From: dan <dan@noemail.net>
Date: Wed, 18 Nov 2009 15:35:58 +0000 (+0000)
Subject: Add some missing comments and fix some other issues in fts3 code.
X-Git-Tag: fts3-refactor~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=bd61689382ef31c9a4a3a337c939814814bb1784;p=thirdparty%2Fsqlite.git

Add some missing comments and fix some other issues in fts3 code.

FossilOrigin-Name: 2fe579e778b75fbf503c02e01e5424c1926f2b49
---

diff --git a/ext/fts3/fts3.c b/ext/fts3/fts3.c
index 08d4311163..137f1e446d 100644
--- a/ext/fts3/fts3.c
+++ b/ext/fts3/fts3.c
@@ -895,38 +895,6 @@ static int fts3NextMethod(sqlite3_vtab_cursor *pCursor){
 }
 
 
-/* TODO(shess) If we pushed LeafReader to the top of the file, or to
-** another file, term_select() could be pushed above
-** docListOfTerm().
-*/
-/*
-** Read a single block from the %_segments table.
-*/
-static int fts3ReadBlock(
-  Fts3Table *p,
-  sqlite3_int64 iBlock,
-  char const **pzBlock,
-  int *pnBlock
-){
-  sqlite3_stmt *pStmt;
-  int rc = sqlite3Fts3SqlStmt(p, FTS3_SQL_GET_BLOCK, &pStmt);
-  if( rc!=SQLITE_OK ) return rc;
-  sqlite3_reset(pStmt);
-
-  sqlite3_bind_int64(pStmt, 1, iBlock);
-  rc = sqlite3_step(pStmt); 
-  if( rc!=SQLITE_ROW ){
-    return SQLITE_CORRUPT;
-  }
-
-  *pnBlock = sqlite3_column_bytes(pStmt, 0);
-  *pzBlock = (char *)sqlite3_column_blob(pStmt, 0);
-  if( !*pzBlock ){
-    return SQLITE_NOMEM;
-  }
-  return SQLITE_OK;
-}
-
 /*
 ** The buffer pointed to by argument zNode (size nNode bytes) contains the
 ** root node of a b-tree segment. The segment is guaranteed to be at least
@@ -1013,7 +981,7 @@ static int fts3SelectLeaf(
     }
 
     /* Descend to interior node iChild. */
-    rc = fts3ReadBlock(p, iChild, &zCsr, &nBlock);
+    rc = sqlite3Fts3ReadBlock(p, iChild, &zCsr, &nBlock);
     if( rc!=SQLITE_OK ) break;
     zEnd = &zCsr[nBlock];
   }
@@ -1524,7 +1492,7 @@ static int fts3TermSelect(
   ** (unless the root node happens to be a leaf). It simply examines the
   ** b-tree structure to determine which leaves need to be inspected.
   */
-  rc = sqlite3Fts3SqlStmt(p, FTS3_SQL_GET_ALL_SEGDIRS, &pStmt);
+  rc = sqlite3Fts3AllSegdirs(p, &pStmt);
   while( rc==SQLITE_OK && SQLITE_ROW==(rc = sqlite3_step(pStmt)) ){
     Fts3SegReader *pNew = 0;
     int nRoot = sqlite3_column_bytes(pStmt, 4);
diff --git a/ext/fts3/fts3Int.h b/ext/fts3/fts3Int.h
index 4c66825642..af80792a1b 100644
--- a/ext/fts3/fts3Int.h
+++ b/ext/fts3/fts3Int.h
@@ -174,6 +174,15 @@ int sqlite3Fts3UpdateMethod(sqlite3_vtab*,int,sqlite3_value**,sqlite3_int64*);
 int sqlite3Fts3PendingTermsFlush(Fts3Table *);
 void sqlite3Fts3PendingTermsClear(Fts3Table *);
 int sqlite3Fts3Optimize(Fts3Table *);
+int sqlite3Fts3SegReaderNew(Fts3Table *,int, sqlite3_int64,
+  sqlite3_int64, sqlite3_int64, const char *, int, Fts3SegReader**);
+void sqlite3Fts3SegReaderFree(Fts3SegReader *);
+int sqlite3Fts3SegReaderIterate(
+  Fts3Table *, Fts3SegReader **, int, Fts3SegFilter *,
+  int (*)(Fts3Table *, void *, char *, int, char *, int),  void *
+);
+int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char const**, int*);
+int sqlite3Fts3AllSegdirs(Fts3Table*, sqlite3_stmt **);
 
 /* Flags allowed as part of the 4th argument to SegmentReaderIterate() */
 #define FTS3_SEGMENT_REQUIRE_POS   0x00000001
@@ -181,6 +190,7 @@ int sqlite3Fts3Optimize(Fts3Table *);
 #define FTS3_SEGMENT_COLUMN_FILTER 0x00000004
 #define FTS3_SEGMENT_PREFIX        0x00000008
 
+/* Type passed as 4th argument to SegmentReaderIterate() */
 struct Fts3SegFilter {
   const char *zTerm;
   int nTerm;
@@ -188,15 +198,6 @@ struct Fts3SegFilter {
   int flags;
 };
 
-int sqlite3Fts3SegReaderNew(Fts3Table *,int, sqlite3_int64,
-  sqlite3_int64, sqlite3_int64, const char *, int, Fts3SegReader**);
-void sqlite3Fts3SegReaderFree(Fts3SegReader *);
-
-int sqlite3Fts3SegReaderIterate(
-  Fts3Table *, Fts3SegReader **, int, Fts3SegFilter *,
-  int (*)(Fts3Table *, void *, char *, int, char *, int),  void *
-);
-
 /* fts3.c */
 int sqlite3Fts3PutVarint(char *, sqlite3_int64);
 int sqlite3Fts3GetVarint(const char *, sqlite_int64 *);
@@ -204,11 +205,6 @@ int sqlite3Fts3GetVarint32(const char *, int *);
 int sqlite3Fts3VarintLen(sqlite3_uint64);
 void sqlite3Fts3Dequote(char *);
 
-/* Valid arguments for the second argument to sqlite3Fts3SqlStmt() */
-#define FTS3_SQL_GET_ALL_SEGDIRS 11
-#define FTS3_SQL_GET_BLOCK 17
-int sqlite3Fts3SqlStmt(Fts3Table *, int, sqlite3_stmt **);
-
 /* fts3_tokenizer.c */
 const char *sqlite3Fts3NextToken(const char *, int *);
 int sqlite3Fts3InitHashTable(sqlite3 *, Fts3Hash *, const char *);
diff --git a/ext/fts3/fts3_write.c b/ext/fts3/fts3_write.c
index f4b8a9b2ec..b65e05f2d4 100644
--- a/ext/fts3/fts3_write.c
+++ b/ext/fts3/fts3_write.c
@@ -29,6 +29,11 @@ typedef struct PendingList PendingList;
 typedef struct SegmentNode SegmentNode;
 typedef struct SegmentWriter SegmentWriter;
 
+/*
+** Data structure used while accumulating terms in the pending-terms hash
+** table. The hash table entry maps from term (a string) to a malloced
+** instance of this structure.
+*/
 struct PendingList {
   int nData;
   char *aData;
@@ -39,9 +44,15 @@ struct PendingList {
 };
 
 /*
-** fts3SegReaderNew()
-** fts3SegReaderNext()
-** sqlite3Fts3SegReaderFree()
+** An instance of this structure is used to iterate through the terms on
+** a contiguous set of segment b-tree leaf nodes. Although the details of
+** this structure are only manipulated by code in this file, opaque handles
+** of type Fts3SegReader* are also used by code in fts3.c to iterate through
+** terms when querying the full-text index. See functions:
+**
+**   sqlite3Fts3SegReaderNew()
+**   sqlite3Fts3SegReaderFree()
+**   sqlite3Fts3SegReaderIterate()
 */
 struct Fts3SegReader {
   int iIdx;                       /* Index within level */
@@ -68,9 +79,13 @@ struct Fts3SegReader {
 };
 
 /*
-** fts3LeafAdd()
-** fts3LeafWrite()
-** fts3LeafFree()
+** An instance of this structure is used to create a segment b-tree in the
+** database. The internal details of this type are only accessed by the
+** following functions:
+**
+**   fts3SegWriterAdd()
+**   fts3SegWriterFlush()
+**   fts3SegWriterFree()
 */
 struct SegmentWriter {
   SegmentNode *pTree;             /* Pointer to interior tree structure */
@@ -88,8 +103,8 @@ struct SegmentWriter {
 /*
 ** Type SegmentNode is used by the following three functions to create
 ** the interior part of the segment b+-tree structures (everything except
-** the leaf nodes. These functions and type are only ever used by code
-** within the fts3LeafXXX() family of functions described above.
+** the leaf nodes). These functions and type are only ever used by code
+** within the fts3SegWriterXXX() family of functions described above.
 **
 **   fts3NodeAddTerm()
 **   fts3NodeWrite()
@@ -109,23 +124,8 @@ struct SegmentNode {
 };
 
 /*
-** This is a comparison function used as a qsort() callback when sorting
-** an array of pending terms by term.
+** Valid values for the second argument to fts3SqlStmt().
 */
-static int qsortCompare(const void *lhs, const void *rhs){
-  char *z1 = fts3HashKey(*(Fts3HashElem **)lhs);
-  char *z2 = fts3HashKey(*(Fts3HashElem **)rhs);
-  int n1 = fts3HashKeysize(*(Fts3HashElem **)lhs);
-  int n2 = fts3HashKeysize(*(Fts3HashElem **)rhs);
-
-  int n = (n1<n2 ? n1 : n2);
-  int c = memcmp(z1, z2, n);
-  if( c==0 ){
-    c = n1 - n2;
-  }
-  return c;
-}
-
 #define SQL_DELETE_CONTENT             0
 #define SQL_IS_EMPTY                   1
 #define SQL_DELETE_ALL_CONTENT         2 
@@ -136,15 +136,14 @@ static int qsortCompare(const void *lhs, const void *rhs){
 #define SQL_INSERT_SEGMENTS            7
 #define SQL_NEXT_SEGMENTS_ID           8
 #define SQL_INSERT_SEGDIR              9
-
 #define SQL_SELECT_LEVEL              10
 #define SQL_SELECT_ALL_LEVEL          11
 #define SQL_SELECT_LEVEL_COUNT        12
 #define SQL_SELECT_SEGDIR_COUNT_MAX   13
-
 #define SQL_DELETE_SEGDIR_BY_LEVEL    14
 #define SQL_DELETE_SEGMENTS_RANGE     15
 #define SQL_CONTENT_INSERT            16
+#define SQL_GET_BLOCK                 17
 
 static int fts3SqlStmt(
   Fts3Table *p, 
@@ -207,10 +206,57 @@ static int fts3SqlStmt(
   return rc;
 }
 
-int sqlite3Fts3SqlStmt(Fts3Table *p, int eStmt, sqlite3_stmt **ppStmt){
-  return fts3SqlStmt(p, eStmt, ppStmt, 0);
+/*
+** Read a single block from the %_segments table. If the specified block
+** does not exist, return SQLITE_CORRUPT. If some other error (malloc, IO 
+** etc.) occurs, return the appropriate SQLite error code.
+**
+** Otherwise, if successful, set *pzBlock to point to a buffer containing
+** the block read from the database, and *pnBlock to the size of the read
+** block in bytes.
+**
+** WARNING: The returned buffer is only valid until the next call to 
+** sqlite3Fts3ReadBlock().
+*/
+int sqlite3Fts3ReadBlock(
+  Fts3Table *p,
+  sqlite3_int64 iBlock,
+  char const **pzBlock,
+  int *pnBlock
+){
+  sqlite3_stmt *pStmt;
+  int rc = fts3SqlStmt(p, SQL_GET_BLOCK, &pStmt, 0);
+  if( rc!=SQLITE_OK ) return rc;
+  sqlite3_reset(pStmt);
+
+  sqlite3_bind_int64(pStmt, 1, iBlock);
+  rc = sqlite3_step(pStmt); 
+  if( rc!=SQLITE_ROW ){
+    return SQLITE_CORRUPT;
+  }
+
+  *pnBlock = sqlite3_column_bytes(pStmt, 0);
+  *pzBlock = (char *)sqlite3_column_blob(pStmt, 0);
+  if( !*pzBlock ){
+    return SQLITE_NOMEM;
+  }
+  return SQLITE_OK;
 }
 
+/*
+** Set *ppStmt to a statement handle that may be used to iterate through
+** all rows in the %_segdir table, from oldest to newest. If successful,
+** return SQLITE_OK. If an error occurs while preparing the statement, 
+** return an SQLite error code.
+**
+** There is only ever one instance of this SQL statement compiled for
+** each FTS3 table.
+*/
+int sqlite3Fts3AllSegdirs(Fts3Table *p, sqlite3_stmt **ppStmt){
+  return fts3SqlStmt(p, SQL_SELECT_ALL_LEVEL, ppStmt, 0);
+}
+
+
 static int fts3SqlExec(Fts3Table *p, int eStmt, sqlite3_value **apVal){
   sqlite3_stmt *pStmt;
   int rc = fts3SqlStmt(p, eStmt, &pStmt, apVal); 
@@ -1191,7 +1237,7 @@ static void fts3NodeFree(SegmentNode *pTree){
   }
 }
 
-static int fts3LeafAdd(
+static int fts3SegWriterAdd(
   Fts3Table *p,                   /* Virtual table handle */
   SegmentWriter **ppWriter,       /* IN/OUT: SegmentWriter handle */ 
   int isCopyTerm,                 /* True if buffer zTerm must be copied */
@@ -1323,7 +1369,7 @@ static int fts3LeafAdd(
   return SQLITE_OK;
 }
 
-static int fts3LeafWrite(
+static int fts3SegWriterFlush(
   Fts3Table *p, 
   SegmentWriter *pWriter,
   int iLevel,
@@ -1352,7 +1398,7 @@ static int fts3LeafWrite(
   return rc;
 }
 
-static void fts3LeafFree(SegmentWriter *pWriter){
+static void fts3SegWriterFree(SegmentWriter *pWriter){
   if( pWriter ){
     sqlite3_free(pWriter->aData);
     sqlite3_free(pWriter->zMalloc);
@@ -1488,7 +1534,7 @@ static int fts3MergeCallback(
   int nDoclist
 ){
   SegmentWriter **ppW = (SegmentWriter **)pContext;
-  return fts3LeafAdd(p, ppW, 1, zTerm, nTerm, aDoclist, nDoclist);
+  return fts3SegWriterAdd(p, ppW, 1, zTerm, nTerm, aDoclist, nDoclist);
 }
 
 int sqlite3Fts3SegReaderIterate(
@@ -1517,7 +1563,7 @@ int sqlite3Fts3SegReaderIterate(
   */
   if( pFilter->zTerm ){
     int nTerm = pFilter->nTerm;
-    char *zTerm = pFilter->zTerm;
+    const char *zTerm = pFilter->zTerm;
     for(i=0; i<nSegment; i++){
       Fts3SegReader *pSeg = apSegment[i];
       while( fts3SegReaderTermCmp(pSeg, zTerm, nTerm)<0 ){
@@ -1726,11 +1772,11 @@ static int fts3SegmentMerge(Fts3Table *p, int iLevel){
 
   rc = fts3DeleteSegdir(p, iLevel, apSegment, nSegment);
   if( rc==SQLITE_OK ){
-    rc = fts3LeafWrite(p, pWriter, iNewLevel, iIdx);
+    rc = fts3SegWriterFlush(p, pWriter, iNewLevel, iIdx);
   }
 
  finished:
-  fts3LeafFree(pWriter);
+  fts3SegWriterFree(pWriter);
   if( apSegment ){
     for(i=0; i<nSegment; i++){
       sqlite3Fts3SegReaderFree(apSegment[i]);
@@ -1741,6 +1787,26 @@ static int fts3SegmentMerge(Fts3Table *p, int iLevel){
   return rc;
 }
 
+/*
+** This is a comparison function used as a qsort() callback when sorting
+** an array of pending terms by term. This occurs as part of flushing
+** the contents of the pending-terms hash table to the database.
+*/
+static int qsortCompare(const void *lhs, const void *rhs){
+  char *z1 = fts3HashKey(*(Fts3HashElem **)lhs);
+  char *z2 = fts3HashKey(*(Fts3HashElem **)rhs);
+  int n1 = fts3HashKeysize(*(Fts3HashElem **)lhs);
+  int n2 = fts3HashKeysize(*(Fts3HashElem **)rhs);
+
+  int n = (n1<n2 ? n1 : n2);
+  int c = memcmp(z1, z2, n);
+  if( c==0 ){
+    c = n1 - n2;
+  }
+  return c;
+}
+
+
 /* 
 ** Flush the contents of pendingTerms to a level 0 segment.
 */
@@ -1791,14 +1857,14 @@ int sqlite3Fts3PendingTermsFlush(Fts3Table *p){
     const char *z = fts3HashKey(apElem[i]);
     int n = fts3HashKeysize(apElem[i]);
     PendingList *pList = fts3HashData(apElem[i]);
-    rc = fts3LeafAdd(p, &pWriter, 0, z, n, pList->aData, pList->nData+1);
+    rc = fts3SegWriterAdd(p, &pWriter, 0, z, n, pList->aData, pList->nData+1);
   }
   if( rc==SQLITE_OK ){
-    rc = fts3LeafWrite(p, pWriter, 0, idx);
+    rc = fts3SegWriterFlush(p, pWriter, 0, idx);
   }
 
   /* Free all allocated resources before returning */
-  fts3LeafFree(pWriter);
+  fts3SegWriterFree(pWriter);
   sqlite3_free(apElem);
   sqlite3Fts3PendingTermsClear(p);
   return rc;
diff --git a/manifest b/manifest
index 07d603effa..fdc1a428da 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Improvements\sto\sthe\sway\sfts3\sreads\sthe\sfull-text\sindex.
-D 2009-11-17T12:52:10
+C Add\ssome\smissing\scomments\sand\sfix\ssome\sother\sissues\sin\sfts3\scode.
+D 2009-11-18T15:35:59
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 53f3dfa49f28ab5b80cb083fb7c9051e596bcfa1
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -56,9 +56,9 @@ F ext/fts2/mkfts2amal.tcl 974d5d438cb3f7c4a652639262f82418c1e4cff0
 F ext/fts3/README.syntax a19711dc5458c20734b8e485e75fb1981ec2427a
 F ext/fts3/README.tokenizers 998756696647400de63d5ba60e9655036cb966e9
 F ext/fts3/README.txt 8c18f41574404623b76917b9da66fcb0ab38328d
-F ext/fts3/fts3.c a72c19fa6270b5f88ad9b1215c821f7082164655
+F ext/fts3/fts3.c 2aa2c3f7b4d753f048af1c777b2c5fdd7e52c560
 F ext/fts3/fts3.h 3a10a0af180d502cecc50df77b1b22df142817fe
-F ext/fts3/fts3Int.h 5c040c0fb47ed81aaba589a55a7455c980592bea
+F ext/fts3/fts3Int.h f7488bbc9fd12bd3843f59265227321a92b39ed4
 F ext/fts3/fts3_expr.c bdf11f3602f62f36f0e42823680bf22033dae0de
 F ext/fts3/fts3_hash.c 1af1833a4d581ee8d668bb71f5a500f7a0104982
 F ext/fts3/fts3_hash.h 39524725425078bf9e814e9569c74a8e5a21b9fb
@@ -68,7 +68,7 @@ F ext/fts3/fts3_snippet.c 8ea9619247ac61c79aca650fc3307b8b4097b5f3
 F ext/fts3/fts3_tokenizer.c 185a212670a9bbdeb5cad6942305e681bce5c87b
 F ext/fts3/fts3_tokenizer.h 7ff73caa3327589bf6550f60d93ebdd1f6a0fb5c
 F ext/fts3/fts3_tokenizer1.c 0a5bcc579f35de5d24a9345d7908dc25ae403ee7
-F ext/fts3/fts3_write.c edf123f978fca3d26707452a380fa169849eb655
+F ext/fts3/fts3_write.c ec6bbf26bfa21e64b059535e46b3a8e57fb21f5c
 F ext/fts3/mkfts3amal.tcl 252ecb7fe6467854f2aa237bf2c390b74e71f100
 F ext/icu/README.txt 3b130aa66e7a681136f6add198b076a2f90d1e33
 F ext/icu/icu.c 12e763d288d23b5a49de37caa30737b971a2f1e2
@@ -772,7 +772,7 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P f29c8fcade4aadeae3824975cf59f306c11c906b
-R a419bf1bcdd810be07b904f21b0a1ef0
+P 45c051e78651d8204c17cecdda2bde705698881f
+R f882843f6b95cfb6a8f2fd130e122bb3
 U dan
-Z 4e40dbade582f444c0b93ffcad88c385
+Z b8988750cf7cc171c22183eb295bebe6
diff --git a/manifest.uuid b/manifest.uuid
index 7c64886602..5563c3807c 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-45c051e78651d8204c17cecdda2bde705698881f
\ No newline at end of file
+2fe579e778b75fbf503c02e01e5424c1926f2b49
\ No newline at end of file