1 /* PSPP - a program for statistical analysis.
2 Copyright (C) 1997-9, 2000, 2009-2012 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "data/dataset.h"
22 #include "data/transformations.h"
23 #include "language/command.h"
24 #include "language/data-io/inpt-pgm.h"
25 #include "language/expressions/public.h"
26 #include "language/lexer/lexer.h"
27 #include "libpspp/compiler.h"
28 #include "libpspp/message.h"
29 #include "libpspp/str.h"
31 #include "gl/xalloc.h"
34 #define _(msgid) gettext (msgid)
36 /* A conditional clause. */
39 struct msg_location *location;
40 struct expression *condition; /* Test expression; NULL for ELSE clause. */
41 struct trns_chain xforms;
44 /* DO IF transformation. */
47 struct clause *clauses; /* Clauses. */
48 size_t n_clauses; /* Number of clauses. */
50 const struct trns_chain *resume;
54 static const struct trns_class do_if_trns_class;
57 start_clause (struct lexer *lexer, struct dataset *ds,
58 bool condition, struct do_if_trns *do_if,
59 size_t *allocated_clauses, bool *ok)
61 if (*ok && do_if->n_clauses > 0
62 && !do_if->clauses[do_if->n_clauses - 1].condition)
65 msg (SE, _("ELSE IF is not allowed following ELSE "
66 "within DO IF...END IF."));
68 msg (SE, _("Only one ELSE is allowed within DO IF...END IF."));
70 msg_at (SN, do_if->clauses[do_if->n_clauses - 1].location,
71 _("This is the location of the previous ELSE clause."));
73 msg_at (SN, do_if->clauses[0].location,
74 _("This is the location of the DO IF command."));
77 if (do_if->n_clauses >= *allocated_clauses)
78 do_if->clauses = x2nrealloc (do_if->clauses, allocated_clauses,
79 sizeof *do_if->clauses);
80 struct clause *clause = &do_if->clauses[do_if->n_clauses++];
82 *clause = (struct clause) { .location = NULL };
85 clause->condition = expr_parse_bool (lexer, ds);
86 if (!clause->condition)
87 lex_discard_rest_of_command (lexer);
89 clause->location = lex_ofs_location (lexer, 0, lex_ofs (lexer));
91 lex_end_of_command (lexer);
94 proc_push_transformations (ds);
98 finish_clause (struct dataset *ds, struct do_if_trns *do_if)
100 struct clause *clause = &do_if->clauses[do_if->n_clauses - 1];
101 proc_pop_transformations (ds, &clause->xforms);
106 cmd_do_if (struct lexer *lexer, struct dataset *ds)
108 struct do_if_trns *do_if = xmalloc (sizeof *do_if);
109 *do_if = (struct do_if_trns) { .n_clauses = 0 };
111 size_t allocated_clauses = 0;
114 start_clause (lexer, ds, true, do_if, &allocated_clauses, &ok);
115 while (!lex_match_phrase (lexer, "END IF"))
117 if (lex_token (lexer) == T_STOP)
119 lex_error (lexer, NULL);
123 else if (lex_match_phrase (lexer, "ELSE IF"))
125 finish_clause (ds, do_if);
126 start_clause (lexer, ds, true, do_if, &allocated_clauses, &ok);
128 else if (lex_match_id (lexer, "ELSE"))
130 finish_clause (ds, do_if);
131 start_clause (lexer, ds, false, do_if, &allocated_clauses, &ok);
134 cmd_parse_in_state (lexer, ds,
136 ? CMD_STATE_NESTED_INPUT_PROGRAM
137 : CMD_STATE_NESTED_DATA));
139 finish_clause (ds, do_if);
141 add_transformation (ds, &do_if_trns_class, do_if);
143 return ok ? CMD_SUCCESS : CMD_CASCADING_FAILURE;
146 static const struct trns_chain *
147 do_if_find_clause (const struct do_if_trns *do_if,
148 struct ccase *c, casenumber case_num)
150 for (size_t i = 0; i < do_if->n_clauses; i++)
152 const struct clause *clause = &do_if->clauses[i];
153 if (!clause->condition)
154 return &clause->xforms;
156 double boolean = expr_evaluate_num (clause->condition, c, case_num);
158 return boolean == SYSMIS ? NULL : &clause->xforms;
163 static enum trns_result
164 do_if_trns_proc (void *do_if_, struct ccase **c, casenumber case_num)
166 struct do_if_trns *do_if = do_if_;
168 const struct trns_chain *chain;
172 chain = do_if->resume;
174 do_if->resume = NULL;
179 chain = do_if_find_clause (do_if, *c, case_num);
181 return TRNS_CONTINUE;
185 for (size_t i = start; i < chain->n; i++)
187 const struct transformation *trns = &chain->xforms[i];
188 enum trns_result r = trns->class->execute (trns->aux, c, case_num);
201 do_if->resume = chain;
206 return TRNS_CONTINUE;
210 do_if_trns_free (void *do_if_)
212 struct do_if_trns *do_if = do_if_;
214 for (size_t i = 0; i < do_if->n_clauses; i++)
216 struct clause *clause = &do_if->clauses[i];
218 msg_location_destroy (clause->location);
219 expr_free (clause->condition);
221 trns_chain_uninit (&clause->xforms);
223 free (do_if->clauses);
228 static const struct trns_class do_if_trns_class = {
230 .execute = do_if_trns_proc,
231 .destroy = do_if_trns_free,