swaybar: implement icon themes and lookup for tray

1 files changed, 462 insertions, 0 deletions

diff --git a/swaybar/tray/icon.c b/swaybar/tray/icon.c
new file mode 100644
index 00000000..67805858
--- /dev/null
+++ b/swaybar/tray/icon.c
@@ -0,0 +1,462 @@
+#define _POSIX_C_SOURCE 200809L
+#include <ctype.h>
+#include <dirent.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <wordexp.h>
+#include "swaybar/tray/icon.h"
+#include "config.h"
+#include "list.h"
+#include "log.h"
+#include "stringop.h"
+
+static bool dir_exists(char *path) {
+        struct stat sb;
+        return stat(path, &sb) == 0 && S_ISDIR(sb.st_mode);
+}
+
+static list_t *get_basedirs(void) {
+        list_t *basedirs = create_list();
+        list_add(basedirs, strdup("$HOME/.icons")); // deprecated
+
+        char *data_home = getenv("XDG_DATA_HOME");
+        list_add(basedirs, strdup(data_home && *data_home ?
+                        "$XDG_DATA_HOME/icons" : "$HOME/.local/share/icons"));
+
+        list_add(basedirs, strdup("/usr/share/pixmaps"));
+
+        char *data_dirs = getenv("XDG_DATA_DIRS");
+        if (!(data_dirs && *data_dirs)) {
+                data_dirs = "/usr/local/share:/usr/share";
+        }
+        data_dirs = strdup(data_dirs);
+        char *dir = strtok(data_dirs, ":");
+        do {
+                size_t path_len = snprintf(NULL, 0, "%s/icons", dir) + 1;
+                char *path = malloc(path_len);
+                snprintf(path, path_len, "%s/icons", dir);
+                list_add(basedirs, path);
+        } while ((dir = strtok(NULL, ":")));
+        free(data_dirs);
+
+        list_t *basedirs_expanded = create_list();
+        for (int i = 0; i < basedirs->length; ++i) {
+                wordexp_t p;
+                if (wordexp(basedirs->items[i], &p, WRDE_UNDEF) == 0) {
+                        if (dir_exists(p.we_wordv[0])) {
+                                list_add(basedirs_expanded, strdup(p.we_wordv[0]));
+                        }
+                        wordfree(&p);
+                }
+        }
+
+        list_free_items_and_destroy(basedirs);
+
+        return basedirs_expanded;
+}
+
+static void destroy_theme(struct icon_theme *theme) {
+        if (!theme) {
+                return;
+        }
+        free(theme->name);
+        free(theme->comment);
+        free(theme->inherits);
+        list_free_items_and_destroy(theme->directories);
+        free(theme->dir);
+
+        for (int i = 0; i < theme->subdirs->length; ++i) {
+                struct icon_theme_subdir *subdir = theme->subdirs->items[i];
+                free(subdir->name);
+                free(subdir);
+        }
+        list_free(theme->subdirs);
+        free(theme);
+}
+
+static int cmp_group(const void *item, const void *cmp_to) {
+        return strcmp(item, cmp_to);
+}
+
+static bool group_handler(char *old_group, char *new_group,
+                struct icon_theme *theme) {
+        if (!old_group) { // first group must be "Icon Theme"
+                return strcmp(new_group, "Icon Theme");
+        }
+
+        if (strcmp(old_group, "Icon Theme") == 0) {
+                if (!(theme->name && theme->comment && theme->directories)) {
+                        return true;
+                }
+        } else {
+                if (theme->subdirs->length == 0) { // skip
+                        return false;
+                }
+
+                struct icon_theme_subdir *subdir =
+                        theme->subdirs->items[theme->subdirs->length - 1];
+                if (!subdir->size) return true;
+
+                switch (subdir->type) {
+                case FIXED: subdir->max_size = subdir->min_size = subdir->size;
+                        break;
+                case SCALABLE: {
+                        if (!subdir->max_size) subdir->max_size = subdir->size;
+                        if (!subdir->min_size) subdir->min_size = subdir->size;
+                        break;
+                }
+                case THRESHOLD:
+                        subdir->max_size = subdir->size + subdir->threshold;
+                        subdir->min_size = subdir->size - subdir->threshold;
+                }
+        }
+
+        if (new_group && list_seq_find(theme->directories, cmp_group, new_group) != -1) {
+                struct icon_theme_subdir *subdir = calloc(1, sizeof(struct icon_theme_subdir));
+                if (!subdir) {
+                        return true;
+                }
+                subdir->name = strdup(new_group);
+                subdir->threshold = 2;
+                list_add(theme->subdirs, subdir);
+        }
+
+        return false;
+}
+
+static int entry_handler(char *group, char *key, char *value,
+                struct icon_theme *theme) {
+        if (strcmp(group, "Icon Theme") == 0) {
+                if (strcmp(key, "Name") == 0) {
+                        theme->name = strdup(value);
+                } else if (strcmp(key, "Comment") == 0) {
+                        theme->comment = strdup(value);
+                } else if (strcmp(key, "Inherists") == 0) {
+                        theme->inherits = strdup(value);
+                } else if (strcmp(key, "Directories") == 0) {
+                        theme->directories = split_string(value, ",");
+                } // Ignored: ScaledDirectories, Hidden, Example
+        } else {
+                if (theme->subdirs->length == 0) { // skip
+                        return false;
+                }
+
+                struct icon_theme_subdir *subdir =
+                        theme->subdirs->items[theme->subdirs->length - 1];
+                if (strcmp(subdir->name, group) != 0) { // skip
+                        return false;
+                }
+
+                char *end;
+                int n = strtol(value, &end, 10);
+                if (strcmp(key, "Size") == 0) {
+                        subdir->size = n;
+                        return *end != '\0';
+                } else if (strcmp(key, "Type") == 0) {
+                        if (strcmp(value, "Fixed") == 0) {
+                                subdir->type = FIXED;
+                        } else if (strcmp(value, "Scalable") == 0) {
+                                subdir->type = SCALABLE;
+                        } else if (strcmp(value, "Threshold") == 0) {
+                                subdir->type = THRESHOLD;
+                        } else {
+                                return true;
+                        }
+                } 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
+        }
+        return false;
+}
+
+/*
+ * This is a Freedesktop Desktop Entry parser (essentially INI)
+ * It calls entry_handler for every entry
+ * and group_handler between every group (as well as at both ends)
+ * Handlers return whether an error occured, which stops parsing
+ */
+static struct icon_theme *read_theme_file(char *basedir, char *theme_name) {
+        // look for index.theme file
+        size_t path_len = snprintf(NULL, 0, "%s/%s/index.theme", basedir,
+                        theme_name) + 1;
+        char *path = malloc(path_len);
+        snprintf(path, path_len, "%s/%s/index.theme", basedir, theme_name);
+        FILE *theme_file = fopen(path, "r");
+        if (!theme_file) {
+                return NULL;
+        }
+
+        struct icon_theme *theme = calloc(1, sizeof(struct icon_theme));
+        if (!theme) {
+                return NULL;
+        }
+        theme->subdirs = create_list();
+
+        bool error = false;
+        char *group = NULL;
+        char *full_line = NULL;
+        size_t full_len = 0;
+        ssize_t nread;
+        while ((nread = getline(&full_line, &full_len, theme_file)) != -1) {
+                char *line = full_line - 1;
+                while (isspace(*++line)) {} // remove leading whitespace
+                if (!*line || line[0] == '#') continue; // ignore blank lines & comments
+
+                int len = nread - (line - full_line);
+                while (isspace(line[--len])) {}
+                line[++len] = '\0'; // remove trailing whitespace
+
+                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;
+                                break;
+                        }
+
+                        // call handler
+                        line[len] = '\0';
+                        error = group_handler(group, &line[1], theme);
+                        if (error) {
+                                break;
+                        }
+                        free(group);
+                        group = strdup(&line[1]);
+                } else { // key-value pair
+                        // 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;
+                                break;
+                        }
+
+                        line[eok] = '\0'; // split into key-value pair
+                        char *value = &line[i];
+                        while (isspace(*++value)) {}
+                        // TODO unescape value
+                        error = entry_handler(group, line, value, theme);
+                        if (error) {
+                                break;
+                        }
+                }
+        }
+
+        if (!error && group) {
+                error = group_handler(group, NULL, theme);
+        }
+
+        free(group);
+        free(full_line);
+        fclose(theme_file);
+
+        if (!error) {
+                theme->dir = strdup(theme_name);
+                return theme;
+        } else {
+                destroy_theme(theme);
+                return NULL;
+        }
+}
+
+static list_t *load_themes_in_dir(char *basedir) {
+        DIR *dir;
+        if (!(dir = opendir(basedir))) {
+                return NULL;
+        }
+
+        list_t *themes = create_list();
+        struct dirent *entry;
+        while ((entry = readdir(dir))) {
+                if (entry->d_name[0] == '.') continue;
+
+                struct icon_theme *theme = read_theme_file(basedir, entry->d_name);
+                if (theme) {
+                        list_add(themes, theme);
+                }
+        }
+        return themes;
+}
+
+void init_themes(list_t **themes, list_t **basedirs) {
+        *basedirs = get_basedirs();
+
+        *themes = create_list();
+        for (int i = 0; i < (*basedirs)->length; ++i) {
+                list_t *dir_themes = load_themes_in_dir((*basedirs)->items[i]);
+                list_cat(*themes, dir_themes);
+                list_free(dir_themes);
+        }
+
+        list_t *theme_names = create_list();
+        for (int i = 0; i < (*themes)->length; ++i) {
+                struct icon_theme *theme = (*themes)->items[i];
+                list_add(theme_names, theme->name);
+        }
+        wlr_log(WLR_DEBUG, "Loaded themes: %s", join_list(theme_names, ", "));
+        list_free(theme_names);
+}
+
+void finish_themes(list_t *themes, list_t *basedirs) {
+        for (int i = 0; i < themes->length; ++i) {
+                destroy_theme(themes->items[i]);
+        }
+        list_free(themes);
+        list_free_items_and_destroy(basedirs);
+}
+
+static char *find_icon_in_subdir(char *name, char *basedir, char *theme,
+                char *subdir) {
+        static const char *extensions[] = {
+#if HAVE_GDK_PIXBUF
+                "svg",
+#endif
+                "png",
+#if HAVE_GDK_PIXBUF
+                "xpm"
+#endif
+        };
+
+        size_t path_len = snprintf(NULL, 0, "%s/%s/%s/%s.EXT", basedir, theme,
+                        subdir, name) + 1;
+        char *path = malloc(path_len);
+
+        for (size_t i = 0; i < sizeof(extensions) / sizeof(*extensions); ++i) {
+                snprintf(path, path_len, "%s/%s/%s/%s.%s", basedir, theme, subdir,
+                                name, extensions[i]);
+                if (access(path, R_OK) == 0) {
+                        return path;
+                }
+        }
+
+        free(path);
+        return NULL;
+}
+
+static bool theme_exists_in_basedir(char *theme, char *basedir) {
+        size_t path_len = snprintf(NULL, 0, "%s/%s", basedir, theme) + 1;
+        char *path = malloc(path_len);
+        snprintf(path, path_len, "%s/%s", basedir, theme);
+        bool ret = dir_exists(path);
+        free(path);
+        return ret;
+}
+
+static char *find_icon_with_theme(list_t *basedirs, list_t *themes, char *name,
+                int size, char *theme_name, int *min_size, int *max_size) {
+        struct icon_theme *theme = NULL;
+        for (int i = 0; i < themes->length; ++i) {
+                theme = themes->items[i];
+                if (strcmp(theme->name, theme_name) == 0) {
+                        break;
+                }
+                theme = NULL;
+        }
+        if (!theme) return NULL;
+
+        char *icon = NULL;
+        for (int i = 0; i < basedirs->length; ++i) {
+                if (!theme_exists_in_basedir(theme->dir, basedirs->items[i])) {
+                        continue;
+                }
+                // search backwards to hopefully hit scalable/larger icons first
+                for (int j = theme->subdirs->length - 1; j >= 0; --j) {
+                        struct icon_theme_subdir *subdir = theme->subdirs->items[j];
+                        if (size >= subdir->min_size && size <= subdir->max_size) {
+                                if ((icon = find_icon_in_subdir(name, basedirs->items[i],
+                                                                theme->dir, subdir->name))) {
+                                        *min_size = subdir->min_size;
+                                        *max_size = subdir->max_size;
+                                        return icon;
+                                }
+                        }
+                }
+        }
+
+        // inexact match
+        unsigned smallest_error = -1; // UINT_MAX
+        for (int i = 0; i < basedirs->length; ++i) {
+                if (!theme_exists_in_basedir(theme->dir, basedirs->items[i])) {
+                        continue;
+                }
+                for (int j = theme->subdirs->length - 1; j >= 0; --j) {
+                        struct icon_theme_subdir *subdir = theme->subdirs->items[j];
+                        unsigned error = (size > subdir->max_size ? size - subdir->max_size : 0)
+                                + (size < subdir->min_size ? subdir->min_size - size : 0);
+                        if (error < smallest_error) {
+                                char *test_icon = find_icon_in_subdir(name, basedirs->items[i],
+                                                theme->dir, subdir->name);
+                                if (test_icon) {
+                                        icon = test_icon;
+                                        smallest_error = error;
+                                        *min_size = subdir->min_size;
+                                        *max_size = subdir->max_size;
+                                }
+                        }
+                }
+        }
+
+        if (!icon && theme->inherits) {
+                icon = find_icon_with_theme(basedirs, themes, name, size,
+                                theme->inherits, min_size, max_size);
+        }
+
+        return icon;
+}
+
+char *find_icon_in_dir(char *name, char *dir, int *min_size, int *max_size) {
+        char *icon = find_icon_in_subdir(name, dir, "", "");
+        if (icon) {
+                *min_size = 1;
+                *max_size = 512;
+        }
+        return icon;
+
+}
+
+static char *find_fallback_icon(list_t *basedirs, char *name, int *min_size,
+                int *max_size) {
+        for (int i = 0; i < basedirs->length; ++i) {
+                char *icon = find_icon_in_dir(name, basedirs->items[i], min_size, max_size);
+                if (icon) {
+                        return icon;
+                }
+        }
+        return NULL;
+}
+
+char *find_icon(list_t *themes, list_t *basedirs, char *name, int size,
+                char *theme, int *min_size, int *max_size) {
+        // TODO https://specifications.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html#implementation_notes
+        char *icon = NULL;
+        if (theme) {
+                icon = find_icon_with_theme(basedirs, themes, name, size, theme,
+                                min_size, max_size);
+        }
+        if (!icon) {
+                icon = find_icon_with_theme(basedirs, themes, name, size, "Hicolor",
+                                min_size, max_size);
+        }
+        if (!icon) {
+                icon = find_fallback_icon(basedirs, name, min_size, max_size);
+        }
+        return icon;
+}