diff options
Diffstat (limited to 'shared/os-compatibility.c')
| -rw-r--r-- | shared/os-compatibility.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/shared/os-compatibility.c b/shared/os-compatibility.c index 4f96dd4c..611e7c80 100644 --- a/shared/os-compatibility.c +++ b/shared/os-compatibility.c @@ -132,6 +132,12 @@ create_tmpfile_cloexec(char *tmpname) * The file is suitable for buffer sharing between processes by * transmitting the file descriptor over Unix sockets using the * SCM_RIGHTS methods. + * + * If the C library implements posix_fallocate(), it is used to + * guarantee that disk space is available for the file at the + * given size. If disk space is insufficent, errno is set to ENOSPC. + * If posix_fallocate() is not supported, program may receive + * SIGBUS on accessing mmap()'ed file contents instead. */ int os_create_anonymous_file(off_t size) @@ -140,6 +146,7 @@ os_create_anonymous_file(off_t size) const char *path; char *name; int fd; + int ret; path = getenv("XDG_RUNTIME_DIR"); if (!path) { @@ -161,10 +168,20 @@ os_create_anonymous_file(off_t size) if (fd < 0) return -1; - if (ftruncate(fd, size) < 0) { +#ifdef HAVE_POSIX_FALLOCATE + ret = posix_fallocate(fd, 0, size); + if (ret != 0) { close(fd); + errno = ret; return -1; } +#else + ret = ftruncate(fd, size); + if (ret < 0) { + close(fd); + return -1; + } +#endif return fd; } |