wiki:Packages/SQLite

Version 16 (modified by C Rempel, on Jun 25, 2012 at 8:44:14 PM) (diff)

/* Testing Ideas = */

SQLite

SQLite was originally designed to be an embedded database for on-board guided missile destroyers, for the US Navy The Definitive Guide to Sqlite By Michael Owens. Unlike many database program, SQLite is designed to be an itegral part of the embedded system. SQLite doesn't use interprocess communication, which makes it much faster than a database system that does.

Some quick notes

For a developer that might be interested in porting SQLite to RTEMS...

To build SQLite from the development repository, you need TCL and fossil. TCL is part of the SQLite build system, while fossil is another version control system.

~$ sudo apt-get install tcl8.5 fossil

SQLite uses fossil for their development branch, so if you use their development branch, you have some steps to go through:

First, check out a "fossil" which is a single file with all the information

~/sqlite$ fossil clone http://www.sqlite.org/cgi/src/dir trunk.fossil

Second, make and navigate into an sqlite directory:

~$ mkdir sqlite ~$ cd sqlite

Third, open the fossil file

~/sqlite$ fossil open ../trunk.fossil

Fourth, archaive the sqlite folder (so you have an old copy to fall back on)...

~/sqlite$ cd .. ~$ tar -acf sqlite.fossil.tar.bz2 sqlite

DO NOT close the fossil file! It will remove manifest.uuid and not compile!

Makefile.sqlite

Just figured out how to get SQLite to compile!

First, install the rtems-graphics-toolkit/mman_kit, so that SQLite can use shared memory, (shm).

Second, comment out the references to popen and pclose in rtems-addon-packages/sqlite/src/shell.c

Third, copy the Makefile below into rtems-addon-packages/RTEMS_Makefiles/Makefile.sqlite

#
# Configure/build/install the sqlite library
# note: comment out the references to popen and pclose in src/shell.c
# until a reasonable substitution can be found

include ../RTEMS_Makefiles/Makefile.common

all:
	CFLAGS='-DPROT_READ=0x01' \
	CFLAGS='-DPROT_WRITE=0x02' \
	CFLAGS='-DMAP_SHARED=0x001' \
	CFLAGS='-DSQLITE_OMIT_ALTERTABLE=2 ' \
	LDFLAGS='-lmmap_kit' \
	../sqlite/configure \
		--prefix=$(exec_prefix) \
		--build=i686-linux-gnu \
		--host=i386-rtems4.11 \
		--disable-largefile \
		--enable-cross-thread-connections \
		--disable-tcl \
		--disable-readline \
		--disable-amalgamation \
		--libdir=$(exec_prefix)/$(RTEMS_BSP)/lib \
		--includedir=$(exec_prefix)/$(RTEMS_BSP)/lib/include
	make 
	make install
}}}=  Flags Explained  =

PROT_READ, PROT_WRITE, and MAP_SHARED all relate to shared memory support, and they're definitions can be found in the FreeBSD sys/mman.h header.  The SQLite omit altertable was defined to enhance security and reduce code size.  The mmap_kit was linked to provide definitions for mmap and munmap for shared memory support.
=  Configurations Explained  =

The build had to be defined because the June 2012 sqlite developer repository couldn't recognize the build of my laptop.  As RTEMS is mostly on 32-bit (or smaller) architectures, I disabled largfile support.  Cross-thread connections looked useful for RTEMS, so I put it in there, I disabled tcl and readline support to reduce dependencies, and disabled amalgamation to isolate porting issues.
=  Testing Ideas  =

Originally I thought it would be necessary to define a src/os_rtems.c because of issues with shared memory support, but as that is no longer an issue, I would suggest using the network-demos as a code-base to copy and the [http://www.sqlite.org/quickstart.html SQLite quickstart] guide as guideline for the database demo.

The major porting issue left for a completely satisfactory build is: either declaring popen and pclose, or replacing them using the threading counter-parts may be more desirable in the long run.  (After all SQLite builds okay once they are commented out).  C Rempel is currently working on porting the OpenLDAP testsuite to RTEMS, so if this looks interesting...

Haven't gotten any farther, but I thought that was rather interesting...
=  References  =