src/frontend/scanner.l

   1 /*
   2  * SysDB - src/frontend/scanner.l
   3  * Copyright (C) 2013 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
  30 #if HAVE_CONFIG_H
  31 #       include "config.h"
  32 #endif /* HAVE_CONFIG_H */
  33
  34 #include "core/data.h"
  35 #include "frontend/connection.h"
  36 #include "frontend/parser.h"
  37 #include "frontend/grammar.h"
  38 #include "utils/error.h"
  39
  40 #include <assert.h>
  41 #include <errno.h>
  42
  43 #include <string.h>
  44 #include <stdlib.h>
  45
  46 #include <time.h>
  47
  48 #define YY_EXTRA_TYPE sdb_fe_yyextra_t *
  49
  50 static struct {
  51         const char *name;
  52         int id;
  53 } reserved_words[] = {
  54         { "AND",        AND },
  55         { "END",        END },
  56         { "FETCH",      FETCH },
  57         { "FILTER",     FILTER },
  58         { "IS",         IS },
  59         { "LIST",       LIST },
  60         { "LOOKUP",     LOOKUP },
  61         { "MATCHING",   MATCHING },
  62         { "NOT",        NOT },
  63         { "NULL",       NULL_T },
  64         { "OR",         OR },
  65         { "START",      START },
  66         { "TIMESERIES", TIMESERIES },
  67 };
  68
  69 void
  70 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
  71
  72 %}
  73
  74 %option never-interactive
  75 %option reentrant
  76 %option bison-bridge
  77 %option bison-locations
  78 %option 8bit
  79 %option yylineno
  80 %option nodefault
  81 %option noinput
  82 %option nounput
  83 %option noyywrap
  84 %option verbose
  85 %option warn
  86 %option prefix="sdb_fe_yy" outfile="lex.yy.c"
  87
  88 %x CSC
  89
  90 whitespace              ([ \t\n\r\f]+)
  91 simple_comment  ("--"[^\n\r]*)
  92
  93 /*
  94  * C style comments
  95  */
  96 csc_start       \/\*
  97 csc_inside      ([^*/]+|[^*]\/|\*[^/])
  98 csc_end         \*\/
  99
 100 /*
 101  * Strings and identifiers.
 102  */
 103 identifier      ([A-Za-z_][A-Za-z_0-9$]*)
 104 /* TODO: fully support SQL strings */
 105 string          ('([^']|'')*')
 106
 107 /*
 108  * Numeric constants.
 109  */
 110 dec                     ([\+\-]?[0-9]+)
 111 exp                     ([\+\-]?[0-9]+[Ee]\+?[0-9]+)
 112 integer         ({dec}|{exp})
 113 float1          ([\+\-]?[0-9]+\.[0-9]*([Ee][\+\-]?[0-9]+)?)
 114 float2          ([\+\-]?[0-9]*\.[0-9]+([Ee][\+\-]?[0-9]+)?)
 115 float3          ([\+\-]?[0-9]+[Ee]\-[0-9]+)
 116 float4          ([\+\-]?[Ii][Nn][Ff]([Ii][Nn][Ii][Tt][Yy])?)
 117 float5          ([Nn][Aa][Nn])
 118 float           ({float1}|{float2}|{float3}|{float4}|{float5})
 119
 120 /*
 121  * Time constants.
 122  */
 123 date            ([0-9]{4}-[0-9]{2}-[0-9]{2})
 124 time            ([0-9]{1,2}:[0-9]{1,2}(:[0-9]{1,2}(\.[0-9]{1,9})?)?)
 125
 126 %%
 127
 128 {whitespace} |
 129 {simple_comment}        { /* ignore */ }
 130
 131 {csc_start}                     { BEGIN(CSC); }
 132 <CSC>{csc_inside}       { /* ignore */ }
 133 <CSC>{csc_end}          { BEGIN(INITIAL); }
 134 <CSC><<EOF>> {
 135                 sdb_fe_yyerror(yylloc, yyscanner, "unterminated C-style comment");
 136                 return SCANNER_ERROR;
 137         }
 138
 139 {identifier} {
 140                 size_t i;
 141                 for (i = 0; i < SDB_STATIC_ARRAY_LEN(reserved_words); ++i)
 142                         if (! strcasecmp(reserved_words[i].name, yytext))
 143                                 return reserved_words[i].id;
 144
 145                 yylval->str = strdup(yytext);
 146                 return IDENTIFIER;
 147         }
 148 {string} {
 149                 char *quot;
 150                 size_t len;
 151
 152                 /* remove the leading and trailing quote */
 153                 yytext[yyleng - 1] = '\0';
 154                 yylval->str = strdup(yytext + 1);
 155
 156                 quot = yylval->str;
 157                 len = yyleng - 2;
 158                 while ((quot = strstr(quot, "''")) != NULL) {
 159                         memmove(quot, quot + 1, len - (quot - yylval->str) - 1);
 160                         yylval->str[len - 1] = '\0';
 161                         --len;
 162                         ++quot;
 163                 }
 164                 return STRING;
 165         }
 166 {integer} {
 167                 yylval->data.data.integer = (int64_t)strtoll(yytext, NULL, 10);
 168                 yylval->data.type = SDB_TYPE_INTEGER;
 169                 return INTEGER;
 170         }
 171 {float} {
 172                 yylval->data.data.decimal = strtod(yytext, NULL);
 173                 yylval->data.type = SDB_TYPE_DECIMAL;
 174                 return FLOAT;
 175         }
 176
 177 {date} {
 178                 struct tm tm;
 179                 memset(&tm, 0, sizeof(tm));
 180                 if (! strptime(yytext, "%Y-%m-%d", &tm)) {
 181                         char errmsg[1024];
 182                         snprintf(errmsg, sizeof(errmsg),
 183                                 "Failed to parse '%s' as date", yytext);
 184                         sdb_fe_yyerror(yylloc, yyscanner, errmsg);
 185                         return SCANNER_ERROR;
 186                 }
 187                 yylval->datetime = SECS_TO_SDB_TIME(mktime(&tm));
 188                 return DATE;
 189         }
 190 {time} {
 191                 struct tm tm;
 192                 char time[9], ns[10];
 193                 char *tmp;
 194
 195                 memset(&tm, 0, sizeof(tm));
 196                 memset(time, '\0', sizeof(time));
 197                 memset(ns, '0', sizeof(ns));
 198                 ns[sizeof(ns) - 1] = '\0';
 199
 200                 tmp = strchr(yytext, '.');
 201                 if (tmp) {
 202                         size_t i;
 203                         *tmp = '\0';
 204                         ++tmp;
 205                         strncpy(ns, tmp, sizeof(ns));
 206                         for (i = strlen(ns); i < 9; ++i)
 207                                 ns[i] = '0';
 208                 }
 209                 strncpy(time, yytext, sizeof(time));
 210                 if (tmp) {
 211                         /* reset for better error messages */
 212                         --tmp;
 213                         *tmp = '.';
 214                 }
 215
 216                 tmp = strchr(time, ':');
 217                 assert(tmp);
 218                 tmp = strchr(tmp + 1, ':');
 219                 if (! tmp)
 220                         strncat(time, ":00", sizeof(time));
 221
 222                 if (! strptime(time, "%H:%M:%S", &tm)) {
 223                         char errmsg[1024];
 224                         snprintf(errmsg, sizeof(errmsg),
 225                                 "Failed to parse '%s' as time", yytext);
 226                         sdb_fe_yyerror(yylloc, yyscanner, errmsg);
 227                         return SCANNER_ERROR;
 228                 }
 229
 230                 yylval->datetime = SECS_TO_SDB_TIME(mktime(&tm));
 231                 yylval->datetime += (sdb_time_t)strtoll(ns, NULL, 10);
 232                 return TIME;
 233         }
 234
 235 =       { return CMP_EQUAL; }
 236 !=      { return CMP_NEQUAL; }
 237 =~      { return CMP_REGEX; }
 238 !~      { return CMP_NREGEX; }
 239 \<      { return CMP_LT; }
 240 \<=     { return CMP_LE; }
 241 \>=     { return CMP_GE; }
 242 \>      { return CMP_GT; }
 243 \|\|    { return CONCAT; }
 244
 245 .       { /* XXX: */ return yytext[0]; }
 246
 247 %%
 248
 249 sdb_fe_yyscan_t
 250 sdb_fe_scanner_init(const char *str, int len, sdb_fe_yyextra_t *yyext)
 251 {
 252         yyscan_t scanner;
 253
 254         if (! str)
 255                 return NULL;
 256
 257         if (sdb_fe_yylex_init(&scanner)) {
 258                 char errbuf[1024];
 259                 sdb_log(SDB_LOG_ERR, "frontend: yylex_init failed: %s",
 260                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 261                 return NULL;
 262         }
 263
 264         sdb_fe_yyset_extra(yyext, scanner);
 265
 266         if (len < 0)
 267                 len = strlen(str);
 268
 269         /* the newly allocated buffer state (YY_BUFFER_STATE) is stored inside the
 270          * scanner and, thus, will be freed by yylex_destroy */
 271         sdb_fe_yy_scan_bytes(str, len, scanner);
 272         return scanner;
 273 } /* sdb_fe_scanner_init */
 274
 275 void
 276 sdb_fe_scanner_destroy(sdb_fe_yyscan_t scanner)
 277 {
 278         sdb_fe_yylex_destroy(scanner);
 279 } /* sdb_fe_scanner_destroy */
 280
 281 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 282