diff options
Diffstat (limited to 'ext/lsm1/lsm_vtab.c')
| -rw-r--r-- | ext/lsm1/lsm_vtab.c | 1084 |
1 files changed, 0 insertions, 1084 deletions
diff --git a/ext/lsm1/lsm_vtab.c b/ext/lsm1/lsm_vtab.c deleted file mode 100644 index 8c21923e1..000000000 --- a/ext/lsm1/lsm_vtab.c +++ /dev/null @@ -1,1084 +0,0 @@ -/* -** 2015-11-16 -** -** The author disclaims copyright to this source code. In place of -** a legal notice, here is a blessing: -** -** May you do good and not evil. -** May you find forgiveness for yourself and forgive others. -** May you share freely, never taking more than you give. -** -************************************************************************* -** -** This file implements a virtual table for SQLite3 around the LSM -** storage engine from SQLite4. -** -** USAGE -** -** CREATE VIRTUAL TABLE demo USING lsm1(filename,key,keytype,value1,...); -** -** The filename parameter is the name of the LSM database file, which is -** separate and distinct from the SQLite3 database file. -** -** The keytype must be one of: UINT, TEXT, BLOB. All keys must be of that -** one type. "UINT" means unsigned integer. The values may be of any -** SQLite datatype: BLOB, TEXT, INTEGER, FLOAT, or NULL. -** -** The virtual table contains read-only hidden columns: -** -** lsm1_key A BLOB which is the raw LSM key. If the "keytype" -** is BLOB or TEXT then this column is exactly the -** same as the key. For the UINT keytype, this column -** will be a variable-length integer encoding of the key. -** -** lsm1_value A BLOB which is the raw LSM value. All of the value -** columns are packed into this BLOB using the encoding -** described below. -** -** Attempts to write values into the lsm1_key and lsm1_value columns are -** silently ignored. -** -** EXAMPLE -** -** The virtual table declared this way: -** -** CREATE VIRTUAL TABLE demo2 USING lsm1('x.lsm',id,UINT,a,b,c,d); -** -** Results in a new virtual table named "demo2" that acts as if it has -** the following schema: -** -** CREATE TABLE demo2( -** id UINT PRIMARY KEY ON CONFLICT REPLACE, -** a ANY, -** b ANY, -** c ANY, -** d ANY, -** lsm1_key BLOB HIDDEN, -** lsm1_value BLOB HIDDEN -** ) WITHOUT ROWID; -** -** -** -** INTERNALS -** -** The key encoding for BLOB and TEXT is just a copy of the blob or text. -** UTF-8 is used for text. The key encoding for UINT is the variable-length -** integer format at https://sqlite.org/src4/doc/trunk/www/varint.wiki. -** -** The values are encoded as a single blob (since that is what lsm stores as -** its content). There is a "type integer" followed by "content" for each -** value, alternating back and forth. The content might be empty. -** -** TYPE1 CONTENT1 TYPE2 CONTENT2 TYPE3 CONTENT3 .... -** -** Each "type integer" is encoded as a variable-length integer in the -** format of the link above. Let the type integer be T. The actual -** datatype is an integer 0-5 equal to T%6. Values 1 through 5 correspond -** to SQLITE_INTEGER through SQLITE_NULL. The size of the content in bytes -** is T/6. Type value 0 means that the value is an integer whose actual -** values is T/6 and there is no content. The type-value-0 integer format -** only works for integers in the range of 0 through 40. -** -** There is no content for NULL or type-0 integers. For BLOB and TEXT -** values, the content is the blob data or the UTF-8 text data. For -** non-negative integers X, the content is a variable-length integer X*2. -** For negative integers Y, the content is varaible-length integer (1-Y)*2+1. -** For FLOAT values, the content is the IEEE754 floating point value in -** native byte-order. This means that FLOAT values will be corrupted when -** database file is moved between big-endian and little-endian machines. -*/ -#include "sqlite3ext.h" -SQLITE_EXTENSION_INIT1 -#include "lsm.h" -#include <assert.h> -#include <string.h> - -/* Forward declaration of subclasses of virtual table objects */ -typedef struct lsm1_vtab lsm1_vtab; -typedef struct lsm1_cursor lsm1_cursor; -typedef struct lsm1_vblob lsm1_vblob; - -/* Primitive types */ -typedef unsigned char u8; -typedef unsigned int u32; -typedef sqlite3_uint64 u64; - -/* An open connection to an LSM table */ -struct lsm1_vtab { - sqlite3_vtab base; /* Base class - must be first */ - lsm_db *pDb; /* Open connection to the LSM table */ - u8 keyType; /* SQLITE_BLOB, _TEXT, or _INTEGER */ - u32 nVal; /* Number of value columns */ -}; - - -/* lsm1_cursor is a subclass of sqlite3_vtab_cursor which will -** serve as the underlying representation of a cursor that scans -** over rows of the result -*/ -struct lsm1_cursor { - sqlite3_vtab_cursor base; /* Base class - must be first */ - lsm_cursor *pLsmCur; /* The LSM cursor */ - u8 isDesc; /* 0: scan forward. 1: scan reverse */ - u8 atEof; /* True if the scan is complete */ - u8 bUnique; /* True if no more than one row of output */ - u8 *zData; /* Content of the current row */ - u32 nData; /* Number of bytes in the current row */ - u8 *aeType; /* Types for all column values */ - u32 *aiOfst; /* Offsets to the various fields */ - u32 *aiLen; /* Length of each field */ - u8 *pKey2; /* Loop termination key, or NULL */ - u32 nKey2; /* Length of the loop termination key */ -}; - -/* An extensible buffer object. -** -** Content can be appended. Space to hold new content is automatically -** allocated. -*/ -struct lsm1_vblob { - u8 *a; /* Space to hold content, from sqlite3_malloc64() */ - u64 n; /* Bytes of space used */ - u64 nAlloc; /* Bytes of space allocated */ - u8 errNoMem; /* True if a memory allocation error has been seen */ -}; - -#if defined(__GNUC__) -# define LSM1_NOINLINE __attribute__((noinline)) -#elif defined(_MSC_VER) && _MSC_VER>=1310 -# define LSM1_NOINLINE __declspec(noinline) -#else -# define LSM1_NOINLINE -#endif - - -/* Increase the available space in the vblob object so that it can hold -** at least N more bytes. Return the number of errors. -*/ -static int lsm1VblobEnlarge(lsm1_vblob *p, u32 N){ - if( p->n+N>p->nAlloc ){ - if( p->errNoMem ) return 1; - p->nAlloc += N + (p->nAlloc ? p->nAlloc : N); - p->a = sqlite3_realloc64(p->a, p->nAlloc); - if( p->a==0 ){ - p->n = 0; - p->nAlloc = 0; - p->errNoMem = 1; - return 1; - } - p->nAlloc = sqlite3_msize(p->a); - } - return 0; -} - -/* Append N bytes to a vblob after first enlarging it */ -static LSM1_NOINLINE void lsm1VblobEnlargeAndAppend( - lsm1_vblob *p, - const u8 *pData, - u32 N -){ - if( p->n+N>p->nAlloc && lsm1VblobEnlarge(p, N) ) return; - memcpy(p->a+p->n, pData, N); - p->n += N; -} - -/* Append N bytes to a vblob */ -static void lsm1VblobAppend(lsm1_vblob *p, const u8 *pData, u32 N){ - sqlite3_int64 n = p->n; - if( n+N>p->nAlloc ){ - lsm1VblobEnlargeAndAppend(p, pData, N); - }else{ - p->n += N; - memcpy(p->a+n, pData, N); - } -} - -/* append text to a vblob */ -static void lsm1VblobAppendText(lsm1_vblob *p, const char *z){ - lsm1VblobAppend(p, (u8*)z, (u32)strlen(z)); -} - -/* Dequote the string */ -static void lsm1Dequote(char *z){ - int j; - char cQuote = z[0]; - size_t i, n; - - if( cQuote!='\'' && cQuote!='"' ) return; - n = strlen(z); - if( n<2 || z[n-1]!=z[0] ) return; - for(i=1, j=0; i<n-1; i++){ - if( z[i]==cQuote && z[i+1]==cQuote ) i++; - z[j++] = z[i]; - } - z[j] = 0; -} - - -/* -** The lsm1Connect() method is invoked to create a new -** lsm1_vtab that describes the virtual table. -*/ -static int lsm1Connect( - sqlite3 *db, - void *pAux, - int argc, const char *const*argv, - sqlite3_vtab **ppVtab, - char **pzErr -){ - lsm1_vtab *pNew; - int rc; - char *zFilename; - u8 keyType = 0; - int i; - lsm1_vblob sql; - static const char *azTypes[] = { "UINT", "TEXT", "BLOB" }; - static const u8 aeTypes[] = { SQLITE_INTEGER, SQLITE_TEXT, SQLITE_BLOB }; - static const char *azArgName[] = {"filename", "key", "key type", "value1" }; - - for(i=0; i<sizeof(azArgName)/sizeof(azArgName[0]); i++){ - if( argc<i+4 || argv[i+3]==0 || argv[i+3][0]==0 ){ - *pzErr = sqlite3_mprintf("%s (%r) argument missing", - azArgName[i], i+1); - return SQLITE_ERROR; - } - } - for(i=0; i<sizeof(azTypes)/sizeof(azTypes[0]); i++){ - if( sqlite3_stricmp(azTypes[i],argv[5])==0 ){ - keyType = aeTypes[i]; - break; - } - } - if( keyType==0 ){ - *pzErr = sqlite3_mprintf("key type should be INT, TEXT, or BLOB"); - return SQLITE_ERROR; - } - *ppVtab = sqlite3_malloc( sizeof(*pNew) ); - pNew = (lsm1_vtab*)*ppVtab; - if( pNew==0 ){ - return SQLITE_NOMEM; - } - memset(pNew, 0, sizeof(*pNew)); - pNew->keyType = keyType; - rc = lsm_new(0, &pNew->pDb); - if( rc ){ - *pzErr = sqlite3_mprintf("lsm_new failed with error code %d", rc); - rc = SQLITE_ERROR; - goto connect_failed; - } - zFilename = sqlite3_mprintf("%s", argv[3]); - lsm1Dequote(zFilename); - rc = lsm_open(pNew->pDb, zFilename); - sqlite3_free(zFilename); - if( rc ){ - *pzErr = sqlite3_mprintf("lsm_open failed with %d", rc); - rc = SQLITE_ERROR; - goto connect_failed; - } - - memset(&sql, 0, sizeof(sql)); - lsm1VblobAppendText(&sql, "CREATE TABLE x("); - lsm1VblobAppendText(&sql, argv[4]); - lsm1VblobAppendText(&sql, " "); - lsm1VblobAppendText(&sql, argv[5]); - lsm1VblobAppendText(&sql, " PRIMARY KEY"); - for(i=6; i<argc; i++){ - lsm1VblobAppendText(&sql, ", "); - lsm1VblobAppendText(&sql, argv[i]); - pNew->nVal++; - } - lsm1VblobAppendText(&sql, - ", lsm1_command HIDDEN" - ", lsm1_key HIDDEN" - ", lsm1_value HIDDEN) WITHOUT ROWID"); - lsm1VblobAppend(&sql, (u8*)"", 1); - if( sql.errNoMem ){ - rc = SQLITE_NOMEM; - goto connect_failed; - } - rc = sqlite3_declare_vtab(db, (const char*)sql.a); - sqlite3_free(sql.a); - -connect_failed: - if( rc!=SQLITE_OK ){ - if( pNew ){ - if( pNew->pDb ) lsm_close(pNew->pDb); - sqlite3_free(pNew); - } - *ppVtab = 0; - } - return rc; -} - -/* -** This method is the destructor for lsm1_cursor objects. -*/ -static int lsm1Disconnect(sqlite3_vtab *pVtab){ - lsm1_vtab *p = (lsm1_vtab*)pVtab; - lsm_close(p->pDb); - sqlite3_free(p); - return SQLITE_OK; -} - -/* -** Constructor for a new lsm1_cursor object. -*/ -static int lsm1Open(sqlite3_vtab *pVtab, sqlite3_vtab_cursor **ppCursor){ - lsm1_vtab *p = (lsm1_vtab*)pVtab; - lsm1_cursor *pCur; - int rc; - pCur = sqlite3_malloc64( sizeof(*pCur) - + p->nVal*(sizeof(pCur->aiOfst)+sizeof(pCur->aiLen)+1) ); - if( pCur==0 ) return SQLITE_NOMEM; - memset(pCur, 0, sizeof(*pCur)); - pCur->aiOfst = (u32*)&pCur[1]; - pCur->aiLen = &pCur->aiOfst[p->nVal]; - pCur->aeType = (u8*)&pCur->aiLen[p->nVal]; - *ppCursor = &pCur->base; - rc = lsm_csr_open(p->pDb, &pCur->pLsmCur); - if( rc==LSM_OK ){ - rc = SQLITE_OK; - }else{ - sqlite3_free(pCur); - *ppCursor = 0; - rc = SQLITE_ERROR; - } - return rc; -} - -/* -** Destructor for a lsm1_cursor. -*/ -static int lsm1Close(sqlite3_vtab_cursor *cur){ - lsm1_cursor *pCur = (lsm1_cursor*)cur; - sqlite3_free(pCur->pKey2); - lsm_csr_close(pCur->pLsmCur); - sqlite3_free(pCur); - return SQLITE_OK; -} - - -/* -** Advance a lsm1_cursor to its next row of output. -*/ -static int lsm1Next(sqlite3_vtab_cursor *cur){ - lsm1_cursor *pCur = (lsm1_cursor*)cur; - int rc = LSM_OK; - if( pCur->bUnique ){ - pCur->atEof = 1; - }else{ - if( pCur->isDesc ){ - rc = lsm_csr_prev(pCur->pLsmCur); - }else{ - rc = lsm_csr_next(pCur->pLsmCur); - } - if( rc==LSM_OK && lsm_csr_valid(pCur->pLsmCur)==0 ){ - pCur->atEof = 1; - } - if( pCur->pKey2 && pCur->atEof==0 ){ - const u8 *pVal; - u32 nVal; - assert( pCur->isDesc==0 ); - rc = lsm_csr_key(pCur->pLsmCur, (const void**)&pVal, (int*)&nVal); - if( rc==LSM_OK ){ - u32 len = pCur->nKey2; - int c; - if( len>nVal ) len = nVal; - c = memcmp(pVal, pCur->pKey2, len); - if( c==0 ) c = nVal - pCur->nKey2; - if( c>0 ) pCur->atEof = 1; - } - } - pCur->zData = 0; - } - return rc==LSM_OK ? SQLITE_OK : SQLITE_ERROR; -} - -/* -** Return TRUE if the cursor has been moved off of the last -** row of output. -*/ -static int lsm1Eof(sqlite3_vtab_cursor *cur){ - lsm1_cursor *pCur = (lsm1_cursor*)cur; - return pCur->atEof; -} - -/* -** Rowids are not supported by the underlying virtual table. So always -** return 0 for the rowid. -*/ -static int lsm1Rowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){ - *pRowid = 0; - return SQLITE_OK; -} - -/* -** Type prefixes on LSM keys -*/ -#define LSM1_TYPE_NEGATIVE 0 -#define LSM1_TYPE_POSITIVE 1 -#define LSM1_TYPE_TEXT 2 -#define LSM1_TYPE_BLOB 3 - -/* -** Write a 32-bit unsigned integer as 4 big-endian bytes. -*/ -static void varintWrite32(unsigned char *z, unsigned int y){ - z[0] = (unsigned char)(y>>24); - z[1] = (unsigned char)(y>>16); - z[2] = (unsigned char)(y>>8); - z[3] = (unsigned char)(y); -} - -/* -** Write a varint into z[]. The buffer z[] must be at least 9 characters -** long to accommodate the largest possible varint. Return the number of -** bytes of z[] used. -*/ -static int lsm1PutVarint64(unsigned char *z, sqlite3_uint64 x){ - unsigned int w, y; - if( x<=240 ){ - z[0] = (unsigned char)x; - return 1; - } - if( x<=2287 ){ - y = (unsigned int)(x - 240); - z[0] = (unsigned char)(y/256 + 241); - z[1] = (unsigned char)(y%256); - return 2; - } - if( x<=67823 ){ - y = (unsigned int)(x - 2288); - z[0] = 249; - z[1] = (unsigned char)(y/256); - z[2] = (unsigned char)(y%256); - return 3; - } - y = (unsigned int)x; - w = (unsigned int)(x>>32); - if( w==0 ){ - if( y<=16777215 ){ - z[0] = 250; - z[1] = (unsigned char)(y>>16); - z[2] = (unsigned char)(y>>8); - z[3] = (unsigned char)(y); - return 4; - } - z[0] = 251; - varintWrite32(z+1, y); - return 5; - } - if( w<=255 ){ - z[0] = 252; - z[1] = (unsigned char)w; - varintWrite32(z+2, y); - return 6; - } - if( w<=65535 ){ - z[0] = 253; - z[1] = (unsigned char)(w>>8); - z[2] = (unsigned char)w; - varintWrite32(z+3, y); - return 7; - } - if( w<=16777215 ){ - z[0] = 254; - z[1] = (unsigned char)(w>>16); - z[2] = (unsigned char)(w>>8); - z[3] = (unsigned char)w; - varintWrite32(z+4, y); - return 8; - } - z[0] = 255; - varintWrite32(z+1, w); - varintWrite32(z+5, y); - return 9; -} - -/* Append non-negative integer x as a variable-length integer. -*/ -static void lsm1VblobAppendVarint(lsm1_vblob *p, sqlite3_uint64 x){ - sqlite3_int64 n = p->n; - if( n+9>p->nAlloc && lsm1VblobEnlarge(p, 9) ) return; - p->n += lsm1PutVarint64(p->a+p->n, x); -} - -/* -** Decode the varint in the first n bytes z[]. Write the integer value -** into *pResult and return the number of bytes in the varint. -** -** If the decode fails because there are not enough bytes in z[] then -** return 0; -*/ -static int lsm1GetVarint64( - const unsigned char *z, - int n, - sqlite3_uint64 *pResult -){ - unsigned int x; - if( n<1 ) return 0; - if( z[0]<=240 ){ - *pResult = z[0]; - return 1; - } - if( z[0]<=248 ){ - if( n<2 ) return 0; - *pResult = (z[0]-241)*256 + z[1] + 240; - return 2; - } - if( n<z[0]-246 ) return 0; - if( z[0]==249 ){ - *pResult = 2288 + 256*z[1] + z[2]; - return 3; - } - if( z[0]==250 ){ - *pResult = (z[1]<<16) + (z[2]<<8) + z[3]; - return 4; - } - x = (z[1]<<24) + (z[2]<<16) + (z[3]<<8) + z[4]; - if( z[0]==251 ){ - *pResult = x; - return 5; - } - if( z[0]==252 ){ - *pResult = (((sqlite3_uint64)x)<<8) + z[5]; - return 6; - } - if( z[0]==253 ){ - *pResult = (((sqlite3_uint64)x)<<16) + (z[5]<<8) + z[6]; - return 7; - } - if( z[0]==254 ){ - *pResult = (((sqlite3_uint64)x)<<24) + (z[5]<<16) + (z[6]<<8) + z[7]; - return 8; - } - *pResult = (((sqlite3_uint64)x)<<32) + - (0xffffffff & ((z[5]<<24) + (z[6]<<16) + (z[7]<<8) + z[8])); - return 9; -} - -/* Encoded a signed integer as a varint. Numbers close to zero uses fewer -** bytes than numbers far away from zero. However, the result is not in -** lexicographical order. -** -** Encoding: Non-negative integer X is encoding as an unsigned -** varint X*2. Negative integer Y is encoding as an unsigned -** varint (1-Y)*2 + 1. -*/ -static int lsm1PutSignedVarint64(u8 *z, sqlite3_int64 v){ - sqlite3_uint64 u; - if( v>=0 ){ - u = (sqlite3_uint64)v; - return lsm1PutVarint64(z, u*2); - }else{ - u = (sqlite3_uint64)(-1-v); - return lsm1PutVarint64(z, u*2+1); - } -} - -/* Decoded a signed varint. */ -static int lsm1GetSignedVarint64( - const unsigned char *z, - int n, - sqlite3_int64 *pResult -){ - sqlite3_uint64 u = 0; - n = lsm1GetVarint64(z, n, &u); - if( u&1 ){ - *pResult = -1 - (sqlite3_int64)(u>>1); - }else{ - *pResult = (sqlite3_int64)(u>>1); - } - return n; -} - - -/* -** Read the value part of the key-value pair and decode it into columns. -*/ -static int lsm1DecodeValues(lsm1_cursor *pCur){ - lsm1_vtab *pTab = (lsm1_vtab*)(pCur->base.pVtab); - int i, n; - int rc; - u8 eType; - sqlite3_uint64 v; - - if( pCur->zData ) return 1; - rc = lsm_csr_value(pCur->pLsmCur, (const void**)&pCur->zData, - (int*)&pCur->nData); - if( rc ) return 0; - for(i=n=0; i<pTab->nVal; i++){ - v = 0; - n += lsm1GetVarint64(pCur->zData+n, pCur->nData-n, &v); - pCur->aeType[i] = eType = (u8)(v%6); - if( eType==0 ){ - pCur->aiOfst[i] = (u32)(v/6); - pCur->aiLen[i] = 0; - }else{ - pCur->aiOfst[i] = n; - n += (pCur->aiLen[i] = (u32)(v/6)); - } - if( n>pCur->nData ) break; - } - if( i<pTab->nVal ){ - pCur->zData = 0; - return 0; - } - return 1; -} - -/* -** Return values of columns for the row at which the lsm1_cursor -** is currently pointing. -*/ -static int lsm1Column( - sqlite3_vtab_cursor *cur, /* The cursor */ - sqlite3_context *ctx, /* First argument to sqlite3_result_...() */ - int i /* Which column to return */ -){ - lsm1_cursor *pCur = (lsm1_cursor*)cur; - lsm1_vtab *pTab = (lsm1_vtab*)(cur->pVtab); - if( i==0 ){ - /* The key column */ - const void *pVal; - int nVal; - if( lsm_csr_key(pCur->pLsmCur, &pVal, &nVal)==LSM_OK ){ - if( pTab->keyType==SQLITE_BLOB ){ - sqlite3_result_blob(ctx, pVal, nVal, SQLITE_TRANSIENT); - }else if( pTab->keyType==SQLITE_TEXT ){ - sqlite3_result_text(ctx,(const char*)pVal, nVal, SQLITE_TRANSIENT); - }else{ - const unsigned char *z = (const unsigned char*)pVal; - sqlite3_uint64 v1; - lsm1GetVarint64(z, nVal, &v1); - sqlite3_result_int64(ctx, (sqlite3_int64)v1); - } - } - }else if( i>pTab->nVal ){ - if( i==pTab->nVal+2 ){ /* lsm1_key */ - const void *pVal; - int nVal; - if( lsm_csr_key(pCur->pLsmCur, &pVal, &nVal)==LSM_OK ){ - sqlite3_result_blob(ctx, pVal, nVal, SQLITE_TRANSIENT); - } - }else if( i==pTab->nVal+3 ){ /* lsm1_value */ - const void *pVal; - int nVal; - if( lsm_csr_value(pCur->pLsmCur, &pVal, &nVal)==LSM_OK ){ - sqlite3_result_blob(ctx, pVal, nVal, SQLITE_TRANSIENT); - } - } - }else if( lsm1DecodeValues(pCur) ){ - /* The i-th value column (where leftmost is 1) */ - const u8 *zData; - u32 nData; - i--; - zData = pCur->zData + pCur->aiOfst[i]; - nData = pCur->aiLen[i]; - switch( pCur->aeType[i] ){ - case 0: { /* in-line integer */ - sqlite3_result_int(ctx, pCur->aiOfst[i]); - break; - } - case SQLITE_INTEGER: { - sqlite3_int64 v; - lsm1GetSignedVarint64(zData, nData, &v); - sqlite3_result_int64(ctx, v); - break; - } - case SQLITE_FLOAT: { - double v; - if( nData==sizeof(v) ){ - memcpy(&v, zData, sizeof(v)); - sqlite3_result_double(ctx, v); - } - break; - } - case SQLITE_TEXT: { - sqlite3_result_text(ctx, (const char*)zData, nData, SQLITE_TRANSIENT); - break; - } - case SQLITE_BLOB: { - sqlite3_result_blob(ctx, zData, nData, SQLITE_TRANSIENT); - break; - } - default: { - /* A NULL. Do nothing */ - } - } - } - return SQLITE_OK; -} - -/* Parameter "pValue" contains an SQL value that is to be used as -** a key in an LSM table. The type of the key is determined by -** "keyType". Extract the raw bytes used for the key in LSM1. -*/ -static void lsm1KeyFromValue( - int keyType, /* The key type */ - sqlite3_value *pValue, /* The key value */ - u8 *pBuf, /* Storage space for a generated key */ - const u8 **ppKey, /* OUT: the bytes of the key */ - int *pnKey /* OUT: size of the key */ -){ - if( keyType==SQLITE_BLOB ){ - *ppKey = (const u8*)sqlite3_value_blob(pValue); - *pnKey = sqlite3_value_bytes(pValue); - }else if( keyType==SQLITE_TEXT ){ - *ppKey = (const u8*)sqlite3_value_text(pValue); - *pnKey = sqlite3_value_bytes(pValue); - }else{ - sqlite3_int64 v = sqlite3_value_int64(pValue); - if( v<0 ) v = 0; - *pnKey = lsm1PutVarint64(pBuf, v); - *ppKey = pBuf; - } -} - -/* Move to the first row to return. -*/ -static int lsm1Filter( - sqlite3_vtab_cursor *pVtabCursor, - int idxNum, const char *idxStr, - int argc, sqlite3_value **argv -){ - lsm1_cursor *pCur = (lsm1_cursor *)pVtabCursor; - lsm1_vtab *pTab = (lsm1_vtab*)(pCur->base.pVtab); - int rc = LSM_OK; - int seekType = -1; - const u8 *pVal = 0; - int nVal; - u8 keyType = pTab->keyType; - u8 aKey1[16]; - - pCur->atEof = 1; - sqlite3_free(pCur->pKey2); - pCur->pKey2 = 0; - if( idxNum<99 ){ - lsm1KeyFromValue(keyType, argv[0], aKey1, &pVal, &nVal); - } - switch( idxNum ){ - case 0: { /* key==argv[0] */ - assert( argc==1 ); - seekType = LSM_SEEK_EQ; - pCur->isDesc = 0; - pCur->bUnique = 1; - break; - } - case 1: { /* key>=argv[0] AND key<=argv[1] */ - u8 aKey[12]; - seekType = LSM_SEEK_GE; - pCur->isDesc = 0; - pCur->bUnique = 0; - if( keyType==SQLITE_INTEGER ){ - sqlite3_int64 v = sqlite3_value_int64(argv[1]); - if( v<0 ) v = 0; - pCur->nKey2 = lsm1PutVarint64(aKey, (sqlite3_uint64)v); - pCur->pKey2 = sqlite3_malloc( pCur->nKey2 ); - if( pCur->pKey2==0 ) return SQLITE_NOMEM; - memcpy(pCur->pKey2, aKey, pCur->nKey2); - }else{ - pCur->nKey2 = sqlite3_value_bytes(argv[1]); - pCur->pKey2 = sqlite3_malloc( pCur->nKey2 ); - if( pCur->pKey2==0 ) return SQLITE_NOMEM; - if( keyType==SQLITE_BLOB ){ - memcpy(pCur->pKey2, sqlite3_value_blob(argv[1]), pCur->nKey2); - }else{ - memcpy(pCur->pKey2, sqlite3_value_text(argv[1]), pCur->nKey2); - } - } - break; - } - case 2: { /* key>=argv[0] */ - seekType = LSM_SEEK_GE; - pCur->isDesc = 0; - pCur->bUnique = 0; - break; - } - case 3: { /* key<=argv[0] */ - seekType = LSM_SEEK_LE; - pCur->isDesc = 1; - pCur->bUnique = 0; - break; - } - default: { /* full table scan */ - pCur->isDesc = 0; - pCur->bUnique = 0; - break; - } - } - if( pVal ){ - rc = lsm_csr_seek(pCur->pLsmCur, pVal, nVal, seekType); - }else{ - rc = lsm_csr_first(pCur->pLsmCur); - } - if( rc==LSM_OK && lsm_csr_valid(pCur->pLsmCur)!=0 ){ - pCur->atEof = 0; - } - return rc==LSM_OK ? SQLITE_OK : SQLITE_ERROR; -} - -/* -** Only comparisons against the key are allowed. The idxNum defines -** which comparisons are available: -** -** 0 key==?1 -** 1 key>=?1 AND key<=?2 -** 2 key>?1 or key>=?1 -** 3 key<?1 or key<=?1 -** 99 Full table scan only -*/ -static int lsm1BestIndex( - sqlite3_vtab *tab, - sqlite3_index_info *pIdxInfo -){ - int i; /* Loop over constraints */ - int idxNum = 99; /* The query plan */ - int nArg = 0; /* Number of arguments to xFilter */ - int argIdx = -1; /* Index of the key== constraint, or -1 if none */ - int iIdx2 = -1; /* The index of the second key */ - int omit1 = 0; - int omit2 = 0; - - const struct sqlite3_index_constraint *pConstraint; - pConstraint = pIdxInfo->aConstraint; - for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){ - if( pConstraint->usable==0 ) continue; - if( pConstraint->iColumn!=0 ) continue; - switch( pConstraint->op ){ - case SQLITE_INDEX_CONSTRAINT_EQ: { - if( idxNum>0 ){ - argIdx = i; - iIdx2 = -1; - idxNum = 0; - omit1 = 1; - } - break; - } - case SQLITE_INDEX_CONSTRAINT_GE: - case SQLITE_INDEX_CONSTRAINT_GT: { - if( idxNum==99 ){ - argIdx = i; - idxNum = 2; - omit1 = pConstraint->op==SQLITE_INDEX_CONSTRAINT_GE; - }else if( idxNum==3 ){ - iIdx2 = idxNum; - omit2 = omit1; - argIdx = i; - idxNum = 1; - omit1 = pConstraint->op==SQLITE_INDEX_CONSTRAINT_GE; - } - break; - } - case SQLITE_INDEX_CONSTRAINT_LE: - case SQLITE_INDEX_CONSTRAINT_LT: { - if( idxNum==99 ){ - argIdx = i; - idxNum = 3; - omit1 = pConstraint->op==SQLITE_INDEX_CONSTRAINT_LE; - }else if( idxNum==2 ){ - iIdx2 = i; - idxNum = 1; - omit1 = pConstraint->op==SQLITE_INDEX_CONSTRAINT_LE; - } - break; - } - } - } - if( argIdx>=0 ){ - pIdxInfo->aConstraintUsage[argIdx].argvIndex = ++nArg; - pIdxInfo->aConstraintUsage[argIdx].omit = omit1; - } - if( iIdx2>=0 ){ - pIdxInfo->aConstraintUsage[iIdx2].argvIndex = ++nArg; - pIdxInfo->aConstraintUsage[iIdx2].omit = omit2; - } - if( idxNum==0 ){ - pIdxInfo->estimatedCost = (double)1; - pIdxInfo->estimatedRows = 1; - pIdxInfo->orderByConsumed = 1; - }else if( idxNum==1 ){ - pIdxInfo->estimatedCost = (double)100; - pIdxInfo->estimatedRows = 100; - }else if( idxNum<99 ){ - pIdxInfo->estimatedCost = (double)5000; - pIdxInfo->estimatedRows = 5000; - }else{ - /* Full table scan */ - pIdxInfo->estimatedCost = (double)2147483647; - pIdxInfo->estimatedRows = 2147483647; - } - pIdxInfo->idxNum = idxNum; - return SQLITE_OK; -} - -/* -** The xUpdate method is normally used for INSERT, REPLACE, UPDATE, and -** DELETE. But this virtual table only supports INSERT and REPLACE. -** DELETE is accomplished by inserting a record with a value of NULL. -** UPDATE is achieved by using REPLACE. -*/ -int lsm1Update( - sqlite3_vtab *pVTab, - int argc, - sqlite3_value **argv, - sqlite_int64 *pRowid -){ - lsm1_vtab *p = (lsm1_vtab*)pVTab; - int nKey, nKey2; - int i; - int rc = LSM_OK; - const u8 *pKey, *pKey2; - unsigned char aKey[16]; - unsigned char pSpace[16]; - lsm1_vblob val; - - if( argc==1 ){ - /* DELETE the record whose key is argv[0] */ - lsm1KeyFromValue(p->keyType, argv[0], aKey, &pKey, &nKey); - lsm_delete(p->pDb, pKey, nKey); - return SQLITE_OK; - } - - if( sqlite3_value_type(argv[0])!=SQLITE_NULL ){ - /* An UPDATE */ - lsm1KeyFromValue(p->keyType, argv[0], aKey, &pKey, &nKey); - lsm1KeyFromValue(p->keyType, argv[1], pSpace, &pKey2, &nKey2); - if( nKey!=nKey2 || memcmp(pKey, pKey2, nKey)!=0 ){ - /* The UPDATE changes the PRIMARY KEY value. DELETE the old key */ - lsm_delete(p->pDb, pKey, nKey); - } - /* Fall through into the INSERT case to complete the UPDATE */ - } - - /* "INSERT INTO tab(lsm1_command) VALUES('....')" is used to implement - ** special commands. - */ - if( sqlite3_value_type(argv[3+p->nVal])!=SQLITE_NULL ){ - return SQLITE_OK; - } - lsm1KeyFromValue(p->keyType, argv[2], aKey, &pKey, &nKey); - memset(&val, 0, sizeof(val)); - for(i=0; i<p->nVal; i++){ - sqlite3_value *pArg = argv[3+i]; - u8 eType = sqlite3_value_type(pArg); - switch( eType ){ - case SQLITE_NULL: { - lsm1VblobAppendVarint(&val, SQLITE_NULL); - break; - } - case SQLITE_INTEGER: { - sqlite3_int64 v = sqlite3_value_int64(pArg); - if( v>=0 && v<=240/6 ){ - lsm1VblobAppendVarint(&val, v*6); - }else{ - int n = lsm1PutSignedVarint64(pSpace, v); - lsm1VblobAppendVarint(&val, SQLITE_INTEGER + n*6); - lsm1VblobAppend(&val, pSpace, n); - } - break; - } - case SQLITE_FLOAT: { - double r = sqlite3_value_double(pArg); - lsm1VblobAppendVarint(&val, SQLITE_FLOAT + 8*6); - lsm1VblobAppend(&val, (u8*)&r, sizeof(r)); - break; - } - case SQLITE_BLOB: { - int n = sqlite3_value_bytes(pArg); - lsm1VblobAppendVarint(&val, n*6 + SQLITE_BLOB); - lsm1VblobAppend(&val, sqlite3_value_blob(pArg), n); - break; - } - case SQLITE_TEXT: { - int n = sqlite3_value_bytes(pArg); - lsm1VblobAppendVarint(&val, n*6 + SQLITE_TEXT); - lsm1VblobAppend(&val, sqlite3_value_text(pArg), n); - break; - } - } - } - if( val.errNoMem ){ - return SQLITE_NOMEM; - } - rc = lsm_insert(p->pDb, pKey, nKey, val.a, val.n); - sqlite3_free(val.a); - return rc==LSM_OK ? SQLITE_OK : SQLITE_ERROR; -} - -/* Begin a transaction -*/ -static int lsm1Begin(sqlite3_vtab *pVtab){ - lsm1_vtab *p = (lsm1_vtab*)pVtab; - int rc = lsm_begin(p->pDb, 1); - return rc==LSM_OK ? SQLITE_OK : SQLITE_ERROR; -} - -/* Phase 1 of a transaction commit. -*/ -static int lsm1Sync(sqlite3_vtab *pVtab){ - return SQLITE_OK; -} - -/* Commit a transaction -*/ -static int lsm1Commit(sqlite3_vtab *pVtab){ - lsm1_vtab *p = (lsm1_vtab*)pVtab; - int rc = lsm_commit(p->pDb, 0); - return rc==LSM_OK ? SQLITE_OK : SQLITE_ERROR; -} - -/* Rollback a transaction -*/ -static int lsm1Rollback(sqlite3_vtab *pVtab){ - lsm1_vtab *p = (lsm1_vtab*)pVtab; - int rc = lsm_rollback(p->pDb, 0); - return rc==LSM_OK ? SQLITE_OK : SQLITE_ERROR; -} - -/* -** This following structure defines all the methods for the -** generate_lsm1 virtual table. -*/ -static sqlite3_module lsm1Module = { - 0, /* iVersion */ - lsm1Connect, /* xCreate */ - lsm1Connect, /* xConnect */ - lsm1BestIndex, /* xBestIndex */ - lsm1Disconnect, /* xDisconnect */ - lsm1Disconnect, /* xDestroy */ - lsm1Open, /* xOpen - open a cursor */ - lsm1Close, /* xClose - close a cursor */ - lsm1Filter, /* xFilter - configure scan constraints */ - lsm1Next, /* xNext - advance a cursor */ - lsm1Eof, /* xEof - check for end of scan */ - lsm1Column, /* xColumn - read data */ - lsm1Rowid, /* xRowid - read data */ - lsm1Update, /* xUpdate */ - lsm1Begin, /* xBegin */ - lsm1Sync, /* xSync */ - lsm1Commit, /* xCommit */ - lsm1Rollback, /* xRollback */ - 0, /* xFindMethod */ - 0, /* xRename */ - 0, /* xSavepoint */ - 0, /* xRelease */ - 0, /* xRollbackTo */ - 0, /* xShadowName */ - 0 /* xIntegrity */ -}; - - -#ifdef _WIN32 -__declspec(dllexport) -#endif -int sqlite3_lsm_init( - sqlite3 *db, - char **pzErrMsg, - const sqlite3_api_routines *pApi -){ - int rc = SQLITE_OK; - SQLITE_EXTENSION_INIT2(pApi); - rc = sqlite3_create_module(db, "lsm1", &lsm1Module, 0); - return rc; -} |