sqlite/ext/misc/fileio.c
drh 8999798e60 Fix harmless compiler warnings in the core.
FossilOrigin-Name: 55e93f256018757e5e1cb3b10ef48abf5914e7687419eae58b00998a37061261
2017-07-11 18:11:33 +00:00

103 lines
2.5 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().
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdio.h>
/*
** 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;
FILE *in;
long nIn;
void *pBuf;
(void)(argc); /* Unused parameter */
zName = (const char*)sqlite3_value_text(argv[0]);
if( zName==0 ) return;
in = fopen(zName, "rb");
if( in==0 ) return;
fseek(in, 0, SEEK_END);
nIn = ftell(in);
rewind(in);
pBuf = sqlite3_malloc( nIn );
if( pBuf && 1==fread(pBuf, nIn, 1, in) ){
sqlite3_result_blob(context, pBuf, nIn, sqlite3_free);
}else{
sqlite3_free(pBuf);
}
fclose(in);
}
/*
** Implementation of the "writefile(X,Y)" SQL function. The argument Y
** is written into file X. The number of bytes written is returned. Or
** NULL is returned if something goes wrong, such as being unable to open
** file X for writing.
*/
static void writefileFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
FILE *out;
const char *z;
sqlite3_int64 rc;
const char *zFile;
(void)(argc); /* Unused parameter */
zFile = (const char*)sqlite3_value_text(argv[0]);
if( zFile==0 ) return;
out = fopen(zFile, "wb");
if( out==0 ) return;
z = (const char*)sqlite3_value_blob(argv[1]);
if( z==0 ){
rc = 0;
}else{
rc = fwrite(z, 1, sqlite3_value_bytes(argv[1]), out);
}
fclose(out);
sqlite3_result_int64(context, rc);
}
#ifdef _WIN32
__declspec(dllexport)
#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, 0,
readfileFunc, 0, 0);
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(db, "writefile", 2, SQLITE_UTF8, 0,
writefileFunc, 0, 0);
}
return rc;
}