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/*
* Copyright (C) 2001 MontaVista Software Inc.
* Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include "print.h"
/* macros */
#define IsDigit(x) ( ((x) >= '0') && ((x) <= '9') )
#define Ctod(x) ( (x) - '0')
/* forward declaration */
extern int PrintChar(char *, char, int, int);
extern int PrintString(char *, char *, int, int);
extern int PrintNum(char *, unsigned long, int, int, int, int, char, int);
/* private variable */
static const char theFatalMsg[] = "fatal error in lp_Print!";
/* -*-
* A low level printf() function.
*/
void
lp_Print(void (*output)(void *, char *, int),
void * arg,
char *fmt,
va_list ap)
{
#define OUTPUT(arg, s, l) \
{ if (((l) < 0) || ((l) > LP_MAX_BUF)) { \
(*output)(arg, (char*)theFatalMsg, sizeof(theFatalMsg)-1); for(;;); \
} else { \
(*output)(arg, s, l); \
} \
}
char buf[LP_MAX_BUF];
char c;
char *s;
long int num;
int longFlag;
int negFlag;
int width;
int prec;
int ladjust;
char padc;
int length;
for(;;) {
{
/* scan for the next '%' */
char *fmtStart = fmt;
while ( (*fmt != '\0') && (*fmt != '%')) {
fmt ++;
}
/* flush the string found so far */
OUTPUT(arg, fmtStart, fmt-fmtStart);
/* are we hitting the end? */
if (*fmt == '\0') break;
}
/* we found a '%' */
fmt ++;
/* check for long */
if (*fmt == 'l') {
longFlag = 1;
fmt ++;
} else {
longFlag = 0;
}
/* check for other prefixes */
width = 0;
prec = -1;
ladjust = 0;
padc = ' ';
if (*fmt == '-') {
ladjust = 1;
fmt ++;
}
if (*fmt == '0') {
padc = '0';
fmt++;
}
if (IsDigit(*fmt)) {
while (IsDigit(*fmt)) {
width = 10 * width + Ctod(*fmt++);
}
}
if (*fmt == '.') {
fmt ++;
if (IsDigit(*fmt)) {
prec = 0;
while (IsDigit(*fmt)) {
prec = prec*10 + Ctod(*fmt++);
}
}
}
/* check format flag */
negFlag = 0;
switch (*fmt) {
case 'b':
if (longFlag) {
num = va_arg(ap, long int);
} else {
num = va_arg(ap, int);
}
length = PrintNum(buf, num, 2, 0, width, ladjust, padc, 0);
OUTPUT(arg, buf, length);
break;
case 'd':
case 'D':
if (longFlag) {
num = va_arg(ap, long int);
} else {
num = va_arg(ap, int);
}
if (num < 0) {
num = - num;
negFlag = 1;
}
length = PrintNum(buf, num, 10, negFlag, width, ladjust, padc, 0);
OUTPUT(arg, buf, length);
break;
case 'o':
case 'O':
if (longFlag) {
num = va_arg(ap, long int);
} else {
num = va_arg(ap, int);
}
length = PrintNum(buf, num, 8, 0, width, ladjust, padc, 0);
OUTPUT(arg, buf, length);
break;
case 'u':
case 'U':
if (longFlag) {
num = va_arg(ap, long int);
} else {
num = va_arg(ap, int);
}
length = PrintNum(buf, num, 10, 0, width, ladjust, padc, 0);
OUTPUT(arg, buf, length);
break;
case 'x':
if (longFlag) {
num = va_arg(ap, long int);
} else {
num = va_arg(ap, int);
}
length = PrintNum(buf, num, 16, 0, width, ladjust, padc, 0);
OUTPUT(arg, buf, length);
break;
case 'X':
if (longFlag) {
num = va_arg(ap, long int);
} else {
num = va_arg(ap, int);
}
length = PrintNum(buf, num, 16, 0, width, ladjust, padc, 1);
OUTPUT(arg, buf, length);
break;
case 'c':
c = (char)va_arg(ap, int);
length = PrintChar(buf, c, width, ladjust);
OUTPUT(arg, buf, length);
break;
case 's':
s = (char*)va_arg(ap, char *);
length = PrintString(buf, s, width, ladjust);
OUTPUT(arg, buf, length);
break;
case '\0':
fmt --;
break;
default:
/* output this char as it is */
OUTPUT(arg, fmt, 1);
} /* switch (*fmt) */
fmt ++;
} /* for(;;) */
/* special termination call */
OUTPUT(arg, "\0", 1);
}
/* --------------- local help functions --------------------- */
int
PrintChar(char * buf, char c, int length, int ladjust)
{
int i;
if (length < 1) length = 1;
if (ladjust) {
*buf = c;
for (i=1; i< length; i++) buf[i] = ' ';
} else {
for (i=0; i< length-1; i++) buf[i] = ' ';
buf[length - 1] = c;
}
return length;
}
int
PrintString(char * buf, char* s, int length, int ladjust)
{
int i;
int len=0;
char* s1 = s;
while (*s1++) len++;
if (length < len) length = len;
if (ladjust) {
for (i=0; i< len; i++) buf[i] = s[i];
for (i=len; i< length; i++) buf[i] = ' ';
} else {
for (i=0; i< length-len; i++) buf[i] = ' ';
for (i=length-len; i < length; i++) buf[i] = s[i-length+len];
}
return length;
}
int
PrintNum(char * buf, unsigned long u, int base, int negFlag,
int length, int ladjust, char padc, int upcase)
{
/* algorithm :
* 1. prints the number from left to right in reverse form.
* 2. fill the remaining spaces with padc if length is longer than
* the actual length
* TRICKY : if left adjusted, no "0" padding.
* if negtive, insert "0" padding between "0" and number.
* 3. if (!ladjust) we reverse the whole string including paddings
* 4. otherwise we only reverse the actual string representing the num.
*/
int actualLength =0;
char *p = buf;
int i;
do {
int tmp = u %base;
if (tmp <= 9) {
*p++ = '0' + tmp;
} else if (upcase) {
*p++ = 'A' + tmp - 10;
} else {
*p++ = 'a' + tmp - 10;
}
u /= base;
} while (u != 0);
if (negFlag) {
*p++ = '-';
}
/* figure out actual length and adjust the maximum length */
actualLength = p - buf;
if (length < actualLength) length = actualLength;
/* add padding */
if (ladjust) {
padc = ' ';
}
if (negFlag && !ladjust && (padc == '0')) {
for (i = actualLength-1; i< length-1; i++) buf[i] = padc;
buf[length -1] = '-';
} else {
for (i = actualLength; i< length; i++) buf[i] = padc;
}
/* prepare to reverse the string */
{
int begin = 0;
int end;
if (ladjust) {
end = actualLength - 1;
} else {
end = length -1;
}
while (end > begin) {
char tmp = buf[begin];
buf[begin] = buf[end];
buf[end] = tmp;
begin ++;
end --;
}
}
/* adjust the string pointer */
return length;
}
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