GDAL
Public Member Functions | Static Public Member Functions | Protected Member Functions | List of all members
GDALDriver Class Reference

Format specific driver. More...

#include <gdal_priv.h>

Inheritance diagram for GDALDriver:
GDALMajorObject OGRSFDriver

Public Member Functions

CPLErr SetMetadataItem (const char *pszName, const char *pszValue, const char *pszDomain="") override
 Set single metadata item. More...
 
GDALDatasetCreate (const char *pszName, int nXSize, int nYSize, int nBands, GDALDataType eType, CSLConstList papszOptions)
 Create a new dataset with this driver. More...
 
GDALDatasetCreateMultiDimensional (const char *pszName, CSLConstList papszRootGroupOptions, CSLConstList papszOptions)
 Create a new multidimensional dataset with this driver. More...
 
CPLErr Delete (const char *pszName)
 Delete named dataset. More...
 
CPLErr Rename (const char *pszNewName, const char *pszOldName)
 Rename a dataset. More...
 
CPLErr CopyFiles (const char *pszNewName, const char *pszOldName)
 Copy the files of a dataset. More...
 
GDALDatasetCreateCopy (const char *, GDALDataset *, int, CSLConstList papszOptions, GDALProgressFunc pfnProgress, void *pProgressData)
 Create a copy of a dataset. More...
 
int GetMOFlags () const
 Returns the GMO_ flags. More...
 
void SetMOFlags (int nFlagsIn)
 Assign GMO_flags. More...
 
virtual const char * GetDescription () const
 Fetch object description. More...
 
virtual void SetDescription (const char *)
 Set object description. More...
 
virtual char ** GetMetadataDomainList ()
 Fetch list of metadata domains. More...
 
virtual char ** GetMetadata (const char *pszDomain="")
 Fetch metadata. More...
 
virtual CPLErr SetMetadata (char **papszMetadata, const char *pszDomain="")
 Set metadata. More...
 
virtual const char * GetMetadataItem (const char *pszName, const char *pszDomain="")
 Fetch single metadata item. More...
 

Static Public Member Functions

static CPLErr QuietDelete (const char *pszName, CSLConstList papszAllowedDrivers=nullptr)
 Delete dataset if found. More...
 
static GDALDriverH ToHandle (GDALDriver *poDriver)
 Convert a GDALDriver* to a GDALDriverH. More...
 
static GDALDriverFromHandle (GDALDriverH hDriver)
 Convert a GDALDriverH to a GDALDriver*. More...
 
static GDALMajorObjectH ToHandle (GDALMajorObject *poMajorObject)
 Convert a GDALMajorObject* to a GDALMajorObjectH. More...
 

Protected Member Functions

char ** BuildMetadataDomainList (char **papszList, int bCheckNonEmpty,...) CPL_NULL_TERMINATED
 Helper function for custom implementations of GetMetadataDomainList() More...
 

Detailed Description

Format specific driver.

An instance of this class is created for each supported format, and manages information about the format.

This roughly corresponds to a file format, though some drivers may be gateways to many formats through a secondary multi-library.

Member Function Documentation

◆ BuildMetadataDomainList()

char ** GDALMajorObject::BuildMetadataDomainList ( char **  papszList,
int  bCheckNonEmpty,
  ... 
)
protectedinherited

Helper function for custom implementations of GetMetadataDomainList()

Parameters
papszListinitial list of domains. May be NULL. Will become invalid after function call (use return value)
bCheckNonEmptyif TRUE, each candidate domain will be tested to be non empty
...NULL terminated variadic list of candidate domains.
Returns
NULL or a string list. Must be freed with CSLDestroy()
Since
GDAL 1.11

◆ CopyFiles()

CPLErr GDALDriver::CopyFiles ( const char *  pszNewName,
const char *  pszOldName 
)

Copy the files of a dataset.

Copy all the files associated with a dataset.

Equivalent of the C function GDALCopyDatasetFiles().

Parameters
pszNewNamenew name for the dataset.
pszOldNameold name for the dataset.
Returns
CE_None on success, or CE_Failure if the operation fails.

◆ Create()

GDALDataset * GDALDriver::Create ( const char *  pszFilename,
int  nXSize,
int  nYSize,
int  nBands,
GDALDataType  eType,
CSLConstList  papszOptions 
)

Create a new dataset with this driver.

What argument values are legal for particular drivers is driver specific, and there is no way to query in advance to establish legal values.

That function will try to validate the creation option list passed to the driver with the GDALValidateCreationOptions() method. This check can be disabled by defining the configuration option GDAL_VALIDATE_CREATION_OPTIONS=NO.

After you have finished working with the returned dataset, it is required to close it with GDALClose(). This does not only close the file handle, but also ensures that all the data and metadata has been written to the dataset (GDALFlushCache() is not sufficient for that purpose).

In GDAL 2, the arguments nXSize, nYSize and nBands can be passed to 0 when creating a vector-only dataset for a compatible driver.

Equivalent of the C function GDALCreate().

Parameters
pszFilenamethe name of the dataset to create. UTF-8 encoded.
nXSizewidth of created raster in pixels.
nYSizeheight of created raster in pixels.
nBandsnumber of bands.
eTypetype of raster.
papszOptionslist of driver specific control parameters. The APPEND_SUBDATASET=YES option can be specified to avoid prior destruction of existing dataset.
Returns
NULL on failure, or a new GDALDataset.

◆ CreateCopy()

GDALDataset * GDALDriver::CreateCopy ( const char *  pszFilename,
GDALDataset poSrcDS,
int  bStrict,
CSLConstList  papszOptions,
GDALProgressFunc  pfnProgress,
void *  pProgressData 
)

Create a copy of a dataset.

This method will attempt to create a copy of a raster dataset with the indicated filename, and in this drivers format. Band number, size, type, projection, geotransform and so forth are all to be copied from the provided template dataset.

Note that many sequential write once formats (such as JPEG and PNG) don't implement the Create() method but do implement this CreateCopy() method. If the driver doesn't implement CreateCopy(), but does implement Create() then the default CreateCopy() mechanism built on calling Create() will be used. So to test if CreateCopy() is available, you can test if GDAL_DCAP_CREATECOPY or GDAL_DCAP_CREATE is set in the GDAL metadata.

It is intended that CreateCopy() will often be used with a source dataset which is a virtual dataset allowing configuration of band types, and other information without actually duplicating raster data (see the VRT driver). This is what is done by the gdal_translate utility for example.

That function will try to validate the creation option list passed to the driver with the GDALValidateCreationOptions() method. This check can be disabled by defining the configuration option GDAL_VALIDATE_CREATION_OPTIONS=NO.

This function copy all metadata from the default domain ("")

Even is bStrict is TRUE, only the value of the data is equivalent, but the data layout (INTERLEAVE as PIXEL/LINE/BAND) of the dst dataset is controlled by the papszOptions creation options, and may differ from the poSrcDS src dataset. Starting from GDAL 3.5, if no INTERLEAVE and COMPRESS creation option has been specified in papszOptions, and if the driver supports equivalent interleaving as the src dataset, the CreateCopy() will internally add the proper creation option to get the same data interleaving.

After you have finished working with the returned dataset, it is required to close it with GDALClose(). This does not only close the file handle, but also ensures that all the data and metadata has been written to the dataset (GDALFlushCache() is not sufficient for that purpose).

For multidimensional datasets, papszOptions can contain array creation options, if they are prefixed with "ARRAY:".

See also
GDALGroup::CopyFrom() documentation for further details regarding such options.
Parameters
pszFilenamethe name for the new dataset. UTF-8 encoded.
poSrcDSthe dataset being duplicated.
bStrictTRUE if the copy must be strictly equivalent, or more normally FALSE indicating that the copy may adapt as needed for the output format.
papszOptionsadditional format dependent options controlling creation of the output file. The APPEND_SUBDATASET=YES option can be specified to avoid prior destruction of existing dataset.
pfnProgressa function to be used to report progress of the copy.
pProgressDataapplication data passed into progress function.
Returns
a pointer to the newly created dataset (may be read-only access).

◆ CreateMultiDimensional()

GDALDataset * GDALDriver::CreateMultiDimensional ( const char *  pszFilename,
CSLConstList  papszRootGroupOptions,
CSLConstList  papszOptions 
)

Create a new multidimensional dataset with this driver.

Only drivers that advertise the GDAL_DCAP_MULTIDIM_RASTER capability and implement the pfnCreateMultiDimensional method might return a non nullptr GDALDataset.

This is the same as the C function GDALCreateMultiDimensional().

Parameters
pszFilenamethe name of the dataset to create. UTF-8 encoded.
papszRootGroupOptionsdriver specific options regarding the creation of the root group. Might be nullptr.
papszOptionsdriver specific options regarding the creation of the dataset. Might be nullptr.
Returns
a new dataset, or nullptr in case of failure.
Since
GDAL 3.1

◆ Delete()

CPLErr GDALDriver::Delete ( const char *  pszFilename)

Delete named dataset.

The driver will attempt to delete the named dataset in a driver specific fashion. Full featured drivers will delete all associated files, database objects, or whatever is appropriate. The default behavior when no driver specific behavior is provided is to attempt to delete all the files that are returned by GDALGetFileList() on the dataset handle.

It is unwise to have open dataset handles on this dataset when it is deleted.

Equivalent of the C function GDALDeleteDataset().

Parameters
pszFilenamename of dataset to delete.
Returns
CE_None on success, or CE_Failure if the operation fails.

◆ FromHandle()

static GDALDriver * GDALDriver::FromHandle ( GDALDriverH  hDriver)
inlinestatic

Convert a GDALDriverH to a GDALDriver*.

Since
GDAL 2.3

◆ GetDescription()

const char * GDALMajorObject::GetDescription ( ) const
virtualinherited

Fetch object description.

The semantics of the returned description are specific to the derived type. For GDALDatasets it is the dataset name. For GDALRasterBands it is actually a description (if supported) or "".

This method is the same as the C function GDALGetDescription().

Returns
non-null pointer to internal description string.

◆ GetMetadata()

char ** GDALMajorObject::GetMetadata ( const char *  pszDomain = "")
virtualinherited

Fetch metadata.

The returned string list is owned by the object, and may change at any time. It is formatted as a "Name=value" list with the last pointer value being NULL. Use the CPL StringList functions such as CSLFetchNameValue() to manipulate it.

Note that relatively few formats return any metadata at this time.

This method does the same thing as the C function GDALGetMetadata().

Parameters
pszDomainthe domain of interest. Use "" or NULL for the default domain.
Returns
NULL or a string list.

Reimplemented in GDALPamDataset, and GDALDataset.

◆ GetMetadataDomainList()

char ** GDALMajorObject::GetMetadataDomainList ( )
virtualinherited

Fetch list of metadata domains.

The returned string list is the list of (non-empty) metadata domains.

This method does the same thing as the C function GDALGetMetadataDomainList().

Returns
NULL or a string list. Must be freed with CSLDestroy()
Since
GDAL 1.11

Reimplemented in GDALDataset.

◆ GetMetadataItem()

const char * GDALMajorObject::GetMetadataItem ( const char *  pszName,
const char *  pszDomain = "" 
)
virtualinherited

Fetch single metadata item.

The C function GDALGetMetadataItem() does the same thing as this method.

Parameters
pszNamethe key for the metadata item to fetch.
pszDomainthe domain to fetch for, use NULL for the default domain.
Returns
NULL on failure to find the key, or a pointer to an internal copy of the value string on success.

Reimplemented in GDALPamDataset.

◆ GetMOFlags()

int GDALMajorObject::GetMOFlags ( ) const
inherited

Returns the GMO_ flags.

Returns
flags

◆ QuietDelete()

CPLErr GDALDriver::QuietDelete ( const char *  pszName,
CSLConstList  papszAllowedDrivers = nullptr 
)
static

Delete dataset if found.

This is a helper method primarily used by Create() and CreateCopy() to predelete any dataset of the name soon to be created. It will attempt to delete the named dataset if one is found, otherwise it does nothing. An error is only returned if the dataset is found but the delete fails.

This is a static method and it doesn't matter what driver instance it is invoked on. It will attempt to discover the correct driver using Identify().

Parameters
pszNamethe dataset name to try and delete.
papszAllowedDriversNULL to consider all candidate drivers, or a NULL terminated list of strings with the driver short names that must be considered. (Note: implemented only starting with GDAL 3.4.1)
Returns
CE_None if the dataset does not exist, or is deleted without issues.

◆ Rename()

CPLErr GDALDriver::Rename ( const char *  pszNewName,
const char *  pszOldName 
)

Rename a dataset.

Rename a dataset. This may including moving the dataset to a new directory or even a new filesystem.

It is unwise to have open dataset handles on this dataset when it is being renamed.

Equivalent of the C function GDALRenameDataset().

Parameters
pszNewNamenew name for the dataset.
pszOldNameold name for the dataset.
Returns
CE_None on success, or CE_Failure if the operation fails.

◆ SetDescription()

void GDALMajorObject::SetDescription ( const char *  pszNewDesc)
virtualinherited

Set object description.

The semantics of the description are specific to the derived type. For GDALDatasets it is the dataset name. For GDALRasterBands it is actually a description (if supported) or "".

Normally application code should not set the "description" for GDALDatasets. It is handled internally.

This method is the same as the C function GDALSetDescription().

Reimplemented in GDALPamRasterBand.

◆ SetMetadata()

CPLErr GDALMajorObject::SetMetadata ( char **  papszMetadataIn,
const char *  pszDomain = "" 
)
virtualinherited

Set metadata.

The C function GDALSetMetadata() does the same thing as this method.

Parameters
papszMetadataInthe metadata in name=value string list format to apply.
pszDomainthe domain of interest. Use "" or NULL for the default domain.
Returns
CE_None on success, CE_Failure on failure and CE_Warning if the metadata has been accepted, but is likely not maintained persistently by the underlying object between sessions.

Reimplemented in GDALDataset, GDALRasterBand, GDALPamDataset, and GDALPamRasterBand.

◆ SetMetadataItem()

CPLErr GDALDriver::SetMetadataItem ( const char *  pszName,
const char *  pszValue,
const char *  pszDomain = "" 
)
overridevirtual

Set single metadata item.

The C function GDALSetMetadataItem() does the same thing as this method.

Parameters
pszNamethe key for the metadata item to fetch.
pszValuethe value to assign to the key.
pszDomainthe domain to set within, use NULL for the default domain.
Returns
CE_None on success, or an error code on failure.

Reimplemented from GDALMajorObject.

◆ SetMOFlags()

void GDALMajorObject::SetMOFlags ( int  nNewFlags)
inherited

Assign GMO_flags.

Parameters
nNewFlagsnew flags.

◆ ToHandle() [1/2]

static GDALDriverH GDALDriver::ToHandle ( GDALDriver poDriver)
inlinestatic

Convert a GDALDriver* to a GDALDriverH.

Since
GDAL 2.3

◆ ToHandle() [2/2]

static GDALMajorObjectH GDALMajorObject::ToHandle ( GDALMajorObject poMajorObject)
inlinestaticinherited

Convert a GDALMajorObject* to a GDALMajorObjectH.

Since
GDAL 2.3

The documentation for this class was generated from the following files: