/* Declarator is what introduces names into the program. */
static CTy *
declarator(CTy *basety, char **name, Node **init)
{
CTy *t;
while (tok->k == TOKCONST || tok->k == TOKVOLATILE)
next();
switch(tok->k) {
case '*':
next();
basety = mkptr(basety);
t = declarator(basety, name, init);
return t;
default:
t = directdeclarator(basety, name);
if(tok->k == '=') {
if(!init)
errorposf(&tok->pos, "unexpected initializer");
next();
*init = declinit();
} else {
if(init)
*init = 0;
}
return t;
}
}
static Node *
mkunop(SrcPos *p, int op, Node *o)
{
Node *n;
n = mknode(NUNOP, p);
n->Unop.op = op;
switch(op) {
case '&':
if(!islval(o))
errorposf(&o->pos, "& expects an lvalue");
n->type = mkptr(o->type);
break;
case '*':
if(!isptr(o->type))
errorposf(&o->pos, "cannot deref non pointer");
n->type = o->type->Ptr.subty;
break;
default:
o = ipromote(o);
n->type = o->type;
break;
}
n->Unop.operand = o;
return n;
}
/*
* Relocate PT_LOAD segements of kernel ELF image to their respective
* virtual addresses and return entry point
*/
void *
load_kernel(void * kstart)
{
#if ELFSIZE == 64
Elf64_Ehdr *eh;
Elf64_Phdr phdr[64] /* XXX */;
Elf64_Shdr shdr[64] /* XXX */;
#else
Elf32_Ehdr *eh;
Elf32_Phdr phdr[64] /* XXX */;
Elf32_Shdr shdr[64] /* XXX */;
#endif
int i, j;
void *entry_point;
vm_offset_t loadend = 0;
intptr_t lastaddr;
int symtabindex = -1;
int symstrindex = -1;
Elf_Size tmp;
#if ELFSIZE == 64
eh = (Elf64_Ehdr *)kstart;
#else
eh = (Elf32_Ehdr *)kstart;
#endif
entry_point = mkptr(eh->e_entry);
memcpy(phdr, (void *)(kstart + eh->e_phoff),
eh->e_phnum * sizeof(phdr[0]));
memcpy(shdr, (void *)(kstart + eh->e_shoff),
sizeof(*shdr) * eh->e_shnum);
if (eh->e_shnum * eh->e_shentsize != 0 && eh->e_shoff != 0) {
for (i = 0; i < eh->e_shnum; i++) {
if (shdr[i].sh_type == SHT_SYMTAB) {
/*
* XXX: check if .symtab is in PT_LOAD?
*/
if (shdr[i].sh_offset != 0 &&
shdr[i].sh_size != 0) {
symtabindex = i;
symstrindex = shdr[i].sh_link;
}
}
}
}
/*
* Copy loadable segments
*/
for (i = 0; i < eh->e_phnum; i++) {
volatile char c;
if (phdr[i].p_type != PT_LOAD)
continue;
memcpy(mkptr(phdr[i].p_vaddr),
(void*)(kstart + phdr[i].p_offset), phdr[i].p_filesz);
/* Clean space from oversized segments, eg: bss. */
if (phdr[i].p_filesz < phdr[i].p_memsz)
bzero(mkptr(phdr[i].p_vaddr + phdr[i].p_filesz),
phdr[i].p_memsz - phdr[i].p_filesz);
if (loadend < phdr[i].p_vaddr + phdr[i].p_memsz)
loadend = phdr[i].p_vaddr + phdr[i].p_memsz;
}
/* Now grab the symbol tables. */
lastaddr = (intptr_t)(int)loadend;
if (symtabindex >= 0 && symstrindex >= 0) {
tmp = SYMTAB_MAGIC;
memcpy((void *)lastaddr, &tmp, sizeof(tmp));
lastaddr += sizeof(Elf_Size);
tmp = shdr[symtabindex].sh_size +
shdr[symstrindex].sh_size + 2*sizeof(Elf_Size);
memcpy((void *)lastaddr, &tmp, sizeof(tmp));
lastaddr += sizeof(Elf_Size);
/* .symtab size */
tmp = shdr[symtabindex].sh_size;
memcpy((void *)lastaddr, &tmp, sizeof(tmp));
lastaddr += sizeof(shdr[symtabindex].sh_size);
/* .symtab data */
memcpy((void*)lastaddr,
shdr[symtabindex].sh_offset + kstart,
shdr[symtabindex].sh_size);
lastaddr += shdr[symtabindex].sh_size;
/* .strtab size */
tmp = shdr[symstrindex].sh_size;
memcpy((void *)lastaddr, &tmp, sizeof(tmp));
lastaddr += sizeof(shdr[symstrindex].sh_size);
/* .strtab data */
memcpy((void*)lastaddr,
shdr[symstrindex].sh_offset + kstart,
shdr[symstrindex].sh_size);
} else {
/* Do not take any chances */
tmp = 0;
memcpy((void *)lastaddr, &tmp, sizeof(tmp));
}
return entry_point;
}
