介绍
一般的ini配置文件由节、键、值组成。
【参数】（键=值），例如 :key=value;
【节】：所有的参数都是以节（section）为单位结合在一起的。所有的section名称都是独占一行，并且section名字都被方括号包围着（[XXX]）。在section声明后的所有parameters都属于该section。
例如：[section1]
所以一个包含节，键，值的简单ini配置文件，例如：
[port]
portName=port1
port=123
1.使用INIReader.h头文件
1.INIReader.h
// Read an INI file into easy-to-access name/value pairs.
// inih and INIReader are released under the New BSD license (see LICENSE.txt).
// Go to the project home page for more info:
//
// https://github.com/benhoyt/inih
#ifndef __INI_H__
#define __INI_H__
#ifdef __cplusplus
extern "C" {
#endif
#include <stdio.h>
typedef int (*ini_handler)(void* user, const char* section,
const char* name, const char* value);
typedef char* (*ini_reader)(char* str, int num, void* stream);
int ini_parse(const char* filename, ini_handler handler, void* user);
int ini_parse_file(FILE* file, ini_handler handler, void* user);
int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,
void* user);
#ifndef INI_ALLOW_MULTILINE
#define INI_ALLOW_MULTILINE 1
#endif
#ifndef INI_ALLOW_BOM
#define INI_ALLOW_BOM 1
#endif
#ifndef INI_ALLOW_INLINE_COMMENTS
#define INI_ALLOW_INLINE_COMMENTS 1
#endif
#ifndef INI_INLINE_COMMENT_PREFIXES
#define INI_INLINE_COMMENT_PREFIXES ";"
#endif
#ifndef INI_USE_STACK
#define INI_USE_STACK 1
#endif
#ifndef INI_STOP_ON_FIRST_ERROR
#define INI_STOP_ON_FIRST_ERROR 0
#endif
#ifndef INI_MAX_LINE
#define INI_MAX_LINE 200
#endif
#ifdef __cplusplus
}
#endif
#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
#define _CRT_SECURE_NO_WARNINGS
#endif
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#if !INI_USE_STACK
#include <stdlib.h>
#endif
#define MAX_SECTION 50
#define MAX_NAME 50
inline static char* rstrip(char* s)
{
char* p = s + strlen(s);
while (p > s && isspace((unsigned char)(*--p)))
*p = '\0';
return s;
}
inline static char* lskip(const char* s)
{
while (*s && isspace((unsigned char)(*s)))
s++;
return (char*)s;
}
inline static char* find_chars_or_comment(const char* s, const char* chars)
{
#if INI_ALLOW_INLINE_COMMENTS
int was_space = 0;
while (*s && (!chars || !strchr(chars, *s)) &&
!(was_space && strchr(INI_INLINE_COMMENT_PREFIXES, *s))) {
was_space = isspace((unsigned char)(*s));
s++;
}
#else
while (*s && (!chars || !strchr(chars, *s))) {
s++;
}
#endif
return (char*)s;
}
inline static char* strncpy0(char* dest, const char* src, size_t size)
{
strncpy(dest, src, size);
dest[size - 1] = '\0';
return dest;
}
inline int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,
void* user)
{
#if INI_USE_STACK
char line[INI_MAX_LINE];
#else
char* line;
#endif
char section[MAX_SECTION] = "";
char prev_name[MAX_NAME] = "";
char* start;
char* end;
char* name;
char* value;
int lineno = 0;
int error = 0;
#if !INI_USE_STACK
line = (char*)malloc(INI_MAX_LINE);
if (!line) {
return -2;
}
#endif
while (reader(line, INI_MAX_LINE, stream) != NULL) {
lineno++;
start = line;
#if INI_ALLOW_BOM
if (lineno == 1 && (unsigned char)start[0] == 0xEF &&
(unsigned char)start[1] == 0xBB &&
(unsigned char)start[2] == 0xBF) {
start += 3;
}
#endif
start = lskip(rstrip(start));
if (*start == ';' || *start == '#') {
}
#if INI_ALLOW_MULTILINE
else if (*prev_name && *start && start > line) {
#if INI_ALLOW_INLINE_COMMENTS
end = find_chars_or_comment(start, NULL);
if (*end)
*end = '\0';
rstrip(start);
#endif
if (!handler(user, section, prev_name, start) && !error)
error = lineno;
}
#endif
else if (*start == '[') {
end = find_chars_or_comment(start + 1, "]");
if (*end == ']') {
*end = '\0';
strncpy0(section, start + 1, sizeof(section));
*prev_name = '\0';
}
else if (!error) {
error = lineno;
}
}
else if (*start) {
end = find_chars_or_comment(start, "=:");
if (*end == '=' || *end == ':') {
*end = '\0';
name = rstrip(start);
value = lskip(end + 1);
#if INI_ALLOW_INLINE_COMMENTS
end = find_chars_or_comment(value, NULL);
if (*end)
*end = '\0';
#endif
rstrip(value);
strncpy0(prev_name, name, sizeof(prev_name));
if (!handler(user, section, name, value) && !error)
error = lineno;
}
else if (!error) {
error = lineno;
}
}
#if INI_STOP_ON_FIRST_ERROR
if (error)
break;
#endif
}
#if !INI_USE_STACK
free(line);
#endif
return error;
}
inline int ini_parse_file(FILE* file, ini_handler handler, void* user)
{
return ini_parse_stream((ini_reader)fgets, file, handler, user);
}
inline int ini_parse(const char* filename, ini_handler handler, void* user)
{
FILE* file;
int error;
file = fopen(filename, "r");
if (!file)
return -1;
error = ini_parse_file(file, handler, user);
fclose(file);
return error;
}
#endif
#ifndef __INIREADER_H__
#define __INIREADER_H__
#include <map>
#include <set>
#include <string>
// Read an INI file into easy-to-access name/value pairs. (Note that I've gone
// for simplicity here rather than speed, but it should be pretty decent.)
class INIReader
{
public:
// Empty Constructor
INIReader() {};
// Construct INIReader and parse given filename. See ini.h for more info
// about the parsing.
explicit INIReader(const std::string& filename);
// Construct INIReader and parse given file. See ini.h for more info
// about the parsing.
explicit INIReader(FILE *file);
// Return the result of ini_parse(), i.e., 0 on success, line number of
// first error on parse error, or -1 on file open error.
int ParseError() const;
// Return the list of sections found in ini file
const std::set<std::string>& Sections() const;
// Get a string value from INI file, returning default_value if not found.
std::string Get(const std::string& section, const std::string& name,
const std::string& default_value) const;
// Get an integer (long) value from INI file, returning default_value if
// not found or not a valid integer (decimal "1234", "-1234", or hex "0x4d2").
long GetInteger(const std::string& section, const std::string& name, long default_value) const;
// Get a real (floating point double) value from INI file, returning
// default_value if not found or not a valid floating point value
// according to strtod().
double GetReal(const std::string& section, const std::string& name, double default_value) const;
// Get a single precision floating point number value from INI file, returning
// default_value if not found or not a valid floating point value
// according to strtof().
float GetFloat(const std::string& section, const std::string& name, float default_value) const;
// Get a boolean value from INI file, returning default_value if not found or if
// not a valid true/false value. Valid true values are "true", "yes", "on", "1",
// and valid false values are "false", "no", "off", "0" (not case sensitive).
bool GetBoolean(const std::string& section, const std::string& name, bool default_value) const;
protected:
int _error;
std::map<std::string, std::string> _values;
std::set<std::string> _sections;
static std::string MakeKey(const std::string& section, const std::string& name);
static int ValueHandler(void* user, const char* section, const char* name,
const char* value);
};
#endif // __INIREADER_H__
#ifndef __INIREADER__
#define __INIREADER__
#include <algorithm>
#include <cctype>
#include <cstdlib>
inline INIReader::INIReader(const std::string& filename)
{
_error = ini_parse(filename.c_str(), ValueHandler, this);
}
inline INIReader::INIReader(FILE *file)
{
_error = ini_parse_file(file, ValueHandler, this);
}
inline int INIReader::ParseError() const
{
return _error;
}
inline const std::set<std::string>& INIReader::Sections() const
{
return _sections;
}
inline std::string INIReader::Get(const std::string& section, const std::string& name, const std::string& default_value) const
{
std::string key = MakeKey(section, name);
return _values.count(key) ? _values.at(key) : default_value;
}
inline long INIReader::GetInteger(const std::string& section, const std::string& name, long default_value) const
{
std::string valstr = Get(section, name, "");
const char* value = valstr.c_str();
char* end;
// This parses "1234" (decimal) and also "0x4D2" (hex)
long n = strtol(value, &end, 0);
return end > value ? n : default_value;
}
inline double INIReader::GetReal(const std::string& section, const std::string& name, double default_value) const
{
std::string valstr = Get(section, name, "");
const char* value = valstr.c_str();
char* end;
double n = strtod(value, &end);
return end > value ? n : default_value;
}
inline float INIReader::GetFloat(const std::string& section, const std::string& name, float default_value) const
{
std::string valstr = Get(section, name, "");
const char* value = valstr.c_str();
char* end;
float n = strtof(value, &end);
return end > value ? n : default_value;
}
inline bool INIReader::GetBoolean(const std::string& section, const std::string& name, bool default_value) const
{
std::string valstr = Get(section, name, "");
// Convert to lower case to make string comparisons case-insensitive
std::transform(valstr.begin(), valstr.end(), valstr.begin(), ::tolower);
if (valstr == "true" || valstr == "yes" || valstr == "on" || valstr == "1")
return true;
else if (valstr == "false" || valstr == "no" || valstr == "off" || valstr == "0")
return false;
else
return default_value;
}
inline std::string INIReader::MakeKey(const std::string& section, const std::string& name)
{
std::string key = section + "=" + name;
// Convert to lower case to make section/name lookups case-insensitive
std::transform(key.begin(), key.end(), key.begin(), ::tolower);
return key;
}
inline int INIReader::ValueHandler(void* user, const char* section, const char* name,
const char* value)
{
INIReader* reader = (INIReader*)user;
std::string key = MakeKey(section, name);
if (reader->_values[key].size() > 0)
reader->_values[key] += "\n";
reader->_values[key] += value;
reader->_sections.insert(section);
return 1;
}
#endif // __INIREADER__
2.test.ini
3.INIReaderTest.cpp
// Example that shows simple usage of the INIReader class
#include <iostream>
#include <sstream>
#include "INIReader.h"
std::string sections(INIReader &reader)
{
std::stringstream ss;
std::set<std::string> sections = reader.Sections();
for (std::set<std::string>::iterator it = sections.begin(); it != sections.end(); ++it)
ss << *it << ",";
return ss.str();
}
int main()
{
INIReader reader("test.ini");
if (reader.ParseError() < 0) {
std::cout << "Can't load 'test.ini'\n";
return 1;
}
std::cout << "Config loaded from 'test.ini': found sections=" << sections(reader)
<< " version="
<< reader.GetInteger("protocol", "version", -1) << ", name="
<< reader.Get("user", "name", "UNKNOWN") << ", email="
<< reader.Get("user", "email", "UNKNOWN") << ", multi="
<< reader.Get("user", "multi", "UNKNOWN") << ", pi="
<< reader.GetReal("user", "pi", -1) << ", active="
<< reader.GetBoolean("user", "active", true) << "\n";
return 0;
}
2.使用ini.h头文件
现代 c++ 的另一个 .ini 解析器（为 cpp17 制作），灵感来自 inih 并进行了扩展。
1.ini.h
#ifndef __INI_H__
#define __INI_H__
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <algorithm>
#include <cctype>
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <iterator>
#include <map>
#include <set>
#include <sstream>
#include <string>
#include <type_traits>
#include <unordered_map>
#include <vector>
namespace inih {
typedef int (*ini_handler)(void* user, const char* section, const char* name,
const char* value);
typedef char* (*ini_reader)(char* str, int num, void* stream);
#define INI_STOP_ON_FIRST_ERROR 1
#define INI_MAX_LINE 2000
#define INI_INITIAL_ALLOC 200
#define MAX_SECTION 50
#define MAX_NAME 50
#define INI_START_COMMENT_PREFIXES ";#"
#define INI_INLINE_COMMENT_PREFIXES ";"
inline static char* rstrip(char* s) {
char* p = s + strlen(s);
while (p > s && isspace((unsigned char)(*--p))) *p = '\0';
return s;
}
inline static char* lskip(const char* s) {
while (*s && isspace((unsigned char)(*s))) s++;
return (char*)s;
}
inline static char* find_chars_or_comment(const char* s, const char* chars) {
int was_space = 0;
while (*s && (!chars || !strchr(chars, *s)) &&
!(was_space && strchr(INI_INLINE_COMMENT_PREFIXES, *s))) {
was_space = isspace((unsigned char)(*s));
s++;
}
return (char*)s;
}
inline static char* strncpy0(char* dest, const char* src, size_t size) {
strncpy(dest, src, size - 1);
dest[size - 1] = '\0';
return dest;
}
inline int ini_parse_stream(ini_reader reader, void* stream,
ini_handler handler, void* user) {
char* line;
size_t max_line = INI_INITIAL_ALLOC;
char* new_line;
size_t offset;
char section[MAX_SECTION] = "";
char prev_name[MAX_NAME] = "";
char* start;
char* end;
char* name;
char* value;
int lineno = 0;
int error = 0;
line = (char*)malloc(INI_INITIAL_ALLOC);
if (!line) {
return -2;
}
#if INI_HANDLER_LINENO
#define HANDLER(u, s, n, v) handler(u, s, n, v, lineno)
#else
#define HANDLER(u, s, n, v) handler(u, s, n, v)
#endif
while (reader(line, (int)max_line, stream) != NULL) {
offset = strlen(line);
while (offset == max_line - 1 && line[offset - 1] != '\n') {
max_line *= 2;
if (max_line > INI_MAX_LINE) max_line = INI_MAX_LINE;
new_line = (char*)realloc(line, max_line);
if (!new_line) {
free(line);
return -2;
}
line = new_line;
if (reader(line + offset, (int)(max_line - offset), stream) == NULL)
break;
if (max_line >= INI_MAX_LINE) break;
offset += strlen(line + offset);
}
lineno++;
start = line;
if (lineno == 1 && (unsigned char)start[0] == 0xEF &&
(unsigned char)start[1] == 0xBB &&
(unsigned char)start[2] == 0xBF) {
start += 3;
}
start = lskip(rstrip(start));
if (strchr(INI_START_COMMENT_PREFIXES, *start)) {
} else if (*start == '[') {
end = find_chars_or_comment(start + 1, "]");
if (*end == ']') {
*end = '\0';
strncpy0(section, start + 1, sizeof(section));
*prev_name = '\0';
} else if (!error) {
error = lineno;
}
} else if (*start) {
end = find_chars_or_comment(start, "=:");
if (*end == '=' || *end == ':') {
*end = '\0';
name = rstrip(start);
value = end + 1;
end = find_chars_or_comment(value, NULL);
if (*end) *end = '\0';
value = lskip(value);
rstrip(value);
strncpy0(prev_name, name, sizeof(prev_name));
if (!HANDLER(user, section, name, value) && !error)
error = lineno;
} else if (!error) {
error = lineno;
}
}
if (error) break;
}
free(line);
return error;
}
inline int ini_parse_file(FILE* file, ini_handler handler, void* user) {
return ini_parse_stream((ini_reader)fgets, file, handler, user);
}
inline int ini_parse(const char* filename, ini_handler handler, void* user) {
FILE* file;
int error;
file = fopen(filename, "r");
if (!file) return -1;
error = ini_parse_file(file, handler, user);
fclose(file);
return error;
}
#endif
#ifndef __INIREADER_H__
#define __INIREADER_H__
// Read an INI file into easy-to-access name/value pairs. (Note that I've gone
// for simplicity here rather than speed, but it should be pretty decent.)
class INIReader {
public:
// Empty Constructor
INIReader(){};
// Construct INIReader and parse given filename. See ini.h for more info
// about the parsing.
INIReader(std::string filename);
// Construct INIReader and parse given file. See ini.h for more info
// about the parsing.
INIReader(FILE* file);
// Return the result of ini_parse(), i.e., 0 on success, line number of
// first error on parse error, or -1 on file open error.
int ParseError() const;
// Return the list of sections found in ini file
const std::set<std::string> Sections() const;
// Return the list of keys in the given section
const std::set<std::string> Keys(std::string section) const;
const std::unordered_map<std::string, std::string> Get(
std::string section) const;
template <typename T = std::string>
T Get(const std::string& section, const std::string& name) const;
template <typename T>
T Get(const std::string& section, const std::string& name,
T&& default_v) const;
template <typename T = std::string>
std::vector<T> GetVector(const std::string& section,
const std::string& name) const;
template <typename T>
std::vector<T> GetVector(const std::string& section,
const std::string& name,
const std::vector<T>& default_v) const;
template <typename T = std::string>
void InsertEntry(const std::string& section, const std::string& name,
const T& v);
template <typename T = std::string>
void InsertEntry(const std::string& section, const std::string& name,
const std::vector<T>& vs);
template <typename T = std::string>
void UpdateEntry(const std::string& section, const std::string& name,
const T& v);
template <typename T = std::string>
void UpdateEntry(const std::string& section, const std::string& name,
const std::vector<T>& vs);
protected:
int _error;
std::unordered_map<std::string,
std::unordered_map<std::string, std::string>>
_values;
static int ValueHandler(void* user, const char* section, const char* name,
const char* value);
template <typename T>
T Converter(const std::string& s) const;
const bool BoolConverter(std::string s) const;
template <typename T>
std::string V2String(const T& v) const;
template <typename T>
std::string Vec2String(const std::vector<T>& v) const;
};
#endif // __INIREADER_H__
#ifndef __INIREADER__
#define __INIREADER__
inline INIReader::INIReader(std::string filename) {
_error = ini_parse(filename.c_str(), ValueHandler, this);
ParseError();
}
inline INIReader::INIReader(FILE* file) {
_error = ini_parse_file(file, ValueHandler, this);
ParseError();
}
inline int INIReader::ParseError() const {
switch (_error) {
case 0:
break;
case -1:
throw std::runtime_error("ini file not found.");
case -2:
throw std::runtime_error("memory alloc error");
default:
throw std::runtime_error("parse error on line no: " +
std::to_string(_error));
}
return 0;
}
inline const std::set<std::string> INIReader::Sections() const {
std::set<std::string> retval;
for (auto const& element : _values) {
retval.insert(element.first);
}
return retval;
}
inline const std::set<std::string> INIReader::Keys(std::string section) const {
auto const _section = Get(section);
std::set<std::string> retval;
for (auto const& element : _section) {
retval.insert(element.first);
}
return retval;
}
inline const std::unordered_map<std::string, std::string> INIReader::Get(
std::string section) const {
auto const _section = _values.find(section);
if (_section == _values.end()) {
throw std::runtime_error("section '" + section + "' not found.");
}
return _section->second;
}
template <typename T>
inline T INIReader::Get(const std::string& section,
const std::string& name) const {
auto const _section = Get(section);
auto const _value = _section.find(name);
if (_value == _section.end()) {
throw std::runtime_error("key '" + name + "' not found in section '" +
section + "'.");
}
std::string value = _value->second;
if constexpr (std::is_same<T, std::string>()) {
return value;
} else if constexpr (std::is_same<T, bool>()) {
return BoolConverter(value);
} else {
return Converter<T>(value);
};
}
template <typename T>
inline T INIReader::Get(const std::string& section, const std::string& name,
T&& default_v) const {
try {
return Get<T>(section, name);
} catch (std::runtime_error& e) {
return default_v;
}
}
template <typename T>
inline std::vector<T> INIReader::GetVector(const std::string& section,
const std::string& name) const {
std::string value = Get(section, name);
std::istringstream out{value};
const std::vector<std::string> strs{std::istream_iterator<std::string>{out},
std::istream_iterator<std::string>()};
try {
std::vector<T> vs{};
for (const std::string& s : strs) {
vs.emplace_back(Converter<T>(s));
}
return vs;
} catch (std::exception& e) {
throw std::runtime_error("cannot parse value " + value +
" to vector<T>.");
}
}
template <typename T>
inline std::vector<T> INIReader::GetVector(
const std::string& section, const std::string& name,
const std::vector<T>& default_v) const {
try {
return GetVector<T>(section, name);
} catch (std::runtime_error& e) {
return default_v;
};
}
template <typename T>
inline void INIReader::InsertEntry(const std::string& section,
const std::string& name, const T& v) {
if (_values[section][name].size() > 0) {
throw std::runtime_error("duplicate key '" + std::string(name) +
"' in section '" + section + "'.");
}
_values[section][name] = V2String(v);
}
template <typename T>
inline void INIReader::InsertEntry(const std::string& section,
const std::string& name,
const std::vector<T>& vs) {
if (_values[section][name].size() > 0) {
throw std::runtime_error("duplicate key '" + std::string(name) +
"' in section '" + section + "'.");
}
_values[section][name] = Vec2String(vs);
}
template <typename T>
inline void INIReader::UpdateEntry(const std::string& section,
const std::string& name, const T& v) {
if (!_values[section][name].size()) {
throw std::runtime_error("key '" + std::string(name) +
"' not exist in section '" + section + "'.");
}
_values[section][name] = V2String(v);
}
template <typename T>
inline void INIReader::UpdateEntry(const std::string& section,
const std::string& name,
const std::vector<T>& vs) {
if (!_values[section][name].size()) {
throw std::runtime_error("key '" + std::string(name) +
"' not exist in section '" + section + "'.");
}
_values[section][name] = Vec2String(vs);
}
template <typename T>
inline std::string INIReader::V2String(const T& v) const {
std::stringstream ss;
ss << v;
return ss.str();
}
template <typename T>
inline std::string INIReader::Vec2String(const std::vector<T>& v) const {
if (v.empty()) {
return "";
}
std::ostringstream oss;
std::copy(v.begin(), v.end() - 1, std::ostream_iterator<T>(oss, " "));
oss << v.back();
return oss.str();
}
template <typename T>
inline T INIReader::Converter(const std::string& s) const {
try {
T v{};
std::istringstream _{s};
_.exceptions(std::ios::failbit);
_ >> v;
return v;
} catch (std::exception& e) {
throw std::runtime_error("cannot parse value '" + s + "' to type<T>.");
};
}
inline const bool INIReader::BoolConverter(std::string s) const {
std::transform(s.begin(), s.end(), s.begin(), ::tolower);
static const std::unordered_map<std::string, bool> s2b{
{"1", true}, {"true", true}, {"yes", true}, {"on", true},
{"0", false}, {"false", false}, {"no", false}, {"off", false},
};
auto const value = s2b.find(s);
if (value == s2b.end()) {
throw std::runtime_error("'" + s + "' is not a valid boolean value.");
}
return value->second;
}
inline int INIReader::ValueHandler(void* user, const char* section,
const char* name, const char* value) {
INIReader* reader = (INIReader*)user;
if (reader->_values[section][name].size() > 0) {
throw std::runtime_error("duplicate key '" + std::string(name) +
"' in section '" + section + "'.");
}
reader->_values[section][name] = value;
return 1;
}
#endif // __INIREADER__
#ifndef __INIWRITER_H__
#define __INIWRITER_H__
class INIWriter {
public:
INIWriter(){};
inline static void write(const std::string& filepath,
const INIReader& reader) {
if (struct stat buf; stat(filepath.c_str(), &buf) == 0) {
throw std::runtime_error("file: " + filepath + " already exist.");
}
std::ofstream out;
out.open(filepath);
if (!out.is_open()) {
throw std::runtime_error("cannot open output file: " + filepath);
}
for (const auto& section : reader.Sections()) {
out << "[" << section << "]\n";
for (const auto& key : reader.Keys(section)) {
out << key << "=" << reader.Get(section, key) << "\n";
}
}
out.close();
}
};
}
#endif
2.config.ini
3.example.cpp
#include <iostream>
#include <string>
#include <typeinfo>
#include <boost/core/demangle.hpp>
#include "ini/ini.h"
using namespace inih;
namespace bc = boost::core;
int main() {
INIReader r{"./test/fixtures/config.ini"};
const auto& v1 = r.Get<std::string>("section1", "any");
const auto& v2 = r.Get<int>("section1", "any");
const auto& v3 = r.Get<double>("section1", "any");
const auto& v4 = r.GetVector<float>("section2", "any_vec");
const auto& v5{r.GetVector<std::string>("section2", "any_vec")};
std::cout << "v1 = " << v1 << ", which is type: " << bc::demangle(typeid(v1).name()) << std::endl;
std::cout << "v2 = " << v2 << ", which is type: " << bc::demangle(typeid(v2).name()) << std::endl;
std::cout << "v3 = " << v3 << ", which is type: " << bc::demangle(typeid(v3).name()) << std::endl;
std::cout << "v4 = "; for (auto& v : v4) std::cout << v << " "; std::cout << ", which is type: " << bc::demangle(typeid(v4).name()) << std::endl;
std::cout << "v5 = "; for (auto& v : v5) std::cout << v << " "; std::cout << ", which is type: " << bc::demangle(typeid(v5).name()) << std::endl;
// section exist, key not exist
r.InsertEntry("section1", "my_custom_key", "hello world");
// section&key not exist
r.InsertEntry("new_section", "key1", 5);
// Dump ini to file
INIWriter::write("output.ini", r);
return 0;
}
3.使用inipp.h头文件
3.1 解析算法
section被设置为空字符串
从文件中读取每一行并从空白处修剪。
- 如果行为空或以;开始然后什么都没发生。
- 否则，如果行以 [ 开头，则section将更改为 [ 和 ] 之间的字符串。如果行不以 ] 结尾，则报告错误。
- 否则，如果行包含 = 符号，则 = 之前的所有字符都被视为变量， = 之后的所有字符都被视为值。两者都被修剪。如果变量之前已经赋值，则会报告错误。否则，将相应的赋值添加到该section。
- 否则，该行被报告为错误。
3.2 默认section算法
将默认section中的每个变量插入到其他每个section中，而不覆盖现有变量。
3.3 Interpolation算法
1.每个section内部，遇到的每个variable都被{section:variable}代替
2.每个{section:variable}都被它的值代替
3.重复上一步，直到无法再进行替换，或者直到达到递归深度（默认为 10）。
3.4 代码实现
1.inipp.h
#pragma once
#include <algorithm>
#include <cctype>
#include <cstring>
#include <functional>
#include <iostream>
#include <list>
#include <vector>
#include <locale>
#include <map>
#include <memory>
#include <sstream>
#include <string>
namespace inipp {
namespace detail {
// trim functions based on http://stackoverflow.com/a/217605
template <class CharT>
inline void ltrim(std::basic_string<CharT> & s, const std::locale & loc) {
s.erase(s.begin(),
std::find_if(s.begin(), s.end(),
[&loc](CharT ch) { return !std::isspace(ch, loc); }));
}
template <class CharT>
inline void rtrim(std::basic_string<CharT> & s, const std::locale & loc) {
s.erase(std::find_if(s.rbegin(), s.rend(),
[&loc](CharT ch) { return !std::isspace(ch, loc); }).base(),
s.end());
}
template <class CharT, class UnaryPredicate>
inline void rtrim2(std::basic_string<CharT>& s, UnaryPredicate pred) {
s.erase(std::find_if(s.begin(), s.end(), pred), s.end());
}
// string replacement function based on http://stackoverflow.com/a/3418285
template <class CharT>
inline bool replace(std::basic_string<CharT> & str, const std::basic_string<CharT> & from, const std::basic_string<CharT> & to) {
auto changed = false;
size_t start_pos = 0;
while ((start_pos = str.find(from, start_pos)) != std::basic_string<CharT>::npos) {
str.replace(start_pos, from.length(), to);
start_pos += to.length();
changed = true;
}
return changed;
}
} // namespace detail
template <typename CharT, typename T>
inline bool extract(const std::basic_string<CharT> & value, T & dst) {
CharT c;
std::basic_istringstream<CharT> is{ value };
T result;
if ((is >> std::boolalpha >> result) && !(is >> c)) {
dst = result;
return true;
}
else {
return false;
}
}
template <typename CharT>
inline bool extract(const std::basic_string<CharT> & value, std::basic_string<CharT> & dst) {
dst = value;
return true;
}
template <typename CharT, typename T>
inline bool get_value(const std::map<std::basic_string<CharT>, std::basic_string<CharT>> & sec, const std::basic_string<CharT> & key, T & dst) {
const auto it = sec.find(key);
if (it == sec.end()) return false;
return extract(it->second, dst);
}
template <typename CharT, typename T>
inline bool get_value(const std::map<std::basic_string<CharT>, std::basic_string<CharT>>& sec, const CharT* key, T& dst) {
return get_value(sec, std::basic_string<CharT>(key), dst);
}
template<class CharT>
class Format
{
public:
// used for generating
const CharT char_section_start;
const CharT char_section_end;
const CharT char_assign;
const CharT char_comment;
// used for parsing
virtual bool is_section_start(CharT ch) const { return ch == char_section_start; }
virtual bool is_section_end(CharT ch) const { return ch == char_section_end; }
virtual bool is_assign(CharT ch) const { return ch == char_assign; }
virtual bool is_comment(CharT ch) const { return ch == char_comment; }
// used for interpolation
const CharT char_interpol;
const CharT char_interpol_start;
const CharT char_interpol_sep;
const CharT char_interpol_end;
Format(CharT section_start, CharT section_end, CharT assign, CharT comment, CharT interpol, CharT interpol_start, CharT interpol_sep, CharT interpol_end)
: char_section_start(section_start)
, char_section_end(section_end)
, char_assign(assign)
, char_comment(comment)
, char_interpol(interpol)
, char_interpol_start(interpol_start)
, char_interpol_sep(interpol_sep)
, char_interpol_end(interpol_end) {}
Format() : Format('[', ']', '=', ';', '$', '{', ':', '}') {}
const std::basic_string<CharT> local_symbol(const std::basic_string<CharT>& name) const {
return char_interpol + (char_interpol_start + name + char_interpol_end);
}
const std::basic_string<CharT> global_symbol(const std::basic_string<CharT>& sec_name, const std::basic_string<CharT>& name) const {
return local_symbol(sec_name + char_interpol_sep + name);
}
};
template<class CharT>
class Ini
{
public:
using String = std::basic_string<CharT>;
using Section = std::map<String, String>;
using Sections = std::map<String, Section>;
Sections sections;
std::list<String> errors;
std::shared_ptr<Format<CharT>> format;
static const int max_interpolation_depth = 10;
Ini() : format(std::make_shared<Format<CharT>>()) {};
Ini(std::shared_ptr<Format<CharT>> fmt) : format(fmt) {};
void generate(std::basic_ostream<CharT>& os) const {
for (auto const & sec : sections) {
os << format->char_section_start << sec.first << format->char_section_end << std::endl;
for (auto const & val : sec.second) {
os << val.first << format->char_assign << val.second << std::endl;
}
os << std::endl;
}
}
void parse(std::basic_istream<CharT> & is) {
String line;
String section;
const std::locale loc{"C"};
while (std::getline(is, line)) {
detail::ltrim(line, loc);
detail::rtrim(line, loc);
const auto length = line.length();
if (length > 0) {
const auto pos = std::find_if(line.begin(), line.end(), [this](CharT ch) { return format->is_assign(ch); });
const auto & front = line.front();
if (format->is_comment(front)) {
}
else if (format->is_section_start(front)) {
if (format->is_section_end(line.back()))
section = line.substr(1, length - 2);
else
errors.push_back(line);
}
else if (pos != line.begin() && pos != line.end()) {
String variable(line.begin(), pos);
String value(pos + 1, line.end());
detail::rtrim(variable, loc);
detail::ltrim(value, loc);
auto & sec = sections[section];
if (sec.find(variable) == sec.end())
sec.emplace(variable, value);
else
errors.push_back(line);
}
else {
errors.push_back(line);
}
}
}
}
void interpolate() {
int global_iteration = 0;
auto changed = false;
// replace each "variable"by"{section:variable}"
for (auto & sec : sections)
replace_symbols(local_symbols(sec.first, sec.second), sec.second);
// replace each "${section:variable}" by its value
do {
changed = false;
const auto syms = global_symbols();
for (auto & sec : sections)
changed |= replace_symbols(syms, sec.second);
} while (changed && (max_interpolation_depth > global_iteration++));
}
void default_section(const Section & sec) {
for (auto & sec2 : sections)
for (const auto & val : sec)
sec2.second.insert(val);
}
void strip_trailing_comments() {
const std::locale loc{ "C" };
for (auto & sec : sections)
for (auto & val : sec.second) {
detail::rtrim2(val.second, [this](CharT ch) { return format->is_comment(ch); });
detail::rtrim(val.second, loc);
}
}
void clear() {
sections.clear();
errors.clear();
}
private:
using Symbols = std::vector<std::pair<String, String>>;
const Symbols local_symbols(const String & sec_name, const Section & sec) const {
Symbols result;
for (const auto & val : sec)
result.emplace_back(format->local_symbol(val.first), format->global_symbol(sec_name, val.first));
return result;
}
const Symbols global_symbols() const {
Symbols result;
for (const auto & sec : sections)
for (const auto & val : sec.second)
result.emplace_back(format->global_symbol(sec.first, val.first), val.second);
return result;
}
bool replace_symbols(const Symbols & syms, Section & sec) const {
auto changed = false;
for (auto & sym : syms)
for (auto & val : sec)
changed |= detail::replace(val.second, sym.first, sym.second);
return changed;
}
};
} // namespace inipp
2.example.ini
3.example.cpp
#include <fstream>
#include "inipp.h"
int main() {
inipp::Ini<char> ini;
std::ifstream is("example.ini");
ini.parse(is);
std::cout << "raw ini file:" << std::endl;
ini.generate(std::cout);
ini.default_section(ini.sections["DEFAULT"]);
ini.interpolate();
std::cout << "ini file after default section and interpolation:" << std::endl;
ini.generate(std::cout);
int compression_level = -1;
inipp::get_value(ini.sections["bitbucket.org"], "CompressionLevel", compression_level);
std::cout << "bitbucket.org compression level: " << compression_level << std::endl;
return 0;
}
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