#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include "debug.h"

int sysfs_read_str(char *sysfs_file,char *buf,size_t bufsize)
{
 int sysfs_handle;
 size_t datalen;

 DEBUG1_SYSFS("Reading sysfs file %s\n",sysfs_file);

// Open the file
 sysfs_handle=open(sysfs_file,O_RDONLY);
 DEBUG2_SYSFS("Open returned %d\n",sysfs_handle);
 if (sysfs_handle<0) return -1;

// Read the content of the file
 datalen=read(sysfs_handle,buf,bufsize);
 HEXDUMP2_SYSFS(buf,datalen);
 close(sysfs_handle);
 buf[datalen]=0;

// Strip newline
 if (buf[datalen-1]=='\n')
 {
  DEBUG2_SYSFS("Newline stripped\n");
  datalen--;
  buf[datalen]=0;
 }

 return datalen;
}

long int sysfs_read_long_int(char *sysfs_file)
{
 char buf[255];
 int datalen;

// Read data
 datalen=sysfs_read_str(sysfs_file,buf,sizeof(buf));
 if (datalen<0) return 0;

// Convert to long int
 return strtoll((char*)&buf,NULL,10);
}

int sysfs_write_str(char *sysfs_file,char *value,long int checkdelay)
{
 int sysfs_handle;
 size_t len;
 char buf[255];

 DEBUG1_SYSFS("Writing %s to sysfs file %s\n",value,sysfs_file);

// Open the file
 sysfs_handle=open(sysfs_file,O_WRONLY);
 DEBUG2_SYSFS("Open returned %d\n",sysfs_handle);
 if (sysfs_handle<0) return -1;

// Write the data
 len=write(sysfs_handle,value,strlen(value));
 close(sysfs_handle);
 DEBUG2_SYSFS("Written %zd bytes\n",len);

// What if instructed to
 if (checkdelay>0) usleep(checkdelay);

// Validate we actually set what we want to set
 sysfs_read_str(sysfs_file,buf,sizeof(buf));
 DEBUG2_SYSFS("Content is now %s\n",buf);

 if (strncmp(value,buf,255)!=0)
 {
  DEBUG2_SYSFS("Set failed\n");
  return -1;
 }
 DEBUG2_SYSFS("Set successfull\n");

 return 0;
}