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c语言支持yaml配置文件通用方法

2022-07-24 01:16:00 【llzhang_fly】

在go语言中使用viper之类的库很方便的处理yaml配置文件，但是在c语言中就比较麻烦，经过一番思索和借助强大的github,发现了一个libyaml c库，但是网上的例子都比较麻烦，而且比较繁琐，就想法作了一个相对比较容易配置的解析应用，可以简单地类似viper 的模式进行配置实现不同的配置文件读取。如你的配置文件很复杂请按格式修改KeyValue 全局变量，欢迎大家一起完善

库请自行下载 GitHub - yaml/libyaml: Canonical source repository for LibYAML

直接上代码

yaml示例文件

%YAML 1.1

---

mqtt:

subtopic: "Control/#"

pubtopic: "bbt"

qos: 1

serveraddress: "tcp://192.168.0.25:1883"

clientid: "kvm_test"

writelog: false

writetodisk: false

outputfile: "./receivedMessages.txt"

hearttime: 30

#ifndef __CONFIG_H__

#define __CONFIG_H__

#ifdef __cplusplus

extern "C" {

#endif

/************************/

/* Minimum YAML version */

/************************/

#define YAML_VERSION_MAJOR 1

#define YAML_VERSION_MINOR 1

#define STRUCT_TYPE_NAME 100

#define INT_TYPE_NAME 101

#define STRING_TYPE_NAME 102

#define BOOL_TYPE_NAME 103

#define FLOAT_TYPE_NAME 104

#define MAP_TYPE_NAME 105

#define LIST_TYPE_NAME 106

typedef struct{

char *key;

void *value;

int valuetype;

char *parent;

}KeyValue,*pKeyValue;

#ifdef __cplusplus

}

#endif

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <stdbool.h>

#include <sys/stat.h>

#include <errno.h>

#include <yaml.h>

#include "config.h"

typedef struct {

char *SUBTOPIC; //string `yaml:"subtopic" mapstructure:"subtopic"` //"topic1"

char *PUBTOPIC; //string `yaml:"pubtopic" mapstructure:"pubtopic"`

int QOS; //byte `yaml:"qos" mapstructure:"qos"` //1

char *SERVERADDRESS; //string `yaml:"serveraddress" mapstructure:"serveraddress"` //= "tcp://mosquitto:1883"

char *CLIENTID; //string `yaml:"clientid" mapstructure:"clientid"` //= "mqtt_subscriber"

int HEARTTIME; //int `yaml:"hearttime" mapstructure:"hearttime"`

// CommandLocalPath string `yam:"commanlocalpath"`

}mqttSection,*pmqttSection;

typedef struct {

mqttSection Mqtt;// `yaml:"mqtt" mapstructure:"mqtt"`

// KVM kvmSection `yaml:"kvm" mapstructure:"kvm"`

}ConfigT;

ConfigT config;

static KeyValue webrtcconfig[]={

{"mqtt",&config,STRUCT_TYPE_NAME,NULL},

{"subtopic",&(config.Mqtt.SUBTOPIC),STRING_TYPE_NAME,"mqtt"},

{"pubtopic",&(config.Mqtt.PUBTOPIC),STRING_TYPE_NAME,"mqtt"},

{"qos",&(config.Mqtt.QOS),INT_TYPE_NAME,"mqtt"},

{"serveraddress",&(config.Mqtt.SERVERADDRESS),STRING_TYPE_NAME,"mqtt"},

{"clientid",&(config.Mqtt.CLIENTID),STRING_TYPE_NAME,"mqtt"},

{"hearttime",&(config.Mqtt.HEARTTIME),INT_TYPE_NAME,"mqtt"},

{NULL,NULL,0,NULL},

};

int printConfig(ConfigT * pconfig){

if(pconfig==NULL) return -1;

printf("mqtt:\r\n");

if(pconfig->Mqtt.SUBTOPIC!=NULL) {printf("subtopic: %s\r\n",pconfig->Mqtt.SUBTOPIC); }

if(pconfig->Mqtt.SUBTOPIC!=NULL) {printf("pubtopic: %s\r\n",pconfig->Mqtt.PUBTOPIC); }

printf("qos: %d\r\n",config.Mqtt.QOS);

if(pconfig->Mqtt.SERVERADDRESS!=NULL) {printf("serveraddress: %s\r\n",pconfig->Mqtt.SERVERADDRESS); }

if(pconfig->Mqtt.CLIENTID!=NULL) {printf("clientid: %s\r\n",pconfig->Mqtt.CLIENTID); }

printf("hearttime: %d\r\n",config.Mqtt.HEARTTIME);

}

int freeConfig(ConfigT * pconfig){

if(pconfig==NULL) return -1;

if(pconfig->Mqtt.SERVERADDRESS!=NULL) {free(pconfig->Mqtt.SERVERADDRESS); }

if(pconfig->Mqtt.CLIENTID!=NULL) {free(pconfig->Mqtt.CLIENTID); }

if(pconfig->Mqtt.SUBTOPIC!=NULL) {free(pconfig->Mqtt.SUBTOPIC); }

}

char currentkey[100];

void getvalue(yaml_event_t event,pKeyValue *ppconfigs){

char *value = (char *)event.data.scalar.value;

pKeyValue pconfig=*ppconfigs;

char *pstringname;

while(pconfig->key!=NULL){

if(currentkey[0]!=0){

if(!strcmp(currentkey,pconfig->key))

{

switch(pconfig->valuetype){

case STRING_TYPE_NAME:

pstringname=strdup(value);

printf("get string value %s\r\n",pstringname);

*((char**)pconfig->value)=pstringname;

memset(currentkey, 0, sizeof(currentkey));

break;

case INT_TYPE_NAME:

*((int*)(pconfig->value))=atoi(value);

memset(currentkey, 0, sizeof(currentkey));

break;

case BOOL_TYPE_NAME:

if(!strcmp(value,"true")) *((bool*)(pconfig->value))=true;

else *((bool*)(pconfig->value))=false;

memset(currentkey, 0, sizeof(currentkey));

break;

case FLOAT_TYPE_NAME:

*((float*)(pconfig->value))=atof(value);

memset(currentkey, 0, sizeof(currentkey));

break;

case STRUCT_TYPE_NAME:

case MAP_TYPE_NAME:

case LIST_TYPE_NAME:

memset(currentkey, 0, sizeof(currentkey));

strncpy(currentkey,value,strlen(value));

break;

default:

break;

}

break;

}

//continue;

}else{

if(!strcmp(value,pconfig->key)){

strncpy(currentkey,pconfig->key,strlen(pconfig->key));

break;

}

pconfig++;

}

int Load_YAML_Config( char *yaml_file, KeyValue *(configs[]) )

{

struct stat filecheck;

yaml_parser_t parser;

yaml_event_t event;

bool done = 0;

unsigned char type = 0;

unsigned char sub_type = 0;

if (stat(yaml_file, &filecheck) != false )

{

printf("[%s, line %d] Cannot open configuration file '%s'! %s", __FILE__, __LINE__, yaml_file, strerror(errno) );

return -1;

}

FILE *fh = fopen(yaml_file, "r");

if (!yaml_parser_initialize(&parser))

{

printf("[%s, line %d] Failed to initialize the libyaml parser. Abort!", __FILE__, __LINE__);

return -1;

}

if (fh == NULL)

{

printf("[%s, line %d] Failed to open the configuration file '%s' Abort!", __FILE__, __LINE__, yaml_file);

return -1;

}

memset(currentkey, 0, sizeof(currentkey));

/* Set input file */

yaml_parser_set_input_file(&parser, fh);

while(!done)

{

if (!yaml_parser_parse(&parser, &event))

{

/* Useful YAML vars: parser.context_mark.line+1, parser.context_mark.column+1, parser.problem, parser.problem_mark.line+1, parser.problem_mark.column+1 */

printf( "[%s, line %d] libyam parse error at line %ld in '%s'", __FILE__, __LINE__, parser.problem_mark.line+1, yaml_file);

}

if ( event.type == YAML_DOCUMENT_START_EVENT )

{

//yaml file first line is version

//%YAML 1.1

//---

yaml_version_directive_t *ver = event.data.document_start.version_directive;

if ( ver == NULL )

{

printf( "[%s, line %d] Invalid configuration file. Configuration must start with \"%%YAML 1.1\"", __FILE__, __LINE__);

}