From 23fff2bc6a8a379faf742998e9042269d6b6bb89 Mon Sep 17 00:00:00 2001 From: Christian Brabandt Date: Wed, 27 Sep 2023 20:37:44 +0200 Subject: [PATCH] Add extended attribute support (Linux) It's been a long standing issue, that if you write a file with extended attributes and backupcopy=no, the file will loose the extended attributes. So this patch adds support for retrieving the extended attributes and copying it to the new file. It currently only works on linux, mainly I don't know the different APIs for other systems (BSD, MacOSX and Solaris). On linux, this should be supported since Kernel 2.4 or something, so this should be pretty safe to use now. I think it makes sense to have this enabled in normal builds so it is not so surprising if one loses those attributes, but not sure. I also added it explicitly to the :version output as well as make it able to check using `:echo has("xattr")`, to have users easily check that this is available. In contrast to the similar support for SELINUX and SMACK support (which also internally uses extended attributes), I have made this a FEAT_XATTR define, instead of the similar HAVE_XATTR, but that should just be a implementation detail (but happy to change if wanted). todo: [X] try to write tests. fixes: #306 Signed-off-by: Christian Brabandt --- .github/workflows/ci.yml | 2 + runtime/doc/builtin.txt | 4 +- runtime/doc/editing.txt | 9 +++- runtime/doc/tags | 6 +++ runtime/doc/various.txt | 3 +- src/auto/configure | 28 ++++++++++ src/bufwrite.c | 15 +++++- src/config.h.in | 1 + src/configure.ac | 12 +++++ src/errors.h | 10 +++- src/evalfunc.c | 7 +++ src/feature.h | 10 +++- src/os_unix.c | 95 ++++++++++++++++++++++++++++++++++ src/proto/os_unix.pro | 1 + src/testdir/test_writefile.vim | 23 ++++++++ src/version.c | 5 ++ 16 files changed, 225 insertions(+), 6 deletions(-) diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml index 8c2e5396b7c680..cd1615f9f447fe 100644 --- a/.github/workflows/ci.yml +++ b/.github/workflows/ci.yml @@ -110,6 +110,8 @@ jobs: tcl-dev \ cscope \ libsodium-dev \ + attr \ + libattr1-dev ) fi sudo apt-get update && sudo apt-get install -y "${PKGS[@]}" diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt index 8a92ff6ecfe1c2..b4ea216f31e804 100644 --- a/runtime/doc/builtin.txt +++ b/runtime/doc/builtin.txt @@ -1,4 +1,4 @@ -*builtin.txt* For Vim version 9.0. Last change: 2023 Aug 09 +*builtin.txt* For Vim version 9.0. Last change: 2023 Sep 27 VIM REFERENCE MANUAL by Bram Moolenaar @@ -11082,6 +11082,8 @@ winaltkeys Compiled with 'winaltkeys' option. windows Compiled with support for more than one window. (always true) writebackup Compiled with 'writebackup' default on. +xattr Compiled with extended attributes support |xattr| + (currently only supported on Linux). xfontset Compiled with X fontset support |xfontset|. xim Compiled with X input method support |xim|. xpm Compiled with pixmap support. diff --git a/runtime/doc/editing.txt b/runtime/doc/editing.txt index 46279110a7238c..a015c8462aaf9c 100644 --- a/runtime/doc/editing.txt +++ b/runtime/doc/editing.txt @@ -1,4 +1,4 @@ -*editing.txt* For Vim version 9.0. Last change: 2023 Sep 22 +*editing.txt* For Vim version 9.0. Last change: 2023 Sep 27 VIM REFERENCE MANUAL by Bram Moolenaar @@ -1097,6 +1097,13 @@ will get the ACL info of the original file. The ACL info is also used to check if a file is read-only (when opening the file). + *xattr* *E1506* *E1507* *E1508* *E1509* +xattr stands for Extended Attributes It is an advanced way to save metadata +alongside the file in the filesystem. It depends on the actual filesystem +being used and Vim supports it only on a Linux system. + Vim attempts to preserve the extended attribute info when writing a file. +The backup file will get the extended attribute of the original file. + *read-only-share* When MS-Windows shares a drive on the network it can be marked as read-only. This means that even if the file read-only attribute is absent, and the ACL diff --git a/runtime/doc/tags b/runtime/doc/tags index 1df34d3a3d5a55..249800fd292892 100644 --- a/runtime/doc/tags +++ b/runtime/doc/tags @@ -1483,6 +1483,7 @@ $quote eval.txt /*$quote* +wildmenu various.txt /*+wildmenu* +windows various.txt /*+windows* +writebackup various.txt /*+writebackup* ++xattr various.txt /*+xattr* +xfontset various.txt /*+xfontset* +xim various.txt /*+xim* +xpm various.txt /*+xpm* @@ -4506,6 +4507,10 @@ E1502 builtin.txt /*E1502* E1503 builtin.txt /*E1503* E1504 builtin.txt /*E1504* E1505 builtin.txt /*E1505* +E1506 editing.txt /*E1506* +E1507 editing.txt /*E1507* +E1508 editing.txt /*E1508* +E1509 editing.txt /*E1509* E151 helphelp.txt /*E151* E152 helphelp.txt /*E152* E153 helphelp.txt /*E153* @@ -11224,6 +11229,7 @@ x-resources version5.txt /*x-resources* x11-clientserver remote.txt /*x11-clientserver* x11-cut-buffer gui_x11.txt /*x11-cut-buffer* x11-selection gui_x11.txt /*x11-selection* +xattr editing.txt /*xattr* xf86conf.vim syntax.txt /*xf86conf.vim* xfontset mbyte.txt /*xfontset* xfree-xterm syntax.txt /*xfree-xterm* diff --git a/runtime/doc/various.txt b/runtime/doc/various.txt index e478c8266ea6a3..b2b79039358f5b 100644 --- a/runtime/doc/various.txt +++ b/runtime/doc/various.txt @@ -1,4 +1,4 @@ -*various.txt* For Vim version 9.0. Last change: 2022 Dec 13 +*various.txt* For Vim version 9.0. Last change: 2023 Sep 27 VIM REFERENCE MANUAL by Bram Moolenaar @@ -503,6 +503,7 @@ T *+windows* more than one window; Always enabled since 8.0.1118. m *+writebackup* |'writebackup'| is default on m *+xim* X input method |xim| *+xfontset* X fontset support |xfontset| +N *+xattr* compiled with extended attribute support (Linux only) *+xpm* pixmap support m *+xpm_w32* Win32 GUI only: pixmap support |w32-xpm-support| *+xsmp* XSMP (X session management) support diff --git a/src/auto/configure b/src/auto/configure index 34e9f449aa60c1..54c1aa8159944f 100755 --- a/src/auto/configure +++ b/src/auto/configure @@ -825,6 +825,7 @@ with_global_runtime with_modified_by enable_smack enable_selinux +enable_xattr with_features with_compiledby enable_xsmp @@ -1514,6 +1515,7 @@ Optional Features: --disable-darwin Disable Darwin (Mac OS X) support. --disable-smack Do not check for Smack support. --disable-selinux Do not check for SELinux support. + --disable-xattr Do not check for XATTR support. --disable-xsmp Disable XSMP session management --disable-xsmp-interact Disable XSMP interaction --enable-luainterp=OPTS Include Lua interpreter. default=no OPTS=no/yes/dynamic @@ -5419,6 +5421,32 @@ printf "%s\n" "yes" >&6; } fi fi +{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking --enable-xattr argument" >&5 +printf %s "checking --enable-xattr argument... " >&6; } +# Check whether --enable-xattr was given. +if test ${enable_xattr+y} +then : + enableval=$enable_xattr; +else $as_nop + enable_xattr="yes" +fi + +if test "$enable_xattr" = "yes"; then + { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5 +printf "%s\n" "yes" >&6; } + ac_fn_c_check_header_compile "$LINENO" "attr/xattr.h" "ac_cv_header_attr_xattr_h" "$ac_includes_default" +if test "x$ac_cv_header_attr_xattr_h" = xyes +then : + printf "%s\n" "#define HAVE_XATTR 1" >>confdefs.h + +fi + +else + { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5 +printf "%s\n" "no" >&6; } +fi + + { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking --with-features argument" >&5 printf %s "checking --with-features argument... " >&6; } diff --git a/src/bufwrite.c b/src/bufwrite.c index 03a83b569a44fa..bf79ad5bf3fcb2 100644 --- a/src/bufwrite.c +++ b/src/bufwrite.c @@ -1471,6 +1471,9 @@ buf_write( # if defined(HAVE_SELINUX) || defined(HAVE_SMACK) mch_copy_sec(fname, backup); # endif +# ifdef FEAT_XATTR + mch_copy_xattr(fname, backup); +# endif #endif // copy the file. @@ -1506,6 +1509,9 @@ buf_write( #if defined(HAVE_SELINUX) || defined(HAVE_SMACK) mch_copy_sec(fname, backup); #endif +#ifdef FEAT_XATTR + mch_copy_xattr(fname, backup); +#endif #ifdef MSWIN (void)mch_copy_file_attribute(fname, backup); #endif @@ -2196,11 +2202,18 @@ buf_write( } #endif -#if defined(HAVE_SELINUX) || defined(HAVE_SMACK) +#if defined(HAVE_SELINUX) || defined(HAVE_SMACK) || defined(FEAT_XATTR) // Probably need to set the security context. if (!backup_copy) + { +#if defined(HAVE_SELINUX) || defined(HAVE_SMACK) mch_copy_sec(backup, wfname); #endif +#ifdef FEAT_XATTR + mch_copy_xattr(backup, wfname); +#endif + } +#endif #ifdef UNIX // When creating a new file, set its owner/group to that of the diff --git a/src/config.h.in b/src/config.h.in index 93972ca0cc723a..8ad9f03136ea60 100644 --- a/src/config.h.in +++ b/src/config.h.in @@ -226,6 +226,7 @@ #undef HAVE_MBLEN #undef HAVE_TIMER_CREATE #undef HAVE_CLOCK_GETTIME +#undef HAVE_XATTR /* Define, if needed, for accessing large files. */ #undef _LARGE_FILES diff --git a/src/configure.ac b/src/configure.ac index bfdcfea4d24a25..e21e23490af128 100644 --- a/src/configure.ac +++ b/src/configure.ac @@ -513,6 +513,18 @@ if test "x$found_smack" = "x"; then fi fi +dnl enable xattr support +AC_MSG_CHECKING(--enable-xattr argument) +AC_ARG_ENABLE(xattr, + [ --disable-xattr Do not check for XATTR support.], + , enable_xattr="yes") +if test "$enable_xattr" = "yes"; then + AC_MSG_RESULT(yes) + AC_CHECK_HEADER([attr/xattr.h], [AC_DEFINE(HAVE_XATTR)]) +else + AC_MSG_RESULT(no) +fi + dnl Check user requested features. AC_MSG_CHECKING(--with-features argument) diff --git a/src/errors.h b/src/errors.h index 6b4416963a9464..16b38cf99aed3c 100644 --- a/src/errors.h +++ b/src/errors.h @@ -3552,6 +3552,14 @@ EXTERN char e_positional_arg_num_type_inconsistent_str_str[] INIT(= N_("E1504: Positional argument %d type used inconsistently: %s/%s")); EXTERN char e_invalid_format_specifier_str[] INIT(= N_("E1505: Invalid format specifier: %s")); -// E1506 - E1519 unused +EXTERN char e_xattr_erange[] + INIT(= N_("E1506: Buffer too small to copy xattr value or key")); +EXTERN char e_xattr_enotsup[] + INIT(= N_("E1507: Extended attributes are not supported by the filesystem")); +EXTERN char e_xattr_e2big[] + INIT(= N_("E1508: size of the extended attribute value is larger than the maximum size allowed")); +EXTERN char e_xattr_other[] + INIT(= N_("E1509: error occured when reading or writing extended attribute")); +// E1509 - E1519 unused EXTERN char e_aptypes_is_null_nr_str[] INIT(= "E1520: Internal error: ap_types or ap_types[idx] is NULL: %d: %s"); diff --git a/src/evalfunc.c b/src/evalfunc.c index 2cd1985a064320..501ee03582fa73 100644 --- a/src/evalfunc.c +++ b/src/evalfunc.c @@ -6462,6 +6462,13 @@ f_has(typval_T *argvars, typval_T *rettv) 1 #else 0 +#endif + }, + {"xattr", +#ifdef FEAT_XATTR + 1 +#else + 0 #endif }, {"xim", diff --git a/src/feature.h b/src/feature.h index ca180dd1f05390..b26dc6ccf187c4 100644 --- a/src/feature.h +++ b/src/feature.h @@ -22,7 +22,7 @@ * - Add a #define below. * - Add a message in the table above ex_version(). * - Add a string to f_has(). - * - Add a feature to ":help feature-list" in doc/eval.txt. + * - Add a feature to ":help feature-list" in doc/builtin.txt. * - Add feature to ":help +feature-list" in doc/various.txt. * - Add comment for the documentation of commands that use the feature. */ @@ -1175,3 +1175,11 @@ || defined(FEAT_TERMINAL) # define USING_LOAD_LIBRARY #endif + +/* + * XATTR support + */ + +#if defined(FEAT_NORMAL) && defined(HAVE_XATTR) +# define FEAT_XATTR +#endif diff --git a/src/os_unix.c b/src/os_unix.c index c5a54e419e7cb9..674dd96666e32c 100644 --- a/src/os_unix.c +++ b/src/os_unix.c @@ -35,6 +35,11 @@ static int selinux_enabled = -1; #endif +#ifdef FEAT_XATTR +# include +# define XATTR_VAL_LEN 1024 +#endif + #ifdef HAVE_SMACK # include # include @@ -3096,6 +3101,96 @@ mch_copy_sec(char_u *from_file, char_u *to_file) } #endif // HAVE_SMACK +#ifdef FEAT_XATTR +/* + * Copy extended attributes from_file to to_file + */ + void +mch_copy_xattr(char_u *from_file, char_u *to_file) +{ + char *xattr_buf; + size_t size; + size_t tsize; + ssize_t keylen, vallen, max_vallen = 0; + char *key; + char *val = NULL; + char *errmsg = NULL; + + if (from_file == NULL) + return; + + // get the length of the extended attributes + size = listxattr((char *)from_file, NULL, 0); + // not supported or no attributes to copy + if (errno == ENOTSUP || size == 0) + return; + xattr_buf = (char*)alloc(size); + if (xattr_buf == NULL) + return; + size = listxattr((char *)from_file, xattr_buf, size); + tsize = size; + + errno = 0; + + for (int round = 0; round < 2; round++) + { + + key = xattr_buf; + if (round == 1) + size = tsize; + + while (size > 0) + { + vallen = getxattr((char *)from_file, key, + val, round ? max_vallen : 0); + // only set the attribute in the second round + if (vallen >= 0 && round && + setxattr((char *)to_file, key, val, vallen, 0) == 0) + ; + else if (errno) + { + switch (errno) + { + case E2BIG: + errmsg = e_xattr_e2big; + goto error_exit; + case ENOTSUP: + errmsg = e_xattr_enotsup; + goto error_exit; + case ERANGE: + errmsg = e_xattr_erange; + goto error_exit; + default: + errmsg = e_xattr_other; + goto error_exit; + } + } + + if (round == 0 && vallen > max_vallen) + max_vallen = vallen; + + // add one for terminating null + keylen = STRLEN(key) + 1; + size -= keylen; + key += keylen; + } + if (round) + break; + + val = (char*)alloc(max_vallen + 1); + if (val == NULL) + goto error_exit; + + } +error_exit: + vim_free(xattr_buf); + vim_free(val); + + if (errmsg != NULL) + emsg((char *)errmsg); +} +#endif + /* * Return a pointer to the ACL of file "fname" in allocated memory. * Return NULL if the ACL is not available for whatever reason. diff --git a/src/proto/os_unix.pro b/src/proto/os_unix.pro index c3a8483f876e83..6e13de6caa79d0 100644 --- a/src/proto/os_unix.pro +++ b/src/proto/os_unix.pro @@ -37,6 +37,7 @@ long mch_getperm(char_u *name); int mch_setperm(char_u *name, long perm); int mch_fsetperm(int fd, long perm); void mch_copy_sec(char_u *from_file, char_u *to_file); +void mch_copy_xattr(char_u *from_file, char_u *to_file); vim_acl_T mch_get_acl(char_u *fname); void mch_set_acl(char_u *fname, vim_acl_T aclent); void mch_free_acl(vim_acl_T aclent); diff --git a/src/testdir/test_writefile.vim b/src/testdir/test_writefile.vim index 140b2ee0375cca..a54efa7cf967f6 100644 --- a/src/testdir/test_writefile.vim +++ b/src/testdir/test_writefile.vim @@ -977,4 +977,27 @@ func Test_wq_quitpre_autocommand() call delete('Xsomefile') endfunc +func Test_write_with_xattr_support() + CheckLinux + CheckExecutable setfattr + + let contents = ["file with xattrs", "line two"] + call writefile(contents, 'Xwattr.txt', 'D') + " write a couple of xattr + call system('setfattr -n user.cookie -v chocolate Xwattr.txt') + call system('setfattr -n user.frieda -v bar Xwattr.txt') + call system('setfattr -n user.empty Xwattr.txt') + + set backupcopy=no writebackup& backup& + sp Xwattr.txt + w + $r! getfattr -d % + let expected = ['file with xattrs', 'line two', '# file: Xwattr.txt', 'user.cookie="chocolate"', 'user.empty=""', 'user.frieda="bar"', ''] + call assert_equal(expected, getline(1,'$')) + + set backupcopy& + bw! + +endfunc + " vim: shiftwidth=2 sts=2 expandtab diff --git a/src/version.c b/src/version.c index e625ea674ba4b1..191d99e19e2309 100644 --- a/src/version.c +++ b/src/version.c @@ -654,6 +654,11 @@ static char *(features[]) = "-X11", # endif #endif +# ifdef FEAT_XATTR + "+xattr", +# else + "-xattr", +# endif #ifdef FEAT_XFONTSET "+xfontset", #else