tray: better errors when parsing index.theme

1 files changed, 90 insertions, 60 deletions

diff --git a/swaybar/tray/icon.c b/swaybar/tray/icon.c
index d0c3fa56..9c62911d 100644
--- a/swaybar/tray/icon.c
+++ b/swaybar/tray/icon.c
@@ -14,6 +14,10 @@
 #include "log.h"
 #include "stringop.h"
 
+static int cmp_id(const void *item, const void *cmp_to) {
+        return strcmp(item, cmp_to);
+}
+
 static bool dir_exists(char *path) {
         struct stat sb;
         return stat(path, &sb) == 0 && S_ISDIR(sb.st_mode);
@@ -78,35 +82,37 @@ static void destroy_theme(struct icon_theme *theme) {
         free(theme);
 }
 
-static int cmp_group(const void *item, const void *cmp_to) {
-        return strcmp(item, cmp_to);
-}
-
-static bool validate_icon_theme(struct icon_theme *theme) {
-        return theme && theme->name && theme->comment && theme->directories;
-}
-
-static bool group_handler(char *old_group, char *new_group,
+static const char *group_handler(char *old_group, char *new_group,
                 struct icon_theme *theme) {
-        if (!old_group) { // first group must be "Icon Theme"
-                if (!new_group) {
-                        return true;
-                }
-                return strcmp(new_group, "Icon Theme") != 0;
+        if (!old_group) {
+                return new_group && strcmp(new_group, "Icon Theme") == 0 ? NULL :
+                        "first group must be 'Icon Theme'";
         }
 
         if (strcmp(old_group, "Icon Theme") == 0) {
-                if (!validate_icon_theme(theme)) {
-                        return true;
+                if (!theme->name) {
+                        return "missing required key 'Name'";
+                } else if (!theme->comment) {
+                        return "missing required key 'Comment'";
+                } else if (!theme->directories) {
+                        return "missing required key 'Directories'";
+                } else {
+                        for (char *c = theme->name; *c; ++c) {
+                                if (*c == ',' || *c == ' ') {
+                                        return "malformed theme name";
+                                }
+                        }
                 }
         } else {
                 if (theme->subdirs->length == 0) { // skip
-                        return false;
+                        return NULL;
                 }
 
                 struct icon_theme_subdir *subdir =
                         theme->subdirs->items[theme->subdirs->length - 1];
-                if (!subdir->size) return true;
+                if (!subdir->size) {
+                        return "missing required key 'Size'";
+                }
 
                 switch (subdir->type) {
                 case FIXED: subdir->max_size = subdir->min_size = subdir->size;
@@ -122,20 +128,20 @@ static bool group_handler(char *old_group, char *new_group,
                 }
         }
 
-        if (new_group && list_seq_find(theme->directories, cmp_group, new_group) != -1) {
+        if (new_group && list_seq_find(theme->directories, cmp_id, new_group) != -1) {
                 struct icon_theme_subdir *subdir = calloc(1, sizeof(struct icon_theme_subdir));
                 if (!subdir) {
-                        return true;
+                        return "out of memory";
                 }
                 subdir->name = strdup(new_group);
                 subdir->threshold = 2;
                 list_add(theme->subdirs, subdir);
         }
 
-        return false;
+        return NULL;
 }
 
-static int entry_handler(char *group, char *key, char *value,
+static const char *entry_handler(char *group, char *key, char *value,
                 struct icon_theme *theme) {
         if (strcmp(group, "Icon Theme") == 0) {
                 if (strcmp(key, "Name") == 0) {
@@ -149,20 +155,17 @@ static int entry_handler(char *group, char *key, char *value,
                 } // Ignored: ScaledDirectories, Hidden, Example
         } else {
                 if (theme->subdirs->length == 0) { // skip
-                        return false;
+                        return NULL;
                 }
 
                 struct icon_theme_subdir *subdir =
                         theme->subdirs->items[theme->subdirs->length - 1];
                 if (strcmp(subdir->name, group) != 0) { // skip
-                        return false;
+                        return NULL;
                 }
 
-                char *end;
-                int n = strtol(value, &end, 10);
-                if (strcmp(key, "Size") == 0) {
-                        subdir->size = n;
-                        return *end != '\0';
+                if (strcmp(key, "Context") == 0) {
+                        return NULL; // ignored, but explicitly handled to not fail parsing
                 } else if (strcmp(key, "Type") == 0) {
                         if (strcmp(value, "Fixed") == 0) {
                                 subdir->type = FIXED;
@@ -171,20 +174,28 @@ static int entry_handler(char *group, char *key, char *value,
                         } else if (strcmp(value, "Threshold") == 0) {
                                 subdir->type = THRESHOLD;
                         } else {
-                                return true;
+                                return "invalid value - expected 'Fixed', 'Scalable' or 'Threshold'";
                         }
+                        return NULL;
+                }
+
+                char *end;
+                int n = strtol(value, &end, 10);
+                if (*end != '\0') {
+                        return "invalid value - expected a number";
+                }
+
+                if (strcmp(key, "Size") == 0) {
+                        subdir->size = n;
                 } else if (strcmp(key, "MaxSize") == 0) {
                         subdir->max_size = n;
-                        return *end != '\0';
                 } else if (strcmp(key, "MinSize") == 0) {
                         subdir->min_size = n;
-                        return *end != '\0';
                 } else if (strcmp(key, "Threshold") == 0) {
                         subdir->threshold = n;
-                        return *end != '\0';
-                } // Ignored: Scale, Applications
+                } // Ignored: Scale
         }
-        return false;
+        return NULL;
 }
 
 /*
@@ -215,12 +226,16 @@ static struct icon_theme *read_theme_file(char *basedir, char *theme_name) {
         }
         theme->subdirs = create_list();
 
-        bool error = false;
-        char *group = NULL;
+        list_t *groups = create_list();
+
+        const char *error = NULL;
+        int line_no = 0;
         char *full_line = NULL;
         size_t full_len = 0;
         ssize_t nread;
         while ((nread = getline(&full_line, &full_len, theme_file)) != -1) {
+                ++line_no;
+
                 char *line = full_line - 1;
                 while (isspace(*++line)) {} // remove leading whitespace
                 if (!*line || line[0] == '#') continue; // ignore blank lines & comments
@@ -231,37 +246,42 @@ static struct icon_theme *read_theme_file(char *basedir, char *theme_name) {
 
                 if (line[0] == '[') { // group header
                         // check well-formed
-                        if (line[--len] != ']') {
-                                error = true;
-                                break;
-                        }
                         int i = 1;
                         for (; !iscntrl(line[i]) && line[i] != '[' && line[i] != ']'; ++i) {}
-                        if (i < len) {
-                                error = true;
+                        if (i != --len || line[i] != ']') {
+                                error = "malformed group header";
                                 break;
                         }
 
-                        // call handler
                         line[len] = '\0';
-                        error = group_handler(group, &line[1], theme);
+
+                        // check group is not duplicate
+                        if (list_seq_find(groups, cmp_id, &line[1]) != -1) {
+                                error = "duplicate group";
+                                break;
+                        }
+
+                        // call handler
+                        char *last_group = groups->length > 0 ? groups->items[groups->length - 1] : NULL;
+                        error = group_handler(last_group, &line[1], theme);
                         if (error) {
                                 break;
                         }
-                        free(group);
-                        group = strdup(&line[1]);
+
+                        list_add(groups, strdup(&line[1]));
                 } else { // key-value pair
-                        if (!group) {
-                                error = true;
+                        if (groups->length == 0) {
+                                error = "unexpected content before first header";
                                 break;
                         }
+
                         // check well-formed
                         int eok = 0;
                         for (; isalnum(line[eok]) || line[eok] == '-'; ++eok) {} // TODO locale?
                         int i = eok - 1;
                         while (isspace(line[++i])) {}
                         if (line[i] != '=') {
-                                error = true;
+                                error = "malformed key-value pair";
                                 break;
                         }
 
@@ -269,28 +289,38 @@ static struct icon_theme *read_theme_file(char *basedir, char *theme_name) {
                         char *value = &line[i];
                         while (isspace(*++value)) {}
                         // TODO unescape value
-                        error = entry_handler(group, line, value, theme);
+
+                        error = entry_handler(groups->items[groups->length - 1], line,
+                                        value, theme);
                         if (error) {
                                 break;
                         }
                 }
         }
 
-        if (!error && group) {
-                error = group_handler(group, NULL, theme);
+        if (!error) {
+                if (groups->length > 0) {
+                        error = group_handler(groups->items[groups->length - 1], NULL, theme);
+                } else {
+                        error = "empty file";
+                }
         }
 
-        free(group);
-        free(full_line);
-        fclose(theme_file);
-
-        if (!error && validate_icon_theme(theme)) {
+        if (!error) {
                 theme->dir = strdup(theme_name);
-                return theme;
         } else {
+                char *last_group = groups->length > 0 ? groups->items[groups->length-1] : "n/a";
+                sway_log(SWAY_DEBUG, "Failed to load theme '%s' - parsing of file "
+                                "'%s/%s/index.theme' failed on line %d (group '%s'): %s",
+                                theme_name, basedir, theme_name, line_no, last_group, error);
                 destroy_theme(theme);
-                return NULL;
+                theme = NULL;
         }
+
+        free(full_line);
+        list_free_items_and_destroy(groups);
+        fclose(theme_file);
+        return theme;
 }
 
 static list_t *load_themes_in_dir(char *basedir) {