stdio.c

/*
   File: printf.c

   Copyright (C) 2004  Kustaa Nyholm

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#include "stdio.h"
#include "string.h"

typedef void (*putcf) (void *, char);
static putcf stdout_putf;
static void *stdout_putp;
static char stdout_inited = 0;

#ifdef PRINTF_LONG_SUPPORT

static void
uli2a(unsigned long num, unsigned long base, int uc, char *bf_out)
{
  int n = 0;
  unsigned long d = 1;
  char bf_tmp[12];
  char *bf = bf_tmp;

  while(num / d >= base)
    d *= base;
  while(d != 0L) {
    int dgt = num / d;
    num %= d;
    d /= base;
    if(n || dgt > 0 || d == 0) {
      *bf++ = dgt + (dgt < 10 ? '0' : (uc ? 'A' : 'a') - 10);
      ++n;
    }
  }
  *bf = 0;
  while(n++ < 8 && base == 16) {
    *bf_out++ = '0';
  }
  strcpy(bf_out, bf_tmp);
}
static void
li2a(long num, char *bf)
{
  if(num < 0L) {
    num = -num;
    *bf++ = '-';
  }
  uli2a(num, 10, 0, bf);
}
#endif

#ifdef PRINTF_FLOAT_SUPPORT
unsigned long decimal_array[6] = { 0, 10, 100, 1000, 10000, 100000 };
static void
f2a(double num, int decimals, char *bf)
{
  int i;
  int length;
  char prev = '.';
  int small = 0;

  if(num < 0) {
    num = num * -1;
    *bf++ = '-';
  }

  if(num < 1) {
    small = 1;
    num += 1;
  }

  num = num * decimal_array[decimals % 6];
  uli2a((unsigned long)num, 10, 0, bf);
  length = strlen(bf);
  if(small) {
    bf[0] = '0';
  }
  for(i = length - decimals; i < length; ++i) {
    char tmp = bf[i];
    bf[i] = prev;
    prev = tmp;
  }
  bf[i] = prev;
  bf[i + 1] = 0;
}
#endif /* PRINTF_FLOAT_SUPPORT */

static void
ui2a(unsigned int num, unsigned int base, int uc, char *bf_out)
{
  int n = 0;
  unsigned int d = 1;
  char bf_tmp[12];
  char *bf = bf_tmp;
  while(num / d >= base)
    d *= base;
  while(d != 0) {
    int dgt = num / d;
    num %= d;
    d /= base;
    if(n || dgt > 0 || d == 0) {
      *bf++ = dgt + (dgt < 10 ? '0' : (uc ? 'A' : 'a') - 10);
      ++n;
    }
  }
  *bf = 0;
  while(n++ < 4 && base == 16) {
    *bf_out++ = '0';
  }
  strcpy(bf_out, bf_tmp);
}
static void
i2a(int num, char *bf)
{
  if(num < 0) {
    num = -num;
    *bf++ = '-';
  }
  ui2a(num, 10, 0, bf);
}
static int
a2d(char ch)
{
  if(ch >= '0' && ch <= '9') {
    return ch - '0';
  } else if(ch >= 'a' && ch <= 'f') {
    return ch - 'a' + 10;
  } else if(ch >= 'A' && ch <= 'F') {
    return ch - 'A' + 10;
  } else { return -1;
  }
}
static char
a2i(char ch, const char **src, int base, int *nump)
{
  const char *p = *src;
  int num = 0;
  int digit;
  while((digit = a2d(ch)) >= 0) {
    if(digit > base) {
      break;
    }
    num = num * base + digit;
    ch = *p++;
  }
  *src = p;
  *nump = num;
  return ch;
}
static void
putchw(void *putp, putcf putf, int n, char z, char *bf)
{
  char fc = z ? '0' : ' ';
  char ch;
  char *p = bf;
  while(*p++ && n > 0)
    n--;
  while(n-- > 0)
    putf(putp, fc);
  while((ch = *bf++))
    putf(putp, ch);
}
void
tfp_format(void *putp, putcf putf, const char *fmt, va_list va)
{
  char bf[12];

  char ch;

  while((ch = *(fmt++))) {
    if(ch != '%') {
      putf(putp, ch);
    } else {
      char lz = 0;
#ifdef  PRINTF_LONG_SUPPORT
      char lng = 0;
#endif
      int w = 0;
      ch = *(fmt++);
      if(ch == '0') {
        ch = *(fmt++);
        lz = 1;
      }
      if(ch >= '0' && ch <= '9') {
        ch = a2i(ch, &fmt, 10, &w);
      }
#ifdef  PRINTF_LONG_SUPPORT
      if(ch == 'l') {
        ch = *(fmt++);
        lng = 1;
      }
#endif
      switch(ch) {
      case 0:
        goto abort;
      case 'u': {
#ifdef  PRINTF_LONG_SUPPORT
        if(lng) {
          uli2a(va_arg(va, unsigned long), 10, 0, bf);
        } else
#endif
        ui2a(va_arg(va, unsigned int), 10, 0, bf);
        putchw(putp, putf, w, lz, bf);
        break;
      }
      case 'i':
      case 'd':  {
#ifdef  PRINTF_LONG_SUPPORT
        if(lng) {
          li2a(va_arg(va, unsigned long), bf);
        } else
#endif
        { i2a(va_arg(va, int), bf);
        }
        putchw(putp, putf, w, lz, bf);
        break;
      }
      case 'x': case 'X':
#ifdef  PRINTF_LONG_SUPPORT
        if(lng) {
          uli2a(va_arg(va, unsigned long), 16, (ch == 'X'), bf);
        } else
#endif
        ui2a(va_arg(va, unsigned int), 16, (ch == 'X'), bf);
        putchw(putp, putf, w, lz, bf);
        break;
#ifdef  PRINTF_FLOAT_SUPPORT
      case 'f':
        f2a(va_arg(va, double), 2, bf);
        putchw(putp, putf, w, lz, bf);
        break;
#endif
      case 'c':
        putf(putp, (char)(va_arg(va, int)));
        break;
      case 's':
        putchw(putp, putf, w, 0, va_arg(va, char *));
        break;
      case '%':
        putf(putp, ch);
      default:
        break;
      }
    }
  }
abort:;
}
void
init_printf(void *putp, void (*putf) (void *, char))
{
  stdout_inited = 1;
  stdout_putf = putf;
  stdout_putp = putp;
}
int
tfp_printf(const char *fmt, ...)
{
  va_list va;
  static int inited = 0;
  if(!stdout_inited) {
    return 0;
  }
  va_start(va, fmt);
  tfp_format(stdout_putp, stdout_putf, fmt, va);
  va_end(va);
  return 1;
}
static void
putcp(void *p, char c)
{
  *(*((char **)p))++ = c;
}
int
tfp_sprintf(char *s, const char *fmt, ...)
{
  va_list va;
  char *tmp = s;
  va_start(va, fmt);
  tfp_format(&s, putcp, fmt, va);
  putcp(&s, 0);
  va_end(va);
  return strlen(tmp);
}