Add redis symlinks at the same place as the installed binaries

[vitahlin]

Related issue: https://github.com/valkey-io/valkey/issues/147

1. Add a switch to the src/Makefile to control whether or not to generate redis symlinks.

Run make install：

ls -al at /usr/local/bin:

make uninstall and ls -al:

2. Added the relevant note to the README.md, this part has yet to be polished.

[vitahlin]

I think the approach makes sense, just some minor comments

Solved the language expression problem you suggested and the space problem in Makefile. Thanks for your help.

[zuiderkwast]

One more thing: The symlinks valkey-check-rdb -> valkey-server and valkey-check-aof -> valkey-server work by conditional code in server.c looking for the exec name, i.e. which symlink was used for starting it. Please also check that it works for redis-check-rdb etc.

Code in server.c:

    /* Check if we need to start in redis-check-rdb/aof mode. We just execute
     * the program main. However the program is part of the Redis executable
     * so that we can easily execute an RDB check on loading errors. */
    if (strstr(exec_name,"valkey-check-rdb") != NULL)
        redis_check_rdb_main(argc,argv,NULL);
    else if (strstr(exec_name,"valkey-check-aof") != NULL)
        redis_check_aof_main(argc,argv);

[vitahlin]

One more thing: The symlinks valkey-check-rdb -> valkey-server and valkey-check-aof -> valkey-server work by conditional code in server.c looking for the exec name, i.e. which symlink was used for starting it. Please also check that it works for redis-check-rdb etc.

Code in server.c:

    /* Check if we need to start in redis-check-rdb/aof mode. We just execute
     * the program main. However the program is part of the Redis executable
     * so that we can easily execute an RDB check on loading errors. */
    if (strstr(exec_name,"valkey-check-rdb") != NULL)
        redis_check_rdb_main(argc,argv,NULL);
    else if (strstr(exec_name,"valkey-check-aof") != NULL)
        redis_check_aof_main(argc,argv);

I will test it next.

[vitahlin]

My first PR that wasn't about typo. Thank you for your patience and help, have a nice day. 😀

[zuiderkwast]

Thanks @vitahlin! I edited the top comment to match what was finally implemented.

[furai]

For me this change causes issues when using TLS. When I switch off symlinks for redis then installation fails cause it can't find libhiredis_ssl.a. Could this implementation be revisited?

[zuiderkwast]

@furai Yes, of course we can revise it. Why is libhiredis_ssl.a affected by this?

[furai]

I haven't had time to dig into it. What I'm doing is pretty simple, e.g.:

 make BUILD_TLS=yes USE_SYSTEMD=yes 
 make PREFIX=custom/usr USE_REDIS_SYMLINKS=no install

And then it fails with error because it can't find the aforementioned file. I was building from prepackaged version 7.2.5 available here on github.