diff options
Diffstat (limited to 'src/fileio.c')
| -rw-r--r-- | src/fileio.c | 820 |
1 files changed, 510 insertions, 310 deletions
diff --git a/src/fileio.c b/src/fileio.c index a5d29d81fb7..12da7a9ed3a 100644 --- a/src/fileio.c +++ b/src/fileio.c @@ -56,6 +56,10 @@ along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>. */ #include "region-cache.h" #include "frame.h" +#ifdef HAVE_ANDROID +#include "android.h" +#endif /* HAVE_ANDROID */ + #ifdef HAVE_LINUX_FS_H # include <sys/ioctl.h> # include <linux/fs.h> @@ -109,6 +113,42 @@ along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>. */ #include "commands.h" +#if !defined HAVE_ANDROID || defined ANDROID_STUBIFY + +/* Type describing a file descriptor used by functions such as + `insert-file-contents'. */ + +typedef int emacs_fd; + +/* Function used to read and open from such a file descriptor. */ + +#define emacs_fd_open emacs_open +#define emacs_fd_close emacs_close +#define emacs_fd_read emacs_read_quit +#define emacs_fd_lseek lseek +#define emacs_fd_fstat sys_fstat +#define emacs_fd_valid_p(fd) ((fd) >= 0) + +/* This is not used on MS Windows. */ + +#ifndef WINDOWSNT +#define emacs_fd_to_int(fds) (fds) +#endif /* WINDOWSNT */ + +#else /* HAVE_ANDROID && !defined ANDROID_STUBIFY */ + +typedef struct android_fd_or_asset emacs_fd; + +#define emacs_fd_open android_open_asset +#define emacs_fd_close android_close_asset +#define emacs_fd_read android_asset_read_quit +#define emacs_fd_lseek android_asset_lseek +#define emacs_fd_fstat android_asset_fstat +#define emacs_fd_valid_p(fd) ((fd).asset != ((void *) -1)) +#define emacs_fd_to_int(fds) ((fds).asset ? -1 : (fds).fd) + +#endif /* !defined HAVE_ANDROID || defined ANDROID_STUBIFY */ + /* True during writing of auto-save files. */ static bool auto_saving; @@ -134,13 +174,52 @@ static dev_t timestamp_file_system; is added here. */ static Lisp_Object Vwrite_region_annotation_buffers; -static Lisp_Object file_name_directory (Lisp_Object); +static Lisp_Object emacs_readlinkat (int, char const *); static bool a_write (int, Lisp_Object, ptrdiff_t, ptrdiff_t, Lisp_Object *, struct coding_system *); static bool e_write (int, Lisp_Object, ptrdiff_t, ptrdiff_t, struct coding_system *); + +/* Establish that ENCODED is not contained within a special directory + whose contents are not eligible for Unix VFS operations. Signal a + `file-error' with REASON if it does. */ + +static void +check_vfs_filename (Lisp_Object encoded, const char *reason) +{ +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + const char *name; + + name = SSDATA (encoded); + + if (android_is_special_directory (name, "/assets") + || android_is_special_directory (name, "/content")) + xsignal2 (Qfile_error, build_string (reason), encoded); +#endif /* defined HAVE_ANDROID && !defined ANDROID_STUBIFY */ +} + +#ifdef HAVE_LIBSELINUX + +/* Return whether SELinux is enabled and pertinent to FILE. Provide + for cases where FILE is or is a constituent of a special + directory, such as /assets or /content on Android. */ + +static bool +selinux_enabled_p (const char *file) +{ + return (is_selinux_enabled () +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + && !android_is_special_directory (file, "/assets") + && !android_is_special_directory (file, "/content") +#endif /* defined HAVE_ANDROID && !defined ANDROID_STUBIFY */ + ); +} + +#endif /* HAVE_LIBSELINUX */ + + /* Test whether FILE is accessible for AMODE. Return true if successful, false (setting errno) otherwise. */ @@ -159,7 +238,7 @@ file_access_p (char const *file, int amode) } #endif - if (faccessat (AT_FDCWD, file, amode, AT_EACCESS) == 0) + if (sys_faccessat (AT_FDCWD, file, amode, AT_EACCESS) == 0) return true; #ifdef CYGWIN @@ -263,11 +342,20 @@ close_file_unwind (int fd) emacs_close (fd); } +static void +close_file_unwind_emacs_fd (void *ptr) +{ + emacs_fd *fd; + + fd = ptr; + emacs_fd_close (*fd); +} + void fclose_unwind (void *arg) { FILE *stream = arg; - fclose (stream); + emacs_fclose (stream); } /* Restore point, having saved it as a marker. */ @@ -369,7 +457,7 @@ Given a Unix syntax file name, returns a string ending in slash. */) /* Return the directory component of FILENAME, or nil if FILENAME does not contain a directory component. */ -static Lisp_Object +Lisp_Object file_name_directory (Lisp_Object filename) { char *beg = SSDATA (filename); @@ -755,7 +843,7 @@ For that reason, you should normally use `make-temp-file' instead. */) DEFUN ("file-name-concat", Ffile_name_concat, Sfile_name_concat, 1, MANY, 0, doc: /* Append COMPONENTS to DIRECTORY and return the resulting string. -Elements in COMPONENTS must be a string or nil. +Each element in COMPONENTS must be a string or nil. DIRECTORY or the non-final elements in COMPONENTS may or may not end with a slash -- if they don't end with a slash, a slash will be inserted before concatenating. @@ -888,6 +976,10 @@ user_homedir (char const *name) p[length] = 0; struct passwd *pw = getpwnam (p); SAFE_FREE (); +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + if (pw && !pw->pw_dir && pw->pw_uid == getuid ()) + return (char *) android_get_home_directory (); +#endif if (!pw || (pw->pw_dir && !IS_ABSOLUTE_FILE_NAME (pw->pw_dir))) return NULL; return pw->pw_dir; @@ -1878,6 +1970,11 @@ get_homedir (void) pw = getpwuid (getuid ()); if (pw) home = pw->pw_dir; + +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + if (!home && pw && pw->pw_uid == getuid ()) + return android_get_home_directory (); +#endif if (!home) return ""; } @@ -2176,7 +2273,8 @@ permissions. */) #else bool already_exists = false; mode_t new_mask; - int ifd, ofd; + emacs_fd ifd; + int ofd; struct stat st; #endif @@ -2219,26 +2317,31 @@ permissions. */) report_file_error ("Copying permissions to", newname); } #else /* not WINDOWSNT */ - ifd = emacs_open (SSDATA (encoded_file), O_RDONLY, 0); + ifd = emacs_fd_open (SSDATA (encoded_file), O_RDONLY | O_NONBLOCK, 0); - if (ifd < 0) + if (!emacs_fd_valid_p (ifd)) report_file_error ("Opening input file", file); - record_unwind_protect_int (close_file_unwind, ifd); + record_unwind_protect_ptr (close_file_unwind_emacs_fd, &ifd); - if (fstat (ifd, &st) != 0) + if (emacs_fd_fstat (ifd, &st) != 0) report_file_error ("Input file status", file); if (!NILP (preserve_permissions)) { #if HAVE_LIBSELINUX - if (is_selinux_enabled ()) + if (selinux_enabled_p (SSDATA (encoded_file)) + /* Eschew copying SELinux contexts if they're inapplicable + to the destination file. */ + && selinux_enabled_p (SSDATA (encoded_newname)) + && emacs_fd_to_int (ifd) != -1) { - conlength = fgetfilecon (ifd, &con); + conlength = fgetfilecon (emacs_fd_to_int (ifd), + &con); if (conlength == -1) report_file_error ("Doing fgetfilecon", file); } -#endif +#endif /* HAVE_LIBSELINUX */ } /* We can copy only regular files. */ @@ -2272,7 +2375,7 @@ permissions. */) if (already_exists) { struct stat out_st; - if (fstat (ofd, &out_st) != 0) + if (sys_fstat (ofd, &out_st) != 0) report_file_error ("Output file status", newname); if (st.st_dev == out_st.st_dev && st.st_ino == out_st.st_ino) report_file_errno ("Input and output files are the same", @@ -2283,7 +2386,8 @@ permissions. */) maybe_quit (); - if (clone_file (ofd, ifd)) + if (emacs_fd_to_int (ifd) != -1 + && clone_file (ofd, emacs_fd_to_int (ifd))) newsize = st.st_size; else { @@ -2291,30 +2395,38 @@ permissions. */) ssize_t copied; #ifndef MSDOS - for (newsize = 0; newsize < insize; newsize += copied) + newsize = 0; + + if (emacs_fd_to_int (ifd) != -1) { - /* Copy at most COPY_MAX bytes at a time; this is min - (PTRDIFF_MAX, SIZE_MAX) truncated to a value that is - surely aligned well. */ - ssize_t ssize_max = TYPE_MAXIMUM (ssize_t); - ptrdiff_t copy_max = min (ssize_max, SIZE_MAX) >> 30 << 30; - off_t intail = insize - newsize; - ptrdiff_t len = min (intail, copy_max); - copied = copy_file_range (ifd, NULL, ofd, NULL, len, 0); - if (copied <= 0) - break; - maybe_quit (); + for (; newsize < insize; newsize += copied) + { + /* Copy at most COPY_MAX bytes at a time; this is min + (PTRDIFF_MAX, SIZE_MAX) truncated to a value that is + surely aligned well. */ + ssize_t ssize_max = TYPE_MAXIMUM (ssize_t); + ptrdiff_t copy_max = min (ssize_max, SIZE_MAX) >> 30 << 30; + off_t intail = insize - newsize; + ptrdiff_t len = min (intail, copy_max); + copied = copy_file_range (emacs_fd_to_int (ifd), NULL, + ofd, NULL, len, 0); + if (copied <= 0) + break; + maybe_quit (); + } } #endif /* MSDOS */ /* Fall back on read+write if copy_file_range failed, or if the - input is empty and so could be a /proc file. read+write will - either succeed, or report an error more precisely than - copy_file_range would. */ + input is empty and so could be a /proc file, or if ifd is an + invention of android.c. read+write will either succeed, or + report an error more precisely than copy_file_range + would. */ if (newsize != insize || insize == 0) { char buf[MAX_ALLOCA]; - for (; (copied = emacs_read_quit (ifd, buf, sizeof buf)); + + for (; (copied = emacs_fd_read (ifd, buf, sizeof buf)); newsize += copied) { if (copied < 0) @@ -2362,8 +2474,10 @@ permissions. */) } } - switch (!NILP (preserve_permissions) - ? qcopy_acl (SSDATA (encoded_file), ifd, + switch ((!NILP (preserve_permissions) + && emacs_fd_to_int (ifd) != -1) + ? qcopy_acl (SSDATA (encoded_file), + emacs_fd_to_int (ifd), SSDATA (encoded_newname), ofd, preserved_permissions) : (already_exists @@ -2382,11 +2496,18 @@ permissions. */) { /* Set the modified context back to the file. */ bool fail = fsetfilecon (ofd, con) != 0; + freecon (con); + /* See https://debbugs.gnu.org/11245 for ENOTSUP. */ - if (fail && errno != ENOTSUP) + if (fail +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + /* Treat SELinux errors copying files leniently on Android, + since the system usually forbids user programs from + changing file contexts. */ + && errno != EACCES +#endif /* defined HAVE_ANDROID && !defined ANDROID_STUBIFY */ + && errno != ENOTSUP) report_file_error ("Doing fsetfilecon", newname); - - freecon (con); } #endif @@ -2395,7 +2516,17 @@ permissions. */) struct timespec ts[2]; ts[0] = get_stat_atime (&st); ts[1] = get_stat_mtime (&st); - if (futimens (ofd, ts) != 0) + if (futimens (ofd, ts) != 0 + /* Various versions of the Android C library are missing + futimens, prompting Gnulib to install a fallback that + uses fdutimens instead. However, fdutimens is not + supported on many Android kernels, so just silently fail + if errno is ENOTSUP or ENOSYS. */ +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + && errno != ENOTSUP + && errno != ENOSYS +#endif + ) xsignal2 (Qfile_date_error, build_string ("Cannot set file date"), newname); } @@ -2403,7 +2534,9 @@ permissions. */) if (emacs_close (ofd) < 0) report_file_error ("Write error", newname); - emacs_close (ifd); + /* Note that ifd is not closed twice because unwind_protects are + discarded at the end of this function. */ + emacs_fd_close (ifd); #ifdef MSDOS /* In DJGPP v2.0 and later, fstat usually returns true file mode bits, @@ -2436,7 +2569,7 @@ DEFUN ("make-directory-internal", Fmake_directory_internal, dir = SSDATA (encoded_dir); - if (mkdir (dir, 0777 & ~auto_saving_dir_umask) != 0) + if (emacs_mkdir (dir, 0777 & ~auto_saving_dir_umask) != 0) report_file_error ("Creating directory", directory); return Qnil; @@ -2455,47 +2588,26 @@ DEFUN ("delete-directory-internal", Fdelete_directory_internal, encoded_dir = ENCODE_FILE (directory); dir = SSDATA (encoded_dir); - if (rmdir (dir) != 0) + if (emacs_rmdir (dir) != 0) report_file_error ("Removing directory", directory); return Qnil; } -DEFUN ("delete-file", Fdelete_file, Sdelete_file, 1, 2, - "(list (read-file-name \ - (if (and delete-by-moving-to-trash (null current-prefix-arg)) \ - \"Move file to trash: \" \"Delete file: \") \ - nil default-directory (confirm-nonexistent-file-or-buffer)) \ - (null current-prefix-arg))", - doc: /* Delete file named FILENAME. If it is a symlink, remove the symlink. -If file has multiple names, it continues to exist with the other names. -TRASH non-nil means to trash the file instead of deleting, provided -`delete-by-moving-to-trash' is non-nil. - -When called interactively, TRASH is t if no prefix argument is given. -With a prefix argument, TRASH is nil. */) - (Lisp_Object filename, Lisp_Object trash) +DEFUN ("delete-file-internal", Fdelete_file_internal, Sdelete_file_internal, 1, 1, 0, + doc: /* Delete file named FILENAME; internal use only. +If it is a symlink, remove the symlink. +If file has multiple names, it continues to exist with the other names. */) + (Lisp_Object filename) { - Lisp_Object handler; Lisp_Object encoded_file; - if (!NILP (Ffile_directory_p (filename)) - && NILP (Ffile_symlink_p (filename))) - xsignal2 (Qfile_error, - build_string ("Removing old name: is a directory"), - filename); + CHECK_STRING (filename); filename = Fexpand_file_name (filename, Qnil); - - handler = Ffind_file_name_handler (filename, Qdelete_file); - if (!NILP (handler)) - return call3 (handler, Qdelete_file, filename, trash); - - if (delete_by_moving_to_trash && !NILP (trash)) - return call1 (Qmove_file_to_trash, filename); - encoded_file = ENCODE_FILE (filename); - if (unlink (SSDATA (encoded_file)) != 0 && errno != ENOENT) + if (emacs_unlink (SSDATA (encoded_file)) != 0 + && errno != ENOENT) report_file_error ("Removing old name", filename); return Qnil; } @@ -2516,7 +2628,7 @@ internal_delete_file (Lisp_Object filename) { Lisp_Object tem; - tem = internal_condition_case_2 (Fdelete_file, filename, Qnil, + tem = internal_condition_case_1 (Fdelete_file_internal, filename, Qt, internal_delete_file_1); return NILP (tem); } @@ -2524,7 +2636,7 @@ internal_delete_file (Lisp_Object filename) #endif /* Return -1 if FILE is a case-insensitive file name, 0 if not, - and a positive errno value if the result cannot be determined. */ + and 1 if the result cannot be determined. */ static int file_name_case_insensitive_err (Lisp_Object file) @@ -2558,7 +2670,7 @@ file_name_case_insensitive_err (Lisp_Object file) return - (res == 0); # endif if (errno != EINVAL) - return errno; + return 1; #endif #if defined CYGWIN || defined DOS_NT @@ -2658,8 +2770,10 @@ This is what happens in interactive use with M-x. */) int rename_errno UNINIT; if (!plain_rename) { - if (renameat_noreplace (AT_FDCWD, SSDATA (encoded_file), - AT_FDCWD, SSDATA (encoded_newname)) + if (emacs_renameat_noreplace (AT_FDCWD, + SSDATA (encoded_file), + AT_FDCWD, + SSDATA (encoded_newname)) == 0) return Qnil; @@ -2681,7 +2795,8 @@ This is what happens in interactive use with M-x. */) if (plain_rename) { - if (rename (SSDATA (encoded_file), SSDATA (encoded_newname)) == 0) + if (emacs_rename (SSDATA (encoded_file), + SSDATA (encoded_newname)) == 0) return Qnil; rename_errno = errno; /* Don't prompt again. */ @@ -2705,38 +2820,26 @@ This is what happens in interactive use with M-x. */) } if (dirp) call4 (Qcopy_directory, file, newname, Qt, Qnil); - else - { - Lisp_Object symlink_target - = (S_ISLNK (file_st.st_mode) - ? check_emacs_readlinkat (AT_FDCWD, file, SSDATA (encoded_file)) - : Qnil); - if (!NILP (symlink_target)) - Fmake_symbolic_link (symlink_target, newname, ok_if_already_exists); - else if (S_ISFIFO (file_st.st_mode)) - { - /* If it's a FIFO, calling `copy-file' will hang if it's a - inter-file system move, so do it here. (It will signal - an error in that case, but it won't hang in any case.) */ - if (!NILP (ok_if_already_exists)) - barf_or_query_if_file_exists (newname, false, - "rename to it", - FIXNUMP (ok_if_already_exists), - false); - if (rename (SSDATA (encoded_file), SSDATA (encoded_newname)) != 0) - report_file_errno ("Renaming", list2 (file, newname), errno); - return Qnil; - } + else if (S_ISREG (file_st.st_mode)) + Fcopy_file (file, newname, ok_if_already_exists, Qt, Qt, Qt); + else if (S_ISLNK (file_st.st_mode)) + { + Lisp_Object target = emacs_readlinkat (AT_FDCWD, + SSDATA (encoded_file)); + if (!NILP (target)) + Fmake_symbolic_link (target, newname, ok_if_already_exists); else - Fcopy_file (file, newname, ok_if_already_exists, Qt, Qt, Qt); + report_file_error ("Renaming", list2 (file, newname)); } + else + report_file_errno ("Renaming", list2 (file, newname), rename_errno); specpdl_ref count = SPECPDL_INDEX (); specbind (Qdelete_by_moving_to_trash, Qnil); if (dirp) call2 (Qdelete_directory, file, Qt); else - Fdelete_file (file, Qnil); + call2 (Qdelete_file, file, Qnil); return unbind_to (count, Qnil); } @@ -2774,6 +2877,10 @@ This is what happens in interactive use with M-x. */) encoded_file = ENCODE_FILE (file); encoded_newname = ENCODE_FILE (newname); + check_vfs_filename (encoded_file, "Trying to create hard link to " + "file within special directory"); + check_vfs_filename (encoded_newname, "Trying to create hard link" + " within special directory"); if (link (SSDATA (encoded_file), SSDATA (encoded_newname)) == 0) return Qnil; @@ -2784,7 +2891,7 @@ This is what happens in interactive use with M-x. */) || FIXNUMP (ok_if_already_exists)) barf_or_query_if_file_exists (newname, true, "make it a new name", FIXNUMP (ok_if_already_exists), false); - unlink (SSDATA (newname)); + emacs_unlink (SSDATA (newname)); if (link (SSDATA (encoded_file), SSDATA (encoded_newname)) == 0) return Qnil; } @@ -2828,7 +2935,8 @@ This happens for interactive use with M-x. */) encoded_target = ENCODE_FILE (target); encoded_linkname = ENCODE_FILE (linkname); - if (symlink (SSDATA (encoded_target), SSDATA (encoded_linkname)) == 0) + if (emacs_symlink (SSDATA (encoded_target), + SSDATA (encoded_linkname)) == 0) return Qnil; if (errno == ENOSYS) @@ -2841,8 +2949,9 @@ This happens for interactive use with M-x. */) || FIXNUMP (ok_if_already_exists)) barf_or_query_if_file_exists (linkname, true, "make it a link", FIXNUMP (ok_if_already_exists), false); - unlink (SSDATA (encoded_linkname)); - if (symlink (SSDATA (encoded_target), SSDATA (encoded_linkname)) == 0) + emacs_unlink (SSDATA (encoded_linkname)); + if (emacs_symlink (SSDATA (encoded_target), + SSDATA (encoded_linkname)) == 0) return Qnil; } @@ -2982,7 +3091,8 @@ If there is no error, returns nil. */) encoded_filename = ENCODE_FILE (absname); - if (faccessat (AT_FDCWD, SSDATA (encoded_filename), R_OK, AT_EACCESS) != 0) + if (sys_faccessat (AT_FDCWD, SSDATA (encoded_filename), R_OK, + AT_EACCESS) != 0) report_file_error (SSDATA (string), filename); return Qnil; @@ -2990,15 +3100,29 @@ If there is no error, returns nil. */) /* Relative to directory FD, return the symbolic link value of FILENAME. On failure, return nil (setting errno). */ + static Lisp_Object emacs_readlinkat (int fd, char const *filename) { - static struct allocator const emacs_norealloc_allocator = - { xmalloc, NULL, xfree, memory_full }; + static struct allocator const emacs_norealloc_allocator = { + xmalloc, + NULL, + xfree, + memory_full, + }; + Lisp_Object val; char readlink_buf[1024]; - char *buf = careadlinkat (fd, filename, readlink_buf, sizeof readlink_buf, - &emacs_norealloc_allocator, readlinkat); + char *buf; + + buf = careadlinkat (fd, filename, readlink_buf, sizeof readlink_buf, + &emacs_norealloc_allocator, +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + android_readlinkat +#else /* !HAVE_ANDROID || ANDROID_STUBIFY */ + readlinkat +#endif /* HAVE_ANDROID && !ANDROID_STUBIFY */ + ); if (!buf) return Qnil; @@ -3084,12 +3208,13 @@ file_directory_p (Lisp_Object file) { #ifdef DOS_NT /* This is cheaper than 'stat'. */ - bool retval = faccessat (AT_FDCWD, SSDATA (file), D_OK, AT_EACCESS) == 0; + bool retval = sys_faccessat (AT_FDCWD, SSDATA (file), + D_OK, AT_EACCESS) == 0; if (!retval && errno == EACCES) errno = ENOTDIR; /* like the non-DOS_NT branch below does */ return retval; #else -# ifdef O_PATH +# if defined O_PATH && !(defined HAVE_ANDROID && !defined ANDROID_STUBIFY) /* Use O_PATH if available, as it avoids races and EOVERFLOW issues. */ int fd = emacs_openat (AT_FDCWD, SSDATA (file), O_PATH | O_CLOEXEC | O_DIRECTORY, 0); @@ -3198,7 +3323,11 @@ file_accessible_directory_p (Lisp_Object file) There are three exceptions: "", "/", and "//". Leave "" alone, as it's invalid. Append only "." to the other two exceptions as "/" and "//" are distinct on some platforms, whereas "/", "///", - "////", etc. are all equivalent. */ + "////", etc. are all equivalent. + + Android has a special directory named "/assets". There is no "." + directory there, but appending a "/" is sufficient to check + whether or not it is a directory. */ if (! len) dir = data; else @@ -3208,6 +3337,7 @@ file_accessible_directory_p (Lisp_Object file) special cases "/" and "//", and it's a safe optimization here. After appending '.', append another '/' to work around a macOS bug (Bug#30350). */ + static char const appended[] = "/./"; char *buf = SAFE_ALLOCA (len + sizeof appended); memcpy (buf, data, len); @@ -3267,6 +3397,9 @@ or if SELinux is disabled, or if Emacs lacks SELinux support. */) { Lisp_Object user = Qnil, role = Qnil, type = Qnil, range = Qnil; Lisp_Object absname = expand_and_dir_to_file (filename); +#ifdef HAVE_LIBSELINUX + const char *file; +#endif /* HAVE_LIBSELINUX */ /* If the file name has special constructs in it, call the corresponding file name handler. */ @@ -3275,11 +3408,13 @@ or if SELinux is disabled, or if Emacs lacks SELinux support. */) if (!NILP (handler)) return call2 (handler, Qfile_selinux_context, absname); -#if HAVE_LIBSELINUX - if (is_selinux_enabled ()) +#ifdef HAVE_LIBSELINUX + file = SSDATA (ENCODE_FILE (absname)); + + if (selinux_enabled_p (file)) { char *con; - int conlength = lgetfilecon (SSDATA (ENCODE_FILE (absname)), &con); + int conlength = lgetfilecon (file, &con); if (conlength > 0) { context_t context = context_new (con); @@ -3298,7 +3433,7 @@ or if SELinux is disabled, or if Emacs lacks SELinux support. */) || errno == ENOTSUP)) report_file_error ("getting SELinux context", absname); } -#endif +#endif /* HAVE_LIBSELINUX */ return list4 (user, role, type, range); } @@ -3324,10 +3459,11 @@ or if Emacs was not compiled with SELinux support. */) Lisp_Object type = CAR_SAFE (CDR_SAFE (CDR_SAFE (context))); Lisp_Object range = CAR_SAFE (CDR_SAFE (CDR_SAFE (CDR_SAFE (context)))); char *con; + const char *name; bool fail; int conlength; context_t parsed_con; -#endif +#endif /* HAVE_LIBSELINUX */ absname = Fexpand_file_name (filename, BVAR (current_buffer, directory)); @@ -3338,11 +3474,13 @@ or if Emacs was not compiled with SELinux support. */) return call3 (handler, Qset_file_selinux_context, absname, context); #if HAVE_LIBSELINUX - if (is_selinux_enabled ()) + encoded_absname = ENCODE_FILE (absname); + name = SSDATA (encoded_absname); + + if (selinux_enabled_p (name)) { /* Get current file context. */ - encoded_absname = ENCODE_FILE (absname); - conlength = lgetfilecon (SSDATA (encoded_absname), &con); + conlength = lgetfilecon (name, &con); if (conlength > 0) { parsed_con = context_new (con); @@ -3372,18 +3510,18 @@ or if Emacs was not compiled with SELinux support. */) fail = (lsetfilecon (SSDATA (encoded_absname), context_str (parsed_con)) != 0); + context_free (parsed_con); + freecon (con); + /* See https://debbugs.gnu.org/11245 for ENOTSUP. */ if (fail && errno != ENOTSUP) report_file_error ("Doing lsetfilecon", absname); - - context_free (parsed_con); - freecon (con); return fail ? Qnil : Qt; } else report_file_error ("Doing lgetfilecon", absname); } -#endif +#endif /* HAVE_LIBSELINUX */ return Qnil; } @@ -3479,10 +3617,10 @@ support. */) fail = (acl_set_file (SSDATA (encoded_absname), ACL_TYPE_ACCESS, acl) != 0); + acl_free (acl); if (fail && acl_errno_valid (errno)) report_file_error ("Setting ACL", absname); - acl_free (acl); return fail ? Qnil : Qt; } # endif @@ -3532,6 +3670,8 @@ Interactively, prompt for FILENAME, and read MODE with command from GNU Coreutils. */) (Lisp_Object filename, Lisp_Object mode, Lisp_Object flag) { + Lisp_Object encoded; + CHECK_FIXNUM (mode); int nofollow = symlink_nofollow_flag (flag); Lisp_Object absname = Fexpand_file_name (filename, @@ -3543,9 +3683,10 @@ command from GNU Coreutils. */) if (!NILP (handler)) return call4 (handler, Qset_file_modes, absname, mode, flag); - char *fname = SSDATA (ENCODE_FILE (absname)); + encoded = ENCODE_FILE (absname); + char *fname = SSDATA (encoded); mode_t imode = XFIXNUM (mode) & 07777; - if (fchmodat (AT_FDCWD, fname, imode, nofollow) != 0) + if (emacs_fchmodat (AT_FDCWD, fname, imode, nofollow) != 0) report_file_error ("Doing chmod", absname); return Qnil; @@ -3562,7 +3703,9 @@ in the permissions of newly created files will be disabled. Note that when `write-region' creates a file, it resets the execute bit, even if the mask set by this function allows that bit -by having the corresponding bit in the mask reset. */) +by having the corresponding bit in the mask reset. + +See also `with-file-modes'. */) (Lisp_Object mode) { mode_t oldrealmask, oldumask, newumask; @@ -3615,6 +3758,8 @@ TIMESTAMP is in the format of `current-time'. */) return call4 (handler, Qset_file_times, absname, timestamp, flag); Lisp_Object encoded_absname = ENCODE_FILE (absname); + check_vfs_filename (encoded_absname, "Trying to set access times of" + " file within special directory"); if (utimensat (AT_FDCWD, SSDATA (encoded_absname), ts, nofollow) != 0) { @@ -3647,6 +3792,7 @@ otherwise, if FILE2 does not exist, the answer is t. */) (Lisp_Object file1, Lisp_Object file2) { struct stat st1, st2; + Lisp_Object encoded; CHECK_STRING (file1); CHECK_STRING (file2); @@ -3663,8 +3809,10 @@ otherwise, if FILE2 does not exist, the answer is t. */) if (!NILP (handler)) return call3 (handler, Qfile_newer_than_file_p, absname1, absname2); + encoded = ENCODE_FILE (absname1); + int err1; - if (emacs_fstatat (AT_FDCWD, SSDATA (ENCODE_FILE (absname1)), &st1, 0) == 0) + if (emacs_fstatat (AT_FDCWD, SSDATA (encoded), &st1, 0) == 0) err1 = 0; else { @@ -3753,7 +3901,7 @@ union read_non_regular { struct { - int fd; + emacs_fd fd; ptrdiff_t inserted, trytry; } s; GCALIGNED_UNION_MEMBER @@ -3764,11 +3912,12 @@ static Lisp_Object read_non_regular (Lisp_Object state) { union read_non_regular *data = XFIXNUMPTR (state); - int nbytes = emacs_read_quit (data->s.fd, - ((char *) BEG_ADDR + PT_BYTE - BEG_BYTE - + data->s.inserted), - data->s.trytry); - return make_fixnum (nbytes); + intmax_t nbytes + = emacs_fd_read (data->s.fd, + ((char *) BEG_ADDR + PT_BYTE - BEG_BYTE + + data->s.inserted), + data->s.trytry); + return make_int (nbytes); } @@ -3896,15 +4045,22 @@ characters in the buffer. If VISIT is non-nil, BEG and END must be nil. When inserting data from a special file (e.g., /dev/urandom), you can't specify VISIT or BEG, and END should be specified to avoid -inserting unlimited data into the buffer. - -If optional fifth argument REPLACE is non-nil, replace the current -buffer contents (in the accessible portion) with the file contents. -This is better than simply deleting and inserting the whole thing -because (1) it preserves some marker positions (in unchanged portions -at the start and end of the buffer) and (2) it puts less data in the -undo list. When REPLACE is non-nil, the second return value is the -number of characters that replace previous buffer contents. +inserting unlimited data into the buffer from some special files +which otherwise could supply infinite amounts of data. + +If optional fifth argument REPLACE is non-nil and FILENAME names a +regular file, replace the current buffer contents (in the accessible +portion) with the file's contents. This is better than simply +deleting and inserting the whole thing because (1) it preserves some +marker positions (in unchanged portions at the start and end of the +buffer) and (2) it puts less data in the undo list. When REPLACE is +non-nil, the second element of the return value is the number of +characters that replace the previous buffer contents. + +If FILENAME is not a regular file and REPLACE is `if-regular', erase +the accessible portion of the buffer and insert the new contents. Any +other non-nil value of REPLACE will signal an error if FILENAME is not +a regular file. This function does code conversion according to the value of `coding-system-for-read' or `file-coding-system-alist', and sets the @@ -3912,14 +4068,13 @@ variable `last-coding-system-used' to the coding system actually used. In addition, this function decodes the inserted text from known formats by calling `format-decode', which see. */) - (Lisp_Object filename, Lisp_Object visit, Lisp_Object beg, Lisp_Object end, Lisp_Object replace) + (Lisp_Object filename, Lisp_Object visit, Lisp_Object beg, Lisp_Object end, + Lisp_Object replace) { struct stat st; struct timespec mtime; - int fd; + emacs_fd fd; ptrdiff_t inserted = 0; - ptrdiff_t how_much; - off_t beg_offset, end_offset; int unprocessed; specpdl_ref count = SPECPDL_INDEX (); Lisp_Object handler, val, insval, orig_filename, old_undo; @@ -3932,7 +4087,8 @@ by calling `format-decode', which see. */) bool replace_handled = false; bool set_coding_system = false; Lisp_Object coding_system; - bool read_quit = false; + /* Negative if read error, 0 if OK so far, positive if quit. */ + ptrdiff_t read_quit = 0; /* If the undo log only contains the insertion, there's no point keeping it. It's typically when we first fill a file-buffer. */ bool empty_undo_list_p @@ -3981,11 +4137,22 @@ by calling `format-decode', which see. */) goto handled; } + if (!NILP (visit)) + { + if (!NILP (beg) || !NILP (end)) + error ("Attempt to visit less than an entire file"); + if (BEG < Z && NILP (replace)) + error ("Cannot do file visiting in a non-empty buffer"); + } + + off_t beg_offset = !NILP (beg) ? file_offset (beg) : 0; + off_t end_offset = !NILP (end) ? file_offset (end) : -1; + orig_filename = filename; filename = ENCODE_FILE (filename); - fd = emacs_open (SSDATA (filename), O_RDONLY, 0); - if (fd < 0) + fd = emacs_fd_open (SSDATA (filename), O_RDONLY, 0); + if (!emacs_fd_valid_p (fd)) { save_errno = errno; if (NILP (visit)) @@ -4003,7 +4170,7 @@ by calling `format-decode', which see. */) } specpdl_ref fd_index = SPECPDL_INDEX (); - record_unwind_protect_int (close_file_unwind, fd); + record_unwind_protect_ptr (close_file_unwind_emacs_fd, &fd); /* Replacement should preserve point as it preserves markers. */ if (!NILP (replace)) @@ -4013,50 +4180,45 @@ by calling `format-decode', which see. */) XCAR (XCAR (window_markers))); } - if (fstat (fd, &st) != 0) + if (emacs_fd_fstat (fd, &st) != 0) report_file_error ("Input file status", orig_filename); mtime = get_stat_mtime (&st); - /* This code will need to be changed in order to work on named - pipes, and it's probably just not worth it. So we should at - least signal an error. */ + /* The REPLACE code will need to be changed in order to work on + named pipes, and it's probably just not worth it. So we should + at least signal an error. */ + if (!S_ISREG (st.st_mode)) { regular = false; - seekable = lseek (fd, 0, SEEK_CUR) != (off_t) -1; - if (! NILP (visit)) - { - eassert (inserted == 0); - goto notfound; - } + if (!NILP (replace)) + { + if (!EQ (replace, Qif_regular)) + xsignal2 (Qfile_error, + build_string ("not a regular file"), orig_filename); + else + /* Set REPLACE to Qunbound, indicating that we are trying + to replace the buffer contents with that of a + non-regular file. */ + replace = Qunbound; + } - if (!NILP (beg) && !seekable) + /* Forbid specifying BEG together with a special file, as per + the doc string. */ + + if (!NILP (beg)) xsignal2 (Qfile_error, build_string ("cannot use a start position in a non-seekable file/device"), orig_filename); - if (!NILP (replace)) - xsignal2 (Qfile_error, - build_string ("not a regular file"), orig_filename); + /* Now ascertain if this file is seekable, by detecting if + seeking leads to -1 being returned. */ + seekable + = emacs_fd_lseek (fd, 0, SEEK_CUR) != (off_t) -1; } - if (!NILP (visit)) - { - if (!NILP (beg) || !NILP (end)) - error ("Attempt to visit less than an entire file"); - if (BEG < Z && NILP (replace)) - error ("Cannot do file visiting in a non-empty buffer"); - } - - if (!NILP (beg)) - beg_offset = file_offset (beg); - else - beg_offset = 0; - - if (!NILP (end)) - end_offset = file_offset (end); - else + if (end_offset < 0) { if (!regular) end_offset = TYPE_MAXIMUM (off_t); @@ -4117,7 +4279,7 @@ by calling `format-decode', which see. */) else { /* Don't try looking inside a file for a coding system - specification if it is not seekable. */ + specification if it is not a regular file. */ if (regular && !NILP (Vset_auto_coding_function)) { /* Find a coding system specified in the heading two @@ -4128,17 +4290,17 @@ by calling `format-decode', which see. */) int nread; if (st.st_size <= (1024 * 4)) - nread = emacs_read_quit (fd, read_buf, 1024 * 4); + nread = emacs_fd_read (fd, read_buf, 1024 * 4); else { - nread = emacs_read_quit (fd, read_buf, 1024); + nread = emacs_fd_read (fd, read_buf, 1024); if (nread == 1024) { int ntail; - if (lseek (fd, - (1024 * 3), SEEK_END) < 0) + if (emacs_fd_lseek (fd, st.st_size - 1024 * 3, SEEK_CUR) < 0) report_file_error ("Setting file position", orig_filename); - ntail = emacs_read_quit (fd, read_buf + nread, 1024 * 3); + ntail = emacs_fd_read (fd, read_buf + nread, 1024 * 3); nread = ntail < 0 ? ntail : nread + ntail; } } @@ -4179,7 +4341,7 @@ by calling `format-decode', which see. */) specpdl_ptr--; /* Rewind the file for the actual read done later. */ - if (lseek (fd, 0, SEEK_SET) < 0) + if (emacs_fd_lseek (fd, 0, SEEK_SET) < 0) report_file_error ("Setting file position", orig_filename); } } @@ -4225,7 +4387,8 @@ by calling `format-decode', which see. */) method and hope for the best. But if we discover the need for conversion, we give up on this method and let the following if-statement handle the replace job. */ - if (!NILP (replace) + if ((!NILP (replace) + && !BASE_EQ (replace, Qunbound)) && BEGV < ZV && (NILP (coding_system) || ! CODING_REQUIRE_DECODING (&coding))) @@ -4238,7 +4401,7 @@ by calling `format-decode', which see. */) if (beg_offset != 0) { - if (lseek (fd, beg_offset, SEEK_SET) < 0) + if (emacs_fd_lseek (fd, beg_offset, SEEK_SET) < 0) report_file_error ("Setting file position", orig_filename); } @@ -4246,7 +4409,7 @@ by calling `format-decode', which see. */) match the text at the beginning of the buffer. */ while (true) { - int nread = emacs_read_quit (fd, read_buf, sizeof read_buf); + int nread = emacs_fd_read (fd, read_buf, sizeof read_buf); if (nread < 0) report_file_error ("Read error", orig_filename); else if (nread == 0) @@ -4281,7 +4444,7 @@ by calling `format-decode', which see. */) there's no need to replace anything. */ if (same_at_start - BEGV_BYTE == end_offset - beg_offset) { - emacs_close (fd); + emacs_fd_close (fd); clear_unwind_protect (fd_index); /* Truncate the buffer to the size of the file. */ @@ -4304,14 +4467,14 @@ by calling `format-decode', which see. */) break; /* How much can we scan in the next step? */ trial = min (curpos, sizeof read_buf); - if (lseek (fd, curpos - trial, SEEK_SET) < 0) + if (emacs_fd_lseek (fd, curpos - trial, SEEK_SET) < 0) report_file_error ("Setting file position", orig_filename); total_read = nread = 0; while (total_read < trial) { - nread = emacs_read_quit (fd, read_buf + total_read, - trial - total_read); + nread = emacs_fd_read (fd, read_buf + total_read, + trial - total_read); if (nread < 0) report_file_error ("Read error", orig_filename); else if (nread == 0) @@ -4412,7 +4575,9 @@ by calling `format-decode', which see. */) is needed, in a simple way that needs a lot of memory. The preceding if-statement handles the case of no conversion in a more optimized way. */ - if (!NILP (replace) && ! replace_handled && BEGV < ZV) + if ((!NILP (replace) + && !BASE_EQ (replace, Qunbound)) + && ! replace_handled && BEGV < ZV) { ptrdiff_t same_at_start_charpos; ptrdiff_t inserted_chars; @@ -4420,7 +4585,7 @@ by calling `format-decode', which see. */) ptrdiff_t bufpos; unsigned char *decoded; ptrdiff_t temp; - ptrdiff_t this = 0; + ptrdiff_t this; specpdl_ref this_count = SPECPDL_INDEX (); bool multibyte = ! NILP (BVAR (current_buffer, enable_multibyte_characters)); @@ -4431,7 +4596,7 @@ by calling `format-decode', which see. */) /* First read the whole file, performing code conversion into CONVERSION_BUFFER. */ - if (lseek (fd, beg_offset, SEEK_SET) < 0) + if (emacs_fd_lseek (fd, beg_offset, SEEK_SET) < 0) report_file_error ("Setting file position", orig_filename); inserted = 0; /* Bytes put into CONVERSION_BUFFER so far. */ @@ -4442,8 +4607,8 @@ by calling `format-decode', which see. */) /* Read at most READ_BUF_SIZE bytes at a time, to allow quitting while reading a huge file. */ - this = emacs_read_quit (fd, read_buf + unprocessed, - READ_BUF_SIZE - unprocessed); + this = emacs_fd_read (fd, read_buf + unprocessed, + READ_BUF_SIZE - unprocessed); if (this <= 0) break; @@ -4458,7 +4623,7 @@ by calling `format-decode', which see. */) if (this < 0) report_file_error ("Read error", orig_filename); - emacs_close (fd); + emacs_fd_close (fd); clear_unwind_protect (fd_index); if (unprocessed > 0) @@ -4597,22 +4762,28 @@ by calling `format-decode', which see. */) prepare_to_modify_buffer (PT, PT, NULL); } + /* If REPLACE is Qunbound, buffer contents are being replaced with + text read from a FIFO or a device. Erase the entire accessible + portion of the buffer. */ + + if (BASE_EQ (replace, Qunbound)) + del_range (BEGV, ZV); + move_gap_both (PT, PT_BYTE); - if (GAP_SIZE < total) - make_gap (total - GAP_SIZE); - if (beg_offset != 0 || !NILP (replace)) + /* Ensure the gap is at least one byte larger than needed for the + estimated file size, so that in the usual case we read to EOF + without reallocating. */ + if (GAP_SIZE <= total) + make_gap (total - GAP_SIZE + 1); + + if (beg_offset != 0 || (!NILP (replace) + && !BASE_EQ (replace, Qunbound))) { - if (lseek (fd, beg_offset, SEEK_SET) < 0) + if (emacs_fd_lseek (fd, beg_offset, SEEK_SET) < 0) report_file_error ("Setting file position", orig_filename); } - /* In the following loop, HOW_MUCH contains the total bytes read so - far for a regular file, and not changed for a special file. But, - before exiting the loop, it is set to a negative value if I/O - error occurs. */ - how_much = 0; - /* Total bytes inserted. */ inserted = 0; @@ -4621,22 +4792,26 @@ by calling `format-decode', which see. */) { ptrdiff_t gap_size = GAP_SIZE; - while (how_much < total) + while (NILP (end) || inserted < total) { - /* `try' is reserved in some compilers (Microsoft C). */ - ptrdiff_t trytry = min (total - how_much, READ_BUF_SIZE); ptrdiff_t this; + if (gap_size == 0) + { + /* The size estimate was wrong. Make the gap 50% larger. */ + make_gap (GAP_SIZE >> 1); + gap_size = GAP_SIZE - inserted; + } + + /* 'try' is reserved in some compilers (Microsoft C). */ + ptrdiff_t trytry = min (gap_size, READ_BUF_SIZE); + if (seekable || !NILP (end)) + trytry = min (trytry, total - inserted); + if (!seekable && NILP (end)) { Lisp_Object nbytes; - - /* Maybe make more room. */ - if (gap_size < trytry) - { - make_gap (trytry - gap_size); - gap_size = GAP_SIZE - inserted; - } + intmax_t number; /* Read from the file, capturing `quit'. When an error occurs, end the loop, and arrange for a quit @@ -4648,38 +4823,32 @@ by calling `format-decode', which see. */) if (NILP (nbytes)) { - read_quit = true; + read_quit = 1; break; } - this = XFIXNUM (nbytes); + if (!integer_to_intmax (nbytes, &number) + && number > PTRDIFF_MAX) + buffer_overflow (); + + this = number; } else - { - /* Allow quitting out of the actual I/O. We don't make text - part of the buffer until all the reading is done, so a C-g - here doesn't do any harm. */ - this = emacs_read_quit (fd, - ((char *) BEG_ADDR + PT_BYTE - BEG_BYTE - + inserted), - trytry); - } + /* Allow quitting out of the actual I/O. We don't make text + part of the buffer until all the reading is done, so a + C-g here doesn't do any harm. */ + this = emacs_fd_read (fd, + ((char *) BEG_ADDR + PT_BYTE - BEG_BYTE + + inserted), + trytry); if (this <= 0) { - how_much = this; + read_quit = this; break; } gap_size -= this; - - /* For a regular file, where TOTAL is the real size, - count HOW_MUCH to compare with it. - For a special file, where TOTAL is just a buffer size, - so don't bother counting in HOW_MUCH. - (INSERTED is where we count the number of characters inserted.) */ - if (seekable || !NILP (end)) - how_much += this; inserted += this; } } @@ -4697,10 +4866,10 @@ by calling `format-decode', which see. */) else Fset (Qdeactivate_mark, Qt); - emacs_close (fd); + emacs_fd_close (fd); clear_unwind_protect (fd_index); - if (how_much < 0) + if (read_quit < 0) report_file_error ("Read error", orig_filename); notfound: @@ -4856,9 +5025,14 @@ by calling `format-decode', which see. */) Funlock_file (BVAR (current_buffer, file_truename)); Funlock_file (filename); } + +#if !defined HAVE_ANDROID || defined ANDROID_STUBIFY + /* Under Android, modtime and st.st_size can be valid even if FD + is not a regular file. */ if (!regular) xsignal2 (Qfile_error, build_string ("not a regular file"), orig_filename); +#endif /* !defined HAVE_ANDROID || defined ANDROID_STUBIFY */ } if (set_coding_system) @@ -4876,8 +5050,10 @@ by calling `format-decode', which see. */) } } - /* Decode file format. */ - if (inserted > 0) + /* Decode file format. Don't do this if Qformat_decode is not + bound, which can happen when called early during loadup. */ + + if (inserted > 0 && !NILP (Ffboundp (Qformat_decode))) { /* Don't run point motion or modification hooks when decoding. */ specpdl_ref count1 = SPECPDL_INDEX (); @@ -5322,6 +5498,7 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename, } encoded_filename = ENCODE_FILE (filename); + fn = SSDATA (encoded_filename); open_flags = O_WRONLY | O_CREAT; open_flags |= EQ (mustbenew, Qexcl) ? O_EXCL : !NILP (append) ? 0 : O_TRUNC; @@ -5408,7 +5585,7 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename, modtime = invalid_timespec (); if (visiting) { - if (fstat (desc, &st) == 0) + if (sys_fstat (desc, &st) == 0) modtime = get_stat_mtime (&st); else ok = 0, save_errno = errno; @@ -5442,42 +5619,52 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename, if (timespec_valid_p (modtime) && ! (valid_timestamp_file_system && st.st_dev == timestamp_file_system)) { - int desc1 = emacs_open (fn, O_WRONLY, 0); - if (desc1 >= 0) + struct stat st1; + + /* The code below previously tried to open FN O_WRONLY, + subsequently calling fstat on the opened file descriptor. + This proved inefficient and resulted in FN being truncated + under several Android filesystems, and as such has been + changed to a call to `stat'. */ + + if (emacs_fstatat (AT_FDCWD, fn, &st1, 0) == 0 + && st.st_dev == st1.st_dev + && (st.st_ino == st1.st_ino +#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY + /* `st1.st_ino' == 0 indicates that the inode number + cannot be extracted from this document file, despite + `st' potentially being backed by a real file. */ + || st1.st_ino == 0 +#endif /* defined HAVE_ANDROID && !defined ANDROID_STUBIFY */ + )) { - struct stat st1; - if (fstat (desc1, &st1) == 0 - && st.st_dev == st1.st_dev && st.st_ino == st1.st_ino) + /* Use the heuristic if it appears to be valid. With neither + O_EXCL nor O_TRUNC, if Emacs happened to write nothing to the + file, the time stamp won't change. Also, some non-POSIX + systems don't update an empty file's time stamp when + truncating it. Finally, file systems with 100 ns or worse + resolution sometimes seem to have bugs: on a system with ns + resolution, checking ns % 100 incorrectly avoids the heuristic + 1% of the time, but the problem should be temporary as we will + try again on the next time stamp. */ + bool use_heuristic + = ((open_flags & (O_EXCL | O_TRUNC)) != 0 + && st.st_size != 0 + && modtime.tv_nsec % 100 != 0); + + struct timespec modtime1 = get_stat_mtime (&st1); + if (use_heuristic + && timespec_cmp (modtime, modtime1) == 0 + && st.st_size == st1.st_size) { - /* Use the heuristic if it appears to be valid. With neither - O_EXCL nor O_TRUNC, if Emacs happened to write nothing to the - file, the time stamp won't change. Also, some non-POSIX - systems don't update an empty file's time stamp when - truncating it. Finally, file systems with 100 ns or worse - resolution sometimes seem to have bugs: on a system with ns - resolution, checking ns % 100 incorrectly avoids the heuristic - 1% of the time, but the problem should be temporary as we will - try again on the next time stamp. */ - bool use_heuristic - = ((open_flags & (O_EXCL | O_TRUNC)) != 0 - && st.st_size != 0 - && modtime.tv_nsec % 100 != 0); - - struct timespec modtime1 = get_stat_mtime (&st1); - if (use_heuristic - && timespec_cmp (modtime, modtime1) == 0 - && st.st_size == st1.st_size) - { - timestamp_file_system = st.st_dev; - valid_timestamp_file_system = 1; - } - else - { - st.st_size = st1.st_size; - modtime = modtime1; - } + timestamp_file_system = st.st_dev; + valid_timestamp_file_system = 1; + } + else + { + st.st_size = st1.st_size; + modtime = modtime1; } - emacs_close (desc1); } } @@ -5823,7 +6010,6 @@ See Info node `(elisp)Modification Time' for more details. */) return call2 (handler, Qverify_visited_file_modtime, buf); filename = ENCODE_FILE (BVAR (b, filename)); - mtime = (emacs_fstatat (AT_FDCWD, SSDATA (filename), &st, 0) == 0 ? get_stat_mtime (&st) : time_error_value (errno)); @@ -5883,7 +6069,7 @@ in `current-time' or an integer flag as returned by `visited-file-modtime'. */) error ("An indirect buffer does not have a visited file"); else { - register Lisp_Object filename; + register Lisp_Object filename, encoded; struct stat st; Lisp_Object handler; @@ -5896,7 +6082,9 @@ in `current-time' or an integer flag as returned by `visited-file-modtime'. */) /* The handler can find the file name the same way we did. */ return call2 (handler, Qset_visited_file_modtime, Qnil); - if (emacs_fstatat (AT_FDCWD, SSDATA (ENCODE_FILE (filename)), &st, 0) + encoded = ENCODE_FILE (filename); + + if (emacs_fstatat (AT_FDCWD, SSDATA (encoded), &st, 0) == 0) { current_buffer->modtime = get_stat_mtime (&st); @@ -5969,7 +6157,7 @@ do_auto_save_unwind (void *arg) if (stream != NULL) { block_input (); - fclose (stream); + emacs_fclose (stream); unblock_input (); } } @@ -6295,13 +6483,18 @@ effect except for flushing STREAM's data. */) #ifndef DOS_NT +#if defined STAT_STATFS2_BSIZE || defined STAT_STATFS2_FRSIZE \ + || defined STAT_STATFS2_FSIZE || defined STAT_STATFS3_OSF1 \ + || defined STAT_STATFS4 || defined STAT_STATVFS \ + || defined STAT_STATVFS64 + /* Yield a Lisp number equal to BLOCKSIZE * BLOCKS, with the result negated if NEGATE. */ static Lisp_Object blocks_to_bytes (uintmax_t blocksize, uintmax_t blocks, bool negate) { intmax_t n; - if (!INT_MULTIPLY_WRAPV (blocksize, blocks, &n)) + if (!ckd_mul (&n, blocksize, blocks)) return make_int (negate ? -n : n); Lisp_Object bs = make_uint (blocksize); if (negate) @@ -6309,6 +6502,8 @@ blocks_to_bytes (uintmax_t blocksize, uintmax_t blocks, bool negate) return CALLN (Ftimes, bs, make_uint (blocks)); } +#endif + DEFUN ("file-system-info", Ffile_system_info, Sfile_system_info, 1, 1, 0, doc: /* Return storage information about the file system FILENAME is on. Value is a list of numbers (TOTAL FREE AVAIL), where TOTAL is the total @@ -6330,6 +6525,11 @@ If the underlying system call fails, value is nil. */) error ("Invalid handler in `file-name-handler-alist'"); } + /* Try to detect whether or not fsusage.o is actually built. */ +#if defined STAT_STATFS2_BSIZE || defined STAT_STATFS2_FRSIZE \ + || defined STAT_STATFS2_FSIZE || defined STAT_STATFS3_OSF1 \ + || defined STAT_STATFS4 || defined STAT_STATVFS \ + || defined STAT_STATVFS64 struct fs_usage u; if (get_fs_usage (SSDATA (ENCODE_FILE (filename)), NULL, &u) != 0) return errno == ENOSYS ? Qnil : file_attribute_errno (filename, errno); @@ -6337,6 +6537,9 @@ If the underlying system call fails, value is nil. */) blocks_to_bytes (u.fsu_blocksize, u.fsu_bfree, false), blocks_to_bytes (u.fsu_blocksize, u.fsu_bavail, u.fsu_bavail_top_bit_set)); +#else + return Qnil; +#endif } #endif /* !DOS_NT */ @@ -6348,24 +6551,6 @@ init_fileio (void) umask (realmask); valid_timestamp_file_system = 0; - - /* fsync can be a significant performance hit. Often it doesn't - suffice to make the file-save operation survive a crash. For - batch scripts, which are typically part of larger shell commands - that don't fsync other files, its effect on performance can be - significant so its utility is particularly questionable. - Hence, for now by default fsync is used only when interactive. - - For more on why fsync often fails to work on today's hardware, see: - Zheng M et al. Understanding the robustness of SSDs under power fault. - 11th USENIX Conf. on File and Storage Technologies, 2013 (FAST '13), 271-84 - https://www.usenix.org/system/files/conference/fast13/fast13-final80.pdf - - For more on why fsync does not suffice even if it works properly, see: - Roche X. Necessary step(s) to synchronize filename operations on disk. - Austin Group Defect 672, 2013-03-19 - https://austingroupbugs.net/view.php?id=672 */ - write_region_inhibit_fsync = noninteractive; } void @@ -6385,7 +6570,7 @@ syms_of_fileio (void) DEFSYM (Qcopy_file, "copy-file"); DEFSYM (Qmake_directory_internal, "make-directory-internal"); DEFSYM (Qmake_directory, "make-directory"); - DEFSYM (Qdelete_file, "delete-file"); + DEFSYM (Qdelete_file_internal, "delete-file-internal"); DEFSYM (Qfile_name_case_insensitive_p, "file-name-case-insensitive-p"); DEFSYM (Qrename_file, "rename-file"); DEFSYM (Qadd_name_to_file, "add-name-to-file"); @@ -6623,9 +6808,22 @@ file is usually more useful if it contains the deleted text. */); DEFVAR_BOOL ("write-region-inhibit-fsync", write_region_inhibit_fsync, doc: /* Non-nil means don't call fsync in `write-region'. This variable affects calls to `write-region' as well as save commands. -Setting this to nil may avoid data loss if the system loses power or -the operating system crashes. By default, it is non-nil in batch mode. */); - write_region_inhibit_fsync = 0; /* See also `init_fileio' above. */ +By default, it is non-nil. + +Although setting this to nil may avoid data loss if the system loses power, +it can be a significant performance hit in the usual case, and it doesn't +necessarily cause file-save operations to actually survive a crash. */); + + /* For more on why fsync often fails to work on today's hardware, see: + Zheng M et al. Understanding the robustness of SSDs under power fault. + 11th USENIX Conf. on File and Storage Technologies, 2013 (FAST '13), 271-84 + https://www.usenix.org/system/files/conference/fast13/fast13-final80.pdf + + For more on why fsync does not suffice even if it works properly, see: + Roche X. Necessary step(s) to synchronize filename operations on disk. + Austin Group Defect 672, 2013-03-19 + https://austingroupbugs.net/view.php?id=672 */ + write_region_inhibit_fsync = true; DEFVAR_BOOL ("delete-by-moving-to-trash", delete_by_moving_to_trash, doc: /* Specifies whether to use the system's trash can. @@ -6636,8 +6834,8 @@ This includes interactive calls to `delete-file' and delete_by_moving_to_trash = 0; DEFSYM (Qdelete_by_moving_to_trash, "delete-by-moving-to-trash"); - /* Lisp function for moving files to trash. */ - DEFSYM (Qmove_file_to_trash, "move-file-to-trash"); + /* Lisp function for interactive file delete with trashing */ + DEFSYM (Qdelete_file, "delete-file"); /* Lisp function for recursively copying directories. */ DEFSYM (Qcopy_directory, "copy-directory"); @@ -6667,7 +6865,7 @@ This includes interactive calls to `delete-file' and defsubr (&Scopy_file); defsubr (&Smake_directory_internal); defsubr (&Sdelete_directory_internal); - defsubr (&Sdelete_file); + defsubr (&Sdelete_file_internal); defsubr (&Sfile_name_case_insensitive_p); defsubr (&Srename_file); defsubr (&Sadd_name_to_file); @@ -6709,9 +6907,11 @@ This includes interactive calls to `delete-file' and #ifndef DOS_NT defsubr (&Sfile_system_info); -#endif +#endif /* DOS_NT */ #ifdef HAVE_SYNC defsubr (&Sunix_sync); -#endif +#endif /* HAVE_SYNC */ + + DEFSYM (Qif_regular, "if-regular"); } |