@ -1,14 +1,15 @@
/*-------------------------------------------------------------------------
*
* genfile . c
* Functions for direct access to files
*
*
* Copyright ( c ) 2004 , PostgreSQL Global Development Group
* Copyright ( c ) 2004 - 2005 , PostgreSQL Global Development Group
*
* Author : Andreas Pflug < pgadmin @ pse - consulting . de >
*
* IDENTIFICATION
* $ PostgreSQL : pgsql / src / backend / utils / adt / genfile . c , v 1.1 2005 / 08 / 12 03 : 24 : 08 momjian Exp $
* $ PostgreSQL : pgsql / src / backend / utils / adt / genfile . c , v 1.2 2005 / 08 / 12 18 : 23 : 54 tgl Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
@ -19,13 +20,15 @@
# include <unistd.h>
# include <dirent.h>
# include "utils/builtins.h"
# include "miscadmin.h"
# include "storage/fd.h"
# include "access/heapam.h"
# include "catalog/pg_type.h"
# include "funcapi.h"
# include "miscadmin.h"
# include "postmaster/syslogger.h"
# include "storage/fd.h"
# include "utils/builtins.h"
# include "utils/memutils.h"
extern char * Log_directory ;
typedef struct
{
@ -33,13 +36,16 @@ typedef struct
DIR * dirdesc ;
} directory_fctx ;
/*
* Return an absolute path . Argument may be absolute or
* relative to the DataDir .
* Validate a path and convert to absolute form .
*
* Argument may be absolute or relative to the DataDir ( but we only allow
* absolute paths that match Log_directory ) .
*/
static char * check_and_make_absolute ( text * arg )
static char *
check_and_make_absolute ( text * arg )
{
int datadir_len = strlen ( DataDir ) ;
int filename_len = VARSIZE ( arg ) - VARHDRSZ ;
char * filename = palloc ( filename_len + 1 ) ;
@ -52,16 +58,21 @@ static char *check_and_make_absolute(text *arg)
/*
* Prevent reference to the parent directory .
* " ..a.. " is a valid file name though .
*
* XXX this is BROKEN because it fails to prevent " C:.. " on Windows .
* Need access to " skip_drive " functionality to do it right . ( There
* is no actual security hole because we ' ll prepend the DataDir below ,
* resulting in a just - plain - broken path , but we should give the right
* error message instead . )
*/
if ( strcmp ( filename , " .. " ) = = 0 | | /* beginning */
strncmp ( filename , " ../ " , 3 ) = = 0 | | /* beginning */
strcmp ( filename , " /.. " ) = = 0 | | /* beginning */
strncmp ( filename , " ../ " , 3 ) = = 0 | | /* beginning */
strstr ( filename , " /../ " ) ! = NULL | | /* middle */
strncmp ( filename + filename_len - 3 , " /.. " , 3 ) = = 0 ) /* end */
if ( strcmp ( filename , " .. " ) = = 0 | | /* whole */
strncmp ( filename , " ../ " , 3 ) = = 0 | | /* beginning */
strstr ( filename , " /../ " ) ! = NULL | | /* middle */
( filename_len > = 3 & &
strcmp ( filename + filename_len - 3 , " /.. " ) = = 0 ) ) /* end */
ereport ( ERROR ,
( errcode ( ERRCODE_INSUFFICIENT_PRIVILEGE ) ,
( errmsg ( " Reference to a parent directory (\" .. \" ) not allowed " ) ) ) ) ;
( errmsg ( " reference to parent directory (\" .. \" ) not allowed " ) ) ) ) ;
if ( is_absolute_path ( filename ) )
{
@ -74,12 +85,12 @@ static char *check_and_make_absolute(text *arg)
ereport ( ERROR ,
( errcode ( ERRCODE_INSUFFICIENT_PRIVILEGE ) ,
( errmsg ( " Absolute paths not allowed" ) ) ) ) ;
return NULL ;
( errmsg ( " absolute path not allowed" ) ) ) ) ;
return NULL ; /* keep compiler quiet */
}
else
{
char * absname = palloc ( datadir_len + filename_len + 2 ) ;
char * absname = palloc ( strlen ( DataDir ) + filename_len + 2 ) ;
sprintf ( absname , " %s/%s " , DataDir , filename ) ;
pfree ( filename ) ;
return absname ;
@ -87,11 +98,16 @@ static char *check_and_make_absolute(text *arg)
}
Datum pg_read_file ( PG_FUNCTION_ARGS )
/*
* Read a section of a file , returning it as text
*/
Datum
pg_read_file ( PG_FUNCTION_ARGS )
{
int64 bytes_to_read = PG_GETARG_INT64 ( 2 ) ;
text * filename_t = PG_GETARG_TEXT_P ( 0 ) ;
int64 seek_offset = PG_GETARG_INT64 ( 1 ) ;
char * buf = 0 ;
int64 bytes_to_read = PG_GETARG_INT64 ( 2 ) ;
char * buf ;
size_t nbytes ;
FILE * file ;
char * filename ;
@ -101,107 +117,108 @@ Datum pg_read_file(PG_FUNCTION_ARGS)
( errcode ( ERRCODE_INSUFFICIENT_PRIVILEGE ) ,
( errmsg ( " must be superuser to read files " ) ) ) ) ;
filename = check_and_make_absolute ( PG_GETARG_TEXT_P ( 0 ) ) ;
filename = check_and_make_absolute ( filename_t ) ;
if ( ( file = AllocateFile ( filename , PG_BINARY_R ) ) = = NULL )
{
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not open file %s for reading: %m " , filename ) ) ) ;
PG_RETURN_NULL ( ) ;
}
errmsg ( " could not open file \" %s \" for reading: %m " ,
filename ) ) ) ;
if ( fseeko ( file , ( off_t ) seek_offset ,
( seek_offset > = 0 ) ? SEEK_SET : SEEK_END ) ! = 0 )
{
if ( fseeko ( file , ( off_t ) seek_offset ,
( seek_offset > = 0 ) ? SEEK_SET : SEEK_END ) ! = 0 )
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not seek in file %s: %m " , filename ) ) ) ;
PG_RETURN_NULL ( ) ;
}
errmsg ( " could not seek in file \" %s \" : %m " , filename ) ) ) ;
if ( bytes_to_read < 0 )
{
ereport ( ERROR ,
( errcode ( ERRCODE_INVALID_PARAMETER_VALUE ) ,
errmsg ( " length cannot be negative " ) ) ) ;
}
( errcode ( ERRCODE_INVALID_PARAMETER_VALUE ) ,
errmsg ( " requested length cannot be negative " ) ) ) ;
/* not sure why anyone thought that int64 length was a good idea */
if ( bytes_to_read > ( MaxAllocSize - VARHDRSZ ) )
ereport ( ERROR ,
( errcode ( ERRCODE_INVALID_PARAMETER_VALUE ) ,
errmsg ( " requested length too large " ) ) ) ;
buf = palloc ( bytes_to_read + VARHDRSZ ) ;
buf = palloc ( ( Size ) bytes_to_read + VARHDRSZ ) ;
nbytes = fread ( VARDATA ( buf ) , 1 , bytes_to_read , file ) ;
nbytes = fread ( VARDATA ( buf ) , 1 , ( size_t ) bytes_to_read , file ) ;
if ( nbytes < 0 )
{
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not read file %s: %m " , filename ) ) ) ;
PG_RETURN_NULL ( ) ;
}
errmsg ( " could not read file \" %s \" : %m " , filename ) ) ) ;
VARATT_SIZEP ( buf ) = nbytes + VARHDRSZ ;
pfree ( filename ) ;
FreeFile ( file ) ;
pfree ( filename ) ;
PG_RETURN_TEXT_P ( buf ) ;
}
Datum pg_stat_file ( PG_FUNCTION_ARGS )
/*
* stat a file
*/
Datum
pg_stat_file ( PG_FUNCTION_ARGS )
{
AttInMetadata * attinmeta ;
char * filename = check_and_make_absolute ( PG_GETARG_TEXT_P ( 0 ) ) ;
text * filename_t = PG_GETARG_TEXT_P ( 0 ) ;
char * filename ;
struct stat fst ;
char lenbuf [ 30 ] , cbuf [ 30 ] , abuf [ 30 ] , mbuf [ 30 ] , dirbuf [ 2 ] ;
char * values [ 5 ] = { lenbuf , cbuf , abuf , mbuf , dirbuf } ;
pg_time_t timestamp ;
Datum values [ 5 ] ;
bool isnull [ 5 ] ;
HeapTuple tuple ;
TupleDesc tupdesc = CreateTemplateTupleDesc ( 5 , false ) ;
TupleDesc tupdesc ;
if ( ! superuser ( ) )
ereport ( ERROR ,
( errcode ( ERRCODE_INSUFFICIENT_PRIVILEGE ) ,
( errmsg ( " must be superuser to get file information " ) ) ) ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 1 , " length " , INT8OID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 2 , " atime " , TIMESTAMPOID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 3 , " mtime " , TIMESTAMPOID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 4 , " ctime " , TIMESTAMPOID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 5 , " isdir " , BOOLOID , - 1 , 0 ) ;
attinmeta = TupleDescGetAttInMetadata ( tupdesc ) ;
filename = check_and_make_absolute ( filename_t ) ;
if ( stat ( filename , & fst ) < 0 )
{
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not stat file %s: %m " , filename ) ) ) ;
PG_RETURN_NULL ( ) ;
}
else
{
snprintf ( lenbuf , 30 , INT64_FORMAT , ( int64 ) fst . st_size ) ;
timestamp = fst . st_atime ;
pg_strftime ( abuf , 30 , " %F %T " , pg_localtime ( & timestamp , global_timezone ) ) ;
timestamp = fst . st_mtime ;
pg_strftime ( mbuf , 30 , " %F %T " , pg_localtime ( & timestamp , global_timezone ) ) ;
errmsg ( " could not stat file \" %s \" : %m " , filename ) ) ) ;
tupdesc = CreateTemplateTupleDesc ( 5 , false ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 1 ,
" length " , INT8OID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 2 ,
" atime " , TIMESTAMPTZOID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 3 ,
" mtime " , TIMESTAMPTZOID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 4 ,
" ctime " , TIMESTAMPTZOID , - 1 , 0 ) ;
TupleDescInitEntry ( tupdesc , ( AttrNumber ) 5 ,
" isdir " , BOOLOID , - 1 , 0 ) ;
BlessTupleDesc ( tupdesc ) ;
values [ 0 ] = Int64GetDatum ( ( int64 ) fst . st_size ) ;
values [ 1 ] = TimestampTzGetDatum ( time_t_to_timestamptz ( fst . st_atime ) ) ;
values [ 2 ] = TimestampTzGetDatum ( time_t_to_timestamptz ( fst . st_mtime ) ) ;
values [ 3 ] = TimestampTzGetDatum ( time_t_to_timestamptz ( fst . st_ctime ) ) ;
values [ 4 ] = BoolGetDatum ( fst . st_mode & S_IFDIR ) ;
memset ( isnull , false , sizeof ( isnull ) ) ;
tuple = heap_form_tuple ( tupdesc , values , isnull ) ;
timestamp = fst . st_ctime ;
pg_strftime ( cbuf , 30 , " %F %T " , pg_localtime ( & timestamp , global_timezone ) ) ;
if ( fst . st_mode & S_IFDIR )
strcpy ( dirbuf , " t " ) ;
else
strcpy ( dirbuf , " f " ) ;
pfree ( filename ) ;
tuple = BuildTupleFromCStrings ( attinmeta , values ) ;
pfree ( filename ) ;
PG_RETURN_DATUM ( HeapTupleGetDatum ( tuple ) ) ;
}
PG_RETURN_DATUM ( HeapTupleGetDatum ( tuple ) ) ;
}
Datum pg_ls_dir ( PG_FUNCTION_ARGS )
/*
* List a directory ( returns the filenames only )
*/
Datum
pg_ls_dir ( PG_FUNCTION_ARGS )
{
FuncCallContext * funcctx ;
struct dirent * de ;
@ -227,7 +244,8 @@ Datum pg_ls_dir(PG_FUNCTION_ARGS)
if ( ! fctx - > dirdesc )
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " %s is not browsable: %m " , fctx - > location ) ) ) ;
errmsg ( " could not open directory \" %s \" : %m " ,
fctx - > location ) ) ) ;
funcctx - > user_fctx = fctx ;
MemoryContextSwitchTo ( oldcontext ) ;
@ -236,17 +254,16 @@ Datum pg_ls_dir(PG_FUNCTION_ARGS)
funcctx = SRF_PERCALL_SETUP ( ) ;
fctx = ( directory_fctx * ) funcctx - > user_fctx ;
if ( ! fctx - > dirdesc ) /* not a readable directory */
SRF_RETURN_DONE ( funcctx ) ;
while ( ( de = ReadDir ( fctx - > dirdesc , fctx - > location ) ) ! = NULL )
{
int len = strlen ( de - > d_name ) ;
text * result = palloc ( len + VARHDRSZ ) ;
text * result ;
if ( strcmp ( de - > d_name , " . " ) = = 0 | | strcmp ( de - > d_name , " .. " ) = = 0 )
if ( strcmp ( de - > d_name , " . " ) = = 0 | |
strcmp ( de - > d_name , " .. " ) = = 0 )
continue ;
result = palloc ( len + VARHDRSZ ) ;
VARATT_SIZEP ( result ) = len + VARHDRSZ ;
memcpy ( VARDATA ( result ) , de - > d_name , len ) ;
@ -254,5 +271,6 @@ Datum pg_ls_dir(PG_FUNCTION_ARGS)
}
FreeDir ( fctx - > dirdesc ) ;
SRF_RETURN_DONE ( funcctx ) ;
}
Tom Lane
20 years ago