1 /*
2 * hyperlink.c
3 * Copyright (C) 2020 Kovid Goyal <kovid at kovidgoyal.net>
4 *
5 * Distributed under terms of the GPL3 license.
6 */
7
8 #include "hyperlink.h"
9 #include "kitty-uthash.h"
10 #include <string.h>
11
12 #define MAX_KEY_LEN 2048
13 #define MAX_ID_LEN 256
14 #define MAX_ADDS_BEFORE_GC 256
15
16 typedef struct {
17 const char *key;
18 hyperlink_id_type id;
19 UT_hash_handle hh;
20 } HyperLinkEntry;
21
22
23 typedef struct {
24 HyperLinkEntry *hyperlinks;
25 unsigned int max_link_id, num_of_adds_since_garbage_collection;
26 } HyperLinkPool;
27
28
29 static void
free_hyperlink_entry(HyperLinkEntry * s)30 free_hyperlink_entry(HyperLinkEntry *s) {
31 free((void*)s->key);
32 free(s);
33 }
34
35 static void
clear_pool(HyperLinkPool * pool)36 clear_pool(HyperLinkPool *pool) {
37 if (pool->hyperlinks) {
38 HyperLinkEntry *tmp, *s;
39 HASH_ITER(hh, pool->hyperlinks, s, tmp) {
40 HASH_DEL(pool->hyperlinks, s);
41 free_hyperlink_entry(s); s = NULL;
42 }
43 pool->max_link_id = 0;
44 }
45 }
46
47 HYPERLINK_POOL_HANDLE
alloc_hyperlink_pool(void)48 alloc_hyperlink_pool(void) {
49 return calloc(1, sizeof(HyperLinkPool));
50 }
51
52
53 void
clear_hyperlink_pool(HYPERLINK_POOL_HANDLE h)54 clear_hyperlink_pool(HYPERLINK_POOL_HANDLE h) {
55 if (h) {
56 HyperLinkPool *pool = (HyperLinkPool*)h;
57 clear_pool(pool);
58 }
59 }
60
61
62 void
free_hyperlink_pool(HYPERLINK_POOL_HANDLE h)63 free_hyperlink_pool(HYPERLINK_POOL_HANDLE h) {
64 if (h) {
65 HyperLinkPool *pool = (HyperLinkPool*)h;
66 clear_pool(pool);
67 free(pool);
68 }
69 }
70
71
72 void
screen_garbage_collect_hyperlink_pool(Screen * screen)73 screen_garbage_collect_hyperlink_pool(Screen *screen) {
74 HyperLinkPool *pool = (HyperLinkPool*)screen->hyperlink_pool;
75 pool->num_of_adds_since_garbage_collection = 0;
76 if (!pool->max_link_id) return;
77 hyperlink_id_type *map = calloc(HYPERLINK_MAX_NUMBER + 4, sizeof(hyperlink_id_type));
78 if (!map) fatal("Out of memory");
79 hyperlink_id_type num = remap_hyperlink_ids(screen, map);
80 if (num) {
81 HyperLinkEntry *s, *tmp;
82 pool->max_link_id = 0;
83 HASH_ITER(hh, pool->hyperlinks, s, tmp) {
84 if (map[s->id]) {
85 s->id = map[s->id];
86 pool->max_link_id = MAX(pool->max_link_id, s->id);
87 } else {
88 HASH_DEL(pool->hyperlinks, s);
89 free_hyperlink_entry(s); s = NULL;
90 }
91 }
92 } else clear_pool(pool);
93 free(map);
94 }
95
96
97 hyperlink_id_type
get_id_for_hyperlink(Screen * screen,const char * id,const char * url)98 get_id_for_hyperlink(Screen *screen, const char *id, const char *url) {
99 if (!url) return 0;
100 HyperLinkPool *pool = (HyperLinkPool*)screen->hyperlink_pool;
101 static char key[MAX_KEY_LEN] = {0};
102 int keylen = snprintf(key, MAX_KEY_LEN-1, "%.*s:%s", MAX_ID_LEN, id ? id : "", url);
103 if (keylen < 0) keylen = strlen(key);
104 else keylen = MIN(keylen, MAX_KEY_LEN - 2); // snprintf returns how many chars it would have written in case of truncation
105 key[keylen] = 0;
106 HyperLinkEntry *s = NULL;
107 if (pool->hyperlinks) {
108 HASH_FIND_STR(pool->hyperlinks, key, s);
109 if (s) {
110 // Remove and re-add s so that it is the last entry in the hash table and
111 // The first entry is discarded when hash table is full.
112 HASH_DEL(pool->hyperlinks, s);
113 HASH_ADD_KEYPTR(hh, pool->hyperlinks, s->key, strlen(s->key), s);
114 return s->id;
115 }
116 }
117 hyperlink_id_type new_id = 0;
118 if (pool->num_of_adds_since_garbage_collection >= MAX_ADDS_BEFORE_GC) screen_garbage_collect_hyperlink_pool(screen);
119 if (pool->max_link_id >= HYPERLINK_MAX_NUMBER && pool->hyperlinks) {
120 log_error("Too many hyperlinks, discarding oldest, this means some hyperlinks might be incorrect");
121 new_id = pool->hyperlinks->id;
122 HyperLinkEntry *s = pool->hyperlinks;
123 HASH_DEL(pool->hyperlinks, s);
124 free_hyperlink_entry(s); s = NULL;
125 }
126 s = malloc(sizeof(HyperLinkEntry));
127 if (!s) fatal("Out of memory");
128 s->key = malloc(keylen + 1);
129 if (!s->key) fatal("Out of memory");
130 memcpy((void*)s->key, key, keylen + 1);
131 s->id = new_id ? new_id : ++pool->max_link_id;
132 HASH_ADD_KEYPTR(hh, pool->hyperlinks, s->key, keylen, s);
133 pool->num_of_adds_since_garbage_collection++;
134 return s->id;
135 }
136
137 const char*
get_hyperlink_for_id(const HYPERLINK_POOL_HANDLE handle,hyperlink_id_type id,bool only_url)138 get_hyperlink_for_id(const HYPERLINK_POOL_HANDLE handle, hyperlink_id_type id, bool only_url) {
139 const HyperLinkPool *pool = (HyperLinkPool*)handle;
140 HyperLinkEntry *s, *tmp;
141 HASH_ITER(hh, pool->hyperlinks, s, tmp) {
142 if (s->id == id) return only_url ? strstr(s->key, ":") + 1 : s->key;
143 }
144 return NULL;
145 }
146
147
148 PyObject*
screen_hyperlinks_as_list(Screen * screen)149 screen_hyperlinks_as_list(Screen *screen) {
150 HyperLinkPool *pool = (HyperLinkPool*)screen->hyperlink_pool;
151 PyObject *ans = PyList_New(0);
152 HyperLinkEntry *s, *tmp;
153 HASH_ITER(hh, pool->hyperlinks, s, tmp) {
154 PyObject *e = Py_BuildValue("sH", s->key, s->id);
155 PyList_Append(ans, e);
156 Py_DECREF(e);
157 }
158 return ans;
159 }
160