X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Futil.c;h=a7aec5c54f53114b991084277055901e77f74a96;hb=1b99214789101976d6bbf75c351279584b071998;hp=4a3e35f356508964f963075a09de8c909c207c4c;hpb=966bff2660a13c82b70a1e1ac4f1a48bb33d7f7e;p=elogind.git diff --git a/src/shared/util.c b/src/shared/util.c index 4a3e35f35..a7aec5c54 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -54,6 +54,7 @@ #include #include #include +#include #include #include #include @@ -803,7 +804,7 @@ char *strappend(const char *s, const char *suffix) { return strnappend(s, suffix, suffix ? strlen(suffix) : 0); } -int readlink_malloc(const char *p, char **ret) { +int readlinkat_malloc(int fd, const char *p, char **ret) { size_t l = 100; int r; @@ -818,7 +819,7 @@ int readlink_malloc(const char *p, char **ret) { if (!c) return -ENOMEM; - n = readlink(p, c, l-1); + n = readlinkat(fd, p, c, l-1); if (n < 0) { r = -errno; free(c); @@ -836,6 +837,10 @@ int readlink_malloc(const char *p, char **ret) { } } +int readlink_malloc(const char *p, char **ret) { + return readlinkat_malloc(AT_FDCWD, p, ret); +} + int readlink_and_make_absolute(const char *p, char **r) { _cleanup_free_ char *target = NULL; char *k; @@ -1377,38 +1382,46 @@ bool ignore_file(const char *filename) { } int fd_nonblock(int fd, bool nonblock) { - int flags; + int flags, nflags; assert(fd >= 0); - if ((flags = fcntl(fd, F_GETFL, 0)) < 0) + flags = fcntl(fd, F_GETFL, 0); + if (flags < 0) return -errno; if (nonblock) - flags |= O_NONBLOCK; + nflags = flags | O_NONBLOCK; else - flags &= ~O_NONBLOCK; + nflags = flags & ~O_NONBLOCK; - if (fcntl(fd, F_SETFL, flags) < 0) + if (nflags == flags) + return 0; + + if (fcntl(fd, F_SETFL, nflags) < 0) return -errno; return 0; } int fd_cloexec(int fd, bool cloexec) { - int flags; + int flags, nflags; assert(fd >= 0); - if ((flags = fcntl(fd, F_GETFD, 0)) < 0) + flags = fcntl(fd, F_GETFD, 0); + if (flags < 0) return -errno; if (cloexec) - flags |= FD_CLOEXEC; + nflags = flags | FD_CLOEXEC; else - flags &= ~FD_CLOEXEC; + nflags = flags & ~FD_CLOEXEC; + + if (nflags == flags) + return 0; - if (fcntl(fd, F_SETFD, flags) < 0) + if (fcntl(fd, F_SETFD, nflags) < 0) return -errno; return 0; @@ -3994,24 +4007,16 @@ int fd_wait_for_event(int fd, int event, usec_t t) { int fopen_temporary(const char *path, FILE **_f, char **_temp_path) { FILE *f; char *t; - const char *fn; - size_t k; int fd; assert(path); assert(_f); assert(_temp_path); - t = new(char, strlen(path) + 1 + 6 + 1); + t = strappend(path, ".XXXXXX"); if (!t) return -ENOMEM; - fn = basename(path); - k = fn - path; - memcpy(t, path, k); - t[k] = '.'; - stpcpy(stpcpy(t+k+1, fn), "XXXXXX"); - fd = mkostemp_safe(t, O_WRONLY|O_CLOEXEC); if (fd < 0) { free(t); @@ -4119,60 +4124,6 @@ int vt_disallocate(const char *name) { return 0; } -int copy_file(const char *from, const char *to, int flags) { - _cleanup_close_ int fdf = -1; - int r, fdt; - - assert(from); - assert(to); - - fdf = open(from, O_RDONLY|O_CLOEXEC|O_NOCTTY); - if (fdf < 0) - return -errno; - - fdt = open(to, flags|O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY, 0644); - if (fdt < 0) - return -errno; - - for (;;) { - char buf[PIPE_BUF]; - ssize_t n, k; - - n = read(fdf, buf, sizeof(buf)); - if (n < 0) { - r = -errno; - - close_nointr(fdt); - unlink(to); - - return r; - } - - if (n == 0) - break; - - errno = 0; - k = loop_write(fdt, buf, n, false); - if (n != k) { - r = k < 0 ? k : (errno ? -errno : -EIO); - - close_nointr(fdt); - unlink(to); - - return r; - } - } - - r = close_nointr(fdt); - - if (r < 0) { - unlink(to); - return r; - } - - return 0; -} - int symlink_atomic(const char *from, const char *to) { char *x; _cleanup_free_ char *t; @@ -5498,6 +5449,7 @@ const char *draw_special_char(DrawSpecialChar ch) { [DRAW_TRIANGULAR_BULLET] = "\342\200\243", /* ‣ */ [DRAW_BLACK_CIRCLE] = "\342\227\217", /* ● */ [DRAW_ARROW] = "\342\206\222", /* → */ + [DRAW_DASH] = "\342\200\223", /* – */ }, /* ASCII fallback */ { @@ -5508,6 +5460,7 @@ const char *draw_special_char(DrawSpecialChar ch) { [DRAW_TRIANGULAR_BULLET] = ">", [DRAW_BLACK_CIRCLE] = "*", [DRAW_ARROW] = "->", + [DRAW_DASH] = "-", } }; @@ -6494,3 +6447,224 @@ int update_reboot_param_file(const char *param) { return r; } + +int umount_recursive(const char *prefix, int flags) { + bool again; + int n = 0, r; + + /* Try to umount everything recursively below a + * directory. Also, take care of stacked mounts, and keep + * unmounting them until they are gone. */ + + do { + _cleanup_fclose_ FILE *proc_self_mountinfo = NULL; + + again = false; + r = 0; + + proc_self_mountinfo = fopen("/proc/self/mountinfo", "re"); + if (!proc_self_mountinfo) + return -errno; + + for (;;) { + _cleanup_free_ char *path = NULL, *p = NULL; + int k; + + k = fscanf(proc_self_mountinfo, + "%*s " /* (1) mount id */ + "%*s " /* (2) parent id */ + "%*s " /* (3) major:minor */ + "%*s " /* (4) root */ + "%ms " /* (5) mount point */ + "%*s" /* (6) mount options */ + "%*[^-]" /* (7) optional fields */ + "- " /* (8) separator */ + "%*s " /* (9) file system type */ + "%*s" /* (10) mount source */ + "%*s" /* (11) mount options 2 */ + "%*[^\n]", /* some rubbish at the end */ + &path); + if (k != 1) { + if (k == EOF) + break; + + continue; + } + + p = cunescape(path); + if (!p) + return -ENOMEM; + + if (!path_startswith(p, prefix)) + continue; + + if (umount2(p, flags) < 0) { + r = -errno; + continue; + } + + again = true; + n++; + + break; + } + + } while (again); + + return r ? r : n; +} + +int bind_remount_recursive(const char *prefix, bool ro) { + _cleanup_set_free_free_ Set *done = NULL; + _cleanup_free_ char *cleaned = NULL; + int r; + + /* Recursively remount a directory (and all its submounts) + * read-only or read-write. If the directory is already + * mounted, we reuse the mount and simply mark it + * MS_BIND|MS_RDONLY (or remove the MS_RDONLY for read-write + * operation). If it isn't we first make it one. Afterwards we + * apply MS_BIND|MS_RDONLY (or remove MS_RDONLY) to all + * submounts we can access, too. When mounts are stacked on + * the same mount point we only care for each individual + * "top-level" mount on each point, as we cannot + * influence/access the underlying mounts anyway. We do not + * have any effect on future submounts that might get + * propagated, they migt be writable. This includes future + * submounts that have been triggered via autofs. */ + + cleaned = strdup(prefix); + if (!cleaned) + return -ENOMEM; + + path_kill_slashes(cleaned); + + done = set_new(string_hash_func, string_compare_func); + if (!done) + return -ENOMEM; + + for (;;) { + _cleanup_fclose_ FILE *proc_self_mountinfo = NULL; + _cleanup_set_free_free_ Set *todo = NULL; + bool top_autofs = false; + char *x; + + todo = set_new(string_hash_func, string_compare_func); + if (!todo) + return -ENOMEM; + + proc_self_mountinfo = fopen("/proc/self/mountinfo", "re"); + if (!proc_self_mountinfo) + return -errno; + + for (;;) { + _cleanup_free_ char *path = NULL, *p = NULL, *type = NULL; + int k; + + k = fscanf(proc_self_mountinfo, + "%*s " /* (1) mount id */ + "%*s " /* (2) parent id */ + "%*s " /* (3) major:minor */ + "%*s " /* (4) root */ + "%ms " /* (5) mount point */ + "%*s" /* (6) mount options (superblock) */ + "%*[^-]" /* (7) optional fields */ + "- " /* (8) separator */ + "%ms " /* (9) file system type */ + "%*s" /* (10) mount source */ + "%*s" /* (11) mount options (bind mount) */ + "%*[^\n]", /* some rubbish at the end */ + &path, + &type); + if (k != 2) { + if (k == EOF) + break; + + continue; + } + + p = cunescape(path); + if (!p) + return -ENOMEM; + + /* Let's ignore autofs mounts. If they aren't + * triggered yet, we want to avoid triggering + * them, as we don't make any guarantees for + * future submounts anyway. If they are + * already triggered, then we will find + * another entry for this. */ + if (streq(type, "autofs")) { + top_autofs = top_autofs || path_equal(cleaned, p); + continue; + } + + if (path_startswith(p, cleaned) && + !set_contains(done, p)) { + + r = set_consume(todo, p); + p = NULL; + + if (r == -EEXIST) + continue; + if (r < 0) + return r; + } + } + + /* If we have no submounts to process anymore and if + * the root is either already done, or an autofs, we + * are done */ + if (set_isempty(todo) && + (top_autofs || set_contains(done, cleaned))) + return 0; + + if (!set_contains(done, cleaned) && + !set_contains(todo, cleaned)) { + /* The prefix directory itself is not yet a + * mount, make it one. */ + if (mount(cleaned, cleaned, NULL, MS_BIND|MS_REC, NULL) < 0) + return -errno; + + if (mount(NULL, prefix, NULL, MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) + return -errno; + + x = strdup(cleaned); + if (!x) + return -ENOMEM; + + r = set_consume(done, x); + if (r < 0) + return r; + } + + while ((x = set_steal_first(todo))) { + + r = set_consume(done, x); + if (r == -EEXIST) + continue; + if (r < 0) + return r; + + if (mount(NULL, x, NULL, MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) { + + /* Deal with mount points that are + * obstructed by a later mount */ + + if (errno != ENOENT) + return -errno; + } + + } + } +} + +int fflush_and_check(FILE *f) { + + errno = 0; + fflush(f); + + if (ferror(f)) + return errno ? -errno : -EIO; + + return 0; +}