code: реализована загрузка файлов по сети, сохранение данных в буфер и обработка ошибок

main.cpp

@@ -1,65 +1,95 @@
 #include <iostream>
 #include <vector>
-#include <curl/curl.h>
 #include "histogram.h"
 #include "text.h"
 #include "svg.h"
+#include <curl/curl.h>
+#include <sstream>
+#include <string>
 
 using namespace std;
 
 struct Input {
-    vector<double> dn;
     vector<double> numbers;
     size_t bin_count{};
-    size_t number_count{};
-    size_t max_count{};
 };
 
-Input
-input_data(istream& cin, bool prompt) {
-    if (prompt == true){
-    Input in;
-    cerr << "Enter number count: ";
-    cin >> in.number_count;
-    vector<double> numbers(in.number_count);
-    in.numbers.resize(in.number_count);
-    for (size_t i = 0; i < in.number_count; i++) {
-        cin >> in.numbers[i];
-    }
-    size_t bin_count;
-    cerr << "Enter bin count: ";
-    cin >> in.bin_count;
+Input input_data(istream& stream, bool prompt) {
 
-    size_t max_count;
-    in.max_count = 0;
-    return in;
+
+    size_t number_count;
+    if (prompt) {
+        cerr << "Enter number count: ";
     }
-    else{
+    stream >> number_count;
+
     Input in;
-    cin >> in.number_count;
-    vector<double> numbers(in.number_count);
-    in.numbers.resize(in.number_count);
-    for (size_t i = 0; i < in.number_count; i++) {
-        cin >> in.numbers[i];
+
+    in.numbers.resize(number_count);
+
+    if (prompt){
+            cerr << "Enter numbers: ";
+    }
+    for (size_t i = 0; i < number_count; i++)
+    {
+        stream >> in.numbers[i];
     }
-    size_t bin_count;
-    cin >> in.bin_count;
 
-    size_t max_count;
-    in.max_count = 0;
-    return in;
+    if (prompt){
+    cerr << "Enter number of bins: ";
     }
+        stream >> in.bin_count;
+
+    return in;
+}
+
+size_t write_data(void* items, size_t item_size, size_t item_count, void* ctx) { // ðàçìåð ïðèíÿòûõ äàííûõ â áàéòàõ, èíà÷å curl_easy_perform() îñòàíîâèò ðàáîòó ñ îøèáêîé.
+    size_t data_size = item_size * item_count;
+    stringstream* buffer = reinterpret_cast<stringstream*>(ctx); // stringstream — ïîòîê, êîòîðûé ìîæåò ÷èòàòü èç áóôåðà â ïàìÿòè.
+    auto text = reinterpret_cast<const char*>(items);
+    buffer->write(text, data_size);
+    return data_size;
 }
 
 
+Input download(const string& address) {
 
-int main(){
+    stringstream buffer;
 
     curl_global_init(CURL_GLOBAL_ALL);
 
-    bool res = false;
+        CURL* curl = curl_easy_init(); // CURL* - äåñêðèïòîð, ñëîæíûé îáúåêò, ïåðåäàâàòü èõ ôóíêöèÿì áèáëèîòåêè è ñðàâíèâàòü ìåæäó ñîáîé
+
+        if(curl) {
+
+            CURLcode res;
+            curl_easy_setopt(curl, CURLOPT_URL, address.c_str());
+            curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data); // áèáëèîòåêà ìîæåò âûçûâàòü ôóíêöèþ, êîòîðóþ óêàæåò ïðîãðàììà.
+            curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
+            res = curl_easy_perform(curl);
+
+            if (res != CURLE_OK) {
+                curl_easy_strerror(res);
+                exit(1);
+            }
+            cerr << res << endl;
+            curl_easy_cleanup(curl);
+        }
+    return input_data(buffer, false);
+}
+
+
+
+
+int main(int argc, char* argv[]){
+
+    Input in;
+    if (argc > 1) {
+        in = download(argv[1]);
+    } else {
+        in = input_data(cin, true);
+    }
 
-    auto in = input_data(cin, true);
 
     auto bins = make_histogram(in.numbers, in.bin_count);