#include "postgres.h"
#include "access/reloptions.h"
#include "catalog/pg_foreign_server.h"
#include "catalog/pg_foreign_table.h"
#include "catalog/pg_user_mapping.h"
#include "commands/defrem.h"
#include "commands/extension.h"
#include "libpq/libpq-be.h"
#include "postgres_fdw.h"
#include "utils/builtins.h"
#include "utils/guc.h"
#include "utils/varlena.h"
#include "miscadmin.h"

Include dependency graph for option.c:

Data Structures
struct	PgFdwOption

Typedefs
typedef struct PgFdwOption	PgFdwOption

Functions
void	_PG_init (void)

static void	InitPgFdwOptions (void)

static bool	is_valid_option (const char *keyword, Oid context)

static bool	is_libpq_option (const char *keyword)

	PG_FUNCTION_INFO_V1 (postgres_fdw_validator)

Datum	postgres_fdw_validator (PG_FUNCTION_ARGS)

int	ExtractConnectionOptions (List defelems, const char keywords, const char *values)

List *	ExtractExtensionList (const char *extensionsString, bool warnOnMissing)

char *	process_pgfdw_appname (const char *appname)

Variables
static PgFdwOption *	postgres_fdw_options

static PQconninfoOption *	libpq_options

char *	pgfdw_application_name = NULL

Typedef Documentation

◆ PgFdwOption

typedef struct PgFdwOption PgFdwOption

Function Documentation

◆ _PG_init()

void _PG_init ( void )

Definition at line 514 of file option.c.

 {
     /*
      * Unlike application_name GUC, don't set GUC_IS_NAME flag nor check_hook
      * to allow postgres_fdw.application_name to be any string more than
      * NAMEDATALEN characters and to include non-ASCII characters. Instead,
      * remote server truncates application_name of remote connection to less
      * than NAMEDATALEN and replaces any non-ASCII characters in it with a '?'
      * character.
      */
     DefineCustomStringVariable("postgres_fdw.application_name",
                                "Sets the application name to be used on the remote server.",
                                NULL,
                                &pgfdw_application_name,
                                NULL,
                                PGC_USERSET,
                                0,
                                NULL,
                                NULL,
                                NULL);
  
     EmitWarningsOnPlaceholders("postgres_fdw");
 }

References DefineCustomStringVariable(), EmitWarningsOnPlaceholders(), PGC_USERSET, and pgfdw_application_name.

◆ ExtractConnectionOptions()

int ExtractConnectionOptions	(	List *	defelems,
		const char **	keywords,
		const char **	values
	)

Definition at line 380 of file option.c.

 {
     ListCell   *lc;
     int         i;
  
     /* Build our options lists if we didn't yet. */
     InitPgFdwOptions();
  
     i = 0;
     foreach(lc, defelems)
     {
         DefElem    *d = (DefElem *) lfirst(lc);
  
         if (is_libpq_option(d->defname))
         {
             keywords[i] = d->defname;
             values[i] = defGetString(d);
             i++;
         }
     }
     return i;
 }

References defGetString(), DefElem::defname, i, InitPgFdwOptions(), is_libpq_option(), lfirst, and values.

Referenced by connect_pg_server().

◆ ExtractExtensionList()

List* ExtractExtensionList	(	const char *	extensionsString,
		bool	warnOnMissing
	)

Definition at line 411 of file option.c.

 {
     List       *extensionOids = NIL;
     List       *extlist;
     ListCell   *lc;
  
     /* SplitIdentifierString scribbles on its input, so pstrdup first */
     if (!SplitIdentifierString(pstrdup(extensionsString), ',', &extlist))
     {
         /* syntax error in name list */
         ereport(ERROR,
                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                  errmsg("parameter \"%s\" must be a list of extension names",
                         "extensions")));
     }
  
     foreach(lc, extlist)
     {
         const char *extension_name = (const char *) lfirst(lc);
         Oid         extension_oid = get_extension_oid(extension_name, true);
  
         if (OidIsValid(extension_oid))
         {
             extensionOids = lappend_oid(extensionOids, extension_oid);
         }
         else if (warnOnMissing)
         {
             ereport(WARNING,
                     (errcode(ERRCODE_UNDEFINED_OBJECT),
                      errmsg("extension \"%s\" is not installed",
                             extension_name)));
         }
     }
  
     list_free(extlist);
     return extensionOids;
 }

References ereport, errcode(), errmsg(), ERROR, get_extension_oid(), lappend_oid(), lfirst, list_free(), NIL, OidIsValid, pstrdup(), SplitIdentifierString(), and WARNING.

Referenced by apply_server_options(), and postgres_fdw_validator().

◆ InitPgFdwOptions()

static void InitPgFdwOptions ( void )

static

Definition at line 218 of file option.c.

 {
     int         num_libpq_opts;
     PQconninfoOption *lopt;
     PgFdwOption *popt;
  
     /* non-libpq FDW-specific FDW options */
     static const PgFdwOption non_libpq_options[] = {
         {"schema_name", ForeignTableRelationId, false},
         {"table_name", ForeignTableRelationId, false},
         {"column_name", AttributeRelationId, false},
         /* use_remote_estimate is available on both server and table */
         {"use_remote_estimate", ForeignServerRelationId, false},
         {"use_remote_estimate", ForeignTableRelationId, false},
         /* cost factors */
         {"fdw_startup_cost", ForeignServerRelationId, false},
         {"fdw_tuple_cost", ForeignServerRelationId, false},
         /* shippable extensions */
         {"extensions", ForeignServerRelationId, false},
         /* updatable is available on both server and table */
         {"updatable", ForeignServerRelationId, false},
         {"updatable", ForeignTableRelationId, false},
         /* truncatable is available on both server and table */
         {"truncatable", ForeignServerRelationId, false},
         {"truncatable", ForeignTableRelationId, false},
         /* fetch_size is available on both server and table */
         {"fetch_size", ForeignServerRelationId, false},
         {"fetch_size", ForeignTableRelationId, false},
         /* batch_size is available on both server and table */
         {"batch_size", ForeignServerRelationId, false},
         {"batch_size", ForeignTableRelationId, false},
         /* async_capable is available on both server and table */
         {"async_capable", ForeignServerRelationId, false},
         {"async_capable", ForeignTableRelationId, false},
         {"keep_connections", ForeignServerRelationId, false},
         {"password_required", UserMappingRelationId, false},
  
         /*
          * sslcert and sslkey are in fact libpq options, but we repeat them
          * here to allow them to appear in both foreign server context (when
          * we generate libpq options) and user mapping context (from here).
          */
         {"sslcert", UserMappingRelationId, true},
         {"sslkey", UserMappingRelationId, true},
  
         {NULL, InvalidOid, false}
     };
  
     /* Prevent redundant initialization. */
     if (postgres_fdw_options)
         return;
  
     /*
      * Get list of valid libpq options.
      *
      * To avoid unnecessary work, we get the list once and use it throughout
      * the lifetime of this backend process.  We don't need to care about
      * memory context issues, because PQconndefaults allocates with malloc.
      */
     libpq_options = PQconndefaults();
     if (!libpq_options)         /* assume reason for failure is OOM */
         ereport(ERROR,
                 (errcode(ERRCODE_FDW_OUT_OF_MEMORY),
                  errmsg("out of memory"),
                  errdetail("Could not get libpq's default connection options.")));
  
     /* Count how many libpq options are available. */
     num_libpq_opts = 0;
     for (lopt = libpq_options; lopt->keyword; lopt++)
         num_libpq_opts++;
  
     /*
      * Construct an array which consists of all valid options for
      * postgres_fdw, by appending FDW-specific options to libpq options.
      *
      * We use plain malloc here to allocate postgres_fdw_options because it
      * lives as long as the backend process does.  Besides, keeping
      * libpq_options in memory allows us to avoid copying every keyword
      * string.
      */
     postgres_fdw_options = (PgFdwOption *)
         malloc(sizeof(PgFdwOption) * num_libpq_opts +
                sizeof(non_libpq_options));
     if (postgres_fdw_options == NULL)
         ereport(ERROR,
                 (errcode(ERRCODE_FDW_OUT_OF_MEMORY),
                  errmsg("out of memory")));
  
     popt = postgres_fdw_options;
     for (lopt = libpq_options; lopt->keyword; lopt++)
     {
         /* Hide debug options, as well as settings we override internally. */
         if (strchr(lopt->dispchar, 'D') ||
             strcmp(lopt->keyword, "fallback_application_name") == 0 ||
             strcmp(lopt->keyword, "client_encoding") == 0)
             continue;
  
         /* We don't have to copy keyword string, as described above. */
         popt->keyword = lopt->keyword;
  
         /*
          * "user" and any secret options are allowed only on user mappings.
          * Everything else is a server option.
          */
         if (strcmp(lopt->keyword, "user") == 0 || strchr(lopt->dispchar, '*'))
             popt->optcontext = UserMappingRelationId;
         else
             popt->optcontext = ForeignServerRelationId;
         popt->is_libpq_opt = true;
  
         popt++;
     }
  
     /* Append FDW-specific options and dummy terminator. */
     memcpy(popt, non_libpq_options, sizeof(non_libpq_options));
 }

References _PQconninfoOption::dispchar, ereport, errcode(), errdetail(), errmsg(), ERROR, InvalidOid, PgFdwOption::is_libpq_opt, PgFdwOption::keyword, _PQconninfoOption::keyword, libpq_options, malloc, PgFdwOption::optcontext, postgres_fdw_options, and PQconndefaults().

Referenced by ExtractConnectionOptions(), and postgres_fdw_validator().

◆ is_libpq_option()

static bool is_libpq_option ( const char * keyword )

static

Definition at line 359 of file option.c.

 {
     PgFdwOption *opt;
  
     Assert(postgres_fdw_options);   /* must be initialized already */
  
     for (opt = postgres_fdw_options; opt->keyword; opt++)
     {
         if (opt->is_libpq_opt && strcmp(opt->keyword, keyword) == 0)
             return true;
     }
  
     return false;
 }

References Assert(), PgFdwOption::is_libpq_opt, PgFdwOption::keyword, and postgres_fdw_options.

Referenced by ExtractConnectionOptions().

◆ is_valid_option()

static bool is_valid_option	(	const char *	keyword,
		Oid	context
	)

static

Definition at line 340 of file option.c.

 {
     PgFdwOption *opt;
  
     Assert(postgres_fdw_options);   /* must be initialized already */
  
     for (opt = postgres_fdw_options; opt->keyword; opt++)
     {
         if (context == opt->optcontext && strcmp(opt->keyword, keyword) == 0)
             return true;
     }
  
     return false;
 }

References Assert(), PgFdwOption::keyword, PgFdwOption::optcontext, and postgres_fdw_options.

Referenced by postgres_fdw_validator().

◆ PG_FUNCTION_INFO_V1()

PG_FUNCTION_INFO_V1 ( postgres_fdw_validator )

◆ postgres_fdw_validator()

Datum postgres_fdw_validator ( PG_FUNCTION_ARGS )

Definition at line 74 of file option.c.

 {
     List       *options_list = untransformRelOptions(PG_GETARG_DATUM(0));
     Oid         catalog = PG_GETARG_OID(1);
     ListCell   *cell;
  
     /* Build our options lists if we didn't yet. */
     InitPgFdwOptions();
  
     /*
      * Check that only options supported by postgres_fdw, and allowed for the
      * current object type, are given.
      */
     foreach(cell, options_list)
     {
         DefElem    *def = (DefElem *) lfirst(cell);
  
         if (!is_valid_option(def->defname, catalog))
         {
             /*
              * Unknown option specified, complain about it. Provide a hint
              * with list of valid options for the object.
              */
             PgFdwOption *opt;
             StringInfoData buf;
  
             initStringInfo(&buf);
             for (opt = postgres_fdw_options; opt->keyword; opt++)
             {
                 if (catalog == opt->optcontext)
                     appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
                                      opt->keyword);
             }
  
             ereport(ERROR,
                     (errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
                      errmsg("invalid option \"%s\"", def->defname),
                      buf.len > 0
                      ? errhint("Valid options in this context are: %s",
                                buf.data)
                      : errhint("There are no valid options in this context.")));
         }
  
         /*
          * Validate option value, when we can do so without any context.
          */
         if (strcmp(def->defname, "use_remote_estimate") == 0 ||
             strcmp(def->defname, "updatable") == 0 ||
             strcmp(def->defname, "truncatable") == 0 ||
             strcmp(def->defname, "async_capable") == 0 ||
             strcmp(def->defname, "keep_connections") == 0)
         {
             /* these accept only boolean values */
             (void) defGetBoolean(def);
         }
         else if (strcmp(def->defname, "fdw_startup_cost") == 0 ||
                  strcmp(def->defname, "fdw_tuple_cost") == 0)
         {
             /*
              * These must have a floating point value greater than or equal to
              * zero.
              */
             char       *value;
             double      real_val;
             bool        is_parsed;
  
             value = defGetString(def);
             is_parsed = parse_real(value, &real_val, 0, NULL);
  
             if (!is_parsed)
                 ereport(ERROR,
                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                          errmsg("invalid value for floating point option \"%s\": %s",
                                 def->defname, value)));
  
             if (real_val < 0)
                 ereport(ERROR,
                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                          errmsg("\"%s\" must be a floating point value greater than or equal to zero",
                                 def->defname)));
         }
         else if (strcmp(def->defname, "extensions") == 0)
         {
             /* check list syntax, warn about uninstalled extensions */
             (void) ExtractExtensionList(defGetString(def), true);
         }
         else if (strcmp(def->defname, "fetch_size") == 0 ||
                  strcmp(def->defname, "batch_size") == 0)
         {
             char       *value;
             int         int_val;
             bool        is_parsed;
  
             value = defGetString(def);
             is_parsed = parse_int(value, &int_val, 0, NULL);
  
             if (!is_parsed)
                 ereport(ERROR,
                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                          errmsg("invalid value for integer option \"%s\": %s",
                                 def->defname, value)));
  
             if (int_val <= 0)
                 ereport(ERROR,
                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                          errmsg("\"%s\" must be an integer value greater than zero",
                                 def->defname)));
         }
         else if (strcmp(def->defname, "password_required") == 0)
         {
             bool        pw_required = defGetBoolean(def);
  
             /*
              * Only the superuser may set this option on a user mapping, or
              * alter a user mapping on which this option is set. We allow a
              * user to clear this option if it's set - in fact, we don't have
              * a choice since we can't see the old mapping when validating an
              * alter.
              */
             if (!superuser() && !pw_required)
                 ereport(ERROR,
                         (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                          errmsg("password_required=false is superuser-only"),
                          errhint("User mappings with the password_required option set to false may only be created or modified by the superuser")));
         }
         else if (strcmp(def->defname, "sslcert") == 0 ||
                  strcmp(def->defname, "sslkey") == 0)
         {
             /* similarly for sslcert / sslkey on user mapping */
             if (catalog == UserMappingRelationId && !superuser())
                 ereport(ERROR,
                         (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                          errmsg("sslcert and sslkey are superuser-only"),
                          errhint("User mappings with the sslcert or sslkey options set may only be created or modified by the superuser")));
         }
     }
  
     PG_RETURN_VOID();
 }

References appendStringInfo(), buf, defGetBoolean(), defGetString(), DefElem::defname, ereport, errcode(), errhint(), errmsg(), ERROR, ExtractExtensionList(), InitPgFdwOptions(), initStringInfo(), is_valid_option(), PgFdwOption::keyword, lfirst, PgFdwOption::optcontext, parse_int(), parse_real(), PG_GETARG_DATUM, PG_GETARG_OID, PG_RETURN_VOID, postgres_fdw_options, superuser(), untransformRelOptions(), and value.

◆ process_pgfdw_appname()

char* process_pgfdw_appname ( const char * appname )

Definition at line 457 of file option.c.

 {
     const char *p;
     StringInfoData buf;
  
     Assert(MyProcPort != NULL);
  
     initStringInfo(&buf);
  
     for (p = appname; *p != '\0'; p++)
     {
         if (*p != '%')
         {
             /* literal char, just copy */
             appendStringInfoChar(&buf, *p);
             continue;
         }
  
         /* must be a '%', so skip to the next char */
         p++;
         if (*p == '\0')
             break;              /* format error - ignore it */
         else if (*p == '%')
         {
             /* string contains %% */
             appendStringInfoChar(&buf, '%');
             continue;
         }
  
         /* process the option */
         switch (*p)
         {
             case 'a':
                 appendStringInfoString(&buf, application_name);
                 break;
             case 'd':
                 appendStringInfoString(&buf, MyProcPort->database_name);
                 break;
             case 'p':
                 appendStringInfo(&buf, "%d", MyProcPid);
                 break;
             case 'u':
                 appendStringInfoString(&buf, MyProcPort->user_name);
                 break;
             default:
                 /* format error - ignore it */
                 break;
         }
     }
  
     return buf.data;
 }