code: сохранение данных из сети в буфер

main.cpp

@@ -1,3 +1,5 @@
+#include <sstream>
+#include <string>
 #include <iostream>
 #include <cmath>
 #include <vector>
@@ -17,6 +19,17 @@ struct Input
     size_t bin_count{};
 };
 
+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
 input_data(istream& in, bool prompt)
 {
@@ -28,7 +41,7 @@ input_data(istream& in, bool prompt)
     Input rez;
 
     if(prompt)
-        cerr << "bin_count= ";
+        cerr << "numbers= ";
     rez.numbers.resize(number_count);
 
     for (size_t i = 0; i < number_count; i++)
@@ -41,32 +54,39 @@ input_data(istream& in, bool prompt)
     return rez;
 }
 
+Input
+download(const string& address) {
+    stringstream buffer;
 
-int main(int argc, char* argv[])
-{
-    if (argc > 1)
-    {
     CURL* curl = curl_easy_init();
     if(curl)
     {
         CURLcode res;
-        curl_easy_setopt(curl, CURLOPT_URL, argv[1]);
+        curl_easy_setopt(curl, CURLOPT_URL, address.c_str());
         res = curl_easy_perform(curl);
         if (res != 0)
             {
             cout << curl_easy_strerror(res);
             exit(1);
             }
+        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, &buffer);
+
         curl_easy_cleanup(curl);
     }
-        return 0;
-    }
+    return input_data(buffer, false);
+}
 
-    curl_global_init(CURL_GLOBAL_ALL);
 
-    bool prompt = true;
-    auto in = input_data(cin, prompt);
-    auto bins = make_histogram(in.numbers, in.bin_count);
+int main(int argc, char* argv[])
+{
+    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);
     return 0;
 }