diff options
Diffstat (limited to 'gdb/nat/linux-namespaces.c')
| -rw-r--r-- | gdb/nat/linux-namespaces.c | 187 |
1 files changed, 81 insertions, 106 deletions
diff --git a/gdb/nat/linux-namespaces.c b/gdb/nat/linux-namespaces.c index 4b1fee1..f398129 100644 --- a/gdb/nat/linux-namespaces.c +++ b/gdb/nat/linux-namespaces.c @@ -97,8 +97,7 @@ linux_ns_filename (struct linux_ns *ns, int pid) static char filename[PATH_MAX]; gdb_assert (pid > 0); - xsnprintf (filename, sizeof (filename), "/proc/%d/ns/%s", pid, - ns->filename); + xsnprintf (filename, sizeof (filename), "/proc/%d/ns/%s", pid, ns->filename); return filename; } @@ -109,15 +108,9 @@ linux_ns_filename (struct linux_ns *ns, int pid) static struct linux_ns * linux_ns_get_namespace (enum linux_ns_type type) { - static struct linux_ns namespaces[NUM_LINUX_NS_TYPES] = - { - { "ipc" }, - { "mnt" }, - { "net" }, - { "pid" }, - { "user" }, - { "uts" }, - }; + static struct linux_ns namespaces[NUM_LINUX_NS_TYPES] = { + { "ipc" }, { "mnt" }, { "net" }, { "pid" }, { "user" }, { "uts" }, + }; struct linux_ns *ns; gdb_assert (type >= 0 && type < NUM_LINUX_NS_TYPES); @@ -220,58 +213,57 @@ linux_ns_same (pid_t pid, enum linux_ns_type type) /* Mount namespace helper message types. */ enum mnsh_msg_type - { - /* A communication error occurred. Receipt of this message +{ + /* A communication error occurred. Receipt of this message by either end will cause an assertion failure in the main process. */ - MNSH_MSG_ERROR, + MNSH_MSG_ERROR, - /* Requests, sent from the main process to the helper. */ + /* Requests, sent from the main process to the helper. */ - /* A request that the helper call setns. Arguments should + /* A request that the helper call setns. Arguments should be passed in FD and INT1. Helper should respond with a MNSH_RET_INT. */ - MNSH_REQ_SETNS, + MNSH_REQ_SETNS, - /* A request that the helper call open. Arguments should + /* A request that the helper call open. Arguments should be passed in BUF, INT1 and INT2. The filename (in BUF) should include a terminating NUL character. The helper should respond with a MNSH_RET_FD. */ - MNSH_REQ_OPEN, + MNSH_REQ_OPEN, - /* A request that the helper call unlink. The single + /* A request that the helper call unlink. The single argument (the filename) should be passed in BUF, and should include a terminating NUL character. The helper should respond with a MNSH_RET_INT. */ - MNSH_REQ_UNLINK, + MNSH_REQ_UNLINK, - /* A request that the helper call readlink. The single + /* A request that the helper call readlink. The single argument (the filename) should be passed in BUF, and should include a terminating NUL character. The helper should respond with a MNSH_RET_INTSTR. */ - MNSH_REQ_READLINK, + MNSH_REQ_READLINK, - /* Responses, sent to the main process from the helper. */ + /* Responses, sent to the main process from the helper. */ - /* Return an integer in INT1 and errno in INT2. */ - MNSH_RET_INT, + /* Return an integer in INT1 and errno in INT2. */ + MNSH_RET_INT, - /* Return a file descriptor in FD if one was opened or an + /* Return a file descriptor in FD if one was opened or an integer in INT1 otherwise. Return errno in INT2. */ - MNSH_RET_FD, + MNSH_RET_FD, - /* Return an integer in INT1, errno in INT2, and optionally + /* Return an integer in INT1, errno in INT2, and optionally some data in BUF. */ - MNSH_RET_INTSTR, - }; + MNSH_RET_INTSTR, +}; /* Print a string representation of a message using debug_printf. This function is not async-signal-safe so should never be called from the helper. */ static void -mnsh_debug_print_message (enum mnsh_msg_type type, - int fd, int int1, int int2, +mnsh_debug_print_message (enum mnsh_msg_type type, int fd, int int1, int int2, const void *buf, int bufsiz) { gdb_byte *c = (gdb_byte *) buf; @@ -334,9 +326,8 @@ static void mnsh_maybe_mourn_peer (void); main process and the helper so must be async-signal-safe. */ static ssize_t -mnsh_send_message (int sock, enum mnsh_msg_type type, - int fd, int int1, int int2, - const void *buf, int bufsiz) +mnsh_send_message (int sock, enum mnsh_msg_type type, int fd, int int1, + int int2, const void *buf, int bufsiz) { struct msghdr msg; struct iovec iov[4]; @@ -363,7 +354,7 @@ mnsh_send_message (int sock, enum mnsh_msg_type type, memcpy (iov[3].iov_base, buf, bufsiz); iov[3].iov_len = bufsiz; - msg.msg_iovlen ++; + msg.msg_iovlen++; } /* Attach FD if supplied. */ @@ -409,9 +400,8 @@ mnsh_send_message (int sock, enum mnsh_msg_type type, async-signal-safe. */ static ssize_t -mnsh_recv_message (int sock, enum mnsh_msg_type *type, - int *fd, int *int1, int *int2, - void *buf, int bufsiz) +mnsh_recv_message (int sock, enum mnsh_msg_type *type, int *fd, int *int1, + int *int2, void *buf, int bufsiz) { struct msghdr msg; struct iovec iov[4]; @@ -469,10 +459,8 @@ mnsh_recv_message (int sock, enum mnsh_msg_type *type, /* Unpack the file descriptor if supplied. */ cmsg = CMSG_FIRSTHDR (&msg); - if (cmsg != NULL - && cmsg->cmsg_len == CMSG_LEN (sizeof (int)) - && cmsg->cmsg_level == SOL_SOCKET - && cmsg->cmsg_type == SCM_RIGHTS) + if (cmsg != NULL && cmsg->cmsg_len == CMSG_LEN (sizeof (int)) + && cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) memcpy (fd, CMSG_DATA (cmsg), sizeof (int)); else *fd = -1; @@ -494,15 +482,12 @@ mnsh_recv_message (int sock, enum mnsh_msg_type *type, #define mnsh_return_int(sock, result, error) \ mnsh_send_message (sock, MNSH_RET_INT, -1, result, error, NULL, 0) -#define mnsh_return_fd(sock, fd, error) \ - mnsh_send_message (sock, MNSH_RET_FD, \ - (fd) < 0 ? -1 : (fd), \ - (fd) < 0 ? (fd) : 0, \ - error, NULL, 0) +#define mnsh_return_fd(sock, fd, error) \ + mnsh_send_message (sock, MNSH_RET_FD, (fd) < 0 ? -1 : (fd), \ + (fd) < 0 ? (fd) : 0, error, NULL, 0) #define mnsh_return_intstr(sock, result, buf, bufsiz, error) \ - mnsh_send_message (sock, MNSH_RET_INTSTR, -1, result, error, \ - buf, bufsiz) + mnsh_send_message (sock, MNSH_RET_INTSTR, -1, result, error, buf, bufsiz) /* Handle a MNSH_REQ_SETNS message. Must be async-signal-safe. */ @@ -517,8 +502,7 @@ mnsh_handle_setns (int sock, int fd, int nstype) /* Handle a MNSH_REQ_OPEN message. Must be async-signal-safe. */ static ssize_t -mnsh_handle_open (int sock, const char *filename, - int flags, mode_t mode) +mnsh_handle_open (int sock, const char *filename, int flags, mode_t mode) { scoped_fd fd = gdb_open_cloexec (filename, flags, mode); return mnsh_return_fd (sock, fd.get (), errno); @@ -542,9 +526,7 @@ mnsh_handle_readlink (int sock, const char *filename) char buf[PATH_MAX]; int len = readlink (filename, buf, sizeof (buf)); - return mnsh_return_intstr (sock, len, - buf, len < 0 ? 0 : len, - errno); + return mnsh_return_intstr (sock, len, buf, len < 0 ? 0 : len, errno); } /* The helper process. Never returns. Must be async-signal-safe. */ @@ -561,9 +543,8 @@ mnsh_main (int sock) char buf[PATH_MAX]; ssize_t size, response = -1; - size = mnsh_recv_message (sock, &type, - &fd, &int1, &int2, - buf, sizeof (buf)); + size = mnsh_recv_message (sock, &type, &fd, &int1, &int2, buf, + sizeof (buf)); if (size >= 0 && size < sizeof (buf)) { @@ -604,8 +585,7 @@ mnsh_main (int sock) if (size < 0) size = 0; - mnsh_send_message (sock, MNSH_MSG_ERROR, - -1, int1, int2, buf, size); + mnsh_send_message (sock, MNSH_MSG_ERROR, -1, int1, int2, buf, size); } } } @@ -732,23 +712,23 @@ mnsh_maybe_mourn_peer (void) else if (pid == -1) { if (errno == ECHILD) - warning (_("mount namespace helper vanished?")); + warning (_ ("mount namespace helper vanished?")); else - internal_warning (_("unhandled error %d"), errno); + internal_warning (_ ("unhandled error %d"), errno); } else if (pid == helper->pid) { if (WIFEXITED (status)) - warning (_("mount namespace helper exited with status %d"), + warning (_ ("mount namespace helper exited with status %d"), WEXITSTATUS (status)); else if (WIFSIGNALED (status)) - warning (_("mount namespace helper killed by signal %d"), + warning (_ ("mount namespace helper killed by signal %d"), WTERMSIG (status)); else - internal_warning (_("unhandled status %d"), status); + internal_warning (_ ("unhandled status %d"), status); } else - internal_warning (_("unknown pid %d"), pid); + internal_warning (_ ("unknown pid %d"), pid); /* Something unrecoverable happened. */ helper->pid = -1; @@ -758,20 +738,19 @@ mnsh_maybe_mourn_peer (void) /* Shortcuts for sending messages to the helper. */ #define mnsh_send_setns(helper, fd, nstype) \ - mnsh_send_message (helper->sock, MNSH_REQ_SETNS, fd, nstype, 0, \ - NULL, 0) + mnsh_send_message (helper->sock, MNSH_REQ_SETNS, fd, nstype, 0, NULL, 0) -#define mnsh_send_open(helper, filename, flags, mode) \ - mnsh_send_message (helper->sock, MNSH_REQ_OPEN, -1, flags, mode, \ - filename, strlen (filename) + 1) +#define mnsh_send_open(helper, filename, flags, mode) \ + mnsh_send_message (helper->sock, MNSH_REQ_OPEN, -1, flags, mode, filename, \ + strlen (filename) + 1) -#define mnsh_send_unlink(helper, filename) \ - mnsh_send_message (helper->sock, MNSH_REQ_UNLINK, -1, 0, 0, \ - filename, strlen (filename) + 1) +#define mnsh_send_unlink(helper, filename) \ + mnsh_send_message (helper->sock, MNSH_REQ_UNLINK, -1, 0, 0, filename, \ + strlen (filename) + 1) -#define mnsh_send_readlink(helper, filename) \ - mnsh_send_message (helper->sock, MNSH_REQ_READLINK, -1, 0, 0, \ - filename, strlen (filename) + 1) +#define mnsh_send_readlink(helper, filename) \ + mnsh_send_message (helper->sock, MNSH_REQ_READLINK, -1, 0, 0, filename, \ + strlen (filename) + 1) /* Receive a message from the helper. Issue an assertion failure if the message isn't a correctly-formatted MNSH_RET_INT. Set RESULT @@ -786,9 +765,8 @@ mnsh_recv_int (struct linux_mnsh *helper, int *result, int *error) ssize_t size; int fd; - size = mnsh_recv_message (helper->sock, &type, &fd, - result, error, - buf, sizeof (buf)); + size = mnsh_recv_message (helper->sock, &type, &fd, result, error, buf, + sizeof (buf)); if (size < 0) return -1; @@ -812,9 +790,8 @@ mnsh_recv_fd (struct linux_mnsh *helper, int *fd, int *error) ssize_t size; int result; - size = mnsh_recv_message (helper->sock, &type, fd, - &result, error, - buf, sizeof (buf)); + size = mnsh_recv_message (helper->sock, &type, fd, &result, error, buf, + sizeof (buf)); if (size < 0) return -1; @@ -837,17 +814,15 @@ mnsh_recv_fd (struct linux_mnsh *helper, int *fd, int *error) Set errno and return -1 on error. */ static ssize_t -mnsh_recv_intstr (struct linux_mnsh *helper, - int *result, int *error, +mnsh_recv_intstr (struct linux_mnsh *helper, int *result, int *error, void *buf, int bufsiz) { enum mnsh_msg_type type; ssize_t size; int fd; - size = mnsh_recv_message (helper->sock, &type, &fd, - result, error, - buf, bufsiz); + size + = mnsh_recv_message (helper->sock, &type, &fd, result, error, buf, bufsiz); if (size < 0) return -1; @@ -861,18 +836,18 @@ mnsh_recv_intstr (struct linux_mnsh *helper, /* Return values for linux_mntns_access_fs. */ enum mnsh_fs_code - { - /* Something went wrong, errno is set. */ - MNSH_FS_ERROR = -1, +{ + /* Something went wrong, errno is set. */ + MNSH_FS_ERROR = -1, - /* The main process is in the correct mount namespace. + /* The main process is in the correct mount namespace. The caller should access the filesystem directly. */ - MNSH_FS_DIRECT, + MNSH_FS_DIRECT, - /* The helper is in the correct mount namespace. + /* The helper is in the correct mount namespace. The caller should access the filesystem via the helper. */ - MNSH_FS_HELPER - }; + MNSH_FS_HELPER +}; /* Return a value indicating how the caller should access the mount namespace of process PID. */ @@ -898,11 +873,11 @@ linux_mntns_access_fs (pid_t pid) return MNSH_FS_ERROR; SCOPE_EXIT - { - int save_errno = errno; - close (fd); - errno = save_errno; - }; + { + int save_errno = errno; + close (fd); + errno = save_errno; + }; if (fstat (fd, &sb) != 0) return MNSH_FS_ERROR; @@ -948,8 +923,8 @@ linux_mntns_access_fs (pid_t pid) /* See nat/linux-namespaces.h. */ int -linux_mntns_open_cloexec (pid_t pid, const char *filename, - int flags, mode_t mode) +linux_mntns_open_cloexec (pid_t pid, const char *filename, int flags, + mode_t mode) { enum mnsh_fs_code access = linux_mntns_access_fs (pid); struct linux_mnsh *helper; @@ -1015,8 +990,8 @@ linux_mntns_unlink (pid_t pid, const char *filename) /* See nat/linux-namespaces.h. */ ssize_t -linux_mntns_readlink (pid_t pid, const char *filename, - char *buf, size_t bufsiz) +linux_mntns_readlink (pid_t pid, const char *filename, char *buf, + size_t bufsiz) { enum mnsh_fs_code access = linux_mntns_access_fs (pid); struct linux_mnsh *helper; |