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;
+}