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#include "sys/syscall.h"
#include "arch/x86_64/hal/obj.h"
#include "hal/smp.h"
#include "hal/process.h"
#include "jove.h"
#include "lib/printf.h"
#include "sys/link.h"
#include "sys/message.h"
int __syscall_generic_objpath(jove_owned_obj_t *objdir, size_t payload_bytes, void *payload_data, jove_owned_obj_t **retobj)
{
size_t bytes_needed = sizeof(struct syscall_generic_objpath);
CHECK_TOOSMALL(bytes_needed, payload_bytes,
"Message too small for payload.");
struct syscall_generic_objpath *payload = payload_data;
bytes_needed += payload->pathlen << 1;
CHECK_TOOSMALL(bytes_needed, payload_bytes,
"Message too small for object path.");
errno = 0;
*retobj = objdir_getobj(objdir, payload->path, payload->pathlen);
return errno;
}
int
_syscall_handle_generic(
jove_owned_obj_t *pcb_obj,
jove_owned_obj_t *objdir,
jove_owned_obj_t *message_obj,
jove_owned_obj_t *target_obj,
struct syscall_header *header,
size_t bytes_left,
void *payload)
{
pcb_t *pcb = obj_deref(pcb_obj);
kprintf("syscall: Process %i encountered stub syscall on object %P\n", pcb_pid(pcb), header->path, header->pathlen);
return EBADOBJ;
}
static const syscall_handle_t s_syscall_handles[128] = {
[JOVE_OBJ_NONE] = NULL,
[JOVE_OBJ_UNTYPED] = _syscall_handle_untyped,
[JOVE_OBJ_OBJDIR] = _syscall_handle_objdir,
[JOVE_OBJ_PAGEDIR] = _syscall_handle_generic,
[JOVE_OBJ_PROCESSOR] = _syscall_handle_generic,
[JOVE_OBJ_PROCESS] = _syscall_handle_generic,
[JOVE_OBJ_PAGEFRAME] = _syscall_handle_generic,
[JOVE_OBJ_INITRD_FILE] = _syscall_handle_generic,
[JOVE_OBJ_FRAMEBUFFER] = _syscall_handle_generic,
[JOVE_OBJ_VIRTTERM] = _syscall_handle_vtt,
[JOVE_OBJ_MESSAGE] = _syscall_handle_generic,
[JOVE_OBJ_LINK] = _syscall_handle_generic,
};
int
syscall_handler(uintmax_t message_path_raw, uint16_t message_pathlen)
{
uint16_t *message_path = (uint16_t*)&message_path_raw;
if(message_pathlen > sizeof(uintmax_t) >> 1) {
return EBADPATH;
}
jove_owned_obj_t *pcb_obj = process_current();
pcb_t *pcb = obj_deref(pcb_obj);
jove_owned_obj_t *objdir = pcb_rootdir(pcb);
jove_owned_obj_t *message_obj = objdir_getobj(objdir, message_path, message_pathlen);
int sysret = 0;
if(message_obj == 0) {
sysret = errno;
goto release_premsg;
}
if(obj_gettype_linked(message_obj) != JOVE_OBJ_MESSAGE) {
kprintf("syscall: Process %i tried to call syscall with invalid object: %P\n", pcb_pid(pcb), message_path, message_pathlen);
sysret = EBADOBJ;
goto release_return;
}
size_t messagelen = message_len(message_obj);
void *messagedata = message_data(message_obj);
struct syscall_header *header = messagedata;
size_t bytes_needed = sizeof(struct syscall_header) + header->pathlen * 2;
if(bytes_needed > messagelen) {
//Target path exceeds message length.
kprintf("syscall: Process %i tried to call syscall with target path too big for message.\n", pcb_pid(pcb));
sysret = ETOOSMALL;
goto release_return;
}
jove_owned_obj_t *target = objdir_getobj(objdir, header->path, header->pathlen);
if(target == 0) {
//Could not find payload target in pcb rootdir.
kprintf("syscall: Process %i tried to call syscall with bad target path %P\n",
pcb_pid(pcb), header->path, header->pathlen);
sysret = errno;
goto release_return;
}
uint8_t target_type = obj_gettype(target);
size_t bytes_left = messagelen - bytes_needed;
if(target_type > 0x7F) {
sysret = _syscall_handle_arch(
pcb_obj, objdir, message_obj, target,
header, bytes_left, messagedata + bytes_needed);
}else{
syscall_handle_t call_handle = s_syscall_handles[obj_gettype(target)];
if(call_handle == NULL) {
kprintf("syscall: Process %i tried to call syscall on object %P which doesn't support syscalls!\n",
pcb_pid(pcb), header->path, header->pathlen);
sysret = EBADOBJ;
}else
sysret = call_handle(
pcb_obj, objdir, message_obj, target,
header, bytes_left, messagedata + bytes_needed);
}
obj_release(target);
release_return:
obj_release(message_obj);
release_premsg:
obj_release(objdir);
obj_release(pcb_obj);
return sysret;
}
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