[sql] Import reference version of SQLite 3.8.7.4.

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

 /*
 ** 2010 April 7
 **
 ** 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.
 **
 *************************************************************************
 **
-** An example of a simple VFS implementation that omits complex features
-** often not required or not possible on embedded platforms. Also includes
-** code to buffer writes to the journal file, which can be a significant
-** performance improvement on some embedded platforms.
+** This file implements an example of a simple VFS implementation that 
+** omits complex features often not required or not possible on embedded
+** platforms.  Code is included to buffer writes to the journal file, 
+** which can be a significant performance improvement on some embedded
+** platforms.
 **
-*/
-
-/*
 ** OVERVIEW
 **
 **   The code in this file implements a minimal SQLite VFS that can be 
 **   used on Linux and other posix-like operating systems. The following 
 **   system calls are used:
 **
 **    File-system: access(), unlink(), getcwd()
 **    File IO:     open(), read(), write(), fsync(), close(), fstat()
 **    Other:       sleep(), usleep(), time()
 **
@@ skipping 90 matching lines @@
 
 #include <assert.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/file.h>
 #include <sys/param.h>
 #include <unistd.h>
 #include <time.h>
 #include <errno.h>
+#include <fcntl.h>
 
 /*
 ** Size of the write buffer used by journal files in bytes.
 */
 #ifndef SQLITE_DEMOVFS_BUFFERSZ
 # define SQLITE_DEMOVFS_BUFFERSZ 8192
 #endif
 
 /*
 ** The maximum pathname length supported by this VFS.
@@ skipping 389 matching lines @@
 static int demoFullPathname(
   sqlite3_vfs *pVfs,              /* VFS */
   const char *zPath,              /* Input path (possibly a relative path) */
   int nPathOut,                   /* Size of output buffer in bytes */
   char *zPathOut                  /* Pointer to output buffer */
 ){
   char zDir[MAXPATHNAME+1];
   if( zPath[0]=='/' ){
     zDir[0] = '\0';
   }else{
-    getcwd(zDir, sizeof(zDir));
+    if( getcwd(zDir, sizeof(zDir))==0 ) return SQLITE_IOERR;
   }
   zDir[MAXPATHNAME] = '\0';
 
   sqlite3_snprintf(nPathOut, zPathOut, "%s/%s", zDir, zPath);
   zPathOut[nPathOut-1] = '\0';
 
   return SQLITE_OK;
 }
 
 /*
@@ skipping 120 matching lines @@
   Tcl_CreateObjCommand(interp, "register_demovfs", register_demovfs, 0, 0);
   Tcl_CreateObjCommand(interp, "unregister_demovfs", unregister_demovfs, 0, 0);
   return TCL_OK;
 }
 
 #else
 int Sqlitetest_demovfs_Init(Tcl_Interp *interp){ return TCL_OK; }
 #endif
 
 #endif /* SQLITE_TEST */