casync-http: Move chunks download in a separate function for clarity

The goal is to make the run() function more readable, and only outline
the major steps, while the bulk of the work is left to other functions.

Signed-off-by: Arnaud Rebillout <[email protected]>

Author: elboulangero

src/casync-http.c

@@ -481,14 +481,92 @@ static int acquire_file(CaRemote *rr, CURL *handle) {
         return 1;
 }
 
+static int acquire_chunks(CaRemote *rr, const char *store_url) {
+        _cleanup_free_ char *url_buffer = NULL;
+        _cleanup_(curl_easy_cleanupp) CURL *curl = NULL;
+        _cleanup_(realloc_buffer_free) ReallocBuffer chunk_buffer = {};
+        int r;
+
+        r = make_curl_easy_handle(&curl, write_chunk, &chunk_buffer, NULL);
+        if (r < 0)
+                return r;
+
+        for (;;) {
+                CURLcode c;
+                CaChunkID id;
+                long protocol_status;
+
+                if (quit) {
+                        log_info("Got exit signal, quitting.");
+                        return 0;
+                }
+
+                r = process_remote(rr, PROCESS_UNTIL_HAVE_REQUEST);
+                if (r == -EPIPE)
+                        return 0;
+                if (r < 0)
+                        return r;
+
+                r = ca_remote_next_request(rr, &id);
+                if (r == -ENODATA)
+                        continue;
+                if (r < 0)
+                        return log_error_errno(r, "Failed to determine next chunk to get: %m");
+
+                free(url_buffer);
+                url_buffer = chunk_url(store_url, &id);
+                if (!url_buffer)
+                        return log_oom();
+
+                r = configure_curl_easy_handle(curl, url_buffer);
+                if (r < 0)
+                        return r;
+
+                log_debug("Acquiring %s...", url_buffer);
+
+                c = robust_curl_easy_perform(curl);
+                if (c != CURLE_OK)
+                        return log_error_curle(c, "Failed to acquire %s", url_buffer);
+
+                c = curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &protocol_status);
+                if (c != CURLE_OK)
+                        return log_error_curle(c, "Failed to query response code");
+
+                r = process_remote(rr, PROCESS_UNTIL_CAN_PUT_CHUNK);
+                if (r == -EPIPE)
+                        return 0;
+                if (r < 0)
+                        return r;
+
+                if (protocol_status_ok(arg_protocol, protocol_status)) {
+                        r = ca_remote_put_chunk(rr, &id, CA_CHUNK_COMPRESSED, realloc_buffer_data(&chunk_buffer), realloc_buffer_size(&chunk_buffer));
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to write chunk: %m");
+                } else {
+                        if (arg_verbose)
+                                log_error("%s server failure %ld while requesting %s",
+                                          protocol_str(arg_protocol), protocol_status,
+                                          url_buffer);
+
+                        r = ca_remote_put_missing(rr, &id);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to write missing message: %m");
+                }
+
+                realloc_buffer_empty(&chunk_buffer);
+
+                r = process_remote(rr, PROCESS_UNTIL_WRITTEN);
+                if (r == -EPIPE)
+                        return 0;
+                if (r < 0)
+                        return r;
+        }
+}
+
 static int run(int argc, char *argv[]) {
         const char *base_url, *archive_url, *index_url, *wstore_url;
         size_t n_stores = 0, current_store = 0;
-        _cleanup_(curl_easy_cleanupp) CURL *curl = NULL;
         _cleanup_(ca_remote_unrefp) CaRemote *rr = NULL;
-        _cleanup_(realloc_buffer_free) ReallocBuffer chunk_buffer = {};
-        _cleanup_free_ char *url_buffer = NULL;
-        long protocol_status;
         int r;
 
         if (argc < _CA_REMOTE_ARG_MAX) {
@@ -574,86 +652,18 @@ static int run(int argc, char *argv[]) {
                         return r;
         }
 
-        for (;;) {
+        if (n_stores > 0) {
                 const char *store_url;
-                CaChunkID id;
-
-                if (quit) {
-                        log_info("Got exit signal, quitting.");
-                        return 0;
-                }
-
-                if (n_stores == 0)  /* No stores? Then we did all we could do */
-                        break;
-
-                if (!curl) {
-                        r = make_curl_easy_handle(&curl, write_chunk, &chunk_buffer, NULL);
-                        if (r < 0)
-                                return r;
-                }
-
-                r = process_remote(rr, PROCESS_UNTIL_HAVE_REQUEST);
-                if (r == -EPIPE)
-                        return 0;
-                if (r < 0)
-                        return r;
-
-                r = ca_remote_next_request(rr, &id);
-                if (r == -ENODATA)
-                        continue;
-                if (r < 0)
-                        return log_error_errno(r, "Failed to determine next chunk to get: %m");
 
                 current_store = current_store % n_stores;
                 if (wstore_url)
-                        store_url = current_store == 0 ? wstore_url : argv[current_store + _CA_REMOTE_ARG_MAX - 1];
+                        store_url = current_store == 0 ? wstore_url :
+                                argv[current_store + _CA_REMOTE_ARG_MAX - 1];
                 else
                         store_url = argv[current_store + _CA_REMOTE_ARG_MAX];
                 /* current_store++; */
 
-                free(url_buffer);
-                url_buffer = chunk_url(store_url, &id);
-                if (!url_buffer)
-                        return log_oom();
-
-                r = configure_curl_easy_handle(curl, url_buffer);
-                if (r < 0)
-                        return r;
-
-                log_debug("Acquiring %s...", url_buffer);
-
-                if (robust_curl_easy_perform(curl) != CURLE_OK)
-                        return log_error_errno(-EIO, "Failed to acquire %s", url_buffer);
-
-                if (curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &protocol_status) != CURLE_OK)
-                        return log_error_errno(-EIO, "Failed to query response code");
-
-                r = process_remote(rr, PROCESS_UNTIL_CAN_PUT_CHUNK);
-                if (r == -EPIPE)
-                        return 0;
-                if (r < 0)
-                        return r;
-
-                if (protocol_status_ok(arg_protocol, protocol_status)) {
-                        r = ca_remote_put_chunk(rr, &id, CA_CHUNK_COMPRESSED, realloc_buffer_data(&chunk_buffer), realloc_buffer_size(&chunk_buffer));
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to write chunk: %m");
-                } else {
-                        if (arg_verbose)
-                                log_error("%s server failure %ld while requesting %s",
-                                          protocol_str(arg_protocol), protocol_status,
-                                          url_buffer);
-
-                        r = ca_remote_put_missing(rr, &id);
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to write missing message: %m");
-                }
-
-                realloc_buffer_empty(&chunk_buffer);
-
-                r = process_remote(rr, PROCESS_UNTIL_WRITTEN);
-                if (r == -EPIPE)
-                        return 0;
+                r = acquire_chunks(rr, store_url);
                 if (r < 0)
                         return r;
         }