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Nable wrote:You won't believe but read http://wiki.osdev.org/C%2B%2B_Bare_Bones

Nable wrote:Erm.. As for me, the article contains enough code for building some small testing environment.

Tosi wrote:This isn't a place to ask for code.
Either code it yourself, or find some existing implementation and port it.
Writing to screen is exceedingly easy if you stick to the basics.
Remember, if you can do it in C, you can do it in C++ with little to no change to the code.

platform wrote:I need a little bit more and it has to be faster, because if the test fails, I am going to change my idea of how the kernel should be.

bluemoon wrote:

platform wrote:I need a little bit more and it has to be faster, because if the test fails, I am going to change my idea of how the kernel should be.

No, you don't have to implement it to test your idea, you're not writing linux huh?
For complex problem like kernel design, you test your idea by running thru the design documents and diagrams.

$ cat testapp/main.c 
#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main ( int argc, char *argv[] ) {
    int pid = (int)getpid();
    for (int i=0;i<pid+3;i++) {
        printf ("  PID[%d]: Hello again! counter=%d\n", pid, i);
        usleep((useconds_t) (1000000));
    }
    return (int)0xBADC0DE0+ (int)pid;
}

SLOC	Directory	SLOC-by-Language (Sorted)
4958    kernel          ansic=2205,asm=1354,cpp=1253,sh=146
679     boot            asm=679
430     drivers         ansic=288,sh=142
338     libgloss        asm=226,sh=112
143     mkinitrd        cpp=143
124     testapp         sh=112,ansic=12
92      mkdiskimage     cpp=92

platform wrote:By the way, I have tested many times the C++ Bare bones and:
loader.s:18: Error: junk at end of line, first unrecognized character is `,'

bluemoon wrote:The C++ barebone tutorial is about writing kernel in C++, not about running C++ program with your kernel.
In order to run user-space application (in particular with C++ runtime, and a reasonable set of syscall), the kernel itself already require lots of features.

I consider my kernel a very minimum just to run a C program:

Code: Select all

$ cat testapp/main.c 
#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main ( int argc, char *argv[] ) {
    int pid = (int)getpid();
    for (int i=0;i<pid+3;i++) {
        printf ("  PID[%d]: Hello again! counter=%d\n", pid, i);
        usleep((useconds_t) (1000000));
    }
    return (int)0xBADC0DE0+ (int)pid;
}

SLOC	Directory	SLOC-by-Language (Sorted)
4958    kernel          ansic=2205,asm=1354,cpp=1253,sh=146
679     boot            asm=679
430     drivers         ansic=288,sh=142
338     libgloss        asm=226,sh=112
143     mkinitrd        cpp=143
124     testapp         sh=112,ansic=12
92      mkdiskimage     cpp=92

This requires over 5000 lines of code, which is comparable to the scale of a 3D engine with scene management and particle dynamics.
If you are having trouble building the barebone, I very doubt looking into codebase of such amount would provide any reasonable insight.

A more productive way is that you go thru the tutorials and ask questions.

platform wrote:By the way, I have tested many times the C++ Bare bones and:
loader.s:18: Error: junk at end of line, first unrecognized character is `,'

I copy&paste the code and it assemble without error, have you verify that your browser do not insert junk when copy&paste?
Try type it by hand, you are not suggested to copy&paste anyway.
(Hint: check loader.s line 18 to see any hidden character, then delete the whole line and type it by hand)

platform wrote:So, what I am supposed to do? That means that you, user "bluemoon", has reason and I have typed badly the code?