1 files changed, 143 insertions, 0 deletions
diff --git a/plugins/packet_radio/tnc_host.c b/plugins/packet_radio/tnc_host.c
new file mode 100644
index 0000000..8700e61
--- /dev/null
+++ b/plugins/packet_radio/tnc_host.c
@@ -0,0 +1,143 @@
+#include "tnc_host.h"
+
+#include <ctype.h>
+#include <string.h>
+
+void hybbx_tnc_host_init(hybbx_tnc_host_t *host,
+                         hybbx_tnc_host_text_cb text_cb,
+                         hybbx_tnc_host_event_cb event_cb,
+                         void *userdata)
+{
+    if (host == NULL) {
+        return;
+    }
+
+    memset(host, 0, sizeof(*host));
+    host->state = HYBBX_TNC_HOST_BOOT;
+    host->text_cb = text_cb;
+    host->event_cb = event_cb;
+    host->userdata = userdata;
+}
+
+void hybbx_tnc_host_reset(hybbx_tnc_host_t *host)
+{
+    if (host == NULL) {
+        return;
+    }
+
+    host->line_len = 0;
+    host->line[0] = '\0';
+    host->state = HYBBX_TNC_HOST_BOOT;
+}
+
+static int host_line_ieq(const char *line, const char *prefix)
+{
+    size_t i;
+    size_t plen = strlen(prefix);
+
+    for (i = 0; i < plen; i++) {
+        char a = (char)tolower((unsigned char)line[i]);
+        char b = (char)tolower((unsigned char)prefix[i]);
+
+        if (a != b) {
+            return 0;
+        }
+    }
+
+    return 1;
+}
+
+static void host_emit_event(hybbx_tnc_host_t *host, hybbx_tnc_host_state_t state)
+{
+    if (host->state == state) {
+        return;
+    }
+
+    host->state = state;
+    if (host->event_cb != NULL) {
+        host->event_cb(state, host->userdata);
+    }
+}
+
+static void host_process_line(hybbx_tnc_host_t *host)
+{
+    const char *line = host->line;
+
+    if (host_line_ieq(line, "cmd:") || host_line_ieq(line, "cmd: ")) {
+        host_emit_event(host, HYBBX_TNC_HOST_CMD);
+        return;
+    }
+
+    if (strstr(line, "***") != NULL &&
+        (host_line_ieq(line, "*** connected") ||
+         host_line_ieq(line, "*** connected ") ||
+         strstr(line, "CONNECTED") != NULL)) {
+        host_emit_event(host, HYBBX_TNC_HOST_CONNECTED);
+        return;
+    }
+
+    if (strstr(line, "***") != NULL &&
+        (host_line_ieq(line, "*** disconnected") ||
+         strstr(line, "DISCONNECTED") != NULL)) {
+        host_emit_event(host, HYBBX_TNC_HOST_CMD);
+        return;
+    }
+
+    if (host->state == HYBBX_TNC_HOST_CONNECTED && host->text_cb != NULL &&
+        line[0] != '\0') {
+        host->text_cb((const uint8_t *)line, strlen(line), host->userdata);
+        host->text_cb((const uint8_t *)"\r\n", 2, host->userdata);
+    }
+}
+
+static void host_push_byte(hybbx_tnc_host_t *host, uint8_t byte)
+{
+    if (byte == '\r' || byte == '\n') {
+        if (host->line_len > 0) {
+            host->line[host->line_len] = '\0';
+            host_process_line(host);
+            host->line_len = 0;
+        }
+        return;
+    }
+
+    if (host->line_len + 1 >= sizeof(host->line)) {
+        host->line_len = 0;
+        return;
+    }
+
+    host->line[host->line_len++] = (char)byte;
+}
+
+void hybbx_tnc_host_feed(hybbx_tnc_host_t *host,
+                         const uint8_t *data, size_t len)
+{
+    size_t i;
+
+    if (host == NULL || data == NULL) {
+        return;
+    }
+
+    for (i = 0; i < len; i++) {
+        host_push_byte(host, data[i]);
+    }
+}
+
+size_t hybbx_tnc_host_format_cmd(const char *cmd, char *out, size_t out_cap)
+{
+    size_t len;
+
+    if (cmd == NULL || out == NULL || out_cap < 3) {
+        return 0;
+    }
+
+    len = strlen(cmd);
+    if (len + 2 >= out_cap) {
+        return 0;
+    }
+
+    memcpy(out, cmd, len);
+    out[len++] = '\r';
+    out[len] = '\0';
+    return len;
+}