Commit 42664023454783c7e7a216075244fa675248f315

Ran Benita 2015-11-21T23:12:18

doc/keymap-format-text-v1: convert to markdown Make it more readable for random browsing. Signed-off-by: Ran Benita <ran234@gmail.com>

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diff --git a/doc/keymap-format-text-v1.md b/doc/keymap-format-text-v1.md
new file mode 100644
index 0000000..27e561e
--- /dev/null
+++ b/doc/keymap-format-text-v1.md
@@ -0,0 +1,359 @@
+# The `xkb_keycodes` section
+
+This is the simplest section type, and is the first one to be
+compiled. The purpose of this is mostly to map between the
+hardware/evdev scancodes and xkb keycodes. Each key is given a name
+by which it can be referred to later, e.g. in the symbols section.
+
+## Keycode statements
+
+Statements of the form:
+
+    <TLDE> = 49;
+    <AE01> = 10;
+
+The above would let 49 and 10 be valid keycodes in the keymap, and
+assign them the names `TLDE` and `AE01` respectively. The format
+`<WXYZ>` is always used to refer to a key by name.
+
+[The naming convention `<AE01>` just denotes the position of the key
+in the main alphanumric section of a standard QWERTY keyboard, with
+the two letters specifying the row and the two digits specifying the
+column, from the bottom left.]
+
+In the common case this just maps to the evdev scancodes from
+`/usr/include/linux/input.h`, e.g. the following definitions:
+
+     #define KEY_GRAVE            41
+     #define KEY_1                2
+
+correspond to the ones above. Similar definitions appear in the
+xf86-input-keyboard driver. Note that in all current keymaps there's a
+constant offset of 8 (for historical reasons).
+
+If there's a conflict, like the same name given to different keycodes,
+or same keycode given different names, it is resolved according to the
+merge mode which applies to the definitions.
+
+## Alias statements
+
+Statements of the form:
+
+    alias <MENU> = <COMP>;
+
+Allows to refer to a previously defined key (here `<COMP>`) by another
+name (here `<MENU>`). Conflicts are handled similarly to keycode
+statements.
+
+## LED name statements
+
+Statements of the form:
+
+    indicator 1 = "Caps Lock";
+    indicator 2 = "Num Lock";
+    indicator 3 = "Scroll Lock";
+
+Assigns a name to the keyboard LED (AKA indicator) with the given
+index. The LED may be referred by this name later in the compat
+section and by the user.
+
+
+# The `xkb_types` section
+
+This section is the second to be processesed, after `xkb_keycodes`.
+However, it is completely independent and could have been the first to
+be processed (it does not refer to specific keys as specified in the
+`xkb_keycodes` section).
+
+This section defines key types, which, given a key and a keyboard
+state (i.e. modifier state and group), determine the shift level to be
+used in translating the key to keysyms. These types are assigned to
+each group in each key, in the `xkb_symbols` section.
+
+Key types are called this way because, in a way, they really describe
+the "type" of the key (or more correctly, a specific group of the
+key). For example, an ordinary keymap will provide a type called
+`KEYPAD`, which consists of two levels, with the second level being
+chosen according to the state of the Num Lock (or Shift) modifiers.
+Another example is a type called `ONE_LEVEL`, which is usually
+assigned to keys such as Escape; these have just one level and are not
+affected by the modifier state. Yet more common examples are
+`TWO_LEVEL` (with Shift choosing the second level), `ALPHABETIC`
+(where Caps Lock may also choose the second level), etc.
+
+## Type definitions
+
+Statements of the form:
+
+    type "FOUR_LEVEL" { ... }
+
+The above would create a new type named `FOUR_LEVEL`.
+The body of the definition may include statements of the following
+forms:
+
+### `level_name` statements
+
+    level_name[Level1] = "Base";
+
+Mandatory for each level in the type.
+
+Gives each level in this type a descriptive name. It isn't used
+for anything.
+
+Note: A level may be specified as Level[1-8] or just a number (can
+be more than 8).
+
+### `modifiers` statement
+
+    modifiers = Shift+Lock+LevelThree;
+
+Mandatory, should be specified only once.
+
+A mask of real and virtual modifiers. These are the only modifiers
+being considered when matching the modifier state against the type.
+The other modifiers, whether active or not, are masked out in the
+calculation.
+
+### `map` entry statements
+
+    map[Shift+LevelThree] = Level4;
+
+Should have at least as many mappings as there are levels in the type.
+
+If the active modifiers, masked with the type's modifiers (as stated
+above), match (i.e. equal) the modifiers inside the `map[]` statement,
+then the level in the right hand side is chosen. For example, in the
+above, if in the current keyboard state the `Shift` and `LevelThree`
+modifiers are active, while the `Lock` modifier is not, then the
+keysym(s) in the 4th level of the group will be returned to the user.
+
+### `preserve` statements
+
+    map[Shift+Lock+LevelThree] = Level5;
+    preserve[Shift+Lock+LevelThree] = Lock;
+
+When a key type is used for keysym translation, its modifiers are said
+to be "consumed". For example, in a simple US keymap, the "g" "g" key
+is assigned an ordinary `ALPHABETIC` key type, whose modifiers are
+Shift and Lock; then for the "g" key, these two modifiers are consumed
+by the translation. This information is relevant for applications
+which further process the modifiers, since by then the consumed
+modifiers have already "done their part" and should be masked out.
+
+However, sometimes even if a modifier had already affected the key
+translation through the type, it should *not* be reported as consumed,
+for various reasons. In this case, a `preserve[]` statement can be
+used to augment the map entry. The modifiers inside the square
+brackets should match one of the map[] statements in the type (if
+there is no matching map entry, one mapping to Level1 is implicitly
+added). The right hand side should consists of modifiers from the
+type's modifiers; these modifiers are then "preserved" and not
+reported as consumed.
+
+
+# The `xkb_compat` section
+
+This section is the third to be processed, after `xkb_keycodes` and
+`xkb_types`.
+
+## Interpret statements
+
+Statements of the form:
+
+    interpret Num_Lock+Any { ... }
+    interpret Shift_Lock+AnyOf(Shift+Lock) { ... }
+
+The `xkb_symbols` section (see below) allows the keymap author to
+perform, among other things, the following things for each key:
+
+- Bind an action, like SetMods or LockGroup, to the key. Actions, like
+  symbols, are specified for each level of each group in the key
+  separately.
+
+- Add a virtual modifier to the key's virtual modifier mapping
+  (vmodmap).
+
+- Specify whether the key should repeat or not.
+
+However, doing this for each key (or level) is tedious and inflexible.
+Interpret's are a mechanism to apply these settings to a bunch of
+keys/levels at once.
+
+Each interpret specifies a condition by which it attaches to certain
+levels. The condition consists of two parts:
+
+- A keysym. If the level has a different (or more than one) keysym,
+  the match fails. Leaving out the keysym is equivalent to using the
+  `NoSymbol` keysym, which always matches successfully.
+
+- A modifier predicate. The predicate consists of a matching operation
+  and a mask of (real) modifiers. The modifiers are matched against
+  the key's modifier map (modmap). The matching operation can be one
+  of the following:
+
+  * `AnyOfOrNone` - The modmap must either be empty or include at
+    least one of the specified modifiers.
+  * `AnyOf` - The modmap must include at least one of the specified
+    modifiers.
+  * `NoneOf` - The modmap must not include any of the specified
+    modifiers.
+  * `AllOf` - The modmap must include all of the specified modifiers
+    (but may include others as well).
+  * `Exactly` - The modmap must be exactly the same as the specified
+    modifiers.
+
+  Leaving out the predicate is equivalent to using `AnyOfOrNone` while
+  specifying all modifiers. Leaving out just the matching condition is
+  equivalent to using `Exactly`.
+
+An interpret may also include `useModMapMods = level1;` - see below.
+
+If a level fulfils the conditions of several interprets, only the
+most specific one is used:
+
+- A specific keysym will always match before a generic `NoSymbol`
+  condition.
+
+- If the keysyms are the same, the interpret with the more specific
+  matching operation is used. The above list is sorted from least to
+  most specific.
+
+- If both the keysyms and the matching operations are the same (but the
+  modifiers are different), the first interpret is used.
+
+As described above, once an interpret "attaches" to a level, it can bind
+an action to that level, add one virtual modifier to the key's vmodmap,
+or set the key's repeat setting. You should note the following:
+
+- The key repeat is a property of the entire key; it is not
+  level-specific. In order to avoid confusion, it is only inspected
+  for the first level of the first group; the interpret's repeat
+  setting is ignored when applied to other levels.
+
+- If one of the above fields was set directly for a key in
+  `xkb_symbols`, the explicit setting takes precedence over the
+  interpret.
+
+The body of the statement may include statements of the following
+forms (all of which are optional):
+
+### `useModMapMods` statement
+
+    useModMapMods = level1;
+
+When set to `level1`, the interpret will only match levels which are
+the first level of the first group of the keys. This can be useful in
+conjunction with e.g. a `virtualModifier` statement.
+
+### `action` statement
+
+    action = LockMods(modifiers=NumLock);
+
+Bind this action to the matching levels.
+
+### `virtualModifier` statement
+
+    virtualModifier = NumLock;
+
+Add this virtual modifier to the key's vmodmap. The given virtual
+modifier must be declared at the top level of the file with a
+`virtual_modifiers` statement, e.g.:
+
+    virtual_modifiers NumLock;
+
+### `repeat` statement
+
+    repeat = True;
+
+Set whether the key should repeat or not. Must be a boolean value.
+
+## LED map statements
+
+Statements of the form:
+
+    indicator "Shift Lock" { ... }
+
+This statement specifies the behavior and binding of the LED (AKA
+indicator) with the given name ("Shift Lock" above). The name should
+have been declared previously in the `xkb_keycodes` section (see LED
+name statement), and given an index there. If it wasn't, it is created
+with the next free index.
+
+The body of the statement describes the conditions of the keyboard
+state which will cause the LED to be lit. It may include the following
+statements:
+
+### `modifiers` statement
+
+    modifiers = ScrollLock;
+
+If the given modifiers are in the required state (see below), the
+LED is lit.
+
+### `whichModState` statment
+
+    whichModState = Latched+Locked;
+
+Can be any combination of:
+
+* `base`, `latched`, `locked`, `effective`
+* `any` (i.e. all of the above)
+* `none` (i.e. none of the above)
+* `compat` (legacy value, treated as effective)
+
+This will cause the respective portion of the modifier state (see
+`struct xkb_state`) to be matched against the modifiers given in the
+`modifiers` statement.
+
+Here's a simple example:
+
+indicator "Num Lock" {
+    modifiers = NumLock;
+    whichModState = Locked;
+};
+
+Whenever the NumLock modifier is locked, the Num Lock LED will light
+up.
+
+### `groups` statement
+
+    groups = All - group1;
+
+If the given groups are in the required state (see below), the LED is
+lit.
+
+### `whichGroupState` statement
+
+    whichGroupState = Effective;
+
+Can be any combination of:
+
+* `base`, `latched`, `locked`, `effective`
+* `any` (i.e. all of the above)
+* `none` (i.e. none of the above)
+
+This will cause the respective portion of the group state (see
+`struct xkb_state`) to be matched against the groups given in the
+`groups` statement.
+
+Note: the above conditions are disjunctive, i.e. if any of them are
+satisfied the LED is lit.
+
+
+# The `xkb_symbols` section
+
+This section is the fourth to be processed, after `xkb_keycodes`,
+`xkb_types` and `xkb_compat`.
+
+TODO
+
+
+# Virtual modifier statements
+
+Statements of the form:
+
+    virtual_modifiers LControl;
+
+Can appear in the `xkb_types`, `xkb_compat`, `xkb_symbols` sections.
+
+TODO
diff --git a/doc/keymap-format-text-v1.txt b/doc/keymap-format-text-v1.txt
deleted file mode 100644
index c32f44e..0000000
--- a/doc/keymap-format-text-v1.txt
+++ /dev/null
@@ -1,354 +0,0 @@
-The xkb_keycodes section
-========================
-
-This is the simplest section type, and is the first one to be
-compiled. The purpose of this is mostly to map between the
-hardware/evdev scancodes and xkb keycodes. Each key is given a name
-by which it can be referred to later, e.g. in the symbols section.
-
-Keycode statements
-------------------
-Statements of the form:
-
-    <TLDE> = 49;
-    <AE01> = 10;
-
-The above would let 49 and 10 be valid keycodes in the keymap, and
-assign them the names TLDE and AE01 respectively. The format <WXYZ> is
-always used to refer to a key by name.
-
-[The naming convention <AE01> just denoted the position of the key
-in the main alphanumric section of the keyboard, with the two letters
-specifying the row and the two digits specifying the column, from
-the bottom left.]
-
-In the common case this just maps to the evdev scancodes from
-/usr/include/linux/input.h, e.g. the following definitions:
-
-     #define KEY_GRAVE            41
-     #define KEY_1                2
-
-correspond to the ones above. Similar definitions appear in the
-xf86-input-keyboard driver. Note that in all current keymaps there's a
-constant offset of 8 (for historical reasons).
-
-If there's a conflict, like the same name given to different keycodes,
-or same keycode given different names, it is resolved according to the
-merge mode which applies to the definitions.
-
-Alias statements
-----------------
-Statements of the form:
-
-    alias <MENU> = <COMP>;
-
-Allows to refer to a previously defined key (here <COMP>) by another
-name (here <MENU>). Conflicts are handled similarly to keycode
-statements.
-
-LED name statements
--------------------
-Statements of the form:
-
-    indicator 1 = "Caps Lock";
-    indicator 2 = "Num Lock";
-    indicator 3 = "Scroll Lock";
-
-Assigns a name to the keyboard LED (a.k.a indicator) with the given
-index. The LED may be referred by this name later in the compat section
-and by the user.
-
-
-The xkb_types section
-=====================
-
-This section is the second to be processesed, after xkb_keycodes.
-However, it is completely independent and could have been the first
-to be processed (it does not refer to specific keys as specified in
-the xkb_keycodes section).
-
-This section defines key types, which, given a key and a keyboard
-state (i.e. modifier state and group), determine the shift level to
-be used in translating the key to keysyms. These types are assigned
-to each group in each key, in the xkb_symbols section.
-
-Key types are called this way because, in a way, they really describe
-the "type" of the key (or more correctly, a specific group of the
-key). For example, an ordinary keymap will provide a type called
-"KEYPAD", which consists of two levels, with the second level being
-chosen according to the state of the Num Lock (or Shift) modifiers.
-Another example is a type called "ONE_LEVEL", which is usually
-assigned to keys such as Escape; these have just one level and are
-not affected by the modifier state. Yet more common examples are
-"TWO_LEVEL" (with Shift choosing the second level), "ALPHABETIC"
-(where Caps Lock may also choose the second level), etc.
-
-Type definitions
-----------------
-Statements of the form:
-
-    type "FOUR_LEVEL" { ... }
-
-The above would create a new type named "FOUR_LEVEL".
-The body of the definition may include statements of the following
-forms:
-
-- level_name statements (mandatory for each level in the type):
-
-        level_name[Level1] = "Base";
-
-  Gives each level in this type a descriptive name. It isn't used
-  for anything.
-  Note: A level may be specified as Level[1-8] or just a number (can
-  be more than 8).
-
-- modifiers statement (mandatory, should be specified only once):
-
-        modifiers = Shift+Lock+LevelThree;
-
-  A mask of real and virtual modifiers. These are the only modifiers
-  being considered when matching the modifier state against the type.
-  The other modifiers, whether active or not, are masked out in the
-  calculation.
-
-- map entry statements (should have at least as many mappings as there
-  are levels in the type):
-
-        map[Shift+LevelThree] = Level4;
-
-  If the active modifiers, masked with the type's modifiers (as stated
-  above), match (i.e. equal) the modifiers inside the map[] statement,
-  then the level in the right hand side is chosen. For example, in the
-  above, if in the current keyboard state the Shift and LevelThree
-  modifiers are active, while the Lock modifier is not, then the
-  keysym(s) in the 4th level of the group will be returned to the
-  user.
-
-- preserve statements:
-
-        map[Shift+Lock+LevelThree] = Level5;
-        preserve[Shift+Lock+LevelThree] = Lock;
-
-  When a key type is used for keysym translation, its modifiers are
-  said to be "consumed". For example, in a simple US keymap, the "g"
-  "g" key is assigned an ordinary ALPHABETIC key type, whose modifiers
-  are Shift and Lock; then for the "g" key, these two modifiers are
-  consumed by the translation. This information is relevant for
-  applications which further process the modifiers, since by then the
-  consumed modifiers have already "done their part" and should be
-  masked out.
-
-  However, sometimes even if a modifier had already affected the key
-  translation through the type, it should *not* be reported as
-  consumed, for various reasons. In this case, a preserve[] statement
-  can be used to augment the map entry. The modifiers inside the
-  square brackets should match one of the map[] statements in the type
-  (if there is no matching map entry, one mapping to Level1 is
-  implicitly added). The right hand side should consists of modifiers
-  from the type's modifiers; these modifiers are then "preserved" and
-  not reported as consumed.
-
-
-The xkb_compat section
-======================
-
-This section is the third to be processed, after xkb_keycodes and
-xkb_types.
-
-Interpret statements
---------------------
-Statements of the form:
-
-    interpret Num_Lock+Any { ... }
-    interpret Shift_Lock+AnyOf(Shift+Lock) { ... }
-
-The xkb_symbols section (see below) allows the keymap author to perform,
-among other things, the following things for each key:
-
-- Bind an action, like SetMods or LockGroup, to the key. Actions, like
-  symbols, are specified for each level of each group in the key
-  separately.
-
-- Add a virtual modifier to the key's virtual modifier mapping (vmodmap).
-
-- Specify whether the key should repeat or not.
-
-However, doing this for each key (or level) is tedious and inflexible.
-Interpret's are a mechanism to apply these settings to a bunch of
-keys/levels at once.
-
-Each interpret specifies a condition by which it attaches to certain
-levels. The condition consists of two parts:
-
-- A keysym. If the level has a different (or more than one) keysym, the
-  match fails. Leaving out the keysym is equivalent to using the NoSymbol
-  keysym, which always matches successfully.
-
-- A modifier predicate. The predicate consists of a matching operation
-  and a mask of (real) modifiers. The modifiers are matched against the
-  key's modifier map (modmap). The matching operation can be one of the
-  following:
-
-  * AnyOfOrNone - The modmap must either be empty or include at least
-    one of the specified modifiers.
-  * AnyOf - The modmap must include at least one of the specified
-    modifiers.
-  * NoneOf - The modmap must not include any of the specified modifiers.
-  * AllOf - The modmap must include all of the specified modifiers (but
-    may include others as well).
-  * Exactly - The modmap must be exactly the same as the specified
-    modifiers.
-
-  Leaving out the predicate is equivalent to using AnyOfOrNone while
-  specifying all modifiers. Leaving out just the matching condition
-  is equivalent to using Exactly.
-
-An interpret may also include "useModMapMods = level1;" - see below.
-
-If a level fulfils the conditions of several interpret's, only the
-most specific one is used:
-
-- A specific keysym will always match before a generic NoSymbol
-  condition.
-
-- If the keysyms are the same, the interpret with the more specific
-  matching operation is used. The above list is sorted from least to
-  most specific.
-
-- If both the keysyms and the matching operations are the same (but the
-  modifiers are different), the first interpret is used.
-
-As described above, once an interpret "attaches" to a level, it can bind
-an action to that level, add one virtual modifier to the key's vmodmap,
-or set the key's repeat setting. You should note the following:
-
-- The key repeat is a property of the entire key; it is not level-specific.
-  In order to avoid confusion, it is only inspected for the first level of
-  the first group; the interpret's repeat setting is ignored when applied
-  to other levels.
-
-- If one of the above fields was set directly for a key in xkb_symbols,
-  the explicit setting takes precedence over the interpret.
-
-The body of the statement may include statements of the following
-forms (all of which are optional):
-
-- useModMapMods statement:
-
-        useModMapMods = level1;
-
-  When set to 'level1', the interpret will only match levels which are
-  the first level of the first group of the keys. This can be useful in
-  conjunction with e.g. a virtualModifier statement.
-
-- action statement:
-
-        action = LockMods(modifiers=NumLock);
-
-  Bind this action to the matching levels.
-
-- virtual modifier statement:
-
-        virtualModifier = NumLock;
-
-  Add this virtual modifier to the key's vmodmap. The given virtual
-  modifier must be declared at the top level of the file with a
-  virtual_modifiers statement, e.g.:
-
-        virtual_modifiers NumLock;
-
-- repeat statement:
-
-        repeat = True;
-
-  Set whether the key should repeat or not. Must be a boolean value.
-
-LED map statements
-------------------
-Statements of the form:
-
-    indicator "Shift Lock" { ... }
-
-This statement specifies the behavior and binding of the LED (a.k.a
-indicator) with the given name ("Shift Lock" above). The name should
-have been declared previously in the xkb_keycodes section (see LED
-name statement), and given an index there. If it wasn't, it is created
-with the next free index.
-The body of the statement describes the conditions of the keyboard
-state which will cause the LED to be lit. It may include the following
-statements:
-
-- modifiers statement:
-
-        modifiers = ScrollLock;
-
-  If the given modifiers are in the required state (see below), the
-  LED is lit.
-
-- whichModifierState statment:
-
-        whichModState = Latched+Locked;
-
-  Can be any combination of:
-
-  * base, latched, locked, effective
-  * any (i.e. all of the above)
-  * none (i.e. none of the above)
-  * compat (legacy value, treated as effective)
-
-  This will cause the respective portion of the modifer state (see
-  struct xkb_state) to be matched against the modifiers given in the
-  "modifiers" statement.
-
-  Here's a simple example:
-
-    indicator "Num Lock" {
-        modifiers = NumLock;
-        whichModState = Locked;
-    };
-
-  Whenever the NumLock modifier is locked, the Num Lock LED will light
-  up.
-
-- groups statment:
-
-        groups = All - group1;
-
-  If the given groups are in the required state (see below), the LED
-  is lit.
-
-- whichGroupState statment:
-
-        whichGroupState = Effective;
-
-  Can be any combination of:
-
-  * base, latched, locked, effective
-  * any (i.e. all of the above)
-  * none (i.e. none of the above)
-
-  This will cause the respective portion of the group state (see
-  struct xkb_state) to be matched against the groups given in the
-  "groups" statement.
-
-  Note: the above conditions are disjunctive, i.e. if any of them are
-  satisfied the LED is lit.
-
-
-The xkb_symbols section
-=======================
-
-This section is the fourth to be processed, after xkb_keycodes,
-xkb_types and xkb_compat.
-
-TODO
-
-
-Virtual modifier statements
-===========================
-
-Statements of the form:
-    virtual_modifiers LControl;
-
-Can appear in the xkb_types, xkb_compat, xkb_symbols sections.
-TODO