tomo/stdlib/pointers.c

85 lines
2.8 KiB
C

// Type infos and methods for Pointer types
#include <ctype.h>
#include <err.h>
#include <gc.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <sys/param.h>
#include "integers.h"
#include "metamethods.h"
#include "tables.h"
#include "text.h"
#include "types.h"
#include "util.h"
public Text_t Pointer$as_text(const void *x, bool colorize, const TypeInfo_t *type) {
auto ptr_info = type->PointerInfo;
if (!x) {
Text_t typename = generic_as_text(NULL, false, ptr_info.pointed);
Text_t text;
if (colorize)
text = Text$concat(Text("\x1b[34;1m"), Text$from_str(ptr_info.sigil), typename, Text("\x1b[m"));
else
text = Text$concat(Text$from_str(ptr_info.sigil), typename);
return text;
}
const void *ptr = *(const void**)x;
if (!ptr) {
Text_t typename = generic_as_text(NULL, false, ptr_info.pointed);
if (colorize)
return Text$concat(Text("\x1b[34;1m!"), typename, Text("\x1b[m"));
else
return Text$concat(Text("!"), typename);
}
static const void *root = NULL;
static Table_t pending = {};
bool top_level = (root == NULL);
// Check for recursive references, so if `x.foo = x`, then it prints as
// `@Foo{foo=@~1}` instead of overflowing the stack:
if (top_level) {
root = ptr;
} else if (ptr == root) {
return Text$format(colorize ? "\x1b[34;1m%s~1\x1b[m" : "%s~1", ptr_info.sigil);
} else {
TypeInfo_t rec_table = ((TypeInfo_t){.size=sizeof(Table_t), .align=__alignof__(Table_t), \
.tag=TableInfo, .TableInfo.key=type, .TableInfo.value=&Int64$info});
int64_t *id = Table$get(pending, x, &rec_table);
if (id)
return Text$format(colorize ? "\x1b[34;1m%s~%ld\x1b[m" : "%s~%ld", ptr_info.sigil, *id);
int64_t next_id = pending.entries.length + 2;
Table$set(&pending, x, &next_id, &rec_table);
}
Text_t pointed = generic_as_text(ptr, colorize, ptr_info.pointed);
if (top_level) {
pending = (Table_t){}; // Restore
root = NULL;
}
Text_t text;
if (colorize)
text = Text$concat(Text("\x1b[34;1m"), Text$from_str(ptr_info.sigil), Text("\x1b[m"), pointed);
else
text = Text$concat(Text$from_str(ptr_info.sigil), pointed);
return text;
}
PUREFUNC public int32_t Pointer$compare(const void *x, const void *y, const TypeInfo_t *type) {
(void)type;
const void *xp = *(const void**)x, *yp = *(const void**)y;
return (xp > yp) - (xp < yp);
}
PUREFUNC public bool Pointer$equal(const void *x, const void *y, const TypeInfo_t *type) {
(void)type;
const void *xp = *(const void**)x, *yp = *(const void**)y;
return xp == yp;
}
// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0