From 63847496f14c813a5d80efd5b7de0f1294ffe1e3 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 13 Apr 2024 16:07:11 +0200 Subject: Adding upstream version 3.45.1. Signed-off-by: Daniel Baumann --- ext/misc/sqlar.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 125 insertions(+) create mode 100644 ext/misc/sqlar.c (limited to 'ext/misc/sqlar.c') diff --git a/ext/misc/sqlar.c b/ext/misc/sqlar.c new file mode 100644 index 0000000..be079a5 --- /dev/null +++ b/ext/misc/sqlar.c @@ -0,0 +1,125 @@ +/* +** 2017-12-17 +** +** 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. +** +****************************************************************************** +** +** Utility functions sqlar_compress() and sqlar_uncompress(). Useful +** for working with sqlar archives and used by the shell tool's built-in +** sqlar support. +*/ +#include "sqlite3ext.h" +SQLITE_EXTENSION_INIT1 +#include +#include + +/* +** Implementation of the "sqlar_compress(X)" SQL function. +** +** If the type of X is SQLITE_BLOB, and compressing that blob using +** zlib utility function compress() yields a smaller blob, return the +** compressed blob. Otherwise, return a copy of X. +** +** SQLar uses the "zlib format" for compressed content. The zlib format +** contains a two-byte identification header and a four-byte checksum at +** the end. This is different from ZIP which uses the raw deflate format. +** +** Future enhancements to SQLar might add support for new compression formats. +** If so, those new formats will be identified by alternative headers in the +** compressed data. +*/ +static void sqlarCompressFunc( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + assert( argc==1 ); + if( sqlite3_value_type(argv[0])==SQLITE_BLOB ){ + const Bytef *pData = sqlite3_value_blob(argv[0]); + uLong nData = sqlite3_value_bytes(argv[0]); + uLongf nOut = compressBound(nData); + Bytef *pOut; + + pOut = (Bytef*)sqlite3_malloc(nOut); + if( pOut==0 ){ + sqlite3_result_error_nomem(context); + return; + }else{ + if( Z_OK!=compress(pOut, &nOut, pData, nData) ){ + sqlite3_result_error(context, "error in compress()", -1); + }else if( nOut