cosmopolitan/third_party/sqlite3/fileio.c
Justine Tunney b0df6c1fce
Implement proper time zone support
Cosmopolitan now supports 104 time zones. They're embedded inside any
binary that links the localtime() function. Doing so adds about 100kb
to the binary size. This change also gets time zones working properly
on Windows for the first time. It's not needed to have /etc/localtime
exist on Windows, since we can get this information from WIN32. We're
also now updated to the latest version of Paul Eggert's TZ library.
2024-05-04 23:06:37 -07:00

872 lines
24 KiB
C

/*
** 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 "libc/assert.h"
#include "libc/calls/calls.h"
#include "libc/calls/struct/dirent.h"
#include "libc/calls/struct/stat.h"
#include "libc/calls/struct/stat.macros.h"
#include "libc/calls/weirdtypes.h"
#include "libc/errno.h"
#include "libc/isystem/unistd.h"
#include "libc/stdio/stdio.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/at.h"
#include "libc/sysv/consts/s.h"
#include "libc/time.h"
#include "third_party/sqlite3/sqlite3ext.h"
SQLITE_EXTENSION_INIT1
/*
** Structure of the fsdir() table-valued function
*/
/* 0 1 2 3 4 5 */
#define FSDIR_SCHEMA "(name,mode,mtime,data,path HIDDEN,dir HIDDEN)"
#define FSDIR_COLUMN_NAME 0 /* Name of the file */
#define FSDIR_COLUMN_MODE 1 /* Access mode */
#define FSDIR_COLUMN_MTIME 2 /* Last modification time */
#define FSDIR_COLUMN_DATA 3 /* File content */
#define FSDIR_COLUMN_PATH 4 /* Path to top of search */
#define FSDIR_COLUMN_DIR 5 /* Path is relative to this directory */
/*
** Set the result stored by context ctx to a blob containing the
** contents of file zName. Or, leave the result unchanged (NULL)
** if the file does not exist or is unreadable.
**
** If the file exceeds the SQLite blob size limit, through an
** SQLITE_TOOBIG error.
**
** Throw an SQLITE_IOERR if there are difficulties pulling the file
** off of disk.
*/
static void readFileContents(sqlite3_context *ctx, const char *zName){
FILE *in;
sqlite3_int64 nIn;
void *pBuf;
sqlite3 *db;
int mxBlob;
in = fopen(zName, "rb");
if( in==0 ){
/* File does not exist or is unreadable. Leave the result set to NULL. */
return;
}
fseek(in, 0, SEEK_END);
nIn = ftell(in);
rewind(in);
db = sqlite3_context_db_handle(ctx);
mxBlob = sqlite3_limit(db, SQLITE_LIMIT_LENGTH, -1);
if( nIn>mxBlob ){
sqlite3_result_error_code(ctx, SQLITE_TOOBIG);
fclose(in);
return;
}
pBuf = sqlite3_malloc64( nIn ? nIn : 1 );
if( pBuf==0 ){
sqlite3_result_error_nomem(ctx);
fclose(in);
return;
}
if( nIn==(sqlite3_int64)fread(pBuf, 1, (size_t)nIn, in) ){
sqlite3_result_blob64(ctx, pBuf, nIn, sqlite3_free);
}else{
sqlite3_result_error_code(ctx, SQLITE_IOERR);
sqlite3_free(pBuf);
}
fclose(in);
}
/*
** Implementation of the "readfile(X)" SQL function. The entire content
** of the file named X is read and returned as a BLOB. NULL is returned
** if the file does not exist or is unreadable.
*/
static void readfileFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
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);
va_end(ap);
}
/*
** This function is used in place of stat(). On Windows, special handling
** is required in order for the included time to be returned as UTC. On all
** other systems, this function simply calls stat().
*/
static int fileStat(
const char *zPath,
struct stat *pStatBuf
){
return stat(zPath, pStatBuf);
}
/*
** This function is used in place of lstat(). On Windows, special handling
** is required in order for the included time to be returned as UTC. On all
** other systems, this function simply calls lstat().
*/
static int fileLinkStat(
const char *zPath,
struct stat *pStatBuf
){
#if defined(_WIN32)
int rc = lstat(zPath, pStatBuf);
if( rc==0 ) statTimesToUtc(zPath, pStatBuf);
return rc;
#else
return lstat(zPath, pStatBuf);
#endif
}
/*
** Argument zFile is the name of a file that will be created and/or written
** by SQL function writefile(). This function ensures that the directory
** zFile will be written to exists, creating it if required. The permissions
** for any path components created by this function are set in accordance
** with the current umask.
**
** If an OOM condition is encountered, SQLITE_NOMEM is returned. Otherwise,
** SQLITE_OK is returned if the directory is successfully created, or
** SQLITE_ERROR otherwise.
*/
static int makeDirectory(
const char *zFile
){
char *zCopy = sqlite3_mprintf("%s", zFile);
int rc = SQLITE_OK;
if( zCopy==0 ){
rc = SQLITE_NOMEM;
}else{
int nCopy = (int)strlen(zCopy);
int i = 1;
while( rc==SQLITE_OK ){
struct stat sStat;
int rc2;
for(; zCopy[i]!='/' && i<nCopy; i++);
if( i==nCopy ) break;
zCopy[i] = '\0';
rc2 = fileStat(zCopy, &sStat);
if( rc2!=0 ){
if( mkdir(zCopy, 0777) ) rc = SQLITE_ERROR;
}else{
if( !S_ISDIR(sStat.st_mode) ) rc = SQLITE_ERROR;
}
zCopy[i] = '/';
i++;
}
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) ){
/* The mkdir() call to create the directory failed. This might not
** be an error though - if there is already a directory at the same
** path and either the permissions already match or can be changed
** to do so using chmod(), it is not an error. */
struct stat sStat;
if( errno!=EEXIST
|| 0!=fileStat(zFile, &sStat)
|| !S_ISDIR(sStat.st_mode)
|| ((sStat.st_mode&0777)!=(mode&0777) && 0!=chmod(zFile, mode&0777))
){
return 1;
}
}
}else{
sqlite3_int64 nWrite = 0;
const char *z;
int rc = 0;
FILE *out = fopen(zFile, "wb");
if( out==0 ) return 1;
z = (const char*)sqlite3_value_blob(pData);
if( z ){
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 ){
/* Recent unix */
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 = (mode_t)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)==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);
}
}
}
/*
** SQL function: lsmode(MODE)
**
** Given a numberic st_mode from stat(), convert it into a human-readable
** text string in the style of "ls -l".
*/
static void lsModeFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
int i;
int iMode = sqlite3_value_int(argv[0]);
char z[16];
(void)argc;
if( S_ISLNK(iMode) ){
z[0] = 'l';
}else if( S_ISREG(iMode) ){
z[0] = '-';
}else if( S_ISDIR(iMode) ){
z[0] = 'd';
}else{
z[0] = '?';
}
for(i=0; i<3; i++){
int m = (iMode >> ((2-i)*3));
char *a = &z[1 + i*3];
a[0] = (m & 0x4) ? 'r' : '-';
a[1] = (m & 0x2) ? 'w' : '-';
a[2] = (m & 0x1) ? 'x' : '-';
}
z[10] = '\0';
sqlite3_result_text(context, z, -1, SQLITE_TRANSIENT);
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Cursor type for recursively iterating through a directory structure.
*/
typedef struct fsdir_cursor fsdir_cursor;
typedef struct FsdirLevel FsdirLevel;
struct FsdirLevel {
DIR *pDir; /* From opendir() */
char *zDir; /* Name of directory (nul-terminated) */
};
struct fsdir_cursor {
sqlite3_vtab_cursor base; /* Base class - must be first */
int nLvl; /* Number of entries in aLvl[] array */
int iLvl; /* Index of current entry */
FsdirLevel *aLvl; /* Hierarchy of directories being traversed */
const char *zBase;
int nBase;
struct stat sStat; /* Current lstat() results */
char *zPath; /* Path to current entry */
sqlite3_int64 iRowid; /* Current rowid */
};
typedef struct fsdir_tab fsdir_tab;
struct fsdir_tab {
sqlite3_vtab base; /* Base class - must be first */
};
/*
** Construct a new fsdir virtual table object.
*/
static int fsdirConnect(
sqlite3 *db,
void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVtab,
char **pzErr
){
fsdir_tab *pNew = 0;
int rc;
(void)pAux;
(void)argc;
(void)argv;
(void)pzErr;
rc = sqlite3_declare_vtab(db, "CREATE TABLE x" FSDIR_SCHEMA);
if( rc==SQLITE_OK ){
pNew = (fsdir_tab*)sqlite3_malloc( sizeof(*pNew) );
if( pNew==0 ) return SQLITE_NOMEM;
memset(pNew, 0, sizeof(*pNew));
sqlite3_vtab_config(db, SQLITE_VTAB_DIRECTONLY);
}
*ppVtab = (sqlite3_vtab*)pNew;
return rc;
}
/*
** This method is the destructor for fsdir vtab objects.
*/
static int fsdirDisconnect(sqlite3_vtab *pVtab){
sqlite3_free(pVtab);
return SQLITE_OK;
}
/*
** Constructor for a new fsdir_cursor object.
*/
static int fsdirOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
fsdir_cursor *pCur;
(void)p;
pCur = sqlite3_malloc( sizeof(*pCur) );
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);
}
sqlite3_free(pCur->zPath);
sqlite3_free(pCur->aLvl);
pCur->aLvl = 0;
pCur->zPath = 0;
pCur->zBase = 0;
pCur->nBase = 0;
pCur->nLvl = 0;
pCur->iLvl = -1;
pCur->iRowid = 1;
}
/*
** Destructor for an fsdir_cursor.
*/
static int fsdirClose(sqlite3_vtab_cursor *cur){
fsdir_cursor *pCur = (fsdir_cursor*)cur;
fsdirResetCursor(pCur);
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);
}
/*
** Advance an fsdir_cursor to its next row of output.
*/
static int fsdirNext(sqlite3_vtab_cursor *cur){
fsdir_cursor *pCur = (fsdir_cursor*)cur;
mode_t m = pCur->sStat.st_mode;
pCur->iRowid++;
if( S_ISDIR(m) ){
/* Descend into this directory */
int iNew = pCur->iLvl + 1;
FsdirLevel *pLvl;
if( iNew>=pCur->nLvl ){
int nNew = iNew+1;
sqlite3_int64 nByte = nNew*sizeof(FsdirLevel);
FsdirLevel *aNew = (FsdirLevel*)sqlite3_realloc64(pCur->aLvl, nByte);
if( aNew==0 ) return SQLITE_NOMEM;
memset(&aNew[pCur->nLvl], 0, sizeof(FsdirLevel)*(nNew-pCur->nLvl));
pCur->aLvl = aNew;
pCur->nLvl = nNew;
}
pCur->iLvl = iNew;
pLvl = &pCur->aLvl[iNew];
pLvl->zDir = pCur->zPath;
pCur->zPath = 0;
pLvl->pDir = opendir(pLvl->zDir);
if( pLvl->pDir==0 ){
fsdirSetErrmsg(pCur, "cannot read directory: %s", pCur->zPath);
return SQLITE_ERROR;
}
}
while( pCur->iLvl>=0 ){
FsdirLevel *pLvl = &pCur->aLvl[pCur->iLvl];
struct dirent *pEntry = readdir(pLvl->pDir);
if( pEntry ){
if( pEntry->d_name[0]=='.' ){
if( pEntry->d_name[1]=='.' && pEntry->d_name[2]=='\0' ) continue;
if( pEntry->d_name[1]=='\0' ) continue;
}
sqlite3_free(pCur->zPath);
pCur->zPath = sqlite3_mprintf("%s/%s", pLvl->zDir, pEntry->d_name);
if( pCur->zPath==0 ) return SQLITE_NOMEM;
if( fileLinkStat(pCur->zPath, &pCur->sStat) ){
fsdirSetErrmsg(pCur, "cannot stat file: %s", pCur->zPath);
return SQLITE_ERROR;
}
return SQLITE_OK;
}
closedir(pLvl->pDir);
sqlite3_free(pLvl->zDir);
pLvl->pDir = 0;
pLvl->zDir = 0;
pCur->iLvl--;
}
/* EOF */
sqlite3_free(pCur->zPath);
pCur->zPath = 0;
return SQLITE_OK;
}
/*
** Return values of columns for the row at which the series_cursor
** is currently pointing.
*/
static int fsdirColumn(
sqlite3_vtab_cursor *cur, /* The cursor */
sqlite3_context *ctx, /* First argument to sqlite3_result_...() */
int i /* Which column to return */
){
fsdir_cursor *pCur = (fsdir_cursor*)cur;
switch( i ){
case FSDIR_COLUMN_NAME: {
sqlite3_result_text(ctx, &pCur->zPath[pCur->nBase], -1, SQLITE_TRANSIENT);
break;
}
case FSDIR_COLUMN_MODE:
sqlite3_result_int64(ctx, pCur->sStat.st_mode);
break;
case FSDIR_COLUMN_MTIME:
sqlite3_result_int64(ctx, pCur->sStat.st_mtime);
break;
case FSDIR_COLUMN_DATA: {
mode_t m = pCur->sStat.st_mode;
if( S_ISDIR(m) ){
sqlite3_result_null(ctx);
}else if( S_ISLNK(m) ){
char aStatic[64];
char *aBuf = aStatic;
sqlite3_int64 nBuf = 64;
int n;
while( 1 ){
n = readlink(pCur->zPath, aBuf, nBuf);
if( n<nBuf ) break;
if( aBuf!=aStatic ) sqlite3_free(aBuf);
nBuf = nBuf*2;
aBuf = sqlite3_malloc64(nBuf);
if( aBuf==0 ){
sqlite3_result_error_nomem(ctx);
return SQLITE_NOMEM;
}
}
sqlite3_result_text(ctx, aBuf, n, SQLITE_TRANSIENT);
if( aBuf!=aStatic ) sqlite3_free(aBuf);
}else{
readFileContents(ctx, pCur->zPath);
}
}
case FSDIR_COLUMN_PATH:
default: {
/* The FSDIR_COLUMN_PATH and FSDIR_COLUMN_DIR are input parameters.
** always return their values as NULL */
break;
}
}
return SQLITE_OK;
}
/*
** Return the rowid for the current row. In this implementation, the
** first row returned is assigned rowid value 1, and each subsequent
** row a value 1 more than that of the previous.
*/
static int fsdirRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
fsdir_cursor *pCur = (fsdir_cursor*)cur;
*pRowid = pCur->iRowid;
return SQLITE_OK;
}
/*
** Return TRUE if the cursor has been moved off of the last
** row of output.
*/
static int fsdirEof(sqlite3_vtab_cursor *cur){
fsdir_cursor *pCur = (fsdir_cursor*)cur;
return (pCur->zPath==0);
}
/*
** xFilter callback.
**
** idxNum==1 PATH parameter only
** idxNum==2 Both PATH and DIR supplied
*/
static int fsdirFilter(
sqlite3_vtab_cursor *cur,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
const char *zDir = 0;
fsdir_cursor *pCur = (fsdir_cursor*)cur;
(void)idxStr;
fsdirResetCursor(pCur);
if( idxNum==0 ){
fsdirSetErrmsg(pCur, "table function fsdir requires an argument");
return SQLITE_ERROR;
}
assert( argc==idxNum && (argc==1 || argc==2) );
zDir = (const char*)sqlite3_value_text(argv[0]);
if( zDir==0 ){
fsdirSetErrmsg(pCur, "table function fsdir requires a non-NULL argument");
return SQLITE_ERROR;
}
if( argc==2 ){
pCur->zBase = (const char*)sqlite3_value_text(argv[1]);
}
if( pCur->zBase ){
pCur->nBase = (int)strlen(pCur->zBase)+1;
pCur->zPath = sqlite3_mprintf("%s/%s", pCur->zBase, zDir);
}else{
pCur->zPath = sqlite3_mprintf("%s", zDir);
}
if( pCur->zPath==0 ){
return SQLITE_NOMEM;
}
if( fileLinkStat(pCur->zPath, &pCur->sStat) ){
fsdirSetErrmsg(pCur, "cannot stat file: %s", pCur->zPath);
return SQLITE_ERROR;
}
return SQLITE_OK;
}
/*
** SQLite will invoke this method one or more times while planning a query
** that uses the generate_series virtual table. This routine needs to create
** a query plan for each invocation and compute an estimated cost for that
** plan.
**
** In this implementation idxNum is used to represent the
** query plan. idxStr is unused.
**
** The query plan is represented by values of idxNum:
**
** (1) The path value is supplied by argv[0]
** (2) Path is in argv[0] and dir is in argv[1]
*/
static int fsdirBestIndex(
sqlite3_vtab *tab,
sqlite3_index_info *pIdxInfo
){
int i; /* Loop over constraints */
int idxPath = -1; /* Index in pIdxInfo->aConstraint of PATH= */
int idxDir = -1; /* Index in pIdxInfo->aConstraint of DIR= */
int seenPath = 0; /* True if an unusable PATH= constraint is seen */
int seenDir = 0; /* True if an unusable DIR= constraint is seen */
const struct sqlite3_index_constraint *pConstraint;
(void)tab;
pConstraint = pIdxInfo->aConstraint;
for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
if( pConstraint->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
switch( pConstraint->iColumn ){
case FSDIR_COLUMN_PATH: {
if( pConstraint->usable ){
idxPath = i;
seenPath = 0;
}else if( idxPath<0 ){
seenPath = 1;
}
break;
}
case FSDIR_COLUMN_DIR: {
if( pConstraint->usable ){
idxDir = i;
seenDir = 0;
}else if( idxDir<0 ){
seenDir = 1;
}
break;
}
}
}
if( seenPath || seenDir ){
/* If input parameters are unusable, disallow this plan */
return SQLITE_CONSTRAINT;
}
if( idxPath<0 ){
pIdxInfo->idxNum = 0;
/* The pIdxInfo->estimatedCost should have been initialized to a huge
** number. Leave it unchanged. */
pIdxInfo->estimatedRows = 0x7fffffff;
}else{
pIdxInfo->aConstraintUsage[idxPath].omit = 1;
pIdxInfo->aConstraintUsage[idxPath].argvIndex = 1;
if( idxDir>=0 ){
pIdxInfo->aConstraintUsage[idxDir].omit = 1;
pIdxInfo->aConstraintUsage[idxDir].argvIndex = 2;
pIdxInfo->idxNum = 2;
pIdxInfo->estimatedCost = 10.0;
}else{
pIdxInfo->idxNum = 1;
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, /* 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 */
0, /* xSavepoint */
0, /* xRelease */
0, /* xRollbackTo */
0, /* xShadowName */
};
int rc = sqlite3_create_module(db, "fsdir", &fsdirModule, 0);
return rc;
}
#else /* SQLITE_OMIT_VIRTUALTABLE */
# define fsdirRegister(x) SQLITE_OK
#endif
int sqlite3_fileio_init(
sqlite3 *db,
char **pzErrMsg,
const sqlite3_api_routines *pApi
){
int rc = SQLITE_OK;
SQLITE_EXTENSION_INIT2(pApi);
(void)pzErrMsg; /* Unused parameter */
rc = sqlite3_create_function(db, "readfile", 1,
SQLITE_UTF8|SQLITE_DIRECTONLY, 0,
readfileFunc, 0, 0);
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(db, "writefile", -1,
SQLITE_UTF8|SQLITE_DIRECTONLY, 0,
writefileFunc, 0, 0);
}
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(db, "lsmode", 1, SQLITE_UTF8, 0,
lsModeFunc, 0, 0);
}
if( rc==SQLITE_OK ){
rc = fsdirRegister(db);
}
return rc;
}