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#include <u.h>
#include <libc.h>
#include <thread.h>
#include <bio.h>
#include <mach.h>
#include <ctype.h>
#include <tos.h>
#include "dat.h"
#include "fns.h"
void
initproc(void)
{
P = emallocz(sizeof(Process));
P->pid = getpid();
P->fd = newfd();
}
static void
initstack(int argc, char **argv)
{
ulong tos, sp, ap, size, i, len;
tos = STACKTOP - sizeof(Tos) * 2;
sp = tos;
size = 8;
for(i = 0; i < argc; i++)
size += strlen(argv[i]) + 5;
sp -= size;
sp &= ~7;
P->R[0] = tos;
P->R[1] = STACKTOP - 4;
P->R[13] = sp;
*(ulong *) vaddrnol(sp) = argc;
sp += 4;
ap = sp + (argc + 1) * 4;
for(i = 0; i < argc; i++) {
*(ulong *) vaddrnol(sp) = ap;
sp += 4;
len = strlen(argv[i]) + 1;
memcpy(vaddrnol(ap), argv[i], len);
ap += len;
}
*(ulong *) vaddrnol(sp) = 0;
((Tos *) vaddrnol(tos))->pid = getpid();
}
static int
loadscript(int fd, char *file, int argc, char **argv)
{
char buf[513], *p, **q, **nargv;
int rc, nargc, i;
seek(fd, 0, 0);
rc = readn(fd, buf, 512);
if(rc <= 0)
goto invalid;
close(fd);
buf[rc] = 0;
p = strchr(buf, '\n');
if(p == nil)
goto invalid;
*p = 0;
while(isspace(*--p))
*p = 0;
nargc = 0;
p = buf + 2;
while(*p) {
while(*p && isspace(*p))
p++;
nargc++;
while(*p && !isspace(*p))
p++;
}
if(nargc == 0)
goto invalid;
nargv = emallocz(sizeof(char *) * (nargc + argc));
q = nargv;
p = buf + 2;
while(*p) {
while(*p && isspace(*p))
p++;
*(p-1) = 0;
*q++ = p;
while(*p && !isspace(*p))
p++;
}
*q++ = file;
for(i = 1; i < argc; i++)
*q++ = argv[i];
rc = loadtext(*nargv, argc + nargc, nargv);
free(nargv);
return rc;
invalid:
werrstr("exec header invalid");
return -1;
}
int
loadtext(char *file, int argc, char **argv)
{
int fd, i;
Fhdr fp;
Segment *text, *data, *bss, *stack;
char buf[2];
fd = open(file, OREAD);
if(fd < 0) return -1;
if(pread(fd, buf, 2, 0) == 2 && buf[0] == '#' && buf[1] == '!')
return loadscript(fd, file, argc, argv);
seek(fd, 0, 0);
if(crackhdr(fd, &fp) == 0) {
werrstr("exec header invalid");
return -1;
}
if(fp.magic != E_MAGIC) {
werrstr("exec header invalid");
return -1;
}
freesegs();
memset(P->R, 0, sizeof(P->R));
P->CPSR = 0;
text = newseg(fp.txtaddr - fp.hdrsz, fp.txtsz + fp.hdrsz, SEGTEXT);
data = newseg(fp.dataddr, fp.datsz, SEGDATA);
bss = newseg(fp.dataddr + fp.datsz, fp.bsssz, SEGBSS);
stack = newseg(STACKTOP - STACKSIZE, STACKSIZE, SEGSTACK);
seek(fd, fp.txtoff - fp.hdrsz, 0);
if(readn(fd, text->data, fp.txtsz + fp.hdrsz) < fp.txtsz + fp.hdrsz)
sysfatal("%r");
seek(fd, fp.datoff, 0);
if(readn(fd, data->data, fp.datsz) < fp.datsz)
sysfatal("%r");
memset(bss->data, 0, bss->size);
memset(stack->data, 0, stack->size);
P->R[15] = fp.entry;
if(havesymbols && syminit(fd, &fp) < 0)
fprint(2, "initializing symbol table: %r\n");
close(fd);
for(i = 0; i < P->fd->nfds * 8; i++)
if(iscexec(P->fd, i))
close(i);
wlock(P->fd);
free(P->fd->fds);
P->fd->fds = nil;
P->fd->nfds = 0;
wunlock(P->fd);
initstack(argc, argv);
return 0;
}
void
cherrstr(char *str, ...)
{
va_list va;
va_start(va, str);
vsnprint(P->errbuf, ERRMAX, str, va);
va_end(va);
}
u32int
noteerr(u32int x, u32int y)
{
if(((int)x) >= ((int)y))
return x;
rerrstr(P->errbuf, ERRMAX);
return x;
}
Fd *
newfd(void)
{
Fd *fd;
fd = emallocz(sizeof(*fd));
incref(&fd->ref);
return fd;
}
Fd *
copyfd(Fd *old)
{
Fd *new;
rlock(old);
new = newfd();
if(old->nfds > 0) {
new->nfds = old->nfds;
new->fds = emalloc(old->nfds);
memcpy(new->fds, old->fds, old->nfds);
}
runlock(old);
return new;
}
void
fddecref(Fd *fd)
{
if(decref(&fd->ref) == 0) {
free(fd->fds);
free(fd);
}
}
int
iscexec(Fd *fd, int n)
{
int r;
r = 0;
rlock(fd);
if(n / 8 < fd->nfds)
r = (fd->fds[n / 8] & (1 << (n % 8))) != 0;
runlock(fd);
return r;
}
void
setcexec(Fd *fd, int n, int status)
{
int old;
wlock(fd);
if(n / 8 >= fd->nfds) {
if(status == 0) {
wunlock(fd);
return;
}
old = fd->nfds;
fd->nfds = (n / 8) + 1;
fd->fds = erealloc(fd->fds, fd->nfds);
memset(fd->fds + old, 0, fd->nfds - old);
}
if(status == 0)
fd->fds[n / 8] &= ~(1 << (n % 8));
else
fd->fds[n / 8] |= (1 << (n % 8));
wunlock(fd);
}
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