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Diffstat (limited to 'database/sqlite/sqlite3recover.c')
| -rw-r--r-- | database/sqlite/sqlite3recover.c | 2872 |
1 files changed, 2872 insertions, 0 deletions
diff --git a/database/sqlite/sqlite3recover.c b/database/sqlite/sqlite3recover.c new file mode 100644 index 000000000..3dae0b7a9 --- /dev/null +++ b/database/sqlite/sqlite3recover.c @@ -0,0 +1,2872 @@ +/* +** 2022-08-27 +** +** 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. +** +************************************************************************* +** +*/ + +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wsign-compare" +#include "sqlite3recover.h" +#include <assert.h> +#include <string.h> + +#ifndef SQLITE_OMIT_VIRTUALTABLE + +/* +** Declaration for public API function in file dbdata.c. This may be called +** with NULL as the final two arguments to register the sqlite_dbptr and +** sqlite_dbdata virtual tables with a database handle. +*/ +#ifdef _WIN32 +__declspec(dllexport) +#endif +int sqlite3_dbdata_init(sqlite3*, char**, const sqlite3_api_routines*); + +typedef unsigned int u32; +typedef unsigned char u8; +typedef sqlite3_int64 i64; + +typedef struct RecoverTable RecoverTable; +typedef struct RecoverColumn RecoverColumn; + +/* +** When recovering rows of data that can be associated with table +** definitions recovered from the sqlite_schema table, each table is +** represented by an instance of the following object. +** +** iRoot: +** The root page in the original database. Not necessarily (and usually +** not) the same in the recovered database. +** +** zTab: +** Name of the table. +** +** nCol/aCol[]: +** aCol[] is an array of nCol columns. In the order in which they appear +** in the table. +** +** bIntkey: +** Set to true for intkey tables, false for WITHOUT ROWID. +** +** iRowidBind: +** Each column in the aCol[] array has associated with it the index of +** the bind parameter its values will be bound to in the INSERT statement +** used to construct the output database. If the table does has a rowid +** but not an INTEGER PRIMARY KEY column, then iRowidBind contains the +** index of the bind paramater to which the rowid value should be bound. +** Otherwise, it contains -1. If the table does contain an INTEGER PRIMARY +** KEY column, then the rowid value should be bound to the index associated +** with the column. +** +** pNext: +** All RecoverTable objects used by the recovery operation are allocated +** and populated as part of creating the recovered database schema in +** the output database, before any non-schema data are recovered. They +** are then stored in a singly-linked list linked by this variable beginning +** at sqlite3_recover.pTblList. +*/ +struct RecoverTable { + u32 iRoot; /* Root page in original database */ + char *zTab; /* Name of table */ + int nCol; /* Number of columns in table */ + RecoverColumn *aCol; /* Array of columns */ + int bIntkey; /* True for intkey, false for without rowid */ + int iRowidBind; /* If >0, bind rowid to INSERT here */ + RecoverTable *pNext; +}; + +/* +** Each database column is represented by an instance of the following object +** stored in the RecoverTable.aCol[] array of the associated table. +** +** iField: +** The index of the associated field within database records. Or -1 if +** there is no associated field (e.g. for virtual generated columns). +** +** iBind: +** The bind index of the INSERT statement to bind this columns values +** to. Or 0 if there is no such index (iff (iField<0)). +** +** bIPK: +** True if this is the INTEGER PRIMARY KEY column. +** +** zCol: +** Name of column. +** +** eHidden: +** A RECOVER_EHIDDEN_* constant value (see below for interpretation of each). +*/ +struct RecoverColumn { + int iField; /* Field in record on disk */ + int iBind; /* Binding to use in INSERT */ + int bIPK; /* True for IPK column */ + char *zCol; + int eHidden; +}; + +#define RECOVER_EHIDDEN_NONE 0 /* Normal database column */ +#define RECOVER_EHIDDEN_HIDDEN 1 /* Column is __HIDDEN__ */ +#define RECOVER_EHIDDEN_VIRTUAL 2 /* Virtual generated column */ +#define RECOVER_EHIDDEN_STORED 3 /* Stored generated column */ + +/* +** Bitmap object used to track pages in the input database. Allocated +** and manipulated only by the following functions: +** +** recoverBitmapAlloc() +** recoverBitmapFree() +** recoverBitmapSet() +** recoverBitmapQuery() +** +** nPg: +** Largest page number that may be stored in the bitmap. The range +** of valid keys is 1 to nPg, inclusive. +** +** aElem[]: +** Array large enough to contain a bit for each key. For key value +** iKey, the associated bit is the bit (iKey%32) of aElem[iKey/32]. +** In other words, the following is true if bit iKey is set, or +** false if it is clear: +** +** (aElem[iKey/32] & (1 << (iKey%32))) ? 1 : 0 +*/ +typedef struct RecoverBitmap RecoverBitmap; +struct RecoverBitmap { + i64 nPg; /* Size of bitmap */ + u32 aElem[1]; /* Array of 32-bit bitmasks */ +}; + +/* +** State variables (part of the sqlite3_recover structure) used while +** recovering data for tables identified in the recovered schema (state +** RECOVER_STATE_WRITING). +*/ +typedef struct RecoverStateW1 RecoverStateW1; +struct RecoverStateW1 { + sqlite3_stmt *pTbls; + sqlite3_stmt *pSel; + sqlite3_stmt *pInsert; + int nInsert; + + RecoverTable *pTab; /* Table currently being written */ + int nMax; /* Max column count in any schema table */ + sqlite3_value **apVal; /* Array of nMax values */ + int nVal; /* Number of valid entries in apVal[] */ + int bHaveRowid; + i64 iRowid; + i64 iPrevPage; + int iPrevCell; +}; + +/* +** State variables (part of the sqlite3_recover structure) used while +** recovering data destined for the lost and found table (states +** RECOVER_STATE_LOSTANDFOUND[123]). +*/ +typedef struct RecoverStateLAF RecoverStateLAF; +struct RecoverStateLAF { + RecoverBitmap *pUsed; + i64 nPg; /* Size of db in pages */ + sqlite3_stmt *pAllAndParent; + sqlite3_stmt *pMapInsert; + sqlite3_stmt *pMaxField; + sqlite3_stmt *pUsedPages; + sqlite3_stmt *pFindRoot; + sqlite3_stmt *pInsert; /* INSERT INTO lost_and_found ... */ + sqlite3_stmt *pAllPage; + sqlite3_stmt *pPageData; + sqlite3_value **apVal; + int nMaxField; +}; + +/* +** Main recover handle structure. +*/ +struct sqlite3_recover { + /* Copies of sqlite3_recover_init[_sql]() parameters */ + sqlite3 *dbIn; /* Input database */ + char *zDb; /* Name of input db ("main" etc.) */ + char *zUri; /* URI for output database */ + void *pSqlCtx; /* SQL callback context */ + int (*xSql)(void*,const char*); /* Pointer to SQL callback function */ + + /* Values configured by sqlite3_recover_config() */ + char *zStateDb; /* State database to use (or NULL) */ + char *zLostAndFound; /* Name of lost-and-found table (or NULL) */ + int bFreelistCorrupt; /* SQLITE_RECOVER_FREELIST_CORRUPT setting */ + int bRecoverRowid; /* SQLITE_RECOVER_ROWIDS setting */ + int bSlowIndexes; /* SQLITE_RECOVER_SLOWINDEXES setting */ + + int pgsz; + int detected_pgsz; + int nReserve; + u8 *pPage1Disk; + u8 *pPage1Cache; + + /* Error code and error message */ + int errCode; /* For sqlite3_recover_errcode() */ + char *zErrMsg; /* For sqlite3_recover_errmsg() */ + + int eState; + int bCloseTransaction; + + /* Variables used with eState==RECOVER_STATE_WRITING */ + RecoverStateW1 w1; + + /* Variables used with states RECOVER_STATE_LOSTANDFOUND[123] */ + RecoverStateLAF laf; + + /* Fields used within sqlite3_recover_run() */ + sqlite3 *dbOut; /* Output database */ + sqlite3_stmt *pGetPage; /* SELECT against input db sqlite_dbdata */ + RecoverTable *pTblList; /* List of tables recovered from schema */ +}; + +/* +** The various states in which an sqlite3_recover object may exist: +** +** RECOVER_STATE_INIT: +** The object is initially created in this state. sqlite3_recover_step() +** has yet to be called. This is the only state in which it is permitted +** to call sqlite3_recover_config(). +** +** RECOVER_STATE_WRITING: +** +** RECOVER_STATE_LOSTANDFOUND1: +** State to populate the bitmap of pages used by other tables or the +** database freelist. +** +** RECOVER_STATE_LOSTANDFOUND2: +** Populate the recovery.map table - used to figure out a "root" page +** for each lost page from in the database from which records are +** extracted. +** +** RECOVER_STATE_LOSTANDFOUND3: +** Populate the lost-and-found table itself. +*/ +#define RECOVER_STATE_INIT 0 +#define RECOVER_STATE_WRITING 1 +#define RECOVER_STATE_LOSTANDFOUND1 2 +#define RECOVER_STATE_LOSTANDFOUND2 3 +#define RECOVER_STATE_LOSTANDFOUND3 4 +#define RECOVER_STATE_SCHEMA2 5 +#define RECOVER_STATE_DONE 6 + + +/* +** Global variables used by this extension. +*/ +typedef struct RecoverGlobal RecoverGlobal; +struct RecoverGlobal { + const sqlite3_io_methods *pMethods; + sqlite3_recover *p; +}; +static RecoverGlobal recover_g; + +/* +** Use this static SQLite mutex to protect the globals during the +** first call to sqlite3_recover_step(). +*/ +#define RECOVER_MUTEX_ID SQLITE_MUTEX_STATIC_APP2 + + +/* +** Default value for SQLITE_RECOVER_ROWIDS (sqlite3_recover.bRecoverRowid). +*/ +#define RECOVER_ROWID_DEFAULT 1 + +/* +** Mutex handling: +** +** recoverEnterMutex() - Enter the recovery mutex +** recoverLeaveMutex() - Leave the recovery mutex +** recoverAssertMutexHeld() - Assert that the recovery mutex is held +*/ +#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE==0 +# define recoverEnterMutex() +# define recoverLeaveMutex() +#else +static void recoverEnterMutex(void){ + sqlite3_mutex_enter(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)); +} +static void recoverLeaveMutex(void){ + sqlite3_mutex_leave(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)); +} +#endif +#if SQLITE_THREADSAFE+0>=1 && defined(SQLITE_DEBUG) +static void recoverAssertMutexHeld(void){ + assert( sqlite3_mutex_held(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)) ); +} +#else +# define recoverAssertMutexHeld() +#endif + + +/* +** Like strlen(). But handles NULL pointer arguments. +*/ +static int recoverStrlen(const char *zStr){ + if( zStr==0 ) return 0; + return (int)(strlen(zStr)&0x7fffffff); +} + +/* +** This function is a no-op if the recover handle passed as the first +** argument already contains an error (if p->errCode!=SQLITE_OK). +** +** Otherwise, an attempt is made to allocate, zero and return a buffer nByte +** bytes in size. If successful, a pointer to the new buffer is returned. Or, +** if an OOM error occurs, NULL is returned and the handle error code +** (p->errCode) set to SQLITE_NOMEM. +*/ +static void *recoverMalloc(sqlite3_recover *p, i64 nByte){ + void *pRet = 0; + assert( nByte>0 ); + if( p->errCode==SQLITE_OK ){ + pRet = sqlite3_malloc64(nByte); + if( pRet ){ + memset(pRet, 0, nByte); + }else{ + p->errCode = SQLITE_NOMEM; + } + } + return pRet; +} + +/* +** Set the error code and error message for the recover handle passed as +** the first argument. The error code is set to the value of parameter +** errCode. +** +** Parameter zFmt must be a printf() style formatting string. The handle +** error message is set to the result of using any trailing arguments for +** parameter substitutions in the formatting string. +** +** For example: +** +** recoverError(p, SQLITE_ERROR, "no such table: %s", zTablename); +*/ +static int recoverError( + sqlite3_recover *p, + int errCode, + const char *zFmt, ... +){ + char *z = 0; + va_list ap; + va_start(ap, zFmt); + if( zFmt ){ + z = sqlite3_vmprintf(zFmt, ap); + va_end(ap); + } + sqlite3_free(p->zErrMsg); + p->zErrMsg = z; + p->errCode = errCode; + return errCode; +} + + +/* +** This function is a no-op if p->errCode is initially other than SQLITE_OK. +** In this case it returns NULL. +** +** Otherwise, an attempt is made to allocate and return a bitmap object +** large enough to store a bit for all page numbers between 1 and nPg, +** inclusive. The bitmap is initially zeroed. +*/ +static RecoverBitmap *recoverBitmapAlloc(sqlite3_recover *p, i64 nPg){ + int nElem = (nPg+1+31) / 32; + int nByte = sizeof(RecoverBitmap) + nElem*sizeof(u32); + RecoverBitmap *pRet = (RecoverBitmap*)recoverMalloc(p, nByte); + + if( pRet ){ + pRet->nPg = nPg; + } + return pRet; +} + +/* +** Free a bitmap object allocated by recoverBitmapAlloc(). +*/ +static void recoverBitmapFree(RecoverBitmap *pMap){ + sqlite3_free(pMap); +} + +/* +** Set the bit associated with page iPg in bitvec pMap. +*/ +static void recoverBitmapSet(RecoverBitmap *pMap, i64 iPg){ + if( iPg<=pMap->nPg ){ + int iElem = (iPg / 32); + int iBit = (iPg % 32); + pMap->aElem[iElem] |= (((u32)1) << iBit); + } +} + +/* +** Query bitmap object pMap for the state of the bit associated with page +** iPg. Return 1 if it is set, or 0 otherwise. +*/ +static int recoverBitmapQuery(RecoverBitmap *pMap, i64 iPg){ + int ret = 1; + if( iPg<=pMap->nPg && iPg>0 ){ + int iElem = (iPg / 32); + int iBit = (iPg % 32); + ret = (pMap->aElem[iElem] & (((u32)1) << iBit)) ? 1 : 0; + } + return ret; +} + +/* +** Set the recover handle error to the error code and message returned by +** calling sqlite3_errcode() and sqlite3_errmsg(), respectively, on database +** handle db. +*/ +static int recoverDbError(sqlite3_recover *p, sqlite3 *db){ + return recoverError(p, sqlite3_errcode(db), "%s", sqlite3_errmsg(db)); +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). +** +** Otherwise, it attempts to prepare the SQL statement in zSql against +** database handle db. If successful, the statement handle is returned. +** Or, if an error occurs, NULL is returned and an error left in the +** recover handle. +*/ +static sqlite3_stmt *recoverPrepare( + sqlite3_recover *p, + sqlite3 *db, + const char *zSql +){ + sqlite3_stmt *pStmt = 0; + if( p->errCode==SQLITE_OK ){ + if( sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0) ){ + recoverDbError(p, db); + } + } + return pStmt; +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). +** +** Otherwise, argument zFmt is used as a printf() style format string, +** along with any trailing arguments, to create an SQL statement. This +** SQL statement is prepared against database handle db and, if successful, +** the statment handle returned. Or, if an error occurs - either during +** the printf() formatting or when preparing the resulting SQL - an +** error code and message are left in the recover handle. +*/ +static sqlite3_stmt *recoverPreparePrintf( + sqlite3_recover *p, + sqlite3 *db, + const char *zFmt, ... +){ + sqlite3_stmt *pStmt = 0; + if( p->errCode==SQLITE_OK ){ + va_list ap; + char *z; + va_start(ap, zFmt); + z = sqlite3_vmprintf(zFmt, ap); + va_end(ap); + if( z==0 ){ + p->errCode = SQLITE_NOMEM; + }else{ + pStmt = recoverPrepare(p, db, z); + sqlite3_free(z); + } + } + return pStmt; +} + +/* +** Reset SQLite statement handle pStmt. If the call to sqlite3_reset() +** indicates that an error occurred, and there is not already an error +** in the recover handle passed as the first argument, set the error +** code and error message appropriately. +** +** This function returns a copy of the statement handle pointer passed +** as the second argument. +*/ +static sqlite3_stmt *recoverReset(sqlite3_recover *p, sqlite3_stmt *pStmt){ + int rc = sqlite3_reset(pStmt); + if( rc!=SQLITE_OK && rc!=SQLITE_CONSTRAINT && p->errCode==SQLITE_OK ){ + recoverDbError(p, sqlite3_db_handle(pStmt)); + } + return pStmt; +} + +/* +** Finalize SQLite statement handle pStmt. If the call to sqlite3_reset() +** indicates that an error occurred, and there is not already an error +** in the recover handle passed as the first argument, set the error +** code and error message appropriately. +*/ +static void recoverFinalize(sqlite3_recover *p, sqlite3_stmt *pStmt){ + sqlite3 *db = sqlite3_db_handle(pStmt); + int rc = sqlite3_finalize(pStmt); + if( rc!=SQLITE_OK && p->errCode==SQLITE_OK ){ + recoverDbError(p, db); + } +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). A copy of p->errCode is returned in this +** case. +** +** Otherwise, execute SQL script zSql. If successful, return SQLITE_OK. +** Or, if an error occurs, leave an error code and message in the recover +** handle and return a copy of the error code. +*/ +static int recoverExec(sqlite3_recover *p, sqlite3 *db, const char *zSql){ + if( p->errCode==SQLITE_OK ){ + int rc = sqlite3_exec(db, zSql, 0, 0, 0); + if( rc ){ + recoverDbError(p, db); + } + } + return p->errCode; +} + +/* +** Bind the value pVal to parameter iBind of statement pStmt. Leave an +** error in the recover handle passed as the first argument if an error +** (e.g. an OOM) occurs. +*/ +static void recoverBindValue( + sqlite3_recover *p, + sqlite3_stmt *pStmt, + int iBind, + sqlite3_value *pVal +){ + if( p->errCode==SQLITE_OK ){ + int rc = sqlite3_bind_value(pStmt, iBind, pVal); + if( rc ) recoverError(p, rc, 0); + } +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). NULL is returned in this case. +** +** Otherwise, an attempt is made to interpret zFmt as a printf() style +** formatting string and the result of using the trailing arguments for +** parameter substitution with it written into a buffer obtained from +** sqlite3_malloc(). If successful, a pointer to the buffer is returned. +** It is the responsibility of the caller to eventually free the buffer +** using sqlite3_free(). +** +** Or, if an error occurs, an error code and message is left in the recover +** handle and NULL returned. +*/ +static char *recoverMPrintf(sqlite3_recover *p, const char *zFmt, ...){ + va_list ap; + char *z; + va_start(ap, zFmt); + z = sqlite3_vmprintf(zFmt, ap); + va_end(ap); + if( p->errCode==SQLITE_OK ){ + if( z==0 ) p->errCode = SQLITE_NOMEM; + }else{ + sqlite3_free(z); + z = 0; + } + return z; +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). Zero is returned in this case. +** +** Otherwise, execute "PRAGMA page_count" against the input database. If +** successful, return the integer result. Or, if an error occurs, leave an +** error code and error message in the sqlite3_recover handle and return +** zero. +*/ +static i64 recoverPageCount(sqlite3_recover *p){ + i64 nPg = 0; + if( p->errCode==SQLITE_OK ){ + sqlite3_stmt *pStmt = 0; + pStmt = recoverPreparePrintf(p, p->dbIn, "PRAGMA %Q.page_count", p->zDb); + if( pStmt ){ + sqlite3_step(pStmt); + nPg = sqlite3_column_int64(pStmt, 0); + } + recoverFinalize(p, pStmt); + } + return nPg; +} + +/* +** Implementation of SQL scalar function "read_i32". The first argument to +** this function must be a blob. The second a non-negative integer. This +** function reads and returns a 32-bit big-endian integer from byte +** offset (4*<arg2>) of the blob. +** +** SELECT read_i32(<blob>, <idx>) +*/ +static void recoverReadI32( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + const unsigned char *pBlob; + int nBlob; + int iInt; + + assert( argc==2 ); + nBlob = sqlite3_value_bytes(argv[0]); + pBlob = (const unsigned char*)sqlite3_value_blob(argv[0]); + iInt = sqlite3_value_int(argv[1]) & 0xFFFF; + + if( (iInt+1)*4<=nBlob ){ + const unsigned char *a = &pBlob[iInt*4]; + i64 iVal = ((i64)a[0]<<24) + + ((i64)a[1]<<16) + + ((i64)a[2]<< 8) + + ((i64)a[3]<< 0); + sqlite3_result_int64(context, iVal); + } +} + +/* +** Implementation of SQL scalar function "page_is_used". This function +** is used as part of the procedure for locating orphan rows for the +** lost-and-found table, and it depends on those routines having populated +** the sqlite3_recover.laf.pUsed variable. +** +** The only argument to this function is a page-number. It returns true +** if the page has already been used somehow during data recovery, or false +** otherwise. +** +** SELECT page_is_used(<pgno>); +*/ +static void recoverPageIsUsed( + sqlite3_context *pCtx, + int nArg, + sqlite3_value **apArg +){ + sqlite3_recover *p = (sqlite3_recover*)sqlite3_user_data(pCtx); + i64 pgno = sqlite3_value_int64(apArg[0]); + assert( nArg==1 ); + sqlite3_result_int(pCtx, recoverBitmapQuery(p->laf.pUsed, pgno)); +} + +/* +** The implementation of a user-defined SQL function invoked by the +** sqlite_dbdata and sqlite_dbptr virtual table modules to access pages +** of the database being recovered. +** +** This function always takes a single integer argument. If the argument +** is zero, then the value returned is the number of pages in the db being +** recovered. If the argument is greater than zero, it is a page number. +** The value returned in this case is an SQL blob containing the data for +** the identified page of the db being recovered. e.g. +** +** SELECT getpage(0); -- return number of pages in db +** SELECT getpage(4); -- return page 4 of db as a blob of data +*/ +static void recoverGetPage( + sqlite3_context *pCtx, + int nArg, + sqlite3_value **apArg +){ + sqlite3_recover *p = (sqlite3_recover*)sqlite3_user_data(pCtx); + i64 pgno = sqlite3_value_int64(apArg[0]); + sqlite3_stmt *pStmt = 0; + + assert( nArg==1 ); + if( pgno==0 ){ + i64 nPg = recoverPageCount(p); + sqlite3_result_int64(pCtx, nPg); + return; + }else{ + if( p->pGetPage==0 ){ + pStmt = p->pGetPage = recoverPreparePrintf( + p, p->dbIn, "SELECT data FROM sqlite_dbpage(%Q) WHERE pgno=?", p->zDb + ); + }else if( p->errCode==SQLITE_OK ){ + pStmt = p->pGetPage; + } + + if( pStmt ){ + sqlite3_bind_int64(pStmt, 1, pgno); + if( SQLITE_ROW==sqlite3_step(pStmt) ){ + const u8 *aPg; + int nPg; + assert( p->errCode==SQLITE_OK ); + aPg = sqlite3_column_blob(pStmt, 0); + nPg = sqlite3_column_bytes(pStmt, 0); + if( pgno==1 && nPg==p->pgsz && 0==memcmp(p->pPage1Cache, aPg, nPg) ){ + aPg = p->pPage1Disk; + } + sqlite3_result_blob(pCtx, aPg, nPg-p->nReserve, SQLITE_TRANSIENT); + } + recoverReset(p, pStmt); + } + } + + if( p->errCode ){ + if( p->zErrMsg ) sqlite3_result_error(pCtx, p->zErrMsg, -1); + sqlite3_result_error_code(pCtx, p->errCode); + } +} + +/* +** Find a string that is not found anywhere in z[]. Return a pointer +** to that string. +** +** Try to use zA and zB first. If both of those are already found in z[] +** then make up some string and store it in the buffer zBuf. +*/ +static const char *recoverUnusedString( + const char *z, /* Result must not appear anywhere in z */ + const char *zA, const char *zB, /* Try these first */ + char *zBuf /* Space to store a generated string */ +){ + unsigned i = 0; + if( strstr(z, zA)==0 ) return zA; + if( strstr(z, zB)==0 ) return zB; + do{ + sqlite3_snprintf(20,zBuf,"(%s%u)", zA, i++); + }while( strstr(z,zBuf)!=0 ); + return zBuf; +} + +/* +** Implementation of scalar SQL function "escape_crnl". The argument passed to +** this function is the output of built-in function quote(). If the first +** character of the input is "'", indicating that the value passed to quote() +** was a text value, then this function searches the input for "\n" and "\r" +** characters and adds a wrapper similar to the following: +** +** replace(replace(<input>, '\n', char(10), '\r', char(13)); +** +** Or, if the first character of the input is not "'", then a copy of the input +** is returned. +*/ +static void recoverEscapeCrnl( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + const char *zText = (const char*)sqlite3_value_text(argv[0]); + (void)argc; + if( zText && zText[0]=='\'' ){ + int nText = sqlite3_value_bytes(argv[0]); + int i; + char zBuf1[20]; + char zBuf2[20]; + const char *zNL = 0; + const char *zCR = 0; + int nCR = 0; + int nNL = 0; + + for(i=0; zText[i]; i++){ + if( zNL==0 && zText[i]=='\n' ){ + zNL = recoverUnusedString(zText, "\\n", "\\012", zBuf1); + nNL = (int)strlen(zNL); + } + if( zCR==0 && zText[i]=='\r' ){ + zCR = recoverUnusedString(zText, "\\r", "\\015", zBuf2); + nCR = (int)strlen(zCR); + } + } + + if( zNL || zCR ){ + int iOut = 0; + i64 nMax = (nNL > nCR) ? nNL : nCR; + i64 nAlloc = nMax * nText + (nMax+64)*2; + char *zOut = (char*)sqlite3_malloc64(nAlloc); + if( zOut==0 ){ + sqlite3_result_error_nomem(context); + return; + } + + if( zNL && zCR ){ + memcpy(&zOut[iOut], "replace(replace(", 16); + iOut += 16; + }else{ + memcpy(&zOut[iOut], "replace(", 8); + iOut += 8; + } + for(i=0; zText[i]; i++){ + if( zText[i]=='\n' ){ + memcpy(&zOut[iOut], zNL, nNL); + iOut += nNL; + }else if( zText[i]=='\r' ){ + memcpy(&zOut[iOut], zCR, nCR); + iOut += nCR; + }else{ + zOut[iOut] = zText[i]; + iOut++; + } + } + + if( zNL ){ + memcpy(&zOut[iOut], ",'", 2); iOut += 2; + memcpy(&zOut[iOut], zNL, nNL); iOut += nNL; + memcpy(&zOut[iOut], "', char(10))", 12); iOut += 12; + } + if( zCR ){ + memcpy(&zOut[iOut], ",'", 2); iOut += 2; + memcpy(&zOut[iOut], zCR, nCR); iOut += nCR; + memcpy(&zOut[iOut], "', char(13))", 12); iOut += 12; + } + + sqlite3_result_text(context, zOut, iOut, SQLITE_TRANSIENT); + sqlite3_free(zOut); + return; + } + } + + sqlite3_result_value(context, argv[0]); +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). A copy of the error code is returned in +** this case. +** +** Otherwise, attempt to populate temporary table "recovery.schema" with the +** parts of the database schema that can be extracted from the input database. +** +** If no error occurs, SQLITE_OK is returned. Otherwise, an error code +** and error message are left in the recover handle and a copy of the +** error code returned. It is not considered an error if part of all of +** the database schema cannot be recovered due to corruption. +*/ +static int recoverCacheSchema(sqlite3_recover *p){ + return recoverExec(p, p->dbOut, + "WITH RECURSIVE pages(p) AS (" + " SELECT 1" + " UNION" + " SELECT child FROM sqlite_dbptr('getpage()'), pages WHERE pgno=p" + ")" + "INSERT INTO recovery.schema SELECT" + " max(CASE WHEN field=0 THEN value ELSE NULL END)," + " max(CASE WHEN field=1 THEN value ELSE NULL END)," + " max(CASE WHEN field=2 THEN value ELSE NULL END)," + " max(CASE WHEN field=3 THEN value ELSE NULL END)," + " max(CASE WHEN field=4 THEN value ELSE NULL END)" + "FROM sqlite_dbdata('getpage()') WHERE pgno IN (" + " SELECT p FROM pages" + ") GROUP BY pgno, cell" + ); +} + +/* +** If this recover handle is not in SQL callback mode (i.e. was not created +** using sqlite3_recover_init_sql()) of if an error has already occurred, +** this function is a no-op. Otherwise, issue a callback with SQL statement +** zSql as the parameter. +** +** If the callback returns non-zero, set the recover handle error code to +** the value returned (so that the caller will abandon processing). +*/ +static void recoverSqlCallback(sqlite3_recover *p, const char *zSql){ + if( p->errCode==SQLITE_OK && p->xSql ){ + int res = p->xSql(p->pSqlCtx, zSql); + if( res ){ + recoverError(p, SQLITE_ERROR, "callback returned an error - %d", res); + } + } +} + +/* +** Transfer the following settings from the input database to the output +** database: +** +** + page-size, +** + auto-vacuum settings, +** + database encoding, +** + user-version (PRAGMA user_version), and +** + application-id (PRAGMA application_id), and +*/ +static void recoverTransferSettings(sqlite3_recover *p){ + const char *aPragma[] = { + "encoding", + "page_size", + "auto_vacuum", + "user_version", + "application_id" + }; + int ii; + + /* Truncate the output database to 0 pages in size. This is done by + ** opening a new, empty, temp db, then using the backup API to clobber + ** any existing output db with a copy of it. */ + if( p->errCode==SQLITE_OK ){ + sqlite3 *db2 = 0; + int rc = sqlite3_open("", &db2); + if( rc!=SQLITE_OK ){ + recoverDbError(p, db2); + return; + } + + for(ii=0; ii<(int)(sizeof(aPragma)/sizeof(aPragma[0])); ii++){ + const char *zPrag = aPragma[ii]; + sqlite3_stmt *p1 = 0; + p1 = recoverPreparePrintf(p, p->dbIn, "PRAGMA %Q.%s", p->zDb, zPrag); + if( p->errCode==SQLITE_OK && sqlite3_step(p1)==SQLITE_ROW ){ + const char *zArg = (const char*)sqlite3_column_text(p1, 0); + char *z2 = recoverMPrintf(p, "PRAGMA %s = %Q", zPrag, zArg); + recoverSqlCallback(p, z2); + recoverExec(p, db2, z2); + sqlite3_free(z2); + if( zArg==0 ){ + recoverError(p, SQLITE_NOMEM, 0); + } + } + recoverFinalize(p, p1); + } + recoverExec(p, db2, "CREATE TABLE t1(a); DROP TABLE t1;"); + + if( p->errCode==SQLITE_OK ){ + sqlite3 *db = p->dbOut; + sqlite3_backup *pBackup = sqlite3_backup_init(db, "main", db2, "main"); + if( pBackup ){ + sqlite3_backup_step(pBackup, -1); + p->errCode = sqlite3_backup_finish(pBackup); + }else{ + recoverDbError(p, db); + } + } + + sqlite3_close(db2); + } +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). A copy of the error code is returned in +** this case. +** +** Otherwise, an attempt is made to open the output database, attach +** and create the schema of the temporary database used to store +** intermediate data, and to register all required user functions and +** virtual table modules with the output handle. +** +** If no error occurs, SQLITE_OK is returned. Otherwise, an error code +** and error message are left in the recover handle and a copy of the +** error code returned. +*/ +static int recoverOpenOutput(sqlite3_recover *p){ + struct Func { + const char *zName; + int nArg; + void (*xFunc)(sqlite3_context*,int,sqlite3_value **); + } aFunc[] = { + { "getpage", 1, recoverGetPage }, + { "page_is_used", 1, recoverPageIsUsed }, + { "read_i32", 2, recoverReadI32 }, + { "escape_crnl", 1, recoverEscapeCrnl }, + }; + + const int flags = SQLITE_OPEN_URI|SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE; + sqlite3 *db = 0; /* New database handle */ + int ii; /* For iterating through aFunc[] */ + + assert( p->dbOut==0 ); + + if( sqlite3_open_v2(p->zUri, &db, flags, 0) ){ + recoverDbError(p, db); + } + + /* Register the sqlite_dbdata and sqlite_dbptr virtual table modules. + ** These two are registered with the output database handle - this + ** module depends on the input handle supporting the sqlite_dbpage + ** virtual table only. */ + if( p->errCode==SQLITE_OK ){ + p->errCode = sqlite3_dbdata_init(db, 0, 0); + } + + /* Register the custom user-functions with the output handle. */ + for(ii=0; + p->errCode==SQLITE_OK && ii<(int)(sizeof(aFunc)/sizeof(aFunc[0])); + ii++){ + p->errCode = sqlite3_create_function(db, aFunc[ii].zName, + aFunc[ii].nArg, SQLITE_UTF8, (void*)p, aFunc[ii].xFunc, 0, 0 + ); + } + + p->dbOut = db; + return p->errCode; +} + +/* +** Attach the auxiliary database 'recovery' to the output database handle. +** This temporary database is used during the recovery process and then +** discarded. +*/ +static void recoverOpenRecovery(sqlite3_recover *p){ + char *zSql = recoverMPrintf(p, "ATTACH %Q AS recovery;", p->zStateDb); + recoverExec(p, p->dbOut, zSql); + recoverExec(p, p->dbOut, + "PRAGMA writable_schema = 1;" + "CREATE TABLE recovery.map(pgno INTEGER PRIMARY KEY, parent INT);" + "CREATE TABLE recovery.schema(type, name, tbl_name, rootpage, sql);" + ); + sqlite3_free(zSql); +} + + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). +** +** Otherwise, argument zName must be the name of a table that has just been +** created in the output database. This function queries the output db +** for the schema of said table, and creates a RecoverTable object to +** store the schema in memory. The new RecoverTable object is linked into +** the list at sqlite3_recover.pTblList. +** +** Parameter iRoot must be the root page of table zName in the INPUT +** database. +*/ +static void recoverAddTable( + sqlite3_recover *p, + const char *zName, /* Name of table created in output db */ + i64 iRoot /* Root page of same table in INPUT db */ +){ + sqlite3_stmt *pStmt = recoverPreparePrintf(p, p->dbOut, + "PRAGMA table_xinfo(%Q)", zName + ); + + if( pStmt ){ + int iPk = -1; + int iBind = 1; + RecoverTable *pNew = 0; + int nCol = 0; + int nName = recoverStrlen(zName); + int nByte = 0; + while( sqlite3_step(pStmt)==SQLITE_ROW ){ + nCol++; + nByte += (sqlite3_column_bytes(pStmt, 1)+1); + } + nByte += sizeof(RecoverTable) + nCol*sizeof(RecoverColumn) + nName+1; + recoverReset(p, pStmt); + + pNew = recoverMalloc(p, nByte); + if( pNew ){ + int i = 0; + int iField = 0; + char *csr = 0; + pNew->aCol = (RecoverColumn*)&pNew[1]; + pNew->zTab = csr = (char*)&pNew->aCol[nCol]; + pNew->nCol = nCol; + pNew->iRoot = iRoot; + memcpy(csr, zName, nName); + csr += nName+1; + + for(i=0; sqlite3_step(pStmt)==SQLITE_ROW; i++){ + int iPKF = sqlite3_column_int(pStmt, 5); + int n = sqlite3_column_bytes(pStmt, 1); + const char *z = (const char*)sqlite3_column_text(pStmt, 1); + const char *zType = (const char*)sqlite3_column_text(pStmt, 2); + int eHidden = sqlite3_column_int(pStmt, 6); + + if( iPk==-1 && iPKF==1 && !sqlite3_stricmp("integer", zType) ) iPk = i; + if( iPKF>1 ) iPk = -2; + pNew->aCol[i].zCol = csr; + pNew->aCol[i].eHidden = eHidden; + if( eHidden==RECOVER_EHIDDEN_VIRTUAL ){ + pNew->aCol[i].iField = -1; + }else{ + pNew->aCol[i].iField = iField++; + } + if( eHidden!=RECOVER_EHIDDEN_VIRTUAL + && eHidden!=RECOVER_EHIDDEN_STORED + ){ + pNew->aCol[i].iBind = iBind++; + } + memcpy(csr, z, n); + csr += (n+1); + } + + pNew->pNext = p->pTblList; + p->pTblList = pNew; + pNew->bIntkey = 1; + } + + recoverFinalize(p, pStmt); + + pStmt = recoverPreparePrintf(p, p->dbOut, "PRAGMA index_xinfo(%Q)", zName); + while( pStmt && sqlite3_step(pStmt)==SQLITE_ROW ){ + int iField = sqlite3_column_int(pStmt, 0); + int iCol = sqlite3_column_int(pStmt, 1); + + assert( iCol<pNew->nCol ); + pNew->aCol[iCol].iField = iField; + + pNew->bIntkey = 0; + iPk = -2; + } + recoverFinalize(p, pStmt); + + if( p->errCode==SQLITE_OK ){ + if( iPk>=0 ){ + pNew->aCol[iPk].bIPK = 1; + }else if( pNew->bIntkey ){ + pNew->iRowidBind = iBind++; + } + } + } +} + +/* +** This function is called after recoverCacheSchema() has cached those parts +** of the input database schema that could be recovered in temporary table +** "recovery.schema". This function creates in the output database copies +** of all parts of that schema that must be created before the tables can +** be populated. Specifically, this means: +** +** * all tables that are not VIRTUAL, and +** * UNIQUE indexes. +** +** If the recovery handle uses SQL callbacks, then callbacks containing +** the associated "CREATE TABLE" and "CREATE INDEX" statements are made. +** +** Additionally, records are added to the sqlite_schema table of the +** output database for any VIRTUAL tables. The CREATE VIRTUAL TABLE +** records are written directly to sqlite_schema, not actually executed. +** If the handle is in SQL callback mode, then callbacks are invoked +** with equivalent SQL statements. +*/ +static int recoverWriteSchema1(sqlite3_recover *p){ + sqlite3_stmt *pSelect = 0; + sqlite3_stmt *pTblname = 0; + + pSelect = recoverPrepare(p, p->dbOut, + "WITH dbschema(rootpage, name, sql, tbl, isVirtual, isIndex) AS (" + " SELECT rootpage, name, sql, " + " type='table', " + " sql LIKE 'create virtual%'," + " (type='index' AND (sql LIKE '%unique%' OR ?1))" + " FROM recovery.schema" + ")" + "SELECT rootpage, tbl, isVirtual, name, sql" + " FROM dbschema " + " WHERE tbl OR isIndex" + " ORDER BY tbl DESC, name=='sqlite_sequence' DESC" + ); + + pTblname = recoverPrepare(p, p->dbOut, + "SELECT name FROM sqlite_schema " + "WHERE type='table' ORDER BY rowid DESC LIMIT 1" + ); + + if( pSelect ){ + sqlite3_bind_int(pSelect, 1, p->bSlowIndexes); + while( sqlite3_step(pSelect)==SQLITE_ROW ){ + i64 iRoot = sqlite3_column_int64(pSelect, 0); + int bTable = sqlite3_column_int(pSelect, 1); + int bVirtual = sqlite3_column_int(pSelect, 2); + const char *zName = (const char*)sqlite3_column_text(pSelect, 3); + const char *zSql = (const char*)sqlite3_column_text(pSelect, 4); + char *zFree = 0; + int rc = SQLITE_OK; + + if( bVirtual ){ + zSql = (const char*)(zFree = recoverMPrintf(p, + "INSERT INTO sqlite_schema VALUES('table', %Q, %Q, 0, %Q)", + zName, zName, zSql + )); + } + rc = sqlite3_exec(p->dbOut, zSql, 0, 0, 0); + if( rc==SQLITE_OK ){ + recoverSqlCallback(p, zSql); + if( bTable && !bVirtual ){ + if( SQLITE_ROW==sqlite3_step(pTblname) ){ + const char *zTbl = (const char*)sqlite3_column_text(pTblname, 0); + recoverAddTable(p, zTbl, iRoot); + } + recoverReset(p, pTblname); + } + }else if( rc!=SQLITE_ERROR ){ + recoverDbError(p, p->dbOut); + } + sqlite3_free(zFree); + } + } + recoverFinalize(p, pSelect); + recoverFinalize(p, pTblname); + + return p->errCode; +} + +/* +** This function is called after the output database has been populated. It +** adds all recovered schema elements that were not created in the output +** database by recoverWriteSchema1() - everything except for tables and +** UNIQUE indexes. Specifically: +** +** * views, +** * triggers, +** * non-UNIQUE indexes. +** +** If the recover handle is in SQL callback mode, then equivalent callbacks +** are issued to create the schema elements. +*/ +static int recoverWriteSchema2(sqlite3_recover *p){ + sqlite3_stmt *pSelect = 0; + + pSelect = recoverPrepare(p, p->dbOut, + p->bSlowIndexes ? + "SELECT rootpage, sql FROM recovery.schema " + " WHERE type!='table' AND type!='index'" + : + "SELECT rootpage, sql FROM recovery.schema " + " WHERE type!='table' AND (type!='index' OR sql NOT LIKE '%unique%')" + ); + + if( pSelect ){ + while( sqlite3_step(pSelect)==SQLITE_ROW ){ + const char *zSql = (const char*)sqlite3_column_text(pSelect, 1); + int rc = sqlite3_exec(p->dbOut, zSql, 0, 0, 0); + if( rc==SQLITE_OK ){ + recoverSqlCallback(p, zSql); + }else if( rc!=SQLITE_ERROR ){ + recoverDbError(p, p->dbOut); + } + } + } + recoverFinalize(p, pSelect); + + return p->errCode; +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). In this case it returns NULL. +** +** Otherwise, if the recover handle is configured to create an output +** database (was created by sqlite3_recover_init()), then this function +** prepares and returns an SQL statement to INSERT a new record into table +** pTab, assuming the first nField fields of a record extracted from disk +** are valid. +** +** For example, if table pTab is: +** +** CREATE TABLE name(a, b GENERATED ALWAYS AS (a+1) STORED, c, d, e); +** +** And nField is 4, then the SQL statement prepared and returned is: +** +** INSERT INTO (a, c, d) VALUES (?1, ?2, ?3); +** +** In this case even though 4 values were extracted from the input db, +** only 3 are written to the output, as the generated STORED column +** cannot be written. +** +** If the recover handle is in SQL callback mode, then the SQL statement +** prepared is such that evaluating it returns a single row containing +** a single text value - itself an SQL statement similar to the above, +** except with SQL literals in place of the variables. For example: +** +** SELECT 'INSERT INTO (a, c, d) VALUES (' +** || quote(?1) || ', ' +** || quote(?2) || ', ' +** || quote(?3) || ')'; +** +** In either case, it is the responsibility of the caller to eventually +** free the statement handle using sqlite3_finalize(). +*/ +static sqlite3_stmt *recoverInsertStmt( + sqlite3_recover *p, + RecoverTable *pTab, + int nField +){ + sqlite3_stmt *pRet = 0; + const char *zSep = ""; + const char *zSqlSep = ""; + char *zSql = 0; + char *zFinal = 0; + char *zBind = 0; + int ii; + int bSql = p->xSql ? 1 : 0; + + if( nField<=0 ) return 0; + + assert( nField<=pTab->nCol ); + + zSql = recoverMPrintf(p, "INSERT OR IGNORE INTO %Q(", pTab->zTab); + + if( pTab->iRowidBind ){ + assert( pTab->bIntkey ); + zSql = recoverMPrintf(p, "%z_rowid_", zSql); + if( bSql ){ + zBind = recoverMPrintf(p, "%zquote(?%d)", zBind, pTab->iRowidBind); + }else{ + zBind = recoverMPrintf(p, "%z?%d", zBind, pTab->iRowidBind); + } + zSqlSep = "||', '||"; + zSep = ", "; + } + + for(ii=0; ii<nField; ii++){ + int eHidden = pTab->aCol[ii].eHidden; + if( eHidden!=RECOVER_EHIDDEN_VIRTUAL + && eHidden!=RECOVER_EHIDDEN_STORED + ){ + assert( pTab->aCol[ii].iField>=0 && pTab->aCol[ii].iBind>=1 ); + zSql = recoverMPrintf(p, "%z%s%Q", zSql, zSep, pTab->aCol[ii].zCol); + + if( bSql ){ + zBind = recoverMPrintf(p, + "%z%sescape_crnl(quote(?%d))", zBind, zSqlSep, pTab->aCol[ii].iBind + ); + zSqlSep = "||', '||"; + }else{ + zBind = recoverMPrintf(p, "%z%s?%d", zBind, zSep, pTab->aCol[ii].iBind); + } + zSep = ", "; + } + } + + if( bSql ){ + zFinal = recoverMPrintf(p, "SELECT %Q || ') VALUES (' || %s || ')'", + zSql, zBind + ); + }else{ + zFinal = recoverMPrintf(p, "%s) VALUES (%s)", zSql, zBind); + } + + pRet = recoverPrepare(p, p->dbOut, zFinal); + sqlite3_free(zSql); + sqlite3_free(zBind); + sqlite3_free(zFinal); + + return pRet; +} + + +/* +** Search the list of RecoverTable objects at p->pTblList for one that +** has root page iRoot in the input database. If such an object is found, +** return a pointer to it. Otherwise, return NULL. +*/ +static RecoverTable *recoverFindTable(sqlite3_recover *p, u32 iRoot){ + RecoverTable *pRet = 0; + for(pRet=p->pTblList; pRet && pRet->iRoot!=iRoot; pRet=pRet->pNext); + return pRet; +} + +/* +** This function attempts to create a lost and found table within the +** output db. If successful, it returns a pointer to a buffer containing +** the name of the new table. It is the responsibility of the caller to +** eventually free this buffer using sqlite3_free(). +** +** If an error occurs, NULL is returned and an error code and error +** message left in the recover handle. +*/ +static char *recoverLostAndFoundCreate( + sqlite3_recover *p, /* Recover object */ + int nField /* Number of column fields in new table */ +){ + char *zTbl = 0; + sqlite3_stmt *pProbe = 0; + int ii = 0; + + pProbe = recoverPrepare(p, p->dbOut, + "SELECT 1 FROM sqlite_schema WHERE name=?" + ); + for(ii=-1; zTbl==0 && p->errCode==SQLITE_OK && ii<1000; ii++){ + int bFail = 0; + if( ii<0 ){ + zTbl = recoverMPrintf(p, "%s", p->zLostAndFound); + }else{ + zTbl = recoverMPrintf(p, "%s_%d", p->zLostAndFound, ii); + } + + if( p->errCode==SQLITE_OK ){ + sqlite3_bind_text(pProbe, 1, zTbl, -1, SQLITE_STATIC); + if( SQLITE_ROW==sqlite3_step(pProbe) ){ + bFail = 1; + } + recoverReset(p, pProbe); + } + + if( bFail ){ + sqlite3_clear_bindings(pProbe); + sqlite3_free(zTbl); + zTbl = 0; + } + } + recoverFinalize(p, pProbe); + + if( zTbl ){ + const char *zSep = 0; + char *zField = 0; + char *zSql = 0; + + zSep = "rootpgno INTEGER, pgno INTEGER, nfield INTEGER, id INTEGER, "; + for(ii=0; p->errCode==SQLITE_OK && ii<nField; ii++){ + zField = recoverMPrintf(p, "%z%sc%d", zField, zSep, ii); + zSep = ", "; + } + + zSql = recoverMPrintf(p, "CREATE TABLE %s(%s)", zTbl, zField); + sqlite3_free(zField); + + recoverExec(p, p->dbOut, zSql); + recoverSqlCallback(p, zSql); + sqlite3_free(zSql); + }else if( p->errCode==SQLITE_OK ){ + recoverError( + p, SQLITE_ERROR, "failed to create %s output table", p->zLostAndFound + ); + } + + return zTbl; +} + +/* +** Synthesize and prepare an INSERT statement to write to the lost_and_found +** table in the output database. The name of the table is zTab, and it has +** nField c* fields. +*/ +static sqlite3_stmt *recoverLostAndFoundInsert( + sqlite3_recover *p, + const char *zTab, + int nField +){ + int nTotal = nField + 4; + int ii; + char *zBind = 0; + sqlite3_stmt *pRet = 0; + + if( p->xSql==0 ){ + for(ii=0; ii<nTotal; ii++){ + zBind = recoverMPrintf(p, "%z%s?", zBind, zBind?", ":"", ii); + } + pRet = recoverPreparePrintf( + p, p->dbOut, "INSERT INTO %s VALUES(%s)", zTab, zBind + ); + }else{ + const char *zSep = ""; + for(ii=0; ii<nTotal; ii++){ + zBind = recoverMPrintf(p, "%z%squote(?)", zBind, zSep); + zSep = "|| ', ' ||"; + } + pRet = recoverPreparePrintf( + p, p->dbOut, "SELECT 'INSERT INTO %s VALUES(' || %s || ')'", zTab, zBind + ); + } + + sqlite3_free(zBind); + return pRet; +} + +/* +** Input database page iPg contains data that will be written to the +** lost-and-found table of the output database. This function attempts +** to identify the root page of the tree that page iPg belonged to. +** If successful, it sets output variable (*piRoot) to the page number +** of the root page and returns SQLITE_OK. Otherwise, if an error occurs, +** an SQLite error code is returned and the final value of *piRoot +** undefined. +*/ +static int recoverLostAndFoundFindRoot( + sqlite3_recover *p, + i64 iPg, + i64 *piRoot +){ + RecoverStateLAF *pLaf = &p->laf; + + if( pLaf->pFindRoot==0 ){ + pLaf->pFindRoot = recoverPrepare(p, p->dbOut, + "WITH RECURSIVE p(pgno) AS (" + " SELECT ?" + " UNION" + " SELECT parent FROM recovery.map AS m, p WHERE m.pgno=p.pgno" + ") " + "SELECT p.pgno FROM p, recovery.map m WHERE m.pgno=p.pgno " + " AND m.parent IS NULL" + ); + } + if( p->errCode==SQLITE_OK ){ + sqlite3_bind_int64(pLaf->pFindRoot, 1, iPg); + if( sqlite3_step(pLaf->pFindRoot)==SQLITE_ROW ){ + *piRoot = sqlite3_column_int64(pLaf->pFindRoot, 0); + }else{ + *piRoot = iPg; + } + recoverReset(p, pLaf->pFindRoot); + } + return p->errCode; +} + +/* +** Recover data from page iPage of the input database and write it to +** the lost-and-found table in the output database. +*/ +static void recoverLostAndFoundOnePage(sqlite3_recover *p, i64 iPage){ + RecoverStateLAF *pLaf = &p->laf; + sqlite3_value **apVal = pLaf->apVal; + sqlite3_stmt *pPageData = pLaf->pPageData; + sqlite3_stmt *pInsert = pLaf->pInsert; + + int nVal = -1; + int iPrevCell = 0; + i64 iRoot = 0; + int bHaveRowid = 0; + i64 iRowid = 0; + int ii = 0; + + if( recoverLostAndFoundFindRoot(p, iPage, &iRoot) ) return; + sqlite3_bind_int64(pPageData, 1, iPage); + while( p->errCode==SQLITE_OK && SQLITE_ROW==sqlite3_step(pPageData) ){ + int iCell = sqlite3_column_int64(pPageData, 0); + int iField = sqlite3_column_int64(pPageData, 1); + + if( iPrevCell!=iCell && nVal>=0 ){ + /* Insert the new row */ + sqlite3_bind_int64(pInsert, 1, iRoot); /* rootpgno */ + sqlite3_bind_int64(pInsert, 2, iPage); /* pgno */ + sqlite3_bind_int(pInsert, 3, nVal); /* nfield */ + if( bHaveRowid ){ + sqlite3_bind_int64(pInsert, 4, iRowid); /* id */ + } + for(ii=0; ii<nVal; ii++){ + recoverBindValue(p, pInsert, 5+ii, apVal[ii]); + } + if( sqlite3_step(pInsert)==SQLITE_ROW ){ + recoverSqlCallback(p, (const char*)sqlite3_column_text(pInsert, 0)); + } + recoverReset(p, pInsert); + + /* Discard the accumulated row data */ + for(ii=0; ii<nVal; ii++){ + sqlite3_value_free(apVal[ii]); + apVal[ii] = 0; + } + sqlite3_clear_bindings(pInsert); + bHaveRowid = 0; + nVal = -1; + } + + if( iCell<0 ) break; + + if( iField<0 ){ + assert( nVal==-1 ); + iRowid = sqlite3_column_int64(pPageData, 2); + bHaveRowid = 1; + nVal = 0; + }else if( iField<pLaf->nMaxField ){ + sqlite3_value *pVal = sqlite3_column_value(pPageData, 2); + apVal[iField] = sqlite3_value_dup(pVal); + assert( iField==nVal || (nVal==-1 && iField==0) ); + nVal = iField+1; + if( apVal[iField]==0 ){ + recoverError(p, SQLITE_NOMEM, 0); + } + } + + iPrevCell = iCell; + } + recoverReset(p, pPageData); + + for(ii=0; ii<nVal; ii++){ + sqlite3_value_free(apVal[ii]); + apVal[ii] = 0; + } +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_LOSTANDFOUND3 state - during which the lost-and-found +** table of the output database is populated with recovered data that can +** not be assigned to any recovered schema object. +*/ +static int recoverLostAndFound3Step(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + if( p->errCode==SQLITE_OK ){ + if( pLaf->pInsert==0 ){ + return SQLITE_DONE; + }else{ + if( p->errCode==SQLITE_OK ){ + int res = sqlite3_step(pLaf->pAllPage); + if( res==SQLITE_ROW ){ + i64 iPage = sqlite3_column_int64(pLaf->pAllPage, 0); + if( recoverBitmapQuery(pLaf->pUsed, iPage)==0 ){ + recoverLostAndFoundOnePage(p, iPage); + } + }else{ + recoverReset(p, pLaf->pAllPage); + return SQLITE_DONE; + } + } + } + } + return SQLITE_OK; +} + +/* +** Initialize resources required in RECOVER_STATE_LOSTANDFOUND3 +** state - during which the lost-and-found table of the output database +** is populated with recovered data that can not be assigned to any +** recovered schema object. +*/ +static void recoverLostAndFound3Init(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + + if( pLaf->nMaxField>0 ){ + char *zTab = 0; /* Name of lost_and_found table */ + + zTab = recoverLostAndFoundCreate(p, pLaf->nMaxField); + pLaf->pInsert = recoverLostAndFoundInsert(p, zTab, pLaf->nMaxField); + sqlite3_free(zTab); + + pLaf->pAllPage = recoverPreparePrintf(p, p->dbOut, + "WITH RECURSIVE seq(ii) AS (" + " SELECT 1 UNION ALL SELECT ii+1 FROM seq WHERE ii<%lld" + ")" + "SELECT ii FROM seq" , p->laf.nPg + ); + pLaf->pPageData = recoverPrepare(p, p->dbOut, + "SELECT cell, field, value " + "FROM sqlite_dbdata('getpage()') d WHERE d.pgno=? " + "UNION ALL " + "SELECT -1, -1, -1" + ); + + pLaf->apVal = (sqlite3_value**)recoverMalloc(p, + pLaf->nMaxField*sizeof(sqlite3_value*) + ); + } +} + +/* +** Initialize resources required in RECOVER_STATE_WRITING state - during which +** tables recovered from the schema of the input database are populated with +** recovered data. +*/ +static int recoverWriteDataInit(sqlite3_recover *p){ + RecoverStateW1 *p1 = &p->w1; + RecoverTable *pTbl = 0; + int nByte = 0; + + /* Figure out the maximum number of columns for any table in the schema */ + assert( p1->nMax==0 ); + for(pTbl=p->pTblList; pTbl; pTbl=pTbl->pNext){ + if( pTbl->nCol>p1->nMax ) p1->nMax = pTbl->nCol; + } + + /* Allocate an array of (sqlite3_value*) in which to accumulate the values + ** that will be written to the output database in a single row. */ + nByte = sizeof(sqlite3_value*) * (p1->nMax+1); + p1->apVal = (sqlite3_value**)recoverMalloc(p, nByte); + if( p1->apVal==0 ) return p->errCode; + + /* Prepare the SELECT to loop through schema tables (pTbls) and the SELECT + ** to loop through cells that appear to belong to a single table (pSel). */ + p1->pTbls = recoverPrepare(p, p->dbOut, + "SELECT rootpage FROM recovery.schema " + " WHERE type='table' AND (sql NOT LIKE 'create virtual%')" + " ORDER BY (tbl_name='sqlite_sequence') ASC" + ); + p1->pSel = recoverPrepare(p, p->dbOut, + "WITH RECURSIVE pages(page) AS (" + " SELECT ?1" + " UNION" + " SELECT child FROM sqlite_dbptr('getpage()'), pages " + " WHERE pgno=page" + ") " + "SELECT page, cell, field, value " + "FROM sqlite_dbdata('getpage()') d, pages p WHERE p.page=d.pgno " + "UNION ALL " + "SELECT 0, 0, 0, 0" + ); + + return p->errCode; +} + +/* +** Clean up resources allocated by recoverWriteDataInit() (stuff in +** sqlite3_recover.w1). +*/ +static void recoverWriteDataCleanup(sqlite3_recover *p){ + RecoverStateW1 *p1 = &p->w1; + int ii; + for(ii=0; ii<p1->nVal; ii++){ + sqlite3_value_free(p1->apVal[ii]); + } + sqlite3_free(p1->apVal); + recoverFinalize(p, p1->pInsert); + recoverFinalize(p, p1->pTbls); + recoverFinalize(p, p1->pSel); + memset(p1, 0, sizeof(*p1)); +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_WRITING state - during which tables recovered from the +** schema of the input database are populated with recovered data. +*/ +static int recoverWriteDataStep(sqlite3_recover *p){ + RecoverStateW1 *p1 = &p->w1; + sqlite3_stmt *pSel = p1->pSel; + sqlite3_value **apVal = p1->apVal; + + if( p->errCode==SQLITE_OK && p1->pTab==0 ){ + if( sqlite3_step(p1->pTbls)==SQLITE_ROW ){ + i64 iRoot = sqlite3_column_int64(p1->pTbls, 0); + p1->pTab = recoverFindTable(p, iRoot); + + recoverFinalize(p, p1->pInsert); + p1->pInsert = 0; + + /* If this table is unknown, return early. The caller will invoke this + ** function again and it will move on to the next table. */ + if( p1->pTab==0 ) return p->errCode; + + /* If this is the sqlite_sequence table, delete any rows added by + ** earlier INSERT statements on tables with AUTOINCREMENT primary + ** keys before recovering its contents. The p1->pTbls SELECT statement + ** is rigged to deliver "sqlite_sequence" last of all, so we don't + ** worry about it being modified after it is recovered. */ + if( sqlite3_stricmp("sqlite_sequence", p1->pTab->zTab)==0 ){ + recoverExec(p, p->dbOut, "DELETE FROM sqlite_sequence"); + recoverSqlCallback(p, "DELETE FROM sqlite_sequence"); + } + + /* Bind the root page of this table within the original database to + ** SELECT statement p1->pSel. The SELECT statement will then iterate + ** through cells that look like they belong to table pTab. */ + sqlite3_bind_int64(pSel, 1, iRoot); + + p1->nVal = 0; + p1->bHaveRowid = 0; + p1->iPrevPage = -1; + p1->iPrevCell = -1; + }else{ + return SQLITE_DONE; + } + } + assert( p->errCode!=SQLITE_OK || p1->pTab ); + + if( p->errCode==SQLITE_OK && sqlite3_step(pSel)==SQLITE_ROW ){ + RecoverTable *pTab = p1->pTab; + + i64 iPage = sqlite3_column_int64(pSel, 0); + int iCell = sqlite3_column_int(pSel, 1); + int iField = sqlite3_column_int(pSel, 2); + sqlite3_value *pVal = sqlite3_column_value(pSel, 3); + int bNewCell = (p1->iPrevPage!=iPage || p1->iPrevCell!=iCell); + + assert( bNewCell==0 || (iField==-1 || iField==0) ); + assert( bNewCell || iField==p1->nVal || p1->nVal==pTab->nCol ); + + if( bNewCell ){ + int ii = 0; + if( p1->nVal>=0 ){ + if( p1->pInsert==0 || p1->nVal!=p1->nInsert ){ + recoverFinalize(p, p1->pInsert); + p1->pInsert = recoverInsertStmt(p, pTab, p1->nVal); + p1->nInsert = p1->nVal; + } + if( p1->nVal>0 ){ + sqlite3_stmt *pInsert = p1->pInsert; + for(ii=0; ii<pTab->nCol; ii++){ + RecoverColumn *pCol = &pTab->aCol[ii]; + int iBind = pCol->iBind; + if( iBind>0 ){ + if( pCol->bIPK ){ + sqlite3_bind_int64(pInsert, iBind, p1->iRowid); + }else if( pCol->iField<p1->nVal ){ + recoverBindValue(p, pInsert, iBind, apVal[pCol->iField]); + } + } + } + if( p->bRecoverRowid && pTab->iRowidBind>0 && p1->bHaveRowid ){ + sqlite3_bind_int64(pInsert, pTab->iRowidBind, p1->iRowid); + } + if( SQLITE_ROW==sqlite3_step(pInsert) ){ + const char *z = (const char*)sqlite3_column_text(pInsert, 0); + recoverSqlCallback(p, z); + } + recoverReset(p, pInsert); + assert( p->errCode || pInsert ); + if( pInsert ) sqlite3_clear_bindings(pInsert); + } + } + + for(ii=0; ii<p1->nVal; ii++){ + sqlite3_value_free(apVal[ii]); + apVal[ii] = 0; + } + p1->nVal = -1; + p1->bHaveRowid = 0; + } + + if( iPage!=0 ){ + if( iField<0 ){ + p1->iRowid = sqlite3_column_int64(pSel, 3); + assert( p1->nVal==-1 ); + p1->nVal = 0; + p1->bHaveRowid = 1; + }else if( iField<pTab->nCol ){ + assert( apVal[iField]==0 ); + apVal[iField] = sqlite3_value_dup( pVal ); + if( apVal[iField]==0 ){ + recoverError(p, SQLITE_NOMEM, 0); + } + p1->nVal = iField+1; + } + p1->iPrevCell = iCell; + p1->iPrevPage = iPage; + } + }else{ + recoverReset(p, pSel); + p1->pTab = 0; + } + + return p->errCode; +} + +/* +** Initialize resources required by sqlite3_recover_step() in +** RECOVER_STATE_LOSTANDFOUND1 state - during which the set of pages not +** already allocated to a recovered schema element is determined. +*/ +static void recoverLostAndFound1Init(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + sqlite3_stmt *pStmt = 0; + + assert( p->laf.pUsed==0 ); + pLaf->nPg = recoverPageCount(p); + pLaf->pUsed = recoverBitmapAlloc(p, pLaf->nPg); + + /* Prepare a statement to iterate through all pages that are part of any tree + ** in the recoverable part of the input database schema to the bitmap. And, + ** if !p->bFreelistCorrupt, add all pages that appear to be part of the + ** freelist. */ + pStmt = recoverPrepare( + p, p->dbOut, + "WITH trunk(pgno) AS (" + " SELECT read_i32(getpage(1), 8) AS x WHERE x>0" + " UNION" + " SELECT read_i32(getpage(trunk.pgno), 0) AS x FROM trunk WHERE x>0" + ")," + "trunkdata(pgno, data) AS (" + " SELECT pgno, getpage(pgno) FROM trunk" + ")," + "freelist(data, n, freepgno) AS (" + " SELECT data, min(16384, read_i32(data, 1)-1), pgno FROM trunkdata" + " UNION ALL" + " SELECT data, n-1, read_i32(data, 2+n) FROM freelist WHERE n>=0" + ")," + "" + "roots(r) AS (" + " SELECT 1 UNION ALL" + " SELECT rootpage FROM recovery.schema WHERE rootpage>0" + ")," + "used(page) AS (" + " SELECT r FROM roots" + " UNION" + " SELECT child FROM sqlite_dbptr('getpage()'), used " + " WHERE pgno=page" + ") " + "SELECT page FROM used" + " UNION ALL " + "SELECT freepgno FROM freelist WHERE NOT ?" + ); + if( pStmt ) sqlite3_bind_int(pStmt, 1, p->bFreelistCorrupt); + pLaf->pUsedPages = pStmt; +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_LOSTANDFOUND1 state - during which the set of pages not +** already allocated to a recovered schema element is determined. +*/ +static int recoverLostAndFound1Step(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + int rc = p->errCode; + if( rc==SQLITE_OK ){ + rc = sqlite3_step(pLaf->pUsedPages); + if( rc==SQLITE_ROW ){ + i64 iPg = sqlite3_column_int64(pLaf->pUsedPages, 0); + recoverBitmapSet(pLaf->pUsed, iPg); + rc = SQLITE_OK; + }else{ + recoverFinalize(p, pLaf->pUsedPages); + pLaf->pUsedPages = 0; + } + } + return rc; +} + +/* +** Initialize resources required by RECOVER_STATE_LOSTANDFOUND2 +** state - during which the pages identified in RECOVER_STATE_LOSTANDFOUND1 +** are sorted into sets that likely belonged to the same database tree. +*/ +static void recoverLostAndFound2Init(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + + assert( p->laf.pAllAndParent==0 ); + assert( p->laf.pMapInsert==0 ); + assert( p->laf.pMaxField==0 ); + assert( p->laf.nMaxField==0 ); + + pLaf->pMapInsert = recoverPrepare(p, p->dbOut, + "INSERT OR IGNORE INTO recovery.map(pgno, parent) VALUES(?, ?)" + ); + pLaf->pAllAndParent = recoverPreparePrintf(p, p->dbOut, + "WITH RECURSIVE seq(ii) AS (" + " SELECT 1 UNION ALL SELECT ii+1 FROM seq WHERE ii<%lld" + ")" + "SELECT pgno, child FROM sqlite_dbptr('getpage()') " + " UNION ALL " + "SELECT NULL, ii FROM seq", p->laf.nPg + ); + pLaf->pMaxField = recoverPreparePrintf(p, p->dbOut, + "SELECT max(field)+1 FROM sqlite_dbdata('getpage') WHERE pgno = ?" + ); +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_LOSTANDFOUND2 state - during which the pages identified +** in RECOVER_STATE_LOSTANDFOUND1 are sorted into sets that likely belonged +** to the same database tree. +*/ +static int recoverLostAndFound2Step(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + if( p->errCode==SQLITE_OK ){ + int res = sqlite3_step(pLaf->pAllAndParent); + if( res==SQLITE_ROW ){ + i64 iChild = sqlite3_column_int(pLaf->pAllAndParent, 1); + if( recoverBitmapQuery(pLaf->pUsed, iChild)==0 ){ + sqlite3_bind_int64(pLaf->pMapInsert, 1, iChild); + sqlite3_bind_value(pLaf->pMapInsert, 2, + sqlite3_column_value(pLaf->pAllAndParent, 0) + ); + sqlite3_step(pLaf->pMapInsert); + recoverReset(p, pLaf->pMapInsert); + sqlite3_bind_int64(pLaf->pMaxField, 1, iChild); + if( SQLITE_ROW==sqlite3_step(pLaf->pMaxField) ){ + int nMax = sqlite3_column_int(pLaf->pMaxField, 0); + if( nMax>pLaf->nMaxField ) pLaf->nMaxField = nMax; + } + recoverReset(p, pLaf->pMaxField); + } + }else{ + recoverFinalize(p, pLaf->pAllAndParent); + pLaf->pAllAndParent =0; + return SQLITE_DONE; + } + } + return p->errCode; +} + +/* +** Free all resources allocated as part of sqlite3_recover_step() calls +** in one of the RECOVER_STATE_LOSTANDFOUND[123] states. +*/ +static void recoverLostAndFoundCleanup(sqlite3_recover *p){ + recoverBitmapFree(p->laf.pUsed); + p->laf.pUsed = 0; + sqlite3_finalize(p->laf.pUsedPages); + sqlite3_finalize(p->laf.pAllAndParent); + sqlite3_finalize(p->laf.pMapInsert); + sqlite3_finalize(p->laf.pMaxField); + sqlite3_finalize(p->laf.pFindRoot); + sqlite3_finalize(p->laf.pInsert); + sqlite3_finalize(p->laf.pAllPage); + sqlite3_finalize(p->laf.pPageData); + p->laf.pUsedPages = 0; + p->laf.pAllAndParent = 0; + p->laf.pMapInsert = 0; + p->laf.pMaxField = 0; + p->laf.pFindRoot = 0; + p->laf.pInsert = 0; + p->laf.pAllPage = 0; + p->laf.pPageData = 0; + sqlite3_free(p->laf.apVal); + p->laf.apVal = 0; +} + +/* +** Free all resources allocated as part of sqlite3_recover_step() calls. +*/ +static void recoverFinalCleanup(sqlite3_recover *p){ + RecoverTable *pTab = 0; + RecoverTable *pNext = 0; + + recoverWriteDataCleanup(p); + recoverLostAndFoundCleanup(p); + + for(pTab=p->pTblList; pTab; pTab=pNext){ + pNext = pTab->pNext; + sqlite3_free(pTab); + } + p->pTblList = 0; + sqlite3_finalize(p->pGetPage); + p->pGetPage = 0; + sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_RESET_CACHE, 0); + + { +#ifndef NDEBUG + int res = +#endif + sqlite3_close(p->dbOut); + assert( res==SQLITE_OK ); + } + p->dbOut = 0; +} + +/* +** Decode and return an unsigned 16-bit big-endian integer value from +** buffer a[]. +*/ +static u32 recoverGetU16(const u8 *a){ + return (((u32)a[0])<<8) + ((u32)a[1]); +} + +/* +** Decode and return an unsigned 32-bit big-endian integer value from +** buffer a[]. +*/ +static u32 recoverGetU32(const u8 *a){ + return (((u32)a[0])<<24) + (((u32)a[1])<<16) + (((u32)a[2])<<8) + ((u32)a[3]); +} + +/* +** Decode an SQLite varint from buffer a[]. Write the decoded value to (*pVal) +** and return the number of bytes consumed. +*/ +static int recoverGetVarint(const u8 *a, i64 *pVal){ + sqlite3_uint64 u = 0; + int i; + for(i=0; i<8; i++){ + u = (u<<7) + (a[i]&0x7f); + if( (a[i]&0x80)==0 ){ *pVal = (sqlite3_int64)u; return i+1; } + } + u = (u<<8) + (a[i]&0xff); + *pVal = (sqlite3_int64)u; + return 9; +} + +/* +** The second argument points to a buffer n bytes in size. If this buffer +** or a prefix thereof appears to contain a well-formed SQLite b-tree page, +** return the page-size in bytes. Otherwise, if the buffer does not +** appear to contain a well-formed b-tree page, return 0. +*/ +static int recoverIsValidPage(u8 *aTmp, const u8 *a, int n){ + u8 *aUsed = aTmp; + int nFrag = 0; + int nActual = 0; + int iFree = 0; + int nCell = 0; /* Number of cells on page */ + int iCellOff = 0; /* Offset of cell array in page */ + int iContent = 0; + int eType = 0; + int ii = 0; + + eType = (int)a[0]; + if( eType!=0x02 && eType!=0x05 && eType!=0x0A && eType!=0x0D ) return 0; + + iFree = (int)recoverGetU16(&a[1]); + nCell = (int)recoverGetU16(&a[3]); + iContent = (int)recoverGetU16(&a[5]); + if( iContent==0 ) iContent = 65536; + nFrag = (int)a[7]; + + if( iContent>n ) return 0; + + memset(aUsed, 0, n); + memset(aUsed, 0xFF, iContent); + + /* Follow the free-list. This is the same format for all b-tree pages. */ + if( iFree && iFree<=iContent ) return 0; + while( iFree ){ + int iNext = 0; + int nByte = 0; + if( iFree>(n-4) ) return 0; + iNext = recoverGetU16(&a[iFree]); + nByte = recoverGetU16(&a[iFree+2]); + if( iFree+nByte>n || nByte<4 ) return 0; + if( iNext && iNext<iFree+nByte ) return 0; + memset(&aUsed[iFree], 0xFF, nByte); + iFree = iNext; + } + + /* Run through the cells */ + if( eType==0x02 || eType==0x05 ){ + iCellOff = 12; + }else{ + iCellOff = 8; + } + if( (iCellOff + 2*nCell)>iContent ) return 0; + for(ii=0; ii<nCell; ii++){ + int iByte; + i64 nPayload = 0; + int nByte = 0; + int iOff = recoverGetU16(&a[iCellOff + 2*ii]); + if( iOff<iContent || iOff>n ){ + return 0; + } + if( eType==0x05 || eType==0x02 ) nByte += 4; + nByte += recoverGetVarint(&a[iOff+nByte], &nPayload); + if( eType==0x0D ){ + i64 dummy = 0; + nByte += recoverGetVarint(&a[iOff+nByte], &dummy); + } + if( eType!=0x05 ){ + int X = (eType==0x0D) ? n-35 : (((n-12)*64/255)-23); + int M = ((n-12)*32/255)-23; + int K = M+((nPayload-M)%(n-4)); + + if( nPayload<X ){ + nByte += nPayload; + }else if( K<=X ){ + nByte += K+4; + }else{ + nByte += M+4; + } + } + + if( iOff+nByte>n ){ + return 0; + } + for(iByte=iOff; iByte<(iOff+nByte); iByte++){ + if( aUsed[iByte]!=0 ){ + return 0; + } + aUsed[iByte] = 0xFF; + } + } + + nActual = 0; + for(ii=0; ii<n; ii++){ + if( aUsed[ii]==0 ) nActual++; + } + return (nActual==nFrag); +} + + +static int recoverVfsClose(sqlite3_file*); +static int recoverVfsRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); +static int recoverVfsWrite(sqlite3_file*, const void*, int, sqlite3_int64); +static int recoverVfsTruncate(sqlite3_file*, sqlite3_int64 size); +static int recoverVfsSync(sqlite3_file*, int flags); +static int recoverVfsFileSize(sqlite3_file*, sqlite3_int64 *pSize); +static int recoverVfsLock(sqlite3_file*, int); +static int recoverVfsUnlock(sqlite3_file*, int); +static int recoverVfsCheckReservedLock(sqlite3_file*, int *pResOut); +static int recoverVfsFileControl(sqlite3_file*, int op, void *pArg); +static int recoverVfsSectorSize(sqlite3_file*); +static int recoverVfsDeviceCharacteristics(sqlite3_file*); +static int recoverVfsShmMap(sqlite3_file*, int, int, int, void volatile**); +static int recoverVfsShmLock(sqlite3_file*, int offset, int n, int flags); +static void recoverVfsShmBarrier(sqlite3_file*); +static int recoverVfsShmUnmap(sqlite3_file*, int deleteFlag); +static int recoverVfsFetch(sqlite3_file*, sqlite3_int64, int, void**); +static int recoverVfsUnfetch(sqlite3_file *pFd, sqlite3_int64 iOff, void *p); + +static sqlite3_io_methods recover_methods = { + 2, /* iVersion */ + recoverVfsClose, + recoverVfsRead, + recoverVfsWrite, + recoverVfsTruncate, + recoverVfsSync, + recoverVfsFileSize, + recoverVfsLock, + recoverVfsUnlock, + recoverVfsCheckReservedLock, + recoverVfsFileControl, + recoverVfsSectorSize, + recoverVfsDeviceCharacteristics, + recoverVfsShmMap, + recoverVfsShmLock, + recoverVfsShmBarrier, + recoverVfsShmUnmap, + recoverVfsFetch, + recoverVfsUnfetch +}; + +static int recoverVfsClose(sqlite3_file *pFd){ + assert( pFd->pMethods!=&recover_methods ); + return pFd->pMethods->xClose(pFd); +} + +/* +** Write value v to buffer a[] as a 16-bit big-endian unsigned integer. +*/ +static void recoverPutU16(u8 *a, u32 v){ + a[0] = (v>>8) & 0x00FF; + a[1] = (v>>0) & 0x00FF; +} + +/* +** Write value v to buffer a[] as a 32-bit big-endian unsigned integer. +*/ +static void recoverPutU32(u8 *a, u32 v){ + a[0] = (v>>24) & 0x00FF; + a[1] = (v>>16) & 0x00FF; + a[2] = (v>>8) & 0x00FF; + a[3] = (v>>0) & 0x00FF; +} + +/* +** Detect the page-size of the database opened by file-handle pFd by +** searching the first part of the file for a well-formed SQLite b-tree +** page. If parameter nReserve is non-zero, then as well as searching for +** a b-tree page with zero reserved bytes, this function searches for one +** with nReserve reserved bytes at the end of it. +** +** If successful, set variable p->detected_pgsz to the detected page-size +** in bytes and return SQLITE_OK. Or, if no error occurs but no valid page +** can be found, return SQLITE_OK but leave p->detected_pgsz set to 0. Or, +** if an error occurs (e.g. an IO or OOM error), then an SQLite error code +** is returned. The final value of p->detected_pgsz is undefined in this +** case. +*/ +static int recoverVfsDetectPagesize( + sqlite3_recover *p, /* Recover handle */ + sqlite3_file *pFd, /* File-handle open on input database */ + u32 nReserve, /* Possible nReserve value */ + i64 nSz /* Size of database file in bytes */ +){ + int rc = SQLITE_OK; + const int nMin = 512; + const int nMax = 65536; + const int nMaxBlk = 4; + u32 pgsz = 0; + int iBlk = 0; + u8 *aPg = 0; + u8 *aTmp = 0; + int nBlk = 0; + + aPg = (u8*)sqlite3_malloc(2*nMax); + if( aPg==0 ) return SQLITE_NOMEM; + aTmp = &aPg[nMax]; + + nBlk = (nSz+nMax-1)/nMax; + if( nBlk>nMaxBlk ) nBlk = nMaxBlk; + + do { + for(iBlk=0; rc==SQLITE_OK && iBlk<nBlk; iBlk++){ + int nByte = (nSz>=((iBlk+1)*nMax)) ? nMax : (nSz % nMax); + memset(aPg, 0, nMax); + rc = pFd->pMethods->xRead(pFd, aPg, nByte, iBlk*nMax); + if( rc==SQLITE_OK ){ + int pgsz2; + for(pgsz2=(pgsz ? pgsz*2 : nMin); pgsz2<=nMax; pgsz2=pgsz2*2){ + int iOff; + for(iOff=0; iOff<nMax; iOff+=pgsz2){ + if( recoverIsValidPage(aTmp, &aPg[iOff], pgsz2-nReserve) ){ + pgsz = pgsz2; + break; + } + } + } + } + } + if( pgsz>(u32)p->detected_pgsz ){ + p->detected_pgsz = pgsz; + p->nReserve = nReserve; + } + if( nReserve==0 ) break; + nReserve = 0; + }while( 1 ); + + p->detected_pgsz = pgsz; + sqlite3_free(aPg); + return rc; +} + +/* +** The xRead() method of the wrapper VFS. This is used to intercept calls +** to read page 1 of the input database. +*/ +static int recoverVfsRead(sqlite3_file *pFd, void *aBuf, int nByte, i64 iOff){ + int rc = SQLITE_OK; + if( pFd->pMethods==&recover_methods ){ + pFd->pMethods = recover_g.pMethods; + rc = pFd->pMethods->xRead(pFd, aBuf, nByte, iOff); + if( nByte==16 ){ + sqlite3_randomness(16, aBuf); + }else + if( rc==SQLITE_OK && iOff==0 && nByte>=108 ){ + /* Ensure that the database has a valid header file. The only fields + ** that really matter to recovery are: + ** + ** + Database page size (16-bits at offset 16) + ** + Size of db in pages (32-bits at offset 28) + ** + Database encoding (32-bits at offset 56) + ** + ** Also preserved are: + ** + ** + first freelist page (32-bits at offset 32) + ** + size of freelist (32-bits at offset 36) + ** + the wal-mode flags (16-bits at offset 18) + ** + ** We also try to preserve the auto-vacuum, incr-value, user-version + ** and application-id fields - all 32 bit quantities at offsets + ** 52, 60, 64 and 68. All other fields are set to known good values. + ** + ** Byte offset 105 should also contain the page-size as a 16-bit + ** integer. + */ + const int aPreserve[] = {32, 36, 52, 60, 64, 68}; + u8 aHdr[108] = { + 0x53, 0x51, 0x4c, 0x69, 0x74, 0x65, 0x20, 0x66, + 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x20, 0x33, 0x00, + 0xFF, 0xFF, 0x01, 0x01, 0x00, 0x40, 0x20, 0x20, + 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, + 0x00, 0x00, 0x10, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x2e, 0x5b, 0x30, + + 0x0D, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x00 + }; + u8 *a = (u8*)aBuf; + + u32 pgsz = recoverGetU16(&a[16]); + u32 nReserve = a[20]; + u32 enc = recoverGetU32(&a[56]); + u32 dbsz = 0; + i64 dbFileSize = 0; + int ii; + sqlite3_recover *p = recover_g.p; + + if( pgsz==0x01 ) pgsz = 65536; + rc = pFd->pMethods->xFileSize(pFd, &dbFileSize); + + if( rc==SQLITE_OK && p->detected_pgsz==0 ){ + rc = recoverVfsDetectPagesize(p, pFd, nReserve, dbFileSize); + } + if( p->detected_pgsz ){ + pgsz = p->detected_pgsz; + nReserve = p->nReserve; + } + + if( pgsz ){ + dbsz = dbFileSize / pgsz; + } + if( enc!=SQLITE_UTF8 && enc!=SQLITE_UTF16BE && enc!=SQLITE_UTF16LE ){ + enc = SQLITE_UTF8; + } + + sqlite3_free(p->pPage1Cache); + p->pPage1Cache = 0; + p->pPage1Disk = 0; + + p->pgsz = nByte; + p->pPage1Cache = (u8*)recoverMalloc(p, nByte*2); + if( p->pPage1Cache ){ + p->pPage1Disk = &p->pPage1Cache[nByte]; + memcpy(p->pPage1Disk, aBuf, nByte); + aHdr[18] = a[18]; + aHdr[19] = a[19]; + recoverPutU32(&aHdr[28], dbsz); + recoverPutU32(&aHdr[56], enc); + recoverPutU16(&aHdr[105], pgsz-nReserve); + if( pgsz==65536 ) pgsz = 1; + recoverPutU16(&aHdr[16], pgsz); + aHdr[20] = nReserve; + for(ii=0; ii<(int)(sizeof(aPreserve)/sizeof(aPreserve[0])); ii++){ + memcpy(&aHdr[aPreserve[ii]], &a[aPreserve[ii]], 4); + } + memcpy(aBuf, aHdr, sizeof(aHdr)); + memset(&((u8*)aBuf)[sizeof(aHdr)], 0, nByte-sizeof(aHdr)); + + memcpy(p->pPage1Cache, aBuf, nByte); + }else{ + rc = p->errCode; + } + + } + pFd->pMethods = &recover_methods; + }else{ + rc = pFd->pMethods->xRead(pFd, aBuf, nByte, iOff); + } + return rc; +} + +/* +** Used to make sqlite3_io_methods wrapper methods less verbose. +*/ +#define RECOVER_VFS_WRAPPER(code) \ + int rc = SQLITE_OK; \ + if( pFd->pMethods==&recover_methods ){ \ + pFd->pMethods = recover_g.pMethods; \ + rc = code; \ + pFd->pMethods = &recover_methods; \ + }else{ \ + rc = code; \ + } \ + return rc; + +/* +** Methods of the wrapper VFS. All methods except for xRead() and xClose() +** simply uninstall the sqlite3_io_methods wrapper, invoke the equivalent +** method on the lower level VFS, then reinstall the wrapper before returning. +** Those that return an integer value use the RECOVER_VFS_WRAPPER macro. +*/ +static int recoverVfsWrite( + sqlite3_file *pFd, const void *aBuf, int nByte, i64 iOff +){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xWrite(pFd, aBuf, nByte, iOff) + ); +} +static int recoverVfsTruncate(sqlite3_file *pFd, sqlite3_int64 size){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xTruncate(pFd, size) + ); +} +static int recoverVfsSync(sqlite3_file *pFd, int flags){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xSync(pFd, flags) + ); +} +static int recoverVfsFileSize(sqlite3_file *pFd, sqlite3_int64 *pSize){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xFileSize(pFd, pSize) + ); +} +static int recoverVfsLock(sqlite3_file *pFd, int eLock){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xLock(pFd, eLock) + ); +} +static int recoverVfsUnlock(sqlite3_file *pFd, int eLock){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xUnlock(pFd, eLock) + ); +} +static int recoverVfsCheckReservedLock(sqlite3_file *pFd, int *pResOut){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xCheckReservedLock(pFd, pResOut) + ); +} +static int recoverVfsFileControl(sqlite3_file *pFd, int op, void *pArg){ + RECOVER_VFS_WRAPPER ( + (pFd->pMethods ? pFd->pMethods->xFileControl(pFd, op, pArg) : SQLITE_NOTFOUND) + ); +} +static int recoverVfsSectorSize(sqlite3_file *pFd){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xSectorSize(pFd) + ); +} +static int recoverVfsDeviceCharacteristics(sqlite3_file *pFd){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xDeviceCharacteristics(pFd) + ); +} +static int recoverVfsShmMap( + sqlite3_file *pFd, int iPg, int pgsz, int bExtend, void volatile **pp +){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xShmMap(pFd, iPg, pgsz, bExtend, pp) + ); +} +static int recoverVfsShmLock(sqlite3_file *pFd, int offset, int n, int flags){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xShmLock(pFd, offset, n, flags) + ); +} +static void recoverVfsShmBarrier(sqlite3_file *pFd){ + if( pFd->pMethods==&recover_methods ){ + pFd->pMethods = recover_g.pMethods; + pFd->pMethods->xShmBarrier(pFd); + pFd->pMethods = &recover_methods; + }else{ + pFd->pMethods->xShmBarrier(pFd); + } +} +static int recoverVfsShmUnmap(sqlite3_file *pFd, int deleteFlag){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xShmUnmap(pFd, deleteFlag) + ); +} + +static int recoverVfsFetch( + sqlite3_file *pFd, + sqlite3_int64 iOff, + int iAmt, + void **pp +){ + (void)pFd; + (void)iOff; + (void)iAmt; + *pp = 0; + return SQLITE_OK; +} +static int recoverVfsUnfetch(sqlite3_file *pFd, sqlite3_int64 iOff, void *p){ + (void)pFd; + (void)iOff; + (void)p; + return SQLITE_OK; +} + +/* +** Install the VFS wrapper around the file-descriptor open on the input +** database for recover handle p. Mutex RECOVER_MUTEX_ID must be held +** when this function is called. +*/ +static void recoverInstallWrapper(sqlite3_recover *p){ + sqlite3_file *pFd = 0; + assert( recover_g.pMethods==0 ); + recoverAssertMutexHeld(); + sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_FILE_POINTER, (void*)&pFd); + assert( pFd==0 || pFd->pMethods!=&recover_methods ); + if( pFd && pFd->pMethods ){ + int iVersion = 1 + (pFd->pMethods->iVersion>1 && pFd->pMethods->xShmMap!=0); + recover_g.pMethods = pFd->pMethods; + recover_g.p = p; + recover_methods.iVersion = iVersion; + pFd->pMethods = &recover_methods; + } +} + +/* +** Uninstall the VFS wrapper that was installed around the file-descriptor open +** on the input database for recover handle p. Mutex RECOVER_MUTEX_ID must be +** held when this function is called. +*/ +static void recoverUninstallWrapper(sqlite3_recover *p){ + sqlite3_file *pFd = 0; + recoverAssertMutexHeld(); + sqlite3_file_control(p->dbIn, p->zDb,SQLITE_FCNTL_FILE_POINTER,(void*)&pFd); + if( pFd && pFd->pMethods ){ + pFd->pMethods = recover_g.pMethods; + recover_g.pMethods = 0; + recover_g.p = 0; + } +} + +/* +** This function does the work of a single sqlite3_recover_step() call. It +** is guaranteed that the handle is not in an error state when this +** function is called. +*/ +static void recoverStep(sqlite3_recover *p){ + assert( p && p->errCode==SQLITE_OK ); + switch( p->eState ){ + case RECOVER_STATE_INIT: + /* This is the very first call to sqlite3_recover_step() on this object. + */ + recoverSqlCallback(p, "BEGIN"); + recoverSqlCallback(p, "PRAGMA writable_schema = on"); + + recoverEnterMutex(); + recoverInstallWrapper(p); + + /* Open the output database. And register required virtual tables and + ** user functions with the new handle. */ + recoverOpenOutput(p); + + /* Open transactions on both the input and output databases. */ + sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_RESET_CACHE, 0); + recoverExec(p, p->dbIn, "PRAGMA writable_schema = on"); + recoverExec(p, p->dbIn, "BEGIN"); + if( p->errCode==SQLITE_OK ) p->bCloseTransaction = 1; + recoverExec(p, p->dbIn, "SELECT 1 FROM sqlite_schema"); + recoverTransferSettings(p); + recoverOpenRecovery(p); + recoverCacheSchema(p); + + recoverUninstallWrapper(p); + recoverLeaveMutex(); + + recoverExec(p, p->dbOut, "BEGIN"); + + recoverWriteSchema1(p); + p->eState = RECOVER_STATE_WRITING; + break; + + case RECOVER_STATE_WRITING: { + if( p->w1.pTbls==0 ){ + recoverWriteDataInit(p); + } + if( SQLITE_DONE==recoverWriteDataStep(p) ){ + recoverWriteDataCleanup(p); + if( p->zLostAndFound ){ + p->eState = RECOVER_STATE_LOSTANDFOUND1; + }else{ + p->eState = RECOVER_STATE_SCHEMA2; + } + } + break; + } + + case RECOVER_STATE_LOSTANDFOUND1: { + if( p->laf.pUsed==0 ){ + recoverLostAndFound1Init(p); + } + if( SQLITE_DONE==recoverLostAndFound1Step(p) ){ + p->eState = RECOVER_STATE_LOSTANDFOUND2; + } + break; + } + case RECOVER_STATE_LOSTANDFOUND2: { + if( p->laf.pAllAndParent==0 ){ + recoverLostAndFound2Init(p); + } + if( SQLITE_DONE==recoverLostAndFound2Step(p) ){ + p->eState = RECOVER_STATE_LOSTANDFOUND3; + } + break; + } + + case RECOVER_STATE_LOSTANDFOUND3: { + if( p->laf.pInsert==0 ){ + recoverLostAndFound3Init(p); + } + if( SQLITE_DONE==recoverLostAndFound3Step(p) ){ + p->eState = RECOVER_STATE_SCHEMA2; + } + break; + } + + case RECOVER_STATE_SCHEMA2: { + int rc = SQLITE_OK; + + recoverWriteSchema2(p); + p->eState = RECOVER_STATE_DONE; + + /* If no error has occurred, commit the write transaction on the output + ** database. Regardless of whether or not an error has occurred, make + ** an attempt to end the read transaction on the input database. */ + recoverExec(p, p->dbOut, "COMMIT"); + rc = sqlite3_exec(p->dbIn, "END", 0, 0, 0); + if( p->errCode==SQLITE_OK ) p->errCode = rc; + + recoverSqlCallback(p, "PRAGMA writable_schema = off"); + recoverSqlCallback(p, "COMMIT"); + p->eState = RECOVER_STATE_DONE; + recoverFinalCleanup(p); + break; + }; + + case RECOVER_STATE_DONE: { + /* no-op */ + break; + }; + } +} + + +/* +** This is a worker function that does the heavy lifting for both init +** functions: +** +** sqlite3_recover_init() +** sqlite3_recover_init_sql() +** +** All this function does is allocate space for the recover handle and +** take copies of the input parameters. All the real work is done within +** sqlite3_recover_run(). +*/ +sqlite3_recover *recoverInit( + sqlite3* db, + const char *zDb, + const char *zUri, /* Output URI for _recover_init() */ + int (*xSql)(void*, const char*),/* SQL callback for _recover_init_sql() */ + void *pSqlCtx /* Context arg for _recover_init_sql() */ +){ + sqlite3_recover *pRet = 0; + int nDb = 0; + int nUri = 0; + int nByte = 0; + + if( zDb==0 ){ zDb = "main"; } + + nDb = recoverStrlen(zDb); + nUri = recoverStrlen(zUri); + + nByte = sizeof(sqlite3_recover) + nDb+1 + nUri+1; + pRet = (sqlite3_recover*)sqlite3_malloc(nByte); + if( pRet ){ + memset(pRet, 0, nByte); + pRet->dbIn = db; + pRet->zDb = (char*)&pRet[1]; + pRet->zUri = &pRet->zDb[nDb+1]; + memcpy(pRet->zDb, zDb, nDb); + if( nUri>0 && zUri ) memcpy(pRet->zUri, zUri, nUri); + pRet->xSql = xSql; + pRet->pSqlCtx = pSqlCtx; + pRet->bRecoverRowid = RECOVER_ROWID_DEFAULT; + } + + return pRet; +} + +/* +** Initialize a recovery handle that creates a new database containing +** the recovered data. +*/ +sqlite3_recover *sqlite3_recover_init( + sqlite3* db, + const char *zDb, + const char *zUri +){ + return recoverInit(db, zDb, zUri, 0, 0); +} + +/* +** Initialize a recovery handle that returns recovered data in the +** form of SQL statements via a callback. +*/ +sqlite3_recover *sqlite3_recover_init_sql( + sqlite3* db, + const char *zDb, + int (*xSql)(void*, const char*), + void *pSqlCtx +){ + return recoverInit(db, zDb, 0, xSql, pSqlCtx); +} + +/* +** Return the handle error message, if any. +*/ +const char *sqlite3_recover_errmsg(sqlite3_recover *p){ + return (p && p->errCode!=SQLITE_NOMEM) ? p->zErrMsg : "out of memory"; +} + +/* +** Return the handle error code. +*/ +int sqlite3_recover_errcode(sqlite3_recover *p){ + return p ? p->errCode : SQLITE_NOMEM; +} + +/* +** Configure the handle. +*/ +int sqlite3_recover_config(sqlite3_recover *p, int op, void *pArg){ + int rc = SQLITE_OK; + if( p==0 ){ + rc = SQLITE_NOMEM; + }else if( p->eState!=RECOVER_STATE_INIT ){ + rc = SQLITE_MISUSE; + }else{ + switch( op ){ + case 789: + /* This undocumented magic configuration option is used to set the + ** name of the auxiliary database that is ATTACH-ed to the database + ** connection and used to hold state information during the + ** recovery process. This option is for debugging use only and + ** is subject to change or removal at any time. */ + sqlite3_free(p->zStateDb); + p->zStateDb = recoverMPrintf(p, "%s", (char*)pArg); + break; + + case SQLITE_RECOVER_LOST_AND_FOUND: { + const char *zArg = (const char*)pArg; + sqlite3_free(p->zLostAndFound); + if( zArg ){ + p->zLostAndFound = recoverMPrintf(p, "%s", zArg); + }else{ + p->zLostAndFound = 0; + } + break; + } + + case SQLITE_RECOVER_FREELIST_CORRUPT: + p->bFreelistCorrupt = *(int*)pArg; + break; + + case SQLITE_RECOVER_ROWIDS: + p->bRecoverRowid = *(int*)pArg; + break; + + case SQLITE_RECOVER_SLOWINDEXES: + p->bSlowIndexes = *(int*)pArg; + break; + + default: + rc = SQLITE_NOTFOUND; + break; + } + } + + return rc; +} + +/* +** Do a unit of work towards the recovery job. Return SQLITE_OK if +** no error has occurred but database recovery is not finished, SQLITE_DONE +** if database recovery has been successfully completed, or an SQLite +** error code if an error has occurred. +*/ +int sqlite3_recover_step(sqlite3_recover *p){ + if( p==0 ) return SQLITE_NOMEM; + if( p->errCode==SQLITE_OK ) recoverStep(p); + if( p->eState==RECOVER_STATE_DONE && p->errCode==SQLITE_OK ){ + return SQLITE_DONE; + } + return p->errCode; +} + +/* +** Do the configured recovery operation. Return SQLITE_OK if successful, or +** else an SQLite error code. +*/ +int sqlite3_recover_run(sqlite3_recover *p){ + while( SQLITE_OK==sqlite3_recover_step(p) ); + return sqlite3_recover_errcode(p); +} + + +/* +** Free all resources associated with the recover handle passed as the only +** argument. The results of using a handle with any sqlite3_recover_** +** API function after it has been passed to this function are undefined. +** +** A copy of the value returned by the first call made to sqlite3_recover_run() +** on this handle is returned, or SQLITE_OK if sqlite3_recover_run() has +** not been called on this handle. +*/ +int sqlite3_recover_finish(sqlite3_recover *p){ + int rc; + if( p==0 ){ + rc = SQLITE_NOMEM; + }else{ + recoverFinalCleanup(p); + if( p->bCloseTransaction && sqlite3_get_autocommit(p->dbIn)==0 ){ + rc = sqlite3_exec(p->dbIn, "END", 0, 0, 0); + if( p->errCode==SQLITE_OK ) p->errCode = rc; + } + rc = p->errCode; + sqlite3_free(p->zErrMsg); + sqlite3_free(p->zStateDb); + sqlite3_free(p->zLostAndFound); + sqlite3_free(p->pPage1Cache); + sqlite3_free(p); + } + return rc; +} + +#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */ +#pragma GCC diagnostic pop |