PostgreSQL Source Code  git master
strtof.c File Reference
#include "c.h"
#include <float.h>
#include <math.h>
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Functions

float pg_strtof (const char *nptr, char **endptr)
 

Function Documentation

◆ pg_strtof()

float pg_strtof ( const char *  nptr,
char **  endptr 
)

Definition at line 30 of file strtof.c.

31 {
32  int caller_errno = errno;
33  float fresult;
34 
35  errno = 0;
36  fresult = (strtof) (nptr, endptr);
37  if (errno)
38  {
39  /* On error, just return the error to the caller. */
40  return fresult;
41  }
42  else if ((*endptr == nptr) || isnan(fresult) ||
43  ((fresult >= FLT_MIN || fresult <= -FLT_MIN) && !isinf(fresult)))
44  {
45  /*
46  * If we got nothing parseable, or if we got a non-0 non-subnormal
47  * finite value (or NaN) without error, then return that to the caller
48  * without error.
49  */
50  errno = caller_errno;
51  return fresult;
52  }
53  else
54  {
55  /*
56  * Try again. errno is already 0 here.
57  */
58  double dresult = strtod(nptr, NULL);
59 
60  if (errno)
61  {
62  /* On error, just return the error */
63  return fresult;
64  }
65  else if ((dresult == 0.0 && fresult == 0.0) ||
66  (isinf(dresult) && isinf(fresult) && (fresult == dresult)))
67  {
68  /* both values are 0 or infinities of the same sign */
69  errno = caller_errno;
70  return fresult;
71  }
72  else if ((dresult > 0 && dresult <= FLT_MIN && (float) dresult != 0.0) ||
73  (dresult < 0 && dresult >= -FLT_MIN && (float) dresult != 0.0))
74  {
75  /* subnormal but nonzero value */
76  errno = caller_errno;
77  return (float) dresult;
78  }
79  else
80  {
81  errno = ERANGE;
82  return fresult;
83  }
84  }
85 }