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Overview
Comment: | Add new extension "checkfreelist", which uses sqlite_dbpage to check that there are no invalid entries on the database free-list. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | dbpage |
Files: | files | file ages | folders |
SHA3-256: |
21930ef5376261d95fa325be7761d327 |
User & Date: | dan 2017-10-11 18:00:34.689 |
Context
2017-10-11
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18:21 | Check that the leaf count on each freelist trunk page is in range as part of checkfreelist processing. (check-in: 4e89406248 user: dan tags: dbpage) | |
18:00 | Add new extension "checkfreelist", which uses sqlite_dbpage to check that there are no invalid entries on the database free-list. (check-in: 21930ef537 user: dan tags: dbpage) | |
17:51 | Convert the implementation of the ".dbstat" dot-command of the command-line shell to use the sqlite_dbpage table. (check-in: 497409e167 user: drh tags: dbpage) | |
Changes
Added ext/misc/checkfreelist.c.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 | /* ** 2017 October 11 ** ** 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 module exports a single C function: ** ** int sqlite3_check_freelist(sqlite3 *db, const char *zDb); ** ** This function checks the free-list in database zDb (one of "main", ** "temp", etc.) and reports any errors by invoking the sqlite3_log() ** function. It returns SQLITE_OK if successful, or an SQLite error ** code otherwise. It is not an error if the free-list is corrupted but ** no IO or OOM errors occur. ** ** If this file is compiled and loaded as an SQLite loadable extension, ** it adds an SQL function "checkfreelist" to the database handle, to ** be invoked as follows: ** ** SELECT checkfreelist(<database-name>); ** ** This function performs the same checks as sqlite3_check_freelist(), ** except that it returns all error messages as a single text value, ** separated by newline characters. If the freelist is not corrupted ** in any way, an empty string is returned. ** ** To compile this module for use as an SQLite loadable extension: ** ** gcc -Os -fPIC -shared checkfreelist.c -o checkfreelist.so */ #include "sqlite3ext.h" SQLITE_EXTENSION_INIT1 #ifndef SQLITE_AMALGAMATION # include <string.h> # include <stdio.h> # include <stdlib.h> # include <assert.h> # define ALWAYS(X) 1 # define NEVER(X) 0 typedef unsigned char u8; typedef unsigned short u16; typedef unsigned int u32; #define get4byte(x) ( \ ((u32)((x)[0])<<24) + \ ((u32)((x)[1])<<16) + \ ((u32)((x)[2])<<8) + \ ((u32)((x)[3])) \ ) #endif /* ** Execute a single PRAGMA statement and return the integer value returned ** via output parameter (*pnOut). ** ** The SQL statement passed as the third argument should be a printf-style ** format string containing a single "%s" which will be replace by the ** value passed as the second argument. e.g. ** ** sqlGetInteger(db, "main", "PRAGMA %s.page_count", pnOut) ** ** executes "PRAGMA main.page_count" and stores the results in (*pnOut). */ static int sqlGetInteger( sqlite3 *db, /* Database handle */ const char *zDb, /* Database name ("main", "temp" etc.) */ const char *zFmt, /* SQL statement format */ u32 *pnOut /* OUT: Integer value */ ){ int rc, rc2; char *zSql; sqlite3_stmt *pStmt = 0; int bOk = 0; zSql = sqlite3_mprintf(zFmt, zDb); if( zSql==0 ){ rc = SQLITE_NOMEM; }else{ rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0); sqlite3_free(zSql); } if( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){ *pnOut = (u32)sqlite3_column_int(pStmt, 0); bOk = 1; } rc2 = sqlite3_finalize(pStmt); if( rc==SQLITE_OK ) rc = rc2; if( rc==SQLITE_OK && bOk==0 ) rc = SQLITE_ERROR; return rc; } /* ** Argument zFmt must be a printf-style format string and must be ** followed by its required arguments. If argument pzOut is NULL, ** then the results of printf()ing the format string are passed to ** sqlite3_log(). Otherwise, they are appended to the string ** at (*pzOut). */ static int checkFreelistError(char **pzOut, const char *zFmt, ...){ int rc = SQLITE_OK; char *zErr = 0; va_list ap; va_start(ap, zFmt); zErr = sqlite3_vmprintf(zFmt, ap); if( zErr==0 ){ rc = SQLITE_NOMEM; }else{ if( pzOut ){ *pzOut = sqlite3_mprintf("%s%z%s", *pzOut?"\n":"", *pzOut, zErr); if( *pzOut==0 ) rc = SQLITE_NOMEM; }else{ sqlite3_log(SQLITE_ERROR, "checkfreelist: %s", zErr); } sqlite3_free(zErr); } va_end(ap); return rc; } static int checkFreelist( sqlite3 *db, const char *zDb, char **pzOut ){ /* This query returns one row for each page on the free list. Each row has ** two columns - the page number and page content. */ const char *zTrunk = "WITH freelist_trunk(i, d, n) AS (" "SELECT 1, NULL, sqlite_readint32(data, 32) " "FROM sqlite_dbpage(:1) WHERE pgno=1 " "UNION ALL " "SELECT n, data, sqlite_readint32(data) " "FROM freelist_trunk, sqlite_dbpage(:1) WHERE pgno=n " ")" "SELECT i, d FROM freelist_trunk WHERE i!=1;"; int rc, rc2; /* Return code */ sqlite3_stmt *pTrunk = 0; /* Compilation of zTrunk */ u32 nPage = 0; /* Number of pages in db */ u32 nExpected = 0; /* Expected number of free pages */ u32 nFree = 0; /* Number of pages on free list */ if( zDb==0 ) zDb = "main"; if( (rc = sqlGetInteger(db, zDb, "PRAGMA %s.page_count", &nPage)) || (rc = sqlGetInteger(db, zDb, "PRAGMA %s.freelist_count", &nExpected)) ){ return rc; } rc = sqlite3_prepare_v2(db, zTrunk, -1, &pTrunk, 0); if( rc!=SQLITE_OK ) return rc; sqlite3_bind_text(pTrunk, 1, zDb, -1, SQLITE_STATIC); while( rc==SQLITE_OK && sqlite3_step(pTrunk)==SQLITE_ROW ){ u32 i; u32 iTrunk = (u32)sqlite3_column_int(pTrunk, 0); const u8 *aData = (const u8*)sqlite3_column_blob(pTrunk, 1); int nData = sqlite3_column_bytes(pTrunk, 1); u32 iNext = get4byte(&aData[0]); u32 nLeaf = get4byte(&aData[4]); nFree += 1+nLeaf; if( iNext>nPage ){ rc = checkFreelistError(pzOut, "trunk page %d is out of range", (int)iNext ); } for(i=0; rc==SQLITE_OK && i<nLeaf; i++){ u32 iLeaf = get4byte(&aData[8 + 4*i]); if( iLeaf==0 || iLeaf>nPage ){ rc = checkFreelistError(pzOut, "leaf page %d is out of range (child %d of trunk page %d)", (int)iLeaf, (int)i, (int)iTrunk ); } } } if( rc==SQLITE_OK && nFree!=nExpected ){ rc = checkFreelistError(pzOut, "free-list count mismatch: actual=%d header=%d", (int)nFree, (int)nExpected ); } rc2 = sqlite3_finalize(pTrunk); if( rc==SQLITE_OK ) rc = rc2; return rc; } int sqlite3_check_freelist(sqlite3 *db, const char *zDb){ return checkFreelist(db, zDb, 0); } static void checkfreelist_function( sqlite3_context *pCtx, int nArg, sqlite3_value **apArg ){ const char *zDb; int rc; char *zOut = 0; sqlite3 *db = sqlite3_context_db_handle(pCtx); assert( nArg==1 ); zDb = sqlite3_value_text(apArg[0]); rc = checkFreelist(db, zDb, &zOut); if( rc==SQLITE_OK ){ sqlite3_result_text(pCtx, zOut?zOut:"ok", -1, SQLITE_TRANSIENT); }else{ sqlite3_result_error_code(pCtx, rc); } sqlite3_free(zOut); } /* ** An SQL function invoked as follows: ** ** sqlite_readint32(BLOB) -- Decode 32-bit integer from start of blob */ static void readint_function( sqlite3_context *pCtx, int nArg, sqlite3_value **apArg ){ const u8 *zBlob; int nBlob; int iOff = 0; u32 iRet = 0; if( nArg!=1 && nArg!=2 ){ sqlite3_result_error( pCtx, "wrong number of arguments to function sqlite_readint32()", -1 ); return; } if( nArg==2 ){ iOff = sqlite3_value_int(apArg[1]); } zBlob = sqlite3_value_blob(apArg[0]); nBlob = sqlite3_value_bytes(apArg[0]); if( nBlob>=(iOff+4) ){ iRet = get4byte(&zBlob[iOff]); } sqlite3_result_int64(pCtx, (sqlite3_int64)iRet); } /* ** Register the SQL functions. */ static int cflRegister(sqlite3 *db){ int rc = sqlite3_create_function( db, "sqlite_readint32", -1, SQLITE_UTF8, 0, readint_function, 0, 0 ); if( rc!=SQLITE_OK ) return rc; rc = sqlite3_create_function( db, "checkfreelist", 1, SQLITE_UTF8, 0, checkfreelist_function, 0, 0 ); return rc; } /* ** Extension load function. */ #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_checkfreelist_init( sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi ){ SQLITE_EXTENSION_INIT2(pApi); return cflRegister(db); } |
Added test/checkfreelist.test.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 | # 2017-10-11 # # 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 regression tests for SQLite library. The # focus of this file is testing the checkfreelist extension. # set testdir [file dirname $argv0] source $testdir/tester.tcl set testprefix checkfreelist ifcapable !vtab||!compound { finish_test return } if {[file exists ../checkfreelist.so]==0} { finish_test return } do_execsql_test 1.0 { CREATE TABLE t1(a, b); } db enable_load_extension 1 do_execsql_test 1.1 { SELECT load_extension('../checkfreelist.so'); } {{}} do_execsql_test 1.2 { SELECT checkfreelist('main') } {ok} do_execsql_test 1.3 { WITH s(i) AS ( SELECT 1 UNION ALL SELECT i+1 FROM s WHERE i<10000 ) INSERT INTO t1 SELECT randomblob(400), randomblob(400) FROM s; DELETE FROM t1 WHERE rowid%3; PRAGMA freelist_count; } {6726} do_execsql_test 1.4 { SELECT checkfreelist('main') } {ok} do_execsql_test 1.5 { WITH freelist_trunk(i, d, n) AS ( SELECT 1, NULL, sqlite_readint32(data, 32) FROM sqlite_dbpage WHERE pgno=1 UNION ALL SELECT n, data, sqlite_readint32(data) FROM freelist_trunk, sqlite_dbpage WHERE pgno=n ) SELECT i FROM freelist_trunk WHERE i!=1; } { 10010 9716 9344 8970 8596 8223 7848 7475 7103 6728 6355 5983 5609 5235 4861 4488 4113 3741 3368 2993 2620 2248 1873 1500 1126 753 378 5 } do_execsql_test 1.6 { SELECT checkfreelist('main') } {ok} proc set_int {blob idx newval} { binary scan $blob I* ints lset ints $idx $newval binary format I* $ints } db func set_int set_int proc get_int {blob idx} { binary scan $blob I* ints lindex $ints $idx } db func get_int get_int do_execsql_test 1.7 { BEGIN; UPDATE sqlite_dbpage SET data = set_int(data, 1, get_int(data, 1)-1) WHERE pgno=4861; SELECT checkfreelist('main'); ROLLBACK; } {{free-list count mismatch: actual=6725 header=6726}} do_execsql_test 1.8 { BEGIN; UPDATE sqlite_dbpage SET data = set_int(data, 5, (SELECT * FROM pragma_page_count)+1) WHERE pgno=4861; SELECT checkfreelist('main'); ROLLBACK; } {{leaf page 10093 is out of range (child 3 of trunk page 4861)}} do_execsql_test 1.9 { BEGIN; UPDATE sqlite_dbpage SET data = set_int(data, 5, 0) WHERE pgno=4861; SELECT checkfreelist('main'); ROLLBACK; } {{leaf page 0 is out of range (child 3 of trunk page 4861)}} do_execsql_test 1.10 { BEGIN; UPDATE sqlite_dbpage SET data = set_int(data, get_int(data, 1)+1, 0) WHERE pgno=5; SELECT checkfreelist('main'); ROLLBACK; } {{leaf page 0 is out of range (child 247 of trunk page 5)}} finish_test |