diff options
Diffstat (limited to 'src/stat.c')
| -rw-r--r-- | src/stat.c | 74 |
1 files changed, 51 insertions, 23 deletions
@@ -1,12 +1,14 @@ // Copyright © Tavian Barnes <tavianator@tavianator.com> // SPDX-License-Identifier: 0BSD -#include "prelude.h" #include "stat.h" + #include "atomic.h" +#include "bfs.h" #include "bfstd.h" #include "diag.h" #include "sanity.h" + #include <errno.h> #include <fcntl.h> #include <string.h> @@ -49,9 +51,11 @@ const char *bfs_stat_field_name(enum bfs_stat_field field) { return "change time"; case BFS_STAT_MTIME: return "modification time"; + case BFS_STAT_MNT_ID: + return "mount ID"; } - bfs_bug("Unrecognized stat field"); + bfs_bug("Unrecognized stat field %d", (int)field); return "???"; } @@ -62,7 +66,7 @@ int bfs_fstatat_flags(enum bfs_stat_flags flags) { ret |= AT_SYMLINK_NOFOLLOW; } -#if defined(AT_NO_AUTOMOUNT) && (!__GNU__ || __GLIBC_PREREQ(2, 35)) +#ifdef AT_NO_AUTOMOUNT ret |= AT_NO_AUTOMOUNT; #endif @@ -99,6 +103,10 @@ void bfs_stat_convert(struct bfs_stat *dest, const struct stat *src) { dest->rdev = src->st_rdev; dest->mask |= BFS_STAT_RDEV; + // No mount IDs in regular stat(), so use the dev_t as an approximation + dest->mnt_id = dest->dev; + dest->mask |= BFS_STAT_MNT_ID; + #if BFS_HAS_ST_FLAGS dest->attrs = src->st_flags; dest->mask |= BFS_STAT_ATTRS; @@ -116,6 +124,9 @@ void bfs_stat_convert(struct bfs_stat *dest, const struct stat *src) { #if BFS_HAS_ST_BIRTHTIM dest->btime = src->st_birthtim; dest->mask |= BFS_STAT_BTIME; +#elif BFS_HAS___ST_BIRTHTIM + dest->btime = src->__st_birthtim; + dest->mask |= BFS_STAT_BTIME; #elif BFS_HAS_ST_BIRTHTIMESPEC dest->btime = src->st_birthtimespec; dest->mask |= BFS_STAT_BTIME; @@ -164,6 +175,17 @@ int bfs_statx_flags(enum bfs_stat_flags flags) { return ret; } +unsigned int bfs_statx_mask(void) { + unsigned int mask = STATX_BASIC_STATS | STATX_BTIME; +#ifdef STATX_MNT_ID + mask |= STATX_MNT_ID; +#endif +#ifdef STATX_MNT_ID_UNIQUE + mask |= STATX_MNT_ID_UNIQUE; +#endif + return mask; +} + int bfs_statx_convert(struct bfs_stat *dest, const struct statx *src) { // Callers shouldn't have to check anything except the times const unsigned int guaranteed = STATX_BASIC_STATS & ~(STATX_ATIME | STATX_CTIME | STATX_MTIME); @@ -204,6 +226,18 @@ int bfs_statx_convert(struct bfs_stat *dest, const struct statx *src) { dest->attrs = src->stx_attributes; dest->mask |= BFS_STAT_ATTRS; + dest->mnt_id = dest->dev; +#ifdef STATX_MNT_ID + unsigned int mnt_mask = STATX_MNT_ID; +# ifdef STATX_MNT_ID_UNIQUE + mnt_mask |= STATX_MNT_ID_UNIQUE; +# endif + if (src->stx_mask & mnt_mask) { + dest->mnt_id = src->stx_mnt_id; + } +#endif + dest->mask |= BFS_STAT_MNT_ID; + if (src->stx_mask & STATX_ATIME) { dest->atime.tv_sec = src->stx_atime.tv_sec; dest->atime.tv_nsec = src->stx_atime.tv_nsec; @@ -235,7 +269,7 @@ int bfs_statx_convert(struct bfs_stat *dest, const struct statx *src) { * bfs_stat() implementation backed by statx(). */ static int bfs_statx_impl(int at_fd, const char *at_path, int at_flags, struct bfs_stat *buf) { - unsigned int mask = STATX_BASIC_STATS | STATX_BTIME; + unsigned int mask = bfs_statx_mask(); struct statx xbuf; int ret = bfs_statx(at_fd, at_path, at_flags, mask, &xbuf); if (ret != 0) { @@ -297,27 +331,21 @@ int bfs_stat(int at_fd, const char *at_path, enum bfs_stat_flags flags, struct b return bfs_stat_tryfollow(at_fd, at_path, at_flags, flags, buf); } - // Check __GNU__ to work around https://lists.gnu.org/archive/html/bug-hurd/2021-12/msg00001.html -#if defined(AT_EMPTY_PATH) && !__GNU__ - static atomic bool has_at_ep = true; - if (load(&has_at_ep, relaxed)) { - at_flags |= AT_EMPTY_PATH; - int ret = bfs_stat_explicit(at_fd, "", at_flags, buf); - if (ret != 0 && errno == EINVAL) { - store(&has_at_ep, false, relaxed); - } else { - return ret; - } - } -#endif - - struct stat statbuf; - if (fstat(at_fd, &statbuf) == 0) { - bfs_stat_convert(buf, &statbuf); - return 0; - } else { +#if BFS_USE_STATX + // If we have statx(), use it with AT_EMPTY_PATH for its extra features + at_flags |= AT_EMPTY_PATH; + return bfs_stat_explicit(at_fd, "", at_flags, buf); +#else + // Otherwise, just use fstat() rather than fstatat(at_fd, ""), to save + // the kernel the trouble of copying in the empty string + struct stat sb; + if (fstat(at_fd, &sb) != 0) { return -1; } + + bfs_stat_convert(buf, &sb); + return 0; +#endif } const struct timespec *bfs_stat_time(const struct bfs_stat *buf, enum bfs_stat_field field) { |