mirror of
https://github.com/cc65/cc65.git
synced 2024-12-23 04:30:10 +00:00
163c4e2fc8
git-svn-id: svn://svn.cc65.org/cc65/trunk@3312 b7a2c559-68d2-44c3-8de9-860c34a00d81
687 lines
18 KiB
C
687 lines
18 KiB
C
/*
|
|
* _scanf.c
|
|
*
|
|
* (C) Copyright 2001-2002 Ullrich von Bassewitz (uz@cc65.org)
|
|
*
|
|
* This is the basic layer for all scanf type functions. It should get
|
|
* rewritten in assembler at some time in the future, so most of the code
|
|
* is not as elegant as it could be.
|
|
*/
|
|
|
|
|
|
|
|
#include <stdio.h>
|
|
#include <stdarg.h>
|
|
#include <stddef.h>
|
|
#include <string.h>
|
|
#include <setjmp.h>
|
|
#include <ctype.h>
|
|
#include <limits.h>
|
|
|
|
#include "_scanf.h"
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* SetJmp return codes */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
#define RC_OK 0 /* Regular call */
|
|
#define RC_EOF 1 /* EOF reached */
|
|
#define RC_NOCONV 2 /* No conversion possible */
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* Data */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
static struct scanfdata* D_; /* Copy of function argument */
|
|
static va_list ap; /* Copy of function argument */
|
|
static jmp_buf JumpBuf; /* Label that is used in case of EOF */
|
|
static unsigned CharCount; /* Characters read so far */
|
|
static int C; /* Character from input */
|
|
static unsigned Width; /* Maximum field width */
|
|
static long IntVal; /* Converted int value */
|
|
static unsigned Conversions; /* Number of conversions */
|
|
static unsigned char IntBytes; /* Number of bytes-1 for int conversions */
|
|
|
|
/* Flags */
|
|
static unsigned char Positive; /* Flag for positive value */
|
|
static unsigned char NoAssign; /* Supppress assigment */
|
|
static unsigned char Invert; /* Do we need to invert the charset? */
|
|
static unsigned char CharSet[32]; /* 32 * 8 bits = 256 bits */
|
|
static const unsigned char Bits[8] = {
|
|
0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80
|
|
};
|
|
|
|
/* We need C to be 16 bits since we cannot check for EOF otherwise.
|
|
* Unfortunately, this causes the code to be quite larger, even if for most
|
|
* purposes, checking the low byte would be enough, since if C is EOF, the
|
|
* low byte will not match any useful character anyway (at least for the
|
|
* supported platforms - I know that this is not portable). So the following
|
|
* macro is used to access just the low byte of C.
|
|
*/
|
|
#define CHAR(c) (*((unsigned char*)&(c)))
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* Character sets */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
static void __fastcall__ AddCharToSet (unsigned char C)
|
|
/* Set the given bit in the character set */
|
|
{
|
|
asm ("ldy #%o", C);
|
|
asm ("lda (sp),y");
|
|
asm ("lsr a");
|
|
asm ("lsr a");
|
|
asm ("lsr a");
|
|
asm ("tax");
|
|
asm ("lda (sp),y");
|
|
asm ("and #$07");
|
|
asm ("tay");
|
|
asm ("lda %v,y", Bits);
|
|
asm ("ora %v,x", CharSet);
|
|
asm ("sta %v,x", CharSet);
|
|
}
|
|
|
|
|
|
|
|
static unsigned char __fastcall__ IsCharInSet (unsigned char C)
|
|
/* Check if the given char is part of the character set */
|
|
{
|
|
asm ("ldy #%o", C);
|
|
asm ("lda (sp),y");
|
|
asm ("lsr a");
|
|
asm ("lsr a");
|
|
asm ("lsr a");
|
|
asm ("tax");
|
|
asm ("lda (sp),y");
|
|
asm ("and #$07");
|
|
asm ("tay");
|
|
asm ("lda %v,y", Bits);
|
|
asm ("and %v,x", CharSet);
|
|
asm ("ldx #$00");
|
|
return __AX__;
|
|
}
|
|
|
|
|
|
|
|
static void InvertCharSet (void)
|
|
/* Invert the character set */
|
|
{
|
|
asm ("ldy #%b", sizeof (CharSet) - 1);
|
|
asm ("L1:");
|
|
asm ("lda %v,y", CharSet);
|
|
asm ("eor #$FF");
|
|
asm ("sta %v,y", CharSet);
|
|
asm ("dey");
|
|
asm ("bpl L1");
|
|
}
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* Code */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
static void __fastcall__ Error (unsigned char Code)
|
|
/* Does a longjmp using the given code */
|
|
{
|
|
longjmp (JumpBuf, Code);
|
|
}
|
|
|
|
|
|
|
|
static void ReadChar (void)
|
|
/* Get an input character, count characters */
|
|
{
|
|
/* Move D to ptr1 */
|
|
asm ("lda %v", D_);
|
|
asm ("ldx %v+1", D_);
|
|
asm ("sta ptr1");
|
|
asm ("stx ptr1+1");
|
|
|
|
/* Copy the get vector to jmpvec */
|
|
asm ("ldy #%b", offsetof (struct scanfdata, get));
|
|
asm ("lda (ptr1),y");
|
|
asm ("sta jmpvec+1");
|
|
asm ("iny");
|
|
asm ("lda (ptr1),y");
|
|
asm ("sta jmpvec+2");
|
|
|
|
/* Load D->data into __AX__ */
|
|
asm ("ldy #%b", offsetof (struct scanfdata, data)+1);
|
|
asm ("lda (ptr1),y");
|
|
asm ("tax");
|
|
asm ("dey");
|
|
asm ("lda (ptr1),y");
|
|
|
|
/* Call the get routine */
|
|
asm ("jsr jmpvec");
|
|
|
|
/* Assign the result to C */
|
|
asm ("sta %v", C);
|
|
asm ("stx %v+1", C);
|
|
|
|
/* If C is not EOF, bump the character counter. */
|
|
asm ("inx");
|
|
asm ("bne %g", Done);
|
|
asm ("cmp #$FF");
|
|
asm ("bne %g", Done);
|
|
|
|
/* Must bump CharCount. */
|
|
asm ("inc %v", CharCount);
|
|
asm ("bne %g", Done);
|
|
asm ("inc %v+1", CharCount);
|
|
|
|
Done:
|
|
}
|
|
|
|
|
|
|
|
static void ReadCharWithCheck (void)
|
|
/* Get an input char, use longjmp in case of EOF */
|
|
{
|
|
ReadChar ();
|
|
if (C == EOF) {
|
|
Error (RC_EOF);
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void SkipWhite (void)
|
|
/* Skip white space in the input and return the first non white character */
|
|
{
|
|
while (isspace (C)) {
|
|
ReadChar ();
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void ReadSign (void)
|
|
/* Read an optional sign and skip it. Store 1 in Positive if the value is
|
|
* positive, store 0 otherwise.
|
|
*/
|
|
{
|
|
/* We can ignore the high byte of C here, since if it is EOF, the lower
|
|
* byte won't match anyway.
|
|
*/
|
|
asm ("lda %v", C);
|
|
asm ("cmp #'-'");
|
|
asm ("bne %g", NotNeg);
|
|
|
|
/* Negative value */
|
|
asm ("jsr %v", ReadChar);
|
|
asm ("lda #$00"); /* Flag as negative */
|
|
asm ("beq %g", Store);
|
|
|
|
/* Positive value */
|
|
NotNeg:
|
|
asm ("cmp #'+'");
|
|
asm ("bne %g", Pos);
|
|
asm ("jsr %v", ReadChar); /* Skip the + sign */
|
|
Pos:
|
|
asm ("lda #$01"); /* Flag as positive */
|
|
Store:
|
|
asm ("sta %v", Positive);
|
|
}
|
|
|
|
|
|
|
|
static unsigned char HexVal (char C)
|
|
/* Convert a digit to a value */
|
|
{
|
|
|
|
if (isdigit (C)) {
|
|
return C - '0';
|
|
} else {
|
|
return toupper (C) - ('A' - 10);
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void AssignInt (void)
|
|
/* Assign the integer value in Val to the next argument. The function makes
|
|
* several non portable assumptions to reduce code size:
|
|
* - int and unsigned types have the same representation
|
|
* - short and int have the same representation.
|
|
* - all pointer types have the same representation.
|
|
*/
|
|
{
|
|
if (!NoAssign) {
|
|
|
|
/* Get the next argument pointer */
|
|
__AX__ = (unsigned) va_arg (ap, void*);
|
|
|
|
/* Store the argument pointer into ptr1 */
|
|
asm ("sta ptr1");
|
|
asm ("stx ptr1+1");
|
|
|
|
/* Get the number of bytes-1 to copy */
|
|
asm ("ldy %v", IntBytes);
|
|
|
|
/* Assign the integer value */
|
|
Loop: asm ("lda %v,y", IntVal);
|
|
asm ("sta (ptr1),y");
|
|
asm ("dey");
|
|
asm ("bpl %g", Loop);
|
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static unsigned char ReadInt (unsigned char Base)
|
|
/* Read an integer and store it into IntVal. Returns the number of chars
|
|
* converted. Does NOT bump Conversions.
|
|
*/
|
|
{
|
|
unsigned char Val;
|
|
unsigned char CharCount = 0;
|
|
|
|
/* Read the integer value */
|
|
IntVal = 0;
|
|
while (isxdigit (C) && Width-- > 0 && (Val = HexVal (C)) < Base) {
|
|
++CharCount;
|
|
IntVal = IntVal * Base + Val;
|
|
ReadChar ();
|
|
}
|
|
|
|
/* If we didn't convert anything, it's an error */
|
|
if (CharCount == 0) {
|
|
Error (RC_NOCONV);
|
|
}
|
|
|
|
/* Return the number of characters converted */
|
|
return CharCount;
|
|
}
|
|
|
|
|
|
|
|
static void __fastcall__ ScanInt (unsigned char Base)
|
|
/* Scan an integer including white space, sign and optional base spec,
|
|
* and store it into IntVal.
|
|
*/
|
|
{
|
|
/* Skip whitespace */
|
|
SkipWhite ();
|
|
|
|
/* Read an optional sign */
|
|
ReadSign ();
|
|
|
|
/* If Base is unknown (zero), figure it out */
|
|
if (Base == 0) {
|
|
if (CHAR (C) == '0') {
|
|
ReadChar ();
|
|
switch (CHAR (C)) {
|
|
case 'x':
|
|
case 'X':
|
|
Base = 16;
|
|
ReadChar ();
|
|
break;
|
|
default:
|
|
Base = 8;
|
|
}
|
|
} else {
|
|
Base = 10;
|
|
}
|
|
}
|
|
|
|
/* Read the integer value */
|
|
ReadInt (Base);
|
|
|
|
/* Apply the sign */
|
|
if (!Positive) {
|
|
IntVal = -IntVal;
|
|
}
|
|
|
|
/* Assign the value to the next argument unless suppressed */
|
|
AssignInt ();
|
|
|
|
/* One more conversion */
|
|
++Conversions;
|
|
}
|
|
|
|
|
|
|
|
int __fastcall__ _scanf (register struct scanfdata* D,
|
|
register const char* format, va_list ap_)
|
|
/* This is the routine used to do the actual work. It is called from several
|
|
* types of wrappers to implement the actual ISO xxscanf functions.
|
|
*/
|
|
{
|
|
register char F; /* Character from format string */
|
|
unsigned char Result; /* setjmp result */
|
|
char* S;
|
|
unsigned char HaveWidth; /* True if a width was given */
|
|
char Start; /* Start of range */
|
|
|
|
/* Place copies of the arguments into global variables. This is not very
|
|
* nice, but on a 6502 platform it gives better code, since the values
|
|
* do not have to be passed as parameters.
|
|
*/
|
|
D_ = D;
|
|
ap = ap_;
|
|
|
|
/* Initialize variables */
|
|
Conversions = 0;
|
|
CharCount = 0;
|
|
|
|
/* Set up the jump label. The get() routine will use this label when EOF
|
|
* is reached.
|
|
*/
|
|
Result = setjmp (JumpBuf);
|
|
if (Result == RC_OK) {
|
|
|
|
Again:
|
|
/* Get the next input character */
|
|
ReadChar ();
|
|
|
|
/* Walk over the format string */
|
|
while (F = *format++) {
|
|
|
|
/* Check for a conversion */
|
|
if (F != '%' || *format == '%') {
|
|
|
|
/* %% or any char other than % */
|
|
if (F == '%') {
|
|
++format;
|
|
}
|
|
|
|
/* Check for a match */
|
|
if (isspace (F)) {
|
|
|
|
/* Special white space handling: Any whitespace in the
|
|
* format string matches any amount of whitespace including
|
|
* none(!). So this match will never fail.
|
|
*/
|
|
SkipWhite ();
|
|
continue;
|
|
|
|
} else if (F == C) {
|
|
|
|
/* A match. Read the next input character and start over */
|
|
goto Again;
|
|
|
|
} else {
|
|
|
|
/* A mismatch. We will stop scanning the input and return
|
|
* the number of conversions.
|
|
*/
|
|
return Conversions;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
/* A conversion. Skip the percent sign. */
|
|
F = *format++;
|
|
|
|
/* 1. Assignment suppression */
|
|
if (F == '*') {
|
|
F = *format++;
|
|
NoAssign = 1;
|
|
} else {
|
|
NoAssign = 0;
|
|
}
|
|
|
|
/* 2. Maximum field width */
|
|
Width = UINT_MAX;
|
|
HaveWidth = 0;
|
|
if (isdigit (F)) {
|
|
HaveWidth = 1;
|
|
Width = 0;
|
|
do {
|
|
/* ### Non portable ### */
|
|
Width = Width * 10 + (F & 0x0F);
|
|
F = *format++;
|
|
} while (isdigit (F));
|
|
}
|
|
|
|
/* 3. Length modifier */
|
|
IntBytes = sizeof(int) - 1;
|
|
switch (F) {
|
|
case 'h':
|
|
if (*format == 'h') {
|
|
IntBytes = sizeof(char) - 1;
|
|
++format;
|
|
}
|
|
F = *format++;
|
|
break;
|
|
|
|
case 'l':
|
|
if (*format == 'l') {
|
|
/* Treat long long as long */
|
|
++format;
|
|
}
|
|
/* FALLTHROUGH */
|
|
case 'j': /* intmax_t */
|
|
IntBytes = sizeof(long) - 1;
|
|
F = *format++;
|
|
break;
|
|
|
|
case 'z': /* size_t */
|
|
case 't': /* ptrdiff_t */
|
|
case 'L': /* long double - ignore this one */
|
|
F = *format++;
|
|
break;
|
|
}
|
|
|
|
/* 4. Conversion specifier */
|
|
switch (F) {
|
|
|
|
/* 'd' and 'u' conversions are actually the same, since the
|
|
* standard says that evene the 'u' modifier allows an
|
|
* optionally signed integer.
|
|
*/
|
|
case 'd': /* Optionally signed decimal integer */
|
|
case 'u':
|
|
ScanInt (10);
|
|
break;
|
|
|
|
case 'i':
|
|
/* Optionally signed integer with a base */
|
|
ScanInt (0);
|
|
break;
|
|
|
|
case 'o':
|
|
/* Optionally signed octal integer */
|
|
ScanInt (8);
|
|
break;
|
|
|
|
case 'x':
|
|
case 'X':
|
|
/* Optionally signed hexadecimal integer */
|
|
ScanInt (16);
|
|
break;
|
|
|
|
case 'E':
|
|
case 'e':
|
|
case 'f':
|
|
case 'g':
|
|
/* Optionally signed float */
|
|
Error (RC_NOCONV);
|
|
break;
|
|
|
|
case 's':
|
|
/* Whitespace terminated string */
|
|
SkipWhite ();
|
|
if (!NoAssign) {
|
|
S = va_arg (ap, char*);
|
|
}
|
|
while (!isspace (C) && Width--) {
|
|
if (!NoAssign) {
|
|
*S++ = C;
|
|
}
|
|
ReadChar ();
|
|
}
|
|
/* Terminate the string just read */
|
|
if (!NoAssign) {
|
|
*S = '\0';
|
|
}
|
|
++Conversions;
|
|
break;
|
|
|
|
case 'c':
|
|
/* Fixed length string, NOT zero terminated */
|
|
if (!HaveWidth) {
|
|
/* No width given, default is 1 */
|
|
Width = 1;
|
|
}
|
|
if (!NoAssign) {
|
|
S = va_arg (ap, char*);
|
|
while (Width--) {
|
|
*S++ = C;
|
|
ReadCharWithCheck ();
|
|
}
|
|
} else {
|
|
/* Just skip as many chars as given */
|
|
while (Width--) {
|
|
ReadCharWithCheck ();
|
|
}
|
|
}
|
|
++Conversions;
|
|
break;
|
|
|
|
case '[':
|
|
/* String using characters from a set */
|
|
Invert = 0;
|
|
/* Clear the set */
|
|
memset (CharSet, 0, sizeof (CharSet));
|
|
F = *format++;
|
|
if (F == '^') {
|
|
Invert = 1;
|
|
F = *format++;
|
|
}
|
|
if (F == ']') {
|
|
AddCharToSet (']');
|
|
F = *format++;
|
|
}
|
|
/* Read the characters that are part of the set */
|
|
while (F != ']' && F != '\0') {
|
|
if (*format == '-') {
|
|
/* A range. Get start and end, skip the '-' */
|
|
Start = F;
|
|
F = *++format;
|
|
++format;
|
|
if (F == ']') {
|
|
/* '-' as last char means: include '-' */
|
|
AddCharToSet (Start);
|
|
AddCharToSet ('-');
|
|
} else if (F != '\0') {
|
|
/* Include all chars in the range */
|
|
while (1) {
|
|
AddCharToSet (Start);
|
|
if (Start == F) {
|
|
break;
|
|
}
|
|
++Start;
|
|
}
|
|
/* Get next char after range */
|
|
F = *format++;
|
|
}
|
|
} else {
|
|
/* Just a character */
|
|
AddCharToSet (F);
|
|
/* Get next char */
|
|
F = *format++;
|
|
}
|
|
}
|
|
|
|
/* Invert the set if requested */
|
|
if (Invert) {
|
|
InvertCharSet ();
|
|
}
|
|
|
|
/* We have the set in CharSet. Read characters and
|
|
* store them into a string while they are part of
|
|
* the set.
|
|
*/
|
|
if (!NoAssign) {
|
|
S = va_arg (ap, char*);
|
|
while (IsCharInSet (C) && Width--) {
|
|
*S++ = C;
|
|
ReadChar ();
|
|
}
|
|
*S = '\0';
|
|
} else {
|
|
while (IsCharInSet (C) && Width--) {
|
|
ReadChar ();
|
|
}
|
|
}
|
|
++Conversions;
|
|
break;
|
|
|
|
case 'p':
|
|
/* Pointer, format is 0xABCD */
|
|
SkipWhite ();
|
|
if (CHAR (C) != '0') {
|
|
Error (RC_NOCONV);
|
|
}
|
|
ReadChar ();
|
|
if (CHAR (C) != 'x' && CHAR (C) != 'X') {
|
|
Error (RC_NOCONV);
|
|
}
|
|
ReadChar ();
|
|
if (ReadInt (16) != 4) { /* 4 chars expected */
|
|
Error (RC_NOCONV);
|
|
}
|
|
AssignInt ();
|
|
++Conversions;
|
|
break;
|
|
|
|
case 'n':
|
|
/* Store characters consumed so far */
|
|
IntVal = CharCount;
|
|
AssignInt ();
|
|
break;
|
|
|
|
default:
|
|
/* Invalid conversion */
|
|
Error (RC_NOCONV);
|
|
break;
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Push back the last unused character, provided it is not EOF */
|
|
if (C != EOF) {
|
|
D->unget (C, D->data);
|
|
}
|
|
|
|
} else {
|
|
|
|
/* Jump via JumpBuf means an error. If this happens at EOF with no
|
|
* conversions, it is considered an error, otherwise the number
|
|
* of conversions is returned (the default behaviour).
|
|
*/
|
|
if (C == EOF && CharCount == 0) {
|
|
/* Special case: error */
|
|
Conversions = EOF;
|
|
}
|
|
|
|
}
|
|
|
|
/* Return the number of conversions */
|
|
return Conversions;
|
|
}
|
|
|
|
|
|
|
|
|