/*
* Verify redzones.
* This function is called on free() and realloc().
*/
void
redzone_check(caddr_t naddr)
{
struct stack ast, fst;
caddr_t haddr, faddr;
u_int ncorruptions;
u_long nsize;
int i;
haddr = naddr - REDZONE_HSIZE;
bcopy(haddr, &ast, sizeof(ast));
haddr += sizeof(ast);
bcopy(haddr, &nsize, sizeof(nsize));
haddr += sizeof(nsize);
atomic_subtract_long(&redzone_extra_mem,
redzone_size_ntor(nsize) - nsize);
/* Look for buffer underflow. */
ncorruptions = 0;
for (i = 0; i < REDZONE_CHSIZE; i++, haddr++) {
if (*(u_char *)haddr != 0x42)
ncorruptions++;
}
if (ncorruptions > 0) {
printf("REDZONE: Buffer underflow detected. %u byte%s "
"corrupted before %p (%lu bytes allocated).\n",
ncorruptions, ncorruptions == 1 ? "" : "s", naddr, nsize);
printf("Allocation backtrace:\n");
stack_print_ddb(&ast);
printf("Free backtrace:\n");
stack_save(&fst);
stack_print_ddb(&fst);
if (redzone_panic)
panic("Stopping here.");
}
faddr = naddr + nsize;
/* Look for buffer overflow. */
ncorruptions = 0;
for (i = 0; i < REDZONE_CFSIZE; i++, faddr++) {
if (*(u_char *)faddr != 0x42)
ncorruptions++;
}
if (ncorruptions > 0) {
printf("REDZONE: Buffer overflow detected. %u byte%s corrupted "
"after %p (%lu bytes allocated).\n", ncorruptions,
ncorruptions == 1 ? "" : "s", naddr + nsize, nsize);
printf("Allocation backtrace:\n");
stack_print_ddb(&ast);
printf("Free backtrace:\n");
stack_save(&fst);
stack_print_ddb(&fst);
if (redzone_panic)
panic("Stopping here.");
}
}
/*
* Set redzones and remember allocation backtrace.
*/
void *
redzone_setup(caddr_t raddr, u_long nsize)
{
struct stack st;
caddr_t haddr, faddr;
atomic_add_long(&redzone_extra_mem, redzone_size_ntor(nsize) - nsize);
haddr = raddr + redzone_roundup(nsize) - REDZONE_HSIZE;
faddr = haddr + REDZONE_HSIZE + nsize;
/* Redzone header. */
stack_save(&st);
bcopy(&st, haddr, sizeof(st));
haddr += sizeof(st);
bcopy(&nsize, haddr, sizeof(nsize));
haddr += sizeof(nsize);
memset(haddr, 0x42, REDZONE_CHSIZE);
haddr += REDZONE_CHSIZE;
/* Redzone footer. */
memset(faddr, 0x42, REDZONE_CFSIZE);
return (haddr);
}
void *khttpd_malloc(size_t size)
{
#ifdef KHTTPD_TRACE_MALLOC
struct stack st;
#endif
void *mem;
mem = malloc(size, M_KHTTPD, M_WAITOK);
#ifdef KHTTPD_TRACE_MALLOC
TR2("alloc %p %#lx", mem, size);
stack_save(&st);
CTRSTACK(KTR_GEN, &st, 8, 0);
#endif
return (mem);
}
char *khttpd_strdup(const char *str)
{
#ifdef KHTTPD_TRACE_MALLOC
struct stack st;
#endif
char *newstr;
newstr = strdup(str, M_KHTTPD);
#ifdef KHTTPD_TRACE_MALLOC
TR2("alloc %p %#lx", newstr, strlen(newstr) + 1);
stack_save(&st);
CTRSTACK(KTR_GEN, &st, 8, 0);
#endif
return (newstr);
}
int main()
{
struct stack_t* stos = stack_create(10);
stack_push(stos, 10);
stack_push(stos, 20);
stack_push(stos, 30);
stack_print(stos);
printf("%d\n", stack_pop(stos)); // 30
stack_print(stos); // 20 10
stack_save(stos, "stos.bin");
stack_clear(stos);
stack_load(stos, "stos.bin");
stack_push(stos, 25);
stack_print(stos);
stack_free(stos);
return 0;
}
void jq_start(jq_state *jq, jv input, int flags) {
jv_nomem_handler(jq->nomem_handler, jq->nomem_handler_data);
jq_reset(jq);
struct closure top = {jq->bc, -1};
struct frame* top_frame = frame_push(jq, top, 0, 0);
top_frame->retdata = 0;
top_frame->retaddr = 0;
stack_push(jq, input);
stack_save(jq, jq->bc->code, stack_get_pos(jq));
if (flags & JQ_DEBUG_TRACE) {
jq->debug_trace_enabled = 1;
} else {
jq->debug_trace_enabled = 0;
}
jq->initial_execution = 1;
}
void
kdb_backtrace(void)
{
if (kdb_dbbe != NULL && kdb_dbbe->dbbe_trace != NULL) {
printf("KDB: stack backtrace:\n");
kdb_dbbe->dbbe_trace();
}
#ifdef STACK
else {
struct stack st;
printf("KDB: stack backtrace:\n");
stack_save(&st);
stack_print_ddb(&st);
}
#endif
}
void *khttpd_realloc(void *mem, size_t size)
{
#ifdef KHTTPD_TRACE_MALLOC
struct stack st;
#endif
void *newmem;
newmem = realloc(mem, size, M_KHTTPD, M_WAITOK);
#ifdef KHTTPD_TRACE_MALLOC
TR1("free %p", mem);
TR2("alloc %p %#lx", newmem, size);
stack_save(&st);
CTRSTACK(KTR_GEN, &st, 8, 0);
#endif
return (newmem);
}
static int
xendebug_filter(void *arg)
{
#if defined(STACK) && defined(DDB)
struct stack st;
struct trapframe *frame;
frame = arg;
stack_zero(&st);
stack_save(&st);
mtx_lock_spin(&lock);
sbuf_clear(buf);
xc_printf("Printing stack trace vCPU%d\n", PCPU_GET(vcpu_id));
stack_sbuf_print_ddb(buf, &st);
sbuf_finish(buf);
mtx_unlock_spin(&lock);
#endif
return (FILTER_HANDLED);
}
void jq_init(struct bytecode* bc, jv input, jq_state **jq, int flags) {
jq_state *new_jq;
new_jq = jv_mem_alloc(sizeof(*new_jq));
memset(new_jq, 0, sizeof(*new_jq));
new_jq->path = jv_null();
forkable_stack_init(&new_jq->data_stk, sizeof(data_stk_elem) * 100);
forkable_stack_init(&new_jq->frame_stk, 1024);
forkable_stack_init(&new_jq->fork_stk, 1024);
stack_push(new_jq, input);
struct closure top = {bc, -1};
frame_push(&new_jq->frame_stk, top, 0);
stack_save(new_jq, bc->code);
stack_switch(new_jq);
if (flags & JQ_DEBUG_TRACE) {
new_jq->debug_trace_enabled = 1;
} else {
new_jq->debug_trace_enabled = 0;
}
new_jq->initial_execution = 1;
*jq = new_jq;
}
jv jq_next(jq_state *jq) {
jv cfunc_input[MAX_CFUNCTION_ARGS];
jv_nomem_handler(jq->nomem_handler, jq->nomem_handler_data);
uint16_t* pc = stack_restore(jq);
assert(pc);
int backtracking = !jq->initial_execution;
jq->initial_execution = 0;
while (1) {
uint16_t opcode = *pc;
if (jq->debug_trace_enabled) {
dump_operation(frame_current(jq)->bc, pc);
printf("\t");
const struct opcode_description* opdesc = opcode_describe(opcode);
stack_ptr param = 0;
if (!backtracking) {
int stack_in = opdesc->stack_in;
if (stack_in == -1) stack_in = pc[1];
int i;
for (i=0; i<stack_in; i++) {
if (i == 0) {
param = jq->stk_top;
} else {
printf(" | ");
param = *stack_block_next(&jq->stk, param);
}
if (!param) break;
jv_dump(jv_copy(*(jv*)stack_block(&jq->stk, param)), 0);
//printf("<%d>", jv_get_refcnt(param->val));
//printf(" -- ");
//jv_dump(jv_copy(jq->path), 0);
}
} else {
printf("\t<backtracking>");
}
printf("\n");
}
if (backtracking) {
opcode = ON_BACKTRACK(opcode);
backtracking = 0;
}
pc++;
switch (opcode) {
default: assert(0 && "invalid instruction");
case LOADK: {
jv v = jv_array_get(jv_copy(frame_current(jq)->bc->constants), *pc++);
assert(jv_is_valid(v));
jv_free(stack_pop(jq));
stack_push(jq, v);
break;
}
case DUP: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
break;
}
case DUP2: {
jv keep = stack_pop(jq);
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, keep);
stack_push(jq, v);
break;
}
case SUBEXP_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
jq->subexp_nest++;
break;
}
case SUBEXP_END: {
assert(jq->subexp_nest > 0);
jq->subexp_nest--;
jv a = stack_pop(jq);
jv b = stack_pop(jq);
stack_push(jq, a);
stack_push(jq, b);
break;
}
case POP: {
jv_free(stack_pop(jq));
break;
}
case APPEND: {
jv v = stack_pop(jq);
uint16_t level = *pc++;
uint16_t vidx = *pc++;
jv* var = frame_local_var(jq, vidx, level);
assert(jv_get_kind(*var) == JV_KIND_ARRAY);
*var = jv_array_append(*var, v);
break;
}
case INSERT: {
jv stktop = stack_pop(jq);
jv v = stack_pop(jq);
jv k = stack_pop(jq);
jv objv = stack_pop(jq);
assert(jv_get_kind(objv) == JV_KIND_OBJECT);
if (jv_get_kind(k) == JV_KIND_STRING) {
stack_push(jq, jv_object_set(objv, k, v));
stack_push(jq, stktop);
} else {
print_error(jq, jv_invalid_with_msg(jv_string_fmt("Cannot use %s as object key",
jv_kind_name(jv_get_kind(k)))));
jv_free(stktop);
jv_free(v);
jv_free(k);
jv_free(objv);
goto do_backtrack;
}
break;
}
case ON_BACKTRACK(RANGE):
case RANGE: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
jv max = stack_pop(jq);
if (jv_get_kind(*var) != JV_KIND_NUMBER ||
jv_get_kind(max) != JV_KIND_NUMBER) {
print_error(jq, jv_invalid_with_msg(jv_string_fmt("Range bounds must be numeric")));
jv_free(max);
goto do_backtrack;
} else if (jv_number_value(jv_copy(*var)) >= jv_number_value(jv_copy(max))) {
/* finished iterating */
goto do_backtrack;
} else {
jv curr = jv_copy(*var);
*var = jv_number(jv_number_value(*var) + 1);
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, jv_copy(max));
stack_save(jq, pc - 3, spos);
stack_push(jq, curr);
}
break;
}
// FIXME: loadv/storev may do too much copying/freeing
case LOADV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(*var), 0);
printf("\n");
}
jv_free(stack_pop(jq));
stack_push(jq, jv_copy(*var));
break;
}
// Does a load but replaces the variable with null
case LOADVN: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(*var), 0);
printf("\n");
}
jv_free(stack_pop(jq));
stack_push(jq, *var);
*var = jv_null();
break;
}
case STOREV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
jv val = stack_pop(jq);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(val), 0);
printf("\n");
}
jv_free(*var);
*var = val;
break;
}
case PATH_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jq->path);
stack_save(jq, pc - 1, stack_get_pos(jq));
stack_push(jq, jv_number(jq->subexp_nest));
stack_push(jq, v);
jq->path = jv_array();
jq->subexp_nest = 0;
break;
}
case PATH_END: {
jv v = stack_pop(jq);
jv_free(v); // discard value, only keep path
int old_subexp_nest = (int)jv_number_value(stack_pop(jq));
jv path = jq->path;
jq->path = stack_pop(jq);
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, jv_copy(path));
stack_save(jq, pc - 1, spos);
stack_push(jq, path);
jq->subexp_nest = old_subexp_nest;
break;
}
case ON_BACKTRACK(PATH_BEGIN):
case ON_BACKTRACK(PATH_END): {
jv_free(jq->path);
jq->path = stack_pop(jq);
goto do_backtrack;
}
case INDEX:
case INDEX_OPT: {
jv t = stack_pop(jq);
jv k = stack_pop(jq);
path_append(jq, jv_copy(k));
jv v = jv_get(t, k);
if (jv_is_valid(v)) {
stack_push(jq, v);
} else {
if (opcode == INDEX)
print_error(jq, v);
else
jv_free(v);
goto do_backtrack;
}
break;
}
case JUMP: {
uint16_t offset = *pc++;
pc += offset;
break;
}
case JUMP_F: {
uint16_t offset = *pc++;
jv t = stack_pop(jq);
jv_kind kind = jv_get_kind(t);
if (kind == JV_KIND_FALSE || kind == JV_KIND_NULL) {
pc += offset;
}
stack_push(jq, t); // FIXME do this better
break;
}
case EACH:
case EACH_OPT:
stack_push(jq, jv_number(-1));
// fallthrough
case ON_BACKTRACK(EACH):
case ON_BACKTRACK(EACH_OPT): {
int idx = jv_number_value(stack_pop(jq));
jv container = stack_pop(jq);
int keep_going, is_last = 0;
jv key, value;
if (jv_get_kind(container) == JV_KIND_ARRAY) {
if (opcode == EACH || opcode == EACH_OPT) idx = 0;
else idx = idx + 1;
int len = jv_array_length(jv_copy(container));
keep_going = idx < len;
is_last = idx == len - 1;
if (keep_going) {
key = jv_number(idx);
value = jv_array_get(jv_copy(container), idx);
}
} else if (jv_get_kind(container) == JV_KIND_OBJECT) {
if (opcode == EACH || opcode == EACH_OPT) idx = jv_object_iter(container);
else idx = jv_object_iter_next(container, idx);
keep_going = jv_object_iter_valid(container, idx);
if (keep_going) {
key = jv_object_iter_key(container, idx);
value = jv_object_iter_value(container, idx);
}
} else {
assert(opcode == EACH || opcode == EACH_OPT);
if (opcode == EACH) {
print_error(jq,
jv_invalid_with_msg(jv_string_fmt("Cannot iterate over %s",
jv_kind_name(jv_get_kind(container)))));
}
keep_going = 0;
}
if (!keep_going) {
jv_free(container);
goto do_backtrack;
} else if (is_last) {
// we don't need to make a backtrack point
jv_free(container);
path_append(jq, key);
stack_push(jq, value);
} else {
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, container);
stack_push(jq, jv_number(idx));
stack_save(jq, pc - 1, spos);
path_append(jq, key);
stack_push(jq, value);
}
break;
}
do_backtrack:
case BACKTRACK: {
pc = stack_restore(jq);
if (!pc) {
return jv_invalid();
}
backtracking = 1;
break;
}
case FORK: {
stack_save(jq, pc - 1, stack_get_pos(jq));
pc++; // skip offset this time
break;
}
case ON_BACKTRACK(FORK): {
uint16_t offset = *pc++;
pc += offset;
break;
}
case CALL_BUILTIN: {
int nargs = *pc++;
jv top = stack_pop(jq);
jv* in = cfunc_input;
int i;
in[0] = top;
for (i = 1; i < nargs; i++) {
in[i] = stack_pop(jq);
}
struct cfunction* function = &frame_current(jq)->bc->globals->cfunctions[*pc++];
typedef jv (*func_1)(jv);
typedef jv (*func_2)(jv,jv);
typedef jv (*func_3)(jv,jv,jv);
typedef jv (*func_4)(jv,jv,jv,jv);
typedef jv (*func_5)(jv,jv,jv,jv,jv);
switch (function->nargs) {
case 1: top = ((func_1)function->fptr)(in[0]); break;
case 2: top = ((func_2)function->fptr)(in[0], in[1]); break;
case 3: top = ((func_3)function->fptr)(in[0], in[1], in[2]); break;
case 4: top = ((func_4)function->fptr)(in[0], in[1], in[2], in[3]); break;
case 5: top = ((func_5)function->fptr)(in[0], in[1], in[2], in[3], in[4]); break;
default: return jv_invalid_with_msg(jv_string("Function takes too many arguments"));
}
if (jv_is_valid(top)) {
stack_push(jq, top);
} else {
print_error(jq, top);
goto do_backtrack;
}
break;
}
case CALL_JQ: {
jv input = stack_pop(jq);
uint16_t nclosures = *pc++;
uint16_t* retaddr = pc + 2 + nclosures*2;
struct frame* new_frame = frame_push(jq, make_closure(jq, pc),
pc + 2, nclosures);
new_frame->retdata = jq->stk_top;
new_frame->retaddr = retaddr;
pc = new_frame->bc->code;
stack_push(jq, input);
break;
}
case RET: {
jv value = stack_pop(jq);
assert(jq->stk_top == frame_current(jq)->retdata);
uint16_t* retaddr = frame_current(jq)->retaddr;
if (retaddr) {
// function return
pc = retaddr;
frame_pop(jq);
} else {
// top-level return, yielding value
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, jv_null());
stack_save(jq, pc - 1, spos);
return value;
}
stack_push(jq, value);
break;
}
case ON_BACKTRACK(RET): {
// resumed after top-level return
goto do_backtrack;
}
}
}
}
jv jq_next(jq_state *jq) {
jv cfunc_input[MAX_CFUNCTION_ARGS];
uint16_t* pc = stack_restore(jq);
assert(pc);
int backtracking = !jq->initial_execution;
jq->initial_execution = 0;
while (1) {
uint16_t opcode = *pc;
if (jq->debug_trace_enabled) {
dump_operation(frame_current_bytecode(&jq->frame_stk), pc);
printf("\t");
const struct opcode_description* opdesc = opcode_describe(opcode);
data_stk_elem* param = 0;
int stack_in = opdesc->stack_in;
if (stack_in == -1) stack_in = pc[1];
for (int i=0; i<stack_in; i++) {
if (i == 0) {
param = forkable_stack_peek(&jq->data_stk);
} else {
printf(" | ");
param = forkable_stack_peek_next(&jq->data_stk, param);
}
if (!param) break;
jv_dump(jv_copy(param->val), 0);
//printf("<%d>", jv_get_refcnt(param->val));
//printf(" -- ");
//jv_dump(jv_copy(jq->path), 0);
}
if (backtracking) printf("\t<backtracking>");
printf("\n");
}
if (backtracking) {
opcode = ON_BACKTRACK(opcode);
backtracking = 0;
}
pc++;
switch (opcode) {
default: assert(0 && "invalid instruction");
case LOADK: {
jv v = jv_array_get(jv_copy(frame_current_bytecode(&jq->frame_stk)->constants), *pc++);
assert(jv_is_valid(v));
jv_free(stack_pop(jq));
stack_push(jq, v);
break;
}
case DUP: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
break;
}
case DUP2: {
jv keep = stack_pop(jq);
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, keep);
stack_push(jq, v);
break;
}
case SUBEXP_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
jq->subexp_nest++;
break;
}
case SUBEXP_END: {
assert(jq->subexp_nest > 0);
jq->subexp_nest--;
jv a = stack_pop(jq);
jv b = stack_pop(jq);
stack_push(jq, a);
stack_push(jq, b);
break;
}
case POP: {
jv_free(stack_pop(jq));
break;
}
case APPEND: {
jv v = stack_pop(jq);
uint16_t level = *pc++;
uint16_t vidx = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, vidx);
assert(jv_get_kind(*var) == JV_KIND_ARRAY);
*var = jv_array_append(*var, v);
break;
}
case INSERT: {
jv stktop = stack_pop(jq);
jv v = stack_pop(jq);
jv k = stack_pop(jq);
jv objv = stack_pop(jq);
assert(jv_get_kind(objv) == JV_KIND_OBJECT);
if (jv_get_kind(k) == JV_KIND_STRING) {
stack_push(jq, jv_object_set(objv, k, v));
stack_push(jq, stktop);
} else {
print_error(jv_invalid_with_msg(jv_string_fmt("Cannot use %s as object key",
jv_kind_name(jv_get_kind(k)))));
jv_free(stktop);
jv_free(v);
jv_free(k);
jv_free(objv);
goto do_backtrack;
}
break;
}
case ON_BACKTRACK(RANGE):
case RANGE: {
uint16_t level = *pc++;
uint16_t v = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, v);
jv max = stack_pop(jq);
if (jv_get_kind(*var) != JV_KIND_NUMBER ||
jv_get_kind(max) != JV_KIND_NUMBER) {
print_error(jv_invalid_with_msg(jv_string_fmt("Range bounds must be numeric")));
jv_free(max);
goto do_backtrack;
} else if (jv_number_value(jv_copy(*var)) >= jv_number_value(jv_copy(max))) {
/* finished iterating */
goto do_backtrack;
} else {
jv curr = jv_copy(*var);
*var = jv_number(jv_number_value(*var) + 1);
stack_save(jq, pc - 3);
stack_push(jq, jv_copy(max));
stack_switch(jq);
stack_push(jq, curr);
}
break;
}
// FIXME: loadv/storev may do too much copying/freeing
case LOADV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, v);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(*var), 0);
printf("\n");
}
jv_free(stack_pop(jq));
stack_push(jq, jv_copy(*var));
break;
}
case STOREV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, v);
jv val = stack_pop(jq);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(val), 0);
printf("\n");
}
jv_free(*var);
*var = val;
break;
}
case PATH_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jq->path);
stack_save(jq, pc - 1);
stack_switch(jq);
stack_push(jq, jv_number(jq->subexp_nest));
stack_push(jq, v);
jq->path = jv_array();
jq->subexp_nest = 0;
break;
}
case PATH_END: {
jv v = stack_pop(jq);
jv_free(v); // discard value, only keep path
int old_subexp_nest = (int)jv_number_value(stack_pop(jq));
jv path = jq->path;
jq->path = stack_pop(jq);
stack_save(jq, pc - 1);
stack_push(jq, jv_copy(path));
stack_switch(jq);
stack_push(jq, path);
jq->subexp_nest = old_subexp_nest;
break;
}
case ON_BACKTRACK(PATH_BEGIN):
case ON_BACKTRACK(PATH_END): {
jv_free(jq->path);
jq->path = stack_pop(jq);
goto do_backtrack;
}
case INDEX: {
jv t = stack_pop(jq);
jv k = stack_pop(jq);
path_append(jq, jv_copy(k));
jv v = jv_get(t, k);
if (jv_is_valid(v)) {
stack_push(jq, v);
} else {
print_error(v);
goto do_backtrack;
}
break;
}
case JUMP: {
uint16_t offset = *pc++;
pc += offset;
break;
}
case JUMP_F: {
uint16_t offset = *pc++;
jv t = stack_pop(jq);
jv_kind kind = jv_get_kind(t);
if (kind == JV_KIND_FALSE || kind == JV_KIND_NULL) {
pc += offset;
}
stack_push(jq, t); // FIXME do this better
break;
}
case EACH:
stack_push(jq, jv_number(-1));
// fallthrough
case ON_BACKTRACK(EACH): {
int idx = jv_number_value(stack_pop(jq));
jv container = stack_pop(jq);
int keep_going;
jv key, value;
if (jv_get_kind(container) == JV_KIND_ARRAY) {
if (opcode == EACH) idx = 0;
else idx = idx + 1;
keep_going = idx < jv_array_length(jv_copy(container));
if (keep_going) {
key = jv_number(idx);
value = jv_array_get(jv_copy(container), idx);
}
} else if (jv_get_kind(container) == JV_KIND_OBJECT) {
if (opcode == EACH) idx = jv_object_iter(container);
else idx = jv_object_iter_next(container, idx);
keep_going = jv_object_iter_valid(container, idx);
if (keep_going) {
key = jv_object_iter_key(container, idx);
value = jv_object_iter_value(container, idx);
}
} else {
assert(opcode == EACH);
print_error(jv_invalid_with_msg(jv_string_fmt("Cannot iterate over %s",
jv_kind_name(jv_get_kind(container)))));
keep_going = 0;
}
if (!keep_going) {
jv_free(container);
goto do_backtrack;
} else {
stack_save(jq, pc - 1);
stack_push(jq, container);
stack_push(jq, jv_number(idx));
stack_switch(jq);
path_append(jq, key);
stack_push(jq, value);
}
break;
}
do_backtrack:
case BACKTRACK: {
pc = stack_restore(jq);
if (!pc) {
return jv_invalid();
}
backtracking = 1;
break;
}
case FORK: {
stack_save(jq, pc - 1);
stack_switch(jq);
pc++; // skip offset this time
break;
}
case ON_BACKTRACK(FORK): {
uint16_t offset = *pc++;
pc += offset;
break;
}
case CALL_BUILTIN: {
int nargs = *pc++;
jv top = stack_pop(jq);
cfunc_input[0] = top;
for (int i = 1; i < nargs; i++) {
cfunc_input[i] = stack_pop(jq);
}
struct cfunction* func = &frame_current_bytecode(&jq->frame_stk)->globals->cfunctions[*pc++];
top = cfunction_invoke(func, cfunc_input);
if (jv_is_valid(top)) {
stack_push(jq, top);
} else {
print_error(top);
goto do_backtrack;
}
break;
}
case CALL_JQ: {
uint16_t nclosures = *pc++;
uint16_t* retaddr = pc + 2 + nclosures*2;
frame_ptr new_frame = frame_push(&jq->frame_stk,
make_closure(&jq->frame_stk, frame_current(&jq->frame_stk), pc),
retaddr);
pc += 2;
frame_ptr old_frame = forkable_stack_peek_next(&jq->frame_stk, new_frame);
assert(nclosures == frame_self(new_frame)->bc->nclosures);
for (int i=0; i<nclosures; i++) {
*frame_closure_arg(new_frame, i) = make_closure(&jq->frame_stk, old_frame, pc);
pc += 2;
}
pc = frame_current_bytecode(&jq->frame_stk)->code;
break;
}
case RET: {
uint16_t* retaddr = *frame_current_retaddr(&jq->frame_stk);
if (retaddr) {
// function return
pc = retaddr;
frame_pop(&jq->frame_stk);
} else {
// top-level return, yielding value
jv value = stack_pop(jq);
stack_save(jq, pc - 1);
stack_push(jq, jv_null());
stack_switch(jq);
return value;
}
break;
}
case ON_BACKTRACK(RET): {
// resumed after top-level return
goto do_backtrack;
}
}
}
}
