src/cdata.c

   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  */
  27
  28 /*
  29  * A PostgreSQL data-type providing consolidated data points.
  30  */
  31
  32 #include "postrr.h"
  33
  34 #include <errno.h>
  35 #include <string.h>
  36
  37 #include <postgres.h>
  38 #include <fmgr.h>
  39
  40 /* Postgres utilities */
  41 #include <catalog/pg_type.h>
  42 #include <utils/array.h>
  43
  44 enum {
  45         CF_AVG = 0,
  46         CF_MIN = 1,
  47         CF_MAX = 2
  48 };
  49
  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")
  57
  58 /*
  59  * data type
  60  */
  61
  62 struct cdata {
  63         float8 value;
  64         int32 undef_num;
  65         int32 val_num;
  66         int32 cf;
  67 };
  68
  69 /*
  70  * prototypes for PostgreSQL functions
  71  */
  72
  73 PG_FUNCTION_INFO_V1(cdata_validate);
  74
  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);
  79
  80 PG_FUNCTION_INFO_V1(cdata_to_cdata);
  81 PG_FUNCTION_INFO_V1(int32_to_cdata);
  82
  83 /*
  84  * public API
  85  */
  86
  87 Datum
  88 cdata_validate(PG_FUNCTION_ARGS)
  89 {
  90         char   type_info[1024];
  91         char  *result;
  92         size_t req_len;
  93         size_t len;
  94
  95         if (PG_NARGS() != 1)
  96                 ereport(ERROR, (
  97                                         errmsg("cdata_validate() expect one argument"),
  98                                         errhint("Usage cdata_validate(expected_size)")
  99                                 ));
 100
 101         req_len = (size_t)PG_GETARG_UINT32(0);
 102         len = sizeof(cdata_t);
 103
 104         if (req_len != len)
 105                 ereport(ERROR, (
 106                                         errmsg("length of the cdata type "
 107                                                 "does not match the expected length"),
 108                                         errhint("Please report a bug against PostRR")
 109                                 ));
 110
 111         snprintf(type_info, sizeof(type_info),
 112                         "cdata validated successfully; type length = %zu", len);
 113         type_info[sizeof(type_info) - 1] = '\0';
 114
 115         result = pstrdup(type_info);
 116         PG_RETURN_CSTRING(result);
 117 } /* cdata_validate */
 118
 119 Datum
 120 cdata_in(PG_FUNCTION_ARGS)
 121 {
 122         cdata_t *data;
 123         int32 typmod;
 124
 125         char *val_str, *orig;
 126         char *endptr = NULL;
 127
 128         if (PG_NARGS() != 3)
 129                 ereport(ERROR, (
 130                                         errmsg("cdata_in() expects three arguments"),
 131                                         errhint("Usage: cdata_in(col_name, oid, typmod)")
 132                                 ));
 133
 134         data = (cdata_t *)palloc0(sizeof(*data));
 135
 136         val_str = PG_GETARG_CSTRING(0);
 137         typmod  = PG_GETARG_INT32(2);
 138
 139         orig = val_str;
 140         while ((*val_str != '\0') && isspace((int)*val_str))
 141                 ++val_str;
 142
 143         if (*val_str == '\0')
 144                 ereport(ERROR, (
 145                                         errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 146                                         errmsg("invalid input syntax for cdata: \"%s\"", orig)
 147                                 ));
 148
 149         errno = 0;
 150         data->value   = strtod(val_str, &endptr);
 151         data->val_num = 1;
 152
 153         if ((endptr == val_str) || errno)
 154                 ereport(ERROR, (
 155                                         errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 156                                         errmsg("invalid input syntax for cdata: \"%s\"", orig)
 157                                 ));
 158
 159         while ((*endptr != '\0') && isspace((int)*endptr))
 160                 ereport(ERROR, (
 161                                         errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 162                                         errmsg("invalid input syntax for cdata: \"%s\"", orig)
 163                                 ));
 164
 165         if (typmod > 0)
 166                 data->cf = typmod;
 167         else
 168                 data->cf = 0;
 169
 170         PG_RETURN_CDATA_P(data);
 171 } /* cdata_in */
 172
 173 Datum
 174 cdata_out(PG_FUNCTION_ARGS)
 175 {
 176         cdata_t *data;
 177
 178         char  cd_str[1024];
 179         char *result;
 180
 181         if (PG_NARGS() != 1)
 182                 ereport(ERROR, (
 183                                         errmsg("cdata_out() expects one argument"),
 184                                         errhint("Usage: cdata_out(cdata)")
 185                                 ));
 186
 187         data = PG_GETARG_CDATA_P(0);
 188
 189         snprintf(cd_str, sizeof(cd_str), "%g (U:%i/%i)",
 190                         data->value, data->undef_num, data->val_num);
 191
 192         result = pstrdup(cd_str);
 193         PG_RETURN_CSTRING(result);
 194 } /* cdata_out */
 195
 196 Datum
 197 cdata_typmodin(PG_FUNCTION_ARGS)
 198 {
 199         ArrayType *tm_array;
 200
 201         Datum *elem_values;
 202         int    n;
 203         char  *cf_str;
 204         int32  typmod = CF_AVG;
 205
 206         if (PG_NARGS() != 1)
 207                 ereport(ERROR, (
 208                                         errmsg("cdata_typmodin() expects one argument"),
 209                                         errhint("Usage: cdata_typmodin(array)")
 210                                 ));
 211
 212         tm_array = PG_GETARG_ARRAYTYPE_P(0);
 213
 214         if (ARR_ELEMTYPE(tm_array) != CSTRINGOID)
 215                 ereport(ERROR, (
 216                                         errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
 217                                         errmsg("typmod array must be type cstring[]")
 218                                 ));
 219
 220         if (ARR_NDIM(tm_array) != 1)
 221                 ereport(ERROR, (
 222                                         errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
 223                                         errmsg("typmod array must be one-dimensional")
 224                                 ));
 225
 226         deconstruct_array(tm_array, CSTRINGOID,
 227                         /* elmlen = */ -2, /* elmbyval = */ false, /* elmalign = */ 'c',
 228                         &elem_values, /* nullsp = */ NULL, &n);
 229
 230         if (n != 1)
 231                 ereport(ERROR, (
 232                                         errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 233                                         errmsg("cdata typmod array must have one element")
 234                                 ));
 235
 236         cf_str = DatumGetCString(elem_values[0]);
 237         if (! strcasecmp(cf_str, "AVG"))
 238                 typmod = CF_AVG;
 239         else if (! strcasecmp(cf_str, "MIN"))
 240                 typmod = CF_MIN;
 241         else if (! strcasecmp(cf_str, "MAX"))
 242                 typmod = CF_MAX;
 243         else
 244                 ereport(ERROR, (
 245                                         errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 246                                         errmsg("invalid cdata typmod: %s", cf_str)
 247                                 ));
 248
 249         PG_RETURN_INT32(typmod);
 250 } /* cdata_typmodin */
 251
 252 Datum
 253 cdata_typmodout(PG_FUNCTION_ARGS)
 254 {
 255         int32 typmod;
 256         char  tm_str[32];
 257         char *result;
 258
 259         if (PG_NARGS() != 1)
 260                 ereport(ERROR, (
 261                                         errmsg("cdata_typmodout() expects one argument"),
 262                                         errhint("Usage: cdata_typmodout(typmod)")
 263                                 ));
 264
 265         typmod = PG_GETARG_INT32(0);
 266         snprintf(tm_str, sizeof(tm_str), "('%s')", CF_TO_STR(typmod));
 267         tm_str[sizeof(tm_str) - 1] = '\0';
 268         result = pstrdup(tm_str);
 269         PG_RETURN_CSTRING(result);
 270 } /* cdata_typmodout */
 271
 272 Datum
 273 cdata_to_cdata(PG_FUNCTION_ARGS)
 274 {
 275         cdata_t *data;
 276         int32 typmod;
 277
 278         if (PG_NARGS() != 3)
 279                 ereport(ERROR, (
 280                                         errmsg("cdata_to_cdata() "
 281                                                 "expects three arguments"),
 282                                         errhint("Usage: cdata_to_cdata"
 283                                                 "(cdata, typmod, is_explicit)")
 284                                 ));
 285
 286         data   = PG_GETARG_CDATA_P(0);
 287         typmod = PG_GETARG_INT32(1);
 288
 289         if ((data->cf >= 0) && (data->cf != typmod) && (data->val_num > 1))
 290                 ereport(ERROR, (
 291                                         errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 292                                         errmsg("invalid cast: cannot cast cdata "
 293                                                 "with different typmod (yet)")
 294                                 ));
 295
 296         data->cf = typmod;
 297         PG_RETURN_CDATA_P(data);
 298 } /* cdata_to_cdata */
 299
 300 Datum
 301 int32_to_cdata(PG_FUNCTION_ARGS)
 302 {
 303         int32 i_val;
 304         int32 typmod;
 305
 306         cdata_t *data;
 307
 308         if (PG_NARGS() != 3)
 309                 ereport(ERROR, (
 310                                         errmsg("int32_to_cdata() expects three arguments"),
 311                                         errhint("Usage: int32_to_cdata"
 312                                                 "(integer, typmod, is_explicit)")
 313                                 ));
 314
 315         i_val  = PG_GETARG_INT32(0);
 316         typmod = PG_GETARG_INT32(1);
 317
 318         data = (cdata_t *)palloc0(sizeof(*data));
 319
 320         data->value     = (float8)i_val;
 321         data->undef_num = 0;
 322         data->val_num   = 1;
 323
 324         if (typmod >= 0)
 325                 data->cf = typmod;
 326         else
 327                 data->cf = CF_AVG;
 328
 329         PG_RETURN_CDATA_P(data);
 330 } /* int32_to_cdata */
 331
 332 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 333