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util.c
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1993-08-13
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/* util.c -- utility functions for gzip support
* Copyright (C) 1992-1993 Jean-loup Gailly
* This is free software; you can redistribute it and/or modify it under the
* terms of the GNU General Public License, see the file COPYING.
*/
#ifdef RCSID
static char rcsid[] = "$Id: util.c,v 0.15 1993/06/15 09:04:13 jloup Exp $";
#endif
#include <ctype.h>
#include <errno.h>
#include <sys/types.h>
#include "tailor.h"
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifndef NO_FCNTL_H
# include <fcntl.h>
#endif
#if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
# include <stdlib.h>
#else
extern int errno;
#endif
#include "gzip.h"
#include "crypt.h"
extern ulg crc_32_tab[]; /* crc table, defined below */
/* ===========================================================================
* Copy input to output unchanged: zcat == cat with --force.
* IN assertion: insize bytes have already been read in inbuf.
*/
int copy(in, out)
int in, out; /* input and output file descriptors */
{
errno = 0;
while (insize != 0 && (int)insize != EOF) {
write_buf(out, (char*)inbuf, insize);
bytes_out += insize;
insize = read(in, (char*)inbuf, INBUFSIZ);
}
if ((int)insize == EOF && errno != 0) {
read_error();
}
bytes_in = bytes_out;
return OK;
}
/* ===========================================================================
* Run a set of bytes through the crc shift register. If s is a NULL
* pointer, then initialize the crc shift register contents instead.
* Return the current crc in either case.
*/
ulg updcrc(s, n)
uch *s; /* pointer to bytes to pump through */
unsigned n; /* number of bytes in s[] */
{
register ulg c; /* temporary variable */
static ulg crc = (ulg)0xffffffffL; /* shift register contents */
if (s == NULL) {
c = 0xffffffffL;
} else {
c = crc;
if (n) do {
c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
} while (--n);
}
crc = c;
return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */
}
/* ===========================================================================
* Clear input and output buffers
*/
void clear_bufs()
{
outcnt = 0;
insize = inptr = 0;
bytes_in = bytes_out = 0L;
}
/* ===========================================================================
* Fill the input buffer. This is called only when the buffer is empty.
*/
int fill_inbuf(eof_ok)
int eof_ok; /* set if EOF acceptable as a result */
{
int len;
/* Read as much as possible */
insize = 0;
errno = 0;
do {
len = read(ifd, (char*)inbuf+insize, INBUFSIZ-insize);
if (len == 0 || len == EOF) break;
insize += len;
} while (insize < INBUFSIZ);
if (insize == 0) {
if (eof_ok) return EOF;
read_error();
}
bytes_in += (ulg)insize;
inptr = 1;
return inbuf[0];
}
/* ===========================================================================
* Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
* (used for the compressed data only)
*/
void flush_outbuf()
{
if (outcnt == 0) return;
write_buf(ofd, (char *)outbuf, outcnt);
bytes_out += (ulg)outcnt;
outcnt = 0;
}
/* ===========================================================================
* Write the output window window[0..outcnt-1] and update crc and bytes_out.
* (Used for the decompressed data only.)
*/
void flush_window()
{
if (outcnt == 0) return;
updcrc(window, outcnt);
if (!test) {
write_buf(ofd, (char *)window, outcnt);
}
bytes_out += (ulg)outcnt;
outcnt = 0;
}
/* ===========================================================================
* Does the same as write(), but also handles partial pipe writes and checks
* for error return.
*/
void write_buf(fd, buf, cnt)
int fd;
voidp buf;
unsigned cnt;
{
unsigned n;
while ((n = write(fd, buf, cnt)) != cnt) {
if (n == (unsigned)(-1)) {
write_error();
}
cnt -= n;
buf = (voidp)((char*)buf+n);
}
}
/* ========================================================================
* Put string s in lower case, return s.
*/
char *strlwr(s)
char *s;
{
char *t;
for (t = s; *t; t++) *t = tolow(*t);
return s;
}
/* ========================================================================
* Return the base name of a file (remove any directory prefix and
* any version suffix). For systems with file names that are not
* case sensitive, force the base name to lower case.
*/
char *basename(fname)
char *fname;
{
char *p;
if ((p = strrchr(fname, PATH_SEP)) != NULL) fname = p+1;
#ifdef PATH_SEP2
if ((p = strrchr(fname, PATH_SEP2)) != NULL) fname = p+1;
#endif
#ifdef PATH_SEP3
if ((p = strrchr(fname, PATH_SEP3)) != NULL) fname = p+1;
#endif
#ifdef SUFFIX_SEP
if ((p = strrchr(fname, SUFFIX_SEP)) != NULL) *p = '\0';
#endif
if (casemap('A') == 'a') strlwr(fname);
return fname;
}
/* ========================================================================
* Make a file name legal for file systems not allowing file names with
* multiple dots or starting with a dot (such as MSDOS), by changing
* all dots except the last one into underlines. A target dependent
* function can be used instead of this simple function by defining the macro
* MAKE_LEGAL_NAME in tailor.h and providing the function in a target
* dependent module.
*/
void make_simple_name(name)
char *name;
{
char *p = strrchr(name, '.');
if (p == NULL) return;
if (p == name) p++;
do {
if (*--p == '.') *p = '_';
} while (p != name);
}
#if defined(NO_STRING_H) && !defined(STDC_HEADERS)
/* Provide missing strspn and strcspn functions. */
# ifndef __STDC__
# define const
# endif
int strspn OF((const char *s, const char *accept));
int strcspn OF((const char *s, const char *reject));
/* ========================================================================
* Return the length of the maximum initial segment
* of s which contains only characters in accept.
*/
int strspn(s, accept)
const char *s;
const char *accept;
{
register const char *p;
register const char *a;
register int count = 0;
for (p = s; *p != '\0'; ++p) {
for (a = accept; *a != '\0'; ++a) {
if (*p == *a) break;
}
if (*a == '\0') return count;
++count;
}
return count;
}
/* ========================================================================
* Return the length of the maximum inital segment of s
* which contains no characters from reject.
*/
int strcspn(s, reject)
const char *s;
const char *reject;
{
register int count = 0;
while (*s != '\0') {
if (strchr(reject, *s++) != NULL) return count;
++count;
}
return count;
}
#endif /* NO_STRING_H */
/* ========================================================================
* Add an environment variable (if any) before argv, and update argc.
* Return the expanded environment variable to be freed later, or NULL
* if no options were added to argv.
*/
#define SEPARATOR " \t" /* separators in env variable */
char *add_envopt(argcp, argvp, env)
int *argcp; /* pointer to argc */
char ***argvp; /* pointer to argv */
char *env; /* name of environment variable */
{
char *p; /* running pointer through env variable */
char **oargv; /* runs through old argv array */
char **nargv; /* runs through new argv array */
int oargc = *argcp; /* old argc */
int nargc = 0; /* number of arguments in env variable */
env = (char*)getenv(env);
if (env == NULL) return NULL;
p = (char*)xmalloc(strlen(env)+1);
env = strcpy(p, env); /* keep env variable intact */
for (p = env; *p; nargc++ ) { /* move through env */
p += strspn(p, SEPARATOR); /* skip leading separators */
if (*p == '\0') break;
p += strcspn(p, SEPARATOR); /* find end of word */
if (*p) *p++ = '\0'; /* mark it */
}
if (nargc == 0) {
free(env);
return NULL;
}
*argcp += nargc;
/* Allocate the new argv array, with an extra element just in case
* the original arg list did not end with a NULL.
*/
nargv = (char**)calloc(*argcp+1, sizeof(char *));
if (nargv == NULL) error("out of memory");
oargv = *argvp;
*argvp = nargv;
/* Copy the program name first */
if (oargc-- < 0) error("argc<=0");
*(nargv++) = *(oargv++);
/* Then copy the environment args */
for (p = env; nargc > 0; nargc--) {
p += strspn(p, SEPARATOR); /* skip separators */
*(nargv++) = p; /* store start */
while (*p++) ; /* skip over word */
}
/* Finally copy the old args and add a NULL (usual convention) */
while (oargc--) *(nargv++) = *(oargv++);
*nargv = NULL;
return env;
}
/* ========================================================================
* Error handlers.
*/
void error(m)
char *m;
{
fprintf(stderr, "\n%s: %s: %s\n", progname, ifname, m);
abort_gzip();
}
void warn(a, b)
char *a, *b; /* message strings juxtaposed in output */
{
WARN((stderr, "%s: %s: warning: %s%s\n", progname, ifname, a, b));
}
void read_error()
{
fprintf(stderr, "\n%s: ", progname);
if (errno != 0) {
perror(ifname);
} else {
fprintf(stderr, "%s: unexpected end of file\n", ifname);
}
abort_gzip();
}
void write_error()
{
fprintf(stderr, "\n%s: ", progname);
perror(ofname);
abort_gzip();
}
/* ========================================================================
* Display compression ratio on the given stream on 6 characters.
*/
void display_ratio(num, den, file)
long num;
long den;
FILE *file;
{
long ratio; /* 1000 times the compression ratio */
if (den == 0) {
ratio = 0; /* no compression */
} else if (den < 2147483L) { /* (2**31 -1)/1000 */
ratio = 1000L*num/den;
} else {
ratio = num/(den/1000L);
}
if (ratio < 0) {
putc('-', file);
ratio = -ratio;
} else {
putc(' ', file);
}
fprintf(file, "%2ld.%1ld%%", ratio / 10L, ratio % 10L);
}
/* ========================================================================
* Semi-safe malloc -- never returns NULL.
*/
voidp xmalloc (size)
unsigned size;
{
voidp cp = (voidp)malloc (size);
if (cp == NULL) error("out of memory");
return cp;
}
/* ========================================================================
* Table of CRC-32's of all single-byte values (made by makecrc.c)
*/
ulg crc_32_tab[] = {
0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
0x2d02ef8dL
};