Initial revision

src/alsa.h

@@ -0,0 +1,210 @@
+// SPDX-FileCopyrightText: 2022 Geoffrey D. Bennett <g@b4.vu>
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <alsa/asoundlib.h>
+#include <gtk/gtk.h>
+
+#include "const.h"
+
+// simulated cards have card->num set to -1
+#define SIMULATED_CARD_NUM -1
+
+// forward definitions
+struct alsa_elem;
+struct alsa_card;
+
+// typedef for callbacks to update widgets when the alsa element
+// notifies of a change
+typedef void (AlsaElemCallback)(struct alsa_elem *);
+
+// port categories for routing_src and routing_dst entries
+// must match the level meter ordering from the driver
+enum {
+  // Hardware inputs/outputs
+  PC_HW    = 0,
+
+  // Mixer inputs/outputs
+  PC_MIX   = 1,
+
+  // PCM inputs/outputs
+  PC_PCM   = 2,
+
+  // number of port categories
+  PC_COUNT = 3
+};
+
+// names for the port categories
+extern const char *port_category_names[PC_COUNT];
+
+// is a drag active, and whether dragging from a routing source or a
+// routing destination
+enum {
+  DRAG_TYPE_NONE = 0,
+  DRAG_TYPE_SRC  = 1,
+  DRAG_TYPE_DST  = 2,
+};
+
+// entry in alsa_card routing_srcs (routing sources) array
+// list of enums that are in the Mixer Input X Capture Enum elements
+struct routing_src {
+
+  // pointer back to the card this entry is associated with
+  struct alsa_card *card;
+
+  // the enum id of the alsa item
+  int id;
+
+  // PC_MIX, PC_PCM, or PC_HW
+  int port_category;
+
+  // 0-based count within port_category
+  int port_num;
+
+  // the alsa item name
+  char *name;
+
+  // the number (or translated letter; A = 1) in the item name
+  int lr_num;
+
+  // on the routing page, the box widget containing the text and the
+  // "socket" widget for this routing source
+  GtkWidget *widget;
+
+  // the socket widget
+  GtkWidget *widget2;
+};
+
+// entry in alsa_card routing_dsts (routing destinations) array
+// for alsa elements that are routing destinations like Analogue
+// Output 01 Playback Enum
+// port_category is set to PC_MIX, PC_PCM, PC_HW
+// port_num is a count (0-based) within that category
+struct routing_dst {
+
+  // location within the array
+  int idx;
+
+  // pointer back to the element this entry is associated with
+  struct alsa_elem *elem;
+
+  // PC_MIX, PC_PCM, or PC_HW
+  int port_category;
+
+  // 0-based count within port_category
+  int port_num;
+
+  // the mixer label widget for this destination
+  GtkWidget *mixer_label;
+};
+
+// entry in alsa_card elems (ALSA control elements) array
+struct alsa_elem {
+
+  // pointer back to the card
+  struct alsa_card *card;
+
+  // ALSA element information
+  int         numid;
+  const char *name;
+  int         type;
+  int         count;
+
+  // for the number (or translated letter; A = 1) in the item name
+  // TODO: move this to struct routing_dst?
+  int lr_num;
+
+  // the primary GTK widget and callback function for this ALSA
+  // control element
+  GtkWidget        *widget;
+  AlsaElemCallback *widget_callback;
+
+  // text label for volume controls
+  // handle for routing controls
+  // second button for dual controls
+  GtkWidget *widget2;
+
+  // for boolean buttons, the two possible texts
+  // for dual buttons, the four possible texts
+  const char *bool_text[4];
+
+  // for simulated elements, the current state
+  int  writable;
+  long value;
+
+  // for simulated enumerated elements, the items
+  int    item_count;
+  char **item_names;
+};
+
+struct alsa_card {
+  int                 num;
+  char               *device;
+  char               *name;
+  snd_ctl_t          *handle;
+  struct pollfd       pfd;
+  GArray             *elems;
+  struct alsa_elem   *sample_capture_elem;
+  struct alsa_elem   *level_meter_elem;
+  GArray             *routing_srcs;
+  GArray             *routing_dsts;
+  GIOChannel         *io_channel;
+  guint               event_source_id;
+  GtkWidget          *window_main;
+  GtkWidget          *window_routing;
+  GtkWidget          *window_mixer;
+  GtkWidget          *window_levels;
+  GtkWidget          *window_startup;
+  GtkWidget          *window_main_contents;
+  GtkWidget          *routing_grid;
+  GtkWidget          *routing_lines;
+  GtkWidget          *routing_hw_in_grid;
+  GtkWidget          *routing_hw_out_grid;
+  GtkWidget          *routing_pcm_in_grid;
+  GtkWidget          *routing_pcm_out_grid;
+  GtkWidget          *routing_mixer_in_grid;
+  GtkWidget          *routing_mixer_out_grid;
+  GtkWidget          *meters[MAX_METERS];
+  guint               meter_gsource_timer;
+  int                 has_speaker_switching;
+  int                 has_talkback;
+  int                 routing_out_count[PC_COUNT];
+  int                 routing_in_count[PC_COUNT];
+  GMenu              *routing_src_menu;
+  GtkWidget          *drag_line;
+  int                 drag_type;
+  struct routing_src *src_drag;
+  struct routing_dst *dst_drag;
+  double              drag_x, drag_y;
+};
+
+// global array of cards
+extern GArray *alsa_cards;
+
+// utility
+void fatal_alsa_error(const char *msg, int err);
+
+// locate elements or get information about them
+struct alsa_elem *get_elem_by_name(GArray *elems, char *name);
+struct alsa_elem *get_elem_by_prefix(GArray *elems, char *prefix);
+int get_max_elem_by_name(GArray *elems, char *prefix, char *needle);
+int is_elem_routing_dst(struct alsa_elem *elem);
+
+// alsa snd_ctl_elem_*() functions
+int alsa_get_elem_type(struct alsa_elem *elem);
+char *alsa_get_elem_name(struct alsa_elem *elem);
+long alsa_get_elem_value(struct alsa_elem *elem);
+int *alsa_get_elem_int_values(struct alsa_elem *elem);
+void alsa_set_elem_value(struct alsa_elem *elem, long value);
+int alsa_get_elem_writable(struct alsa_elem *elem);
+int alsa_get_elem_count(struct alsa_elem *elem);
+int alsa_get_item_count(struct alsa_elem *elem);
+char *alsa_get_item_name(struct alsa_elem *elem, int i);
+
+// add to alsa_cards array
+struct alsa_card *card_create(int card_num);
+
+// scan/rescan for cards
+void alsa_scan_cards(void);
+void alsa_inotify_init(void);