[pacman-dev] [PATCH] Implement multibar UI

Anatol Pomozov anatol.pomozov at gmail.com
Fri Apr 17 18:59:06 UTC 2020


Hi

On Fri, Apr 17, 2020 at 11:55 AM Anatol Pomozov
<anatol.pomozov at gmail.com> wrote:
>
> Multiplexed download requires ability to draw UI for multiple active progress bars.
> To implement it we use ANSI codes to move cursor up/down.
> `active_dls` variable represents the list of active downloads.
> `struct dl_progress_bar` is a data structure for an active progress bar.
>
> In some cases we want to keep progress bars in order (e.g. db downloads).
> In some other cases (package downloads) we want to move completed items to the
> top of the screen.  Global `multibar_move_complete_top` allows to configure
> such behavior.
>
> Optional downloads (such as optional signature files) do not have a
> visible progress bar.
>
> Signed-off-by: Anatol Pomozov <anatol.pomozov at gmail.com>
> ---
>  lib/libalpm/dload.c   |  31 +---
>  lib/libalpm/dload.h   |   1 -
>  src/pacman/callback.c | 401 +++++++++++++++++++++++++++++-------------
>  src/pacman/callback.h |   3 +
>  src/pacman/sync.c     |   2 +
>  5 files changed, 294 insertions(+), 144 deletions(-)
>
> diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c
> index c09abde4..cf467ff0 100644
> --- a/lib/libalpm/dload.c
> +++ b/lib/libalpm/dload.c
> @@ -100,6 +100,11 @@ 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 +120,15 @@ 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;
> @@ -1160,5 +1146,4 @@ 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..142568e8 100644
> --- a/lib/libalpm/dload.h
> +++ b/lib/libalpm/dload.h
> @@ -42,7 +42,6 @@ struct dload_payload {
>         int errors_ok;
>         int unlink_on_fail;
>         int trust_remote_name;
> -       int cb_initialized;
>  #ifdef HAVE_LIBCURL
>         CURL *curl;
>         char error_buffer[CURL_ERROR_SIZE];
> diff --git a/src/pacman/callback.c b/src/pacman/callback.c
> index 387319b6..a4aafada 100644
> --- a/src/pacman/callback.c
> +++ b/src/pacman/callback.c
> @@ -18,6 +18,8 @@
>   *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
>   */
>
> +#include <assert.h>
> +#include <stdbool.h>
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <string.h>
> @@ -45,6 +47,8 @@ static off_t list_total = 0.0;
>  static int on_progress = 0;
>  static alpm_list_t *output = NULL;
>
> +static void cursor_goto_end(void);
> +
>  /* update speed for the fill_progress based functions */
>  #define UPDATE_SPEED_MS 200
>
> @@ -152,11 +156,7 @@ static void fill_progress(const int bar_percent, const int disp_percent,
>                 printf(" %3d%%", disp_percent);
>         }
>
> -       if(bar_percent == 100) {
> -               putchar('\n');
> -       } else {
> -               putchar('\r');
> -       }
> +       putchar('\r');
>         fflush(stdout);
>  }
>
> @@ -346,6 +346,7 @@ void cb_event(alpm_event_t *event)
>                 case ALPM_EVENT_DB_RETRIEVE_FAILED:
>                 case ALPM_EVENT_RETRIEVE_DONE:
>                 case ALPM_EVENT_RETRIEVE_FAILED:
> +                       cursor_goto_end();
>                         flush_output_list();
>                         on_progress = 0;
>                         break;
> @@ -629,6 +630,7 @@ void cb_progress(alpm_progress_t event, const char *pkgname, int percent,
>         fill_progress(percent, percent, cols - infolen);
>
>         if(percent == 100) {
> +               putchar('\n');
>                 flush_output_list();
>                 on_progress = 0;
>         } else {
> @@ -647,124 +649,121 @@ void cb_dl_total(off_t total)
>         }
>  }
>
> -/* callback to handle display of download progress */
> -static void dload_progress_event(const char *filename, off_t file_xfered, off_t file_total)
> +static int dload_progressbar_enabled(void)
>  {
> -       static double rate_last;
> -       static off_t xfered_last;
> -       static int64_t initial_time = 0;
> -       int infolen;
> -       int filenamelen;
> -       char *fname, *p;
> -       /* used for wide character width determination and printing */
> -       int len, wclen, wcwid, padwid;
> -       wchar_t *wcfname;
> +       return !config->noprogressbar && getcols() != 0;
> +}
>
> -       int totaldownload = 0;
> -       off_t xfered, total;
> -       double rate = 0.0;
> -       unsigned int eta_h = 0, eta_m = 0, eta_s = 0;
> -       double rate_human, xfered_human;
> -       const char *rate_label, *xfered_label;
> -       int file_percent = 0, total_percent = 0;
> +struct dl_progress_bar {
> +       const char *filename;
> +       off_t xfered;
> +       off_t total_size;
> +       uint64_t init_time; /* Time when this download started doing any progress */
> +       uint64_t sync_time; /* Last time we updated the bar info */
> +       double rate;
> +       unsigned int eta; /* ETA in seconds */
> +       bool completed; /* transfer is completed */
> +       bool visible; /* whether to show the bar, some downloads (e.g. db.sig files) are not shown */
> +};
>
> -       const unsigned short cols = getcols();
> +/* List of active downloads handled by multibar UI.
> + * Once the first download in the list is completed it is removed
> + * from this list and we never redraw it anymore.
> + * If the download in this list then UI can redraw the progress bar or change
> + * the order of the bars (e.g. completed bar is moved to the top of the list)
> + */
> +alpm_list_t *active_dls = NULL;
> +/* Number of active progress bars that multibar UI handles.
> + * Each progress bar has a corresponding active download.
> + * Note that some downloads might not have a bar, e.g. optional signature files
> + * do not have a corresponding bar.
> + */
> +size_t active_bars_no = 0;
>
> -       /* Nothing has changed since last callback; stop here */
> -       if(file_xfered == 0 && file_total == 0) {
> -               return;
> -       }
> +int multibar_move_complete_top = 0;
>
> -       if(config->noprogressbar || cols == 0) {
> -               if(file_xfered == 0 && file_total == -1) {
> -                       printf(_("downloading %s...\n"), filename);
> -                       fflush(stdout);
> -               }
> -               return;
> -       }
> +/* Cursor position relative to the first active progress bar,
> + * e.g. 0 means the first active progress bar, active_bars_no-1 means the last bar,
> + * active_bars_no - is the line below all progress bars.
> + */
> +int cursor_lineno = 0;
>
> -       infolen = cols * 6 / 10;
> -       if(infolen < 50) {
> -               infolen = 50;
> -       }
> -       /* only use TotalDownload if enabled and we have a callback value */
> -       if(config->totaldownload && list_total) {
> -               /* sanity check */
> -               if(list_xfered + file_total <= list_total) {
> -                       totaldownload = 1;
> -               } else {
> -                       /* bogus values : don't enable totaldownload and reset */
> -                       list_xfered = 0;
> -                       list_total = 0;
> -               }
> +/* Move console cursor `lines` up */
> +static void cursor_line_up(unsigned int lines)
> +{
> +       assert(lines > 0);
> +       printf("\x1B[%dF", lines);
> +}
> +
> +/* Move console cursor `lines` down */
> +static void cursor_line_down(unsigned int lines)
> +{
> +       assert(lines > 0);
> +       printf("\x1B[%dE", lines);
> +}
> +
> +/* Erase line from the cursor position till the end of the line */
> +static void console_erase_line(void)
> +{
> +       printf("\x1B[K");
> +}
> +
> +/* Goto the line that corresponds to num-th active download */
> +static void cursor_goto_bar(int num)
> +{
> +       if(num > cursor_lineno) {
> +               cursor_line_down(num - cursor_lineno);
> +       } else if(num < cursor_lineno) {
> +               cursor_line_up(cursor_lineno - num);
>         }
> +       cursor_lineno = num;
> +}
>
> -       if(totaldownload) {
> -               xfered = list_xfered + file_xfered;
> -               total = list_total;
> -       } else {
> -               xfered = file_xfered;
> -               total = file_total;
> -       }
> -
> -       /* this is basically a switch on xfered: 0, total, and
> -        * anything else */
> -       if(file_xfered == 0 && file_total == -1) {
> -               /* set default starting values, ensure we only call this once
> -                * if TotalDownload is enabled */
> -               if(!totaldownload || (totaldownload && list_xfered == 0)) {
> -                       initial_time = get_time_ms();
> -                       xfered_last = (off_t)0;
> -                       rate_last = 0.0;
> -                       get_update_timediff(1);
> -               }
> -       } else if(xfered > total || xfered < 0) {
> -               /* bogus values : stop here */
> -               return;
> -       } else if(file_xfered == file_total) {
> -               /* compute final values */
> -               int64_t timediff = get_time_ms() - initial_time;
> -               if(timediff > 0) {
> -                       rate = (double)xfered / (timediff / 1000.0);
> -                       /* round elapsed time (in ms) to the nearest second */
> -                       eta_s = (unsigned int)(timediff + 500) / 1000;
> -               } else {
> -                       eta_s = 0;
> -               }
> -       } else {
> -               /* compute current average values */
> -               int64_t timediff = get_update_timediff(0);
> +/* Goto the line *after* the last active progress bar */
> +static void cursor_goto_end(void)
> +{
> +       cursor_goto_bar(active_bars_no);
> +}
>
> -               if(timediff < UPDATE_SPEED_MS) {
> -                       /* return if the calling interval was too short */
> -                       return;
> +/* Returns true if element with the specified name is found, false otherwise */
> +static bool find_bar_for_filename(const char *filename, int *index, struct dl_progress_bar **bar)
> +{
> +       int i = 0;
> +       alpm_list_t *listitem = active_dls;
> +       for(; listitem; listitem = listitem->next) {
> +               struct dl_progress_bar *b = listitem->data;
> +               if (b->filename == filename /* or strcmp() ? */) {
> +                       *index = i;
> +                       *bar = b;
> +                       return true;
>                 }
> -               rate = (double)(xfered - xfered_last) / (timediff / 1000.0);
> -               /* average rate to reduce jumpiness */
> -               rate = (rate + 2 * rate_last) / 3;
> -               if(rate > 0.0) {
> -                       eta_s = (total - xfered) / rate;
> -               } else {
> -                       eta_s = UINT_MAX;
> +               if(b->visible) {
> +                       i++;
>                 }
> -               rate_last = rate;
> -               xfered_last = xfered;
>         }
>
> -       if(file_total) {
> -               file_percent = (file_xfered * 100) / file_total;
> -       } else {
> -               file_percent = 100;
> -       }
> +       return false;
> +}
> +
> +static void draw_dl_progress_bar(struct dl_progress_bar *bar)
> +{
> +       int infolen;
> +       int filenamelen;
> +       char *fname, *p;
> +       /* used for wide character width determination and printing */
> +       int len, wclen, wcwid, padwid;
> +       wchar_t *wcfname;
> +       unsigned int eta_h = 0, eta_m = 0, eta_s = bar->eta;
> +       double rate_human, xfered_human;
> +       const char *rate_label, *xfered_label;
> +       int file_percent = 0;
>
> -       if(totaldownload) {
> -               total_percent = ((list_xfered + file_xfered) * 100) /
> -                       list_total;
> +       const unsigned short cols = getcols();
>
> -               /* if we are at the end, add the completed file to list_xfered */
> -               if(file_xfered == file_total) {
> -                       list_xfered += file_total;
> -               }
> +       if(bar->total_size) {
> +               file_percent = (bar->xfered * 100) / bar->total_size;
> +       } else {
> +               file_percent = 100;
>         }
>
>         /* fix up time for display */
> @@ -773,13 +772,13 @@ static void dload_progress_event(const char *filename, off_t file_xfered, off_t
>         eta_m = eta_s / 60;
>         eta_s -= eta_m * 60;
>
> -       len = strlen(filename);
> +       len = strlen(bar->filename);
>         fname = malloc(len + 1);
> -       memcpy(fname, filename, len + 1);
> +       memcpy(fname, bar->filename, len + 1);
>         /* strip package or DB extension for cleaner look */
>         if((p = strstr(fname, ".pkg")) || (p = strstr(fname, ".db")) || (p = strstr(fname, ".files"))) {
>                 /* tack on a .sig suffix for signatures */
> -               if(memcmp(&filename[len - 4], ".sig", 4) == 0) {
> +               if(memcmp(&bar->filename[len - 4], ".sig", 4) == 0) {
>                         memcpy(p, ".sig", 4);
>
>                         /* adjust length for later calculations */
> @@ -790,6 +789,11 @@ static void dload_progress_event(const char *filename, off_t file_xfered, off_t
>                 fname[len] = '\0';
>         }
>
> +       infolen = cols * 6 / 10;
> +       if(infolen < 50) {
> +               infolen = 50;
> +       }
> +
>         /* 1 space + filenamelen + 1 space + 6 for size + 1 space + 3 for label +
>          * + 2 spaces + 4 for rate + 1 space + 3 for label + 2 for /s + 1 space +
>          * 8 for eta, gives us the magic 33 */
> @@ -824,8 +828,8 @@ static void dload_progress_event(const char *filename, off_t file_xfered, off_t
>
>         }
>
> -       rate_human = humanize_size((off_t)rate, '\0', -1, &rate_label);
> -       xfered_human = humanize_size(xfered, '\0', -1, &xfered_label);
> +       rate_human = humanize_size((off_t)bar->rate, '\0', -1, &rate_label);
> +       xfered_human = humanize_size(bar->xfered, '\0', -1, &xfered_label);
>
>         printf(" %ls%-*s ", wcfname, padwid, "");
>         /* We will show 1.62 MiB/s, 11.6 MiB/s, but 116 KiB/s and 1116 KiB/s */
> @@ -850,19 +854,176 @@ static void dload_progress_event(const char *filename, off_t file_xfered, off_t
>         free(fname);
>         free(wcfname);
>
> -       if(totaldownload) {
> -               fill_progress(file_percent, total_percent, cols - infolen);
> +       fill_progress(file_percent, file_percent, cols - infolen);
> +       return;
> +}
> +
> +static void dload_init_event(const char *filename, alpm_download_event_init_t *data)
> +{
> +       (void)data;
> +
> +       if(!dload_progressbar_enabled()) {
> +               printf(_(" %s downloading...\n"), filename);
> +               return;
> +       }
> +
> +       struct dl_progress_bar *bar = calloc(1, sizeof(struct dl_progress_bar));
> +       if(!bar) {
> +               return;
> +       }
> +       bar->filename = filename;
> +       bar->init_time = get_time_ms();
> +       bar->rate = 0.0;
> +       bar->visible = !data->optional;
> +       active_dls = alpm_list_add(active_dls, bar);
> +
> +       if(bar->visible) {
> +               cursor_goto_end();
> +               printf(_(" %s downloading...\n"), filename);
> +               cursor_lineno++;
> +               active_bars_no++;
> +       }
> +}
> +
> +/* render download progress */
> +static void dload_progress_event(const char *filename, alpm_download_event_progress_t *data)
> +{
> +       int index;
> +       struct dl_progress_bar *bar;
> +       int64_t curr_time = get_time_ms();
> +       double last_chunk_rate;
> +       int64_t timediff;
> +
> +       if(!dload_progressbar_enabled()) {
> +               return;
> +       }
> +
> +       assert(find_bar_for_filename(filename, &index, &bar));
> +
> +       /* compute current average values */
> +       timediff = curr_time - bar->sync_time;
> +
> +       if(timediff < UPDATE_SPEED_MS) {
> +               /* return if the calling interval was too short */
> +               return;
> +       }
> +       bar->sync_time = curr_time;
> +
> +       last_chunk_rate = (double)(data->downloaded - bar->xfered) / (timediff / 1000.0);
> +       /* average rate to reduce jumpiness */
> +       bar->rate = (last_chunk_rate + 2 * bar->rate) / 3;
> +       if(bar->rate > 0.0) {
> +               bar->eta = (data->total - data->downloaded) / bar->rate;
>         } else {
> -               fill_progress(file_percent, file_percent, cols - infolen);
> +               bar->eta = UINT_MAX;
> +       }
> +
> +       /* Total size is received after the download starts. */
> +       bar->total_size = data->total;
> +       bar->xfered = data->downloaded;
> +
> +       if(bar->visible) {
> +               cursor_goto_bar(index);
> +               draw_dl_progress_bar(bar);
> +               fflush(stdout);
>         }
> -       return;
>  }
>
> +/* download completed */
> +static void dload_complete_event(const char *filename, alpm_download_event_completed_t *data)
> +{
> +       int index;
> +       struct dl_progress_bar *bar;
> +       int64_t timediff;
> +
> +       if(!dload_progressbar_enabled()) {
> +               return;
> +       }
> +
> +       assert(find_bar_for_filename(filename, &index, &bar));
> +       bar->completed = true;
> +
> +       /* This may not have been initialized if the download finished before
> +        * an alpm_download_event_progress_t event happened */
> +       bar->total_size = data->total;
> +
> +       if(bar->visible) {
> +               if(data->result == 1) {
> +                       cursor_goto_bar(index);
> +                       printf(_(" %s is up to date"), bar->filename);
> +                       /* The line contains text from previous status. Erase these leftovers. */
> +                       console_erase_line();
> +               } else if(data->result == 0) {
> +                       /* compute final values */
> +                       bar->xfered = bar->total_size;
> +                       timediff = get_time_ms() - bar->init_time;
> +
> +                       /* if transfer was too fast, treat it as a 1ms transfer, for the sake
> +                        * of the rate calculation */
> +                       if(timediff < 1)
> +                               timediff = 1;
> +
> +                       bar->rate = (double)bar->xfered / (timediff / 1000.0);
> +                       /* round elapsed time (in ms) to the nearest second */
> +                       bar->eta = (unsigned int)(timediff + 500) / 1000;
> +
> +                       if(multibar_move_complete_top && index != 0) {
> +                               /* If this item completed then move it to the top.
> +                                * Swap 0-th bar data with `index`-th one
> +                                */
> +                               struct dl_progress_bar *former_topbar = active_dls->data;
> +                               alpm_list_t *baritem = alpm_list_nth(active_dls, index);
> +                               active_dls->data = bar;
> +                               baritem->data = former_topbar;
> +
> +                               cursor_goto_bar(index);
> +                               draw_dl_progress_bar(former_topbar);
> +
> +                               index = 0;
> +                       }
> +
> +                       cursor_goto_bar(index);
> +                       draw_dl_progress_bar(bar);
> +               } else {
> +                       cursor_goto_bar(index);
> +                       printf(_(" %s failed to download"), bar->filename);
> +                       console_erase_line();
> +               }
> +               fflush(stdout);
> +       }
> +
> +       /* If the first bar is completed then there is no reason to keep it
> +        * in the list as we are not going to redraw it anymore.
> +        */
> +       while(active_dls) {
> +               alpm_list_t *head = active_dls;
> +               struct dl_progress_bar *j = head->data;
> +               if(j->completed) {
> +                       if(j->visible) {
> +                               cursor_lineno--;
> +                               active_bars_no--;
> +                       }
> +                       active_dls = alpm_list_remove_item(active_dls, head);
> +                       free(head);
> +                       free(j);
> +               } else {
> +                       break;
> +               }
> +       }
> +}
> +
> +/* callback to handle display of download progress */
>  void cb_download(const char *filename, alpm_download_event_type_t event, void *data)
>  {
> -       if(event == ALPM_DOWNLOAD_PROGRESS) {
> -               alpm_download_event_progress_t *progress = data;
> -               dload_progress_event(filename, progress->downloaded, progress->total);
> +       if(event == ALPM_DOWNLOAD_INIT) {
> +               dload_init_event(filename, data);
> +       } else if(event == ALPM_DOWNLOAD_PROGRESS) {
> +               dload_progress_event(filename, data);
> +       } else if(event == ALPM_DOWNLOAD_COMPLETED) {
> +               dload_complete_event(filename, data);
> +       } else {
> +               pm_printf(ALPM_LOG_ERROR, _("unknown callback event type %d for %s\n"),
> +                               event, filename);
>         }
>  }
>
> diff --git a/src/pacman/callback.h b/src/pacman/callback.h
> index 6d92e86b..916b9dad 100644
> --- a/src/pacman/callback.h
> +++ b/src/pacman/callback.h
> @@ -44,4 +44,7 @@ void cb_download(const char *filename, alpm_download_event_type_t event,
>  __attribute__((format(printf, 2, 0)))
>  void cb_log(alpm_loglevel_t level, const char *fmt, va_list args);
>
> +/* specify if multibar should move complete bars to the top of the screen */
> +int multibar_move_complete_top;
> +
>  #endif /* PM_CALLBACK_H */
> diff --git a/src/pacman/sync.c b/src/pacman/sync.c
> index f7dcb958..d5886f13 100644
> --- a/src/pacman/sync.c
> +++ b/src/pacman/sync.c
> @@ -35,6 +35,7 @@
>  #include "pacman.h"
>  #include "util.h"
>  #include "package.h"
> +#include "callback.h"
>  #include "conf.h"
>
>  static int unlink_verbose(const char *pathname, int ignore_missing)
> @@ -824,6 +825,7 @@ int sync_prepare_execute(void)
>                 goto cleanup;
>         }
>
> +       multibar_move_complete_top = 1;
>         if(alpm_trans_commit(config->handle, &data) == -1) {
>                 alpm_errno_t err = alpm_errno(config->handle);
>                 pm_printf(ALPM_LOG_ERROR, _("failed to commit transaction (%s)\n"),
> --


Alright, it is the last big commit for parallel-downloads feature. The
rest of the changes in my WIP queue are straightforward cleanups.


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