From dba5a37b9d1388bfd642d5404da6fce6849c5b1f Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Mon, 24 Mar 2014 08:19:21 -0500 Subject: Most of the remaining cpio cleanup. --- toys/pending/cpio.c | 369 +++++++++++++++++++++++----------------------------- 1 file changed, 164 insertions(+), 205 deletions(-) (limited to 'toys') diff --git a/toys/pending/cpio.c b/toys/pending/cpio.c index 11ad4ea6..d1fd8a16 100644 --- a/toys/pending/cpio.c +++ b/toys/pending/cpio.c @@ -4,33 +4,30 @@ * same license as toybox or as CC0, at your option. * * http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/cpio.html + * and http://pubs.opengroup.org/onlinepubs/7908799/xcu/cpio.html * - * http://pubs.opengroup.org/onlinepubs/7908799/xcu/cpio.html - * (Yes, that's SUSv2, the newer standards removed it around the time RPM - * and initramfs started heavily using this archive format. Go figure.) + * Yes, that's SUSv2, the newer standards removed it around the time RPM + * and initramfs started heavily using this archive format. + * + * Modern cpio expanded header to 110 bytes (first field 6 bytes, rest are 8). + * In order: magic ino mode uid gid nlink mtime filesize devmajor devminor + * rdevmajor rdevminor namesize check -USE_CPIO(NEWTOY(cpio, "H:di|o|t|uF:[!iot][!dot][!uot]", TOYFLAG_BIN)) +USE_CPIO(NEWTOY(cpio, "duH:i|t|F:o|v(verbose)[!io][!ot]", TOYFLAG_BIN)) config CPIO bool "cpio" default n help - usage: cpio {-o|-t|-i[du]} [-H FMT] [-F ARCHIVE] + usage: cpio -{o|t|i} [-v] [--verbose] [-F FILE] [ignored: -du -H newc] copy files into and out of a "newc" format cpio archive - Actions: - -o create archive (stdin is a list of files, stdout is an archive) - -t list files (stdin is an archive, stdout is a list of files) - -i extract from archive into file system (stdin is an archive) - - Extract options: - -d create leading directories when extracting an archive - -u always overwrite files (default) - - Other options: - -H FMT archive format (ignored, only newc supported) - -F ARCHIVE read from or write to ARCHIVE file + -F FILE use archive FILE instead of stdin/stdout + -i extract from archive into file system (stdin=archive) + -o create archive (stdin=list of files, stdout=archive) + -t test files (list only, stdin=archive, stdout=list of files) + -v verbose (list files during create/extract) */ #define FOR_cpio @@ -39,213 +36,175 @@ config CPIO GLOBALS( char *archive; char *fmt; - - int outfd; ) -// 110 bytes -struct newc_header { - char c_magic[6]; - char c_ino[8]; - char c_mode[8]; - char c_uid[8]; - char c_gid[8]; - char c_nlink[8]; - char c_mtime[8]; - char c_filesize[8]; - char c_devmajor[8]; - char c_devminor[8]; - char c_rdevmajor[8]; - char c_rdevminor[8]; - char c_namesize[8]; - char c_check[8]; -}; - -void write_cpio_member(int fd, char *name, struct stat buf) +// Read strings, tail padded to 4 byte alignment. Argument "align" is amount +// by which start of string isn't aligned (usually 0). +static char *strpad(int fd, unsigned len, unsigned align) { - unsigned nlen = strlen(name)+1, error = 0, zero = 0; - ssize_t llen; + char *str; - if (!S_ISREG(buf.st_mode) && !S_ISLNK(buf.st_mode)) buf.st_size = 0; - else if (buf.st_size >> 32) { - perror_msg("skipping >2G file '%s'", name); - return; - } + align = (align + len) & 3; + if (align) len += (4-align); - llen = sprintf(toybuf, - "070701%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X", - (int)(buf.st_ino), buf.st_mode, buf.st_uid, buf.st_gid, (int)buf.st_nlink, - (int)(buf.st_mtime), (int)(buf.st_size), major(buf.st_dev), - minor(buf.st_dev), major(buf.st_rdev), minor(buf.st_rdev), nlen, 0); - xwrite(TT.outfd, toybuf, llen); - xwrite(TT.outfd, name, nlen); - - // NUL Pad header up to 4 multiple bytes. - llen = (llen + nlen) & 3; - if (llen) xwrite(TT.outfd, &zero, 4-llen); - - // Write out body for symlink or regular file - llen = buf.st_size; - if (S_ISLNK(buf.st_mode)) { - if (readlink(name, toybuf, sizeof(toybuf)-1) == llen) - xwrite(TT.outfd, toybuf, llen); - else perror_msg("readlink '%s'", name); - } else while (llen) { - nlen = llen > sizeof(toybuf) ? sizeof(toybuf) : llen; - // If read fails, write anyway (we already wrote size in the header). - if (nlen != readall(fd, toybuf, nlen)) - if (!error++) perror_msg("bad read from file '%s'", name); - xwrite(TT.outfd, toybuf, nlen); - } - llen = buf.st_size & 3; - if (nlen) write(TT.outfd, &zero, 4-llen); -} + xreadall(fd, str = xmalloc(len+1), len); + str[len]=0; // redundant, in case archive is bad -// Iterate through a list of files read from stdin. No users need rw. -void loopfiles_stdin(void) -{ - char *name = 0; - size_t size = 0; - - for (;;) { - struct stat st; - int len, fd; - - len = getline(&name, &size, stdin); - if (!name) break; - if (name[len-1] == '\n') name[--len] = 0; - if (lstat(name, &st) || (fd = open(name, O_RDONLY))<0) - perror_msg("%s", name); - else { - write_cpio_member(fd, name, st); - close(fd); - } - } - free(name); + return str; } //convert hex to uint; mostly to allow using bits of non-terminated strings -unsigned int htou(char * hex) +unsigned x8u(char *hex) { - unsigned int ret = 0, i = 0; - - for (;(i < 8 && hex[i]);) { - ret *= 16; - switch(hex[i]) { - case '0': - break; - case '1': - case '2': - case '3': - case '4': - case '5': - case '6': - case '7': - case '8': - case '9': - ret += hex[i] - '1' + 1; - break; - case 'A': - case 'B': - case 'C': - case 'D': - case 'E': - case 'F': - ret += hex[i] - 'A' + 10; - break; - } - i++; - } - return ret; -} + unsigned val, inpos = 8, outpos; + char pattern[6]; -// Read one cpio record. Returns 0 for last record, 1 for "continue". -int read_cpio_member(int fd, int how) -{ - uint32_t nsize, fsize; - mode_t mode = 0; - int pad, ofd = 0; - struct newc_header hdr; - char *name, *lastdir; - dev_t dev = 0; - - xreadall(fd, &hdr, sizeof(struct newc_header)); - nsize = htou(hdr.c_namesize); - xreadall(fd, name = xmalloc(nsize), nsize); - if (!strcmp("TRAILER!!!", name)) return 0; - fsize = htou(hdr.c_filesize); - mode += htou(hdr.c_mode); - pad = 4 - ((nsize + 2) % 4); // 2 == sizeof(struct newc_header) % 4 - if (pad < 4) xreadall(fd, toybuf, pad); - pad = 4 - (fsize % 4); - - if ((toys.optflags&FLAG_d) && (lastdir = strrchr(name, '/'))) - if (mkpathat(AT_FDCWD, name, 0, 2)) perror_msg("mkpath '%s'", name); - - if (how & 1) { - if (S_ISDIR(mode)) ofd = mkdir(name, mode); - else if (S_ISLNK(mode)) { - memset(toybuf, 0, sizeof(toybuf)); - if (fsize < sizeof(toybuf)) { - pad = readall(fd, toybuf, fsize); - if (pad < fsize) error_exit("short archive"); - pad = 4 - (fsize % 4); - fsize = 0; - if (symlink(toybuf, name)) { - perror_msg("could not write link %s", name); - toys.exitval |= 1; - } - } else { - perror_msg("link too long: %s", name); - toys.exitval |= 1; - } - } else if (S_ISBLK(mode)||S_ISCHR(mode)||S_ISFIFO(mode)||S_ISSOCK(mode)) { - dev = makedev(htou(hdr.c_rdevmajor),htou(hdr.c_rdevminor)); - ofd = mknod(name, mode, dev); - } else ofd = creat(name, mode); - if (ofd == -1) { - error_msg("could not create %s", name); - toys.exitval |= 1; - } + while (*hex == '0') { + hex++; + if (!--inpos) return 0; } - errno = 0; - if (how & 2) puts(name); - while (fsize) { - int i; - memset(toybuf, 0, sizeof(toybuf)); - i = readall(fd, toybuf, (fsize>sizeof(toybuf)) ? sizeof(toybuf) : fsize); - if (i < 1) error_exit("archive too short"); - if (ofd > 0) writeall(ofd, toybuf, i); - fsize -= i; - } - if (pad < 4) xreadall(fd, toybuf, pad); - return 1; -} + // Because scanf gratuitously treats %*X differently than printf does. + sprintf(pattern, "%%%dX%%n", inpos); + sscanf(hex, pattern, &val, &outpos); + if (inpos != outpos) error_exit("bad header"); -void read_cpio_archive(int fd, int how) -{ - for(;;) if (!read_cpio_member(fd, how)) return; + return val; } void cpio_main(void) { - TT.outfd = 1; + int afd; + // Subtle bit: FLAG_o is 1 so we can just use it to select stdin/stdout. + + afd = toys.optflags & FLAG_o; if (TT.archive) { - if (toys.optflags & (FLAG_i|FLAG_t)) { - xclose(0); - xopen(TT.archive, O_RDONLY); - } else if (toys.optflags & FLAG_o) { - xclose(1); - xcreate(TT.archive, O_CREAT|O_WRONLY|O_TRUNC, 0644); - } + int perm = (toys.optflags & FLAG_o) ? O_CREAT|O_WRONLY|O_TRUNC : O_RDONLY; + + afd = xcreate(TT.archive, perm, 0644); } - if (toys.optflags & FLAG_t) read_cpio_archive(0, 2); - else if (toys.optflags & FLAG_i) read_cpio_archive(0, 1); - else if (toys.optflags & FLAG_o) { - loopfiles_stdin(); - write(1, "07070100000000000000000000000000000000000000010000000000000000" - "000000000000000000000000000000000000000B00000000TRAILER!!!\0\0\0", 124); - } else error_exit("must use one of -iot"); + // read cpio archive + + if (toys.optflags & (FLAG_i|FLAG_t)) for (;;) { + char *name, *tofree, *data; + unsigned size, mode; + int test = toys.optflags & FLAG_t, err = 0; + + // Read header and name. + xreadall(afd, toybuf, 110); + tofree = name = strpad(afd, x8u(toybuf+94), 110); + if (!strcmp("TRAILER!!!", name)) break; + + // If you want to extract absolute paths, "cd /" and run cpio. + while (*name == '/') name++; + + // Align to 4 bytes. Note header is 110 bytes which is 2 bytes over. + + size = x8u(toybuf+54); + mode = x8u(toybuf+14); + + if (toys.optflags & (FLAG_t|FLAG_v)) puts(name); + + if (!test && strrchr(name, '/') && mkpathat(AT_FDCWD, name, 0, 2)) { + perror_msg("mkpath '%s'", name); + test++; + } + + // Consume entire record even if it couldn't create file, so we're + // properly aligned with next file. + + if (S_ISDIR(mode)) { + if (!test) err = mkdir(name, mode); + } else if (S_ISLNK(mode)) { + data = strpad(afd, size, 0); + if (!test) err = symlink(data, name); + } else if (S_ISREG(mode)) { + int fd; + + // If write fails, we still need to read/discard data to continue with + // archive. Since doing so overwrites errno, report error now + fd = test ? 0 : open(name, O_CREAT|O_WRONLY|O_TRUNC|O_NOFOLLOW, mode); + if (fd < 0) { + perror_msg("create %s", name); + test++; + } + + data = toybuf; + while (size) { + if (size < sizeof(toybuf)) data = strpad(afd, size, 0); + else xreadall(afd, toybuf, sizeof(toybuf)); + if (!test) xwrite(fd, data, data == toybuf ? sizeof(toybuf) : size); + if (data != toybuf) { + free(data); + break; + } + size -= sizeof(toybuf); + } + close(fd); + } else if (!test) + err = mknod(name, mode, makedev(x8u(toybuf+62), x8u(toybuf+70))); + + if (err<0) perror_msg("create '%s'", name); + free(tofree); + + // Output cpio archive + + } else { + char *name = 0; + size_t size = 0; + + for (;;) { + struct stat st; + unsigned nlen = strlen(name)+1, error = 0, zero = 0; + int len, fd; + ssize_t llen; + + len = getline(&name, &size, stdin); + if (len<1) break; + if (name[len-1] == '\n') name[--len] = 0; + if (lstat(name, &st) || (fd = open(name, O_RDONLY))<0) { + perror_msg("%s", name); + continue; + } + + if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode)) st.st_size = 0; + if (st.st_size >> 32) perror_msg("skipping >2G file '%s'", name); + else { + llen = sprintf(toybuf, + "070701%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X%08X", + (int)st.st_ino, st.st_mode, st.st_uid, st.st_gid, (int)st.st_nlink, + (int)st.st_mtime, (int)st.st_size, major(st.st_dev), + minor(st.st_dev), major(st.st_rdev), minor(st.st_rdev), nlen, 0); + xwrite(afd, toybuf, llen); + xwrite(afd, name, nlen); + + // NUL Pad header up to 4 multiple bytes. + llen = (llen + nlen) & 3; + if (llen) xwrite(afd, &zero, 4-llen); + + // Write out body for symlink or regular file + llen = st.st_size; + if (S_ISLNK(st.st_mode)) { + if (readlink(name, toybuf, sizeof(toybuf)-1) == llen) + xwrite(afd, toybuf, llen); + else perror_msg("readlink '%s'", name); + } else while (llen) { + nlen = llen > sizeof(toybuf) ? sizeof(toybuf) : llen; + // If read fails, write anyway (already wrote size in header) + if (nlen != readall(fd, toybuf, nlen)) + if (!error++) perror_msg("bad read from file '%s'", name); + xwrite(afd, toybuf, nlen); + } + llen = st.st_size & 3; + if (nlen) write(afd, &zero, 4-llen); + } + close(fd); + } + free(name); + + xwrite(afd, toybuf, + sprintf(toybuf, "070701%040X%056X%08XTRAILER!!!%c%c%c", + 1, 0x0b, 0, 0, 0, 0)); + } } -- cgit v1.2.3