diff options
Diffstat (limited to 'src/common/util.c')
-rw-r--r-- | src/common/util.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/src/common/util.c b/src/common/util.c index cb8ff85b40..8cb013e18a 100644 --- a/src/common/util.c +++ b/src/common/util.c @@ -3264,8 +3264,11 @@ format_hex_number_for_helper_exit_status(unsigned int x, char *buf, * in the processs of starting the child process did the failure occur (see * CHILD_STATE_* macros for definition), and SAVED_ERRNO is the value of * errno when the failure occurred. + * + * On success return the number of characters added to hex_errno, not counting + * the terminating NUL; return -1 on error. */ -void +int format_helper_exit_status(unsigned char child_state, int saved_errno, char *hex_errno) { @@ -3273,6 +3276,7 @@ format_helper_exit_status(unsigned char child_state, int saved_errno, int written, left; char *cur; size_t i; + int res = -1; /* Fill hex_errno with spaces, and a trailing newline (memset may not be signal handler safe, so we can't use it) */ @@ -3343,6 +3347,8 @@ format_helper_exit_status(unsigned char child_state, int saved_errno, *cur++ = '\n'; *cur++ = '\0'; + res = cur - hex_errno - 1; + goto done; err: @@ -3353,7 +3359,7 @@ format_helper_exit_status(unsigned char child_state, int saved_errno, *hex_errno = '\0'; done: - return; + return res; } /* Maximum number of file descriptors, if we cannot get it via sysconf() */ @@ -3695,15 +3701,20 @@ tor_spawn_background(const char *const filename, const char **argv, child_state = CHILD_STATE_FAILEXEC; error: - /* XXX: are we leaking fds from the pipe? */ + { + /* XXX: are we leaking fds from the pipe? */ + int n; - format_helper_exit_status(child_state, errno, hex_errno); + n = format_helper_exit_status(child_state, errno, hex_errno); - /* Write the error message. GCC requires that we check the return - value, but there is nothing we can do if it fails */ - /* TODO: Don't use STDOUT, use a pipe set up just for this purpose */ - nbytes = write(STDOUT_FILENO, error_message, error_message_length); - nbytes = write(STDOUT_FILENO, hex_errno, sizeof(hex_errno)); + if (n >= 0) { + /* Write the error message. GCC requires that we check the return + value, but there is nothing we can do if it fails */ + /* TODO: Don't use STDOUT, use a pipe set up just for this purpose */ + nbytes = write(STDOUT_FILENO, error_message, error_message_length); + nbytes = write(STDOUT_FILENO, hex_errno, n); + } + } (void) nbytes; |