X-Git-Url: https://ruderich.org/simon/gitweb/?p=config%2Fdotfiles.git;a=blobdiff_plain;f=lib.sh;h=206f9954a3841041da04e8b4417dccf497b889dc;hp=e222da42f00a52c7b391cecd01322b564dad6e0b;hb=9571f95bc667454fab054ba67477d90ff323d87c;hpb=fbc6b0059f5345e8974bd713dc041a4e39e18c73

diff --git a/lib.sh b/lib.sh
index e222da4..206f995 100644
--- a/lib.sh
+++ b/lib.sh
@@ -4,14 +4,41 @@
 
 
 # csh gives the error "Unknown colorls variable `su'." when used with newer
-# options supported by zsh or GNU ls.
+# options supported by Zsh or GNU ls.
 unset LS_COLORS
 
-# Get path to m4 because it's later redefined as function.
-m4=`which m4`
 
+# Check if the given program is installed. Returns 0 if it exists, 1
+# otherwise; so it can be used in if.
+installed() {
+    [ x`which $1 2>&1 | cut -c 1` = x/ ] || return 1
+}
+
+# Print the current OS. The following OS are supported at the moment:
+# - Debian (debian)
+# - Gentoo (gentoo)
+# - Mac OS X (darwin)
+# - Solaris/OpenSolaris (sun)
+# - FreeBSD (freebsd)
+# If an unsupported OS is used an error is printed.
+os() {
+    if [ -f /etc/debian_version ]; then
+        echo debian
+    elif [ -f /etc/gentoo-release ]; then
+        echo gentoo
+    elif [ x`uname` = xDarwin ]; then
+        echo darwin
+    elif [ x`uname` = xSunOS ]; then
+        echo sun
+    elif [ x`uname` = xFreeBSD ]; then
+        echo freebsd
+    else
+        echo unsupported OS! >&2
+        return 1
+    fi
+}
 
-# Creates a symbolic link for file $1 in dirname of $2 with name of basenmae
+# Creates a symbolic link for file $1 in dirname of $2 with name of basename
 # $2.
 #
 # `./link.sh example ~/.examplerc` creates a symbolic link to example
@@ -19,8 +46,9 @@ m4=`which m4`
 link() {
     # Get all necessary paths.
     pwd=`pwd`
-    base=`dirname "$2"`
-    source=`echo -n "$pwd/$1" | sed "s|$base/||"`
+    base=`echo "$2" | sed "s|\~|$HOME|"` # expand ~, some sh don't do it
+    base=`dirname "$base"`
+    source=`echo "$pwd/$1" | sed "s|$base/||"`
     target=`basename "$2"`
 
     # Go to the directory where the link is going to be created.
@@ -28,13 +56,14 @@ link() {
 
     # Abort if the target file exists and is no symbolic link. Prevents
     # overwriting real files.
-    if [ -e "$target" -a ! -h "$target" ]; then
+    if [ \( -f "$target" -a ! -h "$target" \) -o \
+         \( -s "$target" -a ! -h "$target" \) ]; then
         echo "link(): target '$target' exists already and is no symbolic link!" >&2
         exit 1
     fi
 
-    # Make sure the source exists.
-    if [ ! -e "$source" ]; then
+    # Make sure the source exists (is file, directory or link).
+    if [ ! -f "$source" -a ! -d "$source" -a ! -h "$source" ]; then
         echo "link(): source '$source' doesn't exist!" >&2
         exit 1
     fi
@@ -50,24 +79,67 @@ link() {
     unset pwd base source target
 }
 
-# m4 wrapper which uses $1.m4 as template file, feeds it to m4 and writes it
-# to $1 with a warning at the beginning to not edit the generated file.
+# Write a warning to $1 to make clear it should not be modified. $2 is the
+# source for the generated file. Also print a message to stdout that the file
+# $1 was generated from $2 using the command $3 with options $4.
+warning() {
+    echo "###################################" > $1
+    echo "# WARNING! DO NOT EDIT THIS FILE! #" >> $1
+    echo "###################################" >> $1
+    echo >> $1
+    echo "# It was generated from $2 on `date`." >> $1
+    echo >> $1
+
+    # Display given options if there were any (Zsh has a problem with $options
+    # as variable name).
+    option=
+    if [ -n "$4" ]; then
+        option=" with options '$4'"
+    fi
+    # Write message to stdout.
+    echo "$3: generating '$1' from '$2'$option"
+
+    unset option
+}
+
+# Generate a file using several methods. A warning not to edit it is
+# automatically added to the created file and a message printed to stdout
+# through warning().
+#
+# The following commands are possible; the file extension for the source file
+# in brackets.
 #
-# All arguments (except the first which is the filename) are passed to m4.
-m4() {
-    # First argument is file name.
-    file=$1
+# - m4   (.m4): pipe $2.m4 through m4 then write it to $2
+# - awk  (.in): pipe $2.in through awk then write it to $2
+# - perl (.in): pipe $2.in through perl then write it to $2
+# - cat  ($3):  copy $2$3 to $2
+generate() {
+    # Get command and target file.
+    command="$1"
+    file="$2"
+    # Remove arguments from list.
     shift
+    shift
+
+    # Set extension for the used commands. When cat is used $3 is used as
+    # extension.
+    if [ x"$command" = xm4 ]; then
+        extension=.m4
+    elif [ x"$command" = xawk -o x"$command" = xperl ]; then
+        extension=.in
+    elif [ x"$command" = xcat ]; then
+        extension="$1" # is $3 in reality, $1 because of shifting
+        shift
+    # Print a warning and exit if an unsupported command is used.
+    else
+        echo "generate(): command '$command' not supported!" >&2
+        exit 1
+    fi
+
+    # Add warning to file and write a message to stdout.
+    warning "$file" "$file$extension" $command "$*"
+    # Generate $file from $file$extension using the given command.
+    cat "$file$extension" | $command "$@" >> "$file"
 
-    # Write a warning to the generated file.
-    echo "###################################" > $file
-    echo "# WARNING! DO NOT EDIT THIS FILE! #" >> $file
-    echo "###################################" >> $file
-    echo >> $file
-    echo "# It was generated from $file.m4 on `date`." >> $file
-    echo >> $file
-
-    # Process $1.m4 with m4 using the given options.
-    echo "m4(): generating '$file' from '$file.m4' with options '$*'"
-    $m4 $* $file.m4 >> $file
+    unset command file
 }