PBC库传入参数文件问题

配置不同类型的椭圆曲线，需要修改配对类型。

PBC的param目录下有好多种：

PBC手册是这样写的

Chapter 5. Param functions

Pairings are initialized from pairing parameters, which are objects of type pbc_param_t. Some applications can ignore this data type because pairing_init_set_str() handles it behind the scenes:it reads a string as a pbc_param_t, then initializes a pairing with these parameters.

• int pbc_param_init_set_str(pbc_param_t par, const char *s)

Initializes pairing parameters from the string s. Returns 0 if successful, 1 otherwise.

• int pbc_param_init_set_buf(pbc_param_t par, const char *s, size_t len)          

 Same, but read at most len bytes. If len is 0, it behaves as the previous function. Returns 0 if successful, 

• void pbc_param_out_str(FILE *stream, pbc_param_t p)

Write pairing parameters to ’stream’ in a text format.

• void pbc_param_clear(pbc_param_t p)

Clear p. Call after p is no longer needed.

可以使用的有以下三种：

（1）Windows下直接调用的只有A，D,F三种类型的曲线

pairing_t pairing;
a_param_input(pairing);
           

（2）产生动态配参数

pairing_t pairing;
a_param_t w;
a_param_init(w);
a_param_gen(w,160,512);//取160bit，512bit最佳
pairing_init_a_param(pairing,w);
           
                
 

 
（3）自己写的一个pbc_new.h头文件
 

       
#include <stdio.h>
#include "pbc.h"
static inline void pbc_demo_pairing_init(pairing_t pairing, char* filename) {  
	char s[16384];  
	FILE *fp;  
	unsigned int count;
	fp = fopen(filename, "r");  
	if (!fp){  
      printf("error opening %s", filename);  
	}  
      count = fread(s, 1, 16384, fp);  
	if (!count){  
      printf("input error");  
	 }  
	fclose(fp);  
	pairing_init_inp_buf(pairing, s, count); }
           
        


 
主函数main（）里的调用代码：
 

       
#define F_PATH "d:\\a.param" 我放在D盘根目录下
	//char* c_filepath = "d:\\a.param";  
    pbc_demo_pairing_init(pairing, F_PATH);  //pbc_new.h