7ee14e643b9d8081997073e4188b2fca79c58c00
1 /*
2 * PostRR - src/cdata.c
3 * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
28 /*
29 * A PostgreSQL data-type providing consolidated data points.
30 */
32 #include "postrr.h"
34 #include <errno.h>
35 #include <string.h>
37 #include <postgres.h>
38 #include <fmgr.h>
40 /* Postgres utilities */
41 #include <catalog/pg_type.h>
42 #include <utils/array.h>
44 enum {
45 CF_AVG = 0,
46 CF_MIN = 1,
47 CF_MAX = 2
48 };
50 #define CF_TO_STR(cf) \
51 (((cf) == CF_AVG) \
52 ? "AVG" \
53 : ((cf) == CF_MIN) \
54 ? "MIN" \
55 : ((cf) == CF_MAX) \
56 ? "MAX" : "UNKNOWN")
58 /*
59 * data type
60 */
62 struct cdata {
63 float8 value;
64 int32 undef_num;
65 int32 val_num;
66 int32 cf;
67 };
69 /*
70 * prototypes for PostgreSQL functions
71 */
73 PG_FUNCTION_INFO_V1(cdata_validate);
75 PG_FUNCTION_INFO_V1(cdata_in);
76 PG_FUNCTION_INFO_V1(cdata_out);
77 PG_FUNCTION_INFO_V1(cdata_typmodin);
78 PG_FUNCTION_INFO_V1(cdata_typmodout);
80 PG_FUNCTION_INFO_V1(cdata_to_cdata);
81 PG_FUNCTION_INFO_V1(int32_to_cdata);
82 PG_FUNCTION_INFO_V1(cdata_to_float8);
84 PG_FUNCTION_INFO_V1(cdata_update);
86 /*
87 * public API
88 */
90 Datum
91 cdata_validate(PG_FUNCTION_ARGS)
92 {
93 char type_info[1024];
94 char *result;
95 size_t req_len;
96 size_t len;
98 if (PG_NARGS() != 1)
99 ereport(ERROR, (
100 errmsg("cdata_validate() expect one argument"),
101 errhint("Usage cdata_validate(expected_size)")
102 ));
104 req_len = (size_t)PG_GETARG_UINT32(0);
105 len = sizeof(cdata_t);
107 if (req_len != len)
108 ereport(ERROR, (
109 errmsg("length of the cdata type "
110 "does not match the expected length"),
111 errhint("Please report a bug against PostRR")
112 ));
114 snprintf(type_info, sizeof(type_info),
115 "cdata validated successfully; type length = %zu", len);
116 type_info[sizeof(type_info) - 1] = '\0';
118 result = pstrdup(type_info);
119 PG_RETURN_CSTRING(result);
120 } /* cdata_validate */
122 Datum
123 cdata_in(PG_FUNCTION_ARGS)
124 {
125 cdata_t *data;
126 int32 typmod;
128 char *val_str, *orig;
129 char *endptr = NULL;
131 if (PG_NARGS() != 3)
132 ereport(ERROR, (
133 errmsg("cdata_in() expects three arguments"),
134 errhint("Usage: cdata_in(col_name, oid, typmod)")
135 ));
137 data = (cdata_t *)palloc0(sizeof(*data));
139 val_str = PG_GETARG_CSTRING(0);
140 typmod = PG_GETARG_INT32(2);
142 orig = val_str;
143 while ((*val_str != '\0') && isspace((int)*val_str))
144 ++val_str;
146 if (*val_str == '\0')
147 ereport(ERROR, (
148 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
149 errmsg("invalid input syntax for cdata: \"%s\"", orig)
150 ));
152 errno = 0;
153 data->value = strtod(val_str, &endptr);
154 data->val_num = 1;
156 if ((endptr == val_str) || errno)
157 ereport(ERROR, (
158 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
159 errmsg("invalid input syntax for cdata: \"%s\"", orig)
160 ));
162 while ((*endptr != '\0') && isspace((int)*endptr))
163 ereport(ERROR, (
164 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
165 errmsg("invalid input syntax for cdata: \"%s\"", orig)
166 ));
168 if (typmod > 0)
169 data->cf = typmod;
170 else
171 data->cf = 0;
173 PG_RETURN_CDATA_P(data);
174 } /* cdata_in */
176 Datum
177 cdata_out(PG_FUNCTION_ARGS)
178 {
179 cdata_t *data;
181 char cd_str[1024];
182 char *result;
184 if (PG_NARGS() != 1)
185 ereport(ERROR, (
186 errmsg("cdata_out() expects one argument"),
187 errhint("Usage: cdata_out(cdata)")
188 ));
190 data = PG_GETARG_CDATA_P(0);
192 snprintf(cd_str, sizeof(cd_str), "%g (%s U:%i/%i)",
193 data->value, CF_TO_STR(data->cf),
194 data->undef_num, data->val_num);
196 result = pstrdup(cd_str);
197 PG_RETURN_CSTRING(result);
198 } /* cdata_out */
200 Datum
201 cdata_typmodin(PG_FUNCTION_ARGS)
202 {
203 ArrayType *tm_array;
205 Datum *elem_values;
206 int n;
207 char *cf_str;
208 int32 typmod = CF_AVG;
210 if (PG_NARGS() != 1)
211 ereport(ERROR, (
212 errmsg("cdata_typmodin() expects one argument"),
213 errhint("Usage: cdata_typmodin(array)")
214 ));
216 tm_array = PG_GETARG_ARRAYTYPE_P(0);
218 if (ARR_ELEMTYPE(tm_array) != CSTRINGOID)
219 ereport(ERROR, (
220 errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
221 errmsg("typmod array must be type cstring[]")
222 ));
224 if (ARR_NDIM(tm_array) != 1)
225 ereport(ERROR, (
226 errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
227 errmsg("typmod array must be one-dimensional")
228 ));
230 deconstruct_array(tm_array, CSTRINGOID,
231 /* elmlen = */ -2, /* elmbyval = */ false, /* elmalign = */ 'c',
232 &elem_values, /* nullsp = */ NULL, &n);
234 if (n != 1)
235 ereport(ERROR, (
236 errcode(ERRCODE_INVALID_PARAMETER_VALUE),
237 errmsg("cdata typmod array must have one element")
238 ));
240 cf_str = DatumGetCString(elem_values[0]);
241 if (! strcasecmp(cf_str, "AVG"))
242 typmod = CF_AVG;
243 else if (! strcasecmp(cf_str, "MIN"))
244 typmod = CF_MIN;
245 else if (! strcasecmp(cf_str, "MAX"))
246 typmod = CF_MAX;
247 else
248 ereport(ERROR, (
249 errcode(ERRCODE_INVALID_PARAMETER_VALUE),
250 errmsg("invalid cdata typmod: %s", cf_str)
251 ));
253 PG_RETURN_INT32(typmod);
254 } /* cdata_typmodin */
256 Datum
257 cdata_typmodout(PG_FUNCTION_ARGS)
258 {
259 int32 typmod;
260 char tm_str[32];
261 char *result;
263 if (PG_NARGS() != 1)
264 ereport(ERROR, (
265 errmsg("cdata_typmodout() expects one argument"),
266 errhint("Usage: cdata_typmodout(typmod)")
267 ));
269 typmod = PG_GETARG_INT32(0);
270 snprintf(tm_str, sizeof(tm_str), "('%s')", CF_TO_STR(typmod));
271 tm_str[sizeof(tm_str) - 1] = '\0';
272 result = pstrdup(tm_str);
273 PG_RETURN_CSTRING(result);
274 } /* cdata_typmodout */
276 Datum
277 cdata_to_cdata(PG_FUNCTION_ARGS)
278 {
279 cdata_t *data;
280 int32 typmod;
282 if (PG_NARGS() != 3)
283 ereport(ERROR, (
284 errmsg("cdata_to_cdata() "
285 "expects three arguments"),
286 errhint("Usage: cdata_to_cdata"
287 "(cdata, typmod, is_explicit)")
288 ));
290 data = PG_GETARG_CDATA_P(0);
291 typmod = PG_GETARG_INT32(1);
293 if ((data->cf >= 0) && (data->cf != typmod) && (data->val_num > 1))
294 ereport(ERROR, (
295 errcode(ERRCODE_INVALID_PARAMETER_VALUE),
296 errmsg("invalid cast: cannot cast cdata "
297 "with different typmod (yet)")
298 ));
300 data->cf = typmod;
301 PG_RETURN_CDATA_P(data);
302 } /* cdata_to_cdata */
304 Datum
305 int32_to_cdata(PG_FUNCTION_ARGS)
306 {
307 int32 i_val;
308 int32 typmod;
310 cdata_t *data;
312 if (PG_NARGS() != 3)
313 ereport(ERROR, (
314 errmsg("int32_to_cdata() expects three arguments"),
315 errhint("Usage: int32_to_cdata"
316 "(integer, typmod, is_explicit)")
317 ));
319 i_val = PG_GETARG_INT32(0);
320 typmod = PG_GETARG_INT32(1);
322 data = (cdata_t *)palloc0(sizeof(*data));
324 data->value = (float8)i_val;
325 data->undef_num = 0;
326 data->val_num = 1;
328 if (typmod >= 0)
329 data->cf = typmod;
330 else
331 data->cf = CF_AVG;
333 PG_RETURN_CDATA_P(data);
334 } /* int32_to_cdata */
336 Datum
337 cdata_to_float8(PG_FUNCTION_ARGS)
338 {
339 cdata_t *data;
341 if (PG_NARGS() != 1)
342 ereport(ERROR, (
343 errmsg("cdata_to_float8() expects one argument"),
344 errhint("Usage: cdata_to_float8(cdata)")
345 ));
347 data = PG_GETARG_CDATA_P(0);
348 PG_RETURN_FLOAT8(data->value);
349 } /* cdata_to_float8 */
351 Datum
352 cdata_update(PG_FUNCTION_ARGS)
353 {
354 cdata_t *data;
355 cdata_t *update;
357 if (PG_NARGS() != 2)
358 ereport(ERROR, (
359 errmsg("cdata_update() expects two arguments"),
360 errhint("Usage: cdata_update(cdata, cdata)")
361 ));
363 data = PG_GETARG_CDATA_P(0);
364 update = PG_GETARG_CDATA_P(1);
366 if (! data)
367 PG_RETURN_CDATA_P(update);
369 if (! update)
370 PG_RETURN_CDATA_P(data);
372 if ((data->cf != update->cf) && (update->val_num > 1))
373 ereport(ERROR, (
374 errcode(ERRCODE_INVALID_PARAMETER_VALUE),
375 errmsg("invalid update value: incompatible "
376 "consolidation function")
377 ));
379 switch (data->cf) {
380 case CF_AVG:
381 data->value = (data->value * (data->val_num - data->undef_num))
382 + (update->value * (update->val_num - update->undef_num));
383 data->value /= (data->val_num - data->undef_num)
384 + (update->val_num - update->undef_num);
385 break;
386 case CF_MIN:
387 data->value = (data->value <= update->value)
388 ? data->value : update->value;
389 break;
390 case CF_MAX:
391 data->value = (data->value >= update->value)
392 ? data->value : update->value;
393 break;
394 default:
395 ereport(ERROR, (
396 errcode(ERRCODE_DATA_CORRUPTED),
397 errmsg("unknown consolidation function %d",
398 data->cf)
399 ));
400 break;
401 }
403 data->undef_num += update->undef_num;
404 data->val_num += update->val_num;
405 PG_RETURN_CDATA_P(data);
406 } /* cdata_update */
408 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */