/* util.c -- utility functions for gzip support Copyright (C) 1997-1999, 2001-2002, 2006, 2009-2016 Free Software Foundation, Inc. Copyright (C) 1992-1993 Jean-loup Gailly 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 3, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include #include #include #include #include #include #include "tailor.h" #include "gzip.h" #include #ifndef CHAR_BIT # define CHAR_BIT 8 #endif static int write_buffer (int, voidp, unsigned int); /* ======================================================================== * Table of CRC-32's of all single-byte values (made by makecrc.c) */ static const 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 }; /* =========================================================================== * Copy input to output unchanged: zcat == cat with --force. * IN assertion: insize bytes have already been read in inbuf and inptr bytes * already processed or copied. */ int copy(in, out) int in, out; /* input and output file descriptors */ { int got; errno = 0; while (insize > inptr) { write_buf(out, (char*)inbuf + inptr, insize - inptr); bytes_out += insize - inptr; got = read_buffer (in, (char *) inbuf, INBUFSIZ); if (got == -1) read_error(); bytes_in += got; insize = (unsigned)got; inptr = 0; } 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; do { len = read_buffer (ifd, (char *) inbuf + insize, INBUFSIZ - insize); if (len == 0) break; if (len == -1) { read_error(); break; } insize += len; } while (insize < INBUFSIZ); if (insize == 0) { if (eof_ok) return EOF; flush_window(); errno = 0; read_error(); } bytes_in += (off_t)insize; inptr = 1; return inbuf[0]; } /* Like the standard read function, except do not attempt to read more than INT_MAX bytes at a time. */ int read_buffer (fd, buf, cnt) int fd; voidp buf; unsigned int cnt; { int len; if (INT_MAX < cnt) cnt = INT_MAX; len = read (fd, buf, cnt); #if defined F_SETFL && O_NONBLOCK && defined EAGAIN /* Input files are opened O_NONBLOCK for security reasons. On some file systems this can cause read to fail with errno == EAGAIN. */ if (len < 0 && errno == EAGAIN) { int flags = fcntl (fd, F_GETFL); if (0 <= flags) { if (! (flags & O_NONBLOCK)) errno = EAGAIN; else if (fcntl (fd, F_SETFL, flags & ~O_NONBLOCK) != -1) len = read (fd, buf, cnt); } } #endif return len; } /* Likewise for 'write'. */ static int write_buffer (fd, buf, cnt) int fd; voidp buf; unsigned int cnt; { if (INT_MAX < cnt) cnt = INT_MAX; return write (fd, buf, cnt); } /* =========================================================================== * 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 += (off_t)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 += (off_t)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_buffer (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 ((unsigned char) *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 * gzip_base_name (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; } /* ======================================================================== * Unlink a file, working around the unlink readonly bug (if present). */ int xunlink (filename) char *filename; { int r = unlink (filename); #ifdef UNLINK_READONLY_BUG if (r != 0) { int e = errno; if (chmod (filename, S_IWUSR) != 0) { errno = e; return -1; } r = unlink (filename); } #endif return r; } /* ======================================================================== * 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); } /* Convert the value of the environment variable ENVVAR_NAME to a newly allocated argument vector, and set *ARGCP and *ARGVP to the number of arguments and to the vector, respectively. Make the new vector's zeroth element equal to the old **ARGVP. Return a pointer to the newly allocated string storage. If the vector would be empty, do not allocate storage, do not set *ARGCP and *ARGVP, and return NULL. */ #define SEPARATOR " \t" /* separators in env variable */ char *add_envopt( int *argcp, /* pointer to argc */ char ***argvp, /* pointer to argv */ char const *envvar_name) /* 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 nargc = 0; /* number of arguments in env variable */ char *env_val; env_val = getenv(envvar_name); if (env_val == NULL) return NULL; env_val = xstrdup (env_val); for (p = env_val; *p; nargc++ ) { /* move through env_val */ 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_val); return NULL; } *argcp = nargc + 1; /* Allocate the new argv array, with an extra element just in case * the original arg list did not end with a NULL. */ nargv = xcalloc (*argcp + 1, sizeof (char *)); oargv = *argvp; *argvp = nargv; /* Copy the program name first */ *nargv++ = *oargv; /* Then copy the environment args */ for (p = env_val; nargc > 0; nargc--) { p += strspn(p, SEPARATOR); /* skip separators */ *(nargv++) = p; /* store start */ while (*p++) ; /* skip over word */ } *nargv = NULL; return env_val; } /* ======================================================================== * Error handlers. */ void gzip_error (char const *m) { fprintf (stderr, "\n%s: %s: %s\n", program_name, ifname, m); abort_gzip(); } void xalloc_die () { fprintf (stderr, "\n%s: memory_exhausted\n", program_name); abort_gzip (); } void warning (char const *m) { WARN ((stderr, "%s: %s: warning: %s\n", program_name, ifname, m)); } void read_error() { int e = errno; fprintf (stderr, "\n%s: ", program_name); if (e != 0) { errno = e; perror(ifname); } else { fprintf(stderr, "%s: unexpected end of file\n", ifname); } abort_gzip(); } void write_error() { int e = errno; fprintf (stderr, "\n%s: ", program_name); errno = e; perror(ofname); abort_gzip(); } /* ======================================================================== * Display compression ratio on the given stream on 6 characters. */ void display_ratio(num, den, file) off_t num; off_t den; FILE *file; { fprintf(file, "%5.1f%%", den == 0 ? 0 : 100.0 * num / den); } /* ======================================================================== * Print an off_t. There's no completely portable way to use printf, * so we do it ourselves. */ void fprint_off(file, offset, width) FILE *file; off_t offset; int width; { char buf[CHAR_BIT * sizeof (off_t)]; char *p = buf + sizeof buf; /* Don't negate offset here; it might overflow. */ if (offset < 0) { do *--p = '0' - offset % 10; while ((offset /= 10) != 0); *--p = '-'; } else { do *--p = '0' + offset % 10; while ((offset /= 10) != 0); } width -= buf + sizeof buf - p; while (0 < width--) { putc (' ', file); } for (; p < buf + sizeof buf; p++) putc (*p, file); }