auto-patchelf: Move into pkgs/build-support

This is really not game-specific, so let's put it at the top-level and
also make sure we substitute all the commands we're using there, even
though a few of them are in PATH of stdenv so that it will always work
even when the programs available in stdenv should change someday.

Signed-off-by: aszlig <aszlig@nix.build>

2 files changed, 165 insertions, 0 deletions

diff --git a/pkgs/build-support/auto-patchelf/default.nix b/pkgs/build-support/auto-patchelf/default.nix
new file mode 100644
index 00000000..c7a055cb
--- /dev/null
+++ b/pkgs/build-support/auto-patchelf/default.nix
@@ -0,0 +1,16 @@
+{ stdenv, substituteAll, patchelf, binutils-unwrapped, findutils, file, glibc
+, gnugrep, gnused
+}:
+
+substituteAll {
+  src = ./setup-hook.sh;
+
+  inherit (stdenv) shell;
+  file = "${file}/bin/file";
+  find = "${findutils}/bin/find";
+  grep = "${gnugrep}/bin/grep";
+  ldd = "${glibc.bin}/bin/ldd";
+  objdump = "${binutils-unwrapped}/bin/objdump";
+  patchelf = "${patchelf}/bin/patchelf";
+  sed = "${gnused}/bin/sed";
+}
diff --git a/pkgs/build-support/auto-patchelf/setup-hook.sh b/pkgs/build-support/auto-patchelf/setup-hook.sh
new file mode 100644
index 00000000..6e34b4ef
--- /dev/null
+++ b/pkgs/build-support/auto-patchelf/setup-hook.sh
@@ -0,0 +1,149 @@
+declare -a autoPatchelfLibs
+
+gatherLibraries() {
+    autoPatchelfLibs+=("$1/lib")
+}
+
+addEnvHooks "$targetOffset" gatherLibraries
+
+isExecutable() {
+    [ "$(@file@ -b -N --mime-type "$1")" = application/x-executable ]
+}
+
+findElfs() {
+    @find@ "$1" -type f -exec @shell@ -c '
+        while [ -n "$1" ]; do
+            mimeType="$(@file@ -b -N --mime-type "$1")"
+            if [ "$mimeType" = application/x-executable \
+              -o "$mimeType" = application/x-sharedlib ]; then
+                echo "$1"
+            fi
+            shift
+        done
+    ' -- {} +
+}
+
+declare -a cachedDependencies
+
+addToDepCache() {
+    local existing
+    for existing in "${cachedDependencies[@]}"; do
+        if [ "$existing" = "$1" ]; then return; fi
+    done
+    cachedDependencies+=("$1")
+}
+
+declare -gi depCacheInitialised=0
+declare -gi doneRecursiveSearch=0
+declare -g foundDependency
+
+getDepsFromSo() {
+    @ldd@ "$1" 2> /dev/null | @sed@ -n -e 's/[^=]*=> *\(.\+\) \+([^)]*)$/\1/p'
+}
+
+checkElfDep() {
+    local errors ldout="$(@ldd@ "$1" 2> /dev/null)"
+    if errors="$(echo "$ldout" | @grep@ -F "not found")"; then
+        echo -e "Library dependencies missing for $1:\n$errors"
+    fi
+}
+
+populateCacheWithRecursiveDeps() {
+    local so found foundso
+    for so in "${cachedDependencies[@]}"; do
+        for found in $(getDepsFromSo "$so"); do
+            local libdir="${found%/*}"
+            local base="${found##*/}"
+            local soname="${base%.so*}"
+            for foundso in "${found%/*}/$soname".so*; do
+                addToDepCache "$foundso"
+            done
+        done
+    done
+}
+
+getSoArch() {
+    @objdump@ -f "$1" | @sed@ -ne 's/^architecture: *\([^,]\+\).*/\1/p'
+}
+
+findDependency() {
+    local filename="$1"
+    local arch="$2"
+    local lib dep
+
+    if [ $depCacheInitialised -eq 0 ]; then
+        for lib in "${autoPatchelfLibs[@]}"; do
+            for so in "$lib/"*.so*; do addToDepCache "$so"; done
+        done
+        depCacheInitialised=1
+    fi
+
+    for dep in "${cachedDependencies[@]}"; do
+        if [ "$filename" = "${dep##*/}" ]; then
+            if [ "$(getSoArch "$dep")" = "$arch" ]; then
+                foundDependency="$dep"
+                return 0
+            fi
+        fi
+    done
+
+    if [ $doneRecursiveSearch -eq 0 ]; then
+        populateCacheWithRecursiveDeps
+        doneRecursiveSearch=1
+        findDependency "$filename" "$arch" || return 1
+        return 0
+    fi
+    return 1
+}
+
+autoPatchelfFile() {
+    local dep rpath="" toPatch="$1"
+
+    local interpreter="$(< "$NIX_CC/nix-support/dynamic-linker")"
+    if isExecutable "$toPatch"; then
+        @patchelf@ --set-interpreter "$interpreter" "$toPatch"
+        if [ -n "$runtimeDependencies" ]; then
+            for dep in $runtimeDependencies; do
+                rpath="$rpath${rpath:+:}$dep/lib"
+            done
+        fi
+    fi
+
+    echo "searching for dependencies of $toPatch:" >&2
+
+    @patchelf@ --remove-rpath "$toPatch"
+
+    local missing="$(
+        @ldd@ "$toPatch" 2> /dev/null | \
+            @sed@ -n -e 's/^[\t ]*\([^ ]\+\) => not found.*/\1/p'
+    )"
+
+    for dep in $missing; do
+        echo -n "  $dep -> " >&2
+        if findDependency "$dep" "$(getSoArch "$toPatch")"; then
+            rpath="$rpath${rpath:+:}${foundDependency%/*}"
+            echo "found: $foundDependency" >&2
+        else
+            echo "not found!" >&2
+        fi
+    done
+
+    if [ -n "$rpath" ]; then
+        echo "setting RPATH to: $rpath" >&2
+        @patchelf@ --set-rpath "$rpath" "$toPatch"
+    fi
+}
+
+autoPatchelf() {
+    echo "automatically fixing dependencies for ELF files" >&2
+
+    cachedDependencies+=(
+        $(find "$out" \! -type d \( -name '*.so' -o -name '*.so.*' \))
+    )
+    local elffile
+    findElfs "$prefix" | while read -r elffile; do
+        autoPatchelfFile "$elffile"
+    done
+}
+
+postInstallHooks+=(autoPatchelf)