src/scripting/lua/hooks.c

   1 /* Lua scripting hooks */
   2
   3 #ifdef HAVE_CONFIG_H
   4 #include "config.h"
   5 #endif
   6
   7 #include "elinks.h"
   8
   9 #include "cache/cache.h"
  10 #include "main/event.h"
  11 #include "protocol/uri.h"
  12 #include "scripting/lua/core.h"
  13 #include "scripting/lua/hooks.h"
  14 #include "session/location.h"
  15 #include "session/session.h"
  16 #include "util/string.h"
  17
  18
  19 /* The events that will trigger the functions below and what they are expected
  20  * to do is explained in doc/events.txt */
  21
  22 static enum evhook_status
  23 script_hook_goto_url(va_list ap, void *data)
  24 {
  25         lua_State *L = lua_state;
  26         unsigned char **url = va_arg(ap, unsigned char **);
  27         struct session *ses = va_arg(ap, struct session *);
  28         int err;
  29
  30         if (*url == NULL) return EVENT_HOOK_STATUS_NEXT;
  31
  32         lua_getglobal(L, "goto_url_hook");
  33         if (lua_isnil(L, -1)) {
  34                 /* The function is not defined */
  35                 lua_pop(L, 1);
  36                 return EVENT_HOOK_STATUS_NEXT;
  37         }
  38
  39         lua_pushstring(L, *url);
  40
  41         if (!ses || !have_location(ses)) {
  42                 lua_pushnil(L);
  43         } else {
  44                 lua_pushstring(L, struri(cur_loc(ses)->vs.uri));
  45         }
  46
  47         if (prepare_lua(ses)) return EVENT_HOOK_STATUS_NEXT;
  48
  49         err = lua_pcall(L, 2, 1, 0);
  50         finish_lua();
  51         if (err) return EVENT_HOOK_STATUS_NEXT;
  52
  53         if (lua_isstring(L, -1)) {
  54                 unsigned char *new_url;
  55
  56                 new_url = stracpy((unsigned char *) lua_tostring(L, -1));
  57                 if (new_url) {
  58                         mem_free_set(url, new_url);
  59                 }
  60         } else if (lua_isnil(L, -1)) {
  61                 (*url)[0] = 0;
  62         } else {
  63                 alert_lua_error("goto_url_hook must return a string or nil");
  64         }
  65
  66         lua_pop(L, 1);
  67
  68         return EVENT_HOOK_STATUS_NEXT;
  69 }
  70
  71 static enum evhook_status
  72 script_hook_follow_url(va_list ap, void *data)
  73 {
  74         lua_State *L = lua_state;
  75         unsigned char **url = va_arg(ap, unsigned char **);
  76         struct session *ses = va_arg(ap, struct session *);
  77         int err;
  78
  79         if (*url == NULL) return EVENT_HOOK_STATUS_NEXT;
  80
  81         lua_getglobal(L, "follow_url_hook");
  82         if (lua_isnil(L, -1)) {
  83                 /* The function is not defined */
  84                 lua_pop(L, 1);
  85                 return EVENT_HOOK_STATUS_NEXT;
  86         }
  87
  88         lua_pushstring(L, *url);
  89
  90         if (prepare_lua(ses)) return EVENT_HOOK_STATUS_NEXT;
  91
  92         err = lua_pcall(L, 1, 1, 0);
  93         finish_lua();
  94         if (err) return EVENT_HOOK_STATUS_NEXT;
  95
  96         if (lua_isstring(L, -1)) {
  97                 unsigned char *new_url;
  98
  99                 new_url = stracpy((unsigned char *) lua_tostring(L, -1));
 100                 if (new_url) {
 101                         mem_free_set(url, new_url);
 102                 }
 103         } else if (lua_isnil(L, -1)) {
 104                 (*url)[0] = 0;
 105         } else {
 106                 alert_lua_error("follow_url_hook must return a string or nil");
 107         }
 108
 109         lua_pop(L, 1);
 110
 111         return EVENT_HOOK_STATUS_NEXT;
 112 }
 113
 114 static enum evhook_status
 115 script_hook_pre_format_html(va_list ap, void *data)
 116 {
 117         lua_State *L = lua_state;
 118         struct session *ses = va_arg(ap, struct session *);
 119         struct cache_entry *cached = va_arg(ap, struct cache_entry *);
 120         struct fragment *fragment = get_cache_fragment(cached);
 121         unsigned char *url = struri(cached->uri);
 122         int err;
 123
 124         if (!cached->length || !*fragment->data) return EVENT_HOOK_STATUS_NEXT;
 125
 126         lua_getglobal(L, "pre_format_html_hook");
 127         if (lua_isnil(L, -1)) {
 128                 /* The function is not defined */
 129                 lua_pop(L, 1);
 130                 return EVENT_HOOK_STATUS_NEXT;
 131         }
 132
 133         lua_pushstring(L, url);
 134         lua_pushlstring(L, fragment->data, fragment->length);
 135
 136         if (prepare_lua(ses)) return EVENT_HOOK_STATUS_NEXT;
 137
 138         err = lua_pcall(L, 2, 1, 0);
 139         finish_lua();
 140         if (err) return EVENT_HOOK_STATUS_NEXT;
 141
 142         if (lua_isstring(L, -1)) {
 143                 int len = lua_strlen(L, -1);
 144
 145                 add_fragment(cached, 0, (unsigned char *) lua_tostring(L, -1), len);
 146                 normalize_cache_entry(cached, len);
 147         } else if (!lua_isnil(L, -1)) {
 148                 alert_lua_error("pre_format_html_hook must return a string or nil");
 149         }
 150
 151         lua_pop(L, 1);
 152
 153         return EVENT_HOOK_STATUS_NEXT;
 154 }
 155
 156 /* The Lua function can return:
 157  *  - "PROXY:PORT" to use the specified proxy
 158  *  - ""           to not use any proxy
 159  *  - nil          to use the default proxies */
 160 static enum evhook_status
 161 script_hook_get_proxy(va_list ap, void *data)
 162 {
 163         lua_State *L = lua_state;
 164         unsigned char **new_proxy_url = va_arg(ap, unsigned char **);
 165         unsigned char *url = va_arg(ap, unsigned char *);
 166         int err;
 167
 168         if (!new_proxy_url || !url)
 169                 return EVENT_HOOK_STATUS_NEXT;
 170
 171         lua_getglobal(L, "proxy_for_hook");
 172         if (lua_isnil(L, -1)) {
 173                 /* The function is not defined */
 174                 lua_pop(L, 1);
 175                 return EVENT_HOOK_STATUS_NEXT;
 176         }
 177
 178         lua_pushstring(L, url);
 179         if (prepare_lua(NULL)) return EVENT_HOOK_STATUS_NEXT;
 180
 181         err = lua_pcall(L, 1, 1, 0);
 182         finish_lua();
 183         if (err) return EVENT_HOOK_STATUS_NEXT;
 184
 185         if (lua_isstring(L, -1)) {
 186                 mem_free_set(new_proxy_url,
 187                              stracpy((unsigned char *) lua_tostring(L, -1)));
 188         } else if (lua_isnil(L, -1)) {
 189                 mem_free_set(new_proxy_url, NULL);
 190         } else {
 191                 alert_lua_error("proxy_hook must return a string or nil");
 192         }
 193
 194         lua_pop(L, 1);
 195
 196         return EVENT_HOOK_STATUS_NEXT;
 197 }
 198
 199 static enum evhook_status
 200 script_hook_quit(va_list ap, void *data)
 201 {
 202         if (!prepare_lua(NULL)) {
 203                 lua_dostring(lua_state, "if quit_hook then quit_hook() end");
 204                 finish_lua();
 205         }
 206
 207         return EVENT_HOOK_STATUS_NEXT;
 208 }
 209
 210 struct event_hook_info lua_scripting_hooks[] = {
 211         { "goto-url", 0, script_hook_goto_url, NULL },
 212         { "follow-url", 0, script_hook_follow_url, NULL },
 213         { "pre-format-html", 0, script_hook_pre_format_html, NULL },
 214         { "get-proxy", 0, script_hook_get_proxy, NULL },
 215         { "quit", 0, script_hook_quit, NULL },
 216         { "dialog-lua-console", 0, dialog_lua_console, NULL },
 217         { "free-history", 0, free_lua_console_history, NULL },
 218         NULL_EVENT_HOOK_INFO,
 219 };