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rvinterf/etmsync/fsnew.c: cast 0 to (char *) for execl sentinel
I generally don't use NULL and use plain 0 instead, based on a "NULL
considered harmful" discussion on the classiccmp mailing list many aeons
ago (I couldn't find it, and I reason that it must have been 2005 or
earlier), but a recent complaint by a packager sent me searching, and I
found this:
https://ewontfix.com/11/
While I don't give a @#$% about "modern" systems and code-nazi tools,
I realized that passing a plain 0 as a pointer sentinel in execl is wrong
because it will break on systems where pointers are longer than the plain
int type. Again, I don't give a @#$% about the abomination of x86_64 and
the like, but if anyone ever manages to port my code to something like a
PDP-11 (16-bit int, 32-bit long and pointers), then passing a plain 0
as a function argument where a pointer is expected most definitely won't
work: if the most natural stack slot and SP alignment unit is 16 bits,
fitting an int, with longs and pointers taking up two such slots, then
the call stack will be totally wrong with a plain 0 passed for a pointer.
Casting the 0 to (char *) ought to be the most kosher solution for the
most retro systems possible.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Mon, 11 Feb 2019 00:00:19 +0000 |
| parents | e7502631a0f9 |
| children |
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The following target utilities or code components are currently buildable in this target-utils tree: compalstage For Compal phones only: a little piece of code that is fed to the original fw's bootloader via the serial download protocol provided by the latter; it re-enables the Calypso chip boot ROM and jumps to it, allowing our loadagent to be loaded in the same way as on freedom-enabled devices. helloapp Template/skeleton for building programs like loadagent and pirexplore. loadagent Loadagent is built to be loaded and run out of the Calypso internal (on-chip) RAM, and does not depend on any hardware outside of the Calypso chip itself - thus it should run unchanged on all Calypso targets. It expects to be loaded by the Calypso ROM bootloader in the UART download mode, and it reads a RAM variable left behind by the ROM code that indicates which UART has been used to perform that download - it then uses that same UART to communicate with the host, presenting an interactive command prompt. You can run loadagent "raw" by loading loadagent.srec with fc-iram, but normally it is used "behind the scenes" by fc-loadtool and fc-xram. pirexplore For Pirelli DP-L10 target only: this program is built in the same manner as loadagent (also runs out of IRAM, expects to be loaded with fc-iram, and presents an interactive command prompt on the autodetected UART), but it automatically performs some hardware (board level) initialization specific to the Pirelli, and offers additional commands for exploring the hardware features of this device. tf-breakin Here we build the payload for the tfc139 hack-utility; see ../rvinterf/lowlevel/tfc139.c for the ugly details.