Merge branch 'master' into openbsd

6 files changed, 195 insertions, 109 deletions

diff --git a/README.markdown b/README.markdown
index 3e566177..66864981 100644
--- a/README.markdown
+++ b/README.markdown
@@ -443,6 +443,7 @@ Installed by the `install-bin` target:
 *   `maybe(1df)` is like `true(1)` or `false(1)`; given a probability of
     success,
     it exits with success or failure. Good for quick tests.
+*   `mex(1df)` makes given filenames in `$PATH` executable.
 *   `mftl(1df)` finds usable-looking targets in Makefiles.
 *   `mkcp(1df)` creates a directory and copies preceding arguments into it.
 *   `mkmv(1df)` creates a directory and moves preceding arguments into it.
diff --git a/bash/bash_completion.d/mex.bash b/bash/bash_completion.d/mex.bash
new file mode 100644
index 00000000..d25f1824
--- /dev/null
+++ b/bash/bash_completion.d/mex.bash
@@ -0,0 +1,15 @@
+# Completion setup for mex(1df), completing non-executable files in $PATH
+_mex() {
+    local -a path
+    IFS=: read -ra path < <(printf '%s\n' "$PATH")
+    local dir name
+    for dir in "${path[@]}" ; do
+        [[ -d $dir ]] || continue
+        for name in "$dir"/* ; do
+            [[ -f $name ]] || continue
+            ! [[ -x $name ]] || continue
+            COMPREPLY[${#COMPREPLY[@]}]=${name##*/}
+        done
+    done
+}
+complete -F _mex mex
diff --git a/bash/bashrc b/bash/bashrc
index 1c7d7802..088182ef 100644
--- a/bash/bashrc
+++ b/bash/bashrc
@@ -14,7 +14,7 @@ esac
 # shellcheck disable=SC2128
 [ -n "$BASH_VERSINFO" ] || return
 ((BASH_VERSINFO[0] == 2)) &&
-    ((10#${BASH_VERSINFO[1]%%[![:digit:]]*} < 5)) &&
+    ((10#${BASH_VERSINFO[1]%%[!0-9]*} < 5)) &&
     return
 
 # Don't do anything if running a restricted shell
@@ -32,9 +32,6 @@ HISTTIMEFORMAT='%F %T  '
 # Use a more compact format for the time builtin's output
 TIMEFORMAT='real:%lR user:%lU sys:%lS'
 
-# Don't allow the creation of aliases, functions are better
-enable -n alias unalias
-
 # Autocorrect fudged paths in cd calls
 shopt -s cdspell
 # Update the hash table properly
@@ -45,8 +42,6 @@ shopt -s checkwinsize
 shopt -s cmdhist
 # Include dotfiles in pattern matching
 shopt -s dotglob
-# Don't use aliases, functions are better
-shopt -u expand_aliases
 # Enable advanced pattern matching
 shopt -s extglob
 # Append rather than overwrite Bash history
diff --git a/bash/bashrc.d/prompt.bash b/bash/bashrc.d/prompt.bash
index e7e285a7..856e20e6 100644
--- a/bash/bashrc.d/prompt.bash
+++ b/bash/bashrc.d/prompt.bash
@@ -31,46 +31,43 @@ prompt() {
             # Add terminating "$" or "#" sign
             PS1=$PS1'\$'
 
-            # Count available colors
-            local -i colors
-            colors=$( {
-                tput colors || tput Co
-            } 2>/dev/null )
-
-            # Prepare reset code
-            local reset
-            reset=$( {
-                tput sgr0 || tput me
-            } 2>/dev/null )
-
-            # Decide prompt color formatting based on color availability
-            local format
-
-            # Check if we have non-bold bright green available
-            if ((colors >= 16)) ; then
-                format=$( {
-                    : "${PROMPT_COLOR:=10}"
-                    tput setaf "$PROMPT_COLOR" ||
-                    tput setaf "$PROMPT_COLOR" 0 0 ||
-                    tput AF "$PROMPT_COLOR" ||
-                    tput AF "$PROMPT_COLOR" 0 0
-                } 2>/dev/null )
-
-            # If we have only eight colors, use bold green
-            elif ((colors >= 8)) ; then
-                format=$( {
-                    : "${PROMPT_COLOR:=2}"
-                    tput setaf "$PROMPT_COLOR" ||
-                    tput AF "$PROMPT_COLOR"
-                    tput bold || tput md
-                } 2>/dev/null )
-
-            # Otherwise, we just try bold
-            else
-                format=$( {
-                    tput bold || tput md
-                } 2>/dev/null )
-            fi
+            # Declare variables to contain terminal control strings
+            local format reset
+
+            # Disregard output and error from these tput(1) calls
+            {
+                # Count available colors
+                local -i colors
+                colors=$(tput colors || tput Co)
+
+                # Prepare reset code
+                reset=$(tput sgr0 || tput me)
+
+                # Check if we have non-bold bright green available
+                if ((colors >= 16)) ; then
+                    format=$(
+                        : "${PROMPT_COLOR:=10}"
+                        tput setaf "$PROMPT_COLOR" ||
+                        tput setaf "$PROMPT_COLOR" 0 0 ||
+                        tput AF "$PROMPT_COLOR" ||
+                        tput AF "$PROMPT_COLOR" 0 0
+                    )
+
+                # If we have only eight colors, use bold green
+                elif ((colors >= 8)) ; then
+                    format=$(
+                        : "${PROMPT_COLOR:=2}"
+                        tput setaf "$PROMPT_COLOR" ||
+                        tput AF "$PROMPT_COLOR"
+                        tput bold || tput md
+                    )
+
+                # Otherwise, we just try bold
+                else
+                    format=$(tput bold || tput md)
+                fi
+
+            } >/dev/null 2>&1
 
             # String it all together
             PS1='\['"$format"'\]'"$PS1"'\['"$reset"'\] '
@@ -90,74 +87,77 @@ prompt() {
 
         # Git prompt function
         git)
-            # Bail if we're not in a work tree--or, implicitly, if we don't
-            # have git(1).
-            local iswt
-            iswt=$(git rev-parse --is-inside-work-tree 2>/dev/null)
-            [[ $iswt = true ]] || return
-
-            # Refresh index so e.g. git-diff-files(1) is accurate
-            git update-index --refresh >/dev/null 2>&1
-
-            # Find a local branch, remote branch, or tag (annotated or not), or
-            # failing all of that just show the short commit ID, in that order
-            # of preference; if none of that works, bail out
-            local name
-            name=$( {
-                git symbolic-ref --quiet HEAD ||
-                git describe --tags --exact-match HEAD ||
-                git rev-parse --short HEAD
-            } 2>/dev/null) || return
-            name=${name##*/}
-            [[ -n $name ]] || return
-
-            # Check various files in .git to flag processes
-            local proc
-            [[ -d .git/rebase-merge || -d .git/rebase-apply ]] &&
-                proc=${proc:+$proc,}'REBASE'
-            [[ -f .git/MERGE_HEAD ]] &&
-                proc=${proc:+$proc,}'MERGE'
-            [[ -f .git/CHERRY_PICK_HEAD ]] &&
-                proc=${proc:+$proc,}'PICK'
-            [[ -f .git/REVERT_HEAD ]] &&
-                proc=${proc:+$proc,}'REVERT'
-            [[ -f .git/BISECT_LOG ]] &&
-                proc=${proc:+$proc,}'BISECT'
-
-            # Collect symbols representing repository state
-            local state
-
-            # Upstream HEAD has commits after local HEAD; we're "behind"
-            local -i behind
-            behind=$(git rev-list --count 'HEAD..@{u}' 2>/dev/null)
-            ((behind)) && state=${state}'<'
-
-            # Local HEAD has commits after upstream HEAD; we're "ahead"
-            local -i ahead
-            ahead=$(git rev-list --count '@{u}..HEAD' 2>/dev/null)
-            ((ahead)) && state=${state}'>'
-
-            # Tracked files are modified
-            git diff-files --no-ext-diff --quiet ||
-                state=${state}'!'
-
-            # Changes are staged
-            git diff-index --cached --no-ext-diff --quiet HEAD 2>/dev/null ||
-                state=${state}'+'
-
-            # There are some untracked and unignored files
-            git ls-files --directory --error-unmatch --exclude-standard \
-                --no-empty-directory --others -- ':/*' >/dev/null 2>&1 &&
-                state=${state}'?'
 
-            # There are stashed changes
-            git rev-parse --quiet --verify refs/stash >/dev/null &&
-                state=${state}'^'
+            # Wrap as compound command; we don't want to see output from any of
+            # these git(1) calls
+            {
+                # Bail if we're not in a work tree--or, implicitly, if we don't
+                # have git(1).
+                [[ -n $(git rev-parse --is-inside-work-tree) ]] ||
+                    return
+
+                # Refresh index so e.g. git-diff-files(1) is accurate
+                git update-index --refresh
+
+                # Find a local branch, remote branch, or tag (annotated or
+                # not), or failing all of that just show the short commit ID,
+                # in that order of preference; if none of that works, bail out
+                local name
+                name=$(
+                    git symbolic-ref --quiet HEAD ||
+                    git describe --tags --exact-match HEAD ||
+                    git rev-parse --short HEAD
+                ) || return
+                name=${name##*/}
+                [[ -n $name ]] || return
+
+                # Check various files in .git to flag processes
+                local proc
+                [[ -d .git/rebase-merge || -d .git/rebase-apply ]] &&
+                    proc=${proc:+"$proc",}'REBASE'
+                [[ -f .git/MERGE_HEAD ]] &&
+                    proc=${proc:+"$proc",}'MERGE'
+                [[ -f .git/CHERRY_PICK_HEAD ]] &&
+                    proc=${proc:+"$proc",}'PICK'
+                [[ -f .git/REVERT_HEAD ]] &&
+                    proc=${proc:+"$proc",}'REVERT'
+                [[ -f .git/BISECT_LOG ]] &&
+                    proc=${proc:+"$proc",}'BISECT'
+
+                # Collect symbols representing repository state
+                local state
+
+                # Upstream HEAD has commits after local HEAD; we're "behind"
+                (($(git rev-list --count 'HEAD..@{u}'))) &&
+                    state=${state}'<'
+
+                # Local HEAD has commits after upstream HEAD; we're "ahead"
+                (($(git rev-list --count '@{u}..HEAD'))) &&
+                    state=${state}'>'
+
+                # Tracked files are modified
+                git diff-files --no-ext-diff --quiet ||
+                    state=${state}'!'
+
+                # Changes are staged
+                git diff-index --cached --no-ext-diff --quiet HEAD ||
+                    state=${state}'+'
+
+                # There are some untracked and unignored files
+                git ls-files --directory --error-unmatch --exclude-standard \
+                    --no-empty-directory --others -- ':/*' &&
+                    state=${state}'?'
+
+                # There are stashed changes
+                git rev-parse --quiet --verify refs/stash &&
+                    state=${state}'^'
+
+            } >/dev/null 2>&1
 
             # Print the status in brackets; add a git: prefix only if there
             # might be another VCS prompt (because PROMPT_VCS is set)
             printf '(%s%s%s%s)' \
-                "${PROMPT_VCS:+git:}" "$name" "${proc:+:$proc}" "$state"
+                "${PROMPT_VCS:+git:}" "$name" "${proc:+:"$proc"}" "$state"
             ;;
 
         # Subversion prompt function
diff --git a/bin/mex b/bin/mex
new file mode 100755
index 00000000..005149d8
--- /dev/null
+++ b/bin/mex
@@ -0,0 +1,53 @@
+#!/bin/sh
+# Make the first non-executable instance of files with the given names in $PATH
+# executable
+self=mex
+
+# Check we have at least one argument
+if [ "$#" -eq 0 ] ; then
+    printf >&2 '%s: At least one name required\n' "$self"
+    exit 2
+fi
+
+# Iterate through the given names
+for name ; do
+
+    # Clear the found variable
+    found=
+
+    # Start iterating through $PATH, with colon prefix/suffix to correctly
+    # handle the fenceposts
+    path=:$PATH:
+    while [ -n "$path" ] ; do
+
+        # Pop the first directory off $path into $dir
+        dir=${path%%:*}
+        path=${path#*:}
+
+        # Check $dir is non-null
+        [ -n "$dir" ] || continue
+
+        # If a file with the needed name exists in the directory and isn't
+        # executable, we've found our candidate and can stop iterating
+        if [ -f "$dir"/"$name" ] && ! [ -x "$dir"/"$name" ] ; then
+            found=$dir/$name
+            break
+        fi
+    done
+
+    # If the "found" variable was defined to something, we'll try to change its
+    # permissions
+    if [ -n "$found" ] ; then
+        chmod +x -- "$found" || ex=1
+
+    # If not, we'll report that we couldn't find it, and flag an error for the
+    # exit status
+    else
+        printf >&2 '%s: No non-executable name "%s" in PATH\n' "$self" "$name"
+        ex=1
+    fi
+done
+
+# We exit 1 if any of the names weren't found or if changing their permissions
+# failed
+exit "${ex:-0}"
diff --git a/man/man1/mex.1df b/man/man1/mex.1df
new file mode 100644
index 00000000..0fa584da
--- /dev/null
+++ b/man/man1/mex.1df
@@ -0,0 +1,22 @@
+.TH MEX 1df "September 2016" "Manual page for mex"
+.SH NAME
+.B mex
+\- make first instance of filenames in $PATH executable
+.SH USAGE
+.B mex
+name
+.br
+.B mex
+name1 name2 name3
+.br
+PATH=/foo:/bar/baz
+name
+.SH DESCRIPTION
+Iterate through the contents of the PATH variable looking for files with any of
+the specified names that do not have the executable permissions bit set, and
+try to set it if found. Exit nonzero if any of the names were not found, or if
+any of the permissions changes failed.
+.SH SEE ALSO
+chmod(1), eds(1df)
+.SH AUTHOR
+Tom Ryder <tom@sanctum.geek.nz>