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."));
79 if (do_if->n_clauses >= *allocated_clauses)
80 do_if->clauses = x2nrealloc (do_if->clauses, allocated_clauses,
81 sizeof *do_if->clauses);
82 struct clause *clause = &do_if->clauses[do_if->n_clauses++];
84 *clause = (struct clause) { .location = NULL };
87 clause->condition = expr_parse_bool (lexer, ds);
88 if (!clause->condition)
89 lex_discard_rest_of_command (lexer);
91 clause->location = lex_ofs_location (lexer, 0, lex_ofs (lexer));
93 lex_end_of_command (lexer);
96 proc_push_transformations (ds);
100 finish_clause (struct dataset *ds, struct do_if_trns *do_if)
102 struct clause *clause = &do_if->clauses[do_if->n_clauses - 1];
103 proc_pop_transformations (ds, &clause->xforms);
108 cmd_do_if (struct lexer *lexer, struct dataset *ds)
110 struct do_if_trns *do_if = xmalloc (sizeof *do_if);
111 *do_if = (struct do_if_trns) { .n_clauses = 0 };
113 size_t allocated_clauses = 0;
116 start_clause (lexer, ds, true, do_if, &allocated_clauses, &ok);
117 while (!lex_match_phrase (lexer, "END IF"))
119 if (lex_token (lexer) == T_STOP)
121 lex_error (lexer, NULL);
124 else if (lex_match_phrase (lexer, "ELSE IF"))
126 finish_clause (ds, do_if);
127 start_clause (lexer, ds, true, do_if, &allocated_clauses, &ok);
129 else if (lex_match_id (lexer, "ELSE"))
131 finish_clause (ds, do_if);
132 start_clause (lexer, ds, false, do_if, &allocated_clauses, &ok);
135 cmd_parse_in_state (lexer, ds,
137 ? CMD_STATE_NESTED_INPUT_PROGRAM
138 : CMD_STATE_NESTED_DATA));
140 finish_clause (ds, do_if);
142 add_transformation (ds, &do_if_trns_class, do_if);
144 return ok ? CMD_SUCCESS : CMD_FAILURE;
148 cmd_inside_do_if (struct lexer *lexer UNUSED, struct dataset *ds UNUSED)
150 msg (SE, _("This command cannot appear outside DO IF...END IF."));
154 static const struct trns_chain *
155 do_if_find_clause (const struct do_if_trns *do_if,
156 struct ccase *c, casenumber case_num)
158 for (size_t i = 0; i < do_if->n_clauses; i++)
160 const struct clause *clause = &do_if->clauses[i];
161 if (!clause->condition)
162 return &clause->xforms;
164 double boolean = expr_evaluate_num (clause->condition, c, case_num);
166 return boolean == SYSMIS ? NULL : &clause->xforms;
171 static enum trns_result
172 do_if_trns_proc (void *do_if_, struct ccase **c, casenumber case_num)
174 struct do_if_trns *do_if = do_if_;
176 const struct trns_chain *chain;
180 chain = do_if->resume;
182 do_if->resume = NULL;
187 chain = do_if_find_clause (do_if, *c, case_num);
189 return TRNS_CONTINUE;
193 for (size_t i = start; i < chain->n; i++)
195 const struct transformation *trns = &chain->xforms[i];
196 enum trns_result r = trns->class->execute (trns->aux, c, case_num);
209 do_if->resume = chain;
214 return TRNS_CONTINUE;
218 do_if_trns_free (void *do_if_)
220 struct do_if_trns *do_if = do_if_;
222 for (size_t i = 0; i < do_if->n_clauses; i++)
224 struct clause *clause = &do_if->clauses[i];
226 msg_location_destroy (clause->location);
227 expr_free (clause->condition);
229 trns_chain_uninit (&clause->xforms);
231 free (do_if->clauses);
236 static const struct trns_class do_if_trns_class = {
238 .execute = do_if_trns_proc,
239 .destroy = do_if_trns_free,