C++ 配置文件类的封装

有时开发项目，需要对数据库等配置放到程序对外面作为配置文件，配置文件对读取

ConfigManager.h

/*
* ConfigManager.h
*
*  Created on: 2018年7月28日
*      Author: oftenlin
*/

#ifndef CONFIGMANAGER_H_
#define CONFIGMANAGER_H_
#define SIZE_FILENAME 50

class ConfigManager{
public:
ConfigManager(const char *filename){ConfigFileLoad(filename);};
~ConfigManager(){ConfigFileFree();};
//加载ini文件至内存

char gFilename[SIZE_FILENAME];
char *gBuffer;
int gBuflen;
int ConfigFileLoad(const char *filename);
//释放ini文件所占资源
void ConfigFileFree();
int FindSection(const char *section, char **sect1, char **sect2, char **cont1, char **cont2, char **nextsect);
//获取字符串，不带引号
int GetString(const char *section, const char *key, char *value, int size, const char *defvalue);
//获取整数值
int GetInt(const char *section, const char *key, int defvalue);
//获取浮点数
double GetDouble(const char *section, const char *key, double defvalue);
int GetValue(const char *section, const char *key, char *value, int maxlen, const char *defvalue);
//设置字符串：若value为NULL，则删除该key所在行，包括注释
int SetString(const char *section, const char *key, const char *value);
//设置整数值：base取值10、16、8，分别表示10、16、8进制，缺省为10进制
int SetInt(const char *section, const char *key, int value, int base=10);
//    int iniGetIP(const char *section, const char *key, BasicHashTable *hashtable, int size, const char *defvalue);
};

#endif /* CONFIGMANAGER_H_ */

ConfigManager.cpp

/*
* ConfigManager.cpp
* Created on: 2018年7月28日
* Author: oftenlin
*/

#include <ctype.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "ConfigManager.h"

#define  SIZE_LINE  100

#define fmin(x, y)      (x <= y) ? x : y

typedef enum _ELineType_ {
LINE_IDLE,      //未处理行
LINE_ERROR,     //错误行
LINE_EMPTY,     //空白行或注释行
LINE_SECTION,   //节定义行
LINE_VALUE      //值定义行
} ELineType ;

//去除串首尾空格，原串被改写
char *StrStrip(char *s)
{
size_t size;
char *p1, *p2;

size = strlen(s);
if (!size)
return s;

p2 = s + size - 1;

while ((p2 >= s) && isspace(*p2))
p2 --;
*(p2 + 1) = '\0';

p1 = s;
while (*p1 && isspace(*p1))
p1 ++;
if (s != p1)
memmove(s, p1, p2 - p1 + 2);
return s;
}

//不区分大小写比较字符串
int StriCmp(const char *s1, const char *s2)
{
int ch1, ch2;
do
{
ch1 = (unsigned char)*(s1++);
if ((ch1 >= 'A') && (ch1 <= 'Z'))
ch1 += 0x20;

ch2 = (unsigned char)*(s2++);
if ((ch2 >= 'A') && (ch2 <= 'Z'))
ch2 += 0x20;
} while ( ch1 && (ch1 == ch2) );
return(ch1 - ch2);
}

//取一行
//输入：数据区(指针及长度)
//输出：行类型、有效内容串(去首尾空格)、注释首、注释尾、下一行首(行尾与下一行首间为换行符)
//      有效内容位置为[buf, rem1)
int GetLine(char *buf, int buflen, char *content, char **rem1, char **rem2, char **nextline)
{
char *cont1, *cont2;
int cntblank, cntCR, cntLF;     //连续空格、换行符数量
char isQuot1, isQuot2;          //引号
int i;
char *p;

//首先断行断注释，支持如下换行符：\r、\n、\r\n、\n\r
cntblank = 0;
cntCR = cntLF = 0;
isQuot1 = isQuot2 = 0;
cont1 = *rem1 = 0;
content[0] = 0;
for (i = 0, p = buf; i < buflen; i ++, p ++)
{
if (*p == 0) {
p ++;
break;
}
//2个CR或LF，行结束
if (cntCR == 2 || cntLF == 2) {
p --;   //回溯1
break;
}
//CR或LF各1个之后任意字符，行结束
if (cntCR + cntLF >= 2) {
break;
}
//CR或LF之后出现其它字符，行结束
if ((cntCR || cntLF) && *p != '\r' && *p != '\n')
break;

switch (*p) {
case '\r':
cntCR ++;
break;
case '\n':
cntLF ++;
break;
case '\'':
if (!isQuot2)
isQuot1 = 1 - isQuot1;
break;
case '\"':
if (!isQuot1)
isQuot2 = 1 - isQuot2;
break;
case ';':
case '#':
if (isQuot1 || isQuot2)
break;
if (*rem1 == NULL)
*rem1 = p - cntblank;
break;
default:
if (isspace((unsigned char)*p)) {
cntblank ++;
} else {
cntblank = 0;
if ((*rem1 == NULL) && (cont1 == NULL))
cont1 = p;
}
break;
}
}

*nextline = p;
*rem2 = p - cntCR - cntLF;
if (*rem1 == NULL)
*rem1 = *rem2;
cont2 = *rem1 - cntblank;

if (cont1 == NULL) {
cont1 = cont2;
return LINE_EMPTY;
}

i = (int)(cont2 - cont1);
if (i >= SIZE_LINE)
return LINE_ERROR;

//内容头尾已无空格
memcpy(content, cont1, i);
content[i] = 0;

if (content[0] == '[' && content[i - 1] == ']')
return LINE_SECTION;
if (strchr(content, '=') != NULL)
return LINE_VALUE;

return LINE_ERROR;
}

//取一节section
//输入：节名称
//输出：成功与否、节名称首、节名称尾、节内容首、节内容尾(含换行)、下一节首(节尾与下一节首间为空行或注释行)
int ConfigManager::FindSection(const char *section, char **sect1, char **sect2, char **cont1, char **cont2, char **nextsect)
{
int type;
char content[SIZE_LINE];
char *rem1, *rem2, *nextline;

char *p;
char *empty;
int uselen = 0;
char found = 0;

if (gBuffer == NULL) {
return 0;
}

while (gBuflen - uselen > 0) {
p = gBuffer + uselen;
type = GetLine(p, gBuflen - uselen, content, &rem1, &rem2, &nextline);
uselen += (int)(nextline - p);

if (LINE_SECTION == type) {
if (found || section == NULL) break;        //发现另一section
content[strlen(content) - 1] = 0;           //去尾部]
StrStrip(content + 1);                      //去首尾空格
if (StriCmp(content + 1, section) == 0) {
found = 1;
*sect1 = p;
*sect2 = rem1;
*cont1 = nextline;
}
empty = nextline;
} else
if (LINE_VALUE == type) {
if (!found && section == NULL) {
found = 1;
*sect1 = p;
*sect2 = p;
*cont1 = p;
}
empty = nextline;
}
}

if (!found) return 0;

*cont2 = empty;
*nextsect = nextline;
return 1;
}

//从一行取键、值
//输入：内容串(将被改写)
//输出：键串、值串
void GetKeyValue(char *content, char **key, char **value)
{
char *p;

p = strchr(content, '=');
*p = 0;
StrStrip(content);
StrStrip(p + 1);
*key = content;
*value = p + 1;
}

//释放ini文件所占资源
void ConfigManager:: ConfigFileFree()
{
if (gBuffer != NULL) {
free(gBuffer);
gBuffer = 0;
gBuflen = 0;
}
}

//加载ini文件至内存
int ConfigManager::ConfigFileLoad(const char *filename)
{
FILE *file;
int len;

//iniFileFree();
if (strlen(filename) >= sizeof(gFilename))
return 0;
strcpy(gFilename, filename);

file = fopen(gFilename, "ab+");
if (file == NULL)
return 0;

fseek(file, 0, SEEK_END);
len = ftell(file);
gBuffer =(char *) malloc(len);
if (gBuffer == NULL) {
fclose(file);
return 0;
}

fseek(file, 0, SEEK_SET);
len = fread(gBuffer, 1, len, file);
fclose(file);
gBuflen = len;
return 1;
}

//读取值原始串
int ConfigManager::GetValue(const char *section, const char *key, char *value, int maxlen, const char *defvalue)
{
int type;
char content[SIZE_LINE];
char *rem1, *rem2, *nextline;
char *key0, *value0;

char *p;
int uselen = 0;
char found = 0;
int len;

if (gBuffer == NULL || key == NULL) {
if (value != NULL)
value[0] = 0;
return 0;
}

while (gBuflen - uselen > 0) {
p = gBuffer + uselen;
type = GetLine(p, gBuflen - uselen, content, &rem1, &rem2, &nextline);
uselen += (int)(nextline - p);

if (LINE_SECTION == type) {
if (found || section == NULL) break;        //发现另一section
content[strlen(content) - 1] = 0;           //去尾部]
StrStrip(content + 1);                      //去首尾空格
if (StriCmp(content + 1, section) == 0) {
found = 1;
}
} else
if (LINE_VALUE == type) {
if (!found && section == NULL) {
found = 1;
}
if (!found)
continue;
GetKeyValue(content, &key0, &value0);
if (StriCmp(key0, key) == 0) {
len = strlen(value0);
if (len == 0) break;        //空值视为无效
if (value != NULL) {
len = fmin(len, maxlen - 1);
strncpy(value, value0, len);
value[len] = 0;
}
//  printf("value = %s\n",value);
return 1;
}
}
}

//未发现键值取缺省
if (value != NULL) {
if (defvalue != NULL) {
len = fmin(strlen(defvalue), maxlen - 1);
strncpy(value, defvalue, len);
value[len] = 0;
SetString(section, key, defvalue);
} else {
value[0] = 0;
}
}
return 0;
}

//获取字符串，不带引号
int ConfigManager::GetString(const char *section, const char *key, char *value, int maxlen, const char *defvalue)
{
int ret;
int len;

ret = GetValue(section, key, value, maxlen, defvalue);
if (!ret)
return ret;

//去首尾空格
len = strlen(value);
if (value[0] == '\'' && value[len - 1] == '\'') {
value[len - 1] = 0;
memmove(value, value + 1, len - 1);
} else
if (value[0] == '\"' && value[len - 1] == '\"') {
value[len - 1] = 0;
memmove(value, value + 1, len - 1);
}
return ret;
}

//获取整数值
int ConfigManager::GetInt(const char *section, const char *key, int defvalue)
{
char valstr[64];

if (GetValue(section, key, valstr, sizeof(valstr), NULL))
return (int)strtol(valstr, NULL, 0);
SetInt(section, key,defvalue,10);
return defvalue;
}

//获取浮点数
double ConfigManager::GetDouble(const char *section, const char *key, double defvalue)
{
char valstr[64];

if (GetValue(section, key, valstr, sizeof(valstr), NULL))
return (int)atof(valstr);
return defvalue;
}

//设置字符串：若value为NULL，则删除该key所在行，包括注释
int ConfigManager::SetString(const char *section, const char *key, const char *value)
{
FILE *file;
char *sect1, *sect2, *cont1, *cont2, *nextsect;
char *p;
int len, type;
char content[SIZE_LINE];
char *key0, *value0;
char *rem1, *rem2, *nextline;

if (gBuffer == NULL) {
return 0;
}

if (FindSection(section, &sect1, &sect2, &cont1, &cont2, &nextsect) == 0)
{
//未找到节
//value无效则返回
if (value == NULL)
return 0;
//在文件尾部添加
file = fopen(gFilename, "ab");
if (file == NULL)
return 0;
fprintf(file, "\r\n[%s]\r\n%s=%s;\r\n", section, key, value);
fclose(file);
ConfigFileLoad(gFilename);
return 1;
}

//找到节，则节内查找key
p = cont1;
len = (int)(cont2 - cont1);
while (len > 0) {
type = GetLine(p, len, content, &rem1, &rem2, &nextline);
if (LINE_VALUE == type) {
GetKeyValue(content, &key0, &value0);
if (StriCmp(key0, key) == 0) {
//找到key
file = fopen(gFilename, "wb");
if (file == NULL)
return 0;
len = (int)(p - gBuffer);
fwrite(gBuffer, 1, len, file);                  //写入key之前部分
if (value == NULL) {
//value无效，删除
len = (int)(nextline - gBuffer);            //整行连同注释一并删除
} else {
//value有效，改写
fprintf(file, "%s=%s", key, value);
len = (int)(rem1 - gBuffer);                //保留尾部原注释!
}
fwrite(gBuffer + len, 1, gBuflen - len, file);  //写入key所在行含注释之后部分
fclose(file);
ConfigFileLoad(gFilename);
return 1;
}
}

len -= (int)(nextline - p);
p = nextline;
}

//未找到key

//value无效则返回
if (value == NULL)
return 0;

//在文件尾部添加
file = fopen(gFilename, "wb");
if (file == NULL)
return 0;
len = (int)(cont2 - gBuffer);
fwrite(gBuffer, 1, len, file);                  //写入key之前部分
fprintf(file, "%s=%s;\r\n", key, value);
fwrite(gBuffer + len, 1, gBuflen - len, file);  //写入key之后部分
fclose(file);
ConfigFileLoad(gFilename);
return 1;
}

//设置整数值：base取值10、16、8，分别表示10、16、8进制，缺省为10进制
int ConfigManager::SetInt(const char *section, const char *key, int value, int base)
{
char valstr[64];

switch (base) {
case 16:
sprintf(valstr, "0x%x", value);
return SetString(section, key, valstr);
case 8:
sprintf(valstr, "0%o", value);
return SetString(section, key, valstr);
default:    //10
sprintf(valstr, "%d", value);
return SetString(section, key, valstr);
}
}

读取方法

#include "utils/ConfigManager.h"
int main() {
ConfigManager *configManger=new
ConfigManager("config.ini");
char *general_sect="general";
int city = configManger->GetInt(general_sect,"cityid" ,1);
//整型数字的获取
　　

}

配置文件

[general]
cityid=1;
dbhost=127.0.0.1;
port=3306;
user=root;
passwd=root;