Merge pull request #193 from lukash/replace-fstream

Use C-style IO instead of ifstream for parsing

tests/test_parse_file.cpp

@@ -142,6 +142,75 @@ BOOST_AUTO_TEST_CASE(test_example_stream)
     }
 }
 
+BOOST_AUTO_TEST_CASE(test_example_file_pointer)
+{
+    FILE * file = fopen("toml/tests/example.toml", "rb");
+    const auto data = toml::parse(file, "toml/tests/example.toml");
+    fclose(file);
+
+    BOOST_TEST(toml::find<std::string>(data, "title") == "TOML Example");
+    const auto& owner = toml::find(data, "owner");
+    {
+        BOOST_TEST(toml::find<std::string>(owner, "name") == "Tom Preston-Werner");
+        BOOST_TEST(toml::find<std::string>(owner, "organization") == "GitHub");
+        BOOST_TEST(toml::find<std::string>(owner, "bio") ==
+                          "GitHub Cofounder & CEO\nLikes tater tots and beer.");
+        BOOST_TEST(toml::find<toml::offset_datetime>(owner, "dob") ==
+                          toml::offset_datetime(toml::local_date(1979, toml::month_t::May, 27),
+                                                toml::local_time(7, 32, 0), toml::time_offset(0, 0)));
+    }
+
+    const auto& database = toml::find(data, "database");
+    {
+        BOOST_TEST(toml::find<std::string>(database, "server") == "192.168.1.1");
+        const std::vector<int> expected_ports{8001, 8001, 8002};
+        BOOST_CHECK(toml::find<std::vector<int>>(database, "ports") == expected_ports);
+        BOOST_TEST(toml::find<int >(database, "connection_max") == 5000);
+        BOOST_TEST(toml::find<bool>(database, "enabled") == true);
+    }
+
+    const auto& servers = toml::find(data, "servers");
+    {
+        toml::table alpha = toml::find<toml::table>(servers, "alpha");
+        BOOST_TEST(toml::get<std::string>(alpha.at("ip")) == "10.0.0.1");
+        BOOST_TEST(toml::get<std::string>(alpha.at("dc")) == "eqdc10");
+
+        toml::table beta = toml::find<toml::table>(servers, "beta");
+        BOOST_TEST(toml::get<std::string>(beta.at("ip")) == "10.0.0.2");
+        BOOST_TEST(toml::get<std::string>(beta.at("dc")) == "eqdc10");
+        BOOST_TEST(toml::get<std::string>(beta.at("country")) == "\xE4\xB8\xAD\xE5\x9B\xBD");
+    }
+
+    const auto& clients = toml::find(data, "clients");
+    {
+        toml::array clients_data = toml::find<toml::array>(clients, "data");
+        std::vector<std::string> expected_name{"gamma", "delta"};
+        BOOST_CHECK(toml::get<std::vector<std::string>>(clients_data.at(0)) == expected_name);
+
+        std::vector<int> expected_number{1, 2};
+        BOOST_CHECK(toml::get<std::vector<int>>(clients_data.at(1)) == expected_number);
+
+        std::vector<std::string> expected_hosts{"alpha", "omega"};
+        BOOST_CHECK(toml::find<std::vector<std::string>>(clients, "hosts") == expected_hosts);
+    }
+
+    std::vector<toml::table> products =
+        toml::find<std::vector<toml::table>>(data, "products");
+    {
+        BOOST_TEST(toml::get<std::string>(products.at(0).at("name")) ==
+                          "Hammer");
+        BOOST_TEST(toml::get<std::int64_t>(products.at(0).at("sku")) ==
+                          738594937);
+
+        BOOST_TEST(toml::get<std::string>(products.at(1).at("name")) ==
+                          "Nail");
+        BOOST_TEST(toml::get<std::int64_t>(products.at(1).at("sku")) ==
+                          284758393);
+        BOOST_TEST(toml::get<std::string>(products.at(1).at("color")) ==
+                          "gray");
+    }
+}
+
 BOOST_AUTO_TEST_CASE(test_fruit)
 {
     const auto data = toml::parse("toml/tests/fruit.toml");
@@ -959,3 +1028,8 @@ BOOST_AUTO_TEST_CASE(test_parse_function_compiles)
     BOOST_TEST_MESSAGE("path");
 #endif
 }
+
+BOOST_AUTO_TEST_CASE(test_parse_nonexistent_file)
+{
+    BOOST_CHECK_THROW(toml::parse("nonexistent.toml"), std::ios_base::failure);
+}

toml/exception.hpp

@@ -10,6 +10,18 @@
 namespace toml
 {
 
+struct file_io_error : public std::runtime_error
+{
+  public:
+    file_io_error(int errnum, const std::string& msg, const std::string& fname)
+        : std::runtime_error(msg + " \"" + fname + "\": " + std::strerror(errnum)),
+          errno_(errnum)
+    {}
+    int get_errno() {return errno_;}
+  private:
+    int errno_;
+};
+
 struct exception : public std::exception
 {
   public:

toml/lexer.hpp

@@ -5,7 +5,6 @@
 #include <istream>
 #include <sstream>
 #include <stdexcept>
-#include <fstream>
 
 #include "combinator.hpp"
 

toml/parser.hpp

@@ -2377,27 +2377,14 @@ result<Value, std::string> parse_toml_file(location& loc)
     return ok(Value(std::move(data), file, comments));
 }
 
-} // detail
-
 template<typename                     Comment = TOML11_DEFAULT_COMMENT_STRATEGY,
          template<typename ...> class Table   = std::unordered_map,
          template<typename ...> class Array   = std::vector>
 basic_value<Comment, Table, Array>
-parse(std::istream& is, std::string fname = "unknown file")
+parse(std::vector<char>& letters, const std::string& fname)
 {
     using value_type = basic_value<Comment, Table, Array>;
 
-    const auto beg = is.tellg();
-    is.seekg(0, std::ios::end);
-    const auto end = is.tellg();
-    const auto fsize = end - beg;
-    is.seekg(beg);
-
-    // read whole file as a sequence of char
-    assert(fsize >= 0);
-    std::vector<char> letters(static_cast<std::size_t>(fsize));
-    is.read(letters.data(), fsize);
-
     // append LF.
     // Although TOML does not require LF at the EOF, to make parsing logic
     // simpler, we "normalize" the content by adding LF if it does not exist.
@@ -2435,16 +2422,75 @@ parse(std::istream& is, std::string fname = "unknown file")
     return data.unwrap();
 }
 
+} // detail
+
+template<typename                     Comment = TOML11_DEFAULT_COMMENT_STRATEGY,
+         template<typename ...> class Table   = std::unordered_map,
+         template<typename ...> class Array   = std::vector>
+basic_value<Comment, Table, Array>
+parse(FILE * file, const std::string& fname)
+{
+    const long beg = std::ftell(file);
+    if (beg == -1l) {
+        throw file_io_error(errno, "Failed to access", fname);
+    }
+
+    int res = std::fseek(file, 0, SEEK_END);
+    if (res != 0) {
+        throw file_io_error(errno, "Failed to seek", fname);
+    }
+
+    const long end = std::ftell(file);
+    if (end == -1l) {
+        throw file_io_error(errno, "Failed to access", fname);
+    }
+
+    const auto fsize = end - beg;
+
+    res = std::fseek(file, beg, SEEK_SET);
+    if (res != 0) {
+        throw file_io_error(errno, "Failed to seek", fname);
+    }
+
+    // read whole file as a sequence of char
+    assert(fsize >= 0);
+    std::vector<char> letters(static_cast<std::size_t>(fsize));
+    std::fread(letters.data(), sizeof(char), static_cast<std::size_t>(fsize), file);
+
+    return detail::parse<Comment, Table, Array>(letters, fname);
+}
+
+template<typename                     Comment = TOML11_DEFAULT_COMMENT_STRATEGY,
+         template<typename ...> class Table   = std::unordered_map,
+         template<typename ...> class Array   = std::vector>
+basic_value<Comment, Table, Array>
+parse(std::istream& is, std::string fname = "unknown file")
+{
+    const auto beg = is.tellg();
+    is.seekg(0, std::ios::end);
+    const auto end = is.tellg();
+    const auto fsize = end - beg;
+    is.seekg(beg);
+
+    // read whole file as a sequence of char
+    assert(fsize >= 0);
+    std::vector<char> letters(static_cast<std::size_t>(fsize));
+    is.read(letters.data(), fsize);
+
+    return detail::parse<Comment, Table, Array>(letters, fname);
+}
+
 template<typename                     Comment = TOML11_DEFAULT_COMMENT_STRATEGY,
          template<typename ...> class Table   = std::unordered_map,
          template<typename ...> class Array   = std::vector>
 basic_value<Comment, Table, Array> parse(std::string fname)
 {
-    std::ifstream ifs(fname.c_str(), std::ios_base::binary);
+    std::ifstream ifs(fname, std::ios_base::binary);
     if(!ifs.good())
     {
-        throw std::runtime_error("toml::parse: file open error -> " + fname);
+        throw std::ios_base::failure("toml::parse: Error opening file \"" + fname + "\"");
     }
+    ifs.exceptions(std::ifstream::failbit | std::ifstream::badbit);
     return parse<Comment, Table, Array>(ifs, std::move(fname));
 }
 
@@ -2471,13 +2517,7 @@ template<typename                     Comment = TOML11_DEFAULT_COMMENT_STRATEGY,
          template<typename ...> class Array   = std::vector>
 basic_value<Comment, Table, Array> parse(const std::filesystem::path& fpath)
 {
-    std::ifstream ifs(fpath, std::ios_base::binary);
+    return parse<Comment, Table, Array>(fpath.string());
-    if(!ifs.good())
-    {
-        throw std::runtime_error("toml::parse: file open error -> " +
-                                 fpath.string());
-    }
-    return parse<Comment, Table, Array>(ifs, fpath.string());
 }
 #endif // TOML11_HAS_STD_FILESYSTEM