SQLite

/*
** 2014-06-13
**
** 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 SQLite extension implements SQL functions readfile() and
** writefile(), and eponymous virtual type "fsdir".
**
** WRITEFILE(FILE, DATA [, MODE [, MTIME]]):
**
**   If neither of the optional arguments is present, then this UDF
**   function writes blob DATA to file FILE. If successful, the number
**   of bytes written is returned. If an error occurs, NULL is returned.
**
**   If the first option argument - MODE - is present, then it must
**   be passed an integer value that corresponds to a POSIX mode
**   value (file type + permissions, as returned in the stat.st_mode
**   field by the stat() system call). Three types of files may
**   be written/created:
**
**     regular files:  (mode & 0170000)==0100000
**     symbolic links: (mode & 0170000)==0120000
**     directories:    (mode & 0170000)==0040000
**
**   For a directory, the DATA is ignored. For a symbolic link, it is
**   interpreted as text and used as the target of the link. For a
**   regular file, it is interpreted as a blob and written into the
**   named file. Regardless of the type of file, its permissions are
**   set to (mode & 0777) before returning.
**
**   If the optional MTIME argument is present, then it is interpreted
**   as an integer - the number of seconds since the unix epoch. The
**   modification-time of the target file is set to this value before
**   returning.
**
**   If three or more arguments are passed to this function and an
**   error is encountered, an exception is raised.
**
** READFILE(FILE):
**
**   Read and return the contents of file FILE (type blob) from disk.
**
** FSDIR:
**
**   Used as follows:
**
**     SELECT * FROM fsdir($path [, $dir]);
**
**   Parameter $path is an absolute or relative pathname. If the file that it
**   refers to does not exist, it is an error. If the path refers to a regular
**   file or symbolic link, it returns a single row. Or, if the path refers
**   to a directory, it returns one row for the directory, and one row for each
**   file within the hierarchy rooted at $path.
**
**   Each row has the following columns:
**
**     name:  Path to file or directory (text value).
**     mode:  Value of stat.st_mode for directory entry (an integer).
**     mtime: Value of stat.st_mtime for directory entry (an integer).
**     data:  For a regular file, a blob containing the file data. For a
**            symlink, a text value containing the text of the link. For a
**            directory, NULL.
**
**   If a non-NULL value is specified for the optional $dir parameter and
**   $path is a relative path, then $path is interpreted relative to $dir. 
**   And the paths returned in the "name" column of the table are also 
**   relative to directory $dir.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdio.h>
#include <string.h>
#include <assert.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <dirent.h>
#include <time.h>
#include <utime.h>
#include <errno.h>


#define FSDIR_SCHEMA "(name,mode,mtime,data,path HIDDEN,dir HIDDEN)"

/*
** Set the result stored by context ctx to a blob containing the 
** contents of file zName.
*/
static void readFileContents(sqlite3_context *ctx, const char *zName){
  FILE *in;
  long nIn;
  void *pBuf;

  in = fopen(zName, "rb");
  if( in==0 ) return;

  const char *zName;
  (void)(argc);  /* Unused parameter */
  zName = (const char*)sqlite3_value_text(argv[0]);
  if( zName==0 ) return;
  readFileContents(context, zName);
}

/*
** Set the error message contained in context ctx to the results of
** vprintf(zFmt, ...).
*/
static void ctxErrorMsg(sqlite3_context *ctx, const char *zFmt, ...){
  char *zMsg = 0;
  va_list ap;
  va_start(ap, zFmt);
  zMsg = sqlite3_vmprintf(zFmt, ap);
  sqlite3_result_error(ctx, zMsg, -1);
  sqlite3_free(zMsg);

    sqlite3_free(zCopy);
  }

  return rc;
}

/*
** This function does the work for the writefile() UDF. Refer to 
** header comments at the top of this file for details.
*/
static int writeFile(
  sqlite3_context *pCtx,          /* Context to return bytes written in */
  const char *zFile,              /* File to write */

  sqlite3_value *pData,           /* Data to write */
  mode_t mode,                    /* MODE parameter passed to writefile() */
  sqlite3_int64 mtime             /* MTIME parameter (or -1 to not set time) */
){
  if( S_ISLNK(mode) ){
    const char *zTo = (const char*)sqlite3_value_text(pData);
    if( symlink(zTo, zFile)<0 ) return 1;
  }else{
    if( S_ISDIR(mode) ){
      if( mkdir(zFile, mode) ){

        sqlite3_int64 n = fwrite(z, 1, sqlite3_value_bytes(pData), out);
        nWrite = sqlite3_value_bytes(pData);
        if( nWrite!=n ){
          rc = 1;
        }
      }
      fclose(out);
      if( rc==0 && mode && chmod(zFile, mode & 0777) ){
        rc = 1;
      }
      if( rc ) return 2;
      sqlite3_result_int64(pCtx, nWrite);
    }
  }

  if( mtime>=0 ){
    struct timespec times[2];
    times[0].tv_nsec = times[1].tv_nsec = 0;
    times[0].tv_sec = time(0);
    times[1].tv_sec = mtime;
    if( utimensat(AT_FDCWD, zFile, times, AT_SYMLINK_NOFOLLOW) ){
      return 1;
    }
  }

  return 0;
}

/*
** Implementation of the "writefile(W,X[,Y[,Z]]])" SQL function.  
** Refer to header comments at the top of this file for details.



*/
static void writefileFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const char *zFile;
  mode_t mode = 0;
  int res;
  sqlite3_int64 mtime = -1;

  if( argc<2 || argc>4 ){
    sqlite3_result_error(context, 
        "wrong number of arguments to function writefile()", -1
    );
    return;
  }

  zFile = (const char*)sqlite3_value_text(argv[0]);
  if( zFile==0 ) return;
  if( argc>=3 ){

    mode = sqlite3_value_int(argv[2]);
  }
  if( argc==4 ){
    mtime = sqlite3_value_int64(argv[3]);
  }

  res = writeFile(context, zFile, argv[1], mode, mtime);
  if( res==1 && errno==ENOENT ){
    if( makeDirectory(zFile, mode)==SQLITE_OK ){
      res = writeFile(context, zFile, argv[1], mode, mtime);
    }
  }

  if( argc>2 && res!=0 ){
    if( S_ISLNK(mode) ){
      ctxErrorMsg(context, "failed to create symlink: %s", zFile);
    }else if( S_ISDIR(mode) ){
      ctxErrorMsg(context, "failed to create directory: %s", zFile);
    }else{
      ctxErrorMsg(context, "failed to write file: %s", zFile);
    }

  if( pCur==0 ) return SQLITE_NOMEM;
  memset(pCur, 0, sizeof(*pCur));
  pCur->iLvl = -1;
  *ppCursor = &pCur->base;
  return SQLITE_OK;
}

/*
** Reset a cursor back to the state it was in when first returned
** by fsdirOpen().
*/
static void fsdirResetCursor(fsdir_cursor *pCur){
  int i;
  for(i=0; i<=pCur->iLvl; i++){
    FsdirLevel *pLvl = &pCur->aLvl[i];
    if( pLvl->pDir ) closedir(pLvl->pDir);
    sqlite3_free(pLvl->zDir);
  }

  fsdirResetCursor(pCur);
  sqlite3_free(pCur->aLvl);
  sqlite3_free(pCur);
  return SQLITE_OK;
}

/*
** Set the error message for the virtual table associated with cursor
** pCur to the results of vprintf(zFmt, ...).
*/
static void fsdirSetErrmsg(fsdir_cursor *pCur, const char *zFmt, ...){
  va_list ap;
  va_start(ap, zFmt);
  pCur->base.pVtab->zErrMsg = sqlite3_vmprintf(zFmt, ap);
  va_end(ap);
}

      pIdxInfo->estimatedCost = 100.0;
    }
  }

  return SQLITE_OK;
}

/*
** Register the "fsdir" virtual table.
*/
static int fsdirRegister(sqlite3 *db){
  static sqlite3_module fsdirModule = {
    0,                         /* iVersion */
    0,                         /* xCreate */
    fsdirConnect,              /* xConnect */
    fsdirBestIndex,            /* xBestIndex */
    fsdirDisconnect,           /* xDisconnect */

    0,                         /* xCommit */
    0,                         /* xRollback */
    0,                         /* xFindMethod */
    0,                         /* xRename */
  };

  int rc = sqlite3_create_module(db, "fsdir", &fsdirModule, 0);



  return rc;
}
#else         /* SQLITE_OMIT_VIRTUALTABLE */
# define fsdirRegister(x) SQLITE_OK
#endif

#ifdef _WIN32

          sqlite3_errmsg(db), sqlite3_errcode(db)
      );
      *pRc = rc;
    }
  }
}

static void shellPreparePrintf(
  sqlite3 *db, 
  int *pRc, 


  sqlite3_stmt **ppStmt,
  const char *zFmt, 
  ...
){
  *ppStmt = 0;
  if( *pRc==SQLITE_OK ){
    va_list ap;
    char *z;
    va_start(ap, zFmt);
    z = sqlite3_vmprintf(zFmt, ap);
    if( z==0 ){
      *pRc = SQLITE_NOMEM;
    }else{
      shellPrepare(db, pRc, z, ppStmt);
      sqlite3_free(z);
    }


  }
}

static void shellFinalize(
  int *pRc, 
  sqlite3_stmt *pStmt
){

** in (*pAr). Leave this WHERE clause in (*pzWhere) before returning.
** The caller is responsible for eventually calling sqlite3_free() on
** any non-NULL (*pzWhere) value.
*/
static void arWhereClause(
  int *pRc, 
  ArCommand *pAr, 
  char **pzWhere                  /* OUT: New WHERE clause */
){
  char *zWhere = 0;
  if( *pRc==SQLITE_OK ){
    if( pAr->nArg==0 ){
      zWhere = sqlite3_mprintf("1");
    }else{
      int i;
      const char *zSep = "";
      for(i=0; i<pAr->nArg; i++){
        const char *z = pAr->azArg[i];
        zWhere = sqlite3_mprintf(
            "%z%s name = '%q' OR name BETWEEN '%q/' AND '%q0'", 
            zWhere, zSep, z, z, z
            );
        if( zWhere==0 ){
          *pRc = SQLITE_NOMEM;
          break;
        }
        zSep = " OR ";
      }
    }
  }
  *pzWhere = zWhere;
}

/*
** Implementation of .ar "lisT" command. 
*/
static int arListCommand(ShellState *p, sqlite3 *db, ArCommand *pAr){
  const char *zSql = "SELECT name FROM sqlar WHERE %s"; 
  char *zWhere = 0;
  sqlite3_stmt *pSql = 0;
  int rc;

  rc = arCheckEntries(db, pAr);
  arWhereClause(&rc, pAr, &zWhere);

  shellPreparePrintf(db, &rc, &pSql, zSql, zWhere);
  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pSql) ){
    raw_printf(p->out, "%s\n", sqlite3_column_text(pSql, 0));
  }
  return rc;
}


/*
** Implementation of .ar "eXtract" command. 
*/
static int arExtractCommand(ShellState *p, sqlite3 *db, ArCommand *pAr){
  const char *zSql1 = 
    "SELECT :1 || name, writefile(:1 || name, "
    "CASE WHEN (data AND sz>=0 AND sz!=length(data)) THEN "
    "    uncompress(data) "
    "ELSE"
    "    data "
    "END, "
    "mode, mtime) FROM sqlar WHERE (%s) AND (data IS NULL OR :2 = 0)";


  struct timespec times[2];
  sqlite3_stmt *pSql = 0;
  int rc = SQLITE_OK;
  char *zDir = 0;
  char *zWhere = 0;
  int i;

  /* If arguments are specified, check that they actually exist within
  ** the archive before proceeding. And formulate a WHERE clause to
  ** match them.  */
  rc = arCheckEntries(db, pAr);
  arWhereClause(&rc, pAr, &zWhere);

  if( rc==SQLITE_OK ){
    if( pAr->zDir ){
      zDir = sqlite3_mprintf("%s/", pAr->zDir);
    }else{
      zDir = sqlite3_mprintf("");
    }
    if( zDir==0 ) rc = SQLITE_NOMEM;
  }

  memset(times, 0, sizeof(times));
  times[0].tv_sec = time(0);

  shellPreparePrintf(db, &rc, &pSql, zSql1, zWhere);
  if( rc==SQLITE_OK ){
    sqlite3_bind_text(pSql, 1, zDir, -1, SQLITE_STATIC);

    /* Run the SELECT statement twice. The first time, writefile() is called
    ** for all archive members that should be extracted. The second time,
    ** only for the directories. This is because the timestamps for
    ** extracted directories must be reset after they are populated (as
    ** populating them changes the timestamp).  */
    for(i=0; i<2; i++){
      sqlite3_bind_int(pSql, 2, i);
      while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pSql) ){
        if( i==0 && pAr->bVerbose ){
          raw_printf(p->out, "%s\n", sqlite3_column_text(pSql, 0));
        }
      }
      shellReset(&rc, pSql);
    }
    shellFinalize(&rc, pSql);


  }











  sqlite3_free(zDir);
  sqlite3_free(zWhere);
  return rc;
}

  do_test 1.$tn.3 {
    file delete -force ar3
    file delete -force test_xyz.db
    catchcmd ":memory:" $c3
    catchcmd ":memory:" $x3
    dir_to_list ar3
  } $expected

  # This is a repeat of test 1.$tn.1, except that there is a 2 second 
  # pause between creating the archive and extracting its contents.
  # This is to test that timestamps are set correctly.
  #
  # Because it is slow, only do this for $tn==1.
  if {$tn==1} {
    do_test 1.$tn.1 {
      catchcmd test_ar.db $c1
      file delete -force ar1
      after 2000
      catchcmd test_ar.db $x1
      dir_to_list ar1
    } $expected
  }
}

finish_test



finish_test