AP05/uart_utils/read_utils.c

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/select.h>
#include "read_utils.h"
#define PRINT_TIME_TAG
#define DBG_TAG "read_utils"
#define DBG_LVL DBG_INFO
#include "debug_print.h"

/*************************************************************
 * 功能：	设定的时间内读取数据
 **************************************************************/
int read_data_until_time(int fd, char *buffer, int len, int timeout_first, int timeout_interval)
{
	unsigned char c = '\0';
	fd_set fds;
	struct timeval tv;
	int ret;
	int i;

	memset(buffer, 0, len);
	tv.tv_sec = 0;
	tv.tv_usec = timeout_first*1000;
	for(i=0; i<len; i++){
		FD_ZERO(&fds);
		FD_SET(fd, &fds);
		//ret = select(FD_SETSIZE, &fds, NULL, NULL, &tv);
		ret = select(FD_SETSIZE, &fds, NULL, NULL, 0);
		if(ret < 0){
			LOG_I("%s:seclect error\n",__func__);
			i = -1;
			break;
		}else if(ret > 0){
			if(FD_ISSET(fd, &fds)){
				ret = read(fd, &c, 1);
				if(ret < 0){
					LOG_I("read error\n");
					i = -1;
					break;
				}else if(ret == 0){
					//LOG_I("end of file\n");
					break;
				}else{
					buffer[i] = c;
				}
			}
			tv.tv_sec = 0;
			tv.tv_usec = timeout_interval*1000;
		}else{
			//LOG_I("read time out\n");
			break;
		}
	}
	return i;
}

/*************************************************************
 * 功能：	读一串至截止字符的字符串，在设定的时间内读不到数据则函数返回
 **************************************************************/
int read_data_until_char(int fd, char *buffer, int len, char until, int timeout_first, int timeout_interval)
{
	unsigned char c = '\0';
	fd_set fds;
	struct timeval tv;
	int ret;
	int i;

	memset(buffer, 0, len);
	for(i=0; i<len; i++){
		tv.tv_sec = 0;
		tv.tv_usec = timeout_first*1000;
		FD_ZERO(&fds);
		FD_SET(fd, &fds);
		//ret = select(FD_SETSIZE, &fds, NULL, NULL, &tv);
		ret = select(FD_SETSIZE, &fds, NULL, NULL, 0);
		if(ret < 0){
			LOG_I("%s:seclect error\n",__func__);
			i = -1;
			break;
		}else if(ret > 0){
			if(FD_ISSET(fd, &fds)){
				ret = read(fd, &c, 1);
				if(ret < 0){
					LOG_I("read error\n");
					i = -1;
					break;
				}else if(ret == 0){
					LOG_I("end of file\n");
				}else{
					buffer[i] = c;
#if 0	
					LOG_D("i= %d\n", i);
					LOG_D("\t,[%#x], <%c>\n", c, c);
#endif				
                    tv.tv_sec = 0;
                    tv.tv_usec = timeout_interval*1000;
					if(c == until){
						i++;
						break;
					}
				}
			}
		}else{
			//LOG_I("read time out\n");
		}
	}
	return i;
}

/*************************************************************
 * 功能：	读一串至截止字符串的字符串，在设定的时间内读不到数据则函数返回
 **************************************************************/
int read_data_until_str(int fd, char *buffer, int len, char *until, int until_len, int timeout_first, int timeout_interval)
{
	unsigned char c = '\0';
	fd_set fds;
	struct timeval tv;
	int ret;
	int i;

	memset(buffer, 0, len);
	for(i=0; i<len; i++){
		tv.tv_sec = 0;
		tv.tv_usec = timeout_first*1000;
		FD_ZERO(&fds);
		FD_SET(fd, &fds);
		//ret = select(FD_SETSIZE, &fds, NULL, NULL, &tv);
		ret = select(FD_SETSIZE, &fds, NULL, NULL, 0);
		if(ret < 0){
			LOG_I("%s:seclect error\n",__func__);
			i = -1;
			break;
		}else if(ret > 0){
			if(FD_ISSET(fd, &fds)){
				ret = read(fd, &c, 1);
				if(ret < 0){
					LOG_I("read error\n");
					i = -1;
					break;
				}else if(ret == 0){
					LOG_I("end of file\n");
				}else{
					buffer[i] = c;
#if 0
					LOG_I("i= %d\n", i);
					LOG_I("\t,[%#x], <%c>\n", c, c);
#endif				
                    tv.tv_sec = 0;
                    tv.tv_usec = timeout_interval*1000;
                    if((i+1) >= until_len) {
                        if(strncmp(buffer+i+1-until_len, until, until_len) == 0){
                            i++;
                            break;
                        }
                    }
				}
			}
		}else{
			//LOG_I("read time out\n");
		}
	}
	return i;
}