swaybar: Improve i3bar proto implementation

Also reintroduce plaintext fallback for simple status lines.

1 files changed, 134 insertions, 13 deletions

diff --git a/swaybar/main.c b/swaybar/main.c
index e8d26573..1ad5b1cd 100644
--- a/swaybar/main.c
+++ b/swaybar/main.c
@@ -67,6 +67,8 @@ char *output, *status_command;
 struct registry *registry;
 struct window *window;
 bool dirty = true;
+typedef enum {UNDEF, TEXT, I3BAR} command_protocol;
+command_protocol protocol = UNDEF;
 
 struct colors colors = {
         .background = 0x000000FF,
@@ -100,6 +102,20 @@ struct colors colors = {
         },
 };
 
+#define I3JSON_MAXDEPTH 4
+#define I3JSON_UNKNOWN 0
+#define I3JSON_ARRAY 1
+#define I3JSON_STRING 2
+struct {
+        int bufsize;
+        char *buffer;
+        char *line_start;
+        bool escape;
+        int depth;
+        int state[I3JSON_MAXDEPTH+1];
+} i3json_state = { 0, NULL, NULL, false, 0, { I3JSON_UNKNOWN } };
+
+
 void swaybar_teardown() {
         window_teardown(window);
         if (registry) {
@@ -126,7 +142,6 @@ void swaybar_teardown() {
         }
 }
 
-
 void sway_terminate(void) {
         swaybar_teardown();
         exit(EXIT_FAILURE);
@@ -375,10 +390,14 @@ void render() {
         cairo_set_source_u32(window->cairo, colors.statusline);
         int width, height;
 
-        if (status_line) {
+        if (protocol == TEXT) {
+                get_text_size(window, &width, &height, "%s", line);
+                cairo_move_to(window->cairo, window->width - margin - width, margin);
+                pango_printf(window, "%s", line);
+        } else if (protocol == I3BAR && status_line) {
                 int i;
                 int moved = 0;
-                for ( i = status_line->length - 1; i >= 0; --i ) {
+                for (i = status_line->length - 1; i >= 0; --i) {
                         struct status_block *block = status_line->items[i];
                         if (block->full_text) {
                                 get_text_size(window, &width, &height, "%s", block->full_text);
@@ -539,6 +558,81 @@ void parse_json(const char *text) {
         json_object_put(results);
 }
 
+int i3json_handle(FILE *file) {
+        char *c;
+        int handled = 0;
+        // handle partially buffered data
+        // make sure 1023+1 bytes at the end are free
+        if (i3json_state.line_start) {
+                int len = strlen(i3json_state.line_start);
+                memmove(i3json_state.buffer, i3json_state.line_start, len+1);
+                if (i3json_state.bufsize < len+1024) {
+                        i3json_state.bufsize += 1024;
+                        i3json_state.buffer = realloc(i3json_state.buffer, i3json_state.bufsize);
+                }
+                c = i3json_state.buffer+len;
+                i3json_state.line_start = i3json_state.buffer;
+        } else if (!i3json_state.buffer) {
+                i3json_state.buffer = malloc(1024);
+                i3json_state.bufsize = 1024;
+                c = i3json_state.buffer;
+        } else {
+                c = i3json_state.buffer;
+        }
+        if (!i3json_state.buffer) {
+                sway_abort("Could not allocate buffer.");
+        }
+        // get fresh data at the end of the buffer
+        if (!fgets(c, 1023, file)) return -1;
+        c[1023] = '\0';
+
+        while (*c) {
+                if (i3json_state.state[i3json_state.depth] == I3JSON_STRING) {
+                        if (!i3json_state.escape && *c == '"') {
+                                --i3json_state.depth;
+                        }
+                        i3json_state.escape = !i3json_state.escape && *c == '\\';
+                } else {
+                        switch (*c) {
+                        case '[':
+                                ++i3json_state.depth;
+                                if (i3json_state.depth > I3JSON_MAXDEPTH) {
+                                        sway_abort("JSON too deep");
+                                }
+                                i3json_state.state[i3json_state.depth] = I3JSON_ARRAY;
+                                if (i3json_state.depth == 2) {
+                                        i3json_state.line_start = c;
+                                }
+                                break;
+                        case ']':
+                                if (i3json_state.state[i3json_state.depth] != I3JSON_ARRAY) {
+                                        sway_abort("JSON malformed");
+                                }
+                                --i3json_state.depth;
+                                if (i3json_state.depth == 1) {
+                                        ssize_t len = c-i3json_state.line_start+1;
+                                        char p = c[len];
+                                        c[len] = '\0';
+                                        parse_json(i3json_state.line_start);
+                                        c[len] = p;
+                                        ++handled;
+                                        i3json_state.line_start = c+1;
+                                }
+                                break;
+                        case '"':
+                                ++i3json_state.depth;
+                                if (i3json_state.depth > I3JSON_MAXDEPTH) {
+                                        sway_abort("JSON too deep");
+                                }
+                                i3json_state.state[i3json_state.depth] = I3JSON_STRING;
+                                break;
+                        }
+                }
+                ++c;
+        }
+        return handled;
+}
+
 void poll_for_update() {
         fd_set readfds;
         int activity;
@@ -574,17 +668,43 @@ void poll_for_update() {
 
                 if (status_command && FD_ISSET(pipefd[0], &readfds)) {
                         sway_log(L_DEBUG, "Got update from status command.");
-                        fgets(line, sizeof(line), command);
-                        sway_log(L_DEBUG, "zzz %s", line);
-                        int l = strlen(line) - 1;
-                        if (line[l] == '\n') {
-                                line[l] = '\0';
+                        int linelen;
+                        switch (protocol) {
+                        case I3BAR:
+                                sway_log(L_DEBUG, "Got i3bar protocol.");
+                                if (i3json_handle(command) > 0) {
+                                        dirty = true;
+                                }
+                                break;
+                        case TEXT:
+                        case UNDEF:
+                                sway_log(L_DEBUG, "Got text protocol.");
+                                fgets(line, sizeof(line), command);
+                                linelen = strlen(line) - 1;
+                                if (line[linelen] == '\n') {
+                                        line[linelen] = '\0';
+                                }
+                                dirty = true;
+                                if (protocol == UNDEF) {
+                                        protocol = TEXT;
+                                        if (line[0] == '{') {
+                                                // detect i3bar json protocol
+                                                json_object *proto = json_tokener_parse(line);
+                                                json_object *version;
+                                                if (proto) {
+                                                        if (json_object_object_get_ex(proto, "version", &version)
+                                                                                && json_object_get_int(version) == 1
+                                                        ) {
+                                                                sway_log(L_DEBUG, "Switched to i3bar protocol.");
+                                                                protocol = I3BAR;
+                                                                line[0] = '\0';
+                                                        }
+                                                        json_object_put(proto);
+                                                }
+                                        }
+                                }
+                                break;
                         }
-                        if (line[0] == ',') {
-                                line[0] = ' ';
-                        }
-                        dirty = true;
-                        parse_json(line);
                 }
         }
 }
@@ -681,6 +801,7 @@ int main(int argc, char **argv) {
 
                 close(pipefd[1]);
                 command = fdopen(pipefd[0], "r");
+                setbuf(command, NULL);
                 line[0] = '\0';
         }