feat: add /info endpoint for getting information about an instance

src/Main.c

@@ -12,6 +12,7 @@
 #include "Routes/Home.h"
 #include "Routes/ImageProxy.h"
 #include "Routes/Images.h"
+#include "Routes/Info.h"
 #include "Routes/Search.h"
 #include "Routes/Settings.h"
 #include "Routes/SettingsSave.h"
@@ -138,6 +139,7 @@ int main() {
   set_handler("/search", results_handler);
   set_handler("/images", images_handler);
   set_handler("/proxy", image_proxy_handler);
+  set_handler("/info", info_handler);
   set_handler("/settings", settings_handler);
   set_handler("/save_settings", settings_save_handler);
 

src/Routes/Info.c

@@ -0,0 +1,69 @@
+#include "Info.h"
+#include "../Config.h"
+#include "../Scraping/Scraping.h"
+#include "../Utility/Utility.h"
+#include <beaker.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+static int append_json(char *buf, size_t size, size_t *used, const char *format,
+                       ...) {
+  if (*used >= size) {
+    return -1;
+  }
+
+  va_list args;
+  va_start(args, format);
+  int written = vsnprintf(buf + *used, size - *used, format, args);
+  va_end(args);
+
+  if (written < 0 || (size_t)written >= size - *used) {
+    return -1;
+  }
+
+  *used += (size_t)written;
+  return 0;
+}
+
+int info_handler(UrlParams *params) {
+  (void)params;
+  extern Config global_config;
+
+  char json[INITIAL_BUFFER_SIZE];
+  size_t used = 0;
+
+  if (append_json(json, sizeof(json), &used, "{\"version\":\"%s\",", VERSION) !=
+          0 ||
+      append_json(json, sizeof(json), &used, "\"git_remote\":\"%s\",",
+                  GIT_REMOTE) != 0 ||
+      append_json(json, sizeof(json), &used, "\"locale\":\"%s\",",
+                  global_config.default_locale) != 0 ||
+      append_json(json, sizeof(json), &used, "\"engines\":[") != 0) {
+    send_response("Failed to build instance info");
+    return -1;
+  }
+
+  int first = 1;
+  for (int i = 0; i < ENGINE_COUNT; i++) {
+    if (!ENGINE_REGISTRY[i].enabled) {
+      continue;
+    }
+    if (append_json(json, sizeof(json), &used,
+                    "%s{\"id\":\"%s\",\"name\":\"%s\"}", first ? "" : ",",
+                    ENGINE_REGISTRY[i].id, ENGINE_REGISTRY[i].name) != 0) {
+      send_response("Failed to build instance info");
+      return -1;
+    }
+    first = 0;
+  }
+
+  if (append_json(json, sizeof(json), &used, "]}") != 0) {
+    send_response("Failed to build instance info");
+    return -1;
+  }
+
+  serve_data(json, used, "application/json");
+
+  return 0;
+}

src/Routes/Info.h

@@ -0,0 +1,8 @@
+#ifndef INFO_H
+#define INFO_H
+
+#include <beaker.h>
+
+int info_handler(UrlParams *params);
+
+#endif