#include <stdio.h>
#include <stdlib.h>
-#include "data/dataset-reader.h"
+#include "data/casereader.h"
+#include "data/dataset.h"
+#include "data/dictionary.h"
#include "data/file-handle-def.h"
#include "data/file-name.h"
-#include "data/por-file-reader.h"
-#include "data/sys-file-reader.h"
#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
#include "libpspp/message.h"
#include "libpspp/str.h"
#include "gettext.h"
#define _(msgid) gettext (msgid)
+#define N_(msgid) (msgid)
-/* Tries to detect whether FILE is a given type of file, by opening the file
- and passing it to DETECT, and returns a detect_result. */
-static enum detect_result
-try_detect (const char *file_name, bool (*detect) (FILE *))
+static const struct any_reader_class dataset_reader_class;
+
+static const struct any_reader_class *classes[] =
+ {
+ &sys_file_reader_class,
+ &por_file_reader_class,
+ &pcp_file_reader_class,
+ };
+enum { N_CLASSES = sizeof classes / sizeof *classes };
+
+int
+any_reader_detect (const char *file_name,
+ const struct any_reader_class **classp)
{
+ struct detector
+ {
+ enum any_type type;
+ int (*detect) (FILE *);
+ };
+
FILE *file;
- bool is_type;
+ int retval;
+
+ if (classp)
+ *classp = NULL;
file = fn_open (file_name, "rb");
if (file == NULL)
{
msg (ME, _("An error occurred while opening `%s': %s."),
file_name, strerror (errno));
- return ANY_ERROR;
+ return -errno;
}
- is_type = detect (file);
-
- fn_close (file_name, file);
+ retval = 0;
+ for (int i = 0; i < N_CLASSES; i++)
+ {
+ int rc = classes[i]->detect (file);
+ if (rc == 1)
+ {
+ retval = 1;
+ if (classp)
+ *classp = classes[i];
+ break;
+ }
+ else if (rc < 0)
+ retval = rc;
+ }
- return is_type ? ANY_YES : ANY_NO;
-}
+ if (retval < 0)
+ msg (ME, _("Error reading `%s': %s."), file_name, strerror (-retval));
-/* Returns true if any_reader_open() would be able to open FILE as a data
- file, false otherwise. */
-enum detect_result
-any_reader_may_open (const char *file)
-{
- enum detect_result res = try_detect (file, sfm_detect);
-
- if (res == ANY_NO)
- res = try_detect (file, pfm_detect);
+ fn_close (file_name, file);
- return res;
+ return retval;
}
-/* Returns a casereader for HANDLE. On success, returns the new
- casereader and stores the file's dictionary into *DICT. On
- failure, returns a null pointer.
-
- Ordinarily the reader attempts to automatically detect the character
- encoding based on the file's contents. This isn't always possible,
- especially for files written by old versions of SPSS or PSPP, so specifying
- a nonnull ENCODING overrides the choice of character encoding. */
-struct casereader *
-any_reader_open (struct file_handle *handle, const char *encoding,
- struct dictionary **dict)
+struct any_reader *
+any_reader_open (struct file_handle *handle)
{
switch (fh_get_referent (handle))
{
case FH_REF_FILE:
{
- enum detect_result result;
+ const struct any_reader_class *class;
+ int retval;
- result = try_detect (fh_get_file_name (handle), sfm_detect);
- if (result == ANY_ERROR)
- return NULL;
- else if (result == ANY_YES)
+ retval = any_reader_detect (fh_get_file_name (handle), &class);
+ if (retval <= 0)
{
- struct sfm_reader *r;
-
- r = sfm_open (handle);
- if (r == NULL)
- return NULL;
-
- return sfm_decode (r, encoding, dict, NULL);
+ if (retval == 0)
+ msg (SE, _("`%s' is not a system or portable file."),
+ fh_get_file_name (handle));
+ return NULL;
}
- result = try_detect (fh_get_file_name (handle), pfm_detect);
- if (result == ANY_ERROR)
- return NULL;
- else if (result == ANY_YES)
- return pfm_open_reader (handle, dict, NULL);
-
- msg (SE, _("`%s' is not a system or portable file."),
- fh_get_file_name (handle));
- return NULL;
+ return class->open (handle);
}
case FH_REF_INLINE:
return NULL;
case FH_REF_DATASET:
- return dataset_reader_open (handle, dict);
+ return dataset_reader_class.open (handle);
}
NOT_REACHED ();
}
+
+bool
+any_reader_close (struct any_reader *any_reader)
+{
+ return any_reader ? any_reader->klass->close (any_reader) : true;
+}
+
+struct casereader *
+any_reader_decode (struct any_reader *any_reader,
+ const char *encoding,
+ struct dictionary **dictp,
+ struct any_read_info *info)
+{
+ const struct any_reader_class *class = any_reader->klass;
+ struct casereader *reader;
+
+ reader = any_reader->klass->decode (any_reader, encoding, dictp, info);
+ if (reader && info)
+ info->klass = class;
+ return reader;
+}
+
+size_t
+any_reader_get_strings (const struct any_reader *any_reader, struct pool *pool,
+ char ***labels, bool **ids, char ***values)
+{
+ return (any_reader->klass->get_strings
+ ? any_reader->klass->get_strings (any_reader, pool, labels, ids,
+ values)
+ : 0);
+}
+
+struct casereader *
+any_reader_open_and_decode (struct file_handle *handle,
+ const char *encoding,
+ struct dictionary **dictp,
+ struct any_read_info *info)
+{
+ struct any_reader *any_reader = any_reader_open (handle);
+ return (any_reader
+ ? any_reader_decode (any_reader, encoding, dictp, info)
+ : NULL);
+}
+\f
+struct dataset_reader
+ {
+ struct any_reader any_reader;
+ struct dictionary *dict;
+ struct casereader *reader;
+ };
+
+/* Opens FH, which must have referent type FH_REF_DATASET, and returns a
+ dataset_reader for it, or a null pointer on failure. Stores a copy of the
+ dictionary for the dataset file into *DICT. The caller takes ownership of
+ the casereader and the dictionary. */
+static struct any_reader *
+dataset_reader_open (struct file_handle *fh)
+{
+ struct dataset_reader *reader;
+ struct dataset *ds;
+
+ /* We don't bother doing fh_lock or fh_ref on the file handle,
+ as there's no advantage in this case, and doing these would
+ require us to keep track of the "struct file_handle" and
+ "struct fh_lock" and undo our work later. */
+ assert (fh_get_referent (fh) == FH_REF_DATASET);
+
+ ds = fh_get_dataset (fh);
+ if (ds == NULL || !dataset_has_source (ds))
+ {
+ msg (SE, _("Cannot read from dataset %s because no dictionary or data "
+ "has been written to it yet."),
+ fh_get_name (fh));
+ return NULL;
+ }
+
+ reader = xmalloc (sizeof *reader);
+ reader->any_reader.klass = &dataset_reader_class;
+ reader->dict = dict_clone (dataset_dict (ds));
+ reader->reader = casereader_clone (dataset_source (ds));
+ return &reader->any_reader;
+}
+
+static struct dataset_reader *
+dataset_reader_cast (const struct any_reader *r_)
+{
+ assert (r_->klass == &dataset_reader_class);
+ return UP_CAST (r_, struct dataset_reader, any_reader);
+}
+
+static bool
+dataset_reader_close (struct any_reader *r_)
+{
+ struct dataset_reader *r = dataset_reader_cast (r_);
+ dict_destroy (r->dict);
+ casereader_destroy (r->reader);
+ free (r);
+
+ return true;
+}
+
+static struct casereader *
+dataset_reader_decode (struct any_reader *r_, const char *encoding UNUSED,
+ struct dictionary **dictp, struct any_read_info *info)
+{
+ struct dataset_reader *r = dataset_reader_cast (r_);
+ struct casereader *reader;
+
+ *dictp = r->dict;
+ reader = r->reader;
+ if (info)
+ {
+ memset (info, 0, sizeof *info);
+ info->integer_format = INTEGER_NATIVE;
+ info->float_format = FLOAT_NATIVE_DOUBLE;
+ info->compression = ANY_COMP_NONE;
+ info->case_cnt = casereader_get_case_cnt (reader);
+ }
+ free (r);
+
+ return reader;
+}
+
+static const struct any_reader_class dataset_reader_class =
+ {
+ N_("Dataset"),
+ NULL,
+ dataset_reader_open,
+ dataset_reader_close,
+ dataset_reader_decode,
+ NULL,
+ };
projects / pspp / blobdiff