-/* PSPP - computes sample statistics.
- Copyright (C) 2006 Free Software Foundation, Inc.
+/* PSPP - a program for statistical analysis.
+ Copyright (C) 2006, 2010 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include "any-reader.h"
#include "gettext.h"
#define _(msgid) gettext (msgid)
-/* Type of file backing an any_reader. */
-enum any_reader_type
- {
- SYSTEM_FILE, /* System file. */
- PORTABLE_FILE, /* Portable file. */
- SCRATCH_FILE /* Scratch file. */
- };
-
-/* Reader for any type of case-structured file. */
-struct any_reader
- {
- enum any_reader_type type; /* Type of file. */
- void *private; /* Private data. */
- };
-
/* Result of type detection. */
-enum detect_result
+enum detect_result
{
YES, /* It is this type. */
NO, /* It is not this type. */
IO_ERROR /* File couldn't be opened. */
};
-/* Tries to detect whether HANDLE represents a given type of
- file, by opening the file and passing it to DETECT, and
- returns a detect_result. */
+/* 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 (struct file_handle *handle, bool (*detect) (FILE *))
+try_detect (const char *file_name, bool (*detect) (FILE *))
{
FILE *file;
bool is_type;
- file = fn_open (fh_get_file_name (handle), "rb");
+ file = fn_open (file_name, "rb");
if (file == NULL)
{
- msg (ME, _("An error occurred while opening \"%s\": %s."),
- fh_get_file_name (handle), strerror (errno));
+ msg (ME, _("An error occurred while opening `%s': %s."),
+ file_name, strerror (errno));
return IO_ERROR;
}
-
+
is_type = detect (file);
-
- fn_close (fh_get_file_name (handle), file);
+
+ fn_close (file_name, file);
return is_type ? YES : NO;
}
-/* If PRIVATE is non-null, creates and returns a new any_reader,
- initializing its fields to TYPE and PRIVATE. If PRIVATE is a
- null pointer, just returns a null pointer. */
-static struct any_reader *
-make_any_reader (enum any_reader_type type, void *private)
+/* Returns true if any_reader_open() would be able to open FILE as a data
+ file, false otherwise. */
+bool
+any_reader_may_open (const char *file)
{
- if (private != NULL)
- {
- struct any_reader *reader = xmalloc (sizeof *reader);
- reader->type = type;
- reader->private = private;
- return reader;
- }
- else
- return NULL;
+ return (try_detect (file, sfm_detect) == YES
+ || try_detect (file, pfm_detect) == YES);
}
-/* Creates an any_reader for HANDLE. On success, returns the new
- any_reader and stores the file's dictionary into *DICT. On
+/* 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. */
-struct any_reader *
+struct casereader *
any_reader_open (struct file_handle *handle, struct dictionary **dict)
{
- switch (fh_get_referent (handle))
+ switch (fh_get_referent (handle))
{
case FH_REF_FILE:
{
enum detect_result result;
- result = try_detect (handle, sfm_detect);
+ result = try_detect (fh_get_file_name (handle), sfm_detect);
if (result == IO_ERROR)
return NULL;
else if (result == YES)
- return make_any_reader (SYSTEM_FILE,
- sfm_open_reader (handle, dict, NULL));
+ return sfm_open_reader (handle, dict, NULL);
- result = try_detect (handle, pfm_detect);
+ result = try_detect (fh_get_file_name (handle), pfm_detect);
if (result == IO_ERROR)
return NULL;
else if (result == YES)
- return make_any_reader (PORTABLE_FILE,
- pfm_open_reader (handle, dict, NULL));
+ return pfm_open_reader (handle, dict, NULL);
- msg (SE, _("\"%s\" is not a system or portable file."),
+ msg (SE, _("`%s' is not a system or portable file."),
fh_get_file_name (handle));
return NULL;
}
return NULL;
case FH_REF_SCRATCH:
- return make_any_reader (SCRATCH_FILE,
- scratch_reader_open (handle, dict));
- }
- NOT_REACHED ();
-}
-
-/* Reads a single case from READER into C.
- Returns true if successful, false at end of file or on error. */
-bool
-any_reader_read (struct any_reader *reader, struct ccase *c)
-{
- switch (reader->type)
- {
- case SYSTEM_FILE:
- return sfm_read_case (reader->private, c);
-
- case PORTABLE_FILE:
- return pfm_read_case (reader->private, c);
-
- case SCRATCH_FILE:
- return scratch_reader_read_case (reader->private, c);
+ return scratch_reader_open (handle, dict);
}
NOT_REACHED ();
}
-
-/* Returns true if an I/O error has occurred on READER, false
- otherwise. */
-bool
-any_reader_error (struct any_reader *reader)
-{
- switch (reader->type)
- {
- case SYSTEM_FILE:
- return sfm_read_error (reader->private);
-
- case PORTABLE_FILE:
- return pfm_read_error (reader->private);
-
- case SCRATCH_FILE:
- return scratch_reader_error (reader->private);
- }
- NOT_REACHED ();
-}
-
-/* Closes READER. */
-void
-any_reader_close (struct any_reader *reader)
-{
- if (reader == NULL)
- return;
-
- switch (reader->type)
- {
- case SYSTEM_FILE:
- sfm_close_reader (reader->private);
- break;
-
- case PORTABLE_FILE:
- pfm_close_reader (reader->private);
- break;
-
- case SCRATCH_FILE:
- scratch_reader_close (reader->private);
- break;
-
- default:
- NOT_REACHED ();
- }
-
- free (reader);
-}