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#include "cmark-gfm.h"
#include "parser.h"
#include "footnotes.h"
#include "inlines.h"
#include "chunk.h"
static void footnote_free(cmark_map *map, cmark_map_entry *_ref) {
cmark_footnote *ref = (cmark_footnote *)_ref;
cmark_mem *mem = map->mem;
if (ref != NULL) {
mem->free(ref->entry.label);
if (ref->node)
cmark_node_free(ref->node);
mem->free(ref);
}
}
void cmark_footnote_create(cmark_map *map, cmark_node *node) {
cmark_footnote *ref;
unsigned char *reflabel = normalize_map_label(map->mem, &node->as.literal);
/* empty footnote name, or composed from only whitespace */
if (reflabel == NULL)
return;
assert(map->sorted == NULL);
ref = (cmark_footnote *)map->mem->calloc(1, sizeof(*ref));
ref->entry.label = reflabel;
ref->node = node;
ref->entry.age = map->size;
ref->entry.next = map->refs;
map->refs = (cmark_map_entry *)ref;
map->size++;
}
cmark_map *cmark_footnote_map_new(cmark_mem *mem) {
return cmark_map_new(mem, footnote_free);
}
// Before calling `cmark_map_free` on a map with `cmark_footnotes`, first
// unlink all of the footnote nodes before freeing their memory.
//
// Sometimes, two (unused) footnote nodes can end up referencing each other,
// which as they get freed up by calling `cmark_map_free` -> `footnote_free` ->
// etc, can lead to a use-after-free error.
//
// Better to `unlink` every footnote node first, setting their next, prev, and
// parent pointers to NULL, and only then walk thru & free them up.
void cmark_unlink_footnotes_map(cmark_map *map) {
cmark_map_entry *ref;
cmark_map_entry *next;
ref = map->refs;
while(ref) {
next = ref->next;
if (((cmark_footnote *)ref)->node) {
cmark_node_unlink(((cmark_footnote *)ref)->node);
}
ref = next;
}
}
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