json.c

 
#include <math.h>
#include <errno.h>
 
#include <winpr/file.h>
#include <winpr/json.h>
#include <winpr/assert.h>
 
WINPR_JSON* WINPR_JSON_ParseFromFile(const char* filename)
{
  FILE* fp = winpr_fopen(filename, "r");
  if (!fp)
    return NULL;
  WINPR_JSON* json = WINPR_JSON_ParseFromFileFP(fp);
  (void)fclose(fp);
  return json;
}
 
WINPR_JSON* WINPR_JSON_ParseFromFileFP(FILE* fp)
{
  if (!fp)
    return NULL;
 
  if (fseek(fp, 0, SEEK_END) != 0)
    return NULL;
 
  const INT64 size = _ftelli64(fp);
  if (size < 0)
    return NULL;
 
  if (fseek(fp, 0, SEEK_SET) != 0)
    return NULL;
 
  const size_t usize = WINPR_ASSERTING_INT_CAST(size_t, size);
  char* str = calloc(usize + 1, sizeof(char));
  if (!str)
    return NULL;
 
  WINPR_JSON* json = NULL;
  const size_t s = fread(str, sizeof(char), usize, fp);
  if (s == usize)
    json = WINPR_JSON_ParseWithLength(str, usize);
  free(str);
  return json;
}