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#include <errno.h>
extern char ** environ;
#ifdef L_execl
int
execl(fname, arg0)
char * fname, *arg0;
{
return execve(fname, &arg0, environ);
}
#endif
#ifdef L_execv
int
execv(fname, argv)
char * fname, **argv;
{
return execve(fname, argv, environ);
}
#endif
#ifdef L_execle
int
execle(fname, arg0)
char *fname, *arg0;
{
char ** envp = &arg0;
while(*envp) envp++;
return execve(fname, &arg0, envp+1);
}
#endif
#ifdef L_execve
int
execve(fname, argv, envp)
char * fname;
char ** argv;
char ** envp;
{
char **p;
int argv_len=0, argv_count=0;
int envp_len=0, envp_count=0;
int stack_bytes;
unsigned short * pip;
char * pcp, * stk_ptr, *baseoff;
int rv;
/* How much space for argv */
for(p=argv; p && *p && argv_len >= 0; p++)
{
argv_count++; argv_len += strlen(*p)+1;
}
/* How much space for envp */
for(p=envp; p && *p && envp_len >= 0; p++)
{
envp_count++; envp_len += strlen(*p)+1;
}
/* tot it all up */
stack_bytes = 2 /* argc */
+ argv_count * 2 + 2 /* argv */
+ argv_len
+ envp_count * 2 + 2 /* envp */
+ envp_len;
/* Allocate it */
if( argv_len < 0 || envp_len < 0 || stack_bytes <= 0
|| (int)(stk_ptr = (char*)sbrk(stack_bytes)) == -1)
{
errno = ENOMEM;
return -1;
}
/* Sanity check
printf("Argv = (%d,%d), Envp=(%d,%d), stack=%d\n",
argv_count, argv_len, envp_count, envp_len, stack_bytes);
*/
/* Now copy in the strings */
pip=(unsigned short *) stk_ptr;
pcp=stk_ptr+2*(1+argv_count+1+envp_count+1);
/* baseoff = stk_ptr + stack_bytes; */
baseoff = stk_ptr;
*pip++ = argv_count;
for(p=argv; p && *p; p++)
{
int l;
*pip++ = pcp-baseoff;
l = strlen(*p)+1;
memcpy(pcp, *p, l);
pcp += l;
}
*pip++ = 0;
for(p=envp; p && *p; p++)
{
int l;
*pip++ = pcp-baseoff;
l = strlen(*p)+1;
memcpy(pcp, *p, l);
pcp += l;
}
*pip++ = 0;
rv = __exec(fname, stk_ptr, stack_bytes);
/* FIXME: This will probably have to interpret '#!' style exe's */
sbrk(-stack_bytes);
return rv;
}
#endif
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