From ebd54dbd6e481d31e80757f900ac8109ad1423c6 Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Sun, 10 Apr 2011 13:09:42 +0300 Subject: [PATCH] xz/DOS: Add experimental 8.3 filename support. This is incompatible with the 8.3 support patch made by Juan Manuel Guerrero. I think this one is nicer, but I need to get feedback from DOS users before saying that this is the final version of 8.3 filename support. --- src/xz/suffix.c | 176 +++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 167 insertions(+), 9 deletions(-) diff --git a/src/xz/suffix.c b/src/xz/suffix.c index c89f67fe..e5156261 100644 --- a/src/xz/suffix.c +++ b/src/xz/suffix.c @@ -12,6 +12,10 @@ #include "private.h" +#ifdef __DJGPP__ +# include +#endif + // For case-insensitive filename suffix on case-insensitive systems #if defined(TUKLIB_DOSLIKE) || defined(__VMS) # define strcmp strcasecmp @@ -45,6 +49,31 @@ has_dir_sep(const char *str) } +#ifdef __DJGPP__ +/// \brief Test for special suffix used for 8.3 short filenames (SFN) +/// +/// \return If str matches *.?- or *.??-, true is returned. Otherwise +/// false is returned. +static bool +has_sfn_suffix(const char *str, size_t len) +{ + if (len >= 4 && str[len - 1] == '-' && str[len - 2] != '.' + && !is_dir_sep(str[len - 2])) { + // *.?- + if (str[len - 3] == '.') + return !is_dir_sep(str[len - 4]); + + // *.??- + if (len >= 5 && !is_dir_sep(str[len - 3]) + && str[len - 4] == '.') + return !is_dir_sep(str[len - 5]); + } + + return false; +} +#endif + + /// \brief Checks if src_name has given compressed_suffix /// /// \param suffix Filename suffix to look for @@ -87,6 +116,9 @@ uncompressed_name(const char *src_name, const size_t src_len) { ".xz", "" }, { ".txz", ".tar" }, // .txz abbreviation for .txt.gz is rare. { ".lzma", "" }, +#ifdef __DJGPP__ + { ".lzm", "" }, +#endif { ".tlz", ".tar" }, // { ".gz", "" }, // { ".tgz", ".tar" }, @@ -112,6 +144,17 @@ uncompressed_name(const char *src_name, const size_t src_len) break; } } + +#ifdef __DJGPP__ + // Support also *.?- -> *.? and *.??- -> *.?? on DOS. + // This is done also when long filenames are available + // to keep it easy to decompress files created when + // long filename support wasn't available. + if (new_len == 0 && has_sfn_suffix(src_name, src_len)) { + new_suffix = ""; + new_len = src_len - 1; + } +#endif } if (new_len == 0 && custom_suffix != NULL) @@ -134,21 +177,35 @@ uncompressed_name(const char *src_name, const size_t src_len) } +/// This message is needed in multiple places in compressed_name(), +/// so the message has been put into its own function. +static void +msg_suffix(const char *src_name, const char *suffix) +{ + message_warning(_("%s: File already has `%s' suffix, skipping"), + src_name, suffix); + return; +} + + /// \brief Appends suffix to src_name /// /// In contrast to uncompressed_name(), we check only suffixes that are valid /// for the specified file format. static char * -compressed_name(const char *src_name, const size_t src_len) +compressed_name(const char *src_name, size_t src_len) { // The order of these must match the order in args.h. - static const char *const all_suffixes[][3] = { + static const char *const all_suffixes[][4] = { { ".xz", ".txz", NULL }, { ".lzma", +#ifdef __DJGPP__ + ".lzm", +#endif ".tlz", NULL /* @@ -170,20 +227,27 @@ compressed_name(const char *src_name, const size_t src_len) const size_t format = opt_format - 1; const char *const *suffixes = all_suffixes[format]; + // Look for known filename suffixes and refuse to compress them. for (size_t i = 0; suffixes[i] != NULL; ++i) { if (test_suffix(suffixes[i], src_name, src_len) != 0) { - message_warning(_("%s: File already has `%s' " - "suffix, skipping"), src_name, - suffixes[i]); + msg_suffix(src_name, suffixes[i]); return NULL; } } +#ifdef __DJGPP__ + // Recognize also the special suffix that is used when long + // filename (LFN) support isn't available. This suffix is + // recognized on LFN systems too. + if (opt_format == FORMAT_XZ && has_sfn_suffix(src_name, src_len)) { + msg_suffix(src_name, "-"); + return NULL; + } +#endif + if (custom_suffix != NULL) { if (test_suffix(custom_suffix, src_name, src_len) != 0) { - message_warning(_("%s: File already has `%s' " - "suffix, skipping"), src_name, - custom_suffix); + msg_suffix(src_name, custom_suffix); return NULL; } } @@ -199,7 +263,101 @@ compressed_name(const char *src_name, const size_t src_len) const char *suffix = custom_suffix != NULL ? custom_suffix : suffixes[0]; - const size_t suffix_len = strlen(suffix); + size_t suffix_len = strlen(suffix); + +#ifdef __DJGPP__ + if (!_use_lfn(src_name)) { + // Long filename (LFN) support isn't available and we are + // limited to 8.3 short filenames (SFN). + // + // Look for suffix separator from the filename, and make sure + // that it is in the filename, not in a directory name. + const char *sufsep = strrchr(src_name, '.'); + if (sufsep == NULL || sufsep[1] == '\0' + || has_dir_sep(sufsep)) { + // src_name has no filename extension. + // + // Examples: + // xz foo -> foo.xz + // xz -F lzma foo -> foo.lzm + // xz -S x foo -> foox + // xz -S x foo. -> foo.x + // xz -S x.y foo -> foox.y + // xz -S .x foo -> foo.x + // xz -S .x foo. -> foo.x + // + // Avoid double dots: + if (sufsep != NULL && sufsep[1] == '\0' + && suffix[0] == '.') + --src_len; + + } else if (custom_suffix == NULL + && strcasecmp(sufsep, ".tar") == 0) { + // ".tar" is handled specially. + // + // Examples: + // xz foo.tar -> foo.txz + // xz -F lzma foo.tar -> foo.tlz + static const char *const tar_suffixes[] = { + ".txz", + ".tlz", + // ".tgz", + }; + suffix = tar_suffixes[format]; + suffix_len = 4; + src_len -= 4; + + } else { + if (custom_suffix == NULL && opt_format == FORMAT_XZ) { + // Instead of the .xz suffix, use a single + // character at the end of the filename + // extension. This is to minimize name + // conflicts when compressing multiple files + // with the same basename. E.g. foo.txt and + // foo.exe become foo.tx- and foo.ex-. Dash + // is rare as the last character of the + // filename extension, so it seems to be + // quite safe choice and it stands out better + // in directory listings than e.g. x. For + // comparison, gzip uses z. + suffix = "-"; + suffix_len = 1; + } + + if (suffix[0] == '.') { + // The first character of the suffix is a dot. + // Throw away the original filename extension + // and replace it with the new suffix. + // + // Examples: + // xz -F lzma foo.txt -> foo.lzm + // xz -S .x foo.txt -> foo.x + src_len = sufsep - src_name; + + } else { + // The first character of the suffix is not + // a dot. Preserve the first 0-2 characters + // of the original filename extension. + // + // Examples: + // xz foo.txt -> foo.tx- + // xz -S x foo.c -> foo.cx + // xz -S ab foo.c -> foo.cab + // xz -S ab foo.txt -> foo.tab + // xz -S abc foo.txt -> foo.abc + // + // Truncate the suffix to three chars: + if (suffix_len > 3) + suffix_len = 3; + + // If needed, overwrite 1-3 characters. + if (strlen(sufsep) > 4 - suffix_len) + src_len = sufsep - src_name + + 4 - suffix_len; + } + } + } +#endif char *dest_name = xmalloc(src_len + suffix_len + 1);