matos/userspace/main_user.c

#include "libc.h"
#include "stdarg.h"
#include "tiny.h"

int func_help()
{
        printf("\nAvailable Commands:\n");
        printf("        help: this help\n");
        printf("        suicide: userspace self kill\n");
        printf("        syscall5: a syscall with parameters over the stack \n");
        printf("        alloc: test allocation\n");
        printf("        tiny: a tiny C-like interpreter\n");
        printf("        mmap: test mmap \n");
        return 0;
}

int func_suicide()
{
        printf("User is about to suicide\n");
        int *yolo = 0;
        *yolo     = 1;
        return 0;
}

char *initialHeap = 0;
int func_alloc()
{
        if (initialHeap == 0) {
            initialHeap = sbrk(0);
        }
        printf("Testing allocation\n");
        int allocSize     = 4096 * 2;
        char *currentHeap = sbrk(0);
        if (currentHeap - initialHeap < allocSize) {
            brk(initialHeap + allocSize);
        }
        int *allocatedData = (int *)initialHeap;
        for (unsigned int i = 0; i < allocSize / sizeof(int); i++) {
            allocatedData[i] = i;
        }
        printf("Success\nTesting malloc\n");
        uintptr_t heap = (uintptr_t)sbrk(0);

        for (int i = 0; i < 12; i++) {
            void *ptr = malloc(1 << i);
            printf("malloc size %d: 0x%p\n", (1 << i), ptr);
            if (ptr == NULL) {
                printf("Malloc failed\n");
            }
            memset(ptr, 0, 1 << i);
            free(ptr);
        }
        uintptr_t newHeap = (uintptr_t)sbrk(0);
        printf("Malloc used %dB\n", newHeap - heap);

        return 0;
}

int func_mmap() {

        char *path    = "/dev/zero";
        void *mapAddr = mmap((void *)4096, 4096, PROT_READ | PROT_WRITE, 0, path);
        printf("Zero mmaped at %p\n", mapAddr);
        int data        = *(int *)mapAddr;
        *(int *)mapAddr = data;

        return 0;
}

int main(int argc, char *argv[])
{
        (void)argc;
        (void)argv;
        char buf[64];
        printf("Shell starting... type \"help\" for help\n");
        while (1) {
                printf(">");
                if (readline(buf, sizeof(buf)))
                        continue;
                if (strcmp(buf, "help") == 0) {
                        func_help();
                        continue;
                }
                if (strcmp(buf, "suicide") == 0) {
                        func_suicide();
                        continue;
                }
                if (strcmp(buf, "syscall5") == 0) {
                        testSycall5(1, 2, 3, 4, 5);
                        continue;
                }
                if (strcmp(buf, "alloc") == 0) {
                        func_alloc();
                        continue;
                }
                if (strcmp(buf, "tiny") == 0) {
                        func_tiny();
                        continue;
                }
                if (strcmp(buf, "mmap") == 0) {
                        func_mmap();
                        continue;
                }
        }
        return 0;
}