diff options
Diffstat (limited to 'src/basic/fd-util.c')
| -rw-r--r-- | src/basic/fd-util.c | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/src/basic/fd-util.c b/src/basic/fd-util.c index 8ae79fb69..21c9d8b87 100644 --- a/src/basic/fd-util.c +++ b/src/basic/fd-util.c @@ -431,7 +431,6 @@ int move_fd(int from, int to, int cloexec) { int acquire_data_fd(const void *data, size_t size, unsigned flags) { - char procfs_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int)]; _cleanup_close_pair_ int pipefds[2] = { -1, -1 }; char pattern[] = "/dev/shm/data-fd-XXXXXX"; _cleanup_close_ int fd = -1; @@ -541,12 +540,7 @@ try_dev_shm: return -EIO; /* Let's reopen the thing, in order to get an O_RDONLY fd for the original O_RDWR one */ - xsprintf(procfs_path, "/proc/self/fd/%i", fd); - r = open(procfs_path, O_RDONLY|O_CLOEXEC); - if (r < 0) - return -errno; - - return r; + return fd_reopen(fd, O_RDONLY|O_CLOEXEC); } try_dev_shm_without_o_tmpfile: @@ -729,3 +723,22 @@ finish: return r; } + +int fd_reopen(int fd, int flags) { + char procfs_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int)]; + int new_fd; + + /* Reopens the specified fd with new flags. This is useful for convert an O_PATH fd into a regular one, or to + * turn O_RDWR fds into O_RDONLY fds. + * + * This doesn't work on sockets (since they cannot be open()ed, ever). + * + * This implicitly resets the file read index to 0. */ + + xsprintf(procfs_path, "/proc/self/fd/%i", fd); + new_fd = open(procfs_path, flags); + if (new_fd < 0) + return -errno; + + return new_fd; +} |