commit 6da31ec4848b23db4b923ff5141c24b82f466c8d
Author: Nick Mathewson <nickm(a)torproject.org>
Date: Fri May 5 10:48:02 2017 -0400
consdiffmgr: Extract the code for compressing and storing
We're going to use this for consensuses too.
---
src/or/consdiffmgr.c | 142 +++++++++++++++++++++++++++++++++++----------------
1 file changed, 99 insertions(+), 43 deletions(-)
diff --git a/src/or/consdiffmgr.c b/src/or/consdiffmgr.c
index d478101..b108c80 100644
--- a/src/or/consdiffmgr.c
+++ b/src/or/consdiffmgr.c
@@ -1072,6 +1072,91 @@ typedef struct compressed_result_t {
} compressed_result_t;
/**
+ * Compress the bytestring <b>input</b> of length <b>len</b> using the
+ * <n>n_methods</b> compression methods listed in the array <b>methods</b>.
+ *
+ * For each successful compression, set the fields in the <b>results_out</b>
+ * array in the position corresponding to the compression method. Use
+ * <b>labels_in</b> as a basis for the labels of the result.
+ *
+ * Return 0 if all compression succeeded; -1 if any failed.
+ */
+static int
+compress_multiple(compressed_result_t *results_out, int n_methods,
+ const compress_method_t *methods,
+ const uint8_t *input, size_t len,
+ const config_line_t *labels_in)
+{
+ int rv = 0;
+ int i;
+ for (i = 0; i < n_methods; ++i) {
+ compress_method_t method = methods[i];
+ const char *methodname = compression_method_get_name(method);
+ char *result;
+ size_t sz;
+ if (0 == tor_compress(&result, &sz, (const char*)input, len, method)) {
+ results_out[i].body = (uint8_t*)result;
+ results_out[i].bodylen = sz;
+ results_out[i].labels = config_lines_dup(labels_in);
+ cdm_labels_prepend_sha3(&results_out[i].labels, LABEL_SHA3_DIGEST,
+ results_out[i].body,
+ results_out[i].bodylen);
+ config_line_prepend(&results_out[i].labels,
+ LABEL_COMPRESSION_TYPE,
+ methodname);
+ } else {
+ rv = -1;
+ }
+ }
+ return rv;
+}
+
+/**
+ * Given an array of <b>n</b> compressed_result_t in <b>results</b>,
+ * as produced by compress_multiple, store them all into the
+ * consdiffmgr, and store handles to them in the <b>handles_out</b>
+ * array.
+ *
+ * Return CDM_DIFF_PRESENT if any was stored, and CDM_DIFF_ERROR if none
+ * was stored.
+ */
+static cdm_diff_status_t
+store_multiple(consensus_cache_entry_handle_t **handles_out,
+ int n,
+ const compress_method_t *methods,
+ const compressed_result_t *results,
+ const char *description)
+{
+ cdm_diff_status_t status = CDM_DIFF_ERROR;
+ consdiffmgr_ensure_space_for_files(n);
+
+ int i;
+ for (i = 0; i < n; ++i) {
+ compress_method_t method = methods[i];
+ uint8_t *body_out = results[i].body;
+ size_t bodylen_out = results[i].bodylen;
+ config_line_t *labels = results[i].labels;
+ const char *methodname = compression_method_get_name(method);
+ if (body_out && bodylen_out && labels) {
+ /* Success! Store the results */
+ log_info(LD_DIRSERV, "Adding %s, compressed with %s",
+ description, methodname);
+
+ consensus_cache_entry_t *ent =
+ consensus_cache_add(cdm_cache_get(),
+ labels,
+ body_out,
+ bodylen_out);
+
+ status = CDM_DIFF_PRESENT;
+ handles_out[i] = consensus_cache_entry_handle_new(ent);
+ consensus_cache_entry_decref(ent);
+ }
+ }
+ return status;
+}
+
+/**
* An object passed to a worker thread that will try to produce a consensus
* diff.
*/
@@ -1235,24 +1320,10 @@ consensus_diff_worker_threadfn(void *state_, void *work_)
job->out[0].body,
job->out[0].bodylen);
- unsigned u;
- for (u = 1; u < n_diff_compression_methods(); ++u) {
- compress_method_t method = compress_diffs_with[u];
- const char *methodname = compression_method_get_name(method);
- char *result;
- size_t sz;
- if (0 == tor_compress(&result, &sz, consensus_diff, difflen, method)) {
- job->out[u].body = (uint8_t*)result;
- job->out[u].bodylen = sz;
- job->out[u].labels = config_lines_dup(common_labels);
- cdm_labels_prepend_sha3(&job->out[u].labels, LABEL_SHA3_DIGEST,
- job->out[u].body,
- job->out[u].bodylen);
- config_line_prepend(&job->out[u].labels,
- LABEL_COMPRESSION_TYPE,
- methodname);
- }
- }
+ compress_multiple(job->out+1,
+ n_diff_compression_methods()-1,
+ compress_diffs_with+1,
+ (const uint8_t*)consensus_diff, difflen, common_labels);
config_free_lines(common_labels);
return WQ_RPL_REPLY;
@@ -1318,36 +1389,20 @@ consensus_diff_worker_replyfn(void *work_)
cache = 0;
}
- int status = CDM_DIFF_ERROR;
consensus_cache_entry_handle_t *handles[ARRAY_LENGTH(compress_diffs_with)];
memset(handles, 0, sizeof(handles));
- consdiffmgr_ensure_space_for_files(n_diff_compression_methods());
+ char description[128];
+ tor_snprintf(description, sizeof(description),
+ "consensus diff from %s to %s",
+ lv_from_digest, lv_to_digest);
- unsigned u;
- for (u = 0; u < n_diff_compression_methods(); ++u) {
- compress_method_t method = compress_diffs_with[u];
- uint8_t *body_out = job->out[u].body;
- size_t bodylen_out = job->out[u].bodylen;
- config_line_t *labels = job->out[u].labels;
- const char *methodname = compression_method_get_name(method);
- if (body_out && bodylen_out && labels) {
- /* Success! Store the results */
- log_info(LD_DIRSERV, "Adding consensus diff from %s to %s, "
- "compressed with %s",
- lv_from_digest, lv_to_digest, methodname);
+ int status = store_multiple(handles,
+ n_diff_compression_methods(),
+ compress_diffs_with,
+ job->out,
+ description);
- consensus_cache_entry_t *ent =
- consensus_cache_add(cdm_cache_get(),
- labels,
- body_out,
- bodylen_out);
-
- status = CDM_DIFF_PRESENT;
- handles[u] = consensus_cache_entry_handle_new(ent);
- consensus_cache_entry_decref(ent);
- }
- }
if (status != CDM_DIFF_PRESENT) {
/* Failure! Nothing to do but complain */
log_warn(LD_DIRSERV,
@@ -1357,6 +1412,7 @@ consensus_diff_worker_replyfn(void *work_)
status = CDM_DIFF_ERROR;
}
+ unsigned u;
for (u = 0; u < ARRAY_LENGTH(handles); ++u) {
compress_method_t method = compress_diffs_with[u];
if (cache) {