From ae5c0cd3ecb8e53b04edb75d92a52b7eca9d3c15 Mon Sep 17 00:00:00 2001
From: Lauchmelder <robert.altner11@gmail.com>
Date: Sun, 17 Apr 2022 18:31:19 +0200
Subject: [PATCH] added commandline parsing

---
 src/main.c    | 76 ++++++++++++++++++++++++++++++++++++++++++++-------
 src/message.c |  9 ++++++
 src/message.h |  3 +-
 3 files changed, 76 insertions(+), 12 deletions(-)

diff --git a/src/main.c b/src/main.c
index e7096b9..52e3995 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,33 +1,34 @@
-#include <linux/soundcard.h>
 #include <stdio.h>
-#include <fcntl.h>
 #include <unistd.h>
-#include <errno.h>
-#include <string.h>
 #include <stdlib.h>
 #include <pthread.h>
+#include <string.h>
 #include <stdatomic.h>
 #include <sys/time.h>
 
 #include "midi_interface.h"
 #include "midi_parser.h"
 
+typedef struct 
+{
+    const char* midi_file;
+    const char* mapping_file;
+} CommandArguments;
+
 MidiInterface* interface;
 
 static int _Atomic playing = ATOMIC_VAR_INIT(0);
 static uint32_t _Atomic time_per_quarter = ATOMIC_VAR_INIT(1);
 static uint32_t _Atomic current_tick = ATOMIC_VAR_INIT(0);
 
+CommandArguments parse_command_args(int argc, char** argv);
+
 void* play_track(void* data);
 void* advance_counter(void* data);
 
 int main(int argc, char** argv)
 {
-    if(argc != 2)
-    {
-        fprintf(stderr, "Usage: musicalpi <midi file>");
-        exit(-1);
-    }
+    CommandArguments args = parse_command_args(argc, argv);
 
     printf("Loading MIDI file...\n");
     MidiParser* parser;
@@ -106,7 +107,12 @@ void* play_track(void* data)
         {
             time_per_quarter = ((uint32_t*)(event.infos))[0];
         }
-        else if(event.type == MidiNotePressed || event.type == MidiNoteReleased || event.type == MidiControllerValueChanged)
+        else if(
+            event.type == MidiNotePressed || 
+            event.type == MidiNoteReleased || 
+            event.type == MidiControllerValueChanged ||
+            event.type == MidiProgramChanged
+        )
         {
             message->channel = (((uint8_t*)(event.infos))[0] & 0xF);
             message->data = event.infos + 1;
@@ -124,6 +130,13 @@ void* play_track(void* data)
                 case MidiControllerValueChanged:
                     message->type = CONTROLLER_CHANGE;
                     break;
+
+                case MidiProgramChanged:
+                    message->type = PROGRAM_CHANGE;
+                    break;
+
+                default:
+                    break;
             }
             // printf("Sending %d %d\n", message->data[0], message->data[1]);
             int result = write_midi_device(interface, message);
@@ -134,4 +147,47 @@ void* play_track(void* data)
         current_event++;
         tick_of_last_event += event.timeToAppear;
     }
+
+    return NULL;
+}
+
+CommandArguments parse_command_args(int argc, char** argv)
+{
+    CommandArguments parsed_args;
+    parsed_args.midi_file = NULL;
+    parsed_args.mapping_file = NULL;
+
+    int opt;
+    
+    while ((opt = getopt(argc, argv, "hm:")) != -1)
+    {
+        switch(opt)
+        {
+        case 'm':
+        {
+            size_t len = strlen(optarg);
+            parsed_args.mapping_file = (const char*)malloc(len);
+            memcpy((void*)parsed_args.mapping_file, (void*)optarg, len);
+        } break;
+
+        case 'h':
+            fprintf(stderr, "Usage: %s [-m mapping_file] midi_file\n", argv[0]);
+            exit(EXIT_SUCCESS);
+        }
+    }
+
+    if(optind < argc)
+    {
+        size_t len = strlen(argv[optind]);
+        parsed_args.midi_file = (const char*)malloc(len);
+        memcpy((void*)parsed_args.midi_file, (void*)argv[optind], len);
+    }
+
+    if(parsed_args.midi_file == NULL)
+    {
+        fprintf(stderr, "A MIDI file is required\n");
+        exit(EXIT_FAILURE);
+    }
+
+    return parsed_args;
 }
\ No newline at end of file
diff --git a/src/message.c b/src/message.c
index 4398e4b..e91e0ac 100644
--- a/src/message.c
+++ b/src/message.c
@@ -23,6 +23,7 @@ int data_length(MessageType type)
     case NOTE_ON:   return 2;
     case NOTE_OFF:  return 2;
     case CONTROLLER_CHANGE: return 2;
+    case PROGRAM_CHANGE: return 1;
 
     case SYSTEM_EXCLUSIVE: return 0;
     }
@@ -48,6 +49,10 @@ int decode_status_byte(Message* message, uint8_t status)
         message->type = CONTROLLER_CHANGE;
         break;
 
+    case 0xC0:
+        message->type = PROGRAM_CHANGE;
+        break;
+
     case 0xF0:
         message->type = SYSTEM_EXCLUSIVE;
         break;
@@ -78,6 +83,10 @@ int encode_status_byte(const Message* message, uint8_t* status)
         *status |= 0xB0;
         break;
 
+    case PROGRAM_CHANGE:
+        *status |= 0xC0;
+        break;
+
     case SYSTEM_EXCLUSIVE:
         *status |= 0xF0;
         break;
diff --git a/src/message.h b/src/message.h
index da9112e..db53fd5 100644
--- a/src/message.h
+++ b/src/message.h
@@ -5,8 +5,7 @@
 
 typedef enum MessageType
 {
-    NOTE_OFF, NOTE_ON, CONTROLLER_CHANGE,
-    SYSTEM_EXCLUSIVE
+    NOTE_OFF, NOTE_ON, CONTROLLER_CHANGE, PROGRAM_CHANGE, SYSTEM_EXCLUSIVE
 } MessageType;
 
 typedef struct Message