1 /* PSPP - computes sample statistics.
2 Copyright (C) 1997-9, 2000 Free Software Foundation, Inc.
3 Written by Ben Pfaff <blp@gnu.org>.
5 This program is free software; you can redistribute it and/or
6 modify it under the terms of the GNU General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 This program is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
26 typedef struct write_case_data *write_case_data;
27 typedef int write_case_func (write_case_data);
29 /* The current active file, from which cases are read. */
30 extern struct case_source *vfm_source;
35 const struct case_source_class *class; /* Class. */
36 void *aux; /* Auxiliary data. */
39 /* A case source class. */
40 struct case_source_class
42 const char *name; /* Identifying name. */
44 /* Returns the exact number of cases that READ will pass to
45 WRITE_CASE, if known, or -1 otherwise. */
46 int (*count) (const struct case_source *);
48 /* Reads the cases one by one into C and for each one calls
49 WRITE_CASE passing the given AUX data. */
50 void (*read) (struct case_source *,
52 write_case_func *write_case, write_case_data aux);
54 /* Destroys the source. */
55 void (*destroy) (struct case_source *);
58 extern const struct case_source_class storage_source_class;
59 extern const struct case_source_class file_type_source_class;
60 extern const struct case_source_class input_program_source_class;
63 struct case_source *create_case_source (const struct case_source_class *,
65 void free_case_source (struct case_source *);
67 int case_source_is_complex (const struct case_source *);
68 int case_source_is_class (const struct case_source *,
69 const struct case_source_class *);
71 struct casefile *storage_source_get_casefile (struct case_source *);
72 struct case_source *storage_source_create (struct casefile *);
74 /* The replacement active file, to which cases are written. */
75 extern struct case_sink *vfm_sink;
80 const struct case_sink_class *class; /* Class. */
81 void *aux; /* Auxiliary data. */
82 size_t value_cnt; /* Number of `union value's in case. */
85 /* A case sink class. */
86 struct case_sink_class
88 const char *name; /* Identifying name. */
90 /* Opens the sink for writing. */
91 void (*open) (struct case_sink *);
93 /* Writes a case to the sink. */
94 void (*write) (struct case_sink *, const struct ccase *);
96 /* Closes and destroys the sink. */
97 void (*destroy) (struct case_sink *);
99 /* Closes the sink and returns a source that can read back
100 the cases that were written, perhaps transformed in some
101 way. The sink must still be separately destroyed by
102 calling destroy(). */
103 struct case_source *(*make_source) (struct case_sink *);
106 extern const struct case_sink_class storage_sink_class;
107 extern const struct case_sink_class null_sink_class;
109 struct case_sink *create_case_sink (const struct case_sink_class *,
110 const struct dictionary *,
112 void case_sink_open (struct case_sink *);
113 void case_sink_write (struct case_sink *, const struct ccase *);
114 void case_sink_destroy (struct case_sink *);
115 void free_case_sink (struct case_sink *);
117 /* Number of cases to lag. */
120 void procedure (int (*proc_func) (struct ccase *, void *aux), void *aux);
121 void procedure_with_splits (void (*begin_func) (void *aux),
122 int (*proc_func) (struct ccase *, void *aux),
123 void (*end_func) (void *aux),
125 struct ccase *lagged_case (int n_before);
127 void multipass_procedure_with_splits (void (*) (const struct casefile *,
131 time_t vfm_last_invocation (void);