Software Resurrection of SQLite-2.2.1
(released in Jan. 2002)

1. Introduction
2. Compile
   1. Issue 1: Compiler Support Dropped for <varargs.h>
   2. Issue 2: Name Conflict with Standard Library
3. Test
4. Critique

2. Compile

First, we download the sqlite-2002 (i.e. sqlite-2.2.1 release) sources. We will use the following folder in user's home folder to store all the files related to this exercise: $HOME/sr/sqlite/2.2.1/.

## Download source for sqlite-2.2.1
mkdir -p $HOME/sr/sqlite/2.2.1/
cd $HOME/sr/sqlite/2.2.1/
wget https://www.sqlite.org/src/tarball/61c38f3b/SQLite-61c38f3b.tar.gz
tar -zxvf SQLite-61c38f3b.tar.gz
mv SQLite-61c38f3b sqlite
      

Next, we look for instructions to compile the source code in Unix like platform. Such instructions are commonly included in a README file contained within the source distribution.

$ cat sqlite/README
This directory contains source code to

    SQLite: An SQL Database Engine in a C Library
...
   tar xzf sqlite.tar.gz    ;#  Unpack the source tree into "sqlite"
    mkdir bld                ;#  Build will occur in a sibling directory
    cd bld                   ;#  Change to the build directory
    ../sqlite/configure      ;#  Run the configure script
    make                     ;#  Run the makefile.
...
      

Recall that the compilation instructions were prepared in the year 2002 and at that time the developers of SQLite could not have seen how hardware and software platforms would change in 20 years. Still, the compilation instructions looks familiar to a reader in the year 2022. We start the compilation process as advised by the SQLite developers.

## Build sqlite-2.2.1
cd $HOME/sr/sqlite/2.2.1/
mkdir build
cd build
../sqlite/configure
        

All the above commands successfully execute to completion. In the next section, we execute the build process using the make command and get a glimpse of our first issue.

2.1 Compiler Support Dropped for <varargs.h>

The sqlite-2002 software can be built using the GCC compiler by executing the make as follows.

$ make
gcc -g -O2 -o lemon ../sqlite/tool/lemon.c
In file included from ../sqlite/tool/lemon.c:10:
/usr/lib/gcc/x86_64-linux-gnu/10/include/varargs.h:4:2: error: #error "GCC no longer implements <varargs.h>."
    4 | #error "GCC no longer implements <varargs.h>."
      |  ^~~~~
/usr/lib/gcc/x86_64-linux-gnu/10/include/varargs.h:5:2: error: #error "Revise your code to use <stdarg.h>."
    5 | #error "Revise your code to use <stdarg.h>."
      |  ^~~~~
...
../sqlite/tool/lemon.c:1096:1: error: expected declaration specifiers before ‘va_dcl’
 1096 | va_dcl
      | ^~~~~~
...
        

sqlite-2002 does not compile in gcc-10.2.1 (2021) and autoconf 2.69 (2012) because tool/lemon.c uses varargs.h which was deprecated by the gcc compiler since 4.0 (2005) release. How would we fix this compilation issue? Learners will be able to go through the experience of true self learning — which may lead to some profound insights, for example, about atomic version control commits — if they work to find a solution to this issue on their own. Clicking the "Issue 1: ..." box below will first reveal a tip which may help arrive at the solution.

## Apply patch to fix the issue about <varargs.h> (i.e. Issue 1)
mkdir -p $HOME/sr/sqlite/2.2.1/patches
cd $HOME/sr/sqlite/2.2.1/patches
wget https://abhishekdutta.org/sr/exercise/sqlite/2.2.1/patches.tar.gz
tar -zxvf patches.tar.gz
cd $HOME/sr/sqlite/2.2.1/sqlite
patch -p1 < $HOME/sr/sqlite/2.2.1/patches/1-varargs.patch
            

patching file tool/lemon.c
            

2.2 Name Conflict with Standard Library

After fixing Issue 2.1, we run the make command again to continue the build process for sqlite-2002.

## Build sqlite-2.2.1 again after fixing Issue 1
cd $HOME/sr/sqlite/2.2.1/build
../sqlite/configure
make
      

The compilation process proceeds ahead and now stops at another point with the following compilation error message.

../sqlite/src/shell.c:50:14: error: conflicting types for 'getline'
   50 | static char *getline(char *zPrompt, FILE *in){
      |              ^~~~~~~
In file included from ../sqlite/src/shell.c:19:
/usr/include/stdio.h:616:18: note: previous declaration of 'getline' was here
  616 | extern __ssize_t getline (char **__restrict __lineptr,
      |                  ^~~~~~~
make: *** [Makefile:129: sqlite] Error 1
      

The error message suggests that getline() method defined in src/shell.c:50 of sqlite-2002 source conflicts with the getline() method defined in <stdio.h> standard library.

## Apply patch to fix the issue about  (i.e. Issue 1)
## Assumption: Issue 1 (i.e. varargs issue) has already been fixed
cd $HOME/sr/sqlite/2.2.1/sqlite
patch -p1 < $HOME/sr/sqlite/2.2.1/patches/2-getline.patch
            

patching file src/shell.c
            

After fixing Issue 2, the sqlite-2002 source compiles successfully and produces the executable (e.g. sqlite) that can be used to run the SQLite database engine.

$ cd $HOME/sr/sqlite/2.2.1/build && make
...
gcc -g -O2 -DOS_UNIX=1 -DOS_WIN=0 -DHAVE_USLEEP=1 -I. -I../sqlite/src -DHAVE_READLINE=1 -I/usr/include/readline -o .libs/sqlite ../sqlite/src/shell.c  ./.libs/libsqlite.so -lreadline -Wl,--rpath -Wl,/usr/local/lib
creating sqlite