nihilist/tor
1
0
Fork 0
mirror of https://gitlab.torproject.org/tpo/core/tor.git synced 2024-11-10 21:23:58 +01:00
Code Issues Packages Projects Releases Wiki Activity

options_act_reversible: add more comments to explain ordering

Browse Source
This commit is contained in:
Nick Mathewson 2019-11-20 09:49:25 -05:00
parent a3d06179ce
commit b33f3c960d
1 changed files with 20 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/app/config/config.c
View File

@ -1902,8 +1902,10 @@ options_rollback_log_transaction(log_transaction_t *xn)
tor_free(xn); tor_free(xn);
} }
/** Fetch the active option list, and take actions based on it. All of the /**
* things we do should survive being done repeatedly. If present, * Fetch the active option list, and take actions based on it. All of
* the things we do in this function should survive being done
* repeatedly, OR be done only once when starting Tor. If present,
* <b>old_options</b> contains the previous value of the options. * <b>old_options</b> contains the previous value of the options.
* *
* This function is only truly "reversible" _after_ the first time it * This function is only truly "reversible" _after_ the first time it
@ -1924,9 +1926,19 @@ options_act_reversible,(const or_options_t *old_options, char **msg))
listener_transaction_t *listener_transaction = NULL; listener_transaction_t *listener_transaction = NULL;
int r = -1; int r = -1;
/* The ordering of actions in this function is not free, sadly.
*
* First of all, we _must_ daemonize before we take all kinds of
* initialization actions, since they need to happen in the
* subprocess.
*/
if (options_act_once_on_startup(msg) < 0) if (options_act_once_on_startup(msg) < 0)
goto rollback; goto rollback;
/* Once we've handled most of once-off initialization, we need to
* open our listeners before we switch IDs. (If we open listeners first,
* we might not be able to bind to low ports.)
*/
listener_transaction = options_start_listener_transaction(old_options, msg); listener_transaction = options_start_listener_transaction(old_options, msg);
if (listener_transaction == NULL) if (listener_transaction == NULL)
goto rollback; goto rollback;
@ -1934,7 +1946,13 @@ options_act_reversible,(const or_options_t *old_options, char **msg))
if (first_time) { if (first_time) {
if (options_switch_id(msg) < 0) if (options_switch_id(msg) < 0)
goto done; goto done;
}
/* On the other hand, we need to touch the file system _after_ we
* switch IDs: otherwise, we'll be making directories and opening files
* with the wrong permissions.
*/
if (first_time) {
if (options_create_directories(msg) < 0) if (options_create_directories(msg) < 0)
goto done; goto done;
} }