block gen_definedor(block a, block b) {
// var found := false
block found_var = gen_op_var_fresh(STOREV, "found");
block init = BLOCK(gen_op_simple(DUP), gen_const(jv_false()), found_var);
// if found, backtrack. Otherwise execute b
block backtrack = gen_op_simple(BACKTRACK);
block tail = BLOCK(gen_op_simple(DUP),
gen_op_bound(LOADV, found_var),
gen_op_target(JUMP_F, backtrack),
backtrack,
gen_op_simple(POP),
b);
// try again
block if_notfound = gen_op_simple(BACKTRACK);
// found := true, produce result
block if_found = BLOCK(gen_op_simple(DUP),
gen_const(jv_true()),
gen_op_bound(STOREV, found_var),
gen_op_target(JUMP, tail));
return BLOCK(init,
gen_op_target(FORK, if_notfound),
a,
gen_op_target(JUMP_F, if_found),
if_found,
if_notfound,
tail);
}
block gen_or(block a, block b) {
// a or b = if a then true else (if b then true else false)
return BLOCK(gen_op_simple(DUP), a,
gen_condbranch(BLOCK(gen_op_simple(POP), gen_const(jv_true())),
BLOCK(gen_op_simple(POP),
b,
gen_condbranch(gen_const(jv_true()),
gen_const(jv_false())))));
}
struct bytecode* jq_compile_args(const char* str, jv args) {
assert(jv_get_kind(args) == JV_KIND_ARRAY);
struct locfile locations;
locfile_init(&locations, str, strlen(str));
block program;
struct bytecode* bc = 0;
int nerrors = jq_parse(&locations, &program);
if (nerrors == 0) {
for (int i=0; i<jv_array_length(jv_copy(args)); i++) {
jv arg = jv_array_get(jv_copy(args), i);
jv name = jv_object_get(jv_copy(arg), jv_string("name"));
jv value = jv_object_get(arg, jv_string("value"));
program = gen_var_binding(gen_const(value), jv_string_value(name), program);
jv_free(name);
}
jv_free(args);
program = builtins_bind(program);
nerrors = block_compile(program, &locations, &bc);
}
if (nerrors) {
fprintf(stderr, "%d compile %s\n", nerrors, nerrors > 1 ? "errors" : "error");
}
locfile_free(&locations);
return bc;
}
block gen_collect(block expr) {
block array_var = gen_op_var_fresh(STOREV, "collect");
block c = BLOCK(gen_op_simple(DUP), gen_const(jv_array()), array_var);
block tail = BLOCK(gen_op_bound(APPEND, array_var),
gen_op_simple(BACKTRACK));
return BLOCK(c,
gen_op_target(FORK, tail),
expr,
tail,
gen_op_bound(LOADVN, array_var));
}
int jq_compile_args(jq_state *jq, const char* str, jv args) {
jv_nomem_handler(jq->nomem_handler, jq->nomem_handler_data);
assert(jv_get_kind(args) == JV_KIND_ARRAY);
struct locfile locations;
locfile_init(&locations, jq, str, strlen(str));
block program;
jq_reset(jq);
if (jq->bc) {
bytecode_free(jq->bc);
jq->bc = 0;
}
int nerrors = jq_parse(&locations, &program);
if (nerrors == 0) {
int i;
for (i=0; i<jv_array_length(jv_copy(args)); i++) {
jv arg = jv_array_get(jv_copy(args), i);
jv name = jv_object_get(jv_copy(arg), jv_string("name"));
jv value = jv_object_get(arg, jv_string("value"));
program = gen_var_binding(gen_const(value), jv_string_value(name), program);
jv_free(name);
}
nerrors = builtins_bind(jq, &program);
if (nerrors == 0) {
nerrors = block_compile(program, &locations, &jq->bc);
}
}
jv_free(args);
if (nerrors) {
jv s = jv_string_fmt("%d compile %s", nerrors,
nerrors > 1 ? "errors" : "error");
if (jq->err_cb != NULL)
jq->err_cb(jq->err_cb_data, s);
else if (!jv_is_valid(s))
fprintf(stderr, "Error formatting jq compilation errors: %s\n", strerror(errno));
else
fprintf(stderr, "%s\n", jv_string_value(s));
jv_free(s);
}
locfile_free(&locations);
return jq->bc != NULL;
}
