Update test_fs.c to include a virtual table that reads a file-system hierarchy. Use it to further test GLOB and LIKE support for virtual tables.

FossilOrigin-Name: 6ef6578c03b7cfbeaaf3627b9eea2febf501ace5

src/test_fs.c

@@ -29,6 +29,37 @@
 ** Adding the row to the idx table automatically creates a row in the 
 ** virtual table with rowid=4, path=/etc/passwd and a text field that 
 ** contains data read from file /etc/passwd on disk.
+**
+*************************************************************************
+** Virtual table module "fsdir"
+**
+** This module is designed to be used as a read-only eponymous virtual table.
+** Its schema is as follows:
+**
+**   CREATE TABLE fsdir(dir TEXT, name TEXT);
+**
+** When queried, a WHERE term of the form "dir = $dir" must be provided. The
+** virtual table then appears to have one row for each entry in file-system
+** directory $dir. Column dir contains a copy of $dir, and column "name"
+** contains the name of the directory entry.
+**
+** If the specified $dir cannot be opened or is not a directory, it is not
+** an error. The virtual table appears to be empty in this case.
+**
+*************************************************************************
+** Virtual table module "fstree"
+**
+** This module is also a read-only eponymous virtual table with the 
+** following schema:
+**
+**   CREATE TABLE fstree(path TEXT, size INT, data BLOB);
+**
+** Running a "SELECT * FROM fstree" query on this table returns the entire
+** contents of the file-system, starting at "/". To restrict the search
+** space, the virtual table supports LIKE and GLOB constraints on the
+** 'path' column. For example:
+**
+**   SELECT * FROM fstree WHERE path LIKE '/home/dan/sqlite/%'
 */
 #include "sqliteInt.h"
 #include "tcl.h"
@@ -41,6 +72,7 @@
 
 #if SQLITE_OS_UNIX
 # include <unistd.h>
+# include <dirent.h>
 #endif
 #if SQLITE_OS_WIN
 # include <io.h>
@@ -70,6 +102,463 @@ struct fs_cursor {
   int nAlloc;
 };
 
+/*************************************************************************
+** Start of fsdir implementation.
+*/
+typedef struct FsdirVtab FsdirVtab;
+typedef struct FsdirCsr FsdirCsr;
+struct FsdirVtab {
+  sqlite3_vtab base;
+};
+
+struct FsdirCsr {
+  sqlite3_vtab_cursor base;
+  char *zDir;                     /* Buffer containing directory scanned */
+  DIR *pDir;                      /* Open directory */
+  sqlite3_int64 iRowid;
+  struct dirent entry;            /* Current entry */
+};
+
+/*
+** This function is the implementation of both the xConnect and xCreate
+** methods of the fsdir virtual table.
+**
+** The argv[] array contains the following:
+**
+**   argv[0]   -> module name  ("fs")
+**   argv[1]   -> database name
+**   argv[2]   -> table name
+**   argv[...] -> other module argument fields.
+*/
+static int fsdirConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  FsdirVtab *pTab;
+
+  if( argc!=3 ){
+    *pzErr = sqlite3_mprintf("wrong number of arguments");
+    return SQLITE_ERROR;
+  }
+
+  pTab = (FsdirVtab *)sqlite3_malloc(sizeof(FsdirVtab));
+  if( !pTab ) return SQLITE_NOMEM;
+  memset(pTab, 0, sizeof(FsdirVtab));
+
+  *ppVtab = &pTab->base;
+  sqlite3_declare_vtab(db, "CREATE TABLE xyz(dir, name);");
+
+  return SQLITE_OK;
+}
+
+/*
+** xDestroy/xDisconnect implementation.
+*/
+static int fsdirDisconnect(sqlite3_vtab *pVtab){
+  sqlite3_free(pVtab);
+  return SQLITE_OK;
+}
+
+/*
+** xBestIndex implementation. The only constraint supported is:
+**
+**   (dir = ?)
+*/
+static int fsdirBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+  int ii;
+
+  pIdxInfo->estimatedCost = 1000000000.0;
+
+  for(ii=0; ii<pIdxInfo->nConstraint; ii++){
+    struct sqlite3_index_constraint const *p = &pIdxInfo->aConstraint[ii];
+    if( p->iColumn==0 && p->usable && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+      struct sqlite3_index_constraint_usage *pUsage;
+      pUsage = &pIdxInfo->aConstraintUsage[ii];
+      pUsage->omit = 1;
+      pUsage->argvIndex = 1;
+      pIdxInfo->idxNum = 1;
+      pIdxInfo->estimatedCost = 1.0;
+      break;
+    }
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** xOpen implementation.
+**
+** Open a new fsdir cursor.
+*/
+static int fsdirOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  FsdirCsr *pCur;
+  pCur = (FsdirCsr*)sqlite3_malloc(sizeof(FsdirCsr));
+  if( pCur==0 ) return SQLITE_NOMEM;
+  memset(pCur, 0, sizeof(FsdirCsr));
+  *ppCursor = &pCur->base;
+  return SQLITE_OK;
+}
+
+/*
+** Close a fsdir cursor.
+*/
+static int fsdirClose(sqlite3_vtab_cursor *cur){
+  FsdirCsr *pCur = (FsdirCsr*)cur;
+  if( pCur->pDir ) closedir(pCur->pDir);
+  sqlite3_free(pCur->zDir);
+  sqlite3_free(pCur);
+  return SQLITE_OK;
+}
+
+/*
+** Skip the cursor to the next entry.
+*/
+static int fsdirNext(sqlite3_vtab_cursor *cur){
+  FsdirCsr *pCsr = (FsdirCsr*)cur;
+
+  if( pCsr->pDir ){
+    struct dirent *pRes = 0;
+    readdir_r(pCsr->pDir, &pCsr->entry, &pRes);
+    if( pRes==0 ){
+      closedir(pCsr->pDir);
+      pCsr->pDir = 0;
+    }
+    pCsr->iRowid++;
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** xFilter method implementation.
+*/
+static int fsdirFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  FsdirCsr *pCsr = (FsdirCsr*)pVtabCursor;
+  int rc;
+  const char *zDir;
+  int nDir;
+
+
+  if( idxNum!=1 || argc!=1 ){
+    return SQLITE_ERROR;
+  }
+
+  pCsr->iRowid = 0;
+  sqlite3_free(pCsr->zDir);
+  if( pCsr->pDir ){
+    closedir(pCsr->pDir);
+    pCsr->pDir = 0;
+  }
+
+  zDir = (const char*)sqlite3_value_text(argv[0]);
+  nDir = sqlite3_value_bytes(argv[0]);
+  pCsr->zDir = sqlite3_malloc(nDir+1);
+  if( pCsr->zDir==0 ) return SQLITE_NOMEM;
+  memcpy(pCsr->zDir, zDir, nDir+1);
+
+  pCsr->pDir = opendir(pCsr->zDir);
+  return fsdirNext(pVtabCursor); 
+}
+
+/*
+** xEof method implementation.
+*/
+static int fsdirEof(sqlite3_vtab_cursor *cur){
+  FsdirCsr *pCsr = (FsdirCsr*)cur;
+  return pCsr->pDir==0;
+}
+
+/*
+** xColumn method implementation.
+*/
+static int fsdirColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+  FsdirCsr *pCsr = (FsdirCsr*)cur;
+  switch( i ){
+    case 0: /* dir */
+      sqlite3_result_text(ctx, pCsr->zDir, -1, SQLITE_STATIC);
+      break;
+
+    case 1: /* name */
+      sqlite3_result_text(ctx, pCsr->entry.d_name, -1, SQLITE_TRANSIENT);
+      break;
+
+    default:
+      assert( 0 );
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** xRowid method implementation.
+*/
+static int fsdirRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  FsdirCsr *pCsr = (FsdirCsr*)cur;
+  *pRowid = pCsr->iRowid;
+  return SQLITE_OK;
+}
+/*
+** End of fsdir implementation.
+*************************************************************************/
+
+/*************************************************************************
+** Start of fstree implementation.
+*/
+typedef struct FstreeVtab FstreeVtab;
+typedef struct FstreeCsr FstreeCsr;
+struct FstreeVtab {
+  sqlite3_vtab base;
+  sqlite3 *db;
+};
+
+struct FstreeCsr {
+  sqlite3_vtab_cursor base;
+  sqlite3_stmt *pStmt;            /* Statement to list paths */
+  int fd;                         /* File descriptor open on current path */
+};
+
+/*
+** This function is the implementation of both the xConnect and xCreate
+** methods of the fstree virtual table.
+**
+** The argv[] array contains the following:
+**
+**   argv[0]   -> module name  ("fs")
+**   argv[1]   -> database name
+**   argv[2]   -> table name
+**   argv[...] -> other module argument fields.
+*/
+static int fstreeConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  FstreeVtab *pTab;
+
+  if( argc!=3 ){
+    *pzErr = sqlite3_mprintf("wrong number of arguments");
+    return SQLITE_ERROR;
+  }
+
+  pTab = (FstreeVtab *)sqlite3_malloc(sizeof(FstreeVtab));
+  if( !pTab ) return SQLITE_NOMEM;
+  memset(pTab, 0, sizeof(FstreeVtab));
+  pTab->db = db;
+
+  *ppVtab = &pTab->base;
+  sqlite3_declare_vtab(db, "CREATE TABLE xyz(path, size, data);");
+
+  return SQLITE_OK;
+}
+
+/*
+** xDestroy/xDisconnect implementation.
+*/
+static int fstreeDisconnect(sqlite3_vtab *pVtab){
+  sqlite3_free(pVtab);
+  return SQLITE_OK;
+}
+
+/*
+** xBestIndex implementation. The only constraint supported is:
+**
+**   (dir = ?)
+*/
+static int fstreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+  int ii;
+
+  for(ii=0; ii<pIdxInfo->nConstraint; ii++){
+    struct sqlite3_index_constraint const *p = &pIdxInfo->aConstraint[ii];
+    if( p->iColumn==0 && p->usable && (
+          p->op==SQLITE_INDEX_CONSTRAINT_GLOB
+       || p->op==SQLITE_INDEX_CONSTRAINT_LIKE
+       || p->op==SQLITE_INDEX_CONSTRAINT_EQ
+    )){
+      struct sqlite3_index_constraint_usage *pUsage;
+      pUsage = &pIdxInfo->aConstraintUsage[ii];
+      pIdxInfo->idxNum = p->op;
+      pUsage->argvIndex = 1;
+      pIdxInfo->estimatedCost = 100000.0;
+      return SQLITE_OK;
+    }
+  }
+
+  pIdxInfo->estimatedCost = 1000000000.0;
+  return SQLITE_OK;
+}
+
+/*
+** xOpen implementation.
+**
+** Open a new fstree cursor.
+*/
+static int fstreeOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  FstreeCsr *pCur;
+  pCur = (FstreeCsr*)sqlite3_malloc(sizeof(FstreeCsr));
+  if( pCur==0 ) return SQLITE_NOMEM;
+  memset(pCur, 0, sizeof(FstreeCsr));
+  pCur->fd = -1;
+  *ppCursor = &pCur->base;
+  return SQLITE_OK;
+}
+
+static void fstreeCloseFd(FstreeCsr *pCsr){
+  if( pCsr->fd>=0 ){
+    close(pCsr->fd);
+    pCsr->fd = -1;
+  }
+}
+
+/*
+** Close a fstree cursor.
+*/
+static int fstreeClose(sqlite3_vtab_cursor *cur){
+  FstreeCsr *pCsr = (FstreeCsr*)cur;
+  sqlite3_finalize(pCsr->pStmt);
+  fstreeCloseFd(pCsr);
+  sqlite3_free(pCsr);
+  return SQLITE_OK;
+}
+
+/*
+** Skip the cursor to the next entry.
+*/
+static int fstreeNext(sqlite3_vtab_cursor *cur){
+  FstreeCsr *pCsr = (FstreeCsr*)cur;
+  int rc;
+
+  fstreeCloseFd(pCsr);
+  rc = sqlite3_step(pCsr->pStmt);
+  if( rc!=SQLITE_ROW ){
+    rc = sqlite3_finalize(pCsr->pStmt);
+    pCsr->pStmt = 0;
+  }else{
+    rc = SQLITE_OK;
+    pCsr->fd = open(sqlite3_column_text(pCsr->pStmt, 0), O_RDONLY);
+  }
+
+  return rc;
+}
+
+/*
+** xFilter method implementation.
+*/
+static int fstreeFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  FstreeCsr *pCsr = (FstreeCsr*)pVtabCursor;
+  FstreeVtab *pTab = (FstreeVtab*)(pCsr->base.pVtab);
+  int rc;
+  const char *zSql = 
+"WITH r(d) AS ("
+"  SELECT CASE WHEN dir='/' THEN '' ELSE dir END || '/' || name "
+"    FROM fsdir WHERE dir=? AND name NOT LIKE '.%'"
+"  UNION ALL"
+"  SELECT dir || '/' || name FROM r, fsdir WHERE dir=d AND name NOT LIKE '.%'"
+") SELECT d FROM r;";
+
+  const char *zDir = "/";
+  int nDir = 1;
+  char aWild[2] = {'\0', '\0' };
+
+  fstreeCloseFd(pCsr);
+  sqlite3_finalize(pCsr->pStmt);
+  pCsr->pStmt = 0;
+  rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pStmt, 0);
+  if( rc!=SQLITE_OK ) return rc;
+
+  if( idxNum ){
+    const char *zQuery = (const char*)sqlite3_value_text(argv[0]);
+    switch( idxNum ){
+      case SQLITE_INDEX_CONSTRAINT_GLOB:
+        aWild[0] = '*';
+        aWild[1] = '?';
+        break;
+      case SQLITE_INDEX_CONSTRAINT_LIKE:
+        aWild[0] = '_';
+        aWild[1] = '%';
+        break;
+    }
+
+    if( zQuery[0]=='/' ){
+      int i;
+      for(i=1; zQuery[i]; i++){
+        if( zQuery[i]==aWild[0] || zQuery[i]==aWild[1] ) break;
+        if( zQuery[i]=='/' ) nDir = i;
+      }
+      zDir = zQuery;
+    }
+  }
+
+  sqlite3_bind_text(pCsr->pStmt, 1, zDir, nDir, SQLITE_TRANSIENT);
+
+  return fstreeNext(pVtabCursor); 
+}
+
+/*
+** xEof method implementation.
+*/
+static int fstreeEof(sqlite3_vtab_cursor *cur){
+  FstreeCsr *pCsr = (FstreeCsr*)cur;
+  return pCsr->pStmt==0;
+}
+
+/*
+** xColumn method implementation.
+*/
+static int fstreeColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+  FstreeCsr *pCsr = (FstreeCsr*)cur;
+  if( i==0 ){      /* path */
+    sqlite3_result_value(ctx, sqlite3_column_value(pCsr->pStmt, 0));
+  }else{
+    struct stat sBuf;
+    fstat(pCsr->fd, &sBuf);
+
+    if( S_ISREG(sBuf.st_mode) ){
+      if( i==1 ){
+        sqlite3_result_int64(ctx, sBuf.st_size);
+      }else{
+        int nRead;
+        char *aBuf = sqlite3_malloc(sBuf.st_mode+1);
+        if( !aBuf ) return SQLITE_NOMEM;
+        nRead = read(pCsr->fd, aBuf, sBuf.st_mode);
+        if( nRead!=sBuf.st_mode ){
+          return SQLITE_IOERR;
+        }
+        sqlite3_result_blob(ctx, aBuf, nRead, SQLITE_TRANSIENT);
+        sqlite3_free(aBuf);
+      }
+    }
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** xRowid method implementation.
+*/
+static int fstreeRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  *pRowid = 0;
+  return SQLITE_OK;
+}
+/*
+** End of fstree implementation.
+*************************************************************************/
+
+
+
+
 /*
 ** This function is the implementation of both the xConnect and xCreate
 ** methods of the fs virtual table.
@@ -109,7 +598,7 @@ static int fsConnect(
   memcpy(pVtab->zTbl, zTbl, strlen(zTbl));
   memcpy(pVtab->zDb, zDb, strlen(zDb));
   *ppVtab = &pVtab->base;
-  sqlite3_declare_vtab(db, "CREATE TABLE xyz(path TEXT, data TEXT)");
+  sqlite3_declare_vtab(db, "CREATE TABLE x(path TEXT, data TEXT)");
 
   return SQLITE_OK;
 }
@@ -188,15 +677,15 @@ static int fsFilter(
 static int fsColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
   fs_cursor *pCur = (fs_cursor*)cur;
 
-  assert( i==0 || i==1 );
+  assert( i==0 || i==1 || i==2 );
   if( i==0 ){
     sqlite3_result_value(ctx, sqlite3_column_value(pCur->pStmt, 0));
   }else{
     const char *zFile = (const char *)sqlite3_column_text(pCur->pStmt, 1);
     struct stat sbuf;
     int fd;
-    int n;
 
+    int n;
     fd = open(zFile, O_RDONLY);
     if( fd<0 ) return SQLITE_IOERR;
     fstat(fd, &sbuf);
@@ -284,6 +773,52 @@ static sqlite3_module fsModule = {
   0,                           /* xRename */
 };
 
+static sqlite3_module fsdirModule = {
+  0,                              /* iVersion */
+  fsdirConnect,                   /* xCreate */
+  fsdirConnect,                   /* xConnect */
+  fsdirBestIndex,                 /* xBestIndex */
+  fsdirDisconnect,                /* xDisconnect */
+  fsdirDisconnect,                /* xDestroy */
+  fsdirOpen,                      /* xOpen - open a cursor */
+  fsdirClose,                     /* xClose - close a cursor */
+  fsdirFilter,                    /* xFilter - configure scan constraints */
+  fsdirNext,                      /* xNext - advance a cursor */
+  fsdirEof,                       /* xEof - check for end of scan */
+  fsdirColumn,                    /* xColumn - read data */
+  fsdirRowid,                     /* xRowid - read data */
+  0,                              /* xUpdate */
+  0,                              /* xBegin */
+  0,                              /* xSync */
+  0,                              /* xCommit */
+  0,                              /* xRollback */
+  0,                              /* xFindMethod */
+  0,                              /* xRename */
+};
+
+static sqlite3_module fstreeModule = {
+  0,                              /* iVersion */
+  fstreeConnect,                  /* xCreate */
+  fstreeConnect,                  /* xConnect */
+  fstreeBestIndex,                /* xBestIndex */
+  fstreeDisconnect,               /* xDisconnect */
+  fstreeDisconnect,               /* xDestroy */
+  fstreeOpen,                     /* xOpen - open a cursor */
+  fstreeClose,                    /* xClose - close a cursor */
+  fstreeFilter,                   /* xFilter - configure scan constraints */
+  fstreeNext,                     /* xNext - advance a cursor */
+  fstreeEof,                      /* xEof - check for end of scan */
+  fstreeColumn,                   /* xColumn - read data */
+  fstreeRowid,                    /* xRowid - read data */
+  0,                              /* xUpdate */
+  0,                              /* xBegin */
+  0,                              /* xSync */
+  0,                              /* xCommit */
+  0,                              /* xRollback */
+  0,                              /* xFindMethod */
+  0,                              /* xRename */
+};
+
 /*
 ** Decode a pointer to an sqlite3 object.
 */
@@ -306,6 +841,8 @@ static int register_fs_module(
   if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   sqlite3_create_module(db, "fs", &fsModule, (void *)interp);
+  sqlite3_create_module(db, "fsdir", &fsdirModule, 0);
+  sqlite3_create_module(db, "fstree", &fstreeModule, 0);
 #endif
   return TCL_OK;
 }