commit ce9b1015741b663e4f1dbd2923886aedd00c7094 Author: teor teor@torproject.org Date: Wed Apr 10 15:57:54 2019 +1000
bwauth: update measured bandwidth file comments
We forgot to update function header comments and code comments when we made changes in 0.3.5.1-alpha and later.
Closes 30112. --- src/feature/dirauth/bwauth.c | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-)
diff --git a/src/feature/dirauth/bwauth.c b/src/feature/dirauth/bwauth.c index 1cfd8119d..e60c8b86b 100644 --- a/src/feature/dirauth/bwauth.c +++ b/src/feature/dirauth/bwauth.c @@ -199,9 +199,32 @@ dirserv_get_credible_bandwidth_kb(const routerinfo_t *ri) }
/** - * Read the measured bandwidth list file, apply it to the list of - * vote_routerstatus_t and store all the headers in <b>bw_file_headers</b>. + * Read the measured bandwidth list <b>from_file</b>: + * - store all the headers in <b>bw_file_headers</b>, + * - apply bandwidth lines to the list of vote_routerstatus_t in + * <b>routerstatuses</b>, + * - cache bandwidth lines for dirserv_get_bandwidth_for_router(), + * - expire old entries in the measured bandwidth cache, and + * - store the DIGEST_SHA256 of the contents of the file in <b>digest_out</b>. + * * Returns -1 on error, 0 otherwise. + * + * If the file can't be read, or is empty: + * - <b>bw_file_headers</b> is empty, + * - <b>routerstatuses</b> is not modified, + * - the measured bandwidth cache is not modified, and + * - <b>digest_out</b> is the zero-byte digest. + * + * Otherwise, if there is an error later in the file: + * - <b>bw_file_headers</b> contains all the headers up to the error, + * - <b>routerstatuses</b> is updated with all the relay lines up to the error, + * - the measured bandwidth cache is updated with all the relay lines up to + * the error, + * - if the timestamp is valid and recent, old entries in the measured + * bandwidth cache are expired, and + * - <b>digest_out</b> is the digest up to the first read error (if any). + * The digest is taken over all the readable file contents, even if the + * file is outdated or unparseable. */ int dirserv_read_measured_bandwidths(const char *from_file, @@ -223,15 +246,12 @@ dirserv_read_measured_bandwidths(const char *from_file, size_t n = 0; crypto_digest_t *digest = crypto_digest256_new(DIGEST_SHA256);
- /* Initialise line, so that we can't possibly run off the end. */ - if (fp == NULL) { log_warn(LD_CONFIG, "Can't open bandwidth file at configured location: %s", from_file); goto err; }
- /* If fgets fails, line is either unmodified, or indeterminate. */ if (tor_getline(&line,&n,fp) <= 0) { log_warn(LD_DIRSERV, "Empty bandwidth file"); goto err; @@ -345,6 +365,9 @@ dirserv_read_measured_bandwidths(const char *from_file, * the header block yet. If we encounter an incomplete bw line, return -1 but * don't warn since there could be additional header lines coming. If we * encounter a proper bw line, return 0 (and we got past the headers). + * + * If the line contains "vote=0", stop parsing it, and return -1, so that the + * line is ignored during voting. */ STATIC int measured_bw_line_parse(measured_bw_line_t *out, const char *orig_line,