Implement multibar UI

Multiplexed download requires ability to draw UI for multiple active progress
bars. To implement it we use ANSI codes to move cursor up/down and then
redraw the required progress bar.
`pacman_multibar_ui.active_downloads` field represents the list of active
downloads that correspond to progress bars.
`struct pacman_progress_bar` is a data structure for a progress bar.

In some cases (e.g. database downloads) we want to keep progress bars in order.
In some other cases (package downloads) we want to move completed items to the
top of the screen. Function `multibar_move_completed_up` allows to configure
such behavior.

Per discussion in the maillist we do not want to show download progress for
signature files.

Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Allan McRae <allan@archlinux.org>

3 files changed, 34 insertions, 30 deletions

diff --git a/lib/libalpm/be_sync.c b/lib/libalpm/be_sync.c
index add1a576..86015ab6 100644
--- a/lib/libalpm/be_sync.c
+++ b/lib/libalpm/be_sync.c
@@ -366,6 +366,7 @@ int SYMEXPORT alpm_dbs_update(alpm_handle_t *handle, alpm_list_t *dbs, int force
 		if(siglevel & ALPM_SIG_DATABASE) {
 			struct dload_payload *sig_payload;
 			CALLOC(sig_payload, 1, sizeof(*sig_payload), GOTO_ERR(handle, ALPM_ERR_MEMORY, cleanup));
+			sig_payload->signature = 1;
 
 			/* print filename into a buffer (leave space for separator and .sig) */
 			len = strlen(db->treename) + strlen(dbext) + 5;
diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c
index 2f360ab8..9ab0e5c4 100644
--- a/lib/libalpm/dload.c
+++ b/lib/libalpm/dload.c
@@ -90,6 +90,11 @@ static int dload_progress_cb(void *file, curl_off_t dltotal, curl_off_t dlnow,
 	off_t current_size, total_size;
 	alpm_download_event_progress_t cb_data = {0};
 
+	/* do not print signature files progress bar */
+	if(payload->signature) {
+		return 0;
+	}
+
 	/* avoid displaying progress bar for redirects with a body */
 	if(payload->respcode >= 300) {
 		return 0;
@@ -100,6 +105,11 @@ static int dload_progress_cb(void *file, curl_off_t dltotal, curl_off_t dlnow,
 		return 1;
 	}
 
+	if(dlnow < 0 || dltotal <= 0 || dlnow > dltotal) {
+		/* bogus values : stop here */
+		return 0;
+	}
+
 	current_size = payload->initial_size + dlnow;
 
 	/* is our filesize still under any set limit? */
@@ -115,34 +125,15 @@ static int dload_progress_cb(void *file, curl_off_t dltotal, curl_off_t dlnow,
 
 	total_size = payload->initial_size + dltotal;
 
-	if(dltotal == 0 || payload->prevprogress == total_size) {
+	if(payload->prevprogress == total_size) {
 		return 0;
 	}
 
-	/* initialize the progress bar here to avoid displaying it when
-	 * a repo is up to date and nothing gets downloaded.
-	 * payload->handle->dlcb will receive the remote_name
-	 * and the following arguments:
-	 * 0, -1: download initialized
-	 * 0, 0: non-download event
-	 * x {x>0}, x: download complete
-	 * x {x>0, x<y}, y {y > 0}: download progress, expected total is known */
-	if(!payload->cb_initialized) {
-		cb_data.downloaded = 0;
-		cb_data.total = -1;
-		payload->cb_initialized = 1;
-	}
-	if(payload->prevprogress == current_size) {
-		cb_data.downloaded = 0;
-		cb_data.total = 0;
-	} else {
 	/* do NOT include initial_size since it wasn't part of the package's
 	 * download_size (nor included in the total download size callback) */
-		cb_data.downloaded = dlnow;
-		cb_data.total = dltotal;
-	}
+	cb_data.total = dltotal;
+	cb_data.downloaded = dlnow;
 	payload->handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_PROGRESS, &cb_data);
-
 	payload->prevprogress = current_size;
 
 	return 0;
@@ -375,6 +366,8 @@ static int curl_download_internal(struct dload_payload *payload,
 	double remote_size, bytes_dl;
 	struct sigaction orig_sig_pipe, orig_sig_int;
 	CURLcode curlerr;
+	alpm_download_event_init_t init_cb_data = {0};
+	alpm_download_event_completed_t completed_cb_data = {0};
 	/* shortcut to our handle within the payload */
 	alpm_handle_t *handle = payload->handle;
 	CURL *curl = curl_easy_init();
@@ -444,6 +437,8 @@ static int curl_download_internal(struct dload_payload *payload,
 	dload_interrupted = 0;
 	mask_signal(SIGINT, &inthandler, &orig_sig_int);
 
+	handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_INIT, &init_cb_data);
+
 	/* perform transfer */
 	curlerr = curl_easy_perform(curl);
 	_alpm_log(handle, ALPM_LOG_DEBUG, "curl returned error %d from transfer\n",
@@ -604,6 +599,10 @@ cleanup:
 		raise(SIGINT);
 	}
 
+	completed_cb_data.total = bytes_dl;
+	completed_cb_data.result = ret;
+	handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_COMPLETED, &completed_cb_data);
+
 	return ret;
 }
 
@@ -665,7 +664,6 @@ static int curl_multi_check_finished_download(CURLM *curlm, CURLMsg *msg,
 	long remote_time = -1;
 	struct stat st;
 	char hostname[HOSTNAME_SIZE];
-	alpm_download_event_completed_t cb_data = {0};
 	int ret = -1;
 
 	curlerr = curl_easy_getinfo(curl, CURLINFO_PRIVATE, &payload);
@@ -825,9 +823,12 @@ cleanup:
 		unlink(payload->tempfile_name);
 	}
 
-	cb_data.total = bytes_dl;
-	cb_data.result = ret;
-	handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_COMPLETED, &cb_data);
+	if(!payload->signature) {
+		alpm_download_event_completed_t cb_data = {0};
+		cb_data.total = bytes_dl;
+		cb_data.result = ret;
+		handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_COMPLETED, &cb_data);
+	}
 
 	curl_multi_remove_handle(curlm, curl);
 	curl_easy_cleanup(curl);
@@ -945,9 +946,11 @@ static int curl_multi_download_internal(alpm_handle_t *handle,
 			struct dload_payload *payload = payloads->data;
 
 			if(curl_multi_add_payload(handle, curlm, payload, localpath) == 0) {
-				alpm_download_event_init_t cb_data = {.optional = payload->errors_ok};
+				if(!payload->signature) {
+					alpm_download_event_init_t cb_data = {.optional = payload->errors_ok};
+					handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_INIT, &cb_data);
+				}
 
-				handle->dlcb(payload->remote_name, ALPM_DOWNLOAD_INIT, &cb_data);
 				payloads = payloads->next;
 				// TODO: report that download has started
 			} else {
@@ -1129,6 +1132,7 @@ char SYMEXPORT *alpm_fetch_pkgurl(alpm_handle_t *handle, const char *url)
 
 		sig_filepath = filecache_find_url(handle, payload.fileurl);
 		if(sig_filepath == NULL) {
+			payload.signature = 1;
 			payload.handle = handle;
 			payload.trust_remote_name = 1;
 			payload.force = 1;
@@ -1184,5 +1188,4 @@ void _alpm_dload_payload_reset_for_retry(struct dload_payload *payload)
 	payload->initial_size += payload->prevprogress;
 	payload->prevprogress = 0;
 	payload->unlink_on_fail = 0;
-	payload->cb_initialized = 0;
 }
diff --git a/lib/libalpm/dload.h b/lib/libalpm/dload.h
index a40b51b7..1e4af755 100644
--- a/lib/libalpm/dload.h
+++ b/lib/libalpm/dload.h
@@ -42,7 +42,7 @@ struct dload_payload {
 	int errors_ok;
 	int unlink_on_fail;
 	int trust_remote_name;
-	int cb_initialized;
+	int signature; /* specifies if the payload is a signature file */
 #ifdef HAVE_LIBCURL
 	CURL *curl;
 	char error_buffer[CURL_ERROR_SIZE];