third_party/sqlite/sqlite-src-3080704/src/test_fs.c

   1 /*
   2 ** 2013 Jan 11
   3 **
   4 ** The author disclaims copyright to this source code.  In place of
   5 ** a legal notice, here is a blessing:
   6 **
   7 **    May you do good and not evil.
   8 **    May you find forgiveness for yourself and forgive others.
   9 **    May you share freely, never taking more than you give.
  10 **
  11 *************************************************************************
  12 ** Code for testing the virtual table interfaces.  This code
  13 ** is not included in the SQLite library.  It is used for automated
  14 ** testing of the SQLite library.
  15 **
  16 ** The FS virtual table is created as follows:
  17 **
  18 **   CREATE VIRTUAL TABLE tbl USING fs(idx);
  19 **
  20 ** where idx is the name of a table in the db with 2 columns.  The virtual
  21 ** table also has two columns - file path and file contents.
  22 **
  23 ** The first column of table idx must be an IPK, and the second contains file
  24 ** paths. For example:
  25 **
  26 **   CREATE TABLE idx(id INTEGER PRIMARY KEY, path TEXT);
  27 **   INSERT INTO idx VALUES(4, '/etc/passwd');
  28 **
  29 ** Adding the row to the idx table automatically creates a row in the
  30 ** virtual table with rowid=4, path=/etc/passwd and a text field that
  31 ** contains data read from file /etc/passwd on disk.
  32 */
  33 #include "sqliteInt.h"
  34 #include "tcl.h"
  35
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40 #include <fcntl.h>
  41
  42 #if SQLITE_OS_UNIX
  43 # include <unistd.h>
  44 #endif
  45 #if SQLITE_OS_WIN
  46 # include <io.h>
  47 #endif
  48
  49 #ifndef SQLITE_OMIT_VIRTUALTABLE
  50
  51 typedef struct fs_vtab fs_vtab;
  52 typedef struct fs_cursor fs_cursor;
  53
  54 /*
  55 ** A fs virtual-table object
  56 */
  57 struct fs_vtab {
  58   sqlite3_vtab base;
  59   sqlite3 *db;
  60   char *zDb;                      /* Name of db containing zTbl */
  61   char *zTbl;                     /* Name of docid->file map table */
  62 };
  63
  64 /* A fs cursor object */
  65 struct fs_cursor {
  66   sqlite3_vtab_cursor base;
  67   sqlite3_stmt *pStmt;
  68   char *zBuf;
  69   int nBuf;
  70   int nAlloc;
  71 };
  72
  73 /*
  74 ** This function is the implementation of both the xConnect and xCreate
  75 ** methods of the fs virtual table.
  76 **
  77 ** The argv[] array contains the following:
  78 **
  79 **   argv[0]   -> module name  ("fs")
  80 **   argv[1]   -> database name
  81 **   argv[2]   -> table name
  82 **   argv[...] -> other module argument fields.
  83 */
  84 static int fsConnect(
  85   sqlite3 *db,
  86   void *pAux,
  87   int argc, const char *const*argv,
  88   sqlite3_vtab **ppVtab,
  89   char **pzErr
  90 ){
  91   fs_vtab *pVtab;
  92   int nByte;
  93   const char *zTbl;
  94   const char *zDb = argv[1];
  95
  96   if( argc!=4 ){
  97     *pzErr = sqlite3_mprintf("wrong number of arguments");
  98     return SQLITE_ERROR;
  99   }
 100   zTbl = argv[3];
 101
 102   nByte = sizeof(fs_vtab) + (int)strlen(zTbl) + 1 + (int)strlen(zDb) + 1;
 103   pVtab = (fs_vtab *)sqlite3MallocZero( nByte );
 104   if( !pVtab ) return SQLITE_NOMEM;
 105
 106   pVtab->zTbl = (char *)&pVtab[1];
 107   pVtab->zDb = &pVtab->zTbl[strlen(zTbl)+1];
 108   pVtab->db = db;
 109   memcpy(pVtab->zTbl, zTbl, strlen(zTbl));
 110   memcpy(pVtab->zDb, zDb, strlen(zDb));
 111   *ppVtab = &pVtab->base;
 112   sqlite3_declare_vtab(db, "CREATE TABLE xyz(path TEXT, data TEXT)");
 113
 114   return SQLITE_OK;
 115 }
 116 /* Note that for this virtual table, the xCreate and xConnect
 117 ** methods are identical. */
 118
 119 static int fsDisconnect(sqlite3_vtab *pVtab){
 120   sqlite3_free(pVtab);
 121   return SQLITE_OK;
 122 }
 123 /* The xDisconnect and xDestroy methods are also the same */
 124
 125 /*
 126 ** Open a new fs cursor.
 127 */
 128 static int fsOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
 129   fs_cursor *pCur;
 130   pCur = sqlite3MallocZero(sizeof(fs_cursor));
 131   *ppCursor = &pCur->base;
 132   return SQLITE_OK;
 133 }
 134
 135 /*
 136 ** Close a fs cursor.
 137 */
 138 static int fsClose(sqlite3_vtab_cursor *cur){
 139   fs_cursor *pCur = (fs_cursor *)cur;
 140   sqlite3_finalize(pCur->pStmt);
 141   sqlite3_free(pCur->zBuf);
 142   sqlite3_free(pCur);
 143   return SQLITE_OK;
 144 }
 145
 146 static int fsNext(sqlite3_vtab_cursor *cur){
 147   fs_cursor *pCur = (fs_cursor *)cur;
 148   int rc;
 149
 150   rc = sqlite3_step(pCur->pStmt);
 151   if( rc==SQLITE_ROW || rc==SQLITE_DONE ) rc = SQLITE_OK;
 152
 153   return rc;
 154 }
 155
 156 static int fsFilter(
 157   sqlite3_vtab_cursor *pVtabCursor,
 158   int idxNum, const char *idxStr,
 159   int argc, sqlite3_value **argv
 160 ){
 161   int rc;
 162   fs_cursor *pCur = (fs_cursor *)pVtabCursor;
 163   fs_vtab *p = (fs_vtab *)(pVtabCursor->pVtab);
 164
 165   assert( (idxNum==0 && argc==0) || (idxNum==1 && argc==1) );
 166   if( idxNum==1 ){
 167     char *zStmt = sqlite3_mprintf(
 168         "SELECT * FROM %Q.%Q WHERE rowid=?", p->zDb, p->zTbl);
 169     if( !zStmt ) return SQLITE_NOMEM;
 170     rc = sqlite3_prepare_v2(p->db, zStmt, -1, &pCur->pStmt, 0);
 171     sqlite3_free(zStmt);
 172     if( rc==SQLITE_OK ){
 173       sqlite3_bind_value(pCur->pStmt, 1, argv[0]);
 174     }
 175   }else{
 176     char *zStmt = sqlite3_mprintf("SELECT * FROM %Q.%Q", p->zDb, p->zTbl);
 177     if( !zStmt ) return SQLITE_NOMEM;
 178     rc = sqlite3_prepare_v2(p->db, zStmt, -1, &pCur->pStmt, 0);
 179     sqlite3_free(zStmt);
 180   }
 181
 182   if( rc==SQLITE_OK ){
 183     rc = fsNext(pVtabCursor);
 184   }
 185   return rc;
 186 }
 187
 188 static int fsColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
 189   fs_cursor *pCur = (fs_cursor*)cur;
 190
 191   assert( i==0 || i==1 );
 192   if( i==0 ){
 193     sqlite3_result_value(ctx, sqlite3_column_value(pCur->pStmt, 0));
 194   }else{
 195     const char *zFile = (const char *)sqlite3_column_text(pCur->pStmt, 1);
 196     struct stat sbuf;
 197     int fd;
 198     int n;
 199
 200     fd = open(zFile, O_RDONLY);
 201     if( fd<0 ) return SQLITE_IOERR;
 202     fstat(fd, &sbuf);
 203
 204     if( sbuf.st_size>=pCur->nAlloc ){
 205       int nNew = sbuf.st_size*2;
 206       char *zNew;
 207       if( nNew<1024 ) nNew = 1024;
 208
 209       zNew = sqlite3Realloc(pCur->zBuf, nNew);
 210       if( zNew==0 ){
 211         close(fd);
 212         return SQLITE_NOMEM;
 213       }
 214       pCur->zBuf = zNew;
 215       pCur->nAlloc = nNew;
 216     }
 217
 218     n = (int)read(fd, pCur->zBuf, sbuf.st_size);
 219     close(fd);
 220     if( n!=sbuf.st_size ) return SQLITE_ERROR;
 221     pCur->nBuf = sbuf.st_size;
 222     pCur->zBuf[pCur->nBuf] = '\0';
 223
 224     sqlite3_result_text(ctx, pCur->zBuf, -1, SQLITE_TRANSIENT);
 225   }
 226   return SQLITE_OK;
 227 }
 228
 229 static int fsRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
 230   fs_cursor *pCur = (fs_cursor*)cur;
 231   *pRowid = sqlite3_column_int64(pCur->pStmt, 0);
 232   return SQLITE_OK;
 233 }
 234
 235 static int fsEof(sqlite3_vtab_cursor *cur){
 236   fs_cursor *pCur = (fs_cursor*)cur;
 237   return (sqlite3_data_count(pCur->pStmt)==0);
 238 }
 239
 240 static int fsBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
 241   int ii;
 242
 243   for(ii=0; ii<pIdxInfo->nConstraint; ii++){
 244     struct sqlite3_index_constraint const *pCons = &pIdxInfo->aConstraint[ii];
 245     if( pCons->iColumn<0 && pCons->usable
 246            && pCons->op==SQLITE_INDEX_CONSTRAINT_EQ ){
 247       struct sqlite3_index_constraint_usage *pUsage;
 248       pUsage = &pIdxInfo->aConstraintUsage[ii];
 249       pUsage->omit = 0;
 250       pUsage->argvIndex = 1;
 251       pIdxInfo->idxNum = 1;
 252       pIdxInfo->estimatedCost = 1.0;
 253       break;
 254     }
 255   }
 256
 257   return SQLITE_OK;
 258 }
 259
 260 /*
 261 ** A virtual table module that provides read-only access to a
 262 ** Tcl global variable namespace.
 263 */
 264 static sqlite3_module fsModule = {
 265   0,                         /* iVersion */
 266   fsConnect,
 267   fsConnect,
 268   fsBestIndex,
 269   fsDisconnect,
 270   fsDisconnect,
 271   fsOpen,                      /* xOpen - open a cursor */
 272   fsClose,                     /* xClose - close a cursor */
 273   fsFilter,                    /* xFilter - configure scan constraints */
 274   fsNext,                      /* xNext - advance a cursor */
 275   fsEof,                       /* xEof - check for end of scan */
 276   fsColumn,                    /* xColumn - read data */
 277   fsRowid,                     /* xRowid - read data */
 278   0,                           /* xUpdate */
 279   0,                           /* xBegin */
 280   0,                           /* xSync */
 281   0,                           /* xCommit */
 282   0,                           /* xRollback */
 283   0,                           /* xFindMethod */
 284   0,                           /* xRename */
 285 };
 286
 287 /*
 288 ** Decode a pointer to an sqlite3 object.
 289 */
 290 extern int getDbPointer(Tcl_Interp *interp, const char *zA, sqlite3 **ppDb);
 291
 292 /*
 293 ** Register the echo virtual table module.
 294 */
 295 static int register_fs_module(
 296   ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
 297   Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
 298   int objc,              /* Number of arguments */
 299   Tcl_Obj *CONST objv[]  /* Command arguments */
 300 ){
 301   sqlite3 *db;
 302   if( objc!=2 ){
 303     Tcl_WrongNumArgs(interp, 1, objv, "DB");
 304     return TCL_ERROR;
 305   }
 306   if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
 307 #ifndef SQLITE_OMIT_VIRTUALTABLE
 308   sqlite3_create_module(db, "fs", &fsModule, (void *)interp);
 309 #endif
 310   return TCL_OK;
 311 }
 312
 313 #endif
 314
 315
 316 /*
 317 ** Register commands with the TCL interpreter.
 318 */
 319 int Sqlitetestfs_Init(Tcl_Interp *interp){
 320 #ifndef SQLITE_OMIT_VIRTUALTABLE
 321   static struct {
 322      char *zName;
 323      Tcl_ObjCmdProc *xProc;
 324      void *clientData;
 325   } aObjCmd[] = {
 326      { "register_fs_module",   register_fs_module, 0 },
 327   };
 328   int i;
 329   for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
 330     Tcl_CreateObjCommand(interp, aObjCmd[i].zName,
 331         aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
 332   }
 333 #endif
 334   return TCL_OK;
 335 }