On 02/04/2015 09:29, Liviu Ionescu wrote: > >> On 02 Apr 2015, at 10:56, Leon Alrae <leon.al...@imgtec.com> wrote: >> >> ... The UHI semihosting supports Argn syscall which returns single argument, >> and Argn is called multiple times to build argv (each argument can >> contain whitespaces). > > ok, I don't want to comment too much on UHI design, since I'm not familiar > with; at first sight it seems an improvement, but at second sight, from the > user perspective, with your implementation, it looks overkill; all shells I > know accept a single command line string, possibly with quotes if substrings > need to preserve the separator spaces, and internally the shells themselves > split the string into substrings and pass them to the application as (argc, > argv).
How would you pass arguments containing whitespaces via -semihosting-config cmdline without having to reinvent shell within QEMU? > > in my opinion, if UHI semihosting supports single argument Argn syscalls, > then it is the responsibility of the debugger (qemu in our case) to parse the > command line and to provide the individual substrings in the desired format, > and not ask the user to do this task manually. Couldn't the user have a wrapper around QEMU doing it for him? Leon > > the ARM semihosting case, being more primitive in this respect, requires to > run the code to split the line inside the debugged application. > > as an example, the projects generated by my GNU ARM Eclipse templates use > > https://sourceforge.net/p/micro-os-plus/iii/ci/master/tree/packages/portable/newlib.pack/src/newlib/_syscalls.c > > which, at line 419, has an __initialize_args() function. > > this is simplistic, to meet the bare metal limitations, but seems functional. > > I guess something similar, but more elaborate, can be added to qemu for UHI > semihosting. > >> I believe having just one flexible command line option in QEMU >> satisfying these two cases would be ideal. But if arg doesn't suit your >> needs then as Matthew already mentioned we probably should go for having >> cmdline and arg mutually exclusive. > > from the user point of view, I still do not see the advantages of multiple > arg=, it is easier to use quotes in a complete command line, like in any > shell; so my vote still goes to cmdline=. > > > regards, > > Liviu >
