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Diffstat (limited to 'contrib/libarchive/tar/util.c')
| -rw-r--r-- | contrib/libarchive/tar/util.c | 559 |
1 files changed, 559 insertions, 0 deletions
diff --git a/contrib/libarchive/tar/util.c b/contrib/libarchive/tar/util.c new file mode 100644 index 0000000..f723274 --- /dev/null +++ b/contrib/libarchive/tar/util.c @@ -0,0 +1,559 @@ +/*- + * Copyright (c) 2003-2007 Tim Kientzle + * 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(S) ``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(S) 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 "bsdtar_platform.h" +__FBSDID("$FreeBSD: src/usr.bin/tar/util.c,v 1.23 2008/12/15 06:00:25 kientzle Exp $"); + +#ifdef HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#ifdef HAVE_SYS_TYPES_H +#include <sys/types.h> /* Linux doesn't define mode_t, etc. in sys/stat.h. */ +#endif +#include <ctype.h> +#ifdef HAVE_ERRNO_H +#include <errno.h> +#endif +#ifdef HAVE_IO_H +#include <io.h> +#endif +#ifdef HAVE_STDARG_H +#include <stdarg.h> +#endif +#ifdef HAVE_STDINT_H +#include <stdint.h> +#endif +#include <stdio.h> +#ifdef HAVE_STDLIB_H +#include <stdlib.h> +#endif +#ifdef HAVE_STRING_H +#include <string.h> +#endif +#ifdef HAVE_WCTYPE_H +#include <wctype.h> +#else +/* If we don't have wctype, we need to hack up some version of iswprint(). */ +#define iswprint isprint +#endif + +#include "bsdtar.h" +#include "err.h" + +static size_t bsdtar_expand_char(char *, size_t, char); +static const char *strip_components(const char *path, int elements); + +#if defined(_WIN32) && !defined(__CYGWIN__) +#define read _read +#endif + +/* TODO: Hack up a version of mbtowc for platforms with no wide + * character support at all. I think the following might suffice, + * but it needs careful testing. + * #if !HAVE_MBTOWC + * #define mbtowc(wcp, p, n) ((*wcp = *p), 1) + * #endif + */ + +/* + * Print a string, taking care with any non-printable characters. + * + * Note that we use a stack-allocated buffer to receive the formatted + * string if we can. This is partly performance (avoiding a call to + * malloc()), partly out of expedience (we have to call vsnprintf() + * before malloc() anyway to find out how big a buffer we need; we may + * as well point that first call at a small local buffer in case it + * works), but mostly for safety (so we can use this to print messages + * about out-of-memory conditions). + */ + +void +safe_fprintf(FILE *f, const char *fmt, ...) +{ + char fmtbuff_stack[256]; /* Place to format the printf() string. */ + char outbuff[256]; /* Buffer for outgoing characters. */ + char *fmtbuff_heap; /* If fmtbuff_stack is too small, we use malloc */ + char *fmtbuff; /* Pointer to fmtbuff_stack or fmtbuff_heap. */ + int fmtbuff_length; + int length, n; + va_list ap; + const char *p; + unsigned i; + wchar_t wc; + char try_wc; + + /* Use a stack-allocated buffer if we can, for speed and safety. */ + fmtbuff_heap = NULL; + fmtbuff_length = sizeof(fmtbuff_stack); + fmtbuff = fmtbuff_stack; + + /* Try formatting into the stack buffer. */ + va_start(ap, fmt); + length = vsnprintf(fmtbuff, fmtbuff_length, fmt, ap); + va_end(ap); + + /* If the result was too large, allocate a buffer on the heap. */ + if (length >= fmtbuff_length) { + fmtbuff_length = length+1; + fmtbuff_heap = malloc(fmtbuff_length); + + /* Reformat the result into the heap buffer if we can. */ + if (fmtbuff_heap != NULL) { + fmtbuff = fmtbuff_heap; + va_start(ap, fmt); + length = vsnprintf(fmtbuff, fmtbuff_length, fmt, ap); + va_end(ap); + } else { + /* Leave fmtbuff pointing to the truncated + * string in fmtbuff_stack. */ + length = sizeof(fmtbuff_stack) - 1; + } + } + + /* Note: mbrtowc() has a cleaner API, but mbtowc() seems a bit + * more portable, so we use that here instead. */ + n = mbtowc(NULL, NULL, 1); /* Reset the shift state. */ + + /* Write data, expanding unprintable characters. */ + p = fmtbuff; + i = 0; + try_wc = 1; + while (*p != '\0') { + + /* Convert to wide char, test if the wide + * char is printable in the current locale. */ + if (try_wc && (n = mbtowc(&wc, p, length)) != -1) { + length -= n; + if (iswprint(wc) && wc != L'\\') { + /* Printable, copy the bytes through. */ + while (n-- > 0) + outbuff[i++] = *p++; + } else { + /* Not printable, format the bytes. */ + while (n-- > 0) + i += (unsigned)bsdtar_expand_char( + outbuff, i, *p++); + } + } else { + /* After any conversion failure, don't bother + * trying to convert the rest. */ + i += (unsigned)bsdtar_expand_char(outbuff, i, *p++); + try_wc = 0; + } + + /* If our output buffer is full, dump it and keep going. */ + if (i > (sizeof(outbuff) - 20)) { + outbuff[i] = '\0'; + fprintf(f, "%s", outbuff); + i = 0; + } + } + outbuff[i] = '\0'; + fprintf(f, "%s", outbuff); + + /* If we allocated a heap-based formatting buffer, free it now. */ + if (fmtbuff_heap != NULL) + free(fmtbuff_heap); +} + +/* + * Render an arbitrary sequence of bytes into printable ASCII characters. + */ +static size_t +bsdtar_expand_char(char *buff, size_t offset, char c) +{ + size_t i = offset; + + if (isprint((unsigned char)c) && c != '\\') + buff[i++] = c; + else { + buff[i++] = '\\'; + switch (c) { + case '\a': buff[i++] = 'a'; break; + case '\b': buff[i++] = 'b'; break; + case '\f': buff[i++] = 'f'; break; + case '\n': buff[i++] = 'n'; break; +#if '\r' != '\n' + /* On some platforms, \n and \r are the same. */ + case '\r': buff[i++] = 'r'; break; +#endif + case '\t': buff[i++] = 't'; break; + case '\v': buff[i++] = 'v'; break; + case '\\': buff[i++] = '\\'; break; + default: + sprintf(buff + i, "%03o", 0xFF & (int)c); + i += 3; + } + } + + return (i - offset); +} + +int +yes(const char *fmt, ...) +{ + char buff[32]; + char *p; + ssize_t l; + + va_list ap; + va_start(ap, fmt); + vfprintf(stderr, fmt, ap); + va_end(ap); + fprintf(stderr, " (y/N)? "); + fflush(stderr); + + l = read(2, buff, sizeof(buff) - 1); + if (l <= 0) + return (0); + buff[l] = 0; + + for (p = buff; *p != '\0'; p++) { + if (isspace((unsigned char)*p)) + continue; + switch(*p) { + case 'y': case 'Y': + return (1); + case 'n': case 'N': + return (0); + default: + return (0); + } + } + + return (0); +} + +/*- + * The logic here for -C <dir> attempts to avoid + * chdir() as long as possible. For example: + * "-C /foo -C /bar file" needs chdir("/bar") but not chdir("/foo") + * "-C /foo -C bar file" needs chdir("/foo/bar") + * "-C /foo -C bar /file1" does not need chdir() + * "-C /foo -C bar /file1 file2" needs chdir("/foo/bar") before file2 + * + * The only correct way to handle this is to record a "pending" chdir + * request and combine multiple requests intelligently until we + * need to process a non-absolute file. set_chdir() adds the new dir + * to the pending list; do_chdir() actually executes any pending chdir. + * + * This way, programs that build tar command lines don't have to worry + * about -C with non-existent directories; such requests will only + * fail if the directory must be accessed. + * + * TODO: Make this handle Windows paths correctly. + */ +void +set_chdir(struct bsdtar *bsdtar, const char *newdir) +{ + if (newdir[0] == '/') { + /* The -C /foo -C /bar case; dump first one. */ + free(bsdtar->pending_chdir); + bsdtar->pending_chdir = NULL; + } + if (bsdtar->pending_chdir == NULL) + /* Easy case: no previously-saved dir. */ + bsdtar->pending_chdir = strdup(newdir); + else { + /* The -C /foo -C bar case; concatenate */ + char *old_pending = bsdtar->pending_chdir; + size_t old_len = strlen(old_pending); + bsdtar->pending_chdir = malloc(old_len + strlen(newdir) + 2); + if (old_pending[old_len - 1] == '/') + old_pending[old_len - 1] = '\0'; + if (bsdtar->pending_chdir != NULL) + sprintf(bsdtar->pending_chdir, "%s/%s", + old_pending, newdir); + free(old_pending); + } + if (bsdtar->pending_chdir == NULL) + lafe_errc(1, errno, "No memory"); +} + +void +do_chdir(struct bsdtar *bsdtar) +{ + if (bsdtar->pending_chdir == NULL) + return; + + if (chdir(bsdtar->pending_chdir) != 0) { + lafe_errc(1, 0, "could not chdir to '%s'\n", + bsdtar->pending_chdir); + } + free(bsdtar->pending_chdir); + bsdtar->pending_chdir = NULL; +} + +static const char * +strip_components(const char *p, int elements) +{ + /* Skip as many elements as necessary. */ + while (elements > 0) { + switch (*p++) { + case '/': +#if defined(_WIN32) && !defined(__CYGWIN__) + case '\\': /* Support \ path sep on Windows ONLY. */ +#endif + elements--; + break; + case '\0': + /* Path is too short, skip it. */ + return (NULL); + } + } + + /* Skip any / characters. This handles short paths that have + * additional / termination. This also handles the case where + * the logic above stops in the middle of a duplicate // + * sequence (which would otherwise get converted to an + * absolute path). */ + for (;;) { + switch (*p) { + case '/': +#if defined(_WIN32) && !defined(__CYGWIN__) + case '\\': /* Support \ path sep on Windows ONLY. */ +#endif + ++p; + break; + case '\0': + return (NULL); + default: + return (p); + } + } +} + +/* + * Handle --strip-components and any future path-rewriting options. + * Returns non-zero if the pathname should not be extracted. + * + * TODO: Support pax-style regex path rewrites. + */ +int +edit_pathname(struct bsdtar *bsdtar, struct archive_entry *entry) +{ + const char *name = archive_entry_pathname(entry); +#if HAVE_REGEX_H + char *subst_name; + int r; +#endif + +#if HAVE_REGEX_H + r = apply_substitution(bsdtar, name, &subst_name, 0); + if (r == -1) { + lafe_warnc(0, "Invalid substitution, skipping entry"); + return 1; + } + if (r == 1) { + archive_entry_copy_pathname(entry, subst_name); + if (*subst_name == '\0') { + free(subst_name); + return -1; + } else + free(subst_name); + name = archive_entry_pathname(entry); + } + + if (archive_entry_hardlink(entry)) { + r = apply_substitution(bsdtar, archive_entry_hardlink(entry), &subst_name, 1); + if (r == -1) { + lafe_warnc(0, "Invalid substitution, skipping entry"); + return 1; + } + if (r == 1) { + archive_entry_copy_hardlink(entry, subst_name); + free(subst_name); + } + } + if (archive_entry_symlink(entry) != NULL) { + r = apply_substitution(bsdtar, archive_entry_symlink(entry), &subst_name, 1); + if (r == -1) { + lafe_warnc(0, "Invalid substitution, skipping entry"); + return 1; + } + if (r == 1) { + archive_entry_copy_symlink(entry, subst_name); + free(subst_name); + } + } +#endif + + /* Strip leading dir names as per --strip-components option. */ + if (bsdtar->strip_components > 0) { + const char *linkname = archive_entry_hardlink(entry); + + name = strip_components(name, bsdtar->strip_components); + if (name == NULL) + return (1); + + if (linkname != NULL) { + linkname = strip_components(linkname, + bsdtar->strip_components); + if (linkname == NULL) + return (1); + archive_entry_copy_hardlink(entry, linkname); + } + } + + /* By default, don't write or restore absolute pathnames. */ + if (!bsdtar->option_absolute_paths) { + const char *rp, *p = name; + int slashonly = 1; + + /* Remove leading "//./" or "//?/" or "//?/UNC/" + * (absolute path prefixes used by Windows API) */ + if ((p[0] == '/' || p[0] == '\\') && + (p[1] == '/' || p[1] == '\\') && + (p[2] == '.' || p[2] == '?') && + (p[3] == '/' || p[3] == '\\')) + { + if (p[2] == '?' && + (p[4] == 'U' || p[4] == 'u') && + (p[5] == 'N' || p[5] == 'n') && + (p[6] == 'C' || p[6] == 'c') && + (p[7] == '/' || p[7] == '\\')) + p += 8; + else + p += 4; + slashonly = 0; + } + do { + rp = p; + /* Remove leading drive letter from archives created + * on Windows. */ + if (((p[0] >= 'a' && p[0] <= 'z') || + (p[0] >= 'A' && p[0] <= 'Z')) && + p[1] == ':') { + p += 2; + slashonly = 0; + } + /* Remove leading "/../", "//", etc. */ + while (p[0] == '/' || p[0] == '\\') { + if (p[1] == '.' && p[2] == '.' && + (p[3] == '/' || p[3] == '\\')) { + p += 3; /* Remove "/..", leave "/" + * for next pass. */ + slashonly = 0; + } else + p += 1; /* Remove "/". */ + } + } while (rp != p); + + if (p != name && !bsdtar->warned_lead_slash) { + /* Generate a warning the first time this happens. */ + if (slashonly) + lafe_warnc(0, + "Removing leading '%c' from member names", + name[0]); + else + lafe_warnc(0, + "Removing leading drive letter from " + "member names"); + bsdtar->warned_lead_slash = 1; + } + + /* Special case: Stripping everything yields ".". */ + if (*p == '\0') + name = "."; + else + name = p; + } else { + /* Strip redundant leading '/' characters. */ + while (name[0] == '/' && name[1] == '/') + name++; + } + + /* Safely replace name in archive_entry. */ + if (name != archive_entry_pathname(entry)) { + char *q = strdup(name); + archive_entry_copy_pathname(entry, q); + free(q); + } + return (0); +} + +/* + * It would be nice to just use printf() for formatting large numbers, + * but the compatibility problems are quite a headache. Hence the + * following simple utility function. + */ +const char * +tar_i64toa(int64_t n0) +{ + static char buff[24]; + int64_t n = n0 < 0 ? -n0 : n0; + char *p = buff + sizeof(buff); + + *--p = '\0'; + do { + *--p = '0' + (int)(n % 10); + n /= 10; + } while (n > 0); + if (n0 < 0) + *--p = '-'; + return p; +} + +/* + * Like strcmp(), but try to be a little more aware of the fact that + * we're comparing two paths. Right now, it just handles leading + * "./" and trailing '/' specially, so that "a/b/" == "./a/b" + * + * TODO: Make this better, so that "./a//b/./c/" == "a/b/c" + * TODO: After this works, push it down into libarchive. + * TODO: Publish the path normalization routines in libarchive so + * that bsdtar can normalize paths and use fast strcmp() instead + * of this. + * + * Note: This is currently only used within write.c, so should + * not handle \ path separators. + */ + +int +pathcmp(const char *a, const char *b) +{ + /* Skip leading './' */ + if (a[0] == '.' && a[1] == '/' && a[2] != '\0') + a += 2; + if (b[0] == '.' && b[1] == '/' && b[2] != '\0') + b += 2; + /* Find the first difference, or return (0) if none. */ + while (*a == *b) { + if (*a == '\0') + return (0); + a++; + b++; + } + /* + * If one ends in '/' and the other one doesn't, + * they're the same. + */ + if (a[0] == '/' && a[1] == '\0' && b[0] == '\0') + return (0); + if (a[0] == '\0' && b[0] == '/' && b[1] == '\0') + return (0); + /* They're really different, return the correct sign. */ + return (*(const unsigned char *)a - *(const unsigned char *)b); +} |
