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util.c
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util.c
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/**********************************************************************
util.c -
$Author$
$Date$
created at: Fri Mar 10 17:22:34 JST 1995
Copyright (C) 1993-2003 Yukihiro Matsumoto
**********************************************************************/
#include "ruby.h"
#include <ctype.h>
#include <stdio.h>
#include <errno.h>
#ifdef _WIN32
#include "missing/file.h"
#endif
#include "util.h"
#ifndef HAVE_STRING_H
char *strchr _((char*,char));
#endif
unsigned long
scan_oct(start, len, retlen)
const char *start;
int len;
int *retlen;
{
register const char *s = start;
register unsigned long retval = 0;
while (len-- && *s >= '0' && *s <= '7') {
retval <<= 3;
retval |= *s++ - '0';
}
*retlen = s - start;
return retval;
}
unsigned long
scan_hex(start, len, retlen)
const char *start;
int len;
int *retlen;
{
static char hexdigit[] = "0123456789abcdef0123456789ABCDEF";
register const char *s = start;
register unsigned long retval = 0;
char *tmp;
while (len-- && *s && (tmp = strchr(hexdigit, *s))) {
retval <<= 4;
retval |= (tmp - hexdigit) & 15;
s++;
}
*retlen = s - start;
return retval;
}
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#if defined(HAVE_FCNTL_H)
#include <fcntl.h>
#endif
#ifndef S_ISDIR
# define S_ISDIR(m) ((m & S_IFMT) == S_IFDIR)
#endif
#ifdef _WIN32
#include "missing/file.h"
#endif
#if defined(MSDOS) || defined(__CYGWIN32__) || defined(_WIN32)
/*
* Copyright (c) 1993, Intergraph Corporation
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the perl README file.
*
* Various Unix compatibility functions and NT specific functions.
*
* Some of this code was derived from the MSDOS port(s) and the OS/2 port.
*
*/
/*
* Suffix appending for in-place editing under MS-DOS and OS/2 (and now NT!).
*
* Here are the rules:
*
* Style 0: Append the suffix exactly as standard perl would do it.
* If the filesystem groks it, use it. (HPFS will always
* grok it. So will NTFS. FAT will rarely accept it.)
*
* Style 1: The suffix begins with a '.'. The extension is replaced.
* If the name matches the original name, use the fallback method.
*
* Style 2: The suffix is a single character, not a '.'. Try to add the
* suffix to the following places, using the first one that works.
* [1] Append to extension.
* [2] Append to filename,
* [3] Replace end of extension,
* [4] Replace end of filename.
* If the name matches the original name, use the fallback method.
*
* Style 3: Any other case: Ignore the suffix completely and use the
* fallback method.
*
* Fallback method: Change the extension to ".$$$". If that matches the
* original name, then change the extension to ".~~~".
*
* If filename is more than 1000 characters long, we die a horrible
* death. Sorry.
*
* The filename restriction is a cheat so that we can use buf[] to store
* assorted temporary goo.
*
* Examples, assuming style 0 failed.
*
* suffix = ".bak" (style 1)
* foo.bar => foo.bak
* foo.bak => foo.$$$ (fallback)
* foo.$$$ => foo.~~~ (fallback)
* makefile => makefile.bak
*
* suffix = "~" (style 2)
* foo.c => foo.c~
* foo.c~ => foo.c~~
* foo.c~~ => foo~.c~~
* foo~.c~~ => foo~~.c~~
* foo~~~~~.c~~ => foo~~~~~.$$$ (fallback)
*
* foo.pas => foo~.pas
* makefile => makefile.~
* longname.fil => longname.fi~
* longname.fi~ => longnam~.fi~
* longnam~.fi~ => longnam~.$$$
*
*/
static int valid_filename(char *s);
static char suffix1[] = ".$$$";
static char suffix2[] = ".~~~";
#define ext (&buf[1000])
#define strEQ(s1,s2) (strcmp(s1,s2) == 0)
void
ruby_add_suffix(str, suffix)
VALUE str;
char *suffix;
{
int baselen;
int extlen = strlen(suffix);
char *s, *t, *p;
long slen;
char buf[1024];
if (RSTRING(str)->len > 1000)
rb_fatal("Cannot do inplace edit on long filename (%ld characters)",
RSTRING(str)->len);
#if defined(DJGPP) || defined(__CYGWIN32__) || defined(_WIN32)
/* Style 0 */
slen = RSTRING(str)->len;
rb_str_cat(str, suffix, extlen);
#if defined(DJGPP)
if (_USE_LFN) return;
#else
if (valid_filename(RSTRING(str)->ptr)) return;
#endif
/* Fooey, style 0 failed. Fix str before continuing. */
RSTRING(str)->ptr[RSTRING(str)->len = slen] = '\0';
#endif
slen = extlen;
t = buf; baselen = 0; s = RSTRING(str)->ptr;
while ((*t = *s) && *s != '.') {
baselen++;
if (*s == '\\' || *s == '/') baselen = 0;
s++; t++;
}
p = t;
t = ext; extlen = 0;
while (*t++ = *s++) extlen++;
if (extlen == 0) { ext[0] = '.'; ext[1] = 0; extlen++; }
if (*suffix == '.') { /* Style 1 */
if (strEQ(ext, suffix)) goto fallback;
strcpy(p, suffix);
}
else if (suffix[1] == '\0') { /* Style 2 */
if (extlen < 4) {
ext[extlen] = *suffix;
ext[++extlen] = '\0';
}
else if (baselen < 8) {
*p++ = *suffix;
}
else if (ext[3] != *suffix) {
ext[3] = *suffix;
}
else if (buf[7] != *suffix) {
buf[7] = *suffix;
}
else goto fallback;
strcpy(p, ext);
}
else { /* Style 3: Panic */
fallback:
(void)memcpy(p, strEQ(ext, suffix1) ? suffix2 : suffix1, 5);
}
rb_str_resize(str, strlen(buf));
memcpy(RSTRING(str)->ptr, buf, RSTRING(str)->len);
}
#if defined(__CYGWIN32__) || defined(_WIN32)
static int
valid_filename(char *s)
{
int fd;
/*
// if the file exists, then it's a valid filename!
*/
if (_access(s, 0) == 0) {
return 1;
}
/*
// It doesn't exist, so see if we can open it.
*/
if ((fd = _open(s, O_CREAT, 0666)) >= 0) {
_close(fd);
_unlink (s); /* don't leave it laying around */
return 1;
}
return 0;
}
#endif
#endif
#if defined __DJGPP__
#include <dpmi.h>
static char dbcs_table[256];
int
make_dbcs_table()
{
__dpmi_regs r;
struct {
unsigned char start;
unsigned char end;
} vec;
int offset;
memset(&r, 0, sizeof(r));
r.x.ax = 0x6300;
__dpmi_int(0x21, &r);
offset = r.x.ds * 16 + r.x.si;
for (;;) {
int i;
dosmemget(offset, sizeof vec, &vec);
if (!vec.start && !vec.end)
break;
for (i = vec.start; i <= vec.end; i++)
dbcs_table[i] = 1;
offset += 2;
}
}
int
mblen(const char *s, size_t n)
{
static int need_init = 1;
if (need_init) {
make_dbcs_table();
need_init = 0;
}
if (s) {
if (n == 0 || *s == 0)
return 0;
return dbcs_table[(unsigned char)*s] + 1;
}
else
return 1;
}
struct PathList {
struct PathList *next;
char *path;
};
struct PathInfo {
struct PathList *head;
int count;
};
static void
push_element(const char *path, VALUE vinfo)
{
struct PathList *p;
struct PathInfo *info = (struct PathInfo *)vinfo;
p = ALLOC(struct PathList);
MEMZERO(p, struct PathList, 1);
p->path = ruby_strdup(path);
p->next = info->head;
info->head = p;
info->count++;
}
#include <dirent.h>
int __opendir_flags = __OPENDIR_PRESERVE_CASE;
char **
__crt0_glob_function(char *path)
{
int len = strlen(path);
int i;
char **rv;
char path_buffer[PATH_MAX];
char *buf = path_buffer;
char *p;
struct PathInfo info;
struct PathList *plist;
if (PATH_MAX <= len)
buf = ruby_xmalloc(len + 1);
strncpy(buf, path, len);
buf[len] = '\0';
for (p = buf; *p; p += mblen(p, MB_CUR_MAX))
if (*p == '\\')
*p = '/';
info.count = 0;
info.head = 0;
rb_globi(buf, push_element, (VALUE)&info);
if (buf != path_buffer)
ruby_xfree(buf);
if (info.count == 0)
return 0;
rv = ruby_xmalloc((info.count + 1) * sizeof (char *));
plist = info.head;
i = 0;
while (plist) {
struct PathList *cur;
rv[i] = plist->path;
cur = plist;
plist = plist->next;
ruby_xfree(cur);
i++;
}
rv[i] = 0;
return rv;
}
#endif
/* mm.c */
#define A ((int*)a)
#define B ((int*)b)
#define C ((int*)c)
#define D ((int*)d)
#define mmprepare(base, size) do {\
if (((long)base & (0x3)) == 0)\
if (size >= 16) mmkind = 1;\
else mmkind = 0;\
else mmkind = -1;\
high = (size & (~0xf));\
low = (size & 0x0c);\
} while (0)\
#define mmarg mmkind, size, high, low
static void mmswap_(a, b, mmarg)
register char *a, *b;
int mmarg;
{
register int s;
if (a == b) return;
if (mmkind >= 0) {
if (mmkind > 0) {
register char *t = a + high;
do {
s = A[0]; A[0] = B[0]; B[0] = s;
s = A[1]; A[1] = B[1]; B[1] = s;
s = A[2]; A[2] = B[2]; B[2] = s;
s = A[3]; A[3] = B[3]; B[3] = s; a += 16; b += 16;
} while (a < t);
}
if (low != 0) { s = A[0]; A[0] = B[0]; B[0] = s;
if (low >= 8) { s = A[1]; A[1] = B[1]; B[1] = s;
if (low == 12) {s = A[2]; A[2] = B[2]; B[2] = s;}}}
}
else {
register char *t = a + size;
do {s = *a; *a++ = *b; *b++ = s;} while (a < t);
}
}
#define mmswap(a,b) mmswap_((a),(b),mmarg)
static void mmrot3_(a, b, c, mmarg)
register char *a, *b, *c;
int mmarg;
{
register int s;
if (mmkind >= 0) {
if (mmkind > 0) {
register char *t = a + high;
do {
s = A[0]; A[0] = B[0]; B[0] = C[0]; C[0] = s;
s = A[1]; A[1] = B[1]; B[1] = C[1]; C[1] = s;
s = A[2]; A[2] = B[2]; B[2] = C[2]; C[2] = s;
s = A[3]; A[3] = B[3]; B[3] = C[3]; C[3] = s; a += 16; b += 16; c += 16;
} while (a < t);
}
if (low != 0) { s = A[0]; A[0] = B[0]; B[0] = C[0]; C[0] = s;
if (low >= 8) { s = A[1]; A[1] = B[1]; B[1] = C[1]; C[1] = s;
if (low == 12) {s = A[2]; A[2] = B[2]; B[2] = C[2]; C[2] = s;}}}
}
else {
register char *t = a + size;
do {s = *a; *a++ = *b; *b++ = *c; *c++ = s;} while (a < t);
}
}
#define mmrot3(a,b,c) mmrot3_((a),(b),(c),mmarg)
/* qs6.c */
/*****************************************************/
/* */
/* qs6 (Quick sort function) */
/* */
/* by Tomoyuki Kawamura 1995.4.21 */
/* [email protected] */
/*****************************************************/
typedef struct { char *LL, *RR; } stack_node; /* Stack structure for L,l,R,r */
#define PUSH(ll,rr) do { top->LL = (ll); top->RR = (rr); ++top; } while (0) /* Push L,l,R,r */
#define POP(ll,rr) do { --top; ll = top->LL; rr = top->RR; } while (0) /* Pop L,l,R,r */
#define med3(a,b,c) ((*cmp)(a,b)<0 ? \
((*cmp)(b,c)<0 ? b : ((*cmp)(a,c)<0 ? c : a)) : \
((*cmp)(b,c)>0 ? b : ((*cmp)(a,c)<0 ? a : c)))
void ruby_qsort (base, nel, size, cmp)
void* base;
const int nel;
const int size;
int (*cmp)();
{
register char *l, *r, *m; /* l,r:left,right group m:median point */
register int t, eq_l, eq_r; /* eq_l: all items in left group are equal to S */
char *L = base; /* left end of curren region */
char *R = (char*)base + size*(nel-1); /* right end of current region */
int chklim = 63; /* threshold of ordering element check */
stack_node stack[32], *top = stack; /* 32 is enough for 32bit CPU */
int mmkind, high, low;
if (nel <= 1) return; /* need not to sort */
mmprepare(base, size);
goto start;
nxt:
if (stack == top) return; /* return if stack is empty */
POP(L,R);
for (;;) {
start:
if (L + size == R) { /* 2 elements */
if ((*cmp)(L,R) > 0) mmswap(L,R); goto nxt;
}
l = L; r = R;
t = (r - l + size) / size; /* number of elements */
m = l + size * (t >> 1); /* calculate median value */
if (t >= 60) {
register char *m1;
register char *m3;
if (t >= 200) {
t = size*(t>>3); /* number of bytes in splitting 8 */
{
register char *p1 = l + t;
register char *p2 = p1 + t;
register char *p3 = p2 + t;
m1 = med3(p1, p2, p3);
p1 = m + t;
p2 = p1 + t;
p3 = p2 + t;
m3 = med3(p1, p2, p3);
}
}
else {
t = size*(t>>2); /* number of bytes in splitting 4 */
m1 = l + t;
m3 = m + t;
}
m = med3(m1, m, m3);
}
if ((t = (*cmp)(l,m)) < 0) { /*3-5-?*/
if ((t = (*cmp)(m,r)) < 0) { /*3-5-7*/
if (chklim && nel >= chklim) { /* check if already ascending order */
char *p;
chklim = 0;
for (p=l; p<r; p+=size) if ((*cmp)(p,p+size) > 0) goto fail;
goto nxt;
}
fail: goto loopA; /*3-5-7*/
}
if (t > 0) {
if ((*cmp)(l,r) <= 0) {mmswap(m,r); goto loopA;} /*3-5-4*/
mmrot3(r,m,l); goto loopA; /*3-5-2*/
}
goto loopB; /*3-5-5*/
}
if (t > 0) { /*7-5-?*/
if ((t = (*cmp)(m,r)) > 0) { /*7-5-3*/
if (chklim && nel >= chklim) { /* check if already ascending order */
char *p;
chklim = 0;
for (p=l; p<r; p+=size) if ((*cmp)(p,p+size) < 0) goto fail2;
while (l<r) {mmswap(l,r); l+=size; r-=size;} /* reverse region */
goto nxt;
}
fail2: mmswap(l,r); goto loopA; /*7-5-3*/
}
if (t < 0) {
if ((*cmp)(l,r) <= 0) {mmswap(l,m); goto loopB;} /*7-5-8*/
mmrot3(l,m,r); goto loopA; /*7-5-6*/
}
mmswap(l,r); goto loopA; /*7-5-5*/
}
if ((t = (*cmp)(m,r)) < 0) {goto loopA;} /*5-5-7*/
if (t > 0) {mmswap(l,r); goto loopB;} /*5-5-3*/
/* determining splitting type in case 5-5-5 */ /*5-5-5*/
for (;;) {
if ((l += size) == r) goto nxt; /*5-5-5*/
if (l == m) continue;
if ((t = (*cmp)(l,m)) > 0) {mmswap(l,r); l = L; goto loopA;} /*575-5*/
if (t < 0) {mmswap(L,l); l = L; goto loopB;} /*535-5*/
}
loopA: eq_l = 1; eq_r = 1; /* splitting type A */ /* left <= median < right */
for (;;) {
for (;;) {
if ((l += size) == r)
{l -= size; if (l != m) mmswap(m,l); l -= size; goto fin;}
if (l == m) continue;
if ((t = (*cmp)(l,m)) > 0) {eq_r = 0; break;}
if (t < 0) eq_l = 0;
}
for (;;) {
if (l == (r -= size))
{l -= size; if (l != m) mmswap(m,l); l -= size; goto fin;}
if (r == m) {m = l; break;}
if ((t = (*cmp)(r,m)) < 0) {eq_l = 0; break;}
if (t == 0) break;
}
mmswap(l,r); /* swap left and right */
}
loopB: eq_l = 1; eq_r = 1; /* splitting type B */ /* left < median <= right */
for (;;) {
for (;;) {
if (l == (r -= size))
{r += size; if (r != m) mmswap(r,m); r += size; goto fin;}
if (r == m) continue;
if ((t = (*cmp)(r,m)) < 0) {eq_l = 0; break;}
if (t > 0) eq_r = 0;
}
for (;;) {
if ((l += size) == r)
{r += size; if (r != m) mmswap(r,m); r += size; goto fin;}
if (l == m) {m = r; break;}
if ((t = (*cmp)(l,m)) > 0) {eq_r = 0; break;}
if (t == 0) break;
}
mmswap(l,r); /* swap left and right */
}
fin:
if (eq_l == 0) /* need to sort left side */
if (eq_r == 0) /* need to sort right side */
if (l-L < R-r) {PUSH(r,R); R = l;} /* sort left side first */
else {PUSH(L,l); L = r;} /* sort right side first */
else R = l; /* need to sort left side only */
else if (eq_r == 0) L = r; /* need to sort right side only */
else goto nxt; /* need not to sort both sides */
}
}
char *
ruby_strdup(str)
const char *str;
{
char *tmp;
int len = strlen(str) + 1;
tmp = xmalloc(len);
if (tmp == NULL) return NULL;
memcpy(tmp, str, len);
return tmp;
}
char *
ruby_getcwd()
{
int size = 200;
char *buf = xmalloc(size);
while (!getcwd(buf, size)) {
if (errno != ERANGE) rb_sys_fail(0);
size *= 2;
buf = xrealloc(buf, size);
}
return buf;
}
/* copyright notice for strtod implementation --
*
* Copyright (c) 1988-1993 The Regents of the University of California.
* Copyright (c) 1994 Sun Microsystems, Inc.
*
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies. The University of California
* makes no representations about the suitability of this
* software for any purpose. It is provided "as is" without
* express or implied warranty.
*
*/
#define TRUE 1
#define FALSE 0
static int maxExponent = 511; /* Largest possible base 10 exponent. Any
* exponent larger than this will already
* produce underflow or overflow, so there's
* no need to worry about additional digits.
*/
static double powersOf10[] = { /* Table giving binary powers of 10. Entry */
10.0, /* is 10^2^i. Used to convert decimal */
100.0, /* exponents into floating-point numbers. */
1.0e4,
1.0e8,
1.0e16,
1.0e32,
1.0e64,
1.0e128,
1.0e256
};
/*
*----------------------------------------------------------------------
*
* strtod --
*
* This procedure converts a floating-point number from an ASCII
* decimal representation to internal double-precision format.
*
* Results:
* The return value is the double-precision floating-point
* representation of the characters in string. If endPtr isn't
* NULL, then *endPtr is filled in with the address of the
* next character after the last one that was part of the
* floating-point number.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
double
ruby_strtod(string, endPtr)
const char *string; /* A decimal ASCII floating-point number,
* optionally preceded by white space.
* Must have form "-I.FE-X", where I is the
* integer part of the mantissa, F is the
* fractional part of the mantissa, and X
* is the exponent. Either of the signs
* may be "+", "-", or omitted. Either I
* or F may be omitted, or both. The decimal
* point isn't necessary unless F is present.
* The "E" may actually be an "e". E and X
* may both be omitted (but not just one).
*/
char **endPtr; /* If non-NULL, store terminating character's
* address here. */
{
int sign, expSign = FALSE;
double fraction, dblExp, *d;
register const char *p;
register int c;
int exp = 0; /* Exponent read from "EX" field. */
int fracExp = 0; /* Exponent that derives from the fractional
* part. Under normal circumstatnces, it is
* the negative of the number of digits in F.
* However, if I is very long, the last digits
* of I get dropped (otherwise a long I with a
* large negative exponent could cause an
* unnecessary overflow on I alone). In this
* case, fracExp is incremented one for each
* dropped digit. */
int mantSize; /* Number of digits in mantissa. */
int decPt; /* Number of mantissa digits BEFORE decimal
* point. */
const char *pExp; /* Temporarily holds location of exponent
* in string. */
/*
* Strip off leading blanks and check for a sign.
*/
errno = 0;
p = string;
while (ISSPACE(*p)) {
p += 1;
}
if (*p == '-') {
sign = TRUE;
p += 1;
}
else {
if (*p == '+') {
p += 1;
}
sign = FALSE;
}
/*
* Count the number of digits in the mantissa (including the decimal
* point), and also locate the decimal point.
*/
decPt = -1;
for (mantSize = 0; ; mantSize += 1) {
c = *p;
if (!ISDIGIT(c)) {
if ((c != '.') || (decPt >= 0)) {
break;
}
decPt = mantSize;
}
p += 1;
}
/*
* Now suck up the digits in the mantissa. Use two integers to
* collect 9 digits each (this is faster than using floating-point).
* If the mantissa has more than 18 digits, ignore the extras, since
* they can't affect the value anyway.
*/
pExp = p;
p -= mantSize;
if (decPt < 0) {
decPt = mantSize;
}
else {
mantSize -= 1; /* One of the digits was the point. */
}
if (mantSize > 18) {
fracExp = decPt - 18;
mantSize = 18;
}
else {
fracExp = decPt - mantSize;
}
if (mantSize == 0) {
fraction = 0.0;
p = string;
goto done;
}
else {
int frac1, frac2;
frac1 = 0;
for ( ; mantSize > 9; mantSize -= 1) {
c = *p;
p += 1;
if (c == '.') {
c = *p;
p += 1;
}
frac1 = 10*frac1 + (c - '0');
}
frac2 = 0;
for (; mantSize > 0; mantSize -= 1) {
c = *p;
p += 1;
if (c == '.') {
c = *p;
p += 1;
}
frac2 = 10*frac2 + (c - '0');
}
fraction = (1.0e9 * frac1) + frac2;
}
/*
* Skim off the exponent.
*/
p = pExp;
if ((*p == 'E') || (*p == 'e')) {
p += 1;
if (*p == '-') {
expSign = TRUE;
p += 1;
}
else {
if (*p == '+') {
p += 1;
}
expSign = FALSE;
}
while (ISDIGIT(*p)) {
exp = exp * 10 + (*p - '0');
p += 1;
}
}
if (expSign) {
exp = fracExp - exp;
}
else {
exp = fracExp + exp;
}
/*
* Generate a floating-point number that represents the exponent.
* Do this by processing the exponent one bit at a time to combine
* many powers of 2 of 10. Then combine the exponent with the
* fraction.
*/
if (exp < 0) {
expSign = TRUE;
exp = -exp;
}
else {
expSign = FALSE;
}
if (exp > maxExponent) {
exp = maxExponent;
errno = ERANGE;
}
dblExp = 1.0;
for (d = powersOf10; exp != 0; exp >>= 1, d += 1) {
if (exp & 01) {
dblExp *= *d;
}
}
if (expSign) {
fraction /= dblExp;
}
else {
fraction *= dblExp;
}
done:
if (endPtr != NULL) {
*endPtr = (char *) p;
}
if (sign) {
return -fraction;
}
return fraction;
}