with the original value is unlinked.
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*/
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if (newtuple != NULL)
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{
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char *orig = SPI_getvalue(trigtuple, tupdesc, attnum);
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char *newv = SPI_getvalue(newtuple, tupdesc, attnum);
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if (orig != NULL && (newv == NULL || strcmp(orig, newv) != 0))
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DirectFunctionCall1(lo_unlink,
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ObjectIdGetDatum(atooid(orig)));
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if (newv)
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pfree(newv);
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if (orig)
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pfree(orig);
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}
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/*
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* Handle deleting of rows
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*
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* Here, we unlink the large object associated with the managed attribute
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*/
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if (isdelete)
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{
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char *orig = SPI_getvalue(trigtuple, tupdesc, attnum);
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if (orig != NULL)
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{
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DirectFunctionCall1(lo_unlink,
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ObjectIdGetDatum(atooid(orig)));
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pfree(orig);
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}
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}
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return PointerGetDatum(rettuple);
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}
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