hscript: Add download_file helper and implement SigningKey::execute0.1.0

1 files changed, 61 insertions, 0 deletions

diff --git a/hscript/util.cc b/hscript/util.cc
new file mode 100644
index 0000000..4a991c5
--- /dev/null
+++ b/hscript/util.cc
@@ -0,0 +1,61 @@
+/*
+ * util.cc - Implementation of useful utility routines
+ * libhscript, the HorizonScript library for
+ * Project Horizon
+ *
+ * Copyright (c) 2019 Adélie Linux and contributors.  All rights reserved.
+ * This code is licensed under the AGPL 3.0 license, as noted in the
+ * LICENSE-code file in the root directory of this repository.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+#include <string>
+#ifdef HAVE_LIBCURL
+#    include <cstdio>       /* fopen */
+#    include <cstring>      /* strerror */
+#    include <curl/curl.h>  /* curl_* */
+#    include <errno.h>      /* errno */
+#endif /* HAVE_LIBCURL */
+#include "util/output.hh"
+
+#ifdef HAVE_LIBCURL
+bool download_file(const std::string &url, const std::string &path) {
+    CURL *curl = curl_easy_init();
+    CURLcode result;
+    bool return_code = false;
+    char errbuf[CURL_ERROR_SIZE];
+    FILE *fp;
+
+    if(curl == nullptr) {
+        output_error("internal", "trouble initialising cURL library");
+        return false;
+    }
+
+    fp = fopen(path.c_str(), "w");
+    if(fp == nullptr) {
+        output_error("internal", "couldn't open " + path + " for writing",
+                     strerror(errno));
+        curl_easy_cleanup(curl);
+        return false;
+    }
+
+    curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
+    curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errbuf);
+    curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
+
+    result = curl_easy_perform(curl);
+    if(result == CURLE_OK) {
+        return_code = true;
+    } else {
+        output_error("curl", "couldn't download file", errbuf);
+    }
+    curl_easy_cleanup(curl);
+    return return_code;
+}
+#else /* !HAVE_LIBCURL */
+bool download_file(const std::string &url, const std::string &path) {
+    output_error("internal", "can't download without linking to cURL");
+    return false;
+}
+#endif /* HAVE_LIBCURL */