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#include <unistd.h>
#include <fcntl.h>
#include <alloca.h>
#include "ninitfeatures.h"
static int infd=-1, outfd=-1;
static uint32t env_free=0;
#include "contrib/put_env.h"
static void die_xx(char *s) {
char *aa[3];
INIT_ARGS3(aa, "/sbin/ninit","",0);
write(2,"\nupdate: ",9);
write(2,s,str_len(s));
write(2,"\n",1);
while (1) {
execve(*aa,aa,environ); /* really panic !!! */
nano_sleep(0,800000000);
}
}
static void safe_read(void *buf, int len) {
if (read(infd,buf,len) != len) die_xx("error reading");
}
static void safe_write() {
if (write(outfd,"1",1) != 1) die_xx("error writing");
}
int main(int Argc, char **Argv) {
uint32t len,i,k;
char **argv, **env, *s;
s = Argv[0];
s[str_rchr(s, '/')] = 0;
chdir(s);
infd=open("../in",O_RDWR);
outfd=open("../out",O_RDWR|O_NONBLOCK);
fcntl(infd,F_SETFD,FD_CLOEXEC);
fcntl(outfd,F_SETFD,FD_CLOEXEC);
if (infd<0 || outfd<0) {
write(outfd,"0",1);
die_xx("pipes error");
}
write(outfd,"7",1);
safe_read(&len,sizeof(len));
argv = alloca((len+5) * sizeof(char *));
if (argv==0) die_xx("out of memory");
safe_write();
for (i=0; i<len; i++) { /* argv */
safe_read(&k, sizeof(k));
if (k) {
if ((s=alloca(k+1))==0) die_xx("out of memory");
safe_read(s,k);
s[k] = 0;
} else s = "";
argv[i] = s;
safe_write();
}
argv[i] = 0;
/* ----- environ ----- */
safe_read(&len,sizeof(len));
if (len==0) { safe_write(); goto ready; }
env_free=len+1;
if (environ==0) environ = Argv+Argc;
for (k=0; environ[k]; ) k++;
env = alloca((len+k+5) * sizeof(char *));
if (env==0) die_xx("out of memory");
byte_copy(env, (k+1)*sizeof(char *), environ);
environ=env;
safe_write();
for (i=0; i<len; i++) { /* environ */
safe_read(&k, sizeof(k));
if (k==0) environ[0] = 0;
else {
if ((s=alloca(k+1))==0) die_xx("out of memory");
safe_read(s,k);
s[k] = 0;
put_env(s);
}
safe_write();
}
ready:
safe_read(&k,sizeof(k)); /* k = "doit" */
chdir("/");
execve(*argv, argv, environ);
die_xx("PANIC");
return 1;
}
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