modules: use calloc() instead of malloc()

In cases where it makes sense, use calloc() instead of malloc():

* When allocating large objects with many members, many for which
  NULL/0 is a good default value.
* Arrays etc where we explicitly initialize to NULL anyway.

module.c

@@ -6,17 +6,9 @@
 struct module *
 module_common_new(void)
 {
-    struct module *mod = malloc(sizeof(*mod));
-    mod->bar = NULL;
+    struct module *mod = calloc(1, sizeof(*mod));
     mtx_init(&mod->lock, mtx_plain);
-    mod->private = NULL;
     mod->destroy = &module_default_destroy;
-
-    /* No defaults for these; must be provided by implementation */
-    mod->run = NULL;
-    mod->content = NULL;
-    mod->refresh_in = NULL;
-
     return mod;
 }
 

modules/alsa.c

@@ -269,13 +269,10 @@ err:
 static struct module *
 alsa_new(const char *card, const char *mixer, struct particle *label)
 {
-    struct private *priv = malloc(sizeof(*priv));
+    struct private *priv = calloc(1, sizeof(*priv));
     priv->label = label;
     priv->card = strdup(card);
     priv->mixer = strdup(mixer);
-    memset(&priv->channels, 0, sizeof(priv->channels));
-    priv->vol_cur = priv->vol_min = priv->vol_max = 0;
-    priv->muted = true;
 
     struct module *mod = module_common_new();
     mod->private = priv;

modules/backlight.c

@@ -206,11 +206,9 @@ run(struct module *mod)
 static struct module *
 backlight_new(const char *device, struct particle *label)
 {
-    struct private *m = malloc(sizeof(*m));
+    struct private *m = calloc(1, sizeof(*m));
     m->label = label;
     m->device = strdup(device);
-    m->max_brightness = 0;
-    m->current_brightness = 0;
 
     struct module *mod = module_common_new();
     mod->private = m;

modules/battery.c

@@ -327,20 +327,11 @@ out:
 static struct module *
 battery_new(const char *battery, struct particle *label, int poll_interval_secs)
 {
-    struct private *m = malloc(sizeof(*m));
+    struct private *m = calloc(1, sizeof(*m));
     m->label = label;
     m->poll_interval = poll_interval_secs;
     m->battery = strdup(battery);
-
-    m->manufacturer = NULL;
-    m->model = NULL;
-
-    m->energy_full_design = 0;
-    m->energy_full = 0;
     m->state = STATE_DISCHARGING;
-    m->capacity = 0;
-    m->energy = 0;
-    m->power = 0;
 
     struct module *mod = module_common_new();
     mod->private = m;

modules/clock.c

@@ -82,7 +82,7 @@ run(struct module *mod)
 static struct module *
 clock_new(struct particle *label, const char *date_format, const char *time_format)
 {
-    struct private *m = malloc(sizeof(*m));
+    struct private *m = calloc(1, sizeof(*m));
     m->label = label;
     m->date_format = strdup(date_format);
     m->time_format = strdup(time_format);

modules/i3.c

@@ -248,7 +248,7 @@ handle_get_workspaces_reply(struct private *m, const struct json_object *json)
 
     size_t count = json_object_array_length(json);
     m->workspaces.count = count;
-    m->workspaces.v = malloc(count * sizeof(m->workspaces.v[0]));
+    m->workspaces.v = calloc(count, sizeof(m->workspaces.v[0]));
 
     for (size_t i = 0; i < count; i++) {
         if (!workspace_from_json(
@@ -709,7 +709,7 @@ static struct module *
 i3_new(struct i3_workspaces workspaces[], size_t workspace_count,
        int left_spacing, int right_spacing)
 {
-    struct private *m = malloc(sizeof(*m));
+    struct private *m = calloc(1, sizeof(*m));
 
     m->left_spacing = left_spacing;
     m->right_spacing = right_spacing;
@@ -722,9 +722,6 @@ i3_new(struct i3_workspaces workspaces[], size_t workspace_count,
         m->ws_content.v[i].content = workspaces[i].content;
     }
 
-    m->workspaces.v = NULL;
-    m->workspaces.count = 0;
-
     struct module *mod = module_common_new();
     mod->private = m;
     mod->run = &run;

modules/label.c

@@ -37,7 +37,7 @@ run(struct module *mod)
 static struct module *
 label_new(struct particle *label)
 {
-    struct private *m = malloc(sizeof(*m));
+    struct private *m = calloc(1, sizeof(*m));
     m->label = label;
 
     struct module *mod = module_common_new();

modules/mpd.c

@@ -565,20 +565,11 @@ refresh_in(struct module *mod, long milli_seconds)
 static struct module *
 mpd_new(const char *host, uint16_t port, struct particle *label)
 {
-    struct private *priv = malloc(sizeof(*priv));
+    struct private *priv = calloc(1, sizeof(*priv));
     priv->host = strdup(host);
     priv->port = port;
     priv->label = label;
-    priv->conn = NULL;
     priv->state = STATE_OFFLINE;
-    priv->repeat = priv->random = priv->consume = false;
-    priv->album = NULL;
-    priv->artist = NULL;
-    priv->title = NULL;
-    priv->elapsed.value = 0;
-    priv->elapsed.when.tv_sec = priv->elapsed.when.tv_nsec = 0;
-    priv->duration = 0;
-    priv->refresh_thread_id = 0;
     priv->refresh_abort_fd = -1;
 
     struct module *mod = module_common_new();

modules/network.c

@@ -511,17 +511,14 @@ run(struct module *mod)
 static struct module *
 network_new(const char *iface, struct particle *label)
 {
-    struct private *priv = malloc(sizeof(*priv));
+    struct private *priv = calloc(1, sizeof(*priv));
     priv->iface = strdup(iface);
     priv->label = label;
 
     priv->nl_sock = -1;
     priv->get_addresses = true;
     priv->ifindex = -1;
-    memset(priv->mac, 0, sizeof(priv->mac));
-    priv->carrier = false;
     priv->state = IF_OPER_DOWN;
-    memset(&priv->addrs, 0, sizeof(priv->addrs));
 
     struct module *mod = module_common_new();
     mod->private = priv;

modules/removables.c

@@ -545,11 +545,10 @@ run(struct module *mod)
 static struct module *
 removables_new(struct particle *label, int left_spacing, int right_spacing)
 {
-    struct private *priv = malloc(sizeof(*priv));
+    struct private *priv = calloc(1, sizeof(*priv));
     priv->label = label;
     priv->left_spacing = left_spacing;
     priv->right_spacing = right_spacing;
-    memset(&priv->devices, 0, sizeof(priv->devices));
 
     struct module *mod = module_common_new();
     mod->private = priv;

modules/xkb.c

@@ -642,16 +642,8 @@ run(struct module *mod)
 static struct module *
 xkb_new(struct particle *label)
 {
-    struct private *m = malloc(sizeof(*m));
+    struct private *m = calloc(1, sizeof(*m));
     m->label = label;
-    m->current = 0;
-    m->layouts.count = 0;
-    m->layouts.layouts = NULL;
-    m->indicators.count = 0;
-    m->indicators.names = NULL;
-    m->caps_lock = false;
-    m->num_lock = false;
-    m->scroll_lock = false;
 
     struct module *mod = module_common_new();
     mod->private = m;