light/src/helpers.c

#include "helpers.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>

LIGHT_BOOL light_readUInt(char const * filename, unsigned int *i)
{
  FILE* fileHandle;
  unsigned int iCopy;

  fileHandle = fopen(filename, "r");

  if(!fileHandle)
  {
    LIGHT_PERMERR("reading");
    return FALSE;
  }

  if(fscanf(fileHandle, "%u", &iCopy) != 1)
  {
    LIGHT_ERR_FMT("Couldn't parse a positive integer number from '%s'", filename);
    fclose(fileHandle);
    return FALSE;
  }
  
  *i = iCopy;

  fclose(fileHandle);
  return TRUE;
}

LIGHT_BOOL light_writeUInt(char const * filename, unsigned int i)
{
  FILE* fileHandle;

  fileHandle = fopen(filename, "w");

  if(!fileHandle)
  {
    LIGHT_PERMERR("writing");
    return FALSE;
  }

  if(fprintf(fileHandle, "%u", i) < 0)
  {
    LIGHT_ERR("fprintf failed");
    fclose(fileHandle);
    return FALSE;
  }

  fclose(fileHandle);
  return TRUE;
}


LIGHT_BOOL light_readULong(char const * filename, unsigned long *i)
{
  FILE* fileHandle;
  unsigned long iCopy;;

  fileHandle = fopen(filename, "r");

  if(!fileHandle)
  {
    LIGHT_PERMERR("reading");
    return FALSE;
  }

  if(fscanf(fileHandle, "%lu", &iCopy) != 1)
  {
    LIGHT_ERR_FMT("Couldn't parse a positive integer number from '%s'", filename);
    fclose(fileHandle);
    return FALSE;
  }
  
  *i = iCopy;

  fclose(fileHandle);
  return TRUE;
}

LIGHT_BOOL light_writeULong(char const * filename, unsigned long i)
{
  FILE* fileHandle;

  fileHandle = fopen(filename, "w");

  if(!fileHandle)
  {
    LIGHT_PERMERR("writing");
    return FALSE;
  }

  if(fprintf(fileHandle, "%lu", i) < 0)
  {
    LIGHT_ERR("fprintf failed");
    fclose(fileHandle);
    return FALSE;
  }

  fclose(fileHandle);
  return TRUE;
}



LIGHT_BOOL light_readString(char const * filename, char *buffer, long* size)
{
  FILE *fileHandle;
  long fileSize;
  long readSize;

  /* Make sure buffer pointer is null */
  if(buffer != NULL)
  {
    LIGHT_ERR("buffer passed to function isn't NULL");
    return FALSE;
  }

  /* Open file */
  fileHandle = fopen(filename, "r");

  if(!fileHandle)
  {
    LIGHT_PERMERR("reading");
    return FALSE;
  }

  /* Get the file size */
  fseek(fileHandle, 0L, SEEK_END);
  fileSize = ftell(fileHandle);
  rewind(fileHandle);

  /* Allocate the string and null-terminate it */
  buffer = malloc(sizeof(char)*(fileSize+1));
  memset(buffer, '\0', fileSize);

  if(buffer == NULL)
  {
    LIGHT_MEMERR();
    fclose(fileHandle);
    return FALSE;
  }

  /* Read the file */
  readSize = fread(buffer, sizeof(char), fileSize, fileHandle);

  if(readSize != fileSize)
  {
    LIGHT_ERR("read error");
    free(buffer);
    fclose(fileHandle);
    return FALSE;
  }
  
  /* Set the size */
  if(size != NULL)
  {
    *size = readSize;
  }

  /* All well, close handle and return TRUE */
  fclose(fileHandle);
  return TRUE;
}

LIGHT_BOOL light_isDir(char const * path)
{
  DIR *dirHandle = opendir(path);

  if(!dirHandle)
  {
    return FALSE;
  }

  closedir(dirHandle);
  return TRUE;
}

LIGHT_BOOL light_isWritable(char const * filename)
{
  FILE* fileHandle = fopen(filename, "r+");

  if(!fileHandle)
  {
    LIGHT_PERMWARN("writing");
    return FALSE;
  }

  fclose(fileHandle);
  return TRUE;
}

LIGHT_BOOL light_isReadable(char const * filename)
{
  FILE* fileHandle = fopen(filename, "r");

  if(!fileHandle)
  {
    LIGHT_PERMWARN("reading");
    return FALSE;
  }

  fclose(fileHandle);
  return TRUE;
}