Demarcate i3bar JSON into individual updates

1 files changed, 88 insertions, 0 deletions

diff --git a/swaybar/i3bar.c b/swaybar/i3bar.c
new file mode 100644
index 00000000..5be348b2
--- /dev/null
+++ b/swaybar/i3bar.c
@@ -0,0 +1,88 @@
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <wlr/util/log.h>
+#include "swaybar/config.h"
+#include "swaybar/status_line.h"
+
+static void i3bar_parse_json(struct status_line *status, const char *text) {
+	wlr_log(L_DEBUG, "got json: %s", text);
+}
+
+int i3bar_readable(struct status_line *status) {
+	struct i3bar_protocol_state *state = &status->i3bar_state;
+
+	char *cur = &state->buffer[state->buffer_index];
+	ssize_t n = read(status->read_fd, cur,
+			state->buffer_size - state->buffer_index);
+	if (n == 0) {
+		return 0;
+	}
+
+	if (n == (ssize_t)(state->buffer_size - state->buffer_index)) {
+		state->buffer_size = state->buffer_size * 2;
+		char *new_buffer = realloc(state->buffer, state->buffer_size);
+		if (!new_buffer) {
+			free(state->buffer);
+			status_error(status, "[failed to allocate buffer]");
+			return -1;
+		}
+		state->buffer = new_buffer;
+	}
+
+	int handled = 0;
+	while (*cur) {
+		if (state->nodes[state->depth] == JSON_NODE_STRING) {
+			if (!state->escape && *cur == '"') {
+				--state->depth;
+			}
+			state->escape = !state->escape && *cur == '\\';
+		} else {
+			switch (*cur) {
+			case '[':
+				++state->depth;
+				if (state->depth >
+						sizeof(state->nodes) / sizeof(state->nodes[0])) {
+					status_error(status, "[i3bar json too deep]");
+					return -1;
+				}
+				state->nodes[state->depth] = JSON_NODE_ARRAY;
+				if (state->depth == 1) {
+					state->current_node = cur;
+				}
+				break;
+			case ']':
+				if (state->nodes[state->depth] != JSON_NODE_ARRAY) {
+					status_error(status, "[failed to parse i3bar json]");
+					return -1;
+				}
+				--state->depth;
+				if (state->depth == 0) {
+					// cur[1] is valid since cur[0] != '\0'
+					char p = cur[1];
+					cur[1] = '\0';
+					i3bar_parse_json(status, state->current_node);
+					cur[1] = p;
+					memmove(state->buffer, cur,
+							state->buffer_size - (cur - state->buffer));
+					++handled;
+					cur = state->buffer;
+					state->current_node = cur + 1;
+				}
+				break;
+			case '"':
+				++state->depth;
+				if (state->depth >
+						sizeof(state->nodes) / sizeof(state->nodes[0])) {
+					status_error(status, "[i3bar json too deep]");
+					return -1;
+				}
+				state->nodes[state->depth] = JSON_NODE_STRING;
+				break;
+			}
+		}
+		++cur;
+	}
+	state->buffer_index = cur - state->buffer;
+	return handled;
+}