input: support bindings with modifier keys for X input

Add support for binding commands to modifier+key combinations like
"Shift+Left" or "Ctrl+Alt+x", and support reading such combinations
from the output window of X VOs.

The recognized modifier names are Shift, Ctrl, Alt and Meta. Any
combination of those and then a non-modifier key name, separated by
'+', is accepted as a key name in input.conf. For non-special keys
that produce characters shift is ignored as a modifier. For example
"A" is handled as a key without modifiers even if you use shift to
write the capital letter; 'a' vs 'A' already distinguishes the
combinations with a normal keymap, and having separate 'a', 'Shift+A'
and 'A' (written with caps lock for example) would bring more
confusion than benefit.

Currently reading the modifier+key combinations is only supported in
the output window of those VOs that use x11_common.c event
handling. It's not possible to input the key combinations in other VOs
or in a terminal window.

etc/input.conf

@@ -10,6 +10,10 @@
 ## If you wish to unbind a key, use key ignore.
 ## e.g. ENTER ignore
 ##
+## You can use modifier-key combinations like Shift+Left or Ctrl+Alt+x with
+## modifiers Shift, Ctrl, Alt and Meta, but note that currently reading
+## key combinations is only supported through the video windows of X-based
+## output drivers (not in output windows of other drivers or in a terminal).
 
 RIGHT seek +10
 LEFT seek -10

input/input.c

@@ -45,6 +45,7 @@
 #include "path.h"
 #include "talloc.h"
 #include "options.h"
+#include "bstr.h"
 
 #include "joystick.h"
 
@@ -361,6 +362,16 @@ static const mp_key_name_t key_names[] = {
   { 0, NULL }
 };
 
+struct mp_key_name modifier_names[] = {
+    { KEY_MODIFIER_SHIFT, "Shift" },
+    { KEY_MODIFIER_CTRL,  "Ctrl" },
+    { KEY_MODIFIER_ALT,   "Alt" },
+    { KEY_MODIFIER_META,  "Meta" },
+    { 0 }
+};
+
+#define KEY_MODIFIER_MASK (KEY_MODIFIER_SHIFT | KEY_MODIFIER_CTRL | KEY_MODIFIER_ALT | KEY_MODIFIER_META)
+
 // This is the default binding. The content of input.conf overrides these.
 // The first arg is a null terminated array of key codes.
 // The second is the command
@@ -620,8 +631,27 @@ static const m_option_t mp_input_opts[] = {
 
 static int default_cmd_func(int fd,char* buf, int l);
 
-static char *get_key_name(int key, char buffer[12]);
+static char *get_key_name(int key)
+{
+    char *ret = talloc_strdup(NULL, "");
+    for (int i = 0; modifier_names[i].name; i++) {
+        if (modifier_names[i].key & key) {
+            ret = talloc_asprintf_append_buffer(ret, "%s+",
+                                                modifier_names[i].name);
+            key -= modifier_names[i].key;
+        }
+    }
+    for (int i = 0; key_names[i].name != NULL; i++) {
+        if (key_names[i].key == key)
+            return talloc_asprintf_append_buffer(ret, "%s", key_names[i].name);
+    }
 
+    if (isascii(key))
+        return talloc_asprintf_append_buffer(ret, "%c", key);
+
+    // Print the hex key code
+    return talloc_asprintf_append_buffer(ret, "%#-8x", key);
+}
 
 int mp_input_add_cmd_fd(struct input_ctx *ictx, int fd, int select,
                         mp_cmd_func_t read_func, mp_close_func_t close_func)
@@ -1034,7 +1064,6 @@ static mp_cmd_t *get_cmd_from_keys(struct input_ctx *ictx, int n, int *keys)
 {
   char* cmd = NULL;
   mp_cmd_t* ret;
-  char key_buf[12];
 
   if (ictx->cmd_binds)
     cmd = find_bind_for_key(ictx->cmd_binds, n, keys);
@@ -1044,12 +1073,16 @@ static mp_cmd_t *get_cmd_from_keys(struct input_ctx *ictx, int n, int *keys)
     cmd = find_bind_for_key(def_cmd_binds,n,keys);
 
   if(cmd == NULL) {
-      mp_tmsg(MSGT_INPUT,MSGL_WARN,"No bind found for key '%s'.", get_key_name(keys[0],
+      char *key_buf = get_key_name(keys[0]);
-                                                                  key_buf));
+      mp_tmsg(MSGT_INPUT,MSGL_WARN,"No bind found for key '%s'.", key_buf);
+      talloc_free(key_buf);
     if(n > 1) {
       int s;
-      for(s=1; s < n; s++)
+      for(s=1; s < n; s++) {
-          mp_msg(MSGT_INPUT,MSGL_WARN,"-%s", get_key_name(keys[s], key_buf));
+          key_buf = get_key_name(keys[s]);
+          mp_msg(MSGT_INPUT,MSGL_WARN,"-%s", key_buf);
+          talloc_free(key_buf);
+      }
     }
     mp_msg(MSGT_INPUT,MSGL_WARN,"                         \n");
     return NULL;
@@ -1057,13 +1090,16 @@ static mp_cmd_t *get_cmd_from_keys(struct input_ctx *ictx, int n, int *keys)
   if (strcmp(cmd, "ignore") == 0) return NULL;
   ret =  mp_input_parse_cmd(cmd);
   if(!ret) {
-    mp_tmsg(MSGT_INPUT,MSGL_ERR,"Invalid command for bound key %s",
+    char *key_buf = get_key_name(ictx->key_down[0]);
-           get_key_name(ictx->key_down[0], key_buf));
+    mp_tmsg(MSGT_INPUT,MSGL_ERR,"Invalid command for bound key %s", key_buf);
+    talloc_free(key_buf);
     if (ictx->num_key_down > 1) {
       unsigned int s;
-      for(s=1; s < ictx->num_key_down; s++)
+      for(s=1; s < ictx->num_key_down; s++) {
-          mp_msg(MSGT_INPUT,MSGL_ERR,"-%s", get_key_name(ictx->key_down[s],
+          char *key_buf = get_key_name(ictx->key_down[s]);
-                                                         key_buf));
+          mp_msg(MSGT_INPUT,MSGL_ERR,"-%s", key_buf);
+          talloc_free(key_buf);
+      }
     }
     mp_msg(MSGT_INPUT,MSGL_ERR," : %s             \n",cmd);
   }
@@ -1076,6 +1112,14 @@ static mp_cmd_t* interpret_key(struct input_ctx *ictx, int code)
   unsigned int j;
   mp_cmd_t* ret;
 
+    /* On normal keyboards shift changes the character code of non-special
+     * keys, so don't count the modifier separately for those. In other words
+     * we want to have "a" and "A" instead of "a" and "Shift+A"; but a separate
+     * shift modifier is still kept for special keys like arrow keys.
+     */
+    if ((code & ~KEY_MODIFIER_MASK) < 256)
+        code &= ~KEY_MODIFIER_SHIFT;
+
   if(mp_input_key_cb) {
       if (code & MP_KEY_DOWN)
 	  return NULL;
@@ -1371,38 +1415,31 @@ mp_cmd_clone(mp_cmd_t* cmd) {
   return ret;
 }
 
-static char *get_key_name(int key, char buffer[12])
+int mp_input_get_key_from_name(const char *name)
 {
-  int i;
+    int modifiers = 0;
-
+    const char *p;
-  for(i = 0; key_names[i].name != NULL; i++) {
+    while (p = strchr(name, '+')) {
-    if(key_names[i].key == key)
+        for (struct mp_key_name *m = modifier_names; m->name; m++)
-      return key_names[i].name;
+            if (!bstrcasecmp(BSTR(m->name), (struct bstr){name, p - name})) {
+                modifiers |= m->key;
+                goto found;
             }
-
+        if (!strcmp(name, "+"))
-  if(isascii(key)) {
+            return '+' + modifiers;
-    snprintf(buffer, 12, "%c",(char)key);
+        return -1;
-    return buffer;
+    found:
+        name = p + 1;
     }
+    int len = strlen(name);
+    if (len == 1)   // Direct key code
+        return (unsigned char)name[0] + modifiers;
+    else if (len > 2 && strncasecmp("0x", name, 2) == 0)
+        return strtol(name, NULL, 16) + modifiers;
 
-  // Print the hex key code
+    for (int i = 0; key_names[i].name != NULL; i++) {
-  snprintf(buffer, 12, "%#-8x",key);
+        if (strcasecmp(key_names[i].name, name) == 0)
-  return buffer;
+            return key_names[i].key + modifiers;
-
-}
-
-int
-mp_input_get_key_from_name(const char *name) {
-  int i,ret = 0,len = strlen(name);
-  if(len == 1) { // Direct key code
-    ret = (unsigned char)name[0];
-    return ret;
-  } else if(len > 2 && strncasecmp("0x",name,2) == 0)
-    return strtol(name,NULL,16);
-
-  for(i = 0; key_names[i].name != NULL; i++) {
-    if(strcasecmp(key_names[i].name,name) == 0)
-      return key_names[i].key;
     }
 
     return -1;
@@ -1595,10 +1632,14 @@ static int parse_config(struct input_ctx *ictx, char *file)
       // Found new line
       if(iter[0] == '\n' || iter[0] == '\r') {
 	int i;
-        char key_buf[12];
+        char *key_buf  = get_key_name(keys[0]);
-	mp_tmsg(MSGT_INPUT,MSGL_ERR,"No command found for key %s", get_key_name(keys[0], key_buf));
+	mp_tmsg(MSGT_INPUT,MSGL_ERR,"No command found for key %s", key_buf);
-	for(i = 1; keys[i] != 0 ; i++)
+        talloc_free(key_buf);
-            mp_msg(MSGT_INPUT,MSGL_ERR,"-%s", get_key_name(keys[i], key_buf));
+	for(i = 1; keys[i] != 0 ; i++) {
+            char *key_buf  = get_key_name(keys[i]);
+            mp_msg(MSGT_INPUT,MSGL_ERR,"-%s", key_buf);
+            talloc_free(key_buf);
+        }
         mp_msg(MSGT_INPUT,MSGL_ERR,"\n");
 	keys[0] = 0;
 	if(iter > buffer) {

libvo/x11_common.c

@@ -540,12 +540,12 @@ static const struct mp_keymap keysym_map[] = {
     {0, 0}
 };
 
-static void vo_x11_putkey_ext(struct vo *vo, int keysym)
+static void vo_x11_putkey_ext(struct vo *vo, int keysym, int modifiers)
 {
     struct mp_fifo *f = vo->key_fifo;
     int mpkey = lookup_keymap_table(keysym_map, keysym);
     if (mpkey)
-        mplayer_put_key(f, mpkey);
+        mplayer_put_key(f, mpkey + modifiers);
 }
 #endif
 
@@ -584,7 +584,7 @@ static const struct mp_keymap keymap[] = {
     {0, 0}
 };
 
-void vo_x11_putkey(struct vo *vo, int key)
+static void vo_x11_putkey(struct vo *vo, int key, int modifiers)
 {
     static const char *passthrough_keys = " -+*/<>`~!@#$%^&()_{}:;\"\',.?\\|=[]";
     int mpkey = 0;
@@ -598,7 +598,7 @@ void vo_x11_putkey(struct vo *vo, int key)
         mpkey = lookup_keymap_table(keymap, key);
 
     if (mpkey)
-        mplayer_put_key(vo->key_fifo, mpkey);
+        mplayer_put_key(vo->key_fifo, mpkey + modifiers);
 }
 
 
@@ -814,13 +814,22 @@ int vo_x11_check_events(struct vo *vo)
 
                     XLookupString(&Event.xkey, buf, sizeof(buf), &keySym,
                                   &x11->compose_status);
+                    int modifiers = 0;
+                    if (Event.xkey.state & ShiftMask)
+                        modifiers |= KEY_MODIFIER_SHIFT;
+                    if (Event.xkey.state & ControlMask)
+                        modifiers |= KEY_MODIFIER_CTRL;
+                    if (Event.xkey.state & Mod1Mask)
+                        modifiers |= KEY_MODIFIER_ALT;
+                    if (Event.xkey.state & Mod4Mask)
+                        modifiers |= KEY_MODIFIER_META;
 #ifdef XF86XK_AudioPause
-                    vo_x11_putkey_ext(vo, keySym);
+                    vo_x11_putkey_ext(vo, keySym, modifiers);
 #endif
                     key =
                         ((keySym & 0xff00) !=
                          0 ? ((keySym & 0x00ff) + 256) : (keySym));
-                    vo_x11_putkey(vo, key);
+                    vo_x11_putkey(vo, key, modifiers);
                     ret |= VO_EVENT_KEYPRESS;
                 }
                 break;

libvo/x11_common.h

@@ -170,8 +170,6 @@ void xv_setup_colorkeyhandling(struct vo *vo, const char *ck_method_str, const c
 int xv_test_ck( void * arg );
 int xv_test_ckm( void * arg );
 
-void vo_x11_putkey(struct vo *vo, int key);
-
 #ifdef CONFIG_XF86VM
 void vo_vm_switch(struct vo *vo);
 void vo_vm_close(struct vo *vo);

osdep/keycodes.h

@@ -94,4 +94,10 @@
 #define KEY_INTERN (0x1000)
 #define KEY_CLOSE_WIN (KEY_INTERN+0)
 
+/* Modifiers added to individual keys */
+#define KEY_MODIFIER_SHIFT  0x2000
+#define KEY_MODIFIER_CTRL   0x4000
+#define KEY_MODIFIER_ALT    0x8000
+#define KEY_MODIFIER_META  0x10000
+
 #endif /* MPLAYER_KEYCODES_H */