/* $NetBSD: gzip.c,v 1.109 2015/10/27 07:36:18 mrg Exp $ */ /* * Copyright (c) 1997, 1998, 2003, 2004, 2006 Matthew R. Green * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #ifndef lint __COPYRIGHT("@(#) Copyright (c) 1997, 1998, 2003, 2004, 2006\ Matthew R. Green. All rights reserved."); __RCSID("$NetBSD: gzip.c,v 1.109 2015/10/27 07:36:18 mrg Exp $"); #endif /* not lint */ /* * gzip.c -- GPL free gzip using zlib. * * RFC 1950 covers the zlib format * RFC 1951 covers the deflate format * RFC 1952 covers the gzip format * * TODO: * - use mmap where possible * - handle some signals better (remove outfile?) * - make bzip2/compress -v/-t/-l support work as well as possible */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef PRIdOFF #define PRIdOFF PRId64 #endif /* what type of file are we dealing with */ enum filetype { FT_GZIP, #ifndef NO_BZIP2_SUPPORT FT_BZIP2, #endif #ifndef NO_COMPRESS_SUPPORT FT_Z, #endif #ifndef NO_PACK_SUPPORT FT_PACK, #endif #ifndef NO_XZ_SUPPORT FT_XZ, #endif FT_LAST, FT_UNKNOWN }; #ifndef NO_BZIP2_SUPPORT #include #define BZ2_SUFFIX ".bz2" #define BZIP2_MAGIC "\102\132\150" #endif #ifndef NO_COMPRESS_SUPPORT #define Z_SUFFIX ".Z" #define Z_MAGIC "\037\235" #endif #ifndef NO_PACK_SUPPORT #define PACK_MAGIC "\037\036" #endif #ifndef NO_XZ_SUPPORT #include #define XZ_SUFFIX ".xz" #define XZ_MAGIC "\3757zXZ" #endif #define GZ_SUFFIX ".gz" #define BUFLEN (64 * 1024) #define GZIP_MAGIC0 0x1F #define GZIP_MAGIC1 0x8B #define GZIP_OMAGIC1 0x9E #define GZIP_TIMESTAMP (off_t)4 #define GZIP_ORIGNAME (off_t)10 #define HEAD_CRC 0x02 #define EXTRA_FIELD 0x04 #define ORIG_NAME 0x08 #define COMMENT 0x10 #define OS_CODE 3 /* Unix */ typedef struct { const char *zipped; int ziplen; const char *normal; /* for unzip - must not be longer than zipped */ } suffixes_t; static suffixes_t suffixes[] = { #define SUFFIX(Z, N) {Z, sizeof Z - 1, N} SUFFIX(GZ_SUFFIX, ""), /* Overwritten by -S .xxx */ #ifndef SMALL SUFFIX(GZ_SUFFIX, ""), SUFFIX(".z", ""), SUFFIX("-gz", ""), SUFFIX("-z", ""), SUFFIX("_z", ""), SUFFIX(".taz", ".tar"), SUFFIX(".tgz", ".tar"), #ifndef NO_BZIP2_SUPPORT SUFFIX(BZ2_SUFFIX, ""), #endif #ifndef NO_COMPRESS_SUPPORT SUFFIX(Z_SUFFIX, ""), #endif #ifndef NO_XZ_SUPPORT SUFFIX(XZ_SUFFIX, ""), #endif SUFFIX(GZ_SUFFIX, ""), /* Overwritten by -S "" */ #endif /* SMALL */ #undef SUFFIX }; #define NUM_SUFFIXES (sizeof suffixes / sizeof suffixes[0]) #define SUFFIX_MAXLEN 30 static const char gzip_version[] = "NetBSD gzip 20150113"; static int cflag; /* stdout mode */ static int dflag; /* decompress mode */ static int lflag; /* list mode */ static int numflag = 6; /* gzip -1..-9 value */ #ifndef SMALL static int fflag; /* force mode */ static int kflag; /* don't delete input files */ static int nflag; /* don't save name/timestamp */ static int Nflag; /* don't restore name/timestamp */ static int qflag; /* quiet mode */ static int rflag; /* recursive mode */ static int tflag; /* test */ static int vflag; /* verbose mode */ #else #define qflag 0 #define tflag 0 #endif static int exit_value = 0; /* exit value */ static char *infile; /* name of file coming in */ static void maybe_err(const char *fmt, ...) __printflike(1, 2) __dead; #if !defined(NO_BZIP2_SUPPORT) || !defined(NO_PACK_SUPPORT) || \ !defined(NO_XZ_SUPPORT) static void maybe_errx(const char *fmt, ...) __printflike(1, 2) __dead; #endif static void maybe_warn(const char *fmt, ...) __printflike(1, 2); static void maybe_warnx(const char *fmt, ...) __printflike(1, 2); static enum filetype file_gettype(u_char *); #ifdef SMALL #define gz_compress(if, of, sz, fn, tm) gz_compress(if, of, sz) #endif static off_t gz_compress(int, int, off_t *, const char *, uint32_t); static off_t gz_uncompress(int, int, char *, size_t, off_t *, const char *); static off_t file_compress(char *, char *, size_t); static off_t file_uncompress(char *, char *, size_t); static void handle_pathname(char *); static void handle_file(char *, struct stat *); static void handle_stdin(void); static void handle_stdout(void); static void print_ratio(off_t, off_t, FILE *); static void print_list(int fd, off_t, const char *, time_t); __dead static void usage(void); __dead static void display_version(void); static const suffixes_t *check_suffix(char *, int); static ssize_t read_retry(int, void *, size_t); #ifdef SMALL #define unlink_input(f, sb) unlink(f) #else static off_t cat_fd(unsigned char *, size_t, off_t *, int fd); static void prepend_gzip(char *, int *, char ***); static void handle_dir(char *); static void print_verbage(const char *, const char *, off_t, off_t); static void print_test(const char *, int); static void copymodes(int fd, const struct stat *, const char *file); static int check_outfile(const char *outfile); #endif #ifndef NO_BZIP2_SUPPORT static off_t unbzip2(int, int, char *, size_t, off_t *); #endif #ifndef NO_COMPRESS_SUPPORT static FILE *zdopen(int); static off_t zuncompress(FILE *, FILE *, char *, size_t, off_t *); #endif #ifndef NO_PACK_SUPPORT static off_t unpack(int, int, char *, size_t, off_t *); #endif #ifndef NO_XZ_SUPPORT static off_t unxz(int, int, char *, size_t, off_t *); #endif #ifdef SMALL #define getopt_long(a,b,c,d,e) getopt(a,b,c) #else static const struct option longopts[] = { { "stdout", no_argument, 0, 'c' }, { "to-stdout", no_argument, 0, 'c' }, { "decompress", no_argument, 0, 'd' }, { "uncompress", no_argument, 0, 'd' }, { "force", no_argument, 0, 'f' }, { "help", no_argument, 0, 'h' }, { "keep", no_argument, 0, 'k' }, { "list", no_argument, 0, 'l' }, { "no-name", no_argument, 0, 'n' }, { "name", no_argument, 0, 'N' }, { "quiet", no_argument, 0, 'q' }, { "recursive", no_argument, 0, 'r' }, { "suffix", required_argument, 0, 'S' }, { "test", no_argument, 0, 't' }, { "verbose", no_argument, 0, 'v' }, { "version", no_argument, 0, 'V' }, { "fast", no_argument, 0, '1' }, { "best", no_argument, 0, '9' }, #if 0 /* * This is what else GNU gzip implements. --ascii isn't useful * on NetBSD, and I don't care to have a --license. */ { "ascii", no_argument, 0, 'a' }, { "license", no_argument, 0, 'L' }, #endif { NULL, no_argument, 0, 0 }, }; #endif int main(int argc, char **argv) { const char *progname = getprogname(); #ifndef SMALL char *gzip; int len; #endif int ch; /* XXX set up signals */ #ifndef SMALL if ((gzip = getenv("GZIP")) != NULL) prepend_gzip(gzip, &argc, &argv); #endif /* * XXX * handle being called `gunzip', `zcat' and `gzcat' */ if (strcmp(progname, "gunzip") == 0) dflag = 1; else if (strcmp(progname, "zcat") == 0 || strcmp(progname, "gzcat") == 0) dflag = cflag = 1; #ifdef SMALL #define OPT_LIST "123456789cdhlV" #else #define OPT_LIST "123456789cdfhklNnqrS:tVv" #endif while ((ch = getopt_long(argc, argv, OPT_LIST, longopts, NULL)) != -1) { switch (ch) { case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': numflag = ch - '0'; break; case 'c': cflag = 1; break; case 'd': dflag = 1; break; case 'l': lflag = 1; dflag = 1; break; case 'V': display_version(); /* NOTREACHED */ #ifndef SMALL case 'f': fflag = 1; break; case 'k': kflag = 1; break; case 'N': nflag = 0; Nflag = 1; break; case 'n': nflag = 1; Nflag = 0; break; case 'q': qflag = 1; break; case 'r': rflag = 1; break; case 'S': len = strlen(optarg); if (len != 0) { if (len > SUFFIX_MAXLEN) errx(1, "incorrect suffix: '%s'", optarg); suffixes[0].zipped = optarg; suffixes[0].ziplen = len; } else { suffixes[NUM_SUFFIXES - 1].zipped = ""; suffixes[NUM_SUFFIXES - 1].ziplen = 0; } break; case 't': cflag = 1; tflag = 1; dflag = 1; break; case 'v': vflag = 1; break; #endif default: usage(); /* NOTREACHED */ } } argv += optind; argc -= optind; if (argc == 0) { if (dflag) /* stdin mode */ handle_stdin(); else /* stdout mode */ handle_stdout(); } else { do { handle_pathname(argv[0]); } while (*++argv); } #ifndef SMALL if (qflag == 0 && lflag && argc > 1) print_list(-1, 0, "(totals)", 0); #endif exit(exit_value); } /* maybe print a warning */ void maybe_warn(const char *fmt, ...) { va_list ap; if (qflag == 0) { va_start(ap, fmt); vwarn(fmt, ap); va_end(ap); } if (exit_value == 0) exit_value = 1; } /* ... without an errno. */ void maybe_warnx(const char *fmt, ...) { va_list ap; if (qflag == 0) { va_start(ap, fmt); vwarnx(fmt, ap); va_end(ap); } if (exit_value == 0) exit_value = 1; } /* maybe print an error */ void maybe_err(const char *fmt, ...) { va_list ap; if (qflag == 0) { va_start(ap, fmt); vwarn(fmt, ap); va_end(ap); } exit(2); } #if !defined(NO_BZIP2_SUPPORT) || !defined(NO_PACK_SUPPORT) || \ !defined(NO_XZ_SUPPORT) /* ... without an errno. */ void maybe_errx(const char *fmt, ...) { va_list ap; if (qflag == 0) { va_start(ap, fmt); vwarnx(fmt, ap); va_end(ap); } exit(2); } #endif #ifndef SMALL /* split up $GZIP and prepend it to the argument list */ static void prepend_gzip(char *gzip, int *argc, char ***argv) { char *s, **nargv, **ac; int nenvarg = 0, i; /* scan how many arguments there are */ for (s = gzip;;) { while (*s == ' ' || *s == '\t') s++; if (*s == 0) goto count_done; nenvarg++; while (*s != ' ' && *s != '\t') if (*s++ == 0) goto count_done; } count_done: /* punt early */ if (nenvarg == 0) return; *argc += nenvarg; ac = *argv; nargv = (char **)malloc((*argc + 1) * sizeof(char *)); if (nargv == NULL) maybe_err("malloc"); /* stash this away */ *argv = nargv; /* copy the program name first */ i = 0; nargv[i++] = *(ac++); /* take a copy of $GZIP and add it to the array */ s = strdup(gzip); if (s == NULL) maybe_err("strdup"); for (;;) { /* Skip whitespaces. */ while (*s == ' ' || *s == '\t') s++; if (*s == 0) goto copy_done; nargv[i++] = s; /* Find the end of this argument. */ while (*s != ' ' && *s != '\t') if (*s++ == 0) /* Argument followed by NUL. */ goto copy_done; /* Terminate by overwriting ' ' or '\t' with NUL. */ *s++ = 0; } copy_done: /* copy the original arguments and a NULL */ while (*ac) nargv[i++] = *(ac++); nargv[i] = NULL; } #endif /* compress input to output. Return bytes read, -1 on error */ static off_t gz_compress(int in, int out, off_t *gsizep, const char *origname, uint32_t mtime) { z_stream z; char *outbufp, *inbufp; off_t in_tot = 0, out_tot = 0; ssize_t in_size; int i, error; uLong crc; #ifdef SMALL static char header[] = { GZIP_MAGIC0, GZIP_MAGIC1, Z_DEFLATED, 0, 0, 0, 0, 0, 0, OS_CODE }; #endif outbufp = malloc(BUFLEN); inbufp = malloc(BUFLEN); if (outbufp == NULL || inbufp == NULL) { maybe_err("malloc failed"); goto out; } memset(&z, 0, sizeof z); z.zalloc = Z_NULL; z.zfree = Z_NULL; z.opaque = 0; #ifdef SMALL memcpy(outbufp, header, sizeof header); i = sizeof header; #else if (nflag != 0) { mtime = 0; origname = ""; } i = snprintf(outbufp, BUFLEN, "%c%c%c%c%c%c%c%c%c%c%s", GZIP_MAGIC0, GZIP_MAGIC1, Z_DEFLATED, *origname ? ORIG_NAME : 0, mtime & 0xff, (mtime >> 8) & 0xff, (mtime >> 16) & 0xff, (mtime >> 24) & 0xff, numflag == 1 ? 4 : numflag == 9 ? 2 : 0, OS_CODE, origname); if (i >= BUFLEN) /* this need PATH_MAX > BUFLEN ... */ maybe_err("snprintf"); if (*origname) i++; #endif z.next_out = (unsigned char *)outbufp + i; z.avail_out = BUFLEN - i; error = deflateInit2(&z, numflag, Z_DEFLATED, (-MAX_WBITS), 8, Z_DEFAULT_STRATEGY); if (error != Z_OK) { maybe_warnx("deflateInit2 failed"); in_tot = -1; goto out; } crc = crc32(0L, Z_NULL, 0); for (;;) { if (z.avail_out == 0) { if (write(out, outbufp, BUFLEN) != BUFLEN) { maybe_warn("write"); out_tot = -1; goto out; } out_tot += BUFLEN; z.next_out = (unsigned char *)outbufp; z.avail_out = BUFLEN; } if (z.avail_in == 0) { in_size = read(in, inbufp, BUFLEN); if (in_size < 0) { maybe_warn("read"); in_tot = -1; goto out; } if (in_size == 0) break; crc = crc32(crc, (const Bytef *)inbufp, (unsigned)in_size); in_tot += in_size; z.next_in = (unsigned char *)inbufp; z.avail_in = in_size; } error = deflate(&z, Z_NO_FLUSH); if (error != Z_OK && error != Z_STREAM_END) { maybe_warnx("deflate failed"); in_tot = -1; goto out; } } /* clean up */ for (;;) { size_t len; ssize_t w; error = deflate(&z, Z_FINISH); if (error != Z_OK && error != Z_STREAM_END) { maybe_warnx("deflate failed"); in_tot = -1; goto out; } len = (char *)z.next_out - outbufp; w = write(out, outbufp, len); if (w == -1 || (size_t)w != len) { maybe_warn("write"); out_tot = -1; goto out; } out_tot += len; z.next_out = (unsigned char *)outbufp; z.avail_out = BUFLEN; if (error == Z_STREAM_END) break; } if (deflateEnd(&z) != Z_OK) { maybe_warnx("deflateEnd failed"); in_tot = -1; goto out; } i = snprintf(outbufp, BUFLEN, "%c%c%c%c%c%c%c%c", (int)crc & 0xff, (int)(crc >> 8) & 0xff, (int)(crc >> 16) & 0xff, (int)(crc >> 24) & 0xff, (int)in_tot & 0xff, (int)(in_tot >> 8) & 0xff, (int)(in_tot >> 16) & 0xff, (int)(in_tot >> 24) & 0xff); if (i != 8) maybe_err("snprintf"); #if 0 if (in_tot > 0xffffffff) maybe_warn("input file size >= 4GB cannot be saved"); #endif if (write(out, outbufp, i) != i) { maybe_warn("write"); in_tot = -1; } else out_tot += i; out: if (inbufp != NULL) free(inbufp); if (outbufp != NULL) free(outbufp); if (gsizep) *gsizep = out_tot; return in_tot; } /* * uncompress input to output then close the input. return the * uncompressed size written, and put the compressed sized read * into `*gsizep'. */ static off_t gz_uncompress(int in, int out, char *pre, size_t prelen, off_t *gsizep, const char *filename) { z_stream z; char *outbufp, *inbufp; off_t out_tot = -1, in_tot = 0; uint32_t out_sub_tot = 0; enum { GZSTATE_MAGIC0, GZSTATE_MAGIC1, GZSTATE_METHOD, GZSTATE_FLAGS, GZSTATE_SKIPPING, GZSTATE_EXTRA, GZSTATE_EXTRA2, GZSTATE_EXTRA3, GZSTATE_ORIGNAME, GZSTATE_COMMENT, GZSTATE_HEAD_CRC1, GZSTATE_HEAD_CRC2, GZSTATE_INIT, GZSTATE_READ, GZSTATE_CRC, GZSTATE_LEN, } state = GZSTATE_MAGIC0; int flags = 0, skip_count = 0; int error = Z_STREAM_ERROR, done_reading = 0; uLong crc = 0; ssize_t wr; int needmore = 0; #define ADVANCE() { z.next_in++; z.avail_in--; } if ((outbufp = malloc(BUFLEN)) == NULL) { maybe_err("malloc failed"); goto out2; } if ((inbufp = malloc(BUFLEN)) == NULL) { maybe_err("malloc failed"); goto out1; } memset(&z, 0, sizeof z); z.avail_in = prelen; z.next_in = (unsigned char *)pre; z.avail_out = BUFLEN; z.next_out = (unsigned char *)outbufp; z.zalloc = NULL; z.zfree = NULL; z.opaque = 0; in_tot = prelen; out_tot = 0; for (;;) { if ((z.avail_in == 0 || needmore) && done_reading == 0) { ssize_t in_size; if (z.avail_in > 0) { memmove(inbufp, z.next_in, z.avail_in); } z.next_in = (unsigned char *)inbufp; in_size = read(in, z.next_in + z.avail_in, BUFLEN - z.avail_in); if (in_size == -1) { maybe_warn("failed to read stdin"); goto stop_and_fail; } else if (in_size == 0) { done_reading = 1; } z.avail_in += in_size; needmore = 0; in_tot += in_size; } if (z.avail_in == 0) { if (done_reading && state != GZSTATE_MAGIC0) { maybe_warnx("%s: unexpected end of file", filename); goto stop_and_fail; } goto stop; } switch (state) { case GZSTATE_MAGIC0: if (*z.next_in != GZIP_MAGIC0) { if (in_tot > 0) { maybe_warnx("%s: trailing garbage " "ignored", filename); goto stop; } maybe_warnx("input not gziped (MAGIC0)"); exit_value = 2; goto stop_and_fail; } ADVANCE(); state++; out_sub_tot = 0; crc = crc32(0L, Z_NULL, 0); break; case GZSTATE_MAGIC1: if (*z.next_in != GZIP_MAGIC1 && *z.next_in != GZIP_OMAGIC1) { maybe_warnx("input not gziped (MAGIC1)"); goto stop_and_fail; } ADVANCE(); state++; break; case GZSTATE_METHOD: if (*z.next_in != Z_DEFLATED) { maybe_warnx("unknown compression method"); goto stop_and_fail; } ADVANCE(); state++; break; case GZSTATE_FLAGS: flags = *z.next_in; ADVANCE(); skip_count = 6; state++; break; case GZSTATE_SKIPPING: if (skip_count > 0) { skip_count--; ADVANCE(); } else state++; break; case GZSTATE_EXTRA: if ((flags & EXTRA_FIELD) == 0) { state = GZSTATE_ORIGNAME; break; } skip_count = *z.next_in; ADVANCE(); state++; break; case GZSTATE_EXTRA2: skip_count |= ((*z.next_in) << 8); ADVANCE(); state++; break; case GZSTATE_EXTRA3: if (skip_count > 0) { skip_count--; ADVANCE(); } else state++; break; case GZSTATE_ORIGNAME: if ((flags & ORIG_NAME) == 0) { state++; break; } if (*z.next_in == 0) state++; ADVANCE(); break; case GZSTATE_COMMENT: if ((flags & COMMENT) == 0) { state++; break; } if (*z.next_in == 0) state++; ADVANCE(); break; case GZSTATE_HEAD_CRC1: if (flags & HEAD_CRC) skip_count = 2; else skip_count = 0; state++; break; case GZSTATE_HEAD_CRC2: if (skip_count > 0) { skip_count--; ADVANCE(); } else state++; break; case GZSTATE_INIT: if (inflateInit2(&z, -MAX_WBITS) != Z_OK) { maybe_warnx("failed to inflateInit"); goto stop_and_fail; } state++; break; case GZSTATE_READ: error = inflate(&z, Z_FINISH); switch (error) { /* Z_BUF_ERROR goes with Z_FINISH... */ case Z_BUF_ERROR: if (z.avail_out > 0 && !done_reading) continue; case Z_STREAM_END: case Z_OK: break; case Z_NEED_DICT: maybe_warnx("Z_NEED_DICT error"); goto stop_and_fail; case Z_DATA_ERROR: maybe_warnx("data stream error"); goto stop_and_fail; case Z_STREAM_ERROR: maybe_warnx("internal stream error"); goto stop_and_fail; case Z_MEM_ERROR: maybe_warnx("memory allocation error"); goto stop_and_fail; default: maybe_warn("unknown error from inflate(): %d", error); } wr = BUFLEN - z.avail_out; if (wr != 0) { crc = crc32(crc, (const Bytef *)outbufp, (unsigned)wr); if ( #ifndef SMALL /* don't write anything with -t */ tflag == 0 && #endif write(out, outbufp, wr) != wr) { maybe_warn("error writing to output"); goto stop_and_fail; } out_tot += wr; out_sub_tot += wr; } if (error == Z_STREAM_END) { inflateEnd(&z); state++; } z.next_out = (unsigned char *)outbufp; z.avail_out = BUFLEN; break; case GZSTATE_CRC: { uLong origcrc; if (z.avail_in < 4) { if (!done_reading) { needmore = 1; continue; } maybe_warnx("truncated input"); goto stop_and_fail; } origcrc = ((unsigned)z.next_in[0] & 0xff) | ((unsigned)z.next_in[1] & 0xff) << 8 | ((unsigned)z.next_in[2] & 0xff) << 16 | ((unsigned)z.next_in[3] & 0xff) << 24; if (origcrc != crc) { maybe_warnx("invalid compressed" " data--crc error"); goto stop_and_fail; } } z.avail_in -= 4; z.next_in += 4; if (!z.avail_in && done_reading) { goto stop; } state++; break; case GZSTATE_LEN: { uLong origlen; if (z.avail_in < 4) { if (!done_reading) { needmore = 1; continue; } maybe_warnx("truncated input"); goto stop_and_fail; } origlen = ((unsigned)z.next_in[0] & 0xff) | ((unsigned)z.next_in[1] & 0xff) << 8 | ((unsigned)z.next_in[2] & 0xff) << 16 | ((unsigned)z.next_in[3] & 0xff) << 24; if (origlen != out_sub_tot) { maybe_warnx("invalid compressed" " data--length error"); goto stop_and_fail; } } z.avail_in -= 4; z.next_in += 4; if (error < 0) { maybe_warnx("decompression error"); goto stop_and_fail; } state = GZSTATE_MAGIC0; break; } continue; stop_and_fail: out_tot = -1; stop: break; } if (state > GZSTATE_INIT) inflateEnd(&z); free(inbufp); out1: free(outbufp); out2: if (gsizep) *gsizep = in_tot; return (out_tot); } #ifndef SMALL /* * set the owner, mode, flags & utimes using the given file descriptor. * file is only used in possible warning messages. */ static void copymodes(int fd, const struct stat *sbp, const char *file) { struct timeval times[2]; struct stat sb; /* * If we have no info on the input, give this file some * default values and return.. */ if (sbp == NULL) { mode_t mask = umask(022); (void)fchmod(fd, DEFFILEMODE & ~mask); (void)umask(mask); return; } sb = *sbp; /* if the chown fails, remove set-id bits as-per compress(1) */ if (fchown(fd, sb.st_uid, sb.st_gid) < 0) { if (errno != EPERM) maybe_warn("couldn't fchown: %s", file); sb.st_mode &= ~(S_ISUID|S_ISGID); } /* we only allow set-id and the 9 normal permission bits */ sb.st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO; if (fchmod(fd, sb.st_mode) < 0) maybe_warn("couldn't fchmod: %s", file); /* only try flags if they exist already */ if (sb.st_flags != 0 && fchflags(fd, sb.st_flags) < 0) maybe_warn("couldn't fchflags: %s", file); TIMESPEC_TO_TIMEVAL(×[0], &sb.st_atimespec); TIMESPEC_TO_TIMEVAL(×[1], &sb.st_mtimespec); if (futimes(fd, times) < 0) maybe_warn("couldn't utimes: %s", file); } #endif /* what sort of file is this? */ static enum filetype file_gettype(u_char *buf) { if (buf[0] == GZIP_MAGIC0 && (buf[1] == GZIP_MAGIC1 || buf[1] == GZIP_OMAGIC1)) return FT_GZIP; else #ifndef NO_BZIP2_SUPPORT if (memcmp(buf, BZIP2_MAGIC, 3) == 0 && buf[3] >= '0' && buf[3] <= '9') return FT_BZIP2; else #endif #ifndef NO_COMPRESS_SUPPORT if (memcmp(buf, Z_MAGIC, 2) == 0) return FT_Z; else #endif #ifndef NO_PACK_SUPPORT if (memcmp(buf, PACK_MAGIC, 2) == 0) return FT_PACK; else #endif #ifndef NO_XZ_SUPPORT if (memcmp(buf, XZ_MAGIC, 4) == 0) /* XXX: We only have 4 bytes */ return FT_XZ; else #endif return FT_UNKNOWN; } #ifndef SMALL /* check the outfile is OK. */ static int check_outfile(const char *outfile) { struct stat sb; int ok = 1; if (lflag == 0 && stat(outfile, &sb) == 0) { if (fflag) unlink(outfile); else if (isatty(STDIN_FILENO)) { char ans[10] = { 'n', '\0' }; /* default */ fprintf(stderr, "%s already exists -- do you wish to " "overwrite (y or n)? " , outfile); (void)fgets(ans, sizeof(ans) - 1, stdin); if (ans[0] != 'y' && ans[0] != 'Y') { fprintf(stderr, "\tnot overwriting\n"); ok = 0; } else unlink(outfile); } else { maybe_warnx("%s already exists -- skipping", outfile); ok = 0; } } return ok; } static void unlink_input(const char *file, const struct stat *sb) { struct stat nsb; if (kflag) return; if (stat(file, &nsb) != 0) /* Must be gone already */ return; if (nsb.st_dev != sb->st_dev || nsb.st_ino != sb->st_ino) /* Definitely a different file */ return; unlink(file); } #endif static const suffixes_t * check_suffix(char *file, int xlate) { const suffixes_t *s; int len = strlen(file); char *sp; for (s = suffixes; s != suffixes + NUM_SUFFIXES; s++) { /* if it doesn't fit in "a.suf", don't bother */ if (s->ziplen >= len) continue; sp = file + len - s->ziplen; if (strcmp(s->zipped, sp) != 0) continue; if (xlate) strcpy(sp, s->normal); return s; } return NULL; } /* * compress the given file: create a corresponding .gz file and remove the * original. */ static off_t file_compress(char *file, char *outfile, size_t outsize) { int in; int out; off_t size, insize; #ifndef SMALL struct stat isb, osb; const suffixes_t *suff; #endif in = open(file, O_RDONLY); if (in == -1) { maybe_warn("can't open %s", file); return -1; } if (cflag == 0) { #ifndef SMALL if (fstat(in, &isb) == 0) { if (isb.st_nlink > 1 && fflag == 0) { maybe_warnx("%s has %d other link%s -- " "skipping", file, isb.st_nlink - 1, isb.st_nlink == 1 ? "" : "s"); close(in); return -1; } } if (fflag == 0 && (suff = check_suffix(file, 0)) && suff->zipped[0] != 0) { maybe_warnx("%s already has %s suffix -- unchanged", file, suff->zipped); close(in); return -1; } #endif /* Add (usually) .gz to filename */ if ((size_t)snprintf(outfile, outsize, "%s%s", file, suffixes[0].zipped) >= outsize) memcpy(outfile + outsize - suffixes[0].ziplen - 1, suffixes[0].zipped, suffixes[0].ziplen + 1); #ifndef SMALL if (check_outfile(outfile) == 0) { close(in); return -1; } #endif } if (cflag == 0) { out = open(outfile, O_WRONLY | O_CREAT | O_EXCL, 0600); if (out == -1) { maybe_warn("could not create output: %s", outfile); fclose(stdin); return -1; } } else out = STDOUT_FILENO; insize = gz_compress(in, out, &size, basename(file), (uint32_t)isb.st_mtime); (void)close(in); /* * If there was an error, insize will be -1. * If we compressed to stdout, just return the size. * Otherwise stat the file and check it is the correct size. * We only blow away the file if we can stat the output and it * has the expected size. */ if (cflag != 0) return insize == -1 ? -1 : size; #ifndef SMALL if (fstat(out, &osb) != 0) { maybe_warn("couldn't stat: %s", outfile); goto bad_outfile; } if (osb.st_size != size) { maybe_warnx("output file: %s wrong size (%" PRIdOFF " != %" PRIdOFF "), deleting", outfile, osb.st_size, size); goto bad_outfile; } copymodes(out, &isb, outfile); #endif if (close(out) == -1) maybe_warn("couldn't close output"); /* output is good, ok to delete input */ unlink_input(file, &isb); return size; #ifndef SMALL bad_outfile: if (close(out) == -1) maybe_warn("couldn't close output"); maybe_warnx("leaving original %s", file); unlink(outfile); return size; #endif } /* uncompress the given file and remove the original */ static off_t file_uncompress(char *file, char *outfile, size_t outsize) { struct stat isb, osb; off_t size; ssize_t rbytes; unsigned char header1[4]; enum filetype method; int fd, ofd, zfd = -1; #ifndef SMALL ssize_t rv; time_t timestamp = 0; char name[PATH_MAX + 1]; #endif /* gather the old name info */ fd = open(file, O_RDONLY); if (fd < 0) { maybe_warn("can't open %s", file); goto lose; } strlcpy(outfile, file, outsize); if (check_suffix(outfile, 1) == NULL && !(cflag || lflag)) { maybe_warnx("%s: unknown suffix -- ignored", file); goto lose; } rbytes = read(fd, header1, sizeof header1); if (rbytes != sizeof header1) { /* we don't want to fail here. */ #ifndef SMALL if (fflag) goto lose; #endif if (rbytes == -1) maybe_warn("can't read %s", file); else goto unexpected_EOF; goto lose; } method = file_gettype(header1); #ifndef SMALL if (fflag == 0 && method == FT_UNKNOWN) { maybe_warnx("%s: not in gzip format", file); goto lose; } #endif #ifndef SMALL if (method == FT_GZIP && Nflag) { unsigned char ts[4]; /* timestamp */ rv = pread(fd, ts, sizeof ts, GZIP_TIMESTAMP); if (rv >= 0 && rv < (ssize_t)(sizeof ts)) goto unexpected_EOF; if (rv == -1) { if (!fflag) maybe_warn("can't read %s", file); goto lose; } timestamp = ts[3] << 24 | ts[2] << 16 | ts[1] << 8 | ts[0]; if (header1[3] & ORIG_NAME) { rbytes = pread(fd, name, sizeof(name) - 1, GZIP_ORIGNAME); if (rbytes < 0) { maybe_warn("can't read %s", file); goto lose; } if (name[0] != '\0') { char *dp, *nf; /* Make sure that name is NUL-terminated */ name[rbytes] = '\0'; /* strip saved directory name */ nf = strrchr(name, '/'); if (nf == NULL) nf = name; else nf++; /* preserve original directory name */ dp = strrchr(file, '/'); if (dp == NULL) dp = file; else dp++; snprintf(outfile, outsize, "%.*s%.*s", (int) (dp - file), file, (int) rbytes, nf); } } } #endif lseek(fd, 0, SEEK_SET); if (cflag == 0 || lflag) { if (fstat(fd, &isb) != 0) goto lose; #ifndef SMALL if (isb.st_nlink > 1 && lflag == 0 && fflag == 0) { maybe_warnx("%s has %d other links -- skipping", file, isb.st_nlink - 1); goto lose; } if (nflag == 0 && timestamp) isb.st_mtime = timestamp; if (check_outfile(outfile) == 0) goto lose; #endif } if (cflag == 0 && lflag == 0) { zfd = open(outfile, O_WRONLY|O_CREAT|O_EXCL, 0600); if (zfd == STDOUT_FILENO) { /* We won't close STDOUT_FILENO later... */ zfd = dup(zfd); close(STDOUT_FILENO); } if (zfd == -1) { maybe_warn("can't open %s", outfile); goto lose; } } else zfd = STDOUT_FILENO; switch (method) { #ifndef NO_BZIP2_SUPPORT case FT_BZIP2: /* XXX */ if (lflag) { maybe_warnx("no -l with bzip2 files"); goto lose; } size = unbzip2(fd, zfd, NULL, 0, NULL); break; #endif #ifndef NO_COMPRESS_SUPPORT case FT_Z: { FILE *in, *out; /* XXX */ if (lflag) { maybe_warnx("no -l with Lempel-Ziv files"); goto lose; } if ((in = zdopen(fd)) == NULL) { maybe_warn("zdopen for read: %s", file); goto lose; } out = fdopen(dup(zfd), "w"); if (out == NULL) { maybe_warn("fdopen for write: %s", outfile); fclose(in); goto lose; } size = zuncompress(in, out, NULL, 0, NULL); /* need to fclose() if ferror() is true... */ if (ferror(in) | fclose(in)) { maybe_warn("failed infile fclose"); unlink(outfile); (void)fclose(out); } if (fclose(out) != 0) { maybe_warn("failed outfile fclose"); unlink(outfile); goto lose; } break; } #endif #ifndef NO_PACK_SUPPORT case FT_PACK: if (lflag) { maybe_warnx("no -l with packed files"); goto lose; } size = unpack(fd, zfd, NULL, 0, NULL); break; #endif #ifndef NO_XZ_SUPPORT case FT_XZ: if (lflag) { maybe_warnx("no -l with xz files"); goto lose; } size = unxz(fd, zfd, NULL, 0, NULL); break; #endif #ifndef SMALL case FT_UNKNOWN: if (lflag) { maybe_warnx("no -l for unknown filetypes"); goto lose; } size = cat_fd(NULL, 0, NULL, fd); break; #endif default: if (lflag) { print_list(fd, isb.st_size, outfile, isb.st_mtime); close(fd); return -1; /* XXX */ } size = gz_uncompress(fd, zfd, NULL, 0, NULL, file); break; } if (close(fd) != 0) maybe_warn("couldn't close input"); if (zfd != STDOUT_FILENO && close(zfd) != 0) maybe_warn("couldn't close output"); if (size == -1) { if (cflag == 0) unlink(outfile); maybe_warnx("%s: uncompress failed", file); return -1; } /* if testing, or we uncompressed to stdout, this is all we need */ #ifndef SMALL if (tflag) return size; #endif /* if we are uncompressing to stdin, don't remove the file. */ if (cflag) return size; /* * if we create a file... */ /* * if we can't stat the file don't remove the file. */ ofd = open(outfile, O_RDWR, 0); if (ofd == -1) { maybe_warn("couldn't open (leaving original): %s", outfile); return -1; } if (fstat(ofd, &osb) != 0) { maybe_warn("couldn't stat (leaving original): %s", outfile); close(ofd); return -1; } if (osb.st_size != size) { maybe_warnx("stat gave different size: %" PRIdOFF " != %" PRIdOFF " (leaving original)", size, osb.st_size); close(ofd); unlink(outfile); return -1; } unlink_input(file, &isb); #ifndef SMALL copymodes(ofd, &isb, outfile); #endif close(ofd); return size; unexpected_EOF: maybe_warnx("%s: unexpected end of file", file); lose: if (fd != -1) close(fd); if (zfd != -1 && zfd != STDOUT_FILENO) close(fd); return -1; } #ifndef SMALL static off_t cat_fd(unsigned char * prepend, size_t count, off_t *gsizep, int fd) { char buf[BUFLEN]; off_t in_tot; ssize_t w; in_tot = count; w = write(STDOUT_FILENO, prepend, count); if (w == -1 || (size_t)w != count) { maybe_warn("write to stdout"); return -1; } for (;;) { ssize_t rv; rv = read(fd, buf, sizeof buf); if (rv == 0) break; if (rv < 0) { maybe_warn("read from fd %d", fd); break; } if (write(STDOUT_FILENO, buf, rv) != rv) { maybe_warn("write to stdout"); break; } in_tot += rv; } if (gsizep) *gsizep = in_tot; return (in_tot); } #endif static void handle_stdin(void) { unsigned char header1[4]; off_t usize, gsize; enum filetype method; ssize_t bytes_read; #ifndef NO_COMPRESS_SUPPORT FILE *in; #endif #ifndef SMALL if (fflag == 0 && lflag == 0 && isatty(STDIN_FILENO)) { maybe_warnx("standard input is a terminal -- ignoring"); return; } #endif if (lflag) { struct stat isb; /* XXX could read the whole file, etc. */ if (fstat(STDIN_FILENO, &isb) < 0) { maybe_warn("fstat"); return; } print_list(STDIN_FILENO, isb.st_size, "stdout", isb.st_mtime); return; } bytes_read = read_retry(STDIN_FILENO, header1, sizeof header1); if (bytes_read == -1) { maybe_warn("can't read stdin"); return; } else if (bytes_read != sizeof(header1)) { maybe_warnx("(stdin): unexpected end of file"); return; } method = file_gettype(header1); switch (method) { default: #ifndef SMALL if (fflag == 0) { maybe_warnx("unknown compression format"); return; } usize = cat_fd(header1, sizeof header1, &gsize, STDIN_FILENO); break; #endif case FT_GZIP: usize = gz_uncompress(STDIN_FILENO, STDOUT_FILENO, (char *)header1, sizeof header1, &gsize, "(stdin)"); break; #ifndef NO_BZIP2_SUPPORT case FT_BZIP2: usize = unbzip2(STDIN_FILENO, STDOUT_FILENO, (char *)header1, sizeof header1, &gsize); break; #endif #ifndef NO_COMPRESS_SUPPORT case FT_Z: if ((in = zdopen(STDIN_FILENO)) == NULL) { maybe_warnx("zopen of stdin"); return; } usize = zuncompress(in, stdout, (char *)header1, sizeof header1, &gsize); fclose(in); break; #endif #ifndef NO_PACK_SUPPORT case FT_PACK: usize = unpack(STDIN_FILENO, STDOUT_FILENO, (char *)header1, sizeof header1, &gsize); break; #endif #ifndef NO_XZ_SUPPORT case FT_XZ: usize = unxz(STDIN_FILENO, STDOUT_FILENO, (char *)header1, sizeof header1, &gsize); break; #endif } #ifndef SMALL if (vflag && !tflag && usize != -1 && gsize != -1) print_verbage(NULL, NULL, usize, gsize); if (vflag && tflag) print_test("(stdin)", usize != -1); #endif } static void handle_stdout(void) { off_t gsize, usize; struct stat sb; time_t systime; uint32_t mtime; int ret; #ifndef SMALL if (fflag == 0 && isatty(STDOUT_FILENO)) { maybe_warnx("standard output is a terminal -- ignoring"); return; } #endif /* If stdin is a file use its mtime, otherwise use current time */ ret = fstat(STDIN_FILENO, &sb); #ifndef SMALL if (ret < 0) { maybe_warn("Can't stat stdin"); return; } #endif if (S_ISREG(sb.st_mode)) mtime = (uint32_t)sb.st_mtime; else { systime = time(NULL); #ifndef SMALL if (systime == -1) { maybe_warn("time"); return; } #endif mtime = (uint32_t)systime; } usize = gz_compress(STDIN_FILENO, STDOUT_FILENO, &gsize, "", mtime); #ifndef SMALL if (vflag && !tflag && usize != -1 && gsize != -1) print_verbage(NULL, NULL, usize, gsize); #endif } /* do what is asked for, for the path name */ static void handle_pathname(char *path) { char *opath = path, *s = NULL; ssize_t len; int slen; struct stat sb; /* check for stdout/stdin */ if (path[0] == '-' && path[1] == '\0') { if (dflag) handle_stdin(); else handle_stdout(); return; } retry: if (stat(path, &sb) != 0) { /* lets try .gz if we're decompressing */ if (dflag && s == NULL && errno == ENOENT) { len = strlen(path); slen = suffixes[0].ziplen; s = malloc(len + slen + 1); if (s == NULL) maybe_err("malloc"); memcpy(s, path, len); memcpy(s + len, suffixes[0].zipped, slen + 1); path = s; goto retry; } maybe_warn("can't stat: %s", opath); goto out; } if (S_ISDIR(sb.st_mode)) { #ifndef SMALL if (rflag) handle_dir(path); else #endif maybe_warnx("%s is a directory", path); goto out; } if (S_ISREG(sb.st_mode)) handle_file(path, &sb); else maybe_warnx("%s is not a regular file", path); out: if (s) free(s); } /* compress/decompress a file */ static void handle_file(char *file, struct stat *sbp) { off_t usize, gsize; char outfile[PATH_MAX]; infile = file; if (dflag) { usize = file_uncompress(file, outfile, sizeof(outfile)); #ifndef SMALL if (vflag && tflag) print_test(file, usize != -1); #endif if (usize == -1) return; gsize = sbp->st_size; } else { gsize = file_compress(file, outfile, sizeof(outfile)); if (gsize == -1) return; usize = sbp->st_size; } #ifndef SMALL if (vflag && !tflag) print_verbage(file, (cflag) ? NULL : outfile, usize, gsize); #endif } #ifndef SMALL /* this is used with -r to recursively descend directories */ static void handle_dir(char *dir) { char *path_argv[2]; FTS *fts; FTSENT *entry; path_argv[0] = dir; path_argv[1] = 0; fts = fts_open(path_argv, FTS_PHYSICAL, NULL); if (fts == NULL) { warn("couldn't fts_open %s", dir); return; } while ((entry = fts_read(fts))) { switch(entry->fts_info) { case FTS_D: case FTS_DP: continue; case FTS_DNR: case FTS_ERR: case FTS_NS: maybe_warn("%s", entry->fts_path); continue; case FTS_F: handle_file(entry->fts_name, entry->fts_statp); } } (void)fts_close(fts); } #endif /* print a ratio - size reduction as a fraction of uncompressed size */ static void print_ratio(off_t in, off_t out, FILE *where) { int percent10; /* 10 * percent */ off_t diff; char buff[8]; int len; diff = in - out/2; if (diff <= 0) /* * Output is more than double size of input! print -99.9% * Quite possibly we've failed to get the original size. */ percent10 = -999; else { /* * We only need 12 bits of result from the final division, * so reduce the values until a 32bit division will suffice. */ while (in > 0x100000) { diff >>= 1; in >>= 1; } if (in != 0) percent10 = ((u_int)diff * 2000) / (u_int)in - 1000; else percent10 = 0; } len = snprintf(buff, sizeof buff, "%2.2d.", percent10); /* Move the '.' to before the last digit */ buff[len - 1] = buff[len - 2]; buff[len - 2] = '.'; fprintf(where, "%5s%%", buff); } #ifndef SMALL /* print compression statistics, and the new name (if there is one!) */ static void print_verbage(const char *file, const char *nfile, off_t usize, off_t gsize) { if (file) fprintf(stderr, "%s:%s ", file, strlen(file) < 7 ? "\t\t" : "\t"); print_ratio(usize, gsize, stderr); if (nfile) fprintf(stderr, " -- replaced with %s", nfile); fprintf(stderr, "\n"); fflush(stderr); } /* print test results */ static void print_test(const char *file, int ok) { if (exit_value == 0 && ok == 0) exit_value = 1; fprintf(stderr, "%s:%s %s\n", file, strlen(file) < 7 ? "\t\t" : "\t", ok ? "OK" : "NOT OK"); fflush(stderr); } #endif /* print a file's info ala --list */ /* eg: compressed uncompressed ratio uncompressed_name 354841 1679360 78.8% /usr/pkgsrc/distfiles/libglade-2.0.1.tar */ static void print_list(int fd, off_t out, const char *outfile, time_t ts) { static int first = 1; #ifndef SMALL static off_t in_tot, out_tot; uint32_t crc = 0; #endif off_t in = 0, rv; if (first) { #ifndef SMALL if (vflag) printf("method crc date time "); #endif if (qflag == 0) printf(" compressed uncompressed " "ratio uncompressed_name\n"); } first = 0; /* print totals? */ #ifndef SMALL if (fd == -1) { in = in_tot; out = out_tot; } else #endif { /* read the last 4 bytes - this is the uncompressed size */ rv = lseek(fd, (off_t)(-8), SEEK_END); if (rv != -1) { unsigned char buf[8]; uint32_t usize; rv = read(fd, (char *)buf, sizeof(buf)); if (rv == -1) maybe_warn("read of uncompressed size"); else if (rv != sizeof(buf)) maybe_warnx("read of uncompressed size"); else { usize = buf[4] | buf[5] << 8 | buf[6] << 16 | buf[7] << 24; in = (off_t)usize; #ifndef SMALL crc = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24; #endif } } } #ifndef SMALL if (vflag && fd == -1) printf(" "); else if (vflag) { char *date = ctime(&ts); /* skip the day, 1/100th second, and year */ date += 4; date[12] = 0; printf("%5s %08x %11s ", "defla"/*XXX*/, crc, date); } in_tot += in; out_tot += out; #endif printf("%12llu %12llu ", (unsigned long long)out, (unsigned long long)in); print_ratio(in, out, stdout); printf(" %s\n", outfile); } /* display the usage of NetBSD gzip */ static void usage(void) { fprintf(stderr, "%s\n", gzip_version); fprintf(stderr, "usage: %s [-" OPT_LIST "] [ [ ...]]\n" #ifndef SMALL " -1 --fast fastest (worst) compression\n" " -2 .. -8 set compression level\n" " -9 --best best (slowest) compression\n" " -c --stdout write to stdout, keep original files\n" " --to-stdout\n" " -d --decompress uncompress files\n" " --uncompress\n" " -f --force force overwriting & compress links\n" " -h --help display this help\n" " -k --keep don't delete input files during operation\n" " -l --list list compressed file contents\n" " -N --name save or restore original file name and time stamp\n" " -n --no-name don't save original file name or time stamp\n" " -q --quiet output no warnings\n" " -r --recursive recursively compress files in directories\n" " -S .suf use suffix .suf instead of .gz\n" " --suffix .suf\n" " -t --test test compressed file\n" " -V --version display program version\n" " -v --verbose print extra statistics\n", #else , #endif getprogname()); exit(0); } /* display the version of NetBSD gzip */ static void display_version(void) { fprintf(stderr, "%s\n", gzip_version); exit(0); } #ifndef NO_BZIP2_SUPPORT #include "unbzip2.c" #endif #ifndef NO_COMPRESS_SUPPORT #include "zuncompress.c" #endif #ifndef NO_PACK_SUPPORT #include "unpack.c" #endif #ifndef NO_XZ_SUPPORT #include "unxz.c" #endif static ssize_t read_retry(int fd, void *buf, size_t sz) { char *cp = buf; size_t left = MIN(sz, (size_t) SSIZE_MAX); while (left > 0) { ssize_t ret; ret = read(fd, cp, left); if (ret == -1) { return ret; } else if (ret == 0) { break; /* EOF */ } cp += ret; left -= ret; } return sz - left; }