Do not make explicit NULL checks on elements

Most of the NULL checks are actually doubly false logic. Turning the
logic around and removing the NULL check makes the program easier to
read.

src/markup.c

@@ -13,7 +13,7 @@
 
 static char *markup_quote(char *str)
 {
-        assert(str != NULL);
+        assert(str);
 
         str = string_replace_all("&", "&", str);
         str = string_replace_all("\"", """, str);
@@ -26,7 +26,7 @@ static char *markup_quote(char *str)
 
 static char *markup_unquote(char *str)
 {
-        assert(str != NULL);
+        assert(str);
 
         str = string_replace_all(""", "\"", str);
         str = string_replace_all("'", "'", str);
@@ -39,7 +39,7 @@ static char *markup_unquote(char *str)
 
 static char *markup_br2nl(char *str)
 {
-        assert(str != NULL);
+        assert(str);
 
         str = string_replace_all("<br>", "\n", str);
         str = string_replace_all("<br/>", "\n", str);
@@ -230,9 +230,8 @@ void markup_strip_img(char **str, char **urls)
  */
 char *markup_strip(char *str)
 {
-        if (str == NULL) {
+        if (!str)
                 return NULL;
-        }
 
         /* strip all tags */
         string_strip_delimited(str, '<', '>');
@@ -249,9 +248,8 @@ char *markup_strip(char *str)
  */
 char *markup_transform(char *str, enum markup_mode markup_mode)
 {
-        if (str == NULL) {
+        if (!str)
                 return NULL;
-        }
 
         switch (markup_mode) {
         case MARKUP_NULL:

src/menu.c

@@ -193,7 +193,7 @@ void dispatch_menu_result(const char *input)
  */
 void context_menu(void)
 {
-        if (settings.dmenu_cmd == NULL) {
+        if (!settings.dmenu_cmd) {
                 LOG_C("Unable to open dmenu: No dmenu command set.");
                 return;
         }

src/notification.c

@@ -182,7 +182,7 @@ int notification_is_duplicate(const notification *a, const notification *b)
 {
         //Comparing raw icons is not supported, assume they are not identical
         if (settings.icon_position != icons_off
-                && (a->raw_icon != NULL || b->raw_icon != NULL))
+                && (a->raw_icon || b->raw_icon))
                 return false;
 
         return strcmp(a->appname, b->appname) == 0
@@ -579,10 +579,10 @@ void notification_do_action(notification *n)
                 context_menu();
 
         } else if (n->urls) {
-                if (strstr(n->urls, "\n") == NULL)
+                if (strstr(n->urls, "\n"))
-                        open_browser(n->urls);
-                else
                         context_menu();
+                else
+                        open_browser(n->urls);
         }
 }
 

src/option_parser.c

@@ -83,9 +83,8 @@ section_t *get_section(const char *name)
 void add_entry(const char *section_name, const char *key, const char *value)
 {
         section_t *s = get_section(section_name);
-        if (s == NULL) {
+        if (!s)
                 s = new_section(section_name);
-        }
 
         s->entry_count++;
         int len = s->entry_count;
@@ -138,19 +137,19 @@ gint64 ini_get_time(const char *section, const char *key, gint64 def)
 int ini_get_int(const char *section, const char *key, int def)
 {
         const char *value = get_value(section, key);
-        if (value == NULL)
+        if (value)
-                return def;
-        else
                 return atoi(value);
+        else
+                return def;
 }
 
 double ini_get_double(const char *section, const char *key, double def)
 {
         const char *value = get_value(section, key);
-        if (value == NULL)
+        if (value)
-                return def;
-        else
                 return atof(value);
+        else
+                return def;
 }
 
 bool ini_is_set(const char *ini_section, const char *ini_key)
@@ -163,9 +162,8 @@ const char *next_section(const char *section)
         if (section_count == 0)
                 return NULL;
 
-        if (section == NULL) {
+        if (!section)
                 return sections[0].name;
-        }
 
         for (int i = 0; i < section_count; i++) {
                 if (strcmp(section, sections[i].name) == 0) {
@@ -181,9 +179,7 @@ const char *next_section(const char *section)
 int ini_get_bool(const char *section, const char *key, int def)
 {
         const char *value = get_value(section, key);
-        if (value == NULL)
+        if (value) {
-                return def;
-        else {
                 switch (value[0]) {
                 case 'y':
                 case 'Y':
@@ -200,6 +196,8 @@ int ini_get_bool(const char *section, const char *key, int def)
                 default:
                         return def;
                 }
+        } else {
+                return def;
         }
 }
 
@@ -350,10 +348,10 @@ char *cmdline_get_string(const char *key, const char *def, const char *descripti
 
         if (str)
                 return g_strdup(str);
-        if (def == NULL)
+        if (def)
-                return NULL;
-        else
                 return g_strdup(def);
+        else
+                return NULL;
 }
 
 char *cmdline_get_path(const char *key, const char *def, const char *description)
@@ -385,10 +383,10 @@ int cmdline_get_int(const char *key, int def, const char *description)
         cmdline_usage_append(key, "int", description);
         const char *str = cmdline_get_value(key);
 
-        if (str == NULL)
+        if (str)
-                return def;
-        else
                 return atoi(str);
+        else
+                return def;
 }
 
 double cmdline_get_double(const char *key, double def, const char *description)
@@ -396,10 +394,10 @@ double cmdline_get_double(const char *key, double def, const char *description)
         cmdline_usage_append(key, "double", description);
         const char *str = cmdline_get_value(key);
 
-        if (str == NULL)
+        if (str)
-                return def;
-        else
                 return atof(str);
+        else
+                return def;
 }
 
 int cmdline_get_bool(const char *key, int def, const char *description)

src/settings.c

@@ -77,7 +77,7 @@ void load_settings(char *cmdline_config_path)
 
         xdgInitHandle(&xdg);
 
-        if (cmdline_config_path != NULL) {
+        if (cmdline_config_path) {
                 if (0 == strcmp(cmdline_config_path, "-")) {
                         config_file = stdin;
                 } else {
@@ -88,14 +88,14 @@ void load_settings(char *cmdline_config_path)
                         DIE("Cannot find config file: '%s'", cmdline_config_path);
                 }
         }
-        if (config_file == NULL) {
+        if (!config_file) {
                 config_file = xdgConfigOpen("dunst/dunstrc", "r", &xdg);
         }
-        if (config_file == NULL) {
+        if (!config_file) {
                 /* Fall back to just "dunstrc", which was used before 2013-06-23
                  * (before v0.2). */
                 config_file = xdgConfigOpen("dunstrc", "r", &xdg);
-                if (config_file == NULL) {
+                if (!config_file) {
                         LOG_W("No dunstrc found.");
                         xdgWipeHandle(&xdg);
                 }
@@ -669,7 +669,7 @@ void load_settings(char *cmdline_config_path)
                                 r = match;
                 }
 
-                if (r == NULL) {
+                if (!r) {
                         r = g_malloc(sizeof(rule_t));
                         rule_init(r);
                         rules = g_slist_insert(rules, r, -1);
@@ -689,7 +689,7 @@ void load_settings(char *cmdline_config_path)
                                 "markup", NULL
                         );
 
-                        if (c != NULL) {
+                        if (c) {
                                 r->markup = parse_markup_mode(c);
                                 g_free(c);
                         }

src/utils.c

@@ -14,7 +14,7 @@
 char *string_replace_char(char needle, char replacement, char *haystack)
 {
         char *current = haystack;
-        while ((current = strchr(current, needle)) != NULL)
+        while ((current = strchr(current, needle)))
                 *current++ = replacement;
         return haystack;
 }
@@ -49,9 +49,8 @@ char *string_replace(const char *needle, const char *replacement, char *haystack
 {
         char *start;
         start = strstr(haystack, needle);
-        if (start == NULL) {
+        if (!start)
                 return haystack;
-        }
 
         return string_replace_at(haystack, (start - haystack), strlen(needle), replacement);
 }
@@ -70,7 +69,7 @@ char *string_replace_all(const char *needle, const char *replacement, char *hays
         start = strstr(haystack, needle);
         repl_len = strlen(replacement);
 
-        while (start != NULL) {
+        while (start) {
                 needle_pos = start - haystack;
                 haystack = string_replace_at(haystack, needle_pos, needle_len, replacement);
                 start = strstr(haystack + needle_pos + repl_len, needle);

src/x11/screen.c

@@ -46,7 +46,7 @@ static double get_xft_dpi_value(void)
                 XrmInitialize();
                 char *xRMS = XResourceManagerString(xctx.dpy);
 
-                if (xRMS == NULL) {
+                if (!xRMS) {
                         dpi = 0;
                         return 0;
                 }

src/x11/x.c

@@ -815,7 +815,7 @@ static void x_shortcut_ungrab(keyboard_shortcut *ks)
  */
 static void x_shortcut_init(keyboard_shortcut *ks)
 {
-        if (ks == NULL || ks->str == NULL)
+        if (!ks|| !ks->str)
                 return;
 
         if (!strcmp(ks->str, "none") || (!strcmp(ks->str, ""))) {

test/option_parser.c

@@ -279,7 +279,7 @@ TEST test_option_get_bool(void)
 SUITE(suite_option_parser)
 {
         FILE *config_file = fopen("data/test-ini", "r");
-        if (config_file == NULL) {
+        if (!config_file) {
                 fputs("\nTest config file 'data/test-ini' couldn't be opened, failing.\n", stderr);
                 exit(1);
         }