/***********************************************************************

  $Id: commafmt.c 551 2007-02-28 01:33:51Z gyoung $

  Command formatting tools

  Copyright (c) 1993-98 M. Kimes
  Copyright (c) 2004, 2005 Steven H. Levine

  06 Jan 04 SHL Disable hundfmt, clean commafmt
  25 May 05 SHL Drop hundfmt
  25 May 05 SHL Add CommaFmtULL, CommaFmtUL

***********************************************************************/

/*
   **  COMMAFMT.C
   **  Public domain by Bob Stout
   **
   **  Notes:  1. Use static buffer to eliminate error checks on buffer overflow
   **             and reduce code size.
   **          2. By making the numeric argument a long and prototyping it before
   **             use, passed numeric arguments will be implicitly cast to longs
   **             thereby avoiding int overflow.
   **          3. Use the thousands grouping and thousands separator from the
   **             ANSI locale to make this more robust.
 */

#pragma alloc_text(MISC8,commafmt,CommaFmtU64)

#define INCL_LONGLONG
#include <os2.h>

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

size_t commafmt(char *pszBuf,	// Output buffer
		UINT cBufSize,	// Buffer size, including nul
		long lNumber)	// Number to convert
{
  UINT cChars = 1;		// Number of characters generated (excluding nul)
  UINT cDigits = 1;		// For commas
  INT sign = 1;

  char *pch = pszBuf + cBufSize - 1;

  if (cBufSize < 2)
    goto ABORT;

  *pch-- = 0;				// Stuff terminator
  --cBufSize;
  if (lNumber < 0) {
    sign = -1;
    lNumber = -lNumber;
  }

  for (; cChars <= cBufSize; ++cChars, ++cDigits) {
    *pch-- = (CHAR) (lNumber % 10 + '0');
    lNumber /= 10;
    if (!lNumber)
      break;
    if (cDigits % 3 == 0) {
      *pch-- = ',';
      ++cChars;
    }
    if (cChars >= cBufSize)
      goto ABORT;
  }					// for

  if (sign < 0) {
    if (cBufSize == 0)
      goto ABORT;
    *pch-- = '-';
    ++cChars;
  }

  strcpy(pszBuf, ++pch);		// Left align

  return cChars;

ABORT:
  *pszBuf = 0;
  return 0;
}

//=== CommaFmtULL: format long long number with commas and SI unit suffix ===

size_t CommaFmtULL(char *pszBuf,	// Output buffer
		   UINT cBufSize,	// Buffer size, including nul
		   ULONGLONG ullNumber,	// Number to convert
		   CHAR chPreferred)	// Preferred suffix, blank, K, M
{
  CHAR chSuffix = ' ';
  size_t c;

  if (ullNumber >= 1ULL << 31 || (chPreferred != ' ' && ullNumber >= 1024)) {
    ullNumber = (ullNumber + 1023) >> 10;
    chSuffix = 'K';
    if (ullNumber >= 1ULL << 31 || (chPreferred == 'M' && ullNumber >= 1024)) {
      ullNumber = (ullNumber + 1023) >> 10;
      chSuffix = 'M';
    }
  }

  c = commafmt(pszBuf, cBufSize, (LONG) ullNumber);

  if (chSuffix != ' ') {
    if (c + 4 > cBufSize) {
      *pszBuf = 0;
      c = 0;
    }
    else {
      pszBuf += c;
      *pszBuf++ = chSuffix;
      *pszBuf++ = 'i';
      *pszBuf++ = 'B';
      c += 3;
      *pszBuf = 0;
    }
  }
  return c;
}

//=== CommaFmtUL: format unsigned long number with commas and SI unit suffix ===

size_t CommaFmtUL(char *pszBuf,	// Output buffer
		  UINT cBufSize,	// Buffer size, including nul
		  ULONG ulNumber,	// Number to convert
		  CHAR chPreferred)	// Preferred suffix, blank, K, M
{
  CHAR chSuffix = ' ';
  size_t c;

  if (ulNumber >= 1ULL << 31 || (chPreferred != ' ' && ulNumber >= 1024)) {
    ulNumber = (ulNumber + 1023) >> 10;
    chSuffix = 'K';
    if (ulNumber >= 1ULL << 31 || (chPreferred == 'M' && ulNumber >= 1024)) {
      ulNumber = (ulNumber + 1023) >> 10;
      chSuffix = 'M';
    }
  }

  c = commafmt(pszBuf, cBufSize, ulNumber);

  if (chSuffix != ' ') {
    if (c + 4 > cBufSize) {
      *pszBuf = 0;
      c = 0;
    }
    else {
      pszBuf += c;
      *pszBuf++ = chSuffix;
      *pszBuf++ = 'i';
      *pszBuf++ = 'B';
      c += 3;
      *pszBuf = 0;
    }
  }
  return c;
}