Refactor input method magic numbers into enum

cava.c

@@ -268,7 +268,6 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
 
     char ch = '\0';
     int bars = 25;
-    char supportedInput[255] = "'fifo'";
     int sourceIsAuto = 1;
     double smh;
 
@@ -315,19 +314,6 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
         n = 0;
     }
 
-#ifdef ALSA
-    strcat(supportedInput, ", 'alsa'");
-#endif
-#ifdef PULSE
-    strcat(supportedInput, ", 'pulse'");
-#endif
-#ifdef SNDIO
-    strcat(supportedInput, ", 'sndio'");
-#endif
-#ifdef SHMEM
-    strcat(supportedInput, ", 'shmem'");
-#endif
-
     // general: main loop
     while (1) {
 
@@ -335,7 +321,7 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
         // config: load
         struct error_s error;
         error.length = 0;
-        if (!load_config(configPath, supportedInput, (void *)&p, 0, &error)) {
+        if (!load_config(configPath, &p, 0, &error)) {
             fprintf(stderr, "Error loading config. %s", error.message);
             exit(EXIT_FAILURE);
         }
@@ -388,9 +374,10 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
         audio.treble_index = 0;
 
         debug("starting audio thread\n");
+        switch (p.im) {
 #ifdef ALSA
-        // input_alsa: wait for the input to be ready
+        case INPUT_ALSA:
-        if (p.im == 1) {
+            // input_alsa: wait for the input to be ready
             if (is_loop_device_for_sure(audio.source)) {
                 if (directory_exists("/sys/")) {
                     if (!directory_exists("/sys/module/snd_aloop/")) {
@@ -421,17 +408,15 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
                 }
             }
             debug("got format: %d and rate %d\n", audio.format, audio.rate);
-        }
+            break;
 #endif
-
+        case INPUT_FIFO:
-        if (p.im == 2) {
             // starting fifomusic listener
             thr_id = pthread_create(&p_thread, NULL, input_fifo, (void *)&audio);
             audio.rate = p.fifoSample;
-        }
+            break;
-
 #ifdef PULSE
-        if (p.im == 3) {
+        case INPUT_PULSE:
             if (strcmp(audio.source, "auto") == 0) {
                 getPulseDefaultSink((void *)&audio);
                 sourceIsAuto = 1;
@@ -440,29 +425,30 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
             // starting pulsemusic listener
             thr_id = pthread_create(&p_thread, NULL, input_pulse, (void *)&audio);
             audio.rate = 44100;
-        }
+            break;
 #endif
-
 #ifdef SNDIO
-        if (p.im == 4) {
+        case INPUT_SNDIO:
             thr_id = pthread_create(&p_thread, NULL, input_sndio, (void *)&audio);
             audio.rate = 44100;
-        }
+            break;
 #endif
 
 #ifdef SHMEM
-        if (p.im == 5) {
+        case INPUT_SHMEM:
             thr_id = pthread_create(&p_thread, NULL, input_shmem, (void *)&audio);
             // audio.rate = 44100;
-        }
+            break;
 #endif
-
 #ifdef PORTAUDIO
-        if (p.im == 6) {
+        case INPUT_PORTAUDIO:
             thr_id = pthread_create(&p_thread, NULL, input_portaudio, (void *)&audio);
             audio.rate = 44100;
-        }
+            break;
 #endif
+        default:
+            exit(EXIT_FAILURE); // Can't happen.
+        }
 
         if (p.highcf > audio.rate / 2) {
             cleanup();
@@ -783,7 +769,7 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
                 if (reload_colors) {
                     struct error_s error;
                     error.length = 0;
-                    if (!load_config(configPath, supportedInput, (void *)&p, 1, &error)) {
+                    if (!load_config(configPath, (void *)&p, 1, &error)) {
                         cleanup();
                         fprintf(stderr, "Error loading config. %s", error.message);
                         exit(EXIT_FAILURE);

config.c

@@ -9,7 +9,26 @@
 
 double smoothDef[5] = {1, 1, 1, 1, 1};
 
-char *inputMethod, *outputMethod, *channels;
+char *outputMethod, *channels;
+
+const char *input_method_names[] = {
+    "fifo", "portaudio", "alsa", "pulse", "sndio", "shmem",
+};
+
+const bool has_input_method[] = {
+    true, /** Always have at least FIFO input. */
+    HAS_PORTAUDIO, HAS_ALSA, HAS_PULSE, HAS_SNDIO, HAS_SHMEM,
+};
+
+enum input_method input_method_by_name(const char *str) {
+    for (int i = 0; i < INPUT_MAX; i++) {
+        if (!strcmp(str, input_method_names[i])) {
+            return (enum input_method)i;
+        }
+    }
+
+    return INPUT_MAX;
+}
 
 void write_errorf(void *err, const char *fmt, ...) {
     struct error_s *error = (struct error_s *)err;
@@ -127,55 +146,7 @@ bool validate_colors(void *params, void *err) {
     return true;
 }
 
-bool validate_config(char supportedInput[255], struct config_params *p, struct error_s *error) {
+bool validate_config(struct config_params *p, struct error_s *error) {
-    // validate: input method
-    p->im = 0;
-    if (strcmp(inputMethod, "alsa") == 0) {
-        p->im = 1;
-#ifndef ALSA
-        write_errorf(error, "cava was built without alsa support, install alsa dev files and run "
-                            "make clean && ./configure && make again\n");
-        return false;
-#endif
-    }
-    if (strcmp(inputMethod, "fifo") == 0) {
-        p->im = 2;
-    }
-    if (strcmp(inputMethod, "pulse") == 0) {
-        p->im = 3;
-#ifndef PULSE
-        write_errorf(error, "cava was built without pulseaudio support, install pulseaudio dev "
-                            "files and run make clean && ./configure && make again\n");
-        return false;
-#endif
-    }
-    if (strcmp(inputMethod, "sndio") == 0) {
-        p->im = 4;
-#ifndef SNDIO
-        write_errorf(error, "cava was built without sndio support\n");
-        return false;
-#endif
-    }
-    if (strcmp(inputMethod, "shmem") == 0) {
-        p->im = 5;
-#ifndef SHMEM
-        write_errorf(error, "cava was built without shmem support\n");
-        return false;
-#endif
-    }
-    if (strcmp(inputMethod, "portaudio") == 0) {
-        p->im = 6;
-#ifndef PORTAUDIO
-        write_errorf(error, "cava was built without portaudio support\n");
-        return false;
-#endif
-    }
-    if (p->im == 0) {
-        write_errorf(error, "input method '%s' is not supported, supported methods are: %s\n",
-                     inputMethod, supportedInput);
-        return false;
-    }
-
     // validate: output method
     p->om = 0;
     if (strcmp(outputMethod, "ncurses") == 0) {
@@ -370,8 +341,8 @@ bool load_colors(struct config_params *p, dictionary *ini, void *err) {
     return true;
 }
 
-bool load_config(char configPath[255], char supportedInput[255], struct config_params *p,
+bool load_config(char configPath[255], struct config_params *p, bool colorsOnly,
-                 bool colorsOnly, struct error_s *error) {
+                 struct error_s *error) {
     FILE *fp;
 
     // config: creating path to default config file
@@ -428,24 +399,6 @@ bool load_config(char configPath[255], char supportedInput[255], struct config_p
         return validate_colors(p, error);
     }
 
-    // setting fifo to defaualt if no other input modes supported
-    inputMethod = (char *)iniparser_getstring(ini, "input:method", "fifo");
-
-// setting portaudio to default if supported
-#ifdef ALSA
-    inputMethod = (char *)iniparser_getstring(ini, "input:method", "portaudio");
-#endif
-
-// setting alsa to defaualt if supported
-#ifdef ALSA
-    inputMethod = (char *)iniparser_getstring(ini, "input:method", "alsa");
-#endif
-
-// setting pulse to defaualt if supported
-#ifdef PULSE
-    inputMethod = (char *)iniparser_getstring(ini, "input:method", "pulse");
-#endif
-
 #ifdef NCURSES
     outputMethod = (char *)iniparser_getstring(ini, "output:method", "ncurses");
 #endif
@@ -512,42 +465,66 @@ bool load_config(char configPath[255], char supportedInput[255], struct config_p
 
     free(p->audio_source);
 
-    // config: input
+    char *input_method_name;
-    p->im = 0;
+    for (int i = INPUT_MAX - 1; i >= 0; i--) {
-    if (strcmp(inputMethod, "alsa") == 0) {
+        if (has_input_method[i]) {
-        p->im = 1;
+            input_method_name =
-        p->audio_source = strdup(iniparser_getstring(ini, "input:source", "hw:Loopback,1"));
+                (char *)iniparser_getstring(ini, "input:method", input_method_names[i]);
+        }
     }
-    if (strcmp(inputMethod, "fifo") == 0) {
+
-        p->im = 2;
+    p->im = input_method_by_name(input_method_name);
+    switch (p->im) {
+#ifdef ALSA
+    case INPUT_ALSA:
+        p->audio_source = strdup(iniparser_getstring(ini, "input:source", "hw:Loopback,1"));
+        break;
+#endif
+    case INPUT_FIFO:
         p->audio_source = strdup(iniparser_getstring(ini, "input:source", "/tmp/mpd.fifo"));
         p->fifoSample = iniparser_getint(ini, "input:sample_rate", 44100);
-    }
+        break;
-    if (strcmp(inputMethod, "pulse") == 0) {
+#ifdef PULSE
-        p->im = 3;
+    case INPUT_PULSE:
         p->audio_source = strdup(iniparser_getstring(ini, "input:source", "auto"));
-    }
+        break;
+#endif
 #ifdef SNDIO
-    if (strcmp(inputMethod, "sndio") == 0) {
+    case INPUT_SNDIO:
-        p->im = 4;
         p->audio_source = strdup(iniparser_getstring(ini, "input:source", SIO_DEVANY));
-    }
+        break;
 #endif
 #ifdef SHMEM
-    if (strcmp(inputMethod, "shmem") == 0) {
+    case INPUT_SHMEM:
-        p->im = 5;
         p->audio_source =
             strdup(iniparser_getstring(ini, "input:source", "/squeezelite-00:00:00:00:00:00"));
-    }
+        break;
 #endif
 #ifdef PORTAUDIO
-    if (strcmp(inputMethod, "portaudio") == 0) {
+    case INPUT_PORTAUDIO:
-        p->im = 6;
         p->audio_source = strdup(iniparser_getstring(ini, "input:source", "auto"));
-    }
+        break;
 #endif
+    case INPUT_MAX: {
+        char supported_methods[255] = "";
+        for (int i = 0; i < INPUT_MAX; i++) {
+            if (has_input_method[i]) {
+                strcat(supported_methods, "'");
+                strcat(supported_methods, input_method_names[i]);
+                strcat(supported_methods, "' ");
+            }
+        }
+        write_errorf(error, "input method '%s' is not supported, supported methods are: %s\n",
+                     input_method_name, supported_methods);
+        return false;
+    }
+    default:
+        write_errorf(error, "cava was built without '%s' input support\n",
+                     input_method_names[p->im]);
+        return false;
+    }
 
-    bool result = validate_config(supportedInput, p, error);
+    bool result = validate_config(p, error);
     iniparser_freedict(ini);
     return result;
 }

config.h

@@ -2,9 +2,52 @@
 
 #include <stdbool.h>
 #include <stdio.h>
+#include <string.h>
 
 #define MAX_ERROR_LEN 1024
 
+#ifdef PORTAUDIO
+#define HAS_PORTAUDIO true
+#else
+#define HAS_PORTAUDIO false
+#endif
+
+#ifdef ALSA
+#define HAS_ALSA true
+#else
+#define HAS_ALSA false
+#endif
+
+#ifdef PULSE
+#define HAS_PULSE true
+#else
+#define HAS_PULSE false
+#endif
+
+#ifdef SNDIO
+#define HAS_SNDIO true
+#else
+#define HAS_SNDIO false
+#endif
+
+#ifdef SHMEM
+#define HAS_SHMEM true
+#else
+#define HAS_SHMEM false
+#endif
+
+// These are in order of least-favourable to most-favourable choices, in case
+// multiple are supported and configured.
+enum input_method {
+    INPUT_FIFO,
+    INPUT_PORTAUDIO,
+    INPUT_ALSA,
+    INPUT_PULSE,
+    INPUT_SNDIO,
+    INPUT_SHMEM,
+    INPUT_MAX
+};
+
 struct config_params {
     char *color, *bcolor, *raw_target, *audio_source,
         /**gradient_color_1, *gradient_color_2,*/ **gradient_colors, *data_format, *mono_option;
@@ -12,7 +55,8 @@ struct config_params {
     double monstercat, integral, gravity, ignore, sens;
     unsigned int lowcf, highcf;
     double *smooth;
-    int smcount, customEQ, im, om, col, bgcol, autobars, stereo, is_bin, ascii_range, bit_format,
+    enum input_method im;
+    int smcount, customEQ, om, col, bgcol, autobars, stereo, is_bin, ascii_range, bit_format,
         gradient, gradient_count, fixedbars, framerate, bw, bs, autosens, overshoot, waves,
         FFTbufferSize, fifoSample;
 };
@@ -22,5 +66,5 @@ struct error_s {
     int length;
 };
 
-bool load_config(char configPath[255], char supportedInput[255], struct config_params *p,
+bool load_config(char configPath[255], struct config_params *p, bool colorsOnly,
-                 bool colorsOnly, struct error_s *error);
+                 struct error_s *error);