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#include "cmark.h"
#include "utf8.h"
#include "references.h"
#include "inlines.h"
#include "chunk.h"
static unsigned int
refhash(const unsigned char *link_ref)
{
unsigned int hash = 0;
while (*link_ref)
hash = (*link_ref++) + (hash << 6) + (hash << 16) - hash;
return hash;
}
static void reference_free(reference *ref)
{
if(ref != NULL) {
free(ref->label);
free(ref->url);
free(ref->title);
free(ref);
}
}
// normalize reference: collapse internal whitespace to single space,
// remove leading/trailing whitespace, case fold
// Return NULL if the reference name is actually empty (i.e. composed
// solely from whitespace)
static unsigned char *normalize_reference(chunk *ref)
{
strbuf normalized = GH_BUF_INIT;
unsigned char *result;
if(ref == NULL)
return NULL;
if (ref->len == 0)
return NULL;
utf8proc_case_fold(&normalized, ref->data, ref->len);
strbuf_trim(&normalized);
strbuf_normalize_whitespace(&normalized);
result = strbuf_detach(&normalized);
assert(result);
if (result[0] == '\0') {
free(result);
return NULL;
}
return result;
}
static void add_reference(reference_map *map, reference* ref)
{
reference *t = ref->next = map->table[ref->hash % REFMAP_SIZE];
while (t) {
if (t->hash == ref->hash &&
!strcmp((char *)t->label, (char *)ref->label)) {
reference_free(ref);
return;
}
t = t->next;
}
map->table[ref->hash % REFMAP_SIZE] = ref;
}
extern void reference_create(reference_map *map, chunk *label, chunk *url, chunk *title)
{
reference *ref;
unsigned char *reflabel = normalize_reference(label);
/* empty reference name, or composed from only whitespace */
if (reflabel == NULL)
return;
ref = calloc(1, sizeof(*ref));
if(ref != NULL) {
ref->label = reflabel;
ref->hash = refhash(ref->label);
ref->url = clean_url(url);
ref->title = clean_title(title);
ref->next = NULL;
add_reference(map, ref);
}
}
// Returns reference if refmap contains a reference with matching
// label, otherwise NULL.
reference* reference_lookup(reference_map *map, chunk *label)
{
reference *ref = NULL;
unsigned char *norm;
unsigned int hash;
if (label->len > MAX_LINK_LABEL_LENGTH)
return NULL;
if (map == NULL)
return NULL;
norm = normalize_reference(label);
if (norm == NULL)
return NULL;
hash = refhash(norm);
ref = map->table[hash % REFMAP_SIZE];
while (ref) {
if (ref->hash == hash &&
!strcmp((char *)ref->label, (char *)norm))
break;
ref = ref->next;
}
free(norm);
return ref;
}
void reference_map_free(reference_map *map)
{
unsigned int i;
if(map == NULL)
return;
for (i = 0; i < REFMAP_SIZE; ++i) {
reference *ref = map->table[i];
reference *next;
while (ref) {
next = ref->next;
reference_free(ref);
ref = next;
}
}
free(map);
}
reference_map *reference_map_new(void)
{
return calloc(1, sizeof(reference_map));
}
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