Give the user some control over progressbar invasiveness

Progress reporting is useful but also has its drawbacks, like writing
to the calling terminal when it's not in the appropriate state, or
slowing down the process being reported on. This commit addresses both
situations:

1. a set of 3 configuration variables is introduced with which the user
can control (via macports.conf) after how long the progressbar should
appear, if it should also show indeterminate progress (aka "we're busy")
and what operations should report progress in addition to the traditional
ones (fetch, build, destroot). The defaults for these are the current
hardwired settings. The "also_for" setting is designed to be a list that
currently only accepts "de/activation" for the recent progress reporting
added to `port activate` and `port deactivate`. (Which causes a significant
increase in duration of those operations.)

2. a Pextlib function is introduced to determine whether `port` runs as a
foreground process connected to a terminal. This function is called to
check the current state before doing any actual progressbar output. It
thus becomes possible to push a long-running operation (say, a build) to
the background and do other work in the same terminal, without getting
frequent terminal and most likely illegible output.

doc/macports.conf.in

@@ -136,6 +136,20 @@ variants_conf       	@MPCONFIGDIR_EXPANDED@/variants.conf
 # Keep logs after successful installations.
 #keeplogs            	no
 
+# Progress reporting.
+# MacPorts will show a progressbar during lengthy operations which take more
+# than $progressbar_after milliseconds. The bar reports determinate progress
+# when the total amount of work and the work done are quantified. It can also
+# show an "indeterminate" indication of work being done (and switch to this
+# display after a certain amount of time) if $progressbar_type is set to `both`.
+# The operations that use this feature are downloads, builds and rev-upgrade,
+# plus a list of additional operations $progressbar_also_for which can include
+# `de/activation` (for `port deactivate` and `port activate`) and possibly more
+# in the future. NB: no quotes for the string values!
+# progressbar_after     500
+# progressbar_type      both
+# progressbar_also_for  de/activation
+
 # URLs that MacPorts attempts to download to find out whether a new version was
 # released. Multiple values, space-separated; only one of the URLs needs to be
 # available. Downloads will be attempted in the specified order.

src/macports1.0/macports.tcl

@@ -52,6 +52,7 @@ namespace eval macports {
     foreach opt [list binpath auto_path extra_env portdbformat \
         portarchivetype portimage_mode hfscompression portautoclean \
         porttrace portverbose keeplogs destroot_umask release_urls release_version_urls \
+        progressbar_after progressbar_type progressbar_also_for \
         rsync_server rsync_options rsync_dir \
         startupitem_autostart startupitem_type startupitem_install \
         place_worksymlink xcodeversion xcodebuildcmd xcodecltversion xcode_license_unaccepted \
@@ -78,6 +79,7 @@ namespace eval macports {
         registry.path registry.format user_home user_path user_ssh_auth_sock \
         portarchivetype portarchive_hfscompression archivefetch_pubkeys \
         portautoclean portimage_mode porttrace keeplogs portverbose destroot_umask \
+        progressbar_after progressbar_type progressbar_also_for \
         rsync_server rsync_options rsync_dir startupitem_autostart startupitem_type startupitem_install \
         place_worksymlink macportsuser sudo_user \
         configureccache ccache_dir ccache_size configuredistcc configurepipe buildnicevalue buildmakejobs \
@@ -983,6 +985,9 @@ proc mportinit {{up_ui_options {}} {up_options {}} {up_variations {}}} {
         macports::cxx_stdlib \
         macports::hfscompression \
         macports::portarchive_hfscompression \
+        macports::progressbar_after \
+        macports::progressbar_type \
+        macports::progressbar_also_for \
         macports::host_cache \
         macports::porturl_prefix_map \
         macports::ui_options \
@@ -1460,6 +1465,16 @@ Please edit sources.conf and change '$url' to '[string range $url 0 26]macports/
     }
     set portarchive_hfscompression $hfscompression
 
+    if {![info exists progressbar_after]} {
+        set progressbar_after 500
+    }
+    if {![info exists progressbar_type]} {
+        set progressbar_type "both"
+    }
+    if {![info exists progressbar_also_for]} {
+        set progressbar_also_for "de/activation"
+    }
+
     # Set rync options
     if {![info exists rsync_server]} {
         set rsync_server rsync.macports.org

src/pextlib1.0/Pextlib.c

@@ -1150,6 +1150,40 @@ int ClonefileCmd(ClientData clientData UNUSED, Tcl_Interp *interp, int objc, Tcl
     return TCL_ERROR;
 }
 
+/*
+	processIsForeground
+	
+	synopsis: processIsForeground
+
+	Returns true if the process is running in the foreground or false
+	if in the background.
+*/
+int IsProcessForegroundCmd(ClientData clientData UNUSED, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[])
+{
+	/* Check the arg count */
+	if (objc != 1) {
+        Tcl_WrongNumArgs(interp, 1, objv, NULL);
+		return TCL_ERROR;
+	}
+
+	int fd, fdo = fileno(stdout);
+    if ((fd = isatty(fdo) ? fdo : open("/dev/tty", O_RDONLY)) != -1) {
+        const pid_t pgrp = getpgrp();
+        const pid_t tcpgrp = tcgetpgrp(fd);
+        if (fd != fdo) {
+            close(fd);
+        }
+        if (pgrp != -1 && tcpgrp != -1) {
+            Tcl_SetObjResult(interp, Tcl_NewBooleanObj(pgrp == tcpgrp));
+            return TCL_OK;
+        }
+    }
+    Tcl_SetErrno(errno);
+    Tcl_ResetResult(interp);
+    Tcl_AppendResult(interp, "processIsForeground: ", (char *)Tcl_PosixError(interp), NULL);
+	return TCL_ERROR;
+}
+
 int Pextlib_Init(Tcl_Interp *interp)
 {
     if (Tcl_InitStubs(interp, "8.4", 0) == NULL)
@@ -1214,6 +1248,8 @@ int Pextlib_Init(Tcl_Interp *interp)
     Tcl_CreateObjCommand(interp, "fs_clone_capable", FSCloneCapableCmd, NULL, NULL);
     Tcl_CreateObjCommand(interp, "clonefile", ClonefileCmd, NULL, NULL);
 
+    Tcl_CreateObjCommand(interp, "processIsForeground", IsProcessForegroundCmd, NULL, NULL);
+
     if (Tcl_PkgProvide(interp, "Pextlib", "1.0") != TCL_OK)
         return TCL_ERROR;
 

src/port/port.tcl

@@ -4829,9 +4829,11 @@ namespace eval portclient::progress {
     proc initDelay {} {
         variable show
         variable startTime
+        variable showTimeThreshold
 
         set startTime [clock milliseconds]
         set show no
+        set showTimeThreshold ${macports::progressbar_after}
     }
 
     ##
@@ -4907,7 +4909,9 @@ namespace eval portclient::progress {
             }
             update {
                 lassign $args now total
-                if {[showProgress $now $total] eq "yes"} {
+                # Check on each update if we're still outputting to a tty - the user can
+                # have pushed us into the background.
+                if {[processIsForeground] && ([showProgress $now $total] eq "yes")} {
                     set barPrefix "      "
                     set barPrefixLen [string length $barPrefix]
                     if {$total != 0} {
@@ -4919,11 +4923,13 @@ namespace eval portclient::progress {
             }
             intermission -
             finish {
-                # erase to start of line
-                ::term::ansi::send::esolch stderr
-                # return cursor to start of line
-                puts -nonewline stderr "\r"
-                flush stderr
+                if {[processIsForeground]} {
+                    # erase to start of line
+                    ::term::ansi::send::esolch stderr
+                    # return cursor to start of line
+                    puts -nonewline stderr "\r"
+                    flush stderr
+                }
             }
         }
 
@@ -4955,7 +4961,9 @@ namespace eval portclient::progress {
             }
             update {
                 lassign $args type total now speed
-                if {[showProgress $now $total] eq "yes"} {
+                # Check on each update if we're still outputting to a tty - the user can
+                # have pushed us into the background.
+                if {[processIsForeground] && ([showProgress $now $total] eq "yes")} {
                     set barPrefix "      "
                     set barPrefixLen [string length $barPrefix]
                     if {$total != 0} {
@@ -4974,11 +4982,13 @@ namespace eval portclient::progress {
                 }
             }
             finish {
-                # erase to start of line
-                ::term::ansi::send::esolch stderr
-                # return cursor to start of line
-                puts -nonewline stderr "\r"
-                flush stderr
+                if {[processIsForeground]} {
+                    # erase to start of line
+                    ::term::ansi::send::esolch stderr
+                    # return cursor to start of line
+                    puts -nonewline stderr "\r"
+                    flush stderr
+                }
             }
         }
 

src/port1.0/portprogress.tcl

@@ -41,6 +41,7 @@ namespace eval portprogress {
     variable indeterminate_timer        0
 
     # If our progress callback should issue indeterminate progress updates
+    variable allow_indeterminate        yes
     variable indeterminate              yes
 
     # ninja ([<completed tasks>/<pending tasks>])
@@ -53,7 +54,8 @@ namespace eval portprogress {
 # A SystemCmd callback that parses common target progress formats to display
 # a progress bar
 proc portprogress::target_progress_callback {event} {
-    global portverbose
+    global portverbose progressbar_type
+    variable allow_indeterminate
     variable indeterminate
     variable indeterminate_timer
     variable indeterminate_threshold
@@ -66,7 +68,11 @@ proc portprogress::target_progress_callback {event} {
 
     switch -- [dict get $event type] {
         exec {
-            set indeterminate yes
+            # reset allow_indeterminate to the user/default-configured setting
+            if {${progressbar_type} ne "both"} {
+			  set allow_indeterminate no
+		  }
+            set indeterminate ${allow_indeterminate}
             set indeterminate_timer 0
             ui_progress_generic start
         }
@@ -102,7 +108,7 @@ proc portprogress::target_progress_callback {event} {
                 set time_diff [expr { $time_now - $time_last }]
 
                 if {${time_diff} >= ${indeterminate_threshold}} {
-                    set indeterminate yes
+                    set indeterminate ${allow_indeterminate}
                 }
             }
 

src/registry2.0/portimage.tcl

@@ -63,6 +63,7 @@ namespace eval portimage {
 variable force 0
 variable noexec 0
 variable UI_PREFIX {---> }
+variable show_progressbar 1
 
 # takes a composite version spec rather than separate version,revision,variants
 proc activate_composite {name {v ""} {optionslist ""}} {
@@ -161,6 +162,7 @@ proc deactivate_composite {name {v ""} {optionslist ""}} {
 
 proc deactivate {name {version ""} {revision ""} {variants 0} {options ""}} {
     variable UI_PREFIX
+    variable show_progressbar
 
     if {[dict exists $options ports_force] && [string is true -strict [dict get $options ports_force]] } {
         # this not using the namespace variable is correct, since activate
@@ -247,6 +249,12 @@ proc deactivate {name {version ""} {revision ""} {variants 0} {options ""}} {
         }
     }
 
+    if {[lsearch -exact ${macports::progressbar_also_for} "de/activation"] < 0} {
+        set show_progressbar 0
+        # minimise the overhead of calling _progress: it wouldn't do a thing so make it a stub
+        proc _progress {args} {}
+    }
+
     ui_msg "$UI_PREFIX [format [msgcat::mc "Deactivating %s @%s"] $name $specifier]"
 
     try {
@@ -428,6 +436,8 @@ proc _activate_directories {dirs imageroot} {
 # extract an archive to a directory
 # returns: path to the extracted directory
 proc extract_archive_to_imagedir {location} {
+    variable show_progressbar
+
     set extractdir [file rootname $location]
     if {[file exists $extractdir]} {
         set extractdir [mkdtemp ${extractdir}XXXXXXXX]
@@ -586,7 +596,11 @@ proc extract_archive_to_imagedir {location} {
         } else {
             set cmdstring "${unarchive.pipe_cmd} ( ${unarchive.cmd} ${unarchive.pre_args} ${unarchive.args} )"
         }
-        system -callback portimage::_extract_progress $cmdstring
+        if {${show_progressbar}} {
+            system -callback portimage::_extract_progress $cmdstring
+        } else {
+            system $cmdstring
+        }
     } on error {_ eOptions} {
         ::file delete -force $extractdir
         throw [dict get $eOptions -errorcode] [dict get $eOptions -errorinfo]
@@ -627,7 +641,9 @@ proc _extract_progress {event} {
 }
 
 proc _progress {args} {
-    if {[macports::ui_isset ports_verbose]} {
+    variable show_progressbar
+
+    if {!${show_progressbar} || [macports::ui_isset ports_verbose]} {
         return
     }
 
@@ -693,6 +709,7 @@ proc _activate_contents {port {rename_list {}}} {
     variable keep_imagedir
     variable progress_step
     variable progress_total_steps
+    variable show_progressbar
 
     set files [list]
     set baksuffix .mp_[clock seconds]
@@ -701,6 +718,12 @@ proc _activate_contents {port {rename_list {}}} {
     set imagefiles [$port imagefiles]
     set num_imagefiles [llength $imagefiles]
 
+    if {[lsearch -exact ${macports::progressbar_also_for} "de/activation"] < 0} {
+        set show_progressbar 0
+        # minimise the overhead of calling _progress: it wouldn't do a thing so make it a stub
+        proc _progress {args} {}
+    }
+
     set progress_step 0
     if {[::file isfile $location]} {
         set progress_total_steps [expr {$num_imagefiles * 3}]