source: trunk/dll/commafmt.c@ 859

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

  $Id: commafmt.c 859 2007-11-05 22:32:39Z 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
  20 Aug 07 GKY Move #pragma alloc_text to end for OpenWatcom compat

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

/*
   **  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.
 */

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

  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;
}

#pragma alloc_text(MISC8,commafmt,CommaFmtU64)