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#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
extern char **environ;
//
void hello()
{
// ascci art: http://patorjk.com/software/taag/#p=testall&f=Cards&t=Fool%20OS
puts(
" ______ __ ____ _____ \n"
" / ____/___ ____ / / / __ \\/ ___/ \n"
" / /_ / __ \\/ __ \\/ / / / / /\\__ \\ \n"
" / __/ / /_/ / /_/ / / / /_/ /___/ / \n"
" /_/ \\____/\\____/_/ \\____//____/ \n"
" \n"
"Welcome to FoolShell v0.4 (Compiled on " __DATE__ " at " __TIME__ "\n"
"------------------------------------------------------------------\n\n"
"Please type 'help' anytime, to show shell \"built-ins\" or execute \n"
"user programms that are in you $PATH directory by simply typing \n"
"their filenames. You can get additional information for many commands\n"
"by invking them with the --help or -h flag (e.g. ls --help) \n"
);
printf("Your $PATH is currently set to: %s\n\n",getenv("PATH"));
}
void prompt()
{
printf("%s%s",getenv("PWD"),getenv("PS1"));
}
int main(int argc, char **argv)
{
bool silent=false;
for(int i=0;i<argc;i++)
{
if(!strcmp(argv[i],"--silent"))silent=true;
}
if(!silent)hello();
char *buf=malloc(256);
while(1)
{
prompt();
fgets(buf,255,stdin);
buf[strlen(buf)-1]=0; // remove \n
process(buf);
}
return 0;
}
char **tokenize(char *buf)
{
char **token;
token=malloc(10*sizeof(char*));
int l=strlen(buf);
int i;
int c=0;
for(i=0;i<l;i++)
{
// init space for next token
token[c]=malloc(256);
//skip all the whitespace
while(buf[i]==' '&&i<l)i++;
if(i==l)break;
//get token
int t=0;
while(buf[i]!=' '&&i<l)
{
token[c][t]=buf[i];
t++;
i++;
}
token[c][t]=0;
// printf("token %i : <%s>\n",c, token[c]);
c++;
token[c]=NULL;
}
return token;
}
int process(char *buf)
{
char **token=tokenize(buf);
char *command=token[0];
// puts(command);
// copied from trottelshell
if(!strcmp(command,"help"))
{
puts("foolshell: supported built-in commands: 'help', 'echo [string]', 'malloc [bytes]', 'free [address]', 'getenv [var]', 'putenv/setenv [var] [val]', 'env' 'cd [dir]'");
}
else if(!strcmp(command,"cd"))
{
char *dir=getenv("PWD");
char buf[256];
if(token[1][0]!='/')
{
sprintf(buf,"%s%s%s",dir,dir[0]=='/'&&dir[1]==0?"":"/",token[1]);
}
else
{
sprintf(buf,"%s",token[1]);
}
char token[10];
//adjust pwd (resolve '..' and '.')
//// printf("adjusting pwd: '%s'\n",buf);
int left=1;
int right=0;
do{
int t=0;
do
{
right++;
token[t]=buf[right];
t++;
}
while(buf[right]!=0&&buf[right]!='/');
token[t-1]=0;
// printf("path token: '%s'\n",token);
if(!strcmp(token,".."))
{
left--;
while(buf[left]!='/')left--;
}
else if(!strcmp(token,"."))
{
}
else
{
int i=0;
if(left!=1)buf[left++]='/';
do{buf[left++]=token[i++];}while(token[i]!=0);
}
}while(buf[right]!=0);
buf[left]=0;
// printf("adjusted: '%s'\n",buf);
setenv("PWD",buf,1);
}
else if(!strcmp(command,"echo"))
{
printf("\"%s\"\n",token[1]);
}
else if(!strcmp(command,"malloc"))
{
uint8_t *mall=malloc(atoi(token[1]));
printf("allocated %d bytes at 0x%08X (%i).\n",atoi(token[1]),mall,mall);
}
else if(!strcmp(command,"free"))
{
free(atoi(token[1]));
printf("called free(0x%08X).\n",atoi(token[1]));
}
else if(!strcmp(command,"getenv"))
{
printf("(0x%08X) get: '%s' = '%s'(0x%08X) \n",environ,token[1],getenv(token[1]),getenv(token[1]));
}
else if(!strcmp(command,"putenv")||!strcmp(command,"setenv"))
{
char buf[256];
sprintf(buf,"%s=%s",token[1],token[2]);
putenv(buf);
printf("(0x%08X) set: '%s' = '%s' \n",environ,token[1],getenv(token[1]));
}
else if(!strcmp(command,"env"))
{
int i=0;
printf("env: 0x%08X\n",environ);
while(environ[i]!=NULL)
{
printf("envvar %s (0x%08X)\n" ,environ[i],environ[i]);
i++;
}
}
else
{
char buf[256];
sprintf(buf,"%s/%s",getenv("PATH"),token[0]);
asm("mov $0x05bff,%esp"); // set stack pointer
execve(buf,token,environ);
asm("mov $0x07000,%esp"); // set stack pointer
puts("foolshell: command not found");
asm("mov $0x05bff,%esp"); // set stack pointer
static char *argv[]={"shell","--silent",NULL};
execve("/bin/foolshell",argv,environ); // start shell
}
return 0;
}
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