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1 files changed, 104 insertions, 0 deletions

diff --git a/src/download.c b/src/download.c
new file mode 100644
index 0000000..211987a
--- /dev/null
+++ b/src/download.c
@@ -0,0 +1,104 @@
+/*
+ * download.c
+ * file download helper functions
+ *
+ * Copyright (c) 2012 Nikias Bassen. All Rights Reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <curl/curl.h>
+
+#include "download.h"
+
+typedef struct {
+	int length;
+	char* content;
+} curl_response;
+
+static size_t download_write_buffer_callback(char* data, size_t size, size_t nmemb, curl_response* response) {
+	size_t total = size * nmemb;
+	if (total != 0) {
+		response->content = realloc(response->content, response->length + total + 1);
+		memcpy(response->content + response->length, data, total);
+		response->content[response->length + total] = '\0';
+		response->length += total;
+	}
+	return total;
+}
+
+int download_to_buffer(const char* url, char** buf, uint32_t* length)
+{
+	curl_global_init(CURL_GLOBAL_ALL);
+	CURL* handle = curl_easy_init();
+	if (handle == NULL) {
+		error("ERROR: could not initialize CURL\n");
+		return -1;
+	}
+
+	curl_response response;
+	response.length = 0;
+	response.content = malloc(1);
+	response.content[0] = '\0';
+
+	curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, (curl_write_callback)&download_write_buffer_callback);
+	curl_easy_setopt(handle, CURLOPT_WRITEDATA, &response);
+	curl_easy_setopt(handle, CURLOPT_USERAGENT, "InetURL/1.0");
+	curl_easy_setopt(handle, CURLOPT_URL, url);
+
+	curl_easy_perform(handle);
+	curl_easy_cleanup(handle);
+
+	if (response.content) {
+		*length = response.length;
+		*buf = response.content;
+	}
+
+	curl_global_cleanup();
+
+	return 0;
+}
+
+int download_to_file(const char* url, const char* filename)
+{
+	curl_global_init(CURL_GLOBAL_ALL);
+	CURL* handle = curl_easy_init();
+	if (handle == NULL) {
+		error("ERROR: could not initialize CURL\n");
+		return -1;
+	}
+
+	FILE* f = fopen(filename, "wb");
+	if (!f) {
+		error("ERROR: cannot open '%s' for writing\n", filename);
+		return -1;
+	}
+
+	curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, (curl_write_callback)&fwrite);
+	curl_easy_setopt(handle, CURLOPT_WRITEDATA, f);
+	curl_easy_setopt(handle, CURLOPT_USERAGENT, "InetURL/1.0");
+	curl_easy_setopt(handle, CURLOPT_URL, url);
+
+	curl_easy_perform(handle);
+	curl_easy_cleanup(handle);
+
+	fclose(f);
+
+	curl_global_cleanup();
+
+	return 0;
+}