Add solution to ex04 (without Makefile)

diff --git a/ex04/main.cpp b/ex04/main.cpp
new file mode 100644 (file)
index 0000000..696626c
--- /dev/null
+++ b/ex04/main.cpp
@@ -0,0 +1,67 @@
+#include <string>
+#include <fstream>
+#include <iostream>
+
+int    open_files(const char *filename, std::ifstream &old_file, std::ofstream &new_file)
+{
+       old_file.open(filename);
+       if (!old_file)
+       {
+               std::cout << "File " << filename << " not found!\n";
+               return (1);
+       }
+       new_file.open(std::string(filename).append(".replace").c_str());
+       if (!new_file)
+       {
+               std::cout << "File " << filename << ".replace could not be created!\n";
+               old_file.close();
+               return (1);
+       }
+       return (0);
+}
+
+void   rewrite_file(std::ifstream &old_file, std::ofstream &new_file,
+                       std::string old_string, std::string new_string)
+{
+       std::string     line;
+       size_t          i;
+       size_t          j;
+
+       while (!old_file.eof())
+       {
+               std::getline(old_file, line);
+               j = 0;
+               while (1)
+               {
+                       i = line.find(old_string, j);
+                       if (i == std::string::npos)
+                               break ;
+                       new_file << line.substr(j, i - j) << new_string;
+                       j = i + old_string.size();
+               }
+               new_file << line.substr(j) << '\n';
+       }
+}
+
+int    main(int argc, char **argv)
+{
+       std::ifstream   old_file;
+       std::ofstream   new_file;
+       std::string             old_str;
+       std::string             new_str;
+
+       if (argc != 4)
+       {
+               std::cout << "Wrong argument number, the correct usage is:\n"
+                       "\tex04 FILENAME OLD_STRING NEW_STRING\n";
+               return (1);
+       }
+       if (open_files(argv[1], old_file, new_file))
+               return (2);
+       old_str = argv[2];
+       new_str = argv[3];
+       rewrite_file(old_file, new_file, old_str, new_str);
+       old_file.close();
+       new_file.close();
+}
+