code: Сохранение данных из сети в буфер

.gitignore

@@ -3,3 +3,4 @@
 /*.layout
 /*.depend
 /*.o
+/curl

main.cpp

@@ -1,5 +1,8 @@
 #include <iostream>
 #include <vector>
+#include <sstream>
+#include <string>
+#include <curl/curl.h>
 #include "histogram.h"
 #include "text.h"
 #include "svg.h"
@@ -34,9 +37,41 @@ Input input_data(istream& stream, bool prompt) {
   return in;
 }
 
-int main()
+size_t
+write_data(void* items, size_t item_size, size_t item_count, void* ctx) {
+    size_t data_size = item_size * item_count;
+    stringstream* buffer = reinterpret_cast<stringstream*>(ctx);
+    (*buffer).write(reinterpret_cast<const char*>(items), data_size);
+    return data_size;
+}
+
+Input
+download(const string& address) {
+    stringstream buffer;
+    CURL *curl = curl_easy_init();
+    if(curl) {
+        CURLcode res;
+        curl_easy_setopt(curl, CURLOPT_URL, address.c_str());
+        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
+        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
+        res = curl_easy_perform(curl);
+        if (res!=CURLE_OK){
+            cerr << curl_easy_strerror(res);
+            exit(1);
+        }
+        curl_easy_cleanup(curl);
+    }
+    return input_data(buffer, false);
+}
+
+int main(int argc, char* argv[])
 {
-    Input in = input_data(cin, false);
-    vector<size_t> bins = make_histogram(in.numbers, in.bin_count);
+    Input input;
+    if (argc > 1) {
+        input = download(argv[1]);
+    } else {
+        input = input_data(cin, true);
+    }
+    const auto bins = make_histogram(input.numbers, input.bin_count);
     show_histogram_svg(bins);
 }