Hard Disk Usage Miscalculation

[mobejm]

Running Ubuntu Server 22.04.2 LTS on an SSD connected using the provided USB adapter results in two partitions being created:

Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2       440G  3.5G  419G   1% /
/dev/sda1       253M  149M  104M  59% /boot/firmware

The logic used to calculate the hard disk usage seems to assume there is one single partition which results in the hard disk usage being miscalculated.

/*
* get hard disk memory
*/
uint8_t get_hard_disk_memory(uint16_t *diskMemSize, uint16_t *useMemSize)
{
  *diskMemSize = 0;
  *useMemSize = 0;
  uint8_t diskMembuff[10] = {0};
  uint8_t useMembuff[10] = {0};
  FILE *fd = NULL;
  fd=popen("df -l | grep /dev/sda | awk '{printf \"%s\", $(2)}'","r");     <----------
  fgets(diskMembuff,sizeof(diskMembuff),fd);
  fclose(fd);

  fd=popen("df -l | grep /dev/sda | awk '{printf \"%s\", $(3)}'","r");     <----------
  fgets(useMembuff,sizeof(useMembuff),fd);
  fclose(fd);

  *diskMemSize = atoi(diskMembuff)/1024/1024;
  *useMemSize  = atoi(useMembuff)/1024/1024;
}

[ddelegal]

This is also an issue with the latest Raspbian (bookworm). Basically, the size of each sda* partition gets concatenated into a long string and throws the entire calculation off:

Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/sda2      114797372 5308884 103637540   5% /
/dev/sda1         522232   74104    448128  15% /boot/firmware

df -l | grep /dev/sda | awk '{printf "%s", $(2)}'
114797372522232

df -l | grep /dev/sda | awk '{printf "%s", $(3)}'
530888474104