Merge pull request #122 from kerl/git_build1.0

Support release and tarball retrieval from github

2 files changed, 271 insertions, 137 deletions

diff --git a/README.md b/README.md
index 352495f..02a809e 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ Kerl aims to be shell agnostic and its only dependencies, excluding what's requi
 All is done so that, once a specific release has been built, creating a new installation is as fast as possible.
 
 Downloading
-===========
+-----------
 
 You can download the script directly from github:
 
@@ -26,13 +26,18 @@ Optionally download and install kerl's zsh-completion file from https://github.c
 
 
 How it works
-============
+------------
 
-Kerl keeps tracks of the releases it downloaded, built and installed,
-allowing easy installations to new destinations (without complete rebuilding) and easy switches between Erlang/OTP installations.
+Kerl keeps tracks of the releases it downloads, builds and installs, allowing
+easy installations to new destinations (without complete rebuilding) and easy
+switches between Erlang/OTP installations.
+
+By default, kerl downloads source tarballs from the [official Erlang website](http://www.erlang.org), but
+you can tell kerl to download tarballs of Erlang source code from the tags
+pushed to the [official source code](https://github.com/erlang/otp) by setting `KERL_BUILD_BACKEND=git`
 
 Usage
-=====
+-----
 
 List the available releases (kerl ignores releases < 10):
 
@@ -90,7 +95,9 @@ And at last activate it:
 
     $ . /path/to/install/dir/activate
 
-Activation will backup your $PATH, prepend it with the installation's bin/ directory. Thus it's only valid for the current shell session, and until you activate another installation or call `kerl_deactivate`.
+Activation will backup your $PATH, prepend it with the installation's bin/
+directory. Thus it's only valid for the current shell session, and until you
+activate another installation or call `kerl_deactivate`.
 
 You're now ready to work with your r14b02 installation:
 
@@ -136,7 +143,12 @@ You can easily deploy an installation to another host having `ssh` and `rsync` a
     Later on, you can leave the installation typing:
     kerl_deactivate
 
-As an experimental feature, you can build Erlang directly from a git repository with a command of the form `kerl build git <git_url> <git_version> <build_name>` where <git_version> can be either a branch, a tag or a commit id as it will be passed to `git checkout`:
+Building from a git source
+--------------------------
+
+You can build Erlang directly from a git repository with a command of the form
+`kerl build git <git_url> <git_version> <build_name>` where `<git_version>` can
+be either a branch, a tag or a commit id that will be passed to `git checkout`:
 
     $ kerl build git https://github.com/erlang/otp.git dev r14b02_dev
     Checking Erlang/OTP git repositoy from https://github.com/erlang/otp.git...
@@ -144,12 +156,13 @@ As an experimental feature, you can build Erlang directly from a git repository
     Erlang/OTP r14b02_dev from git has been successfully built
 
 Tuning
-======
+------
 
 You can tune kerl using the .kerlrc file in your $HOME directory.
 
 You can set the following variables:
 
+- `KERL_BUILD_BACKEND` which source code download provider to use - (`tarball` - default) erlang.org or github (`git`)
 - `KERL_DOWNLOAD_DIR` where to put downloaded files, defaults to $HOME/.kerl/archives
 - `KERL_BUILD_DIR` where to hold the builds, defaults to $HOME/.kerl/builds
 - `KERL_DEFAULT_INSTALL_DIR` if set in ~/.kerlrc, install builds to this dir if no path is provided on installs, (recommend `$KERL_BASE_DIR/installs`)
@@ -157,20 +170,34 @@ You can set the following variables:
 - `KERL_CONFIGURE_APPLICATIONS` if non-empty, subset of applications used in the builds (and subsequent installations) process, e.g. `kernel stdlib sasl`
 - `KERL_CONFIGURE_DISABLE_APPLICATIONS` if non-empty, subset of applications disabled in the builds (and subsequent installations) process, e.g. `odbc`
 - `KERL_SASL_STARTUP` use SASL system startup instead of minimal
-- `KERL_USE_AUTOCONF` use autoconf in the builds process
-- `KERL_INSTALL_MANPAGES` if non-empty will install manpages
-- `KERL_INSTALL_HTMLDOCS` if non-empty will install HTML docs
 - `KERL_DEPLOY_SSH_OPTIONS` if additional options are required, e.g. `-qx -o PasswordAuthentication=no`
 - `KERL_DEPLOY_RSYNC_OPTIONS` if additional options are required, e.g. `--delete`
 - `KERL_ENABLE_PROMPT` if set, the prompt will be prefixed with the name of the active build 
+- `KERL_BUILD_DOCS` if set, will build documentation from source code repository
+- `KERL_USE_AUTOCONF` use autoconf in the builds process (**note**: implied by the `git` build backend)
+
+### Options for tarball builds only ###
+
+These options only work when `KERL_BUILD_BACKEND=tarball` (the default) **and**
+if `KERL_BUILD_DOCS` is not set. That is, they are *strictly* for backward
+compatibility. They will probably be removed in a future release.
+
+- `KERL_INSTALL_MANPAGES` if non-empty will install manpages into `/install/path/man`
+- `KERL_INSTALL_HTMLDOCS` if non-empty will install HTML docs into `/install/path/html`
+
+If you want documentation for git based builds, set `KERL_BUILD_DOCS=yes` - and if
+you don't want to download 120MB of docs from erlang.org, also set `KERL_BUILD_DOCS=yes`
 
 Note on .kerlrc
-===============
+---------------
 
-Since .kerlrc is a dot file for `/bin/sh`, running shell commands inside the .kerlrc will affect the shell and environment variables for the commands being executed later. For example, the shell `export` commands in .kerlrc will affect *your login shell environment* when activating `curl`.  Use with care.
+Since .kerlrc is a dot file for `/bin/sh`, running shell commands inside the
+.kerlrc will affect the shell and environment variables for the commands being
+executed later. For example, the shell `export` commands in .kerlrc will affect
+*your login shell environment* when activating `curl`.  Use with care.
 
 Glossary
-========
+--------
 
 Here are the abstractions kerl is handling:
 
@@ -181,10 +208,9 @@ Here are the abstractions kerl is handling:
 - **installations**: the result of deploying builds to filesystem locations (also referred to as "sandboxes")
 
 Commands reference
-==================
+------------------
 
-build
------
+### build
 
     kerl build <release_code> <build_name>
     kerl build git <git_url> <git_version> <build_name>
@@ -198,39 +224,60 @@ Creates a named build either from an official Erlang/OTP release or from a git r
 
 ##### Configure options
 
-You can specify the configure options to use when building Erlang/OTP with the `KERL_CONFIGURE_OPTIONS` variable, either in your $HOME/.kerlrc file or prepending it to the command line.
+You can specify the configure options to use when building Erlang/OTP with the
+`KERL_CONFIGURE_OPTIONS` variable, either in your $HOME/.kerlrc file or
+prepending it to the command line.
 
     $ KERL_CONFIGURE_OPTIONS=--enable-hipe kerl build R14B02 r14b02_hipe
 
 ##### Configure applications
 
-If non-empty, you can specify the subset of applications to use when building (and subsequent installing) Erlang/OTP with the `KERL_CONFIGURE_APPLICATIONS` variable, either in your $HOME/.kerlrc file or prepending it to the command line.
+If non-empty, you can specify the subset of applications to use when building
+(and subsequent installing) Erlang/OTP with the `KERL_CONFIGURE_APPLICATIONS`
+variable, either in your $HOME/.kerlrc file or prepending it to the command
+line.
 
     $ KERL_CONFIGURE_APPLICATIONS="kernel stdlib sasl" kerl build R15B01 r15b01_minimal
 
 ##### Configure disable applications
 
-If non-empty, you can specify the subset of applications to disable when building (and subsequent installing) Erlang/OTP with the `KERL_CONFIGURE_DISABLE_APPLICATIONS` variable, either in your $HOME/.kerlrc file or prepending it to the command line.
+If non-empty, you can specify the subset of applications to disable when
+building (and subsequent installing) Erlang/OTP with the
+`KERL_CONFIGURE_DISABLE_APPLICATIONS` variable, either in your $HOME/.kerlrc
+file or prepending it to the command line.
 
     $ KERL_CONFIGURE_DISABLE_APPLICATIONS="odbc" kerl build R16B02 r16b02_no_odbc
 
 ##### Enable autoconf
 
-You can enable the use of `autoconf` in the build process setting `KERL_USE_AUTOCONF=yes` in your $HOME/.kerlrc file
+You can enable the use of `autoconf` in the build process setting
+`KERL_USE_AUTOCONF=yes` in your $HOME/.kerlrc file
 
-*Note*: `autoconf` is always enabled for git builds
+**Note**: `autoconf` is always enabled for git builds
 
 ##### Using shell export command in .kerlrc
 
-Configure variables which includes spaces such as those in `CFLAGS` cannot be passed on with `KERL_CONFIGURE_OPTIONS`. In such a case you can use shell `export` command to define the environment variables for `./configure`. Note well: this method has a side effect to change your shell execution environment after activating a kerl installation of Erlang/OTP. Here is an example of .kerlrc for building Erlang/OTP for FreeBSD with clang compiler:
+Configure variables which includes spaces such as those in `CFLAGS` cannot be
+passed on with `KERL_CONFIGURE_OPTIONS`. In such a case you can use shell
+`export` command to define the environment variables for `./configure`. Note
+well: this method has a side effect to change your shell execution environment
+after activating a kerl installation of Erlang/OTP. Here is an example of
+.kerlrc for building Erlang/OTP for FreeBSD with clang compiler:
 
     # for clang
     export CC=clang CXX=clang CFLAGS="-g -O3 -fstack-protector" LDFLAGS="-fstack-protector"
     # compilation options
     KERL_CONFIGURE_OPTIONS="--disable-native-libs --enable-vm-probes --with-dynamic-trace=dtrace --with-ssl=/usr/local --with-javac --enable-hipe --enable-kernel-poll --with-wx-config=/usr/local/bin/wxgtk2u-2.8-config --without-odbc --enable-threads --enable-sctp --enable-smp-support"
 
-install
--------
+#### Building documentation
+
+Prior to kerl 1.0, kerl always downloaded prepared documentation from erlang.org. Now 
+if `KERL_BUILD_DOCS=yes` is set, kerl will build the man pages and HTML
+documentation from the source repository in which is working.
+
+**Note**: This variable takes precedent over the other documentation parameters. 
+
+### install
 
     kerl install <build_name> [path]
 
@@ -246,22 +293,35 @@ If path is omitted the current working directory will be used. However, if `KERL
 
 ##### SASL startup
 
-You can have SASL started automatically setting `KERL_SASL_STARTUP=yes` in your $HOME/.kerlrc file or prepending it to the command line.
+You can have SASL started automatically setting `KERL_SASL_STARTUP=yes` in your
+$HOME/.kerlrc file or prepending it to the command line.
 
 ##### Manpages installation
 
-You can have manpages installed automatically setting `KERL_INSTALL_MANPAGES=yes` in your $HOME/.kerlrc file or prepending it to the command line.
+You can have manpages installed automatically setting
+`KERL_INSTALL_MANPAGES=yes` in your $HOME/.kerlrc file or prepending it to the
+command line.
 
-*Note*: for git-based builds, kerl downloads and installs the newest official manpages which may or may not correspond to the contents of your local build.
+**Note**: for git-based builds, you want to set `KERL_BUILD_DOCS=yes`
 
 ##### HTML docs installation
 
-You can have HTML docs installed automatically setting `KERL_INSTALL_HTMLDOCS=yes` in your $HOME/.kerlrc file or prepending it to the command line.
+You can have HTML docs installed automatically setting
+`KERL_INSTALL_HTMLDOCS=yes` in your $HOME/.kerlrc file or prepending it to the
+command line.
 
-*Note*: for git-based builds, kerl downloads and installs the newest official HTML docs which may or may not correspond to the contents of your local build.
+*Note*: for git-based builds, you want to set `KERL_BUILD_DOCS=yes`
 
-deploy
-------
+#### Documentation installation
+
+Man pages will be installed to `[path]/man` and HTML docs will be installed in
+`[path]/html`.  The kerl `activate` script manipulates the MANPATH of the current
+shell such that `man 3 gen_server` or `erl -man gen_server` should work perfectly.
+
+(Do not fret - `kerl_deactivate` restores your shell's MANPATH to whatever its 
+original value was.)
+
+### deploy
 
     kerl deploy <[user@]host> [directory] [remote_directory]
 
@@ -279,28 +339,33 @@ If directory and remote_directory is omitted the current working directory will
 
 ##### Additional SSH options
 
-You can have additional options given to `ssh` by setting them in the `KERL_DEPLOY_SSH_OPTIONS` variable in your $HOME/.kerlrc file or on the command line, e.g. `KERL_DEPLOY_SSH_OPTIONS='-qx -o PasswordAuthentication=no'`.
+You can have additional options given to `ssh` by setting them in the
+`KERL_DEPLOY_SSH_OPTIONS` variable in your $HOME/.kerlrc file or on the command
+line, e.g. `KERL_DEPLOY_SSH_OPTIONS='-qx -o PasswordAuthentication=no'`.
 
 ##### Additional RSYNC options
 
-You can have additional options given to `rsync` by setting them in the `KERL_DEPLOY_RSYNC_OPTIONS` variable in your $HOME/.kerlrc file or on the command line, e.g. `KERL_DEPLOY_RSYNC_OPTIONS='--delete'`.
+You can have additional options given to `rsync` by setting them in the
+`KERL_DEPLOY_RSYNC_OPTIONS` variable in your $HOME/.kerlrc file or on the
+command line, e.g. `KERL_DEPLOY_RSYNC_OPTIONS='--delete'`.
 
-update
-------
+### update
 
     kerl update releases
 
-Fetches the up-to-date list of OTP releases from erlang.org.
+If `KERL_BUILD_BACKEND=tarball` this command fetches the up-to-date list of OTP
+releases from erlang.org.
+
+If it is set to `KERL_BUILD_BACKEND=git` this command fetches an up-to-date
+list of OTP tags from the official OTP github repository.
 
-list
-----
+### list
 
     kerl list <releases|builds|installations>
 
 Lists the releases, builds or installations available.
 
-delete
-------
+### delete
 
     kerl delete build <build_name>
     kerl delete installation <path>
@@ -317,8 +382,7 @@ $ kerl delete installation /srv/otp/r14b02
 The installation in /srv/otp/r14b02 has been deleted
 ```
 
-active
-------
+### active
 
     kerl active
 
@@ -328,8 +392,7 @@ Prints the path of the currently active installation, if any.
     The current active installation is:
     /srv/otp/r14b02
 
-status
-------
+### status
 
     kerl status
 
@@ -345,3 +408,10 @@ Prints the available builds and installations as well as the currently active in
     r14b02 /srv/otp/r14b02_dev
     ----------
     No Erlang/OTP kerl installation is currently active
+
+Changelog
+---------
+2 May 2016 - 1.0
+
+  - Support builds from git tags
+  - Support documentation builds/installs from source code
diff --git a/kerl b/kerl
index 4b9833a..1af46b4 100755
--- a/kerl
+++ b/kerl
@@ -1,5 +1,6 @@
 #! /bin/sh
 
+# Copyright (c) 2016 Mark Allen
 # Copyright (c) 2011, 2012 Spawngrid, Inc
 # Copyright (c) 2011 Evax Software <contact(at)evax(dot)org>
 #
@@ -24,7 +25,8 @@
 #Grep fix for mac pcre errors
 GREP_OPTIONS=''
 
-ERLANG_DOWNLOAD_URL=http://www.erlang.org/download
+ERLANG_DOWNLOAD_URL="http://www.erlang.org/download"
+OTP_GITHUB_URL="https://github.com/erlang/otp"
 
 # Default values
 : ${KERL_BASE_DIR:="$HOME"/.kerl}
@@ -57,6 +59,9 @@ fi
 if [ -n "$KERL_BUILD_PLT" ]; then
     _KBPLT="$KERL_BUILD_PLT"
 fi
+if [ -n "$KERL_BUILD_DOCS" ]; then
+    _KBD="$KERL_BUILD_DOCS"
+fi
 KERL_CONFIGURE_OPTIONS=
 KERL_CONFIGURE_APPLICATIONS=
 KERL_CONFIGURE_DISABLE_APPLICATIONS=
@@ -65,6 +70,7 @@ KERL_DEPLOY_SSH_OPTIONS=
 KERL_DEPLOY_RSYNC_OPTIONS=
 KERL_INSTALL_MANPAGES=
 KERL_BUILD_PLT=
+KERL_BUILD_DOCS=
 
 # ensure the base dir exsists
 mkdir -p "$KERL_BASE_DIR" || exit 1
@@ -96,6 +102,9 @@ fi
 if [ -n "$_KBPLT" ]; then
     KERL_BUILD_PLT="$_KBPLT"
 fi
+if [ -n "$_KBD" ]; then
+    KERL_BUILD_DOCS="$_KBD"
+fi
 
 if [ -z "$KERL_SASL_STARTUP" ]; then
     INSTALL_OPT=-minimal
@@ -103,20 +112,30 @@ else
     INSTALL_OPT=-sasl
 fi
 
+if [ -z "$KERL_BUILD_BACKEND" ]; then
+    KERL_BUILD_BACKEND="tarball"
+else
+    KERL_BUILD_BACKEND="git"
+    KERL_USE_AUTOCONF=1
+fi
+
 KERL_SYSTEM=$(uname -s)
 case "$KERL_SYSTEM" in
     Darwin|FreeBSD|OpenBSD)
         MD5SUM="openssl md5"
         MD5SUM_FIELD=2
         SED_OPT=-E
+        CP_OPT=-a
         ;;
     *)
         MD5SUM=md5sum
         MD5SUM_FIELD=1
         SED_OPT=-r
+        CP_OPT=-pr
         ;;
 esac
 
+
 usage()
 {
     echo "kerl: build and install Erlang/OTP"
@@ -126,7 +145,7 @@ usage()
     echo "  build    Build specified release or git repository"
     echo "  install  Install the specified release at the given location"
     echo "  deploy   Deploy the specified installation to the given host and location"
-    echo "  update   Update the list of available releases from erlang.org"
+    echo "  update   Update the list of available releases from your source provider"
     echo "  list     List releases, builds and installations"
     echo "  delete   Delete builds and installations"
     echo "  active   Print the path of the active installation"
@@ -141,6 +160,27 @@ if [ $# -eq 0 ]; then usage; fi
 
 get_releases()
 {
+    if [ "$KERL_BUILD_BACKEND" = "git" ]
+    then
+        echo "Getting the available releases from github.com..."
+        get_git_releases
+    else
+        echo "Getting the available releases from erlang.org..."
+        get_tarball_releases
+    fi
+}
+
+get_git_releases()
+{
+    git ls-remote --tags "$OTP_GITHUB_URL" \
+    | egrep -o 'OTP[_-][^^{}]+' \
+    | sed $SED_OPT 's/OTP[_-]//' \
+    | sort -n \
+    | uniq
+}
+
+get_tarball_releases()
+{
     curl -L -s $ERLANG_DOWNLOAD_URL/ | \
         sed $SED_OPT -e 's/^.*<[aA] [hH][rR][eE][fF]=\"\otp_src_([-0-9A-Za-z_.]+)\.tar\.gz\">.*$/\1/' \
                      -e '/^R1|^[0-9]/!d' | \
@@ -149,8 +189,13 @@ get_releases()
 
 update_checksum_file()
 {
-    echo "Getting the checksum file from erlang.org..."
-    curl -L $ERLANG_DOWNLOAD_URL/MD5 > "$KERL_DOWNLOAD_DIR"/MD5 || exit 1
+    if [ "$KERL_BUILD_BACKEND" = "git" ];
+    then
+        return 0
+    else
+        echo "Getting the checksum file from erlang.org..."
+        curl -L $ERLANG_DOWNLOAD_URL/MD5 > "$KERL_DOWNLOAD_DIR"/MD5 || exit 1
+    fi
 }
 
 ensure_checksum_file()
@@ -163,7 +208,6 @@ ensure_checksum_file()
 check_releases()
 {
     if [ ! -f "$KERL_BASE_DIR"/otp_releases ]; then
-        echo "Getting the available releases from erlang.org..."
         get_releases > "$KERL_BASE_DIR"/otp_releases
     fi
 }
@@ -305,42 +349,11 @@ do_git_build()
         rm -Rf "${KERL_BUILD_DIR:?}/$3"
         exit 1
     fi
-    LOGFILE="$KERL_BUILD_DIR/$3"/otp_build.log
     echo "Building Erlang/OTP $3 from git, please wait..."
-    ./otp_build autoconf $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1 && \
-        ./otp_build configure $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1
-    if [ $? -ne 0 ]; then
-        echo "Build error, see $LOGFILE"
-        exit 1
+    if [ -z "$KERL_BUILD_AUTOCONF" ]; then
+        KERL_USE_AUTOCONF=1
     fi
-    if [ -n "$KERL_CONFIGURE_APPLICATIONS" ]; then
-        find ./lib -maxdepth 1 -type d -exec touch -f {}/SKIP \;
-        for i in $KERL_CONFIGURE_APPLICATIONS; do
-            rm ./lib/"$i"/SKIP
-            if [ $? -ne 0 ]; then
-                echo "Couldn't prepare '$i' application for building"
-                exit 1
-            fi
-        done
-    fi
-    if [ -n "$KERL_CONFIGURE_DISABLE_APPLICATIONS" ]; then
-        for i in $KERL_CONFIGURE_DISABLE_APPLICATIONS; do
-            touch -f ./lib/"$i"/SKIP
-            if [ $? -ne 0 ]; then
-                echo "Couldn't disable '$i' application for building"
-                exit 1
-            fi
-        done
-    fi
-    ./otp_build boot -a $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1
-    if [ $? -ne 0 ]; then
-        echo "Build error, see $LOGFILE"
-        exit 1
-    fi
-    rm -f "$LOGFILE"
-    ./otp_build release -a "$KERL_BUILD_DIR/$3"/release_git > /dev/null 2>&1
-    cd "$KERL_BUILD_DIR/$3"/release_git || exit 1
-    ./Install $INSTALL_OPT "$KERL_BUILD_DIR/$3"/release_git > /dev/null 2>&1
+    _do_build "git" "$3"
     echo "Erlang/OTP $3 from git has been successfully built"
     list_add builds "git,$3"
 }
@@ -350,7 +363,40 @@ get_otp_version()
     echo $1 | sed $SED_OPT -e 's/R?([0-9]{1,2})[.AB]?[0-9]*/\1/'
 }
 
-do_build()
+show_logfile()
+{
+    echo "$1"
+    tail "$2"
+    echo
+    echo "Please see $2 for full details."
+}
+
+do_normal_build()
+{
+    assert_valid_release "$1"
+    assert_build_name_unused "$2"
+    FILENAME=""
+    download $1
+    mkdir -p "$KERL_BUILD_DIR/$2"
+    if [ ! -d "$KERL_BUILD_DIR/$2/$FILENAME" ]; then
+        echo "Extracting source code"
+        UNTARDIRNAME="$KERL_BUILD_DIR/$2/$FILENAME-kerluntar-$$"
+        rm -rf "$UNTARDIRNAME"
+        mkdir -p "$UNTARDIRNAME"
+        # github tarballs have a directory in the form of "otp-TAGNAME"
+        # Ericsson tarballs have the classic otp_src_RELEASE pattern
+        # Standardize on Ericsson format because that's what the rest of the script expects
+        (cd "$UNTARDIRNAME" && tar xfz "$KERL_DOWNLOAD_DIR/$FILENAME.tar.gz" && mv ./* "$KERL_BUILD_DIR/$2/otp_src_$1")
+        rm -rf "$UNTARDIRNAME"
+    fi
+
+    echo "Building Erlang/OTP $1 ($2), please wait..."
+    _do_build "$1" "$2"
+    echo "Erlang/OTP $1 ($2) has been successfully built"
+    list_add builds "$1,$2"
+}
+
+_do_build()
 {
     case "$KERL_SYSTEM" in
         Darwin)
@@ -395,39 +441,29 @@ do_build()
         ;;
     esac
 
-    assert_valid_release "$1"
-    assert_build_name_unused "$2"
-
-    FILENAME=otp_src_$1.tar.gz
-    download "$FILENAME"
-    mkdir -p "$KERL_BUILD_DIR/$2"
-    if [ ! -d "$KERL_BUILD_DIR/$2/otp_src_$1" ]; then
-        echo "Extracting source code"
-        UNTARDIRNAME="$KERL_BUILD_DIR/$2/otp_src_$1-kerluntar-$$"
-        rm -rf "$UNTARDIRNAME"
-        mkdir -p "$UNTARDIRNAME"
-        (cd "$UNTARDIRNAME" && tar xfz "$KERL_DOWNLOAD_DIR/$FILENAME" && mv ./* "$KERL_BUILD_DIR/$2/otp_src_$1")
-        rm -rf "$UNTARDIRNAME"
+    if [ -n "$KERL_BUILD_DOCS" ]; then
+        KERL_CONFIGURE_OPTIONS="$KERL_CONFIGURE_OPTIONS --prefix=$KERL_BUILD_DIR/$2/release_$1"
     fi
-    echo "Building Erlang/OTP $1 ($2), please wait..."
+
     ERL_TOP="$KERL_BUILD_DIR/$2/otp_src_$1"
     cd "$ERL_TOP" || exit 1
     LOGFILE="$KERL_BUILD_DIR/$2/otp_build_$1.log"
     if [ -n "$KERL_USE_AUTOCONF" ]; then
         ./otp_build autoconf $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1 && \
-            ./otp_build configure $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1
+            ./otp_build configure $KERL_CONFIGURE_OPTIONS >> "$LOGFILE" 2>&1
     else
         ./otp_build configure $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1
 
     fi
     if [ $? -ne 0 ]; then
-        echo "Build failed:"
-        tail "$LOGFILE"
-        echo
-        echo "Please see $LOGFILE for full details."
+        show_logfile "Configure failed." "$LOGFILE"
         list_remove builds "$1 $2"
         exit 1
     fi
+
+    # TODO: Check to see if we got any warnings from the configure
+    # step.
+
     if [ -n "$KERL_CONFIGURE_APPLICATIONS" ]; then
         find ./lib -maxdepth 1 -type d -exec touch -f {}/SKIP \;
         for i in $KERL_CONFIGURE_APPLICATIONS; do
@@ -450,16 +486,29 @@ do_build()
     fi
     ./otp_build boot -a $KERL_CONFIGURE_OPTIONS > "$LOGFILE" 2>&1
     if [ $? -ne 0 ]; then
-        echo "Build failed, see $LOGFILE"
+        show_logfile "Build failed." "$LOGFILE"
         list_remove builds "$1 $2"
         exit 1
     fi
+    if [ -n "$KERL_BUILD_DOCS" ]; then
+        echo "Building docs..."
+        make docs >> "$LOGFILE" 2>&1
+        if [ $? -ne 0 ]; then
+            show_logfile "Building docs failed." "$LOGFILE"
+            list_remove builds "$1 $2"
+            exit 1
+        fi
+        make install-docs >> "$LOGFILE" 2>&1
+        if [ $? -ne 0 ]; then
+            show_logfile "Installing docs failed." "$LOGFILE"
+            list_remove builds "$1 $2"
+            exit 1
+        fi
+    fi
     rm -f "$LOGFILE"
     ERL_TOP="$ERL_TOP" ./otp_build release -a "$KERL_BUILD_DIR/$2/release_$1" > /dev/null 2>&1
     cd "$KERL_BUILD_DIR/$2/release_$1" || exit 1
     ./Install $INSTALL_OPT "$KERL_BUILD_DIR/$2/release_$1" > /dev/null 2>&1
-    echo "Erlang/OTP $1 ($2) has been successfully built"
-    list_add builds "$1,$2"
 }
 
 do_install()
@@ -526,7 +575,7 @@ export _KERL_SAVED_REBAR_PLT_DIR
 _KERL_PATH_REMOVABLE="$absdir/bin"
 PATH="\${_KERL_PATH_REMOVABLE}:\$PATH"
 export PATH _KERL_PATH_REMOVABLE
-_KERL_MANPATH_REMOVABLE="$absdir/man"
+_KERL_MANPATH_REMOVABLE="$absdir/lib/erlang/man:$absdir/man"
 MANPATH="\${_KERL_MANPATH_REMOVABLE}:\$MANPATH"
 export MANPATH _KERL_MANPATH_REMOVABLE
 REBAR_PLT_DIR="$absdir"
@@ -544,34 +593,31 @@ if [ -n "\$BASH" -o -n "\$ZSH_VERSION" ]; then
     hash -r
 fi
 ACTIVATE
-    if [ "$rel" != "git" ]; then
-        if [ -n "$KERL_INSTALL_MANPAGES" ]; then
-            echo "Fetching and installing manpages..."
-            do_install_manpages "$rel"
-        fi
-
-        if [ -n "$KERL_INSTALL_HTMLDOCS" ]; then
-            echo "Fetching and installing HTML docs..."
-            do_install_htmldocs "$rel"
+    if [ -n "$KERL_BUILD_DOCS" ]; then
+        DOC_DIR="$KERL_BUILD_DIR/$1/release_$rel/lib/erlang"
+        if [ -d "$DOC_DIR" ]; then
+            echo "Installing docs..."
+            mkdir -p "$absdir/lib/erlang"
+            cp $CP_OPT "$DOC_DIR/" "$absdir/lib/erlang"
+            ln -s "$absdir/lib/erlang/man" "$absdir/man"
+            ln -s "$absdir/lib/erlang/doc" "$absdir/html"
         fi
     else
-        rel=$(get_newest_valid_release)
-        if [ $? -ne 0 ]; then
-            echo "No newest valid release"
-            exit 1
-        fi
-
-        if [ -n "$KERL_INSTALL_MANPAGES" ]; then
-            echo "CAUTION: Fetching and installing newest ($rel) manpages..."
-            do_install_manpages "$rel"
-        fi
+        if [ "$KERL_BUILD_BACKEND" = "tarball" ]; then
+            if [ "$rel" != "git" ]; then
+                if [ -n "$KERL_INSTALL_MANPAGES" ]; then
+                    echo "Fetching and installing manpages..."
+                    download_manpages "$rel"
+                fi
 
-        if [ -n "$KERL_INSTALL_HTMLDOCS" ]; then
-            echo "CAUTION: Fetching and installing newest ($rel) HTML docs..."
-            do_install_htmldocs "$rel"
+                if [ -n "$KERL_INSTALL_HTMLDOCS" ]; then
+                    echo "Fetching and installing HTML docs..."
+                    download_htmldocs "$rel"
+                fi
+            fi
         fi
     fi
-
+    
     if [ -n "$KERL_BUILD_PLT" ]; then
         echo "Building Dialyzer PLT..."
         build_plt "$absdir"
@@ -583,18 +629,18 @@ ACTIVATE
     echo "kerl_deactivate"
 }
 
-do_install_manpages()
+download_manpages()
 {
     FILENAME=otp_doc_man_$1.tar.gz
-    download "$FILENAME"
+    tarball_download "$FILENAME"
     echo "Extracting manpages"
     cd "$absdir" && tar xfz "$KERL_DOWNLOAD_DIR/$FILENAME"
 }
 
-do_install_htmldocs()
+download_htmldocs()
 {
     FILENAME="otp_doc_html_$1.tar.gz"
-    download "$FILENAME"
+    tarball_download "$FILENAME"
     echo "Extracting HTML docs"
     (cd "$absdir" && mkdir -p html && \
         tar -C "$absdir/html" -xzf "$KERL_DOWNLOAD_DIR/$FILENAME")
@@ -782,9 +828,27 @@ do_active()
 
 download()
 {
+    mkdir -p "$KERL_DOWNLOAD_DIR"
+    if [ "$KERL_BUILD_BACKEND" = "git" ]; then
+        FILENAME="OTP-$1"
+        github_download "$FILENAME.tar.gz"
+    else
+        FILENAME="otp_src_$1"
+        tarball_download "$FILENAME.tar.gz"
+    fi
+}
+
+github_download()
+{
     if [ ! -f "$KERL_DOWNLOAD_DIR/$1" ]; then
         echo "Downloading $1 to $KERL_DOWNLOAD_DIR"
-        mkdir -p "$KERL_DOWNLOAD_DIR"
+        curl -L "$OTP_GITHUB_URL/archive/$1" > "$KERL_DOWNLOAD_DIR/$1"
+    fi
+}
+
+tarball_download()
+{
+    if [ ! -f "$KERL_DOWNLOAD_DIR/$1" ]; then
         curl -L "$ERLANG_DOWNLOAD_URL/$1" > "$KERL_DOWNLOAD_DIR/$1"
         update_checksum_file
     fi
@@ -812,7 +876,7 @@ case "$1" in
                 echo "usage: $0 $1 <release> <build_name>"
                 exit 1
             fi
-            do_build "$2" "$3"
+            do_normal_build "$2" "$3"
         fi
         ;;
     install)