PostgreSQL Source Code  git master
trgm_regexp.c File Reference
#include "postgres.h"
#include "regex/regexport.h"
#include "trgm.h"
#include "tsearch/ts_locale.h"
#include "utils/hsearch.h"
#include "utils/memutils.h"
Include dependency graph for trgm_regexp.c:

Go to the source code of this file.

Data Structures

struct  trgm_mb_char
 
struct  TrgmColorInfo
 
struct  TrgmPrefix
 
struct  ColorTrgm
 
struct  TrgmStateKey
 
struct  TrgmState
 
struct  TrgmArc
 
struct  TrgmArcInfo
 
struct  ColorTrgmInfo
 
struct  TrgmNFA
 
struct  TrgmPackedArc
 
struct  TrgmPackedState
 
struct  TrgmPackedGraph
 
struct  TrgmPackArcInfo
 

Macros

#define MAX_EXPANDED_STATES   128
 
#define MAX_EXPANDED_ARCS   1024
 
#define MAX_TRGM_COUNT   256
 
#define WISH_TRGM_PENALTY   16
 
#define COLOR_COUNT_LIMIT   256
 
#define COLOR_UNKNOWN   (-3)
 
#define COLOR_BLANK   (-4)
 
#define TSTATE_INIT   0x01 /* flag indicating this state is initial */
 
#define TSTATE_FIN   0x02 /* flag indicating this state is final */
 

Typedefs

typedef int TrgmColor
 
typedef struct TrgmState TrgmState
 

Functions

static TRGMcreateTrgmNFAInternal (regex_t *regex, TrgmPackedGraph **graph, MemoryContext rcontext)
 
static void RE_compile (regex_t *regex, text *text_re, int cflags, Oid collation)
 
static void getColorInfo (regex_t *regex, TrgmNFA *trgmNFA)
 
static bool convertPgWchar (pg_wchar c, trgm_mb_char *result)
 
static void transformGraph (TrgmNFA *trgmNFA)
 
static void processState (TrgmNFA *trgmNFA, TrgmState *state)
 
static void addKey (TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
 
static void addKeyToQueue (TrgmNFA *trgmNFA, TrgmStateKey *key)
 
static void addArcs (TrgmNFA *trgmNFA, TrgmState *state)
 
static void addArc (TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key, TrgmColor co, TrgmStateKey *destKey)
 
static bool validArcLabel (TrgmStateKey *key, TrgmColor co)
 
static TrgmStategetState (TrgmNFA *trgmNFA, TrgmStateKey *key)
 
static bool prefixContains (TrgmPrefix *prefix1, TrgmPrefix *prefix2)
 
static bool selectColorTrigrams (TrgmNFA *trgmNFA)
 
static TRGMexpandColorTrigrams (TrgmNFA *trgmNFA, MemoryContext rcontext)
 
static void fillTrgm (trgm *ptrgm, trgm_mb_char s[3])
 
static void mergeStates (TrgmState *state1, TrgmState *state2)
 
static int colorTrgmInfoCmp (const void *p1, const void *p2)
 
static int colorTrgmInfoPenaltyCmp (const void *p1, const void *p2)
 
static TrgmPackedGraphpackGraph (TrgmNFA *trgmNFA, MemoryContext rcontext)
 
static int packArcInfoCmp (const void *a1, const void *a2)
 
TRGMcreateTrgmNFA (text *text_re, Oid collation, TrgmPackedGraph **graph, MemoryContext rcontext)
 
bool trigramsMatchGraph (TrgmPackedGraph *graph, bool *check)
 

Variables

static const float4 penalties [8]
 

Macro Definition Documentation

◆ COLOR_BLANK

#define COLOR_BLANK   (-4)

◆ COLOR_COUNT_LIMIT

#define COLOR_COUNT_LIMIT   256

Definition at line 222 of file trgm_regexp.c.

Referenced by getColorInfo().

◆ COLOR_UNKNOWN

#define COLOR_UNKNOWN   (-3)

Definition at line 285 of file trgm_regexp.c.

Referenced by addKey(), packArcInfoCmp(), prefixContains(), transformGraph(), and validArcLabel().

◆ MAX_EXPANDED_ARCS

#define MAX_EXPANDED_ARCS   1024

Definition at line 219 of file trgm_regexp.c.

Referenced by transformGraph().

◆ MAX_EXPANDED_STATES

#define MAX_EXPANDED_STATES   128

Definition at line 218 of file trgm_regexp.c.

Referenced by transformGraph().

◆ MAX_TRGM_COUNT

#define MAX_TRGM_COUNT   256

Definition at line 220 of file trgm_regexp.c.

Referenced by selectColorTrigrams().

◆ TSTATE_FIN

#define TSTATE_FIN   0x02 /* flag indicating this state is final */

◆ TSTATE_INIT

#define TSTATE_INIT   0x01 /* flag indicating this state is initial */

Definition at line 328 of file trgm_regexp.c.

Referenced by packArcInfoCmp(), packGraph(), selectColorTrigrams(), and transformGraph().

◆ WISH_TRGM_PENALTY

#define WISH_TRGM_PENALTY   16

Definition at line 221 of file trgm_regexp.c.

Referenced by selectColorTrigrams().

Typedef Documentation

◆ TrgmColor

typedef int TrgmColor

Definition at line 282 of file trgm_regexp.c.

◆ TrgmState

typedef struct TrgmState TrgmState

Function Documentation

◆ addArc()

static void addArc ( TrgmNFA trgmNFA,
TrgmState state,
TrgmStateKey key,
TrgmColor  co,
TrgmStateKey destKey 
)
static

Definition at line 1287 of file trgm_regexp.c.

References TrgmState::arcs, TrgmNFA::arcsCount, TrgmPrefix::colors, ColorTrgm::colors, TrgmArc::ctrgm, TrgmState::enterKeys, getState(), lappend(), lfirst, TrgmStateKey::nstate, palloc(), TrgmStateKey::prefix, prefixContains(), TrgmArc::target, and validArcLabel().

Referenced by addArcs().

1289 {
1290  TrgmArc *arc;
1291  ListCell *cell;
1292 
1293  /* Do nothing if this wouldn't be a valid arc label trigram */
1294  if (!validArcLabel(key, co))
1295  return;
1296 
1297  /*
1298  * Check if we are going to reach key which is covered by a key which is
1299  * already listed in this state. If so arc is useless: the NFA can bypass
1300  * it through a path that doesn't require any predictable trigram, so
1301  * whether the arc's trigram is present or not doesn't really matter.
1302  */
1303  foreach(cell, state->enterKeys)
1304  {
1305  TrgmStateKey *existingKey = (TrgmStateKey *) lfirst(cell);
1306 
1307  if (existingKey->nstate == destKey->nstate &&
1308  prefixContains(&existingKey->prefix, &destKey->prefix))
1309  return;
1310  }
1311 
1312  /* Checks were successful, add new arc */
1313  arc = (TrgmArc *) palloc(sizeof(TrgmArc));
1314  arc->target = getState(trgmNFA, destKey);
1315  arc->ctrgm.colors[0] = key->prefix.colors[0];
1316  arc->ctrgm.colors[1] = key->prefix.colors[1];
1317  arc->ctrgm.colors[2] = co;
1318 
1319  state->arcs = lappend(state->arcs, arc);
1320  trgmNFA->arcsCount++;
1321 }
ColorTrgm ctrgm
Definition: trgm_regexp.c:348
static bool prefixContains(TrgmPrefix *prefix1, TrgmPrefix *prefix2)
Definition: trgm_regexp.c:1415
Definition: regguts.h:290
TrgmColor colors[3]
Definition: trgm_regexp.c:299
TrgmColor colors[2]
Definition: trgm_regexp.c:290
List * enterKeys
Definition: trgm_regexp.c:335
TrgmState * target
Definition: trgm_regexp.c:349
List * arcs
Definition: trgm_regexp.c:334
List * lappend(List *list, void *datum)
Definition: list.c:336
int arcsCount
Definition: trgm_regexp.c:414
#define lfirst(lc)
Definition: pg_list.h:169
static bool validArcLabel(TrgmStateKey *key, TrgmColor co)
Definition: trgm_regexp.c:1329
static TrgmState * getState(TrgmNFA *trgmNFA, TrgmStateKey *key)
Definition: trgm_regexp.c:1384
TrgmPrefix prefix
Definition: trgm_regexp.c:309
void * palloc(Size size)
Definition: mcxt.c:1062

◆ addArcs()

static void addArcs ( TrgmNFA trgmNFA,
TrgmState state 
)
static

Definition at line 1189 of file trgm_regexp.c.

References addArc(), TrgmState::arcs, Assert, regex_arc_t::co, COLOR_BLANK, TrgmNFA::colorInfo, TrgmPrefix::colors, TrgmColorInfo::containsNonWord, TrgmState::enterKeys, TrgmColorInfo::expandable, i, sort-test::key, lfirst, MemSet, TrgmNFA::ncolors, TrgmStateKey::nstate, palloc(), pfree(), pg_reg_getnumoutarcs(), pg_reg_getoutarcs(), TrgmStateKey::prefix, TrgmNFA::regex, regex_arc_t::to, and TrgmColorInfo::wordCharsCount.

Referenced by processState().

1190 {
1191  TrgmStateKey destKey;
1192  ListCell *cell;
1193  regex_arc_t *arcs;
1194  int arcsCount,
1195  i;
1196 
1197  /*
1198  * Ensure any pad bytes in destKey are zero, since it may get used as a
1199  * hashtable key by getState.
1200  */
1201  MemSet(&destKey, 0, sizeof(destKey));
1202 
1203  /*
1204  * Iterate over enter keys associated with this expanded-graph state. This
1205  * includes both the state's own stateKey, and any enter keys we added to
1206  * it during addKey (which represent expanded-graph states that are not
1207  * distinguishable from this one by means of trigrams). For each such
1208  * enter key, examine all the out-arcs of the key's underlying NFA state,
1209  * and try to make a trigram arc leading to where the out-arc leads.
1210  * (addArc will deal with whether the arc is valid or not.)
1211  */
1212  foreach(cell, state->enterKeys)
1213  {
1214  TrgmStateKey *key = (TrgmStateKey *) lfirst(cell);
1215 
1216  arcsCount = pg_reg_getnumoutarcs(trgmNFA->regex, key->nstate);
1217  arcs = (regex_arc_t *) palloc(sizeof(regex_arc_t) * arcsCount);
1218  pg_reg_getoutarcs(trgmNFA->regex, key->nstate, arcs, arcsCount);
1219 
1220  for (i = 0; i < arcsCount; i++)
1221  {
1222  regex_arc_t *arc = &arcs[i];
1223  TrgmColorInfo *colorInfo;
1224 
1225  /*
1226  * Ignore non-expandable colors; addKey already handled the case.
1227  *
1228  * We need no special check for WHITE or begin/end pseudocolors
1229  * here. We don't need to do any processing for them, and they
1230  * will be marked non-expandable since the regex engine will have
1231  * reported them that way. We do have to watch out for RAINBOW,
1232  * which has a negative color number.
1233  */
1234  if (arc->co < 0)
1235  continue;
1236  Assert(arc->co < trgmNFA->ncolors);
1237 
1238  colorInfo = &trgmNFA->colorInfo[arc->co];
1239  if (!colorInfo->expandable)
1240  continue;
1241 
1242  if (colorInfo->containsNonWord)
1243  {
1244  /*
1245  * Color includes non-word character(s).
1246  *
1247  * Generate an arc, treating this transition as occurring on
1248  * BLANK. This allows word-ending trigrams to be manufactured
1249  * if possible.
1250  */
1251  destKey.prefix.colors[0] = key->prefix.colors[1];
1252  destKey.prefix.colors[1] = COLOR_BLANK;
1253  destKey.nstate = arc->to;
1254 
1255  addArc(trgmNFA, state, key, COLOR_BLANK, &destKey);
1256  }
1257 
1258  if (colorInfo->wordCharsCount > 0)
1259  {
1260  /*
1261  * Color includes word character(s).
1262  *
1263  * Generate an arc. Color is pushed into prefix of target
1264  * state.
1265  */
1266  destKey.prefix.colors[0] = key->prefix.colors[1];
1267  destKey.prefix.colors[1] = arc->co;
1268  destKey.nstate = arc->to;
1269 
1270  addArc(trgmNFA, state, key, arc->co, &destKey);
1271  }
1272  }
1273 
1274  pfree(arcs);
1275  }
1276 }
void pg_reg_getoutarcs(const regex_t *regex, int st, regex_arc_t *arcs, int arcs_len)
Definition: regexport.c:155
static void addArc(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key, TrgmColor co, TrgmStateKey *destKey)
Definition: trgm_regexp.c:1287
TrgmColorInfo * colorInfo
Definition: trgm_regexp.c:403
regex_t * regex
Definition: trgm_regexp.c:402
Definition: regguts.h:290
#define MemSet(start, val, len)
Definition: c.h:1008
bool containsNonWord
Definition: trgm_regexp.c:261
void pfree(void *pointer)
Definition: mcxt.c:1169
TrgmColor colors[2]
Definition: trgm_regexp.c:290
List * enterKeys
Definition: trgm_regexp.c:335
#define COLOR_BLANK
Definition: trgm_regexp.c:286
int pg_reg_getnumoutarcs(const regex_t *regex, int st)
Definition: regexport.c:134
#define Assert(condition)
Definition: c.h:804
#define lfirst(lc)
Definition: pg_list.h:169
TrgmPrefix prefix
Definition: trgm_regexp.c:309
void * palloc(Size size)
Definition: mcxt.c:1062
int i
int ncolors
Definition: trgm_regexp.c:404

◆ addKey()

static void addKey ( TrgmNFA trgmNFA,
TrgmState state,
TrgmStateKey key 
)
static

Definition at line 1008 of file trgm_regexp.c.

References addKeyToQueue(), TrgmState::arcs, regex_arc_t::co, COLOR_BLANK, COLOR_UNKNOWN, TrgmNFA::colorInfo, TrgmPrefix::colors, TrgmColorInfo::containsNonWord, TrgmState::enterKeys, TrgmColorInfo::expandable, TrgmState::flags, foreach_delete_current, i, lappend(), lfirst, MemSet, TrgmStateKey::nstate, palloc(), pfree(), pg_reg_colorisbegin(), pg_reg_colorisend(), pg_reg_getfinalstate(), pg_reg_getnumoutarcs(), pg_reg_getoutarcs(), TrgmStateKey::prefix, prefixContains(), TrgmNFA::regex, regex_arc_t::to, TSTATE_FIN, validArcLabel(), and TrgmColorInfo::wordCharsCount.

Referenced by processState().

1009 {
1010  regex_arc_t *arcs;
1011  TrgmStateKey destKey;
1012  ListCell *cell;
1013  int i,
1014  arcsCount;
1015 
1016  /*
1017  * Ensure any pad bytes in destKey are zero, since it may get used as a
1018  * hashtable key by getState.
1019  */
1020  MemSet(&destKey, 0, sizeof(destKey));
1021 
1022  /*
1023  * Compare key to each existing enter key of the state to check for
1024  * redundancy. We can drop either old key(s) or the new key if we find
1025  * redundancy.
1026  */
1027  foreach(cell, state->enterKeys)
1028  {
1029  TrgmStateKey *existingKey = (TrgmStateKey *) lfirst(cell);
1030 
1031  if (existingKey->nstate == key->nstate)
1032  {
1033  if (prefixContains(&existingKey->prefix, &key->prefix))
1034  {
1035  /* This old key already covers the new key. Nothing to do */
1036  return;
1037  }
1038  if (prefixContains(&key->prefix, &existingKey->prefix))
1039  {
1040  /*
1041  * The new key covers this old key. Remove the old key, it's
1042  * no longer needed once we add this key to the list.
1043  */
1044  state->enterKeys = foreach_delete_current(state->enterKeys,
1045  cell);
1046  }
1047  }
1048  }
1049 
1050  /* No redundancy, so add this key to the state's list */
1051  state->enterKeys = lappend(state->enterKeys, key);
1052 
1053  /* If state is now known final, mark it and we're done */
1054  if (key->nstate == pg_reg_getfinalstate(trgmNFA->regex))
1055  {
1056  state->flags |= TSTATE_FIN;
1057  return;
1058  }
1059 
1060  /*
1061  * Loop through all outgoing arcs of the corresponding state in the
1062  * original NFA.
1063  */
1064  arcsCount = pg_reg_getnumoutarcs(trgmNFA->regex, key->nstate);
1065  arcs = (regex_arc_t *) palloc(sizeof(regex_arc_t) * arcsCount);
1066  pg_reg_getoutarcs(trgmNFA->regex, key->nstate, arcs, arcsCount);
1067 
1068  for (i = 0; i < arcsCount; i++)
1069  {
1070  regex_arc_t *arc = &arcs[i];
1071 
1072  if (pg_reg_colorisbegin(trgmNFA->regex, arc->co))
1073  {
1074  /*
1075  * Start of line/string (^). Trigram extraction treats start of
1076  * line same as start of word: double space prefix is added.
1077  * Hence, make an enter key showing we can reach the arc
1078  * destination with all-blank prefix.
1079  */
1080  destKey.prefix.colors[0] = COLOR_BLANK;
1081  destKey.prefix.colors[1] = COLOR_BLANK;
1082  destKey.nstate = arc->to;
1083 
1084  /* Add enter key to this state */
1085  addKeyToQueue(trgmNFA, &destKey);
1086  }
1087  else if (pg_reg_colorisend(trgmNFA->regex, arc->co))
1088  {
1089  /*
1090  * End of line/string ($). We must consider this arc as a
1091  * transition that doesn't read anything. The reason for adding
1092  * this enter key to the state is that if the arc leads to the
1093  * NFA's final state, we must mark this expanded state as final.
1094  */
1095  destKey.prefix.colors[0] = COLOR_UNKNOWN;
1096  destKey.prefix.colors[1] = COLOR_UNKNOWN;
1097  destKey.nstate = arc->to;
1098 
1099  /* Add enter key to this state */
1100  addKeyToQueue(trgmNFA, &destKey);
1101  }
1102  else if (arc->co >= 0)
1103  {
1104  /* Regular color (including WHITE) */
1105  TrgmColorInfo *colorInfo = &trgmNFA->colorInfo[arc->co];
1106 
1107  if (colorInfo->expandable)
1108  {
1109  if (colorInfo->containsNonWord &&
1110  !validArcLabel(key, COLOR_BLANK))
1111  {
1112  /*
1113  * We can reach the arc destination after reading a
1114  * non-word character, but the prefix is not something
1115  * that addArc will accept with COLOR_BLANK, so no trigram
1116  * arc can get made for this transition. We must make an
1117  * enter key to show that the arc destination is
1118  * reachable. Set it up with an all-blank prefix, since
1119  * that corresponds to what the trigram extraction code
1120  * will do at a word starting boundary.
1121  */
1122  destKey.prefix.colors[0] = COLOR_BLANK;
1123  destKey.prefix.colors[1] = COLOR_BLANK;
1124  destKey.nstate = arc->to;
1125  addKeyToQueue(trgmNFA, &destKey);
1126  }
1127 
1128  if (colorInfo->wordCharsCount > 0 &&
1129  !validArcLabel(key, arc->co))
1130  {
1131  /*
1132  * We can reach the arc destination after reading a word
1133  * character, but the prefix is not something that addArc
1134  * will accept, so no trigram arc can get made for this
1135  * transition. We must make an enter key to show that the
1136  * arc destination is reachable. The prefix for the enter
1137  * key should reflect the info we have for this arc.
1138  */
1139  destKey.prefix.colors[0] = key->prefix.colors[1];
1140  destKey.prefix.colors[1] = arc->co;
1141  destKey.nstate = arc->to;
1142  addKeyToQueue(trgmNFA, &destKey);
1143  }
1144  }
1145  else
1146  {
1147  /*
1148  * Unexpandable color. Add enter key with ambiguous prefix,
1149  * showing we can reach the destination from this state, but
1150  * the preceding colors will be uncertain. (We do not set the
1151  * first prefix color to key->prefix.colors[1], because a
1152  * prefix of known followed by unknown is invalid.)
1153  */
1154  destKey.prefix.colors[0] = COLOR_UNKNOWN;
1155  destKey.prefix.colors[1] = COLOR_UNKNOWN;
1156  destKey.nstate = arc->to;
1157  addKeyToQueue(trgmNFA, &destKey);
1158  }
1159  }
1160  else
1161  {
1162  /* RAINBOW: treat as unexpandable color */
1163  destKey.prefix.colors[0] = COLOR_UNKNOWN;
1164  destKey.prefix.colors[1] = COLOR_UNKNOWN;
1165  destKey.nstate = arc->to;
1166  addKeyToQueue(trgmNFA, &destKey);
1167  }
1168  }
1169 
1170  pfree(arcs);
1171 }
void pg_reg_getoutarcs(const regex_t *regex, int st, regex_arc_t *arcs, int arcs_len)
Definition: regexport.c:155
static bool prefixContains(TrgmPrefix *prefix1, TrgmPrefix *prefix2)
Definition: trgm_regexp.c:1415
int pg_reg_getfinalstate(const regex_t *regex)
Definition: regexport.c:64
TrgmColorInfo * colorInfo
Definition: trgm_regexp.c:403
regex_t * regex
Definition: trgm_regexp.c:402
Definition: regguts.h:290
#define MemSet(start, val, len)
Definition: c.h:1008
int pg_reg_colorisbegin(const regex_t *regex, int co)
Definition: regexport.c:191
#define TSTATE_FIN
Definition: trgm_regexp.c:329
#define foreach_delete_current(lst, cell)
Definition: pg_list.h:369
bool containsNonWord
Definition: trgm_regexp.c:261
void pfree(void *pointer)
Definition: mcxt.c:1169
TrgmColor colors[2]
Definition: trgm_regexp.c:290
List * enterKeys
Definition: trgm_regexp.c:335
List * lappend(List *list, void *datum)
Definition: list.c:336
#define COLOR_BLANK
Definition: trgm_regexp.c:286
static void addKeyToQueue(TrgmNFA *trgmNFA, TrgmStateKey *key)
Definition: trgm_regexp.c:1177
int pg_reg_colorisend(const regex_t *regex, int co)
Definition: regexport.c:208
int pg_reg_getnumoutarcs(const regex_t *regex, int st)
Definition: regexport.c:134
#define lfirst(lc)
Definition: pg_list.h:169
static bool validArcLabel(TrgmStateKey *key, TrgmColor co)
Definition: trgm_regexp.c:1329
TrgmPrefix prefix
Definition: trgm_regexp.c:309
#define COLOR_UNKNOWN
Definition: trgm_regexp.c:285
void * palloc(Size size)
Definition: mcxt.c:1062
int i

◆ addKeyToQueue()

static void addKeyToQueue ( TrgmNFA trgmNFA,
TrgmStateKey key 
)
static

Definition at line 1177 of file trgm_regexp.c.

References TrgmNFA::keysQueue, lappend(), and palloc().

Referenced by addKey().

1178 {
1179  TrgmStateKey *keyCopy = (TrgmStateKey *) palloc(sizeof(TrgmStateKey));
1180 
1181  memcpy(keyCopy, key, sizeof(TrgmStateKey));
1182  trgmNFA->keysQueue = lappend(trgmNFA->keysQueue, keyCopy);
1183 }
List * lappend(List *list, void *datum)
Definition: list.c:336
void * palloc(Size size)
Definition: mcxt.c:1062
List * keysQueue
Definition: trgm_regexp.c:413

◆ colorTrgmInfoCmp()

static int colorTrgmInfoCmp ( const void *  p1,
const void *  p2 
)
static

Definition at line 1893 of file trgm_regexp.c.

References ColorTrgmInfo::ctrgm.

Referenced by packGraph(), and selectColorTrigrams().

1894 {
1895  const ColorTrgmInfo *c1 = (const ColorTrgmInfo *) p1;
1896  const ColorTrgmInfo *c2 = (const ColorTrgmInfo *) p2;
1897 
1898  return memcmp(&c1->ctrgm, &c2->ctrgm, sizeof(ColorTrgm));
1899 }
ColorTrgm ctrgm
Definition: trgm_regexp.c:374

◆ colorTrgmInfoPenaltyCmp()

static int colorTrgmInfoPenaltyCmp ( const void *  p1,
const void *  p2 
)
static

Definition at line 1906 of file trgm_regexp.c.

Referenced by selectColorTrigrams().

1907 {
1908  float4 penalty1 = ((const ColorTrgmInfo *) p1)->penalty;
1909  float4 penalty2 = ((const ColorTrgmInfo *) p2)->penalty;
1910 
1911  if (penalty1 < penalty2)
1912  return 1;
1913  else if (penalty1 == penalty2)
1914  return 0;
1915  else
1916  return -1;
1917 }
float float4
Definition: c.h:564

◆ convertPgWchar()

static bool convertPgWchar ( pg_wchar  c,
trgm_mb_char result 
)
static

Definition at line 837 of file trgm_regexp.c.

References trgm_mb_char::bytes, lowerstr(), MAX_MULTIBYTE_CHAR_LEN, pfree(), and pg_wchar2mb_with_len().

Referenced by getColorInfo().

838 {
839  /* "s" has enough space for a multibyte character and a trailing NUL */
840  char s[MAX_MULTIBYTE_CHAR_LEN + 1];
841 
842  /*
843  * We can ignore the NUL character, since it can never appear in a PG text
844  * string. This avoids the need for various special cases when
845  * reconstructing trigrams.
846  */
847  if (c == 0)
848  return false;
849 
850  /* Do the conversion, making sure the result is NUL-terminated */
851  memset(s, 0, sizeof(s));
852  pg_wchar2mb_with_len(&c, s, 1);
853 
854  /*
855  * In IGNORECASE mode, we can ignore uppercase characters. We assume that
856  * the regex engine generated both uppercase and lowercase equivalents
857  * within each color, since we used the REG_ICASE option; so there's no
858  * need to process the uppercase version.
859  *
860  * XXX this code is dependent on the assumption that lowerstr() works the
861  * same as the regex engine's internal case folding machinery. Might be
862  * wiser to expose pg_wc_tolower and test whether c == pg_wc_tolower(c).
863  * On the other hand, the trigrams in the index were created using
864  * lowerstr(), so we're probably screwed if there's any incompatibility
865  * anyway.
866  */
867 #ifdef IGNORECASE
868  {
869  char *lowerCased = lowerstr(s);
870 
871  if (strcmp(lowerCased, s) != 0)
872  {
873  pfree(lowerCased);
874  return false;
875  }
876  pfree(lowerCased);
877  }
878 #endif
879 
880  /* Fill result with exactly MAX_MULTIBYTE_CHAR_LEN bytes */
881  memcpy(result->bytes, s, MAX_MULTIBYTE_CHAR_LEN);
882  return true;
883 }
char * lowerstr(const char *str)
Definition: ts_locale.c:244
void pfree(void *pointer)
Definition: mcxt.c:1169
char * c
#define MAX_MULTIBYTE_CHAR_LEN
Definition: pg_wchar.h:30
char bytes[MAX_MULTIBYTE_CHAR_LEN]
Definition: trgm_regexp.c:242
int pg_wchar2mb_with_len(const pg_wchar *from, char *to, int len)
Definition: mbutils.c:951

◆ createTrgmNFA()

TRGM* createTrgmNFA ( text text_re,
Oid  collation,
TrgmPackedGraph **  graph,
MemoryContext  rcontext 
)

Definition at line 521 of file trgm_regexp.c.

References ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, createTrgmNFAInternal(), CurrentMemoryContext, MemoryContextDelete(), MemoryContextSwitchTo(), PG_END_TRY, PG_FINALLY, pg_regfree(), PG_TRY, RE_compile(), REG_ADVANCED, and REG_ICASE.

Referenced by gin_extract_query_trgm(), and gtrgm_consistent().

523 {
524  TRGM *trg;
525  regex_t regex;
526  MemoryContext tmpcontext;
527  MemoryContext oldcontext;
528 
529  /*
530  * This processing generates a great deal of cruft, which we'd like to
531  * clean up before returning (since this function may be called in a
532  * query-lifespan memory context). Make a temp context we can work in so
533  * that cleanup is easy.
534  */
536  "createTrgmNFA temporary context",
538  oldcontext = MemoryContextSwitchTo(tmpcontext);
539 
540  /*
541  * Stage 1: Compile the regexp into a NFA, using the regexp library.
542  */
543 #ifdef IGNORECASE
544  RE_compile(&regex, text_re, REG_ADVANCED | REG_ICASE, collation);
545 #else
546  RE_compile(&regex, text_re, REG_ADVANCED, collation);
547 #endif
548 
549  /*
550  * Since the regexp library allocates its internal data structures with
551  * malloc, we need to use a PG_TRY block to ensure that pg_regfree() gets
552  * done even if there's an error.
553  */
554  PG_TRY();
555  {
556  trg = createTrgmNFAInternal(&regex, graph, rcontext);
557  }
558  PG_FINALLY();
559  {
560  pg_regfree(&regex);
561  }
562  PG_END_TRY();
563 
564  /* Clean up all the cruft we created */
565  MemoryContextSwitchTo(oldcontext);
566  MemoryContextDelete(tmpcontext);
567 
568  return trg;
569 }
void MemoryContextDelete(MemoryContext context)
Definition: mcxt.c:218
#define AllocSetContextCreate
Definition: memutils.h:173
static TRGM * createTrgmNFAInternal(regex_t *regex, TrgmPackedGraph **graph, MemoryContext rcontext)
Definition: trgm_regexp.c:575
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:109
#define REG_ICASE
Definition: regex.h:108
Definition: trgm.h:67
#define ALLOCSET_DEFAULT_SIZES
Definition: memutils.h:195
MemoryContext CurrentMemoryContext
Definition: mcxt.c:42
#define REG_ADVANCED
Definition: regex.h:105
#define PG_FINALLY()
Definition: elog.h:330
static void RE_compile(regex_t *regex, text *text_re, int cflags, Oid collation)
Definition: trgm_regexp.c:729
#define PG_TRY()
Definition: elog.h:313
void pg_regfree(regex_t *re)
Definition: regfree.c:49
Definition: regex.h:55
#define PG_END_TRY()
Definition: elog.h:338

◆ createTrgmNFAInternal()

static TRGM * createTrgmNFAInternal ( regex_t regex,
TrgmPackedGraph **  graph,
MemoryContext  rcontext 
)
static

Definition at line 575 of file trgm_regexp.c.

References TrgmNFA::colorInfo, expandColorTrigrams(), TrgmState::flags, getColorInfo(), TrgmNFA::initState, TrgmNFA::ncolors, packGraph(), TrgmNFA::regex, selectColorTrigrams(), transformGraph(), and TSTATE_FIN.

Referenced by createTrgmNFA().

577 {
578  TRGM *trg;
579  TrgmNFA trgmNFA;
580 
581  trgmNFA.regex = regex;
582 
583  /* Collect color information from the regex */
584  getColorInfo(regex, &trgmNFA);
585 
586 #ifdef TRGM_REGEXP_DEBUG
587  printSourceNFA(regex, trgmNFA.colorInfo, trgmNFA.ncolors);
588 #endif
589 
590  /*
591  * Stage 2: Create an expanded graph from the source NFA.
592  */
593  transformGraph(&trgmNFA);
594 
595 #ifdef TRGM_REGEXP_DEBUG
596  printTrgmNFA(&trgmNFA);
597 #endif
598 
599  /*
600  * Fail if we were unable to make a nontrivial graph, ie it is possible to
601  * get from the initial state to the final state without reading any
602  * predictable trigram.
603  */
604  if (trgmNFA.initState->flags & TSTATE_FIN)
605  return NULL;
606 
607  /*
608  * Stage 3: Select color trigrams to expand. Fail if too many trigrams.
609  */
610  if (!selectColorTrigrams(&trgmNFA))
611  return NULL;
612 
613  /*
614  * Stage 4: Expand color trigrams and pack graph into final
615  * representation.
616  */
617  trg = expandColorTrigrams(&trgmNFA, rcontext);
618 
619  *graph = packGraph(&trgmNFA, rcontext);
620 
621 #ifdef TRGM_REGEXP_DEBUG
622  printTrgmPackedGraph(*graph, trg);
623 #endif
624 
625  return trg;
626 }
static void getColorInfo(regex_t *regex, TrgmNFA *trgmNFA)
Definition: trgm_regexp.c:773
TrgmColorInfo * colorInfo
Definition: trgm_regexp.c:403
regex_t * regex
Definition: trgm_regexp.c:402
TrgmState * initState
Definition: trgm_regexp.c:408
#define TSTATE_FIN
Definition: trgm_regexp.c:329
static bool selectColorTrigrams(TrgmNFA *trgmNFA)
Definition: trgm_regexp.c:1457
Definition: trgm.h:67
static TrgmPackedGraph * packGraph(TrgmNFA *trgmNFA, MemoryContext rcontext)
Definition: trgm_regexp.c:1931
static TRGM * expandColorTrigrams(TrgmNFA *trgmNFA, MemoryContext rcontext)
Definition: trgm_regexp.c:1776
static void transformGraph(TrgmNFA *trgmNFA)
Definition: trgm_regexp.c:903
int ncolors
Definition: trgm_regexp.c:404

◆ expandColorTrigrams()

static TRGM * expandColorTrigrams ( TrgmNFA trgmNFA,
MemoryContext  rcontext 
)
static

Definition at line 1776 of file trgm_regexp.c.

References ARRKEY, trgm_mb_char::bytes, CALCGTSIZE, COLOR_BLANK, TrgmNFA::colorInfo, ColorTrgm::colors, TrgmNFA::colorTrgms, TrgmNFA::colorTrgmsCount, ColorTrgmInfo::ctrgm, ColorTrgmInfo::expanded, fillTrgm(), TRGM::flag, GETARR, i, MemoryContextAllocZero(), SET_VARSIZE, TrgmNFA::totalTrgmCount, TRGMHDRSIZE, TrgmColorInfo::wordChars, and TrgmColorInfo::wordCharsCount.

Referenced by createTrgmNFAInternal().

1777 {
1778  TRGM *trg;
1779  trgm *p;
1780  int i;
1781  TrgmColorInfo blankColor;
1782  trgm_mb_char blankChar;
1783 
1784  /* Set up "blank" color structure containing a single zero character */
1785  memset(blankChar.bytes, 0, sizeof(blankChar.bytes));
1786  blankColor.wordCharsCount = 1;
1787  blankColor.wordChars = &blankChar;
1788 
1789  /* Construct the trgm array */
1790  trg = (TRGM *)
1791  MemoryContextAllocZero(rcontext,
1792  TRGMHDRSIZE +
1793  trgmNFA->totalTrgmCount * sizeof(trgm));
1794  trg->flag = ARRKEY;
1795  SET_VARSIZE(trg, CALCGTSIZE(ARRKEY, trgmNFA->totalTrgmCount));
1796  p = GETARR(trg);
1797  for (i = 0; i < trgmNFA->colorTrgmsCount; i++)
1798  {
1799  ColorTrgmInfo *colorTrgm = &trgmNFA->colorTrgms[i];
1800  TrgmColorInfo *c[3];
1801  trgm_mb_char s[3];
1802  int j,
1803  i1,
1804  i2,
1805  i3;
1806 
1807  /* Ignore any unexpanded trigrams ... */
1808  if (!colorTrgm->expanded)
1809  continue;
1810 
1811  /* Get colors, substituting the dummy struct for COLOR_BLANK */
1812  for (j = 0; j < 3; j++)
1813  {
1814  if (colorTrgm->ctrgm.colors[j] != COLOR_BLANK)
1815  c[j] = &trgmNFA->colorInfo[colorTrgm->ctrgm.colors[j]];
1816  else
1817  c[j] = &blankColor;
1818  }
1819 
1820  /* Iterate over all possible combinations of colors' characters */
1821  for (i1 = 0; i1 < c[0]->wordCharsCount; i1++)
1822  {
1823  s[0] = c[0]->wordChars[i1];
1824  for (i2 = 0; i2 < c[1]->wordCharsCount; i2++)
1825  {
1826  s[1] = c[1]->wordChars[i2];
1827  for (i3 = 0; i3 < c[2]->wordCharsCount; i3++)
1828  {
1829  s[2] = c[2]->wordChars[i3];
1830  fillTrgm(p, s);
1831  p++;
1832  }
1833  }
1834  }
1835  }
1836 
1837  return trg;
1838 }
TrgmColorInfo * colorInfo
Definition: trgm_regexp.c:403
TrgmColor colors[3]
Definition: trgm_regexp.c:299
#define ARRKEY
Definition: trgm.h:97
int totalTrgmCount
Definition: trgm_regexp.c:420
#define CALCGTSIZE(flag, siglen)
Definition: hstore_gist.c:59
#define GETARR(x)
Definition: trgm.h:107
Definition: trgm.h:67
char * c
ColorTrgmInfo * colorTrgms
Definition: trgm_regexp.c:418
#define TRGMHDRSIZE
Definition: trgm.h:74
#define COLOR_BLANK
Definition: trgm_regexp.c:286
uint8 flag
Definition: trgm.h:70
void * MemoryContextAllocZero(MemoryContext context, Size size)
Definition: mcxt.c:906
int colorTrgmsCount
Definition: trgm_regexp.c:419
char trgm[3]
Definition: trgm.h:42
char bytes[MAX_MULTIBYTE_CHAR_LEN]
Definition: trgm_regexp.c:242
int i
ColorTrgm ctrgm
Definition: trgm_regexp.c:374
#define SET_VARSIZE(PTR, len)
Definition: postgres.h:342
trgm_mb_char * wordChars
Definition: trgm_regexp.c:263
static void fillTrgm(trgm *ptrgm, trgm_mb_char s[3])
Definition: trgm_regexp.c:1844

◆ fillTrgm()

static void fillTrgm ( trgm ptrgm,
trgm_mb_char  s[3] 
)
static

Definition at line 1844 of file trgm_regexp.c.

References generate_unaccent_rules::bytes(), trgm_mb_char::bytes, compact_trigram(), i, MAX_MULTIBYTE_CHAR_LEN, and generate_unaccent_rules::str.

Referenced by expandColorTrigrams().

1845 {
1846  char str[3 * MAX_MULTIBYTE_CHAR_LEN],
1847  *p;
1848  int i,
1849  j;
1850 
1851  /* Write multibyte string into "str" (we don't need null termination) */
1852  p = str;
1853 
1854  for (i = 0; i < 3; i++)
1855  {
1856  if (s[i].bytes[0] != 0)
1857  {
1858  for (j = 0; j < MAX_MULTIBYTE_CHAR_LEN && s[i].bytes[j]; j++)
1859  *p++ = s[i].bytes[j];
1860  }
1861  else
1862  {
1863  /* Emit a space in place of COLOR_BLANK */
1864  *p++ = ' ';
1865  }
1866  }
1867 
1868  /* Convert "str" to a standard trigram (possibly hashing it) */
1869  compact_trigram(ptrgm, str, p - str);
1870 }
def bytes(source, encoding='ascii', errors='strict')
#define MAX_MULTIBYTE_CHAR_LEN
Definition: pg_wchar.h:30
void compact_trigram(trgm *tptr, char *str, int bytelen)
Definition: trgm_op.c:198
char bytes[MAX_MULTIBYTE_CHAR_LEN]
Definition: trgm_regexp.c:242
int i

◆ getColorInfo()

static void getColorInfo ( regex_t regex,
TrgmNFA trgmNFA 
)
static

Definition at line 773 of file trgm_regexp.c.

References trgm_mb_char::bytes, chars, COLOR_COUNT_LIMIT, TrgmNFA::colorInfo, TrgmColorInfo::containsNonWord, convertPgWchar(), TrgmColorInfo::expandable, i, ISWORDCHR, TrgmNFA::ncolors, palloc(), palloc0(), pfree(), pg_reg_getcharacters(), pg_reg_getnumcharacters(), pg_reg_getnumcolors(), TrgmColorInfo::wordChars, and TrgmColorInfo::wordCharsCount.

Referenced by createTrgmNFAInternal().

774 {
775  int colorsCount = pg_reg_getnumcolors(regex);
776  int i;
777 
778  trgmNFA->ncolors = colorsCount;
779  trgmNFA->colorInfo = (TrgmColorInfo *)
780  palloc0(colorsCount * sizeof(TrgmColorInfo));
781 
782  /*
783  * Loop over colors, filling TrgmColorInfo about each. Note we include
784  * WHITE (0) even though we know it'll be reported as non-expandable.
785  */
786  for (i = 0; i < colorsCount; i++)
787  {
788  TrgmColorInfo *colorInfo = &trgmNFA->colorInfo[i];
789  int charsCount = pg_reg_getnumcharacters(regex, i);
790  pg_wchar *chars;
791  int j;
792 
793  if (charsCount < 0 || charsCount > COLOR_COUNT_LIMIT)
794  {
795  /* Non expandable, or too large to work with */
796  colorInfo->expandable = false;
797  continue;
798  }
799 
800  colorInfo->expandable = true;
801  colorInfo->containsNonWord = false;
802  colorInfo->wordChars = (trgm_mb_char *)
803  palloc(sizeof(trgm_mb_char) * charsCount);
804  colorInfo->wordCharsCount = 0;
805 
806  /* Extract all the chars in this color */
807  chars = (pg_wchar *) palloc(sizeof(pg_wchar) * charsCount);
808  pg_reg_getcharacters(regex, i, chars, charsCount);
809 
810  /*
811  * Convert characters back to multibyte form, and save only those that
812  * are word characters. Set "containsNonWord" if any non-word
813  * character. (Note: it'd probably be nicer to keep the chars in
814  * pg_wchar format for now, but ISWORDCHR wants to see multibyte.)
815  */
816  for (j = 0; j < charsCount; j++)
817  {
818  trgm_mb_char c;
819 
820  if (!convertPgWchar(chars[j], &c))
821  continue; /* ok to ignore it altogether */
822  if (ISWORDCHR(c.bytes))
823  colorInfo->wordChars[colorInfo->wordCharsCount++] = c;
824  else
825  colorInfo->containsNonWord = true;
826  }
827 
828  pfree(chars);
829  }
830 }
TrgmColorInfo * colorInfo
Definition: trgm_regexp.c:403
int pg_reg_getnumcharacters(const regex_t *regex, int co)
Definition: regexport.c:230
void pg_reg_getcharacters(const regex_t *regex, int co, pg_wchar *chars, int chars_len)
Definition: regexport.c:266
#define ISWORDCHR(c)
Definition: trgm.h:55
int pg_reg_getnumcolors(const regex_t *regex)
Definition: regexport.c:174
bool containsNonWord
Definition: trgm_regexp.c:261
static bool convertPgWchar(pg_wchar c, trgm_mb_char *result)
Definition: trgm_regexp.c:837
void pfree(void *pointer)
Definition: mcxt.c:1169
char * c
#define COLOR_COUNT_LIMIT
Definition: trgm_regexp.c:222
unsigned int pg_wchar
Definition: mbprint.c:31
void * palloc0(Size size)
Definition: mcxt.c:1093
char bytes[MAX_MULTIBYTE_CHAR_LEN]
Definition: trgm_regexp.c:242
void * palloc(Size size)
Definition: mcxt.c:1062
int i
trgm_mb_char * wordChars
Definition: trgm_regexp.c:263
static char chars[TZ_MAX_CHARS]
Definition: zic.c:399
int ncolors
Definition: trgm_regexp.c:404

◆ getState()

static TrgmState * getState ( TrgmNFA trgmNFA,
TrgmStateKey key 
)
static

Definition at line 1384 of file trgm_regexp.c.

References TrgmState::arcs, TrgmState::enterKeys, TrgmState::flags, HASH_ENTER, hash_search(), lappend(), NIL, TrgmNFA::nstates, TrgmState::parent, TrgmNFA::queue, TrgmState::snumber, TrgmNFA::states, TrgmState::tentFlags, and TrgmState::tentParent.

Referenced by addArc(), and transformGraph().

1385 {
1386  TrgmState *state;
1387  bool found;
1388 
1389  state = (TrgmState *) hash_search(trgmNFA->states, key, HASH_ENTER,
1390  &found);
1391  if (!found)
1392  {
1393  /* New state: initialize and queue it */
1394  state->arcs = NIL;
1395  state->enterKeys = NIL;
1396  state->flags = 0;
1397  /* states are initially given negative numbers */
1398  state->snumber = -(++trgmNFA->nstates);
1399  state->parent = NULL;
1400  state->tentFlags = 0;
1401  state->tentParent = NULL;
1402 
1403  trgmNFA->queue = lappend(trgmNFA->queue, state);
1404  }
1405  return state;
1406 }
#define NIL
Definition: pg_list.h:65
struct TrgmState * tentParent
Definition: trgm_regexp.c:340
HTAB * states
Definition: trgm_regexp.c:407
void * hash_search(HTAB *hashp, const void *keyPtr, HASHACTION action, bool *foundPtr)
Definition: dynahash.c:954
int nstates
Definition: trgm_regexp.c:409
List * enterKeys
Definition: trgm_regexp.c:335
List * arcs
Definition: trgm_regexp.c:334
List * lappend(List *list, void *datum)
Definition: list.c:336
List * queue
Definition: trgm_regexp.c:412
int tentFlags
Definition: trgm_regexp.c:339
Definition: regguts.h:317
struct TrgmState * parent
Definition: trgm_regexp.c:338

◆ mergeStates()

static void mergeStates ( TrgmState state1,
TrgmState state2 
)
static

Definition at line 1876 of file trgm_regexp.c.

References Assert, TrgmState::flags, and TrgmState::parent.

Referenced by selectColorTrigrams().

1877 {
1878  Assert(state1 != state2);
1879  Assert(!state1->parent);
1880  Assert(!state2->parent);
1881 
1882  /* state1 absorbs state2's flags */
1883  state1->flags |= state2->flags;
1884 
1885  /* state2, and indirectly all its children, become children of state1 */
1886  state2->parent = state1;
1887 }
#define Assert(condition)
Definition: c.h:804
struct TrgmState * parent
Definition: trgm_regexp.c:338

◆ packArcInfoCmp()

static int packArcInfoCmp ( const void *  a1,
const void *  a2 
)
static

Definition at line 2086 of file trgm_regexp.c.

References appendStringInfo(), appendStringInfoChar(), appendStringInfoString(), TrgmState::arcs, TrgmPackedState::arcs, TrgmPackedState::arcsCount, buf, trgm_mb_char::bytes, COLOR_BLANK, COLOR_UNKNOWN, ColorTrgm::colors, TrgmPackedArc::colorTrgm, TrgmPackArcInfo::colorTrgm, TrgmPackedGraph::colorTrigramGroups, TrgmPackedGraph::colorTrigramsCount, TrgmArc::ctrgm, StringInfoData::data, TrgmColorInfo::expandable, TrgmState::flags, fprintf, GETARR, hash_seq_init(), hash_seq_search(), i, initStringInfo(), lfirst, MAX_MULTIBYTE_CHAR_LEN, TrgmStateKey::nstate, palloc(), pfree(), pg_reg_getfinalstate(), pg_reg_getinitialstate(), pg_reg_getnumoutarcs(), pg_reg_getnumstates(), pg_reg_getoutarcs(), TrgmState::snumber, TrgmPackArcInfo::sourceState, TrgmState::stateKey, TrgmNFA::states, TrgmPackedGraph::states, TrgmPackedGraph::statesCount, TrgmArc::target, TrgmPackedArc::targetState, TrgmPackArcInfo::targetState, TSTATE_FIN, TSTATE_INIT, TrgmColorInfo::wordChars, and TrgmColorInfo::wordCharsCount.

Referenced by packGraph().

2087 {
2088  const TrgmPackArcInfo *p1 = (const TrgmPackArcInfo *) a1;
2089  const TrgmPackArcInfo *p2 = (const TrgmPackArcInfo *) a2;
2090 
2091  if (p1->sourceState < p2->sourceState)
2092  return -1;
2093  if (p1->sourceState > p2->sourceState)
2094  return 1;
2095  if (p1->colorTrgm < p2->colorTrgm)
2096  return -1;
2097  if (p1->colorTrgm > p2->colorTrgm)
2098  return 1;
2099  if (p1->targetState < p2->targetState)
2100  return -1;
2101  if (p1->targetState > p2->targetState)
2102  return 1;
2103  return 0;
2104 }
static const FormData_pg_attribute a2
Definition: heap.c:166
static const FormData_pg_attribute a1
Definition: heap.c:152

◆ packGraph()

static TrgmPackedGraph * packGraph ( TrgmNFA trgmNFA,
MemoryContext  rcontext 
)
static

Definition at line 1931 of file trgm_regexp.c.

References TrgmState::arcs, TrgmPackedState::arcs, TrgmNFA::arcsCount, TrgmPackedState::arcsCount, Assert, ColorTrgmInfo::cnumber, TrgmPackedArc::colorTrgm, TrgmPackArcInfo::colorTrgm, colorTrgmInfoCmp(), TrgmNFA::colorTrgms, TrgmNFA::colorTrgmsCount, TrgmPackedGraph::colorTrigramGroups, TrgmPackedGraph::colorTrigramsActive, TrgmPackedGraph::colorTrigramsCount, ColorTrgmInfo::count, TrgmArc::ctrgm, ColorTrgmInfo::expanded, TrgmState::flags, hash_seq_init(), hash_seq_search(), i, lfirst, MemoryContextAlloc(), packArcInfoCmp(), palloc(), TrgmState::parent, qsort, TrgmState::snumber, source, TrgmPackArcInfo::sourceState, TrgmNFA::states, TrgmPackedGraph::states, TrgmPackedGraph::statesActive, TrgmPackedGraph::statesCount, TrgmPackedGraph::statesQueue, TrgmArc::target, TrgmPackedArc::targetState, TrgmPackArcInfo::targetState, TSTATE_FIN, and TSTATE_INIT.

Referenced by createTrgmNFAInternal().

1932 {
1933  int snumber = 2,
1934  arcIndex,
1935  arcsCount;
1936  HASH_SEQ_STATUS scan_status;
1937  TrgmState *state;
1938  TrgmPackArcInfo *arcs,
1939  *p1,
1940  *p2;
1941  TrgmPackedArc *packedArcs;
1942  TrgmPackedGraph *result;
1943  int i,
1944  j;
1945 
1946  /* Enumerate surviving states, giving init and fin reserved numbers */
1947  hash_seq_init(&scan_status, trgmNFA->states);
1948  while ((state = (TrgmState *) hash_seq_search(&scan_status)) != NULL)
1949  {
1950  while (state->parent)
1951  state = state->parent;
1952 
1953  if (state->snumber < 0)
1954  {
1955  if (state->flags & TSTATE_INIT)
1956  state->snumber = 0;
1957  else if (state->flags & TSTATE_FIN)
1958  state->snumber = 1;
1959  else
1960  {
1961  state->snumber = snumber;
1962  snumber++;
1963  }
1964  }
1965  }
1966 
1967  /* Collect array of all arcs */
1968  arcs = (TrgmPackArcInfo *)
1969  palloc(sizeof(TrgmPackArcInfo) * trgmNFA->arcsCount);
1970  arcIndex = 0;
1971  hash_seq_init(&scan_status, trgmNFA->states);
1972  while ((state = (TrgmState *) hash_seq_search(&scan_status)) != NULL)
1973  {
1974  TrgmState *source = state;
1975  ListCell *cell;
1976 
1977  while (source->parent)
1978  source = source->parent;
1979 
1980  foreach(cell, state->arcs)
1981  {
1982  TrgmArc *arc = (TrgmArc *) lfirst(cell);
1983  TrgmState *target = arc->target;
1984 
1985  while (target->parent)
1986  target = target->parent;
1987 
1988  if (source->snumber != target->snumber)
1989  {
1990  ColorTrgmInfo *ctrgm;
1991 
1992  ctrgm = (ColorTrgmInfo *) bsearch(&arc->ctrgm,
1993  trgmNFA->colorTrgms,
1994  trgmNFA->colorTrgmsCount,
1995  sizeof(ColorTrgmInfo),
1997  Assert(ctrgm != NULL);
1998  Assert(ctrgm->expanded);
1999 
2000  arcs[arcIndex].sourceState = source->snumber;
2001  arcs[arcIndex].targetState = target->snumber;
2002  arcs[arcIndex].colorTrgm = ctrgm->cnumber;
2003  arcIndex++;
2004  }
2005  }
2006  }
2007 
2008  /* Sort arcs to ease duplicate detection */
2009  qsort(arcs, arcIndex, sizeof(TrgmPackArcInfo), packArcInfoCmp);
2010 
2011  /* We could have duplicates because states were merged. Remove them. */
2012  /* p1 is probe point, p2 is last known non-duplicate. */
2013  p2 = arcs;
2014  for (p1 = arcs + 1; p1 < arcs + arcIndex; p1++)
2015  {
2016  if (packArcInfoCmp(p1, p2) > 0)
2017  {
2018  p2++;
2019  *p2 = *p1;
2020  }
2021  }
2022  arcsCount = (p2 - arcs) + 1;
2023 
2024  /* Create packed representation */
2025  result = (TrgmPackedGraph *)
2026  MemoryContextAlloc(rcontext, sizeof(TrgmPackedGraph));
2027 
2028  /* Pack color trigrams information */
2029  result->colorTrigramsCount = 0;
2030  for (i = 0; i < trgmNFA->colorTrgmsCount; i++)
2031  {
2032  if (trgmNFA->colorTrgms[i].expanded)
2033  result->colorTrigramsCount++;
2034  }
2035  result->colorTrigramGroups = (int *)
2036  MemoryContextAlloc(rcontext, sizeof(int) * result->colorTrigramsCount);
2037  j = 0;
2038  for (i = 0; i < trgmNFA->colorTrgmsCount; i++)
2039  {
2040  if (trgmNFA->colorTrgms[i].expanded)
2041  {
2042  result->colorTrigramGroups[j] = trgmNFA->colorTrgms[i].count;
2043  j++;
2044  }
2045  }
2046 
2047  /* Pack states and arcs information */
2048  result->statesCount = snumber;
2049  result->states = (TrgmPackedState *)
2050  MemoryContextAlloc(rcontext, snumber * sizeof(TrgmPackedState));
2051  packedArcs = (TrgmPackedArc *)
2052  MemoryContextAlloc(rcontext, arcsCount * sizeof(TrgmPackedArc));
2053  j = 0;
2054  for (i = 0; i < snumber; i++)
2055  {
2056  int cnt = 0;
2057 
2058  result->states[i].arcs = &packedArcs[j];
2059  while (j < arcsCount && arcs[j].sourceState == i)
2060  {
2061  packedArcs[j].targetState = arcs[j].targetState;
2062  packedArcs[j].colorTrgm = arcs[j].colorTrgm;
2063  cnt++;
2064  j++;
2065  }
2066  result->states[i].arcsCount = cnt;
2067  }
2068 
2069  /* Allocate working memory for trigramsMatchGraph() */
2070  result->colorTrigramsActive = (bool *)
2071  MemoryContextAlloc(rcontext, sizeof(bool) * result->colorTrigramsCount);
2072  result->statesActive = (bool *)
2073  MemoryContextAlloc(rcontext, sizeof(bool) * result->statesCount);
2074  result->statesQueue = (int *)
2075  MemoryContextAlloc(rcontext, sizeof(int) * result->statesCount);
2076 
2077  return result;
2078 }
bool * colorTrigramsActive
Definition: trgm_regexp.c:461
ColorTrgm ctrgm
Definition: trgm_regexp.c:348
Definition: regguts.h:290
HTAB * states
Definition: trgm_regexp.c:407
TrgmPackedState * states
Definition: trgm_regexp.c:458
#define TSTATE_FIN
Definition: trgm_regexp.c:329
#define TSTATE_INIT
Definition: trgm_regexp.c:328
TrgmPackedArc * arcs
Definition: trgm_regexp.c:435
static int packArcInfoCmp(const void *a1, const void *a2)
Definition: trgm_regexp.c:2086
bool * statesActive
Definition: trgm_regexp.c:462
ColorTrgmInfo * colorTrgms
Definition: trgm_regexp.c:418
TrgmState * target
Definition: trgm_regexp.c:349
List * arcs
Definition: trgm_regexp.c:334
int arcsCount
Definition: trgm_regexp.c:414
int colorTrgmsCount
Definition: trgm_regexp.c:419
#define Assert(condition)
Definition: c.h:804
#define lfirst(lc)
Definition: pg_list.h:169
Definition: regguts.h:317
static rewind_source * source
Definition: pg_rewind.c:79
void * hash_seq_search(HASH_SEQ_STATUS *status)
Definition: dynahash.c:1436
void hash_seq_init(HASH_SEQ_STATUS *status, HTAB *hashp)
Definition: dynahash.c:1426
static int colorTrgmInfoCmp(const void *p1, const void *p2)
Definition: trgm_regexp.c:1893
struct TrgmState * parent
Definition: trgm_regexp.c:338
void * palloc(Size size)
Definition: mcxt.c:1062
void * MemoryContextAlloc(MemoryContext context, Size size)
Definition: mcxt.c:863
int i
#define qsort(a, b, c, d)
Definition: port.h:504
int * colorTrigramGroups
Definition: trgm_regexp.c:451

◆ prefixContains()

static bool prefixContains ( TrgmPrefix prefix1,
TrgmPrefix prefix2 
)
static

Definition at line 1415 of file trgm_regexp.c.

References COLOR_UNKNOWN, and TrgmPrefix::colors.

Referenced by addArc(), and addKey().

1416 {
1417  if (prefix1->colors[1] == COLOR_UNKNOWN)
1418  {
1419  /* Fully ambiguous prefix contains everything */
1420  return true;
1421  }
1422  else if (prefix1->colors[0] == COLOR_UNKNOWN)
1423  {
1424  /*
1425  * Prefix with only first unknown color contains every prefix with
1426  * same second color.
1427  */
1428  if (prefix1->colors[1] == prefix2->colors[1])
1429  return true;
1430  else
1431  return false;
1432  }
1433  else
1434  {
1435  /* Exact prefix contains only the exact same prefix */
1436  if (prefix1->colors[0] == prefix2->colors[0] &&
1437  prefix1->colors[1] == prefix2->colors[1])
1438  return true;
1439  else
1440  return false;
1441  }
1442 }
TrgmColor colors[2]
Definition: trgm_regexp.c:290
#define COLOR_UNKNOWN
Definition: trgm_regexp.c:285

◆ processState()

static void processState ( TrgmNFA trgmNFA,
TrgmState state 
)
static

Definition at line 965 of file trgm_regexp.c.

References addArcs(), addKey(), TrgmState::flags, sort-test::key, TrgmNFA::keysQueue, linitial, list_delete_first(), NIL, TrgmState::stateKey, and TSTATE_FIN.

Referenced by transformGraph().

966 {
967  /* keysQueue should be NIL already, but make sure */
968  trgmNFA->keysQueue = NIL;
969 
970  /*
971  * Add state's own key, and then process all keys added to keysQueue until
972  * queue is empty. But we can quit if the state gets marked final.
973  */
974  addKey(trgmNFA, state, &state->stateKey);
975  while (trgmNFA->keysQueue != NIL && !(state->flags & TSTATE_FIN))
976  {
978 
979  trgmNFA->keysQueue = list_delete_first(trgmNFA->keysQueue);
980  addKey(trgmNFA, state, key);
981  }
982 
983  /*
984  * Add outgoing arcs only if state isn't final (we have no interest in
985  * outgoing arcs if we already match)
986  */
987  if (!(state->flags & TSTATE_FIN))
988  addArcs(trgmNFA, state);
989 }
#define NIL
Definition: pg_list.h:65
static void addKey(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
Definition: trgm_regexp.c:1008
#define TSTATE_FIN
Definition: trgm_regexp.c:329
#define linitial(l)
Definition: pg_list.h:174
TrgmStateKey stateKey
Definition: trgm_regexp.c:333
static void addArcs(TrgmNFA *trgmNFA, TrgmState *state)
Definition: trgm_regexp.c:1189
List * keysQueue
Definition: trgm_regexp.c:413
List * list_delete_first(List *list)
Definition: list.c:875

◆ RE_compile()

static void RE_compile ( regex_t regex,
text text_re,
int  cflags,
Oid  collation 
)
static

Definition at line 729 of file trgm_regexp.c.

References ereport, errcode(), errmsg(), ERROR, palloc(), pfree(), pg_mb2wchar_with_len(), pg_regcomp(), pg_regerror(), REG_OKAY, VARDATA_ANY, and VARSIZE_ANY_EXHDR.

Referenced by createTrgmNFA().

730 {
731  int text_re_len = VARSIZE_ANY_EXHDR(text_re);
732  char *text_re_val = VARDATA_ANY(text_re);
733  pg_wchar *pattern;
734  int pattern_len;
735  int regcomp_result;
736  char errMsg[100];
737 
738  /* Convert pattern string to wide characters */
739  pattern = (pg_wchar *) palloc((text_re_len + 1) * sizeof(pg_wchar));
740  pattern_len = pg_mb2wchar_with_len(text_re_val,
741  pattern,
742  text_re_len);
743 
744  /* Compile regex */
745  regcomp_result = pg_regcomp(regex,
746  pattern,
747  pattern_len,
748  cflags,
749  collation);
750 
751  pfree(pattern);
752 
753  if (regcomp_result != REG_OKAY)
754  {
755  /* re didn't compile (no need for pg_regfree, if so) */
756  pg_regerror(regcomp_result, regex, errMsg, sizeof(errMsg));
757  ereport(ERROR,
758  (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
759  errmsg("invalid regular expression: %s", errMsg)));
760  }
761 }
#define VARDATA_ANY(PTR)
Definition: postgres.h:361
int errcode(int sqlerrcode)
Definition: elog.c:698
int pg_regcomp(regex_t *re, const chr *string, size_t len, int flags, Oid collation)
Definition: regcomp.c:328
void pfree(void *pointer)
Definition: mcxt.c:1169
#define REG_OKAY
Definition: regex.h:139
#define ERROR
Definition: elog.h:46
size_t pg_regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
Definition: regerror.c:60
unsigned int pg_wchar
Definition: mbprint.c:31
int pg_mb2wchar_with_len(const char *from, pg_wchar *to, int len)
Definition: mbutils.c:929
#define ereport(elevel,...)
Definition: elog.h:157
#define VARSIZE_ANY_EXHDR(PTR)
Definition: postgres.h:354
void * palloc(Size size)
Definition: mcxt.c:1062
int errmsg(const char *fmt,...)
Definition: elog.c:909

◆ selectColorTrigrams()

static bool selectColorTrigrams ( TrgmNFA trgmNFA)
static

Definition at line 1457 of file trgm_regexp.c.

References TrgmState::arcs, ColorTrgmInfo::arcs, TrgmNFA::arcsCount, Assert, ColorTrgmInfo::cnumber, COLOR_BLANK, TrgmNFA::colorInfo, ColorTrgm::colors, colorTrgmInfoCmp(), colorTrgmInfoPenaltyCmp(), TrgmNFA::colorTrgms, TrgmNFA::colorTrgmsCount, ColorTrgmInfo::count, TrgmArc::ctrgm, ColorTrgmInfo::ctrgm, ColorTrgmInfo::expanded, TrgmState::flags, fprintf, hash_seq_init(), hash_seq_search(), i, lfirst, list_concat(), list_length(), list_make1, MAX_TRGM_COUNT, mergeStates(), palloc(), palloc0(), TrgmState::parent, penalties, ColorTrgmInfo::penalty, qsort, TrgmState::snumber, source, TrgmArcInfo::source, TrgmNFA::states, TrgmArc::target, TrgmArcInfo::target, TrgmState::tentFlags, TrgmState::tentParent, TrgmNFA::totalTrgmCount, TSTATE_FIN, TSTATE_INIT, WISH_TRGM_PENALTY, and TrgmColorInfo::wordCharsCount.

Referenced by createTrgmNFAInternal().

1458 {
1459  HASH_SEQ_STATUS scan_status;
1460  int arcsCount = trgmNFA->arcsCount,
1461  i;
1462  TrgmState *state;
1463  ColorTrgmInfo *colorTrgms;
1464  int64 totalTrgmCount;
1465  float4 totalTrgmPenalty;
1466  int cnumber;
1467 
1468  /* Collect color trigrams from all arcs */
1469  colorTrgms = (ColorTrgmInfo *) palloc0(sizeof(ColorTrgmInfo) * arcsCount);
1470  trgmNFA->colorTrgms = colorTrgms;
1471 
1472  i = 0;
1473  hash_seq_init(&scan_status, trgmNFA->states);
1474  while ((state = (TrgmState *) hash_seq_search(&scan_status)) != NULL)
1475  {
1476  ListCell *cell;
1477 
1478  foreach(cell, state->arcs)
1479  {
1480  TrgmArc *arc = (TrgmArc *) lfirst(cell);
1481  TrgmArcInfo *arcInfo = (TrgmArcInfo *) palloc(sizeof(TrgmArcInfo));
1482  ColorTrgmInfo *trgmInfo = &colorTrgms[i];
1483 
1484  arcInfo->source = state;
1485  arcInfo->target = arc->target;
1486  trgmInfo->ctrgm = arc->ctrgm;
1487  trgmInfo->cnumber = -1;
1488  /* count and penalty will be set below */
1489  trgmInfo->expanded = true;
1490  trgmInfo->arcs = list_make1(arcInfo);
1491  i++;
1492  }
1493  }
1494  Assert(i == arcsCount);
1495 
1496  /* Remove duplicates, merging their arcs lists */
1497  if (arcsCount >= 2)
1498  {
1499  ColorTrgmInfo *p1,
1500  *p2;
1501 
1502  /* Sort trigrams to ease duplicate detection */
1503  qsort(colorTrgms, arcsCount, sizeof(ColorTrgmInfo), colorTrgmInfoCmp);
1504 
1505  /* p1 is probe point, p2 is last known non-duplicate. */
1506  p2 = colorTrgms;
1507  for (p1 = colorTrgms + 1; p1 < colorTrgms + arcsCount; p1++)
1508  {
1509  if (colorTrgmInfoCmp(p1, p2) > 0)
1510  {
1511  p2++;
1512  *p2 = *p1;
1513  }
1514  else
1515  {
1516  p2->arcs = list_concat(p2->arcs, p1->arcs);
1517  }
1518  }
1519  trgmNFA->colorTrgmsCount = (p2 - colorTrgms) + 1;
1520  }
1521  else
1522  {
1523  trgmNFA->colorTrgmsCount = arcsCount;
1524  }
1525 
1526  /*
1527  * Count number of simple trigrams generated by each color trigram, and
1528  * also compute a penalty value, which is the number of simple trigrams
1529  * times a multiplier that depends on its whitespace content.
1530  *
1531  * Note: per-color-trigram counts cannot overflow an int so long as
1532  * COLOR_COUNT_LIMIT is not more than the cube root of INT_MAX, ie about
1533  * 1290. However, the grand total totalTrgmCount might conceivably
1534  * overflow an int, so we use int64 for that within this routine. Also,
1535  * penalties are calculated in float4 arithmetic to avoid any overflow
1536  * worries.
1537  */
1538  totalTrgmCount = 0;
1539  totalTrgmPenalty = 0.0f;
1540  for (i = 0; i < trgmNFA->colorTrgmsCount; i++)
1541  {
1542  ColorTrgmInfo *trgmInfo = &colorTrgms[i];
1543  int j,
1544  count = 1,
1545  typeIndex = 0;
1546 
1547  for (j = 0; j < 3; j++)
1548  {
1549  TrgmColor c = trgmInfo->ctrgm.colors[j];
1550 
1551  typeIndex *= 2;
1552  if (c == COLOR_BLANK)
1553  typeIndex++;
1554  else
1555  count *= trgmNFA->colorInfo[c].wordCharsCount;
1556  }
1557  trgmInfo->count = count;
1558  totalTrgmCount += count;
1559  trgmInfo->penalty = penalties[typeIndex] * (float4) count;
1560  totalTrgmPenalty += trgmInfo->penalty;
1561  }
1562 
1563  /* Sort color trigrams in descending order of their penalties */
1564  qsort(colorTrgms, trgmNFA->colorTrgmsCount, sizeof(ColorTrgmInfo),
1566 
1567  /*
1568  * Remove color trigrams from the graph so long as total penalty of color
1569  * trigrams exceeds WISH_TRGM_PENALTY. (If we fail to get down to
1570  * WISH_TRGM_PENALTY, it's OK so long as total count is no more than
1571  * MAX_TRGM_COUNT.) We prefer to remove color trigrams with higher
1572  * penalty, since those are the most promising for reducing the total
1573  * penalty. When removing a color trigram we have to merge states
1574  * connected by arcs labeled with that trigram. It's necessary to not
1575  * merge initial and final states, because our graph becomes useless if
1576  * that happens; so we cannot always remove the trigram we'd prefer to.
1577  */
1578  for (i = 0; i < trgmNFA->colorTrgmsCount; i++)
1579  {
1580  ColorTrgmInfo *trgmInfo = &colorTrgms[i];
1581  bool canRemove = true;
1582  ListCell *cell;
1583 
1584  /* Done if we've reached the target */
1585  if (totalTrgmPenalty <= WISH_TRGM_PENALTY)
1586  break;
1587 
1588 #ifdef TRGM_REGEXP_DEBUG
1589  fprintf(stderr, "considering ctrgm %d %d %d, penalty %f, %d arcs\n",
1590  trgmInfo->ctrgm.colors[0],
1591  trgmInfo->ctrgm.colors[1],
1592  trgmInfo->ctrgm.colors[2],
1593  trgmInfo->penalty,
1594  list_length(trgmInfo->arcs));
1595 #endif
1596 
1597  /*
1598  * Does any arc of this color trigram connect initial and final
1599  * states? If so we can't remove it.
1600  */
1601  foreach(cell, trgmInfo->arcs)
1602  {
1603  TrgmArcInfo *arcInfo = (TrgmArcInfo *) lfirst(cell);
1604  TrgmState *source = arcInfo->source,
1605  *target = arcInfo->target;
1606  int source_flags,
1607  target_flags;
1608 
1609 #ifdef TRGM_REGEXP_DEBUG
1610  fprintf(stderr, "examining arc to s%d (%x) from s%d (%x)\n",
1611  -target->snumber, target->flags,
1612  -source->snumber, source->flags);
1613 #endif
1614 
1615  /* examine parent states, if any merging has already happened */
1616  while (source->parent)
1617  source = source->parent;
1618  while (target->parent)
1619  target = target->parent;
1620 
1621 #ifdef TRGM_REGEXP_DEBUG
1622  fprintf(stderr, " ... after completed merges: to s%d (%x) from s%d (%x)\n",
1623  -target->snumber, target->flags,
1624  -source->snumber, source->flags);
1625 #endif
1626 
1627  /* we must also consider merges we are planning right now */
1628  source_flags = source->flags | source->tentFlags;
1629  while (source->tentParent)
1630  {
1631  source = source->tentParent;
1632  source_flags |= source->flags | source->tentFlags;
1633  }
1634  target_flags = target->flags | target->tentFlags;
1635  while (target->tentParent)
1636  {
1637  target = target->tentParent;
1638  target_flags |= target->flags | target->tentFlags;
1639  }
1640 
1641 #ifdef TRGM_REGEXP_DEBUG
1642  fprintf(stderr, " ... after tentative merges: to s%d (%x) from s%d (%x)\n",
1643  -target->snumber, target_flags,
1644  -source->snumber, source_flags);
1645 #endif
1646 
1647  /* would fully-merged state have both INIT and FIN set? */
1648  if (((source_flags | target_flags) & (TSTATE_INIT | TSTATE_FIN)) ==
1649  (TSTATE_INIT | TSTATE_FIN))
1650  {
1651  canRemove = false;
1652  break;
1653  }
1654 
1655  /* ok so far, so remember planned merge */
1656  if (source != target)
1657  {
1658 #ifdef TRGM_REGEXP_DEBUG
1659  fprintf(stderr, " ... tentatively merging s%d into s%d\n",
1660  -target->snumber, -source->snumber);
1661 #endif
1662  target->tentParent = source;
1663  source->tentFlags |= target_flags;
1664  }
1665  }
1666 
1667  /*
1668  * We must reset all the tentFlags/tentParent fields before
1669  * continuing. tentFlags could only have become set in states that
1670  * are the source or parent or tentative parent of one of the current
1671  * arcs; likewise tentParent could only have become set in states that
1672  * are the target or parent or tentative parent of one of the current
1673  * arcs. There might be some overlap between those sets, but if we
1674  * clear tentFlags in target states as well as source states, we
1675  * should be okay even if we visit a state as target before visiting
1676  * it as a source.
1677  */
1678  foreach(cell, trgmInfo->arcs)
1679  {
1680  TrgmArcInfo *arcInfo = (TrgmArcInfo *) lfirst(cell);
1681  TrgmState *source = arcInfo->source,
1682  *target = arcInfo->target;
1683  TrgmState *ttarget;
1684 
1685  /* no need to touch previously-merged states */
1686  while (source->parent)
1687  source = source->parent;
1688  while (target->parent)
1689  target = target->parent;
1690 
1691  while (source)
1692  {
1693  source->tentFlags = 0;
1694  source = source->tentParent;
1695  }
1696 
1697  while ((ttarget = target->tentParent) != NULL)
1698  {
1699  target->tentParent = NULL;
1700  target->tentFlags = 0; /* in case it was also a source */
1701  target = ttarget;
1702  }
1703  }
1704 
1705  /* Now, move on if we can't drop this trigram */
1706  if (!canRemove)
1707  {
1708 #ifdef TRGM_REGEXP_DEBUG
1709  fprintf(stderr, " ... not ok to merge\n");
1710 #endif
1711  continue;
1712  }
1713 
1714  /* OK, merge states linked by each arc labeled by the trigram */
1715  foreach(cell, trgmInfo->arcs)
1716  {
1717  TrgmArcInfo *arcInfo = (TrgmArcInfo *) lfirst(cell);
1718  TrgmState *source = arcInfo->source,
1719  *target = arcInfo->target;
1720 
1721  while (source->parent)
1722  source = source->parent;
1723  while (target->parent)
1724  target = target->parent;
1725  if (source != target)
1726  {
1727 #ifdef TRGM_REGEXP_DEBUG
1728  fprintf(stderr, "merging s%d into s%d\n",
1729  -target->snumber, -source->snumber);
1730 #endif
1731  mergeStates(source, target);
1732  /* Assert we didn't merge initial and final states */
1733  Assert((source->flags & (TSTATE_INIT | TSTATE_FIN)) !=
1734  (TSTATE_INIT | TSTATE_FIN));
1735  }
1736  }
1737 
1738  /* Mark trigram unexpanded, and update totals */
1739  trgmInfo->expanded = false;
1740  totalTrgmCount -= trgmInfo->count;
1741  totalTrgmPenalty -= trgmInfo->penalty;
1742  }
1743 
1744  /* Did we succeed in fitting into MAX_TRGM_COUNT? */
1745  if (totalTrgmCount > MAX_TRGM_COUNT)
1746  return false;
1747 
1748  trgmNFA->totalTrgmCount = (int) totalTrgmCount;
1749 
1750  /*
1751  * Sort color trigrams by colors (will be useful for bsearch in packGraph)
1752  * and enumerate the color trigrams that are expanded.
1753  */
1754  cnumber = 0;
1755  qsort(colorTrgms, trgmNFA->colorTrgmsCount, sizeof(ColorTrgmInfo),
1757  for (i = 0; i < trgmNFA->colorTrgmsCount; i++)
1758  {
1759  if (colorTrgms[i].expanded)
1760  {
1761  colorTrgms[i].cnumber = cnumber;
1762  cnumber++;
1763  }
1764  }
1765 
1766  return true;
1767 }
static void mergeStates(TrgmState *state1, TrgmState *state2)
Definition: trgm_regexp.c:1876
ColorTrgm ctrgm
Definition: trgm_regexp.c:348
struct TrgmState * tentParent
Definition: trgm_regexp.c:340
TrgmColorInfo * colorInfo
Definition: trgm_regexp.c:403
float4 penalty
Definition: trgm_regexp.c:377
Definition: regguts.h:290
TrgmColor colors[3]
Definition: trgm_regexp.c:299
HTAB * states
Definition: trgm_regexp.c:407
#define WISH_TRGM_PENALTY
Definition: trgm_regexp.c:221
List * list_concat(List *list1, const List *list2)
Definition: list.c:530
#define TSTATE_FIN
Definition: trgm_regexp.c:329
#define TSTATE_INIT
Definition: trgm_regexp.c:328
int totalTrgmCount
Definition: trgm_regexp.c:420
#define fprintf
Definition: port.h:220
#define list_make1(x1)
Definition: pg_list.h:206
char * c
TrgmState * target
Definition: trgm_regexp.c:360
ColorTrgmInfo * colorTrgms
Definition: trgm_regexp.c:418
TrgmState * target
Definition: trgm_regexp.c:349
List * arcs
Definition: trgm_regexp.c:334
TrgmState * source
Definition: trgm_regexp.c:359
int arcsCount
Definition: trgm_regexp.c:414
#define COLOR_BLANK
Definition: trgm_regexp.c:286
float float4
Definition: c.h:564
void * palloc0(Size size)
Definition: mcxt.c:1093
static int colorTrgmInfoPenaltyCmp(const void *p1, const void *p2)
Definition: trgm_regexp.c:1906
int colorTrgmsCount
Definition: trgm_regexp.c:419
#define MAX_TRGM_COUNT
Definition: trgm_regexp.c:220
int tentFlags
Definition: trgm_regexp.c:339
#define Assert(condition)
Definition: c.h:804
#define lfirst(lc)
Definition: pg_list.h:169
Definition: regguts.h:317
static rewind_source * source
Definition: pg_rewind.c:79
static int list_length(const List *l)
Definition: pg_list.h:149
void * hash_seq_search(HASH_SEQ_STATUS *status)
Definition: dynahash.c:1436
void hash_seq_init(HASH_SEQ_STATUS *status, HTAB *hashp)
Definition: dynahash.c:1426
static const float4 penalties[8]
Definition: trgm_regexp.c:228
static int colorTrgmInfoCmp(const void *p1, const void *p2)
Definition: trgm_regexp.c:1893
struct TrgmState * parent
Definition: trgm_regexp.c:338
void * palloc(Size size)
Definition: mcxt.c:1062
int i
ColorTrgm ctrgm
Definition: trgm_regexp.c:374
#define qsort(a, b, c, d)
Definition: port.h:504
int TrgmColor
Definition: trgm_regexp.c:282

◆ transformGraph()

static void transformGraph ( TrgmNFA trgmNFA)
static

Definition at line 903 of file trgm_regexp.c.

References TrgmNFA::arcsCount, COLOR_UNKNOWN, TrgmPrefix::colors, CurrentMemoryContext, HASHCTL::entrysize, TrgmState::flags, getState(), HASH_BLOBS, HASH_CONTEXT, hash_create(), HASH_ELEM, hash_get_num_entries(), HASHCTL::hcxt, TrgmNFA::initState, HASHCTL::keysize, TrgmNFA::keysQueue, linitial, list_delete_first(), MAX_EXPANDED_ARCS, MAX_EXPANDED_STATES, MemSet, NIL, TrgmStateKey::nstate, TrgmNFA::nstates, TrgmNFA::overflowed, pg_reg_getinitialstate(), TrgmStateKey::prefix, processState(), TrgmNFA::queue, TrgmNFA::regex, TrgmNFA::states, TSTATE_FIN, and TSTATE_INIT.

Referenced by createTrgmNFAInternal().

904 {
905  HASHCTL hashCtl;
906  TrgmStateKey initkey;
907  TrgmState *initstate;
908 
909  /* Initialize this stage's workspace in trgmNFA struct */
910  trgmNFA->queue = NIL;
911  trgmNFA->keysQueue = NIL;
912  trgmNFA->arcsCount = 0;
913  trgmNFA->overflowed = false;
914 
915  /* Create hashtable for states */
916  hashCtl.keysize = sizeof(TrgmStateKey);
917  hashCtl.entrysize = sizeof(TrgmState);
918  hashCtl.hcxt = CurrentMemoryContext;
919  trgmNFA->states = hash_create("Trigram NFA",
920  1024,
921  &hashCtl,
923  trgmNFA->nstates = 0;
924 
925  /* Create initial state: ambiguous prefix, NFA's initial state */
926  MemSet(&initkey, 0, sizeof(initkey));
927  initkey.prefix.colors[0] = COLOR_UNKNOWN;
928  initkey.prefix.colors[1] = COLOR_UNKNOWN;
929  initkey.nstate = pg_reg_getinitialstate(trgmNFA->regex);
930 
931  initstate = getState(trgmNFA, &initkey);
932  initstate->flags |= TSTATE_INIT;
933  trgmNFA->initState = initstate;
934 
935  /*
936  * Recursively build the expanded graph by processing queue of states
937  * (breadth-first search). getState already put initstate in the queue.
938  */
939  while (trgmNFA->queue != NIL)
940  {
941  TrgmState *state = (TrgmState *) linitial(trgmNFA->queue);
942 
943  trgmNFA->queue = list_delete_first(trgmNFA->queue);
944 
945  /*
946  * If we overflowed then just mark state as final. Otherwise do
947  * actual processing.
948  */
949  if (trgmNFA->overflowed)
950  state->flags |= TSTATE_FIN;
951  else
952  processState(trgmNFA, state);
953 
954  /* Did we overflow? */
955  if (trgmNFA->arcsCount > MAX_EXPANDED_ARCS ||
957  trgmNFA->overflowed = true;
958  }
959 }
#define MAX_EXPANDED_ARCS
Definition: trgm_regexp.c:219
#define NIL
Definition: pg_list.h:65
struct TrgmState TrgmState
#define HASH_CONTEXT
Definition: hsearch.h:102
#define HASH_ELEM
Definition: hsearch.h:95
MemoryContext hcxt
Definition: hsearch.h:86
regex_t * regex
Definition: trgm_regexp.c:402
HTAB * states
Definition: trgm_regexp.c:407
Size entrysize
Definition: hsearch.h:76
#define MemSet(start, val, len)
Definition: c.h:1008
long hash_get_num_entries(HTAB *hashp)
Definition: dynahash.c:1382
TrgmState * initState
Definition: trgm_regexp.c:408
#define TSTATE_FIN
Definition: trgm_regexp.c:329
#define TSTATE_INIT
Definition: trgm_regexp.c:328
bool overflowed
Definition: trgm_regexp.c:415
int nstates
Definition: trgm_regexp.c:409
#define linitial(l)
Definition: pg_list.h:174
TrgmColor colors[2]
Definition: trgm_regexp.c:290
int pg_reg_getinitialstate(const regex_t *regex)
Definition: regexport.c:50
HTAB * hash_create(const char *tabname, long nelem, const HASHCTL *info, int flags)
Definition: dynahash.c:349
MemoryContext CurrentMemoryContext
Definition: mcxt.c:42
int arcsCount
Definition: trgm_regexp.c:414
List * queue
Definition: trgm_regexp.c:412
#define HASH_BLOBS
Definition: hsearch.h:97
Size keysize
Definition: hsearch.h:75
Definition: regguts.h:317
static TrgmState * getState(TrgmNFA *trgmNFA, TrgmStateKey *key)
Definition: trgm_regexp.c:1384
TrgmPrefix prefix
Definition: trgm_regexp.c:309
#define MAX_EXPANDED_STATES
Definition: trgm_regexp.c:218
#define COLOR_UNKNOWN
Definition: trgm_regexp.c:285
List * keysQueue
Definition: trgm_regexp.c:413
static void processState(TrgmNFA *trgmNFA, TrgmState *state)
Definition: trgm_regexp.c:965
List * list_delete_first(List *list)
Definition: list.c:875

◆ trigramsMatchGraph()

bool trigramsMatchGraph ( TrgmPackedGraph graph,
bool check 
)

Definition at line 636 of file trgm_regexp.c.

References TrgmPackedState::arcs, TrgmPackedState::arcsCount, TrgmPackedArc::colorTrgm, TrgmPackedGraph::colorTrigramGroups, TrgmPackedGraph::colorTrigramsActive, TrgmPackedGraph::colorTrigramsCount, i, TrgmPackedGraph::states, TrgmPackedGraph::statesActive, TrgmPackedGraph::statesCount, TrgmPackedGraph::statesQueue, and TrgmPackedArc::targetState.

Referenced by gin_trgm_consistent(), gin_trgm_triconsistent(), and gtrgm_consistent().

637 {
638  int i,
639  j,
640  k,
641  queueIn,
642  queueOut;
643 
644  /*
645  * Reset temporary working areas.
646  */
647  memset(graph->colorTrigramsActive, 0,
648  sizeof(bool) * graph->colorTrigramsCount);
649  memset(graph->statesActive, 0, sizeof(bool) * graph->statesCount);
650 
651  /*
652  * Check which color trigrams were matched. A match for any simple
653  * trigram associated with a color trigram counts as a match of the color
654  * trigram.
655  */
656  j = 0;
657  for (i = 0; i < graph->colorTrigramsCount; i++)
658  {
659  int cnt = graph->colorTrigramGroups[i];
660 
661  for (k = j; k < j + cnt; k++)
662  {
663  if (check[k])
664  {
665  /*
666  * Found one matched trigram in the group. Can skip the rest
667  * of them and go to the next group.
668  */
669  graph->colorTrigramsActive[i] = true;
670  break;
671  }
672  }
673  j = j + cnt;
674  }
675 
676  /*
677  * Initialize the statesQueue to hold just the initial state. Note:
678  * statesQueue has room for statesCount entries, which is certainly enough
679  * since no state will be put in the queue more than once. The
680  * statesActive array marks which states have been queued.
681  */
682  graph->statesActive[0] = true;
683  graph->statesQueue[0] = 0;
684  queueIn = 0;
685  queueOut = 1;
686 
687  /* Process queued states as long as there are any. */
688  while (queueIn < queueOut)
689  {
690  int stateno = graph->statesQueue[queueIn++];
691  TrgmPackedState *state = &graph->states[stateno];
692  int cnt = state->arcsCount;
693 
694  /* Loop over state's out-arcs */
695  for (i = 0; i < cnt; i++)
696  {
697  TrgmPackedArc *arc = &state->arcs[i];
698 
699  /*
700  * If corresponding color trigram is present then activate the
701  * corresponding state. We're done if that's the final state,
702  * otherwise queue the state if it's not been queued already.
703  */
704  if (graph->colorTrigramsActive[arc->colorTrgm])
705  {
706  int nextstate = arc->targetState;
707 
708  if (nextstate == 1)
709  return true; /* success: final state is reachable */
710 
711  if (!graph->statesActive[nextstate])
712  {
713  graph->statesActive[nextstate] = true;
714  graph->statesQueue[queueOut++] = nextstate;
715  }
716  }
717  }
718  }
719 
720  /* Queue is empty, so match fails. */
721  return false;
722 }
bool * colorTrigramsActive
Definition: trgm_regexp.c:461
Definition: regguts.h:290
TrgmPackedState * states
Definition: trgm_regexp.c:458
TrgmPackedArc * arcs
Definition: trgm_regexp.c:435
bool * statesActive
Definition: trgm_regexp.c:462
Definition: regguts.h:317
int i
int * colorTrigramGroups
Definition: trgm_regexp.c:451

◆ validArcLabel()

static bool validArcLabel ( TrgmStateKey key,
TrgmColor  co 
)
static

Definition at line 1329 of file trgm_regexp.c.

References Assert, COLOR_BLANK, COLOR_UNKNOWN, TrgmPrefix::colors, and TrgmStateKey::prefix.

Referenced by addArc(), and addKey().

1330 {
1331  /*
1332  * We have to know full trigram in order to add outgoing arc. So we can't
1333  * do it if prefix is ambiguous.
1334  */
1335  if (key->prefix.colors[0] == COLOR_UNKNOWN)
1336  return false;
1337 
1338  /* If key->prefix.colors[0] isn't unknown, its second color isn't either */
1339  Assert(key->prefix.colors[1] != COLOR_UNKNOWN);
1340  /* And we should not be called with an unknown arc color anytime */
1341  Assert(co != COLOR_UNKNOWN);
1342 
1343  /*
1344  * We don't bother with making arcs representing three non-word
1345  * characters, since that's useless for trigram extraction.
1346  */
1347  if (key->prefix.colors[0] == COLOR_BLANK &&
1348  key->prefix.colors[1] == COLOR_BLANK &&
1349  co == COLOR_BLANK)
1350  return false;
1351 
1352  /*
1353  * We also reject nonblank-blank-anything. The nonblank-blank-nonblank
1354  * case doesn't correspond to any trigram the trigram extraction code
1355  * would make. The nonblank-blank-blank case is also not possible with
1356  * RPADDING = 1. (Note that in many cases we'd fail to generate such a
1357  * trigram even if it were valid, for example processing "foo bar" will
1358  * not result in considering the trigram "o ". So if you want to support
1359  * RPADDING = 2, there's more to do than just twiddle this test.)
1360  */
1361  if (key->prefix.colors[0] != COLOR_BLANK &&
1362  key->prefix.colors[1] == COLOR_BLANK)
1363  return false;
1364 
1365  /*
1366  * Other combinations involving blank are valid, in particular we assume
1367  * blank-blank-nonblank is valid, which presumes that LPADDING is 2.
1368  *
1369  * Note: Using again the example "foo bar", we will not consider the
1370  * trigram " b", though this trigram would be found by the trigram
1371  * extraction code. Since we will find " ba", it doesn't seem worth
1372  * trying to hack the algorithm to generate the additional trigram.
1373  */
1374 
1375  /* arc label is valid */
1376  return true;
1377 }
TrgmColor colors[2]
Definition: trgm_regexp.c:290
#define COLOR_BLANK
Definition: trgm_regexp.c:286
#define Assert(condition)
Definition: c.h:804
TrgmPrefix prefix
Definition: trgm_regexp.c:309
#define COLOR_UNKNOWN
Definition: trgm_regexp.c:285

Variable Documentation

◆ penalties

const float4 penalties[8]
static
Initial value:
= {
1.0f,
3.5f,
0.0f,
0.0f,
4.2f,
2.1f,
25.0f,
0.0f
}

Definition at line 228 of file trgm_regexp.c.

Referenced by selectColorTrigrams().